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BACKGROUND: At present, the biological functions and molecular changes of bone marrow mesenchymal stem cells in the tumor microenvironment of acute myeloid leukemia are still unclear. OBJECTIVE: To explore the changes in the biological function of bone marrow mesenchymal stem cells in acute myeloid leukemia and the role of acute myeloid leukemia conditioned medium by bioinformatics and experiment. METHODS: Differential genes were screened from GEO data sets, and enrichment analysis was performed. The protein-protein interaction network was constructed and the Hub gene was obtained. Bone marrow mesenchymal stem cells from patients with acute myeloid leukemia and healthy donors were cultured. Bone marrow mesenchymal stem cells from healthy donors were treated with acute myeloid leukemia conditioned culture solution. Each group was subjected to the adipogenic differentiation, osteogenic differentiation, staining of β-galactosidase, detection of the cell cycle, and validation of Hub genes. RESULTS AND CONCLUSION: (1) Gene expression data of bone marrow mesenchymal stem cells from acute myeloid leukemia patients and healthy donors were obtained from GSE84881, and 184 up-regulated genes and 140 down-regulated genes were screened. (2) The biological functions of enrichment mainly include cell cycle, adipocyte differentiation, cell metabolism, and MYC pathway. According to the Degree algorithm, 10 up-regulated Hub genes and 10 downregulated Hub genes were selected. (3) The cell in vitro experiment found that: compared with the control group, the surface antigen of acute myeloid leukemia mesenchymal stem cells did not change, but it showed enhanced lipid differentiation ability, weakened osteogenic differentiation ability, increased β-galactosidase positive cell number, altered cell morphology, arrested cell cycle, increased LGALS3 expression, and decreased MYC expression. Mesenchymal stem cells from healthy donors showed similar changes after being cultured in acute myeloid leukemia conditioned medium. (4) The results show that biological function of mesenchymal stem cells is altered in the acute myeloid leukemia microenvironment, which provides new insights into the interaction between mesenchymal stem cells and tumor cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: The occurrence and development of various ophthalmic diseases are closely related to excessive oxidative stress, and the inhibition of oxidative stress response may produce preventive and therapeutic effects. OBJECTIVE: To explore the role of Pax6 gene expression on hydrogen peroxide-induced aging of mouse bone marrow mesenchymal stem cells (BM-MSCs). METHODS: Resuscitated BM-MSCs, Pax6/BM-MSCs, and shPax6/BM-MSCs were treated with hydrogen peroxide for 24 hours, and then β-galactosidase staining was performed. The proliferation index Ki67 expression and apoptosis were detected by flow cytometry. The expression of senescence-associated molecules (Wnt7a, p21, and p53) was detected by RT-PCR. RESULTS AND CONCLUSION: (1) After hydrogen peroxide treatment, the cells of the three groups showed senescence phenotype and β-galactosidase staining was positive. Compared with BM -MSCs group, the expression of positive cells in Pax6/BM-MSCs group was less and that in the shPax6/BM-MSCs group was more, and the difference was statistically significant (P < 0.05). (2) The results of flow cytometry showed that compared with BM-MSCs group, the positive expression of Ki67 in the Pax6/BM-MSCs group increased and the level of apoptosis decreased, while the positive expression of Ki67 decreased and the level of apoptosis increased in the shPax6/BM-MSCs group; the difference was significantly different (P < 0.05). (3) RT-PCR showed that compared with the BM-MSCs group, the expression of Wnt7a, p53, and p21 decreased in the Pax6/BM-MSCs group, while the expression of Wnt7a, p53, and p21 increased in the shPax6/ BM-MSCs group; the difference was significantly different (P < 0.05). (4) These findings indicate that overexpression of Pax6 can antagonize the aging progression of BM-MSCs induced by hydrogen peroxide, which may be related to Wnt signaling pathway. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mesenchymal stem cells are susceptible to senescence during in vitro expansion, which greatly hinders their application in vivo and in vitro. How to improve the replicative senescence of mesenchymal stem cells is an urgent problem to be solved in tissue engineering. OBJECTIVE: To determine whether vascular endothelial growth factor combined with basic fibroblast growth factor can improve the aging of bone marrow mesenchymal stem cells caused by replicative passage. METHODS: Rat bone marrow mesenchymal stem cells were extracted by whole bone marrow adhesion method. Passage 2 cells were selected as normal control group. Passage 7 and later algebraic cells were selected as aging model group. Vascular endothelial growth factor (50 μg/L), basic fibroblast growth factor (10 μg/L), and their combination were administered. Cell proliferation was detected by CCK-8 assay. Cell senescence was observed by β-galactosidase activity staining. Cytoskeleton size and colony formation ability were observed by phalloidine staining and Giemsa staining, respectively, and the levels of senescence-related genes P16, P21, and P53 were detected by qRT-PCR. Gene expression levels of P16, P21, and P53 were tested by qRT-PCR. RESULTS AND CONCLUSION: (1) Vascular endothelial growth factor combined with basic fibroblast growth factor could promote the proliferation of aged bone marrow mesenchymal stem cells, which began to enter the plateau stage on day 9, and the absorbance value of the combined intervention group was significantly higher than that of the model group on day 9 (P < 0.05). (2) The phenotypic markers of the cells in the combined intervention group did not change, and the cell morphology changed from broad to slender. (3) Compared with the model group, the positive rate of β-galactosidase was significantly decreased (P < 0.01); the number of nuclei increased (P < 0.001); the total area of cytoskeleton increased (P < 0.01); colony formation ability was enhanced (P < 0.05); expression level of P16 was decreased (P < 0.01) in the combined intervention group. These results indicate that vascular endothelial growth factor combined with basic fibroblast growth factor can improve the senescence of bone marrow mesenchymal stem cells caused by replicative passage without changing the cell phenotype. [ABSTRACT FROM AUTHOR]

BACKGROUND: Quercetin plays an important role in the proliferation and differentiation of bone marrow mesenchymal stem cells, but less research has been done on its mechanism of promoting the migration of bone marrow mesenchymal stem cells. OBJECTIVE: To study the effect of quercetin on the migration of human bone marrow mesenchymal stem cells through in vitro experiments, and to explore the regulatory role of CCR1 and CXCR4. METHODS: Human bone marrow mesenchymal stem cells were selected as experimental subjects. CCK8 assay was used to detect the effect of quercetin on the proliferative activity of human bone marrow mesenchymal stem cells. Cell scratch assay and Transwell assay were used to detect the in vitro invasive and migratory abilities of human bone marrow mesenchymal stem cells after quercetin treatment, respectively. The role of quercetin in relation to CCR1 and CXCR4 was demonstrated with the help of molecular docking technology. Western blot assay and real-time fluorescence quantitative PCR were used to detect the migration-related chemokine expression after quercetin treatment. RESULTS AND CONCLUSION: (1) 5 and 10 μmol/L quercetin could significantly promote the proliferation of human bone marrow mesenchymal stem cells, and the drug concentration of 10 μmol/L resulted in the highest cell proliferation efficiency. (2) To better explore the dose-effect relationship of quercetin affecting the migration of human bone marrow mesenchymal stem cells, 5 and 10 μmol/L quercetin were selected for the subsequent experiments, and ligustrazine was used as the positive control drug, and the experiments were divided into blank control group, 5 μmol/L quercetin group, 10 μmol/L quercetin group, and 100 μmol/L ligustrazine group. (3) In vitro migration and invasion ability of human bone marrow mesenchymal stem cells were elevated in a concentration-dependent manner after quercetin treatment, and the migration effect of 10 μmol/L quercetin group was better than that of ligustrazine group. (4) The molecular docking results suggested that there was a strong interaction between quercetin and CCR1 and CXCR4. (5) Quercetin could up-regulate the expression of CCR1 and CXCR4 proteins and mRNA. (6) This study confirmed at the cellular level that quercetin could promote the migration of human bone marrow mesenchymal stem cells by targeting CCR1 and CXCR4. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is still controversy whether human bone marrow mesenchymal stem cells can maintain their biological characteristics, energy metabolism patterns, and multidirectional differentiation potential after long-term expression in vitro. Further comprehensive and systematic research is needed. OBJECTIVE: To evaluate the effects of long-term expansion in vitro on the biological characteristics of mesenchymal stem cells. METHODS: Human bone marrow mesenchymal stem cells cultured to passage 5, 10, and 15 in vitro. MTT assay was used to detect cell proliferation ability. Flow cytometry was used to detect cell cycle. The multi-differentiation potential of mesenchymal stem cells was detected by inducing to adipogenic, osteogenic and chondrogenic differentiation. Cell migration and invasion abilities were detected by scratch test and Transwell assay. The mitochondrial oxidative phosphorylation and glycolysis function were analyzed using energy metabolism analyzer. The cell senescence was detected by senescence-associated β-galactosidase staining. The expression levels of p21, p16, and p53 proteins were detected by western blot assay. RESULTS AND CONCLUSION: Bone marrow mesenchymal stem cells at passages 5, 10, and 15 grew adherently; the volume of passage 15 mesenchymal stem cells increased and its proliferation ability decreased; the percentage of S-phase cells decreased (P < 0.05). With the increase of culture passages, the migration and invasion abilities decreased gradually (P < 0.05). There was no significant difference in the differentiation potential, demonstrated by adipogenic, osteogenic and chondrogenesis induction. The ability of oxidative phosphorylation of mitochondria and glycolysis decreased gradually (P < 0.05). The number of senescence-associated β-galactosidase-positive cells increased with the increase of passages (P < 0.05), and the expression of senescence protein p21, p16, and p53 increased gradually (P < 0.05). The results indicated that the biological characterization of mesenchymal stem cells changed after long-term in vitro expansion. Mesenchymal stem cells cultured over 10 passages may have a reduced activity due to increasing senescence. Therefore, bone marrow mesenchymal stem cells cultured less than 10 passages are suitable for clinical research/therapy. [ABSTRACT FROM AUTHOR]

BACKGROUND: The pathogenesis of osteoporosis is complex, and its essence is the weakening of bone formation and the enhancement of bone absorption caused by various reasons, resulting in the imbalance of bone metabolism. In recent years, N6-methyladenosine has been found (N6-methyladenosine, m6A) methylation can prevent and treat osteoporosis by regulating bone metabolism. OBJECTIVE: Taking the regulation of bone metabolism by m6A methylation as an entry point, to systematically sort out and summarize the research progress of m6A methylation in osteoporosis, so as to provide certain theoretical reference bases for the search of new therapeutic targets for osteoporosis. METHODS: CNKI, WanFang, VIP, PubMed, MEDLINE, Nature, and Cochrane databases were retrieved for relevant literature published from database inception to 2023. The keywords were “osteoporosis, m6A methylation, bone metabolism, bone marrow mesenchymal stem cells, osteoblasts, osteoclasts” in Chinese and English. Duplicates and obsolete non-referenced documents were excluded, and a total of 73 standard papers were included for further review. RESULTS AND CONCLUSION: m6A methylation can affect the activity and differentiation of bone marrow mesenchymal stem cells, osteoblasts, and osteoclasts through various pathways to regulate bone metabolism and prevent osteoporosis. The regulatory process of m6A methylation is extremely complex, and its related proteins play different roles in different cells. Even in the same kind of cells, the same type of proteins may have radically different roles, regulating different physiological and pathological processes. [ABSTRACT FROM AUTHOR]

Treatment of articular cartilage remains a great challenge due to its limited self-repair capability. In tissue engineering, a scaffold with both mechanical strength and regenerative capacity has been highly desired. This study developed a double-network scaffold based on natural biomaterials of silk fibroin (SF) and methacrylated hyaluronic acid (MAHA) using three-dimensional (3D) printing technology. Structural and mechanical characteristics of the scaffold was first investigated. To enhance its ability of recruiting endogenous bone marrow mesenchymal stem cells (BMSCs), the scaffold was conjugated with a proven BMSC-specific-affinity peptide E7, and its biocompatibility and capacity of cell recruitment were assessed in vitro. Animal experiments were conducted to evaluate cartilage regeneration after transplantation of the described scaffolds. The SF/HA scaffolds exhibited a hierarchical macro-microporous structure with ideal mechanical properties, and offered a 3D spatial microenvironment for cell migration and proliferation. In vitro experiments demonstrated excellent biocompatibility of the scaffolds to support BMSCs proliferation, differentiation, and extracellular matrix production. In vivo, superior capacity of cartilage regeneration was displayed by the SF/MAHA + E7 scaffold as compared with microfracture and unconjugated SF/MAHA scaffold based on macroscopic, histologic and imaging evaluation. In conclusion, this structurally and functionally optimized SF/MAHA + E7 scaffold may provide a promising approach to repair articular cartilage lesions in situ. [ABSTRACT FROM AUTHOR]

BACKGROUND: Recent studies have shown that the occurrence and prevention of osteoporosis often focus on the cellular molecular level, and the mechanism of related signaling pathways is an important way to further understand osteoporosis. At present, traditional Chinese medicine has been proved to play a significant role in alleviating osteoporosis. Kaempferol as an emerging Chinese herbal extract has become the focus of clinical and basic research due to its antiosteoporosis effectiveness and mechanism of action. OBJECTIVE: To further understand the mechanism underlying the anti-osteoporosis effect of kaempferol active monomer through regulation of related signaling pathways by analyzing and collating domestic and foreign literature. METHODS: “Kaempferol, osteoporosis, osteoblasts, osteoclasts, bone marrow mesenchymal stem cells, signaling pathways” were used as Chinese and English search terms to search CNKI, WanFang, VIP, PubMed, Web of Science and Embase databases for relevant literature published from database inception to February 2023. RESULTS AND CONCLUSION: Kaempferol affects the occurrence and progression of osteoporosis to varying degrees by participating in the regulation of differentiation, proliferation and apoptosis of bone marrow mesenchymal stem cells, osteoblasts and osteoclasts. Kaempferol can prevent and treat osteoporosis by regulating various signaling pathways. Kaempferol can promote the proliferation and differentiation of osteoblasts and inhibit the formation of osteoclasts by interfering with the Wnt/β-catenin signaling pathway to regulate β-catenin protein counting and the formation of β-catenin-TCf/LEF complex. Kaempferol interferes with the RANK/RANKL pathway to maintain the dynamic balance of osteoclasts and bone homeostasis. Kaempferol can promote bone formation by intervening with the PI3K/Akt signaling pathway to upregulate the levels of related osteogenic factors Runx2 and Osterix and promote bone cell calcification. Kaempferol interferes with osteoclast differentiation and inhibits reactive oxygen species activity by regulating the ER/ERK pathway. Kaempferol inhibits the expression of ERK, JNK, p38/MAPK and decreases reactive oxygen species production by interfering with the MAPK pathway, thus protecting osteogenesis. Kaempferol enhances the expression of osteogenic factors, bone morphogenetic protein-2, p-Smad1/5/8, β-catenin and Runx2, inhibits the expression of Peroxisome proliferation-activated receptor, and promotes the differentiation and proliferation of osteoblasts through the BMP/Smad pathway. [ABSTRACT FROM AUTHOR]

