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Background: Low-intensity pulsed ultrasound (LIPUS) has been used as an effective noninvasive method for treating fractures and osteoarthrosis, but the application in the field of oral implantation is in its infancy. This study aimed to clarify the effect and mechanism of LIPUS on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and implant osseointegration, and to provide an experimental basis for future clinical applications. Methods: Dental implants were inserted into Wistar rat femurs, and LIPUS was performed for 4 weeks. Micro-CT and toluidine blue staining were used to assess implant osseointegration. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to identify enriched functional terms and signalling pathways for differentially expressed genes from LIPUS-treated rat BMSC RNAseq data obtained from the GEO database. The random forest method was used to identify key risk genes according to the mean decrease Gini (MDG) coefficient. Then, LIPUS was applied to treat rat BMSCs, and alkaline phosphatase (ALP) staining, alizarin red staining, RT-PCR and western blotting were used to determine whether LIPUS could promote BMSC osteogenic differentiation via integrin α11 (ITGA11) and the focal adhesion pathway. Results: Our in vivo experimentations verified that LIPUS significantly increased new bone formation and osseointegration around the implant in rats. Bioinformatics analysis of RNA-seq data revealed that the upregulated genes in BMSCs after LIPUS treatment were significantly enriched in osteoblast differentiation-related functions and focal adhesion-related pathways. Random forest analysis revealed that ITGA11 was the most significant factor affecting BMSC osteogenic differentiation among the differentially expressed genes. In addition, LIPUS significantly increased ALP expression and mineralized nodule formation in rat BMSCs by upregulating ITGA11 and increasing the activity of FAK/PI3K/AKT/GSK3β/β-catenin pathway. Conclusions: LIPUS can effectively promote implant osseointegration in rats and improve rat BMSC osteogenic differentiation by upregulating ITGA11 and increasing the activity of the downstream focal adhesion pathway. [ABSTRACT FROM AUTHOR]

Background: While autophagy is essential for stem cells' self-renewal and differentiation, its effect on bone marrow mesenchymal stem cells (BMSCs) remains unclear. This study aimed to investigate the interaction between autophagy and osteogenic differentiation using rapamycin (RAPA), a classical autophagy agonist with osteo-regulatory effects. Methods: Rat BMSC's autophagy was analyzed after osteoinduction (0, 7, 14, and 21 d) by western blotting, immunofluorescence, and real-time quantitative polymerase chain reaction (RT-qPCR). In addition, we evaluated osteogenic differentiation using alizarin red staining, alkaline phosphatase assays, and RT-qPCR/Western blotting quantification of bone sialoprotein, type 1 collagen, alkaline phosphatase, osteopontin, and Runt-related transcription factor 2 mRNA and protein levels. Results: The BMSC's basal autophagy level gradually decreased during osteogenic differentiation with a decrease in BECN1 level and the lipidated (LC3-II) to unlipidated (LC3-I) microtubule-associated protein 1 light chain 3 ratio and an increase in the expression of selective autophagic target p62. In contrast, it increased with increasing RAPA concentration. Furthermore, while 2 nM RAPA promoted BMSC osteogenic differentiation on days 7 and 14, 5 nM RAPA inhibited osteogenesis on days 14 and 21. Inhibition of autophagy by the inhibitor 3-methyladenine could impair RAPA's osteogenesis-enhancing effect on BMSCs. Conclusions: The BMSC's basal autophagy level decreased over time during osteogenic differentiation. However, an appropriate RAPA concentration promoted BMSC osteogenic differentiation via autophagy activation. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Noncoding RNAs were discovered to control a variety of developmental mechanisms, including osteogenesis. According to emerging evidence, cryptochrome circadian-regulating (CRY) proteins have emerged as essential controllers of osteoblast differentiation. The linked processes, on the other hand, are still unknown. The specific process that underpins osteoblast differentiation and proliferation is yet unknown. This research gives a meta-analysis of CRY2's impact on mouse osteoblast differentiation via the control of the WNT/β–catenin signaling pathways. Western blot and quantitative real-time PCR were used to identify Cry2 expression levels, components in the osteoblast-associated signaling pathway, and osteoblast transcription markers. The osteogenic condition was measured utilizing alkaline phosphatase (ALP) and alizarin red (AR) staining, whereas cell growth rates were measured using CCK8 assays. An ectopic bone formation experiment was used to determine the osteogenic potential of osteoblasts. Cry2 stimulates the osteogenic development of mouse osteoblasts through canonical Wnt/β-catenin signaling, according to the findings. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fructus Sophorae (FS), the dry mature fruit of Sophora japonica Leguminosae, is a valuable traditional Chinese medicine resource with flavonoids as the major active ingredients. To identify the plant-derived estrogenlike flavonoids serving as potential osteoporosis chemopreventive agents, we isolated and identified 27 flavonoids compounds, including 17 compounds obtained for the first time from FS. To screen out the flavonoids with estrogen-like biological behavior from the 11 high yield compounds, we set up an in vitro screening system in rat osteoblast MC3T3-E1 cells including MTT assay, alkaline phosphatase staining and Alizarin red S staining assay to examine the effects on cell proliferation, differentiation and mineralization of osteoblast cells respectively. Six flavonoids, including genistein, sophoricoside, sophorabioside, sophoraflavonoloside, nicotiflorin and rutin, significantly increased the cellular activity of MC3T3-E1 cells. Furthermore, blocking the estrogen receptor signaling by tamoxifen compromised the effects above significantly, suggesting the 6 compounds behave as estrogen-like reagents. Moreover, the interaction between the six flavonoids from FS and estrogen receptor was clarified by molecular docking method from Glide XP. Collectively, being used as food and medicine in China, FS is rich in flavonoids with estrogen-like effects, may be used as healthy supplementary in treating postmenopausal women osteoporosis. [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: Panax notoginseng saponins (PNS) is the main effective component of Panax notoginseng, have various pharmacologic activities such as antioxidant, anti-inflammatory, and estrogen-like bioactivities, have been shown to be an effective agent on anti-osteoporosis. Bone marrow stromal cells (BMSCs) play a crucial homeostatic role in skeletal modeling and remodeling due to their capability to differentiate into osteooblasts. Whether PNS has effect on osteogenic differentiation of BMSCs are unknown. This study was designed to investigate the effects of PNS on the proliferation and osteogenic differentiation of BMSCs in vitro. Materials and methods: When BMSCs cultivated in the basal medium or the osteogenic induction medium (OS with or without PNS), cell proliferation was analyzed using an MTT assay, the mineralization was assessed using Alizarin red S staining, the alkaline phosphatase activity was measured using a commercial kit, the mRNA level of osteogenic gene and PPARγ2 gene were determined using RT-PCR, the protein level of PPARγ2 was analyzed by Western blotting. Results: BMSCs cultured in the basal medium with PNS caused a significant increase in proliferation. PNS treatment increased ALP activity, Alizarin red S staining and mRNA level of ALP, Cbfa 1, OC, and BSP, whereas decreased the mRNA level and protein expression of PPARγ2 during osteogenic induction. In addition, the effects of PNS treatment were dose-dependent relationship. Conclusion: PNS could stimulate BMSCs proliferation and promote their osteogenic differentiation by up-regulation expression of osteogenic marker gene and down-regulation expression of adipogenic marker gene in a dose-dependent manner. Thus, PNS may play an important therapeutic role in osteoporosis patients by improving osteogenic differentiation of BMSCs. [Copyright &y& Elsevier]

Er-xian Decoction (EXD) is a well-known prescription widely used to prevent and treat climacteric syndrome and osteoporosis in China. BK channel positively affects osteoblast bone formation in vitro. However, it is still unclear whether the effect of EXD on promoting osteoblasts osteogenic differentiation is related to BK channel. The study is aimed at determining whether the EXD-containing serum promotes the proliferation of osteoblasts and their differentiation through BK channel. The chemical compounds of EXD were analyzed by UPLC-Q-TOF/MS. An osteogenic induction medium (OM) was used to induce MC3T3-E1 cells' osteogenic differentiation. The effects of EXD-containing serum and tetraethylammonium (TEA) on the proliferation activity of Mc3t3-e1 cells were detected by CCK-8 assay. ALP activity was determined by an alkaline phosphatase kit. The protein expression (BMP2, OPG, and COL1) was analyzed by Western blot, and the mRNA expression (Runx2, OPG, and BMP2) was assessed by real-time PCR. Alizarin red was used to stain the mineralized region of osteoblasts. In addition, we analyzed the relationship between BK channel and its downstream PTEN/Akt/Foxo1 signaling pathway. 72 compounds were identified by UPLC-Q