BACKGROUND: Numerous basic and clinical trials have confirmed that the low survival rate after bone marrow mesenchymal stem cell transplantation is a serious constraint on its long-term therapeutic effect. Previous studies have shown that apoptosis-related factors play an important role in the apoptosis of bone marrow mesenchymal stem cells, of which apoptosis-inducing factor may be a key factor. OBJECTIVE: Bone marrow mesenchymal stem cells, of which apoptosis-inducing factor was knocked down, were transplanted into infarcted myocardium of mice, aiming to certify the importance of apoptosis-inducing factor in the survival of bone marrow mesenchymal stem cells to further recover cardiac function after infarction. METHODS: Firstly, bone marrow mesenchymal stem cells were infected with LV-AIF-shRNA lentivirus to down-regulate the expression of apoptosis-inducing factor protein. Flow cytometry, western blot assay, and RT-qPCR were used to detect the infection efficiency of lentivirus. CCK-8 assay was used to detect the cell viability of bone marrow mesenchymal stem cells with apoptosis-inducing factor knockdown under hypoxic and ischemic conditions. Then, with the mouse model of acute myocardial infarction constructed, the normal bone marrow mesenchymal stem cells and bone marrow mesenchymal stem cells with apoptosisinducing factor gene knockdown were transplanted into the model, respectively. The expression of apoptosis-inducing factor was examined by fluorescence immunoassay. Serum brain natriuretic peptide levels were detected by ELISA. Cardiac ultrasound was used to detect cardiac function. Myocardial fibrosis was observed by Masson staining. The expression of SRY gene was detected by RT-qPCR in apoptosis-inducing factor-knocked bone marrow mesenchymal stem cells after transplantation, reflecting cell survival. RESULTS AND CONCLUSION: (1) Bone marrow mesenchymal stem cells with apoptosis-inducing factor gene knockdown were successfully established by LVAIF-shRNA lentivirus infection, following 97.7% of infection efficiency, and notably decline of the expression of apoptosis-inducing factor (P < 0.001). (2) Under ischemia and hypoxia, the cell viability of apoptosis-inducing factor knockdown bone marrow mesenchymal stem cells was significantly increased compared with normal bone marrow mesenchymal stem cells. (3) Compared with normal bone marrow mesenchymal stem cells after transplantation, the survival number of bone marrow mesenchymal stem cells in the infarcted myocardium after apoptosis-inducing factor gene knockdown was significantly increased to 3.71 times (P < 0.001), and the apoptosis-inducing factor protein expression and myocardial fibrosis degree in the infarcted area were significantly reduced. (4) Compared with normal bone marrow mesenchymal stem cells, the serum brain natriuretic peptide level of bone marrow stem cells with apoptosis-inducing factor gene knockdown after transplantation was significantly decreased (P < 0.05), and left ventricular ejection fraction and left ventricular shortening fraction were significantly improved (P < 0.05). (5) These findings confirm that apoptosis-inducing factor gene knockdown can reduce myocardial fibrosis and improve cardiac function after acute myocardial infarction via enhancing the bone marrow mesenchymal stem cell viability and increasing the bone marrow mesenchymal stem cell survival after transplantation in the donor. [ABSTRACT FROM AUTHOR]

BACKGROUND: Stem cell therapy is an alternative treatment strategy for restoring damaged myocardial tissue after acute myocardial infarction. Exercise preconditioning can induce endogenous cardioprotective effects in the body. However, the efficacy and mechanism of the combined application are still unclear. OBJECTIVE: To explore the effect and possible mechanism of exercise preconditioning combined with bone marrow mesenchymal stem cells on the therapeutic effect in rats with acute myocardial infarction. METHODS: Seventy male SD rats were randomly divided into sham operation group, model group, stem cell therapy group, exercise preconditioning group, and combined intervention group. Rats in the exercise preconditioning group and combined intervention group underwent 8-week aerobic exercise on the treadmill before modeling. The animal model of acute myocardial infarction was made by ligating the anterior descending coronary artery. The stem cell therapy group and the combined intervention group were injected with bone marrow mesenchymal stem cells (1×109 L-1, 1 mL) through the tail vein the next day after modeling. After 4 weeks of treatment, the exercise performance was evaluated by a graded treadmill exercise test. The cardiac structure and function were detected by echocardiography. The left ventricle was isolated. 2,3,5-Triphenyltetrazolium chloride staining was used to evaluate myocardial infarct size. Masson staining was used to obtain collagen volume fraction. CD31 immunohistochemical staining was used to detect myocardial capillary density. TUNEL staining was used to detect myocardial cell apoptosis. Immunoblotting was used to detect protein expression levels of stromal cell-derived factor 1, CXC chemokine receptor protein 4, tumor necrosis factor-α, interleukin-10, and vascular endothelial growth factor. RESULTS AND CONCLUSION: (1) Intervention efficacy: Compared with the sham operation group, exercise performance, left ventricular ejection fraction, left ventricular fractional shortening, and CD31 positive cell rate decreased (P < 0.05); myocardial infarct size, collagen volume fraction, and myocardial apoptotic rate increased (P < 0.05) in the model group. Compared with the model group, exercise performance was not statistically significant (P > 0.05) in the stem cell therapy group, and the exercise performance improved (P < 0.05) in the exercise preconditioning and combined intervention groups; left ventricular ejection fraction, left ventricular fractional shortening, and CD31 positive cell rate increased (P < 0.05), and the myocardial infarct size, collagen volume fraction, and cardiomyocyte apoptosis rate decreased (P < 0.05) in the stem cell therapy, exercise preconditioning, and combined intervention groups. Compared with the stem cell therapy group, exercise performance, left ventricular ejection fraction, left ventricular shortening fraction, and CD31 positive cell rate increased (P < 0.05), myocardial infarct size, collagen volume fraction, and myocardial cell apoptosis rate decreased (P < 0.05) in the combined intervention group. (2) Protein expression: Compared with the sham operation group, the expression of tumor necrosis factor-α increased (P < 0.05), while interleukin-10 and vascular endothelial growth factor expression decreased (P < 0.05) in the model group. Compared with the model group, the expression of CXC chemokine receptor protein 4 increased (P < 0.05) in the stem cell therapy group and combined intervention group, and the expression of tumor necrosis factor-α decreased (P < 0.05) while interleukin-10 and vascular endothelial growth factor increased (P < 0.05) in the stem cell therapy group, exercise preconditioning group, and combined intervention group. Compared with the stem cell therapy group, the expression of tumor necrosis factor-α decreased (P < 0.05), while CXC chemokine receptor protein 4, interleukin-10, and vascular endothelial growth factor increased (P < 0.05) in the combined intervention group. To conclude, exercise preconditioning can enhance the therapeutic effect of bone marrow mesenchymal stem cells in rats with acute myocardial infarction, which can inhibit cardiac remodeling, improve cardiac function, and delay the progress of heart failure. Its mechanism is related to the promotion of stem cell homing, inhibition of inflammatory response, and promotion of angiogenesis. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, research on the interaction mechanism between the immune system and the skeleton in postmenopausal osteoporosis has become a hot topic. However, the impact of changes in key immune-related cytokine expression on postmenopausal osteoporosis remains unclear and requires further exploration. OBJECTIVE: To investigate the differential expression of immune-related cytokines in bone marrow mesenchymal stem cells of mice with postmenopausal osteoporosis by bioinformatics methods. METHODS: Postmenopausal osteoporosis mouse model was established through ovariectomy. Bone marrow mesenchymal stem cells were obtained by the whole bone marrow adherence method and passaged to passage 2. RayBio L-Series Mouse Antibody Array 308 Glass Slide Kit immune-related factor antibody chip was used to detect the differentially expressed proteins in bone marrow mesenchymal stem cells from ovariectomy and sham-operation mice. Gene ontology, Kyoto Encyclopedia of Genes and Genomes enrichment analysis, and protein-protein interaction network analysis were performed to screen common Hub genes by MCC, EPC, and MNC algorithms. RESULTS AND CONCLUSION: This study identified a total of 68 differentially expressed genes. Gene ontology analysis revealed that the differentially expressed genes were enriched in terms including “immune system processes”, “extracellular regions”, and “signal receptor binding”. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the differentially expressed genes were mainly enriched in “cytokine-cytokine receptor interactions”, “tumor necrosis factor signaling pathways”, and “chemokine signaling pathways”. Further screening was performed by constructing a protein-protein interaction network analysis of these 68 differentially expressed genes to identify 8 Hub genes. The violin plot and correlation matrix showed that the expression levels of these 8 Hub genes were significantly down-regulated in the ovariectomy group compared to the sham-operation group. These results demonstrated that there was differential expression of immune-related factors in bone marrow mesenchymal stem cells of postmenopausal osteoporosis mice, and key genes involved in cytokine-cytokine receptor interactions, immune system-related processes, and potential targeted signaling pathways and cellular biological processes were identified, providing new promising targets for the diagnosis, treatment, and prevention of postmenopausal osteoporosis. [ABSTRACT FROM AUTHOR]

Objective: To discuss the effect of bone marrow mesenchymal stem cells (BMSCs) -derived exosomes (Exo) on isoproterenol (ISO) -induced myocardial fibrosis in the rats, and to clarify its mechanism. Methods: The Exo was isolated from the BMSCs and characterized by transmission electron microscope, nanoparticle tracking analysis, and Western blotting methods. Forty SD rats were divided into control group, model group, BMSCs-Exo group, and BMSCs-Exo+ferroptosis activator (Erastin) group, and there were 10 rats in each group. The myocardial fibrosis models were established by subcutaneous injection of ISO in all the rats except control group. The rats in BMSCs-Exo and BMSCs-Exo+Erastin groups were given BMSCs-Exo, and the rats in BMSCs-Exo+Erastin group were additionally injected with Erastin intraperitoneally. After 4 weeks, echocardiography was used to detect the left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), left ventricular end diastolic diameter (LVEDD), and left ventricular end systolic diameter (LVESD) of the rats in various groups; HE staining was used to observe the pathomorphology of myocardium tissue of the rats in various groups; Masson staining was used to observe the fibrosis degrees of myocardium tissue of the rats in various groups; immunohistochemistry was used to detect the positive expression rates of α-smooth muscle actin (α-SMA), type Ⅰ collagen (COL-Ⅰ), and type Ⅲ collagen (COL-Ⅲ) in myocardium tissue of the rats in various groups; colorimetry was used to detect the Fe2+ level in myocardium tissue of the rats in various groups; Western blotting method was used to detect the expression levels of acyl-CoA synthetase long chain family member 4 (ACSL4), ferritin heavy chain 1 (FTH1), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11) proteins in myocardium tissue of the rats in various groups. Results: The particles isolated from BMSCs had a typical lipid bilayer structure, and most particle sizes distributed around 100 nm. High expression levels of CD63, CD9, tumor susceptibility gene 101 (TSG101), and heat shock protein 70 (HSP70) proteins confirmed the particles as Exo. Compared with control group, the LVEF and LVFS of the rats in model group were significantly decreased (P<0. 05), LVEDD and LVESD were increased (P<0. 05), the myocardial cell arrangement was disordered, some nuclear shrinkage and necrosis were seen, the collagen volume fraction (CVF) was significantly increased (P< 0. 05), the positive expression rates of α -SMA, COL-Ⅰ, and COL-Ⅲ were significantly increased (P< 0. 05), the Fe2+ level in myocardium tissue was significantly increased (P<0. 05), the expression level of ACSL4 protein was significantly increased (P<0. 05), and the expression levels of FTH1, GPX4, and SLC7A11 proteins were significantly decreased (P<0. 05). Compared with model group, the LVEF and LVFS of the rats in BMSCs-Exo group were significantly increased (P<0. 05), the LVEDD and LVESD were significantly decreased (P<0. 05), the myocardial tissue damage was significantly alleviated, the CVF was significantly decreased (P<0. 05), the positive expression rates of α -SMA, COL- Ⅰ, and COL- Ⅲ were significantly decreased (P<0. 05), the Fe2+ level in myocardium tissue was significantly decreased (P<0. 05), the expression level of ACSL4 protein was significantly decreased (P<0. 05), and the expression levels of FTH1, GPX4, and SLC7A11 proteins were significantly increased (P<0. 05). Compared with BMSCs-Exo group, the LVEF and LVFS of the rats in BMSCs-Exo+Erastin group were significantly decreased (P<0. 05), the LVEDD and LVESD were significantly increased (P<0. 05), the myocardial cell edema and necrosis were seen, the CVF was significantly increased (P<0. 05), the positive expression rates of α -SMA, COL-Ⅰ, and COL-Ⅲ were significantly increased (P<0. 05), the Fe2+ level in myocardium tissue was significantly increased (P<0. 05), the expression level of ACSL4 protein was significantly increased (P<0. 05), and the expression levels of FTH1, GPX4, and SLC7A11 proteins were significantly decreased (P<0. 05). Conclusion: BMSC-derived Exo can improve the myocardial fibrosis in the rats induced by ISO, and its mechanism may be related to the inhibition of ferroptosis. [ABSTRACT FROM AUTHOR]

Objective·To explore the effect of all-trans retinoic acid (ATRA) of different concentrations on osteogenic differentiation of jaw bone mesenchymal stem cells (jBMSCs) in rats. Methods·jBMSCs from 4-week-old Sprague-Dawley (SD) rats were isolated and cultured with whole bone marrow adherence method. The surface antigens were identified by using flow cytometry. Alkaline phosphatase (ALP) staining/alizarin red staining, oil red O staining and alcian blue staining were used to prove the multilineage differentiation potential of jBMSCs after osteogenic, adipogenic and chondrogenic induction respectively. jBMSCs were induced in osteogenic medium with ATRA of concentration of 0.01, 0.1, 1, 5, 10, 20 μmol/L in vitro, and dimethyl sulfoxide (DMSO) was used as control group. Cell viability of jBMSCs in different groups were determined by CCK8. ALP staining and alizarin red staining were used to investigate the osteogenic ability of jBMSCs in each group and screened the concentrations for subsequent experiments. Quantitative real-time polymerase chain reaction (qPCR) and immunofluorescence staining were used to analyze the expressions of osteogenesis-related genes and proteins in jBMSCs of different concentrations. Results·The flow cytometry analysis showed that more than 98% of P1 jBMSCs were positive for CD29+CD90+CD31-CD45-, which was congruent with the characteristics of bone mesenchymal stem cells. The results of ALP staining/alizarin red staining, oil red O staining and alcian blue staining indicated that the P1 jBMSCs had the multilineage differentiation potential of osteogenesis, adipogenesis and chondrogenesis. The results of ALP staining/alizarin red staining showed that the osteogenic activity and mineralization ability of jBMSCs in 0.01, 0.1 and 1 μmol/L ATRA groups were increased compared with those in the control group, while the osteogenic activity and mineralization ability were decreased when the concentration of ATRA increased, especially higher than 5 μmol/L (all P <0.05). qPCR analysis showed that the mRNA expression levels of osteogenesis-related genes such as Alp, bone sialoprotein (Bsp), collagen type Ⅰ α1 (Col1a1) and osteocalcin (Ocn) were higher in the 0.1 and 1 μmol/L ATRA groups compared to the control group. However, further increasing the concentration of ATRA led to a decrease in gene expression levels, and when the concentration exceeded 5 μmol/L, it began to be lower than the control group level (all P<0.05). The immunofluorescence staining showed that the expression of osteogenic related proteins SP7, ALP and OCN in the 0.1 and 1 μmol/L ATRA groups were increased compared to the control group, while further increasing the concentration of ATRA led to a decrease in protein expression. When the concentration was higher than 5 μmol/L, it began to be lower than the control group level (all P<0.05). Conclusion·Lower concentrations (0.1, 1 μmol/L) of ATRA can promote the osteogenic differentiation of rat jBMSCs, and the promoting effect reaches its peak at 0.1 μmol/L, while the effect can be weakened by further increasing the concentration. Higher concentrations (5, 10, 20 μmol/L) of ATRA could inhibit the osteogenic differentiation of rat jBMSCs, showing an inhibitory effect. In this study, the dualdirectional effect of retinoic acid on osteogenic differentiation of jBMSCs was demonstrated in vitro, and 0.1 μmol/L ATRA was identified as the optimal concentration for osteogenic differentiation of jBMSCs in rats, which provided a reference basis for the development of in vivo studies and clinical application of ATRA. [ABSTRACT FROM AUTHOR]

Objective·To explore the effect of all-trans retinoic acid (ATRA) of different concentrations on osteogenic differentiation of jaw bone mesenchymal stem cells (jBMSCs) in rats.Methods·jBMSCs from 4-week-old Sprague-Dawley (SD) rats were isolated and cultured with whole bone marrow adherence method. The surface antigens were identified by using flow cytometry. Alkaline phosphatase (ALP) staining/alizarin red staining, oil red O staining and alcian blue staining were used to prove the multilineage differentiation potential of jBMSCs after osteogenic, adipogenic and chondrogenic induction respectively. jBMSCs were induced in osteogenic medium with ATRA of concentration of 0.01, 0.1, 1, 5, 10, 20 μmol/L in vitro, and dimethyl sulfoxide (DMSO) was used as control group. Cell viability of jBMSCs in different groups were determined by CCK8. ALP staining and alizarin red staining were used to investigate the osteogenic ability of jBMSCs in each group and screened the concentrations for subsequent experiments. Quantitative real-time polymerase chain reaction (qPCR) and immunofluorescence staining were used to analyze the expressions of osteogenesis-related genes and proteins in jBMSCs of different concentrations.Results·The flow cytometry analysis showed that more than 98% of P1 jBMSCs were positive for CD29+CD90+CD31-CD45-, which was congruent with the characteristics of bone mesenchymal stem cells. The results of ALP staining/alizarin red staining, oil red O staining and alcian blue staining indicated that the P1 jBMSCs had the multilineage differentiation potential of osteogenesis, adipogenesis and chondrogenesis. The results of ALP staining/alizarin red staining showed that the osteogenic activity and mineralization ability of jBMSCs in 0.01, 0.1 and 1 μmol/L ATRA groups were increased compared with those in the control group, while the osteogenic activity and mineralization ability were decreased when the concentration of ATRA increased, especially higher than 5 μmol/L (all P

BACKGROUND: Small diameter artificial vessels are urgently needed to treat coronary artery and peripheral artery diseases in clinical practice. At present, vascular tissue engineering has become the main method for preparing small diameter artificial vessels. Selecting suitable biomaterials and cell sources is the key factor for successful construction of small diameter tissue engineered vessels. OBJECTIVE: To observe the effect of four kinds of electrospinning membrane materials on proliferation, adhesion and differentiation of bone marrow mesenchymal stem cells into vascular smooth muscle cells. METHODS: Bone marrow mesenchymal stem cells were isolated and extracted from SD rats. The bone marrow mesenchymal stem cells were inoculated separately on polycaprolactone (PCL), polycaprolactone-hyaluronic acid (PCL-HA), polycaprolactone-silk-filament proteins (PCL-SF), and polycaprolactone- gelatin (PCL-GEL) electrospinning membrane materials. After 1, 3, and 7 days of culture, the cell arrangement on the material was observed under scanning electron microscope. The proliferation and adhesion of the material were observed by phalloidin staining. The mRNA expressions of CD90, Meflin, and transforming growth factor β were detected by qRT-PCR. After 7 days of induced differentiation into vascular smooth muscle cells, the mRNA expression of ɑ-smooth muscle actin on the material was detected by qRT-PCR. RESULTS AND CONCLUSION: (1) Bone marrow mesenchymal stem cells were arranged along the fibers of the four kinds of electrospinning membranes under scanning electron microscopy. (2) Phalloidin staining showed the regular distribution of bone marrow mesenchymal stem cells on the four kinds of electrospinning membranes and parallel distribution along the fiber direction. Moreover, PCL-HA, PCL-SF, and PCL-GEL electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells than PCL electrospinning membranes. Compared with PCL-HA and PCL-GEL electrospinning membranes, PCL-SF electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells. (3) qRT-PCR showed that the four kinds of electrospun membrane materials could maintain the mRNA expression of CD90 and Meflin in bone marrow mesenchymal stem cells, but there was no significant difference between groups (P > 0.05). The mRNA expression of transforming growth factor β in PCL-HA, PCL-SF, and PCL-GEL groups was higher than that in PCL group on days 1 and 7 (P < 0.05), and the mRNA expression of transforming growth factor β in PCL-SF group was higher than that in the other three groups on days 3 and 7 (P < 0.05). The mRNA expression of transforming growth factor β in PCL-HA group was higher than that in PCL-GEL group on day 7 (P < 0.05). (4) qRT-PCR showed that the mRNA expression of ɑ-smooth muscle actin in PCL-SF group was higher than that in the other three groups (P < 0.05), and that in PCL-HA group was higher than that in PCL group (P < 0.05). (5) The results indicate that compared with PCL, PCL-HA and PCL-GEL electrospinning membranes, PCL-SF electrospinning membranes combined with bone marrow mesenchymal stem cells are more suitable for the preparation of small diameter tissue engineered vessels. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bone relies on the close connection between blood vessels and bone cells to maintain its integrity. Bones are in a physiologically hypoxic environment. Therefore, the study of angiogenesis and osteogenesis in hypoxic environment is closer to the microenvironment in vivo. OBJECTIVE: To explore the influence of Wenshen Tongluo Zhitong (WSTLZT) formula on H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell co-culture system in hypoxia environment and its related mechanism. METHODS: Enzyme digestion method and flow sorting technique were used to isolate and identify H-type bone microvascular endothelial cells. Mouse bone marrow mesenchymal stem cells were isolated and obtained by bone marrow adhesion method. H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell hypoxic co-culture system was established using Transwell chamber and anoxic culture workstation. WSTLZT formula powder was used to intervene in each group at a mass concentration of 50 and 100 μg/mL. The angiogenic function of H-type bone microvascular endothelial cells in the co-culture system was evaluated by scratch migration test and tube formation test. The osteogenic differentiation ability of bone marrow mesenchymal stem cells in the cocultured system was evaluated by alkaline phosphatase staining and alizarin red staining. The protein and mRNA expression changes of PDGF/PI3K/AKT signal axis related molecules in H-type bone microvascular endothelial cells in the co-cultured system were detected by Western Blotting and q-PCR, respectively. RESULTS AND CONCLUSION: (1) Compared with the normal oxygen group, the scratch mobility and new blood vessel length of H-type bone microvascular endothelial cells were significantly higher (P < 0.05); the osteogenic differentiation capacity of bone marrow mesenchymal stem cells was higher (P < 0.05); the expression of PDGF/PI3K/AKT axis-related molecular protein and mRNA increased (P < 0.05) in the hypoxia group. (2) Compared with the hypoxia group, scratch mobility and new blood vessel length were significantly increased in the H-type bone microvascular endothelial cells (P < 0.05); bone marrow mesenchymal stem cells had stronger osteogenic function (P < 0.05); the expression of PDGF/PI3K/AKT axis-related molecular proteins and mRNA further increased (P < 0.05) after treatment with different dose concentrations of WSTLZT formula. These findings conclude that H-type angiogenesis and osteogenesis under hypoxia may be related to the PDGF/PI3K/AKT signaling axis, and WSTLZT formula may promote H-type vasculo-dependent bone formation by activating the PDGF/PI3K/AKT signaling axis, thereby preventing and treating osteoporosis [ABSTRACT FROM AUTHOR]

BACKGROUND: Stem cell therapy has broad prospects in improving cardiac remodeling after myocardial infarction; however, alteration in the myocardial microenvironment affects the therapeutic efficacy of stem cells. Exercise preconditioning is similar to ischemic preconditioning and can have a protective effect on the myocardium. However, little attention has been paid to the effects and mechanisms of the combined effects of exercise preconditioning and stem cell transplantation. OBJECTIVE: To observe the effect of exercise preconditioning on bone marrow mesenchymal stem cell transplantation in rats with myocardial infarction and to explore the mechanism of local inflammatory microenvironment. METHODS: Eighty female SD rats were randomly divided into sham operation group, model group, transplantation group, and combination group, with 20 rats in each group. The rat model of myocardial infarction was made by ligating the left anterior descending branch of coronary artery. The sham operation group was only threaded without ligature. The transplantation and combination groups were injected with bone marrow mesenchymal stem cells of male rats into the myocardium after modeling. In addition, the combination group also required 8 weeks of treadmill exercise (i.e., exercise preconditioning) before modeling. Four weeks after stem cell transplantation, exercise performance was measured by incremental exercise exhaustion test; cardiac structure and function were measured by echocardiography; left ventricular hemodynamics was measured by pressure-volume catheterization, and myocardial histopathology was observed by in situ staining and myocardial collagen volume fraction was obtained. Quantitative reverse transcription polymerase chain reaction was used to detect left ventricular pro-inflammatory factor (interleukin-1β, interleukin-6, tumor necrosis factor-α), anti-inflammatory factor (interleukin-10), sexdetermining region of Y chromosome, and fetal genes (atrial natriuretic peptide, brain natriuretic peptide, β-myosin heavy chain) mRNA expression level at 1, 7 days and 4 weeks after stem cell transplantation. RESULTS AND CONCLUSION: (1) Four weeks after stem cell transplantation: compared with sham operation group, exercise performance, and left ventricular ejection fraction were reduced (P < 0.05); myocardial infarction area, cardiomyocyte cross-sectional area, and collagen volume fraction were increased (P < 0.05); the mRNA expression of fetal genes and pro-inflammatory factors were up-regulated (P < 0.05), and the mRNA expression of interleukin-10 was downregulated (P < 0.05) in the model group. Compared with the model group, exercise performance and left ventricular ejection fraction were increased (P < 0.05); myocardial infarction area, cardiomyocyte cross-sectional area, and collagen volume fraction were decreased (P < 0.05); mRNA expression of fetal genes and pro-inflammatory factors was down-regulated (P < 0.05), and that of interleukin-10 had no significant change (P > 0.05) in the transplantation group. Compared with the transplantation group, all the above indicators in the combination group were further improved (P < 0.05). (2) One day and 7 days after stem cell transplantation, compared with the transplantation group, the mRNA expression of sex-determining region of Y chromosome in the combination group increased (P < 0.05). (3) Correlation analysis showed that interleukin-1β, interleukin-6 (except on the 1st day after transplantation), and tumor necrosis factor-α were negatively correlated with the mRNA expression of sex-determining region of Y chromosome (P < 0.05), while interleukin-10 was positively correlated with that of sex-determining region of Y chromosome (P < 0.05). These findings suggest that exercise preconditioning can enhance the effect of bone marrow mesenchymal stem cell transplantation in rats with myocardial infarction, which is characterized by suppression of cardiac remodeling and further amelioration of cardiac function. The mechanism is related to the improvement of the myocardial inflammatory microenvironment to promote bone marrow mesenchymal stem cell retention and survival. [ABSTRACT FROM AUTHOR]

BACKGROUND: Psoralen has a strong anti-osteoporotic activity and may have a restorative effect on chemotherapy-induced osteoporosis. OBJECTIVE: To explore the restorative effect of psoralen on the osteogenic differentiation of bone marrow mesenchymal stem cells in mice inhibited by cyclophosphamide and its mechanism. METHODS: C57BL/6 mouse bone marrow mesenchymal stem cells were isolated and cultured. Effect of psoralen on viability of bone marrow mesenchymal stem cells was detected by MTT assay. Osteogenic induction combined with alkaline phosphatase staining was used to determine the optimal dose of psoralen to restore the osteogenic differentiation of bone marrow mesenchymal stem cells inhibited by cyclophosphamide. The mRNA expression levels of Runx2, alkaline phosphatase, Osteocalcin, osteoprotegerin, and Wnt/β-catenin signaling pathway-related genes Wnt1, Wnt4, Wnt10b, β-catenin, and c-MYC were measured by RT-qPCR at different time points under the intervention with psoralen. The protein expression of osteogenic specific transcription factor Runx2 and Wnt/β-catenin signaling pathway related genes Active β-catenin, DKK1, c-MYC, and Cyclin D1 was determined by western blot assay at different time points under the intervention with psoralen. RESULTS AND CONCLUSION: (1) There was no significant effect of different concentrations of psoralen on the viability of bone marrow mesenchymal stem cells. The best recovery of the inhibition of osteogenic differentiation of bone marrow mesenchymal stem cells caused by cyclophosphamide was under the intervention of psoralen at a concentration of 200 μmol/L. (2) Psoralen reversed the reduction in osteogenic differentiation marker genes Runx2, alkaline phosphatase, Osteocalcin and osteoprotegerin mRNA expression and Runx2 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium. (3) Psoralen reversed the decrease in Wnt/β-catenin pathway-related genes Wnt4, β-catenin, c-MYC mRNA and Active β-catenin, c-MYC, and Cyclin D1 protein expression and the increase in DKK1 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium. (4) The results showed that cyclophosphamide inhibited osteogenic differentiation of bone marrow mesenchymal stem cells in mice, and psoralen had a restorative effect on it. The best intervention effect was achieved at a concentration of 200 μmol/L psoralen, and this protective effect might be related to the activation of Wnt4/β-catenin signaling pathway by psoralen. [ABSTRACT FROM AUTHOR]

BACKGROUND: Osteoarthritis is one of the most common senile chronic degenerative diseases in China. Due to its complex pathogenesis and cellular molecular communication pathways, there is currently no effective method to slow down the progression of osteoarthritis. Studies have found that transforming growth factor-β is one of the key factors in the maintenance and regulation of joint stability and plays a significant role in the formation of early joints, as well as the development of bone and cartilage, and the remodeling of joints at various stages. OBJECTIVE: To review the regulatory role of the transforming growth factor-β subfamily in the occurrence and development of osteoarthritis, both domestically and internationally in recent years, to analyze the impacts it has at different stages of osteoarthritis, and to explore the potential application prospects of transforming growth factor-β in the clinical treatment of osteoarthritis, with a view to informing clinical treatment protocols.. METHODS: The relevant articles were searched by computer from CNKI Database and PubMed Database. The search terms were “osteoarthritis, transforming growth factor, signaling pathway, bone remodeling, cartilage degeneration, angiogenesis, treatment” in Chinese and English, respectively. Finally, 57 articles were included for review. RESULTS AND CONCLUSION: The pathogenesis of osteoarthritis remains a subject of ongoing exploration with no unified consensus. Numerous studies highlight the close correlation between osteoarthritis and cytokines, focusing on the transforming growth factor-β superfamily as a pivotal mechanism and therapeutic breakthrough. Transforming growth factor-β plays a crucial role in early joint cartilage formation and maintenance, promoting cartilage repair. However, post-joint formation, its protective effect weakens, leading to potential destructive consequences. This dual regulatory role is a current clinical treatment focus, necessitating further research to delineate its application scope for standardized protocols. Highly active transforming growth factor-β participates in the regulation of bone cells, osteoblasts, and osteoclasts under mechanical stress, and intervenes in the subsequent remodeling of bone microstructure. Specific inhibitors present potential targeted therapeutics, yet their safety and efficacy in clinical settings require refinement. Vascular proliferation may serve as a potential disruptive pathway in transforming growth factor-β-mediated cartilage degeneration and subchondral bone remodeling. Abnormal communication pathways can further disrupt the homeostasis of the microenvironment of osteochondral units, thereby accelerating key pathological progressions of osteoarthritis. Research on transforming growth factor-β in osteoarthritic contexts is comprehensive, holding broad clinical application prospects. Drugs related to transforming growth factor-β are in clinical trial phases, but addressing potential impacts on other tissues and precise control of targeted delivery are critical concerns. As research advances, there is optimism for innovative breakthroughs in slowing the progression of osteoarthritis in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND: Recent studies have shown that research on naringin anti-osteoporosis mostly stays in in vitro and in vivo experiments. Understanding the mechanism of related signaling pathways and the expression of related proteins and some specific genes is an important way to deeply understand naringin anti-osteoporosis. At present, traditional Chinese medicine has been confirmed to have a significant role in anti-osteoporosis. Naringin is one of the main active ingredients in Rhizoma Drynariae. Its effectiveness and mechanism of action against osteoporosis have been gradually recognized by scholars, and its clinical and basic research has been gradually emphasized. OBJECTIVE: To analyze and summarize the research progress of naringin in anti-osteoporosis in vitro and in vivo, thereby providing some ideas for the next step to study its related mechanism of action. METHODS: The relevant literatures included in CNKI and PubMed database were searched with the Chinese search terms of “naringin, osteoporosis, traditional Chinese medicine compound, pathogenesis, signaling pathway, bone marrow mesenchymal stem cells, osteoblasts, osteoclasts” in Chinese and English, respectively. The corresponding criteria were established according to the research needs, and finally 69 articles were included for review. RESULTS AND CONCLUSION: Naringin blocks the increase in the number of osteoclasts and adipocytes, the decrease in the number of osteocytes and osteocalcin (+) cells induced by fructose-rich diet, and promotes the secretion of Sema3A from osteoblasts and osteocytes, thereby enhancing local bone formation and inhibiting osteoclast production by activating the Wnt/β-catenin pathway. Naringin is an important way to induce autophagy of osteoblasts, but autophagy-related proteins participate in osteoblast differentiation and bone formation. Lack of autophagy in osteoblasts reduces mineralization and leads to an imbalance in the number of osteoblasts and osteoclasts, which results in bone loss and decreased bone density. The composite scaffold loaded with naringin can be used as a necessary carrier for bone defect repair and has excellent bone repair properties. Naringin can also accelerate the growth of new bone tissue by increasing the local contents of bone morphogenetic protein 2 and vascular endothelial growth factor. Naringin can regulate bone metabolism and inhibit oxidative stress via ERK, PI3K/Akt and Wnt signaling pathways to improve osteoporosis, which can play a good role in preventing and controlling the disease. However, the depth and breadth of the relevant research is insufficient. Based on the mechanism of the current study, we should investigate the specific mechanisms by which naringin regulates different pathways and inter-pathway interactions in the future, which will be beneficial to the multifaceted development of naringin used in the treatment of osteoporosis.. [ABSTRACT FROM AUTHOR]

BACKGROUND: As tissue engineering brings new hope to the worldwide problem of articular cartilage repair, the construction of light-curing 3D printed hydrogel scaffolds with biomimetic composition is of great significance for cartilage tissue engineering. OBJECTIVE: To construct a biomimetic methacryloylated hyaluronic acid/acellular Wharton’s jelly composite hydrogel scaffold by digital light processing 3D printing technology, and to evaluate its biocompatibility. METHODS: Wharton’s jelly was isolated and extracted from human umbilical cord, then decellulated, freeze-dried, ground into powder, and dissolved in PBS to prepare 50 g/L acellular Wharton’s jelly solution. Methylallylated hyaluronic acid was prepared, lyophilized and dissolved in PBS to prepare 50 g/L methylallylated hyaluronic acid solution. Acellular Wharton’s jelly solution was mixed with methacrylyacylated hyaluronic acid solution at a volume ratio of 1:1, and was used as bio-ink after adding photoinitiator. Methylacrylylated hyaluronic acid hydrogel scaffolds (labeled as HAMA hydrogel scaffolds) and methylacrylylated hyaluronic acid/acellular Wharton’s jelly gel scaffolds (labeled as HAMA/WJ hydrogel scaffolds) were prepared by digital light processing 3D printing technology, and the microstructure, swelling performance, biocompatibility, and cartilage differentiation performance of the scaffolds were characterized. RESULTS AND CONCLUSION: (1) Under scanning electron microscope, the two groups of scaffolds showed a three-dimensional network structure, and the fiber connection of HAMA/WJ hydrogel scaffold was more uniform. Both groups achieved swelling equilibrium within 10 hours, and the equilibrium swelling ratio of HAMA/WJ hydrogel scaffold was lower than that of HAMA hydrogel scaffold (P < 0.05). (2) CCK-8 assay showed that HAMA/WJ hydrogel scaffold could promote the proliferation of bone marrow mesenchymal stem cells compared with HAMA hydrogel scaffold. Dead/live staining showed that bone marrow mesenchymal stem cells grew well on the two groups of scaffolds, and the cells on the HAMA/WJ hydrogel scaffolds were evenly distributed and more cells were found. Phalloidine staining showed better adhesion and spread of bone marrow mesenchymal stem cells in HAMA/WJ hydrogel scaffold than in HAMA. (3) Bone marrow mesenchymal stem cells were inoculated into the two groups for chondrogenic induction culture. The results of qRT-PCR showed that the mRNA expressions of agglutinoglycan, SOX9 and type II collagen in the HAMA/WJ hydrogel scaffold group were higher than those in the HAMA hydrogel scaffold group (P < 0.05, P < 0.01). (4) These findings indicate that the digital light processing 3D bioprinting HAMA/WJ hydrogel scaffold can promote the proliferation, adhesion, and chondrogenic differentiation of bone marrow mesenchymal stem cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, some scholars in the field of tendon bone injury have attached stromal cell-derived factor 1 to tissue engineering scaffolds to promote tendon bone healing, and achieved good results. However, whether stromal cell-derived factor 1 promotes tendon bone healing mechanisms and participates in the repair of natural healing has not yet been defined. OBJECTIVE: To study the expression of stroma-cell derived factor 1 during tendon bone healing after rupture of the whole supraspinatus muscle of the rabbit rotator cuff and its migration effect and optimal in vitro migration promoting concentration on stem cells during tendon bone injury. METHODS: Totally 18 adult New Zealand rabbits were randomly selected to establish rotator cuff injury models, and an additional 3 rabbits were selected as blank controls. At 3, 5, 7, 14, 21, and 28 days after modeling, three rabbits were executed separately and the rabbits in the blank group were sacrificed. The tissues of tendon bone junction were taken and stored in a -80 ℃ refrigerator. The expression of stromal cell-derived factor 1 was detected by ELISA at each time point after injury. Mesenchymal stem cells were isolated from the bone marrow of young rabbit femur, cultured, and identified. Transwell assay was performed to verify the migration-promoting effect of stromal cell-derived factor 1 on stem cells and the optimal migration-promoting concentration in vitro. The stem cells cultured to P3 were co-cultured with BrdU and injected into the rabbit ear marginal vein, and immunohistochemical staining was used to verify whether the stem cells migrated to the injury site. RESULTS AND CONCLUSION: (1) Stromal cell-derived factor 1 gene expression was bimodal during rotator cuff tendon bone healing. Stromal cell-derived factor 1 gene expression increased significantly at 3 days post-injury (P < 0.01) and then decreased, reaching a minimum at 5 days post-injury. It increased again and reached a peak 14 days after injury (P < 0.01) and then decreased. (2) Cell immunohistochemical staining displayed that stem cells labeled with BrdU did migrate to the injury site. (3) The results of the transwell experiment exhibited that 60-80 ng/mL stromal cell-derived factor 1 had the best effect on promoting migration of stem cells, while a concentration of 200 ng/mL inhibited migration. (4) Stromal cell-derived factor 1 is involved in the healing of rotator cuff tendon bone during the inflammatory response phase and the proliferation phase. The mechanism of action may be to promote the migration of stem cells to the injury and their differentiation into various types of cells to promote repair. In addition, the pro-migration effect of stromal cell-derived factor 1 exists at a range of concentrations, beyond which it may act as an inhibitor. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bone marrow mesenchymal stem cells have been widely used to treat neurological diseases. However, due to limitations of the blood-brain barrier, low survival rate and differentiation rate of stem cells at damaged sites, the therapeutic effect is limited. OBJECTIVE: To investigate the effects of Shexiang Huangqi compound dripping pills on proliferation, migration and astrocyte differentiation of bone marrow mesenchymal stem cells. METHODS: Male SD rats were treated with Shexiang Huangqi compound dripping pills for 5 days after continuous gavage. Blood was collected from the abdominal aorta and serum was separated for later use. The effect of 5%, 10% and 20% drug-containing serum on the proliferation of bone marrow mesenchymal stem cells was detected by CCK-8 assay. The effect of 10% drug-containing serum on lateral migration of bone marrow mesenchymal stem cells was observed by scratch test. Bone marrow mesenchymal stem cells were cultured in Transwell cells. The effects of 10% drug-containing serum on longitudinal migration of bone marrow mesenchymal stem cells were observed by crystal violet staining and DAPI nuclear staining. Differentiation of bone marrow mesenchymal stem cells into astrocytes was observed by inducing solution with 10% drug-containing serum or co-culture with astrocytes. RESULTS AND CONCLUSION: (1) 10% and 20% drug-containing serum promoted cell proliferation more significantly on days 2 and 3, and there was no statistical difference between the two concentrations. (2) At 30 and 48 hours, bone marrow mesenchymal stem cell migration in 10% drug-containing serum group was significantly higher than that in the control group. (3) The number of bone marrow mesenchymal stem cells filtered through Transwell cells in 10% drug-containing serum group was higher than that in the control group. (4) 10% drug-containing serum might promote the differentiation of bone marrow mesenchymal stem cells to astrocytes, but the differentiation effect was weak, and astrocytes might further promote the differentiation of bone marrow mesenchymal stem cells into astrocytes induced by drug-containing serum. (5) The results exhibited that the 10% drug-containing serum could promote the proliferation and migration of bone marrow mesenchymal stem cells in vitro. Co-culture with astrocytes may promote the differentiation of bone marrow mesenchymal stem cells towards astrocytes. [ABSTRACT FROM AUTHOR]

BACKGROUND: The implant osseointegration rate of patients with diabetes is low, and the failure rate is high, which seriously affects the quality of life. It is urgent to improve the implant osseointegration of patients with diabetes by effective means to elevate the success rate. Exploring the effect of berberine on the osteogenic differentiation of bone marrow mesenchymal stem cells under a high-glucose environment and its specific mechanism will provide effective theoretical support for solving the above problems. OBJECTIVE: To explore the effect of natural extract berberine on the osteogenic differentiation of rat bone marrow mesenchymal stem cells under the high)glucose microenvironment. METHODS: Bone marrow mesenchymal stem cells of SD rats were cultured by the whole bone marrow adherence method. CCK-8 assay was used to detect the effects of different concentrations of berberine on the proliferation of bone marrow mesenchymal stem cells under the high-glucose environment and to screen out the optimal berberine concentration. The expressions of Runx2 and Osx were detected by alkaline phosphatase activity, alicarin red staining and PCR to determine the effect of berberine on osteogenic differentiation of bone marrow mesymal stem cells under the high-glucose environment. To further explore the underlying mechanism, we introduced the AMPK-specific inhibitor Dorsomorphin and used a DCFH-DA reactive oxygen species fluorescent probe to examine reactive oxygen species levels. The p-AMPK expression was also determined by western blot assay. RESULTS AND CONCLUSION: (1) 10 µmol/L was the optimal concentration of berberine to promote bone marrow mesenchymal stem cell proliferation. (2) Alberberine promoted alkaline phosphatase viability of bone marrow mesenchymal stem cells and mineralized nodule formation in a high-glucose microenvironment. (3) Alberberine promoted the expression of Runx2 and OSx in a high-glucose microenvironment. (4) Alberensine effectively inhibited the reactive oxygen species level of bone marrow mesenchymal stem cells in a high-glucose environment. (5) The effects of berberine on promoting bone marrow mesenchymal stem cell osteogenesis and inhibition of reactive oxygen species were reversed by the AMPK inhibitor. (6) Berberine activated AMPK and promoted p-AMPK expression. (7) The above results indicate that berberine (10 µmol/L) promotes the osteogenic differentiation of bone marrow mesenchymal stem cells in a high-glucose environment by activating AMPK and reducing intracellular reactive oxygen species levels. [ABSTRACT FROM AUTHOR]

Diabetic osteoporosis (DO) presents significant clinical challenges. This study aimed to investigate the potential of magnetic nanoparticle-enhanced extracellular vesicles (GMNPE-EVs) derived from bone marrow mesenchymal stem cells (BMSCs) to deliver miR-15b-5p, thereby targeting and downregulating glial fibrillary acidic protein (GFAP) expression in rat DO models. Data was sourced from DO-related RNA-seq datasets combined with GEO and GeneCards databases. Rat primary BMSCs, bone marrow-derived macrophages (BMMs), and osteoclasts were isolated and cultured. EVs were separated, and GMNPE targeting EVs were synthesized. Bioinformatic analysis revealed a high GFAP expression in DO-related RNA-seq and GSE26168 datasets for disease models. Experimental results confirmed elevated GFAP in rat DO bone tissues, promoting osteoclast differentiation. miR-15b-5p was identified as a GFAP inhibitor, but was significantly downregulated in DO and enriched in BMSC-derived EVs. In vitro experiments showed that GMNPE-EVs could transfer miR-15b-5p to osteoclasts, downregulating GFAP and inhibiting osteoclast differentiation. In vivo tests confirmed the therapeutic potential of this approach in alleviating rat DO. Collectively, GMNPE-EVs can effectively deliver miR-15b-5p to osteoclasts, downregulating GFAP expression, and hence, offering a therapeutic strategy for rat DO. [ABSTRACT FROM AUTHOR]

BACKGROUND: Oral and maxillofacial bone tissue defects can seriously affect the physical and mental health of patients. When bone defects occur in diabetic patients, bone metabolism disorders caused by abnormal blood sugar make it more difficult to repair and treat. OBJECTIVE: To attempt to apply AOPDM1, a polypeptide with potential bioactivity to the osteogenic treatment of diabetic patients. METHODS: In normal or high-glucose environment, different concentrations of AOPDM1 were used to interfere with mouse bone marrow mesenchymal stem cells, and cell proliferation, alkaline phosphatase activity, mineralization nodules formation and osteogenic differentiation gene expression were detected. The polycaprolactone scaffold was prepared by electrospinning technology, and the scaffold was modified by polydopamine to prepare the polycaprolactonepolydopamine composite scaffold. Finally, the scaffolds were placed in AOPDM1 solution to prepare polycaprolactone-polydopamine-AOPDM1 scaffolds. The water contact angle and mechanical properties of the scaffolds were tested in the three groups. In normal or high-glucose environment, the three groups of scaffolds were co-cultured with mouse bone marrow mesenchymal stem cells, respectively, and cell adhesion, alkaline phosphatase activity and osteopontin expression were detected. RESULTS AND CONCLUSION: (1) Compared with normal environment, high-glucose environment inhibited the proliferation of bone marrow mesenchymal stem cells. In the same environment, AOPDM1 could promote the proliferation of mouse bone marrow mesenchymal stem cells. When AOPDM1 concentration was the same, alkaline phosphatase activity, mineralization ability and mRNA expression of type I collagen, osteopontin, alkaline phosphatase, and Runx2 of bone marrow mesenchymal stem cells were decreased in high-glucose environment compared with normal environment. Under the same environment, AOPDM1 could improve the alkaline phosphatase activity, mineralization ability, and mRNA expression of type I collagen, osteopontin, alkaline phosphatase and Runx2 of bone marrow mesenchymal stem cells. (2) The hydrophilicity of polycaprolactone-polydopamine scaffold and polycaprolactone-polydopamineAOPDM1 scaffold was higher than that of polycaprolactone scaffold (P < 0.001), and there was no significant difference in tensile strength and elastic modulus among the three groups (P > 0.05). Compared with the other two groups of scaffolds, the cells on the polycaprolactone-polydopamine-AOPDM1 scaffold had better adhesion morphology. When the scaffolds were identical, compared with normal environment, high-glucose environment inhibited alkaline phosphatase activity and osteopontin expression of bone marrow mesenchymal stem cells. When the environment was the same, the alkaline phosphatase activity and osteopontin expression of bone marrow mesenchymal stem cells on the polycaprolactone-polydopamine-AOPDM1 scaffold were higher than those on the other two scaffolds. (3) The above results prove that polycaprolactone-polydopamine-AOPDM composite scaffold can promote the osteogenic properties of bone marrow mesenchymal stem cells in high-glucose environment. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cell (MSC)-derived exosomes are considered as alternative to cell therapy in various diseases. This study aimed to understand the effect of bone marrow MSC-derived exosomes (BMMSC-exos) on spinal cord injury (SCI) and to unveil its regulatory mechanism on ferroptosis. Exosomes were isolated from BMMSCs and the uptake of BMMSCs-exos by PC12 cells was determined using PKH67 staining. The effect of BMMSC-exos on SCI in rats was studied by evaluating pathological changes of spinal cord tissues, inflammatory cytokines, and ferroptosis-related proteins. Transcriptome sequencing was used to discover the differential expressed genes (DEGs) between SCI rats and BMMSC-exos-treated rats followed by functional enrichment analyses. The effect of BMMSC-exos on ferroptosis and interleukin 17 (IL-17) pathway was evaluated in SCI rats and oxygen–glucose deprivation (OGD)-treated PC12 cells. The results showed that particles extracted from BMMSCs were exosomes that could be taken up by PC12 cells. BMMSC-exos treatment ameliorated injuries of spinal cord, suppressed the accumulation of Fe2+, malondialdehyde (MDA), and reactive oxygen species (ROS), with the elevated glutathione (GSH). Also, BMMSC-exos downregulated the expression of acyl-CoA synthetase long chain family member 4 (ACSL4) and upregulated glutathione peroxidase 4 (GPX4) and cysteine/glutamate antiporter xCT. A total of 110 DEGs were discovered and they were mainly enriched in IL-17 signaling pathway. Further in vitro and in vivo experiments showed that BMMSC-exos inactivated IL-17 pathway. BMMSC-exos promote the recovery of SCI and inhibit ferroptosis by inhibiting the IL-17 pathway, which provides BMMSC-exos as an alternative to the management of SCI. [ABSTRACT FROM AUTHOR]

IntroductionOsteosarcoma is the most common primary bone tumor. Patients require chemotherapy drugs with high-targeting ability and low off-target toxicity to improve their survival. Exosomes are biological vesicles that mediate long-distance communication between cells and naturally target their source sites. Exosomes derived from bone marrow mesenchymal stem cells (BMSCs) naturally target bone tumor sites, suggesting their potential as effective anti-tumor therapy vectors. In this study, we evaluated the potential of BMSC-derived exosomes in targeting osteosarcoma and serving as a carrier for doxorubicin (DOX).MethodsWe isolated exosomes from human BMSCs and synthesized hybrid exosomes (HEs) by fusing these exosomes with liposomes. These HEs were loaded with DOX to produce a novel drug, HE/DOX.ResultsWe confirmed the successful synthesis of HE/DOX using fluorescence spectroscopy and estimated its size to be 151.1 ± 10.2 nm. HEs expressed the known exosomal proteins ALIX, CD63, and TSG101. Under acidic conditions similar to those observed in the tumor microenvironment, the drug release from HE/DOX was enhanced. In osteosarcoma cell lines and in a mouse osteosarcoma model, HE/DOX exhibited stronger tumor-inhibitory effects than free DOX.ConclusionsOur study demonstrates that BMSC-derived exosomes could effectively target osteosarcoma. Furthermore, HEs can serve as effective carriers of DOX, enabling the treatment of osteosarcoma. These findings highlight a promising direction for tumor-targeted therapy.

Abstract Background Exosomes (Exos) are involved in the therapeutic effects of bone marrow mesenchymal stem cells (BMSCs) on heart failure (HF). We investigated the molecular mechanisms underlying the involvement of BMSC-Exos in ferroptosis on HF. Methods A rat model of HF and cellular model of hypoxia were established. BMSC-Exos were injected into model rats or co-cultured with model cells. In model rats, the cardiac function (echocardiography), oxidative stress (commercial kits), pathological damage (HE staining), fibrosis (MASSON staining), iron deposition (Prussian blue staining), and cell apoptosis (TUNEL staining) were examined. Viability (cell counting kit-8; CCK-8), cell cycle (flow cytometry), oxidative stress, and Fe2+ levels were detected in the model cells. GAS5, UL3, YAP, and TAZ expression were detected using qRT-PCR, western blotting, and immunohistochemistry analyses. Results BMSC-Exos restored cardiac function and inhibited oxidative stress, apoptosis, pathological damage, fibrosis, and iron deposition in myocardial tissues of HF rats. In hypoxic cells, BMSC-Exos increased cell viability, decreased the number of G1 phase cells, decreased Fe2+ levels, and inhibited oxidative stress. Ferrostatin-1 (a ferroptosis inhibitor) exhibited a synergistic effect with BMSC-Exos. Additionally, GAS5 was upregulated in BMSC-Exos, further upregulating its target UL3 and Hippo pathway effectors (YAP and TAZ). The relieving effects of BMSC-Exos on HF or hypoxia-induced injury were enhanced by GAS5 overexpression, but weakened by UL3 silencing or verteporfin (a YAP inhibitor). Conclusions GAS5-harbouring BMSC-Exos inhibited ferroptosis by regulating the UL3/Hippo pathway, contributing to HF remission in vivo and in vitro.

Abstract Background A triplet chemotherapy regimen of docetaxel, cisplatin, and 5-fluorouracil (TPF) is used to treat head and neck squamous cell carcinoma; however, it is toxic to bone marrow mesenchymal stem cells (BMSCs). We previously demonstrated that Ganoderma spore lipid (GSL) protect BMSCs against cyclophosphamide toxicity. In this study, we investigated the protective effects of GSL against TPF-induced BMSCs and hematopoietic damage. Methods BMSCs and C57BL/6 mice were divided into control, TPF, co-treatment (simultaneously treated with GSL and TPF for 2 days), and pre-treatment (treated with GSL for 7 days before 2 days of TPF treatment) groups. In vitro, morphology, phenotype, proliferation, senescence, apoptosis, reactive oxygen species (ROS), and differentiation of BMSCs were evaluated. In vivo, peripheral platelets (PLTs) and white blood cells (WBCs) from mouse venous blood were quantified. Bone marrow cells were isolated for hematopoietic colony-forming examination. Results In vitro, GSL significantly alleviated TPF-induced damage to BMSCs compared with the TPF group, recovering their morphology, phenotype, proliferation, and differentiation capacity (p

HypothesisWe hypothesized that Lomecel-B, an allogeneic medicinal signaling cell (MSC) therapeutic candidate for Alzheimer's disease (AD), is safe and potentially disease-modifying via pleiotropic mechanisms of action.Key predictionsWe prospectively tested the predictions that Lomecel-B administration to mild AD patients is safe (primary endpoint) and would provide multiple exploratory indications of potential efficacy in clinical and biomarker domains (prespecified secondary/exploratory endpoints).Strategy and key resultsMild AD patient received a single infusion of low- or high-dose Lomecel-B, or placebo, in a double-blind, randomized, phase I trial. The primary safety endpoint was met. Fluid-based and imaging biomarkers indicated significant improvement in the Lomecel-B arms versus placebo. The low-dose Lomecel-B arm showed significant improvements versus placebo on neurocognitive and other assessments.InterpretationOur results support the safety of Lomecel-B for AD, suggest clinical potential, and provide mechanistic insights. This early-stage study provides important exploratory information for larger efficacy-powered clinical trials.

Background: Exosomes (Exos) are involved in the therapeutic effects of bone marrow mesenchymal stem cells (BMSCs) on heart failure (HF). We investigated the molecular mechanisms underlying the involvement of BMSC-Exos in ferroptosis on HF. Methods: A rat model of HF and cellular model of hypoxia were established. BMSC-Exos were injected into model rats or co-cultured with model cells. In model rats, the cardiac function (echocardiography), oxidative stress (commercial kits), pathological damage (HE staining), fibrosis (MASSON staining), iron deposition (Prussian blue staining), and cell apoptosis (TUNEL staining) were examined. Viability (cell counting kit-8; CCK-8), cell cycle (flow cytometry), oxidative stress, and Fe2+ levels were detected in the model cells. GAS5, UL3, YAP, and TAZ expression were detected using qRT-PCR, western blotting, and immunohistochemistry analyses. Results: BMSC-Exos restored cardiac function and inhibited oxidative stress, apoptosis, pathological damage, fibrosis, and iron deposition in myocardial tissues of HF rats. In hypoxic cells, BMSC-Exos increased cell viability, decreased the number of G1 phase cells, decreased Fe2+ levels, and inhibited oxidative stress. Ferrostatin-1 (a ferroptosis inhibitor) exhibited a synergistic effect with BMSC-Exos. Additionally, GAS5 was upregulated in BMSC-Exos, further upregulating its target UL3 and Hippo pathway effectors (YAP and TAZ). The relieving effects of BMSC-Exos on HF or hypoxia-induced injury were enhanced by GAS5 overexpression, but weakened by UL3 silencing or verteporfin (a YAP inhibitor). Conclusions: GAS5-harbouring BMSC-Exos inhibited ferroptosis by regulating the UL3/Hippo pathway, contributing to HF remission in vivo and in vitro. [ABSTRACT FROM AUTHOR]

Alterations to the human organism that are brought about by aging are comprehensive and detrimental. Of these, an imbalance in bone homeostasis is a major outward manifestation of aging. In older adults, the decreased osteogenic activity of bone marrow mesenchymal stem cells and the inhibition of bone marrow mesenchymal stem cell differentiation lead to decreased bone mass, increased risk of fracture, and impaired bone injury healing. In the past decades, numerous studies have reported the epigenetic alterations that occur during aging, such as decreased core histones, altered DNA methylation patterns, and abnormalities in noncoding RNAs, which ultimately lead to genomic abnormalities and affect the expression of downstream signaling osteoporosis treatment and promoter of fracture healing in older adults. The current review summarizes the impact of epigenetic regulation mechanisms on age‐related bone homeostasis imbalance. [ABSTRACT FROM AUTHOR]

Objective To explore effects of MCF-7 breast cancer cell conditioned medium on proliferation, apoptosis and migration of bone marrow mesenchymal stem cells (BMSC) and its molecular mechanism. Methods BMSC cultured under normal environment was used as the control group. BMSC cultured with MCF-7 cell conditioned medium was selected as the MCF-7 conditioned medium group. The MCF-7 conditioned medium group supplemented with 10 nmol/L GSK690693 (Akt inhibitor) was used as the Akt inhibitor group. The MCF-7 conditioned medium group added with 10 µmol/L Reparixin (CXCR1/2 inhibitor) was used as the CXCR1/2 inhibitor group. BMSC proliferation was detected by MTT assay. Annexin V-FITC/PI double labeled flow cytometry was used to detect BMSC apoptosis rate in each group. Transwell cell migration assay was used to detect the migration ability of BMSC in each group. The contents of interleukin (IL)-8 protein in two kinds of cell culture supernatant and MCF-7 cell conditioned medium were detected by enzyme-linked immunosorbent assay. The protein expression levels of protein kinase B (Akt)/phosphorylated Akt (p-Akt) and mammalian target of rapamycin (mTOR)/phosphorylated mTOR (p-mTOR) in BMSC of each group were detected by Western blot assay. Results Compared with the control group, cell proliferation level, migration number and the relative expression levels of p-Akt, p-mTOR protein of BMSC were increased in the MCF-7 conditioned medium group, and the apoptosis rate was decreased (P＜0.05). Compared with the MCF-7 conditioned medium group, cell proliferation level, migration number and the relative expression levels of p-Akt, p-mTOR protein of BMSC were decreased in the CXCR1/2 inhibitor group and the Akt inhibitor group, and the apoptosis rate was increased (P＜0.05). The contents of IL-8 protein in MCF-7 cell conditioned medium and MCF-7 culture supernatant were higher than that in the BMSC culture supernatant (P＜0.05). Conclusion MCF-7 cell conditioned medium promotes BMSC proliferation and migration and inhibits BMSC apoptosis by activating Akt-mTOR signaling pathway, in which IL-8-CXCR1/2 axis plays a key role. [ABSTRACT FROM AUTHOR]

Background: A triplet chemotherapy regimen of docetaxel, cisplatin, and 5-fluorouracil (TPF) is used to treat head and neck squamous cell carcinoma; however, it is toxic to bone marrow mesenchymal stem cells (BMSCs). We previously demonstrated that Ganoderma spore lipid (GSL) protect BMSCs against cyclophosphamide toxicity. In this study, we investigated the protective effects of GSL against TPF-induced BMSCs and hematopoietic damage. Methods: BMSCs and C57BL/6 mice were divided into control, TPF, co-treatment (simultaneously treated with GSL and TPF for 2 days), and pre-treatment (treated with GSL for 7 days before 2 days of TPF treatment) groups. In vitro, morphology, phenotype, proliferation, senescence, apoptosis, reactive oxygen species (ROS), and differentiation of BMSCs were evaluated. In vivo, peripheral platelets (PLTs) and white blood cells (WBCs) from mouse venous blood were quantified. Bone marrow cells were isolated for hematopoietic colony-forming examination. Results: In vitro, GSL significantly alleviated TPF-induced damage to BMSCs compared with the TPF group, recovering their morphology, phenotype, proliferation, and differentiation capacity (p < 0.05). Annexin V/PI and senescence-associated β-galactosidase staining showed that GSL inhibited apoptosis and delayed senescence in TPF-treated BMSCs (p < 0.05). GSL downregulated the expression of caspase-3 and reduced ROS formation (p < 0.05). In vivo, GSL restored the number of peripheral PLTs and WBCs and protected the colony-forming capacity of bone marrow cells (p < 0.05). Conclusions: GSL efficiently protected BMSCs from damage caused by TPF and recovered hematopoiesis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Currently, the dura mater is clinically repaired using autologous tissue or materials such as gelatin sponge, but all of them have their inherent defects. Therefore, there is an urgent need for a biomaterial that can promote dural repair. OBJECTIVE: The two-sided anisotropic electrospun membrane was constructed by using directional electrospinning technology and collagen self-assembly technology, and was used as a carrier for bone marrow mesenchymal stem cells to investigate various physicochemical properties and biological characteristics of the artificial dura mater. METHODS: Ordered polylactic acid electrospun fibers with double-sided (collagen protein on one side and polylactic acid on the other side) anisotropic electrospun membranes (collagen group), disordered polylactic acid electrospun membranes (disordered fiber group), and ordered oriented polylactic acid electrospun membranes (ordered fiber group) were prepared by electrospinning technique as well as collagen self-assembly technique. Scanning electron microscopy, mechanical stretching, water contact angle testing, and degradation experiments were used to characterize the physicochemical properties of the electrospun membranes. Electrospun membranes in the collagen group (bone marrow mesenchymal stem cells were inoculated on the collagen surface to obtain the stem cell-engineered electrospun membranes), disordered fiber group and ordered fiber group were cocultured with bone marrow mesenchymal stem cells. The biocompatibility of electrospun membranes was evaluated using CCK-8 assay and live/dead staining. Integrin β1 immunofluorescence staining was used to evaluate the adhesion characteristics of electrospun membranes. The stem cell-engineered electrospun membrane and the electrospun membrane in the collagen group were cocultured with bone marrow macrophages respectively. Immunomodulatory properties were assessed by detecting the expression of inflammation-related genes using inducible nitric oxide synthase (M1 type), CD206 (M2 type) immunofluorescence staining, and qRT-PCR. RESULTS AND CONCLUSION: (1) The oriented electrospun fiber membrane could mimic the structure of the longitudinally aligned natural dura mater, and the addition of collagen increased the hydrophilicity of the fiber membrane by about 2-fold and the mechanical properties by 1.2-fold. (2) When cocultured with bone marrow mesenchymal stem cells, CCK-8 assay and live/dead staining suggested that the cellular bioactivity in the collagen group was significantly higher than that in the disordered fiber group and ordered fiber group. Immunofluorescence staining revealed that the expression of integrin β1 in the collagen group was about 2.6 times higher than that of the disordered and ordered fiber groups, and the cell spreading morphology was good. (3) When cocultured with bone marrow macrophages, immunofluorescence staining exhibited that the fluorescence intensity of M1 type macrophages in the stem cell-engineered electrospun membrane group was lower than that in the collagen group (P < 0.01), and the fluorescence intensity of M2 type macrophages was higher than that in the collagen group (P < 0.01). qRT-PCR demonstrated that proinflammatory gene tumor necrosis factor α and interleukin-1β mRNA expression in the stem cell-engineered electrospun membrane group was lower than that of the collagen group (P < 0.001); anti-inflammatory genes such as interleukin-10 and transforming growth factor β mRNA expressions were higher than those in the collagen group (P < 0.001). (4) The above results suggest that the stem cellengineered amphipathic artificial dura mimics the directional structure of normal dura, with the inner surface facilitating cell growth and adhesion and the outer edge avoiding tissue adhesion, while the polarization of macrophages to the M2 subtype is promoted and the local inflammatory microenvironment is regulated through the mesenchymal stem cell paracrine component. [ABSTRACT FROM AUTHOR]

BACKGROUND: Medical titanium and titanium alloy have achieved good therapeutic effects in clinical applications, but there are still some phenomena such as peri-implant inflammation, loosening and shedding. OBJECTIVE: To explore the physicochemical properties of graphene oxide coating materials and their effects on bone marrow mesenchymal stem cells. METHODS: (1) Hydroxyapatite coating and graphene oxide/hydroxyapatite composite coating were prepared on a titanium surface by electrochemical deposition. The surface morphology, phase structure, functional groups, elemental composition and surface hydrophilicity of the coating were analyzed by scanning electron microscopy, X-ray energy dispersion spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy, and contact angle measurement instrument. (2) Mouse bone marrow mesenchymal stem cells were isolated and cultured and inoculated on pure titanium, hydroxyapatite coating and graphene oxide/hydroxyapatite composite coating, respectively. CCK-8 assay and scanning electron microscopy were used to evaluate the proliferation, morphology and growth status of the coated cells. RESULTS AND CONCLUSION: (1) Scanning electron microscopy and X-ray energy dispersion spectra showed that the surface of graphene oxide/hydroxyapatite composite coating was more flat, compact and uniform than that of hydroxyapatite coating and pure titanium. X-ray photoelectron spectroscopy, X-ray diffraction and Raman spectroscopy showed that hydroxyapatite coating and graphene oxide/hydroxyapatite composite coating were successfully prepared on the surface of the titanium sheet. The hydrophilicity of graphene oxide/hydroxyapatite composite coating was better than that of hydroxyapatite coating and pure titanium. (2) CCK-8 assay showed that the number of bone marrow mesenchymal stem cells on the surface of the three groups increased with the extension of co-culture time. On days 1, 4, and 7, the proliferative absorbance of the cells on the graphene oxide/hydroxyapatite composite coating was higher than that on hydroxyapatite coating and pure titanium (P < 0.000 1). Scanning electron microscopy after 4 days of co-culture showed that bone marrow mesenchymal stem cells on the surface of the three groups of materials were fusiform. The cells on the surface of graphene oxide/hydroxyapatite composite coating showed good tensile properties and were polygonal. Multiple antennae could be seen attached to the coating surface at the edge of the cells, and the elongation of the filamentous foot on the surface was more than that on pure titanium and hydroxyapatite coatings. (3) The results show that graphene oxide/ hydroxyapatite composite coating material is a kind of coating material with excellent physicochemical and biological properties. [ABSTRACT FROM AUTHOR]

To investigate the ability of sulfonated polyetheretherketone (SPEEK) to promote the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and compare the effects of different degrees of sulfonation (DS), SPEEK was made with two different DS. The L-SPEEK group had a lower DS, while the H-SPEEK group had a higher DS. The physicochemical properties of both species were evaluated by scanning electron microscopy (SEM), capitilize Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Then, proliferation and osteogenic differentiation between the two groups and with pure polyetheretherketone (PEEK) were compared after surface inoculation of bone marrow mesenchymal stem cells (BMSCs). Scanning electron microscopy (SEM) revealed that the surface of the PEEK substrates could be smooth or coarse, and the degree of roughness increased with increasing sulfonation. FTIR spectroscopy showed that both the L-SPEEK and H-SPEEK samples contained sulfonic acid. TGA and XRD revealed that the components in the two groups were the same, but the intensities were different. After BMSC inoculation, a CCK8 assay revealed that the cells proliferated more on the H-SPEEK surface and little on the L-SPEEK surface compared with the PEEK surface. Then, osteogenic differentiation was verified by immunofluorescence staining for OCN and Runx2, which indicated that H-SPEEK had the greatest effect on improving differentiation. The results of alizarin red staining (ARS) and alkaline phosphatase staining (APS) also revealed this trend. Sulfonation can change the microsurface of PEEK, which can improve both BMSC proliferation and osteogenic differentiation.

With rising society stress, depression-induced osteoporosis is increasing. However, the mechanism involved is unclear. In this study, we explored the effect of plasma exosomal miRNAs on bone marrow mesenchymal stem cell (BMSC) osteogenic differentiation in a chronic unpredictable mild stress (CUMS)-induced depression rat model. After 12 weeks of CUMS-induced depression, the pathological changes in the bone tissue and markers of osteogenic differentiation were tested by micro-computed tomography, hematoxylin-eosin staining, and quantitative real-time reverse transcription PCR (qRT-PCR). Plasma exosomes from rats were isolated and co-incubated with BMSCs for 14 d to detect the effect on osteogenic markers. Next-generation sequencing identified the miRNAs in the plasma exosomes, and the differential miRNAs were analyzed and verified by qRT-PCR. BMSCs were infected with lentivirus to upregulate miRNA-30a-5p and incubated in a medium that induced osteogenic differentiation for 14 d. The effect of miR-30a-5p on osteogenic differentiation was determined by qPCR and alizarin red staining. CUMS-induced depression rat model was established successfully, and exhibited reduced bone mass and damaged bone microstructure compared to that of the controls. The observed pathological changes suggested the occurrence of osteoporosis in the CUMS group, and the mRNA expression of osteogenic markers was also significantly reduced. Incubation of BMSCs with plasma exosomes from the CUMS group for 14 d resulted in a significant decrease in the expression of osteogenic markers. Twenty-five differentially expressed miRNAs in plasma exosomes were identified and upregulation of miR-30a-5p was observed to significantly inhibit the expression of osteogenic markers in BMSCs. Our findings contributed to a comprehensive understanding of the mechanism of osteoporosis caused by depression, and demonstrated the potential of miR-30a-5p as a novel biomarker or therapeutic target for the treatment of osteoporosis.

Abstract Background Osteoarthritis is a chronic disease mainly involving the damage of articular cartilage and the whole articular tissue, which is the main cause of disability in the elderly. To explore more effective treatment measures, this study analyzed the regulatory role and molecular mechanism of lncRNA LINC00665 (LINC00665) in the chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), providing a valuable theoretical basis for the pathogenesis and patient treatment of osteoarthritis. Methods Osteoarthritis tissues and healthy tissues were obtained from 52 patients with osteoarthritis and 34 amputated patients without osteoarthritis, and the levels of LINC00665 and miR-214-3p were assessed by RT-qPCR. BMSCs were cultured and induced chondrogenic differentiation. The proliferation ability of BMSCs was detected by CCK-8 method, and the apoptosis level of BMSCs was evaluated by flow cytometry. The content of proteoglycan-glycosaminoglycan (GAG) in cartilage matrix was determined by Alcian blue staining. In addition, the binding relationship between LINC00665 and miR-214-3p was verified by luciferase reporter assay, and the molecular mechanism was further analyzed. Results In osteoarthritis tissues, LINC00665 was elevated and miR-214-3p was down-regulated. With the chondrogenic differentiation of BMSCs, the level of GAG increased, and LINC00665 expression gradually decreased, while miR-214-3p level was on the contrary. After transfection of pcDNA3.1-LINC00665 in BMSCs, cell proliferation capacity was decreased, apoptosis rate was increased, and GAG content was reduced. Moreover, LINC00665 sponged miR-214-3p and negatively regulate its expression. Transfection of pcDNA3.1-LINC00665-miR-214-3p mimic changed the regulation of pcDNA3.1-LINC00665 on the viability and chondrogenic differentiation of BMSCs. Conclusions Overexpression of lncRNA LINC00665 inhibited the proliferation and chondrogenic differentiation of BMSCs by targeting miR-214-3p. The LINC00665/miR-214-3p axis may improve joint damage and alleviate the progression of osteoarthritis.

Introduction: Bones are easily damaged. Biomimetic scaffolds are involved in tissue engineering. This study explored polydopamine (PDA)-coated poly lactic-co-glycolic acid (PLGA)-magnesium oxide (MgO) scaffold properties and its effects on bone marrow mesenchymal stem cells (BMSCs) osteogenic differentiation. Methods: PLGA/MgO scaffolds were prepared by low-temperature 3D printing technology and PDA coatings were prepared by immersion method. Scaffold structure was observed by scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS), fourier transform infrared spectrometer (FTIR). Scaffold hydrophilicity, compressive/elastic modulus, and degradation rates were analyzed by water contact angle measurement, mechanical tests, and simulated-body fluid immersion. Rat BMSCs were cultured in scaffold extract. Cell activity on days 1, 3, and 7 was detected by MTT. Cells were induced by osteogenic differentiation, followed by evaluation of alkaline phosphatase (ALP) activity on days 3, 7, and 14 of induction and Osteocalcin, Osteocalcin, and Collagen I expressions. Results: The prepared PLGA/MgO scaffolds had dense microparticles. With the increase of MgO contents, the hydrophilicity was enhanced, scaffold degradation rate was accelerated, magnesium ion release rate and scaffold extract pH value were increased, and cytotoxicity was less when magnesium mass ratio was less than 10%. Compared with other scaffolds, compressive and elastic modulus of PLGA/MgO (10%) scaffolds were increased; BMSCs incubated with PLGA/MgO (10%) scaffold extract had higher ALP activity and Osteocalcin, Osteopontin, and Collagen I expressions. PDA coating was prepared in PLGA/MgO (10%) scaffolds and the mechanical properties were not affected. PLGA/MgO (10%)/PDA scaffolds had better hydrophilicity and biocompatibility and promoted BMSC osteogenic differentiation. Conclusion: Low-temperature 3D printing PLGA/MgO (10%)/PDA scaffolds had good hydrophilicity and biocompatibility, and were conducive to BMSC osteogenic differentiation.

AbstractContext Wen-Shen-Tong-Luo-Zhi-Tong (WSTLZT) Decoction is a Chinese prescription with antiosteoporosis effects, especially in patients with abnormal lipid metabolism.Objective To explore the effect and mechanism of WSTLZT on osteoporosis (OP) through adipocyte-derived exosomes.Materials and methods Adipocyte-derived exosomes with or without WSTLZT treated were identified by transmission electron microscopy, nanoparticle tracking analysis (NTA) and western blotting (WB). Co-culture experiments for bone marrow mesenchymal stem cells (BMSCs) and exosomes were performed to examine the uptake and effect of exosome in osteogenesis and adipogenic differentiation of BMSC. MicroRNA profiles, luciferase and IP were used for exploring specific mechanisms of exosome on BMSC. In vivo, 80 Balb/c mice were randomly divided into four groups: Sham, Ovx, Exo (30 μg exosomes), Exo-WSTLZT (30 μg WSTLZT-exosomes), tail vein injection every week. After 12 weeks, the bone microstructure and marrow fat distribution were analysed by micro-CT.Results ALP, Alizarin red and Oil red staining showed that WSTLZT-induced exosomes from adipocyte can regulate osteoblastic and adipogenic differentiation of BMSC. MicroRNA profiles observed that WSTLZT treatment resulted in 87 differentially expressed miRNAs (p

Treatment of articular cartilage remains a great challenge due to its limited self-repair capability. In tissue engineering, a scaffold with both mechanical strength and regenerative capacity has been highly desired. This study developed a double-network scaffold based on natural biomaterials of silk fibroin (SF) and methacrylated hyaluronic acid (MAHA) using three-dimensional (3D) printing technology. Structural and mechanical characteristics of the scaffold was first investigated. To enhance its ability of recruiting endogenous bone marrow mesenchymal stem cells (BMSCs), the scaffold was conjugated with a proven BMSC-specific-affinity peptide E7, and its biocompatibility and capacity of cell recruitment were assessed in vitro. Animal experiments were conducted to evaluate cartilage regeneration after transplantation of the described scaffolds. The SF/HA scaffolds exhibited a hierarchical macro-microporous structure with ideal mechanical properties, and offered a 3D spatial microenvironment for cell migration and proliferation. In vitro experiments demonstrated excellent biocompatibility of the scaffolds to support BMSCs proliferation, differentiation, and extracellular matrix production. In vivo, superior capacity of cartilage regeneration was displayed by the SF/MAHA + E7 scaffold as compared with microfracture and unconjugated SF/MAHA scaffold based on macroscopic, histologic and imaging evaluation. In conclusion, this structurally and functionally optimized SF/MAHA + E7 scaffold may provide a promising approach to repair articular cartilage lesions in situ.

Bone mesenchymal stem cell (BMSC)-derived exosome (BMSC-Exo) could be a treatment method for ischemic injury. In ischemic cerebrovascular disease (IC), microglia is pivotal in neuronal damage and remodeling. This study explores the mechanisms of BMSC-Exo miR-148b-3p in regulating oxygen-glucose deprivation/reoxygenation (OGD/R)-induced human microglial clone 3 (HMC3) cell activation. Transmission electron microscopy (TEM) and qNano were used to assess BMSC-Exo features. The functions of BMSC-Exo miR-148 b-3p in OGD/R-induced HMC3 cell activation were explored via MTT assay, flow cytometry, scratch, transwell, and enzyme-linked immunosorbent assay (ELISA) assays. A dual-luciferase reporter assay was performed to determine the relationship between miR-148b-3p and Delta-like ligand 4(DDL4) or neurogenic locus notch homolog protein 1 (Notch1). OGD/R decreased miR-148b-3p expression in HMC3 cells. After BMSC-Exo treatment, miR-148b-3p expression was upregulated, cell viability and migration were inhibited, cell cycles remained in the G0/G1 phase, and proinflammatory cytokines were decreased in OGD/R-induced HMC3 cells. More importantly, BMSC-Exo miR-148b-3p could further strengthen BMSC-Exo effects. DDL4 and Notch1 are direct targets of miR-148b-3p, respectively. Moreover, the knockdown of DLL4 or Notch1 could inhibit OGD/R-induced HMC3 cell activation. BMSC-Exo miR-148b-3p inhibited OGD/R-induced HMC3 cell activation via inhibiting DLL4 and Notch1 expression, which provided a new strategy for treating cerebral ischemia. • BMSCs-derived exosomes inhibit OGD/R-induced HMC3 cell activation. • BMSCs-derived exosomal miR-148b-3p inhibits OGD/R-induced HMC3 cell activation. • DLL4 and Notch1 are direct targets of miR-148b-3p. • Knockdown of DLL4 or Notch1 inhibits OGD/R-induced HMC3 cell activation. • BMSC-derived exosomal miR-148b-3p inhibits OGD/R-induced HMC3 cell activation via inhibiting DLL4 and Notch1 expression. [ABSTRACT FROM AUTHOR]

BACKGROUND: Medical hydrogels are new functional polymer materials with three-dimensional structural networks and excellent biocompatibility, which have been widely studied in the field of tissue engineering and drug carriers, but the research on the combination of medical hydrogels and Chinese medicine for the treatment of diseases based on tissue engineering is still in the early exploration stage. Therefore, through the analysis of the mechanism of the role of medical hydrogels, the integration of medical hydrogels and Chinese medicine in the research of the joint application of the article, can better provide ideas for scientific researchers, and the joint application of Chinese medicine and medical hydrogels is of great significance. OBJECTIVE: To explore the strategy and significance of Chinese medicine combined with medical hydrogel for disease treatment based on tissue engineering research. METHODS: PubMed and CNKI were used to retrieve articles about the application of Chinese medicine combined with medical hydrogel in tissue engineering from January 2010 to November 2022, with the Chinese and English search terms “hydrogel, traditional Chinese medicine, drug carrier, tissue engineering”. After the initial screening of all articles according to the inclusion and exclusion criteria, the 61 articles with high relevance were retained for review. RESULTS AND CONCLUSION: (1) Although the application of Chinese medicine combined with medical hydrogel is involved in intra-articular, intra-tissue organ, soft tissue wounds, tissue engineering, etc., except for the clinical application of Chinese medicine combined with hydrogel dressing for soft tissue injury, other aspects are still in the experimental stage. (2) The development of Chinese medicine combined with medical hydrogel has great potential and development prospects, but there is a certain difficulty in the manufacture of the gel with high-performance requirements, and it is difficult to master the physical and chemical properties precisely. (3) At present, the comprehensive view of injectable hydrogel with the characteristics of easy to use, its joint use of Chinese medicine can be extended to a wider range, can be used for joint, organ, tissue engineering-related disease treatment. Smart hydrogel has high sensitivity and reversible transformation can also meet the use of the special environment. During the combined use of Chinese medicine, it also needs to understand the mechanism of action of Chinese medicine components. (4) The strategy of combining Chinese medicine with medical hydrogels for disease treatment should start with matching the therapeutic effects of Chinese medicine on organs, tissues and cells combined with appropriate types of medical hydrogels to make up for the shortcomings of traditional Chinese medicine delivery methods and frequent drug delivery. In tissue engineering, hydrogels can be loaded with stem cells after Chinese medicine intervention, or with both Chinese medicine and stem cells for disease treatment. (5) In future research of combined Chinese medicine and medical hydrogel application, we also need to consider: we should ensure that the biological properties of medical hydrogel can be quantified, and grasp the characteristics of hydrogel with different manufacturing processes of different materials to produce the required medical hydrogel that meets the application conditions. In Chinese medicine, we need to comprehensively understand and analyze the therapeutic effects and application mechanisms of known Chinese medicine monomer and Chinese medicine compound extracts, so as to achieve a more perfect combination between Chinese medicine and medical hydrogel under a more clear mechanism. With the continuous improvement of medical science and technology innovation, the medical hydrogel can be innovatively combined with other traditional treatment methods of Chinese medicine, such as acupuncture, massage, cupping and so on, to be used from multiple angles. BACKGROUND: Medical hydrogels are new functional polymer materials with three-dimensional structural networks and excellent biocompatibility, which have been widely studied in the field of tissue engineering and drug carriers, but the research on the combination of medical hydrogels and Chinese medicine for the treatment of diseases based on tissue engineering is still in the early exploration stage. Therefore, through the analysis of the mechanism of the role of medical hydrogels, the integration of medical hydrogels and Chinese medicine in the research of the joint application of the article, can better provide ideas for scientific researchers, and the joint application of Chinese medicine and medical hydrogels is of great significance. OBJECTIVE: To explore the strategy and significance of Chinese medicine combined with medical hydrogel for disease treatment based on tissue engineering research. METHODS: PubMed and CNKI were used to retrieve articles about the application of Chinese medicine combined with medical hydrogel in tissue engineering from January 2010 to November 2022, with the Chinese and English search terms “hydrogel, traditional Chinese medicine, drug carrier, tissue engineering”. After the initial screening of all articles according to the inclusion and exclusion criteria, the 61 articles with high relevance were retained for review. RESULTS AND CONCLUSION: (1) Although the application of Chinese medicine combined with medical hydrogel is involved in intra-articular, intra-tissue organ, soft tissue wounds, tissue engineering, etc., except for the clinical application of Chinese medicine combined with hydrogel dressing for soft tissue injury, other aspects are still in the experimental stage. (2) The development of Chinese medicine combined with medical hydrogel has great potential and development prospects, but there is a certain difficulty in the manufacture of the gel with high-performance requirements, and it is difficult to master the physical and chemical properties precisely. (3) At present, the comprehensive view of injectable hydrogel with the characteristics of easy to use, its joint use of Chinese medicine can be extended to a wider range, can be used for joint, organ, tissue engineering-related disease treatment. Smart hydrogel has high sensitivity and reversible transformation can also meet the use of the special environment. During the combined use of Chinese medicine, it also needs to understand the mechanism of action of Chinese medicine components. (4) The strategy of combining Chinese medicine with medical hydrogels for disease treatment should start with matching the therapeutic effects of Chinese medicine on organs, tissues and cells combined with appropriate types of medical hydrogels to make up for the shortcomings of traditional Chinese medicine delivery methods and frequent drug delivery. In tissue engineering, hydrogels can be loaded with stem cells after Chinese medicine intervention, or with both Chinese medicine and stem cells for disease treatment. (5) In future research of combined Chinese medicine and medical hydrogel application, we also need to consider: we should ensure that the biological properties of medical hydrogel can be quantified, and grasp the characteristics of hydrogel with different manufacturing processes of different materials to produce the required medical hydrogel that meets the application conditions. In Chinese medicine, we need to comprehensively understand and analyze the therapeutic effects and application mechanisms of known Chinese medicine monomer and Chinese medicine compound extracts, so as to achieve a more perfect combination between Chinese medicine and medical hydrogel under a more clear mechanism. With the continuous improvement of medical science and technology innovation, the medical hydrogel can be innovatively combined with other traditional treatment methods of Chinese medicine, such as acupuncture, massage, cupping and so on, to be used from multiple angles. [ABSTRACT FROM AUTHOR]

BACKGROUND: Our previous experimental results have shown that hyaluronic acid hydrogel can act as a vehicle for bone marrow mesenchymal stem cell delivery to improve the cardiac function of rats with myocardial infarction. OBJECTIVE: To explore the molecular mechanism of bone marrow mesenchymal stem cells and hyaluronic acid hydrogel in promoting damaged heart repair. METHODS: Bone marrow mesenchymal stem cells from male Sprague-Dawley rats were isolated and cultured, and then hyaluronic acid-encapsulated bone marrow mesenchymal stem cells were cultured in vitro in a three-dimensional manner. A model of myocardial infarction was made by ligating the left anterior descending artery of female Sprague-Dawley rats. After 1 week, the model rats were screened by ultrasonic testing and then eligible ones were randomly divided into four groups: PBS group (n=12), hyaluronic acid group (n=12), bone marrow mesenchymal stem cell group (n=15), and hyaluronic acid-encapsulated bone marrow mesenchymal stem cell group (n=15). At 1 week after ligation, the model rats underwent the secondary thoracotomy followed by corresponding injections into the infarcted region and its marginal zone. The expression levels of matrix metalloproteinase-2, vascular endothelial growth factor, thymosin β4 and c-Kit were examined at post-injection day 1, week 1 and week 2 by western blot assay. At post-injection week 2, immunofluorescence staining was used to detect the differentiation of transplanted cells. RESULTS AND CONCLUSION: (1) The expression levels of matrix metalloproteinase-2 and vascular endothelial growth factor protein in the infarct zone in the bone marrow mesenchymal stem cell group were significantly up-regulated at week 1 compared with the other three groups (P < 0.05). At week 2, the hyaluronic acid group had a lower expression of matrix metalloproteinase-2 and vascular endothelial growth factor protein than the other three groups (P < 0.05). However, the expression of matrix metalloproteinase-2 and vascular endothelial growth factor protein in the hyaluronic acid+bone marrow mesenchymal stem cell group was not significantly different compared with the bone marrow mesenchymal stem cell group. This was primarily attributable to a prolonged paracrine effect via the controlled release of the hyaluronic acid hydrogel. This prolonged paracrine effect offsets the inhibitory effect induced by hyaluronic acid hydrogel at 2 weeks. (2) Compared with the PBS group, thymosin β4 and c-Kit expression levels in the hyaluronic acid group, bone marrow mesenchymal stem cell group and bone marrow mesenchymal stem cell+hyaluronic acid group were significantly increased (P < 0.05). (3) No differentiation of transplanted cells into cardiomyocytes or blood vessels was detected 2 weeks after transplantation. (4) It is indicated that transplanted bone marrow mesenchymal stem cells promote myocardial repair through the paracrine effect, and hyaluronic acid hydrogel prolongs the paracrine effect of transplanted bone marrow mesenchymal stem cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) can release a large number of exosomes (Exos). The effect of Exos derived from BMSCs on hepatocyte apoptosis and the specific mechanism has not been fully clarified. OBJECTIVE: To explore the effect of miR-21-5p carried by Exos derived from BMSCs on apoptosis of rat liver cells and its mechanism. METHODS: Rat BMSCs were isolated and miR-21-5p NC or miR-21-5p inhibitor was transfected into BMSCs. The Exos were extracted by ultracentrifugation and named (BMSCs+miR-21-5p NC)-Exos and (BMSCs+miR-21-5p inhibitor)-Exos. BMSCs-derived Exos were co-cultured with rat hepatocytes to observe the effect of inhibiting miR-21-5p expression on the apoptosis of rat hepatocytes. The targeting relationship between miR-21-5p and PIK3R1 was verified by double luciferase reporter gene detection. TUNEL was used to detect the effect of miR-21-5p directly targeting PIK3R1 in Exos to activate the PI3K/AKT signaling pathway on hepatocyte apoptosis in BRL rats. RESULTS AND CONCLUSION: (1) The double luciferase reporting system confirmed that when PI3KR1 wild type vector and miR-21-5p mimics co-transfected 293T cells, the luciferase activity decreased significantly compared with the PI3KR1 mutant vector co-transfected group, indicating that miR-21-5p could target PIK3R1. (2) TUNEL test results showed that compared with (BMSCs+miR-21-5p NC)-Exos group, (BMSCs+miR-21-5p inhibitor)-Exos treatment significantly increased the apoptosis rate. Compared with the (BMSCs+miR-21-5p NC)-Exos group, after the addition of AKT inhibitor LY294002, the apoptosis rate was significantly increased. (3) The results indicate that Exos may inhibit the apoptosis of BRL rat hepatocytes through miR-21-5p, in which miR-21-5p directly targets PIK3R1 to activate PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

BACKGROUND: Irisin, a myokine isolated from the transmembrane protein FNDC5 by muscle cells during exercise, has the function of inducing the browning of white adipose tissue, but its effect on lipotoxicity-induced osteogenic differentiation and the mechanism is unclear. OBJECTIVE: To investigate the effect of irisin on the osteogenic ability of palmitic acid-induced bone marrow mesenchymal stem cells and the mechanism of action. METHODS: CCK-8 assay was used to detect the effect of different concentrations of palmitic acid on the proliferation of mouse bone marrow mesenchymal stem cells and the effect of irisin on the proliferation of mouse bone marrow mesenchymal stem cells in the presence of palmitic acid. After pretreatment with irisin and palmitic acid for 24 hours, osteogenic differentiation of mouse bone marrow mesenchymal stem cells was induced by alkaline phosphatase staining as well as qRT-PCR was performed to detect the expression of osteogenesis-related genes on day 7 of osteogenic induction culture. The expression of proteins related to the AMPK/BMP2/SMAD signaling pathway was detected by western blot assay. Alizarin red staining was conducted on day 21 to detect osteogenic differences. RESULTS AND CONCLUSION: (1) The CCK-8 assay results suggested that the amplification of bone marrow mesenchymal stem cells was inversely proportional to the concentration of palmitic acid, but at 0.02 mmol/L concentration, palmitic acid had no significant effect on the amplification of bone marrow mesenchymal stem cells, and irisin did not affect the proliferation of bone marrow mesenchymal stem cells when its mass concentration was in the range of 0.1-20 μg/L. (2) Alkaline phosphatase staining and alizarin red staining showed that palmitic acid inhibited the osteogenic differentiation ability of bone marrow mesenchymal stem cells. Irisin improved palmitic acid-induced osteogenic inhibition of bone marrow mesenchymal stem cells. qRT-PCR results showed that palmitic acid could cause the downregulation of osteogenic-related genes, and irisin could inhibit this trend. (3) Western blot assay results showed that compared with the palmitic acid intervention group, irisin treatment enhanced AMPK/BMP2/SMAD signal transduction in bone marrow mesenchymal stem cells. It is found that irisin can improve the osteogenic differentiation ability of bone marrow mesenchymal stem cells pretreated with palmitic acid, and proposed that the specific mechanism might be mediated by AMPK/BMP/SMAD signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis is a chronic disease mainly involving the damage of articular cartilage and the whole articular tissue, which is the main cause of disability in the elderly. To explore more effective treatment measures, this study analyzed the regulatory role and molecular mechanism of lncRNA LINC00665 (LINC00665) in the chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), providing a valuable theoretical basis for the pathogenesis and patient treatment of osteoarthritis. Methods: Osteoarthritis tissues and healthy tissues were obtained from 52 patients with osteoarthritis and 34 amputated patients without osteoarthritis, and the levels of LINC00665 and miR-214-3p were assessed by RT-qPCR. BMSCs were cultured and induced chondrogenic differentiation. The proliferation ability of BMSCs was detected by CCK-8 method, and the apoptosis level of BMSCs was evaluated by flow cytometry. The content of proteoglycan-glycosaminoglycan (GAG) in cartilage matrix was determined by Alcian blue staining. In addition, the binding relationship between LINC00665 and miR-214-3p was verified by luciferase reporter assay, and the molecular mechanism was further analyzed. Results: In osteoarthritis tissues, LINC00665 was elevated and miR-214-3p was down-regulated. With the chondrogenic differentiation of BMSCs, the level of GAG increased, and LINC00665 expression gradually decreased, while miR-214-3p level was on the contrary. After transfection of pcDNA3.1-LINC00665 in BMSCs, cell proliferation capacity was decreased, apoptosis rate was increased, and GAG content was reduced. Moreover, LINC00665 sponged miR-214-3p and negatively regulate its expression. Transfection of pcDNA3.1-LINC00665-miR-214-3p mimic changed the regulation of pcDNA3.1-LINC00665 on the viability and chondrogenic differentiation of BMSCs. Conclusions: Overexpression of lncRNA LINC00665 inhibited the proliferation and chondrogenic differentiation of BMSCs by targeting miR-214-3p. The LINC00665/miR-214-3p axis may improve joint damage and alleviate the progression of osteoarthritis. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the in-depth research and rapid development of tissue engineering, tissue-engineered scaffolds provide a new opportunity for bone tissue repair. OBJECTIVE: To explore the cell proliferation of bone marrow mesenchymal stem cells after co-culture with the magnesium-based alloy scaffolds, to provide a new idea for the construction of tissue-engineered bone scaffolds and provide a basis for the clinical application of tissue-engineered scaffolds. METHODS: The bone marrow fluid of rabbits was extracted under sterile conditions. Bone marrow mesenchymal stem cells were cultured and isolated by the whole bone marrow adherent method. Bone marrow mesenchymal stem cells were identified by flow cytometry and osteogenic differentiation ability was tested. Bone marrow mesenchymal stem cells at passage 3 were seeded on magnesium-based alloy scaffolds and chitosan polycaprolactone tricalcium phosphate scaffolds respectively. The cell growth was observed by laser confocal scanning on days 3 and 10, and cell proliferation was detected using an MTT assay on days 1, 4, 7, 10 and 14, respectively. RESULTS AND CONCLUSION: (1) The cultured cells highly expressed CD44 and CD90, but hardly CD34. (2) The morphology gradually changed to polygonal after osteogenesis induction. Von Kossa staining showed that the calcium nodules between the cells were stained black, and the alkaline phosphatase activity was significantly higher than that of the control group (P < 0.05). (3) After co-culture of magnesium-based alloy and bone marrow mesenchymal stem cells, confocal scanning showed that the cells could adhere to the scaffold and grow in clusters. With the extension of time, the magnesium-based alloy scaffold was more active in proliferation than the seed cells loaded on the chitosan polycaprolactone tricalcium phosphate scaffold, and the number of cells was significantly increased. MTT assay showed that when the two materials were co-cultured with bone marrow mesenchymal stem cells for 10 days, the cell growth reached its peak. (4) These results indicate that rabbit-derived bone marrow mesenchymal stem cells have a good osteogenic potential. After co-cultured with magnesium based alloy scaffolds, the cells adhered and grew well on the surface of the scaffolds, indicating that the tissue-engineered magnesium-based implants were successfully constructed. [ABSTRACT FROM AUTHOR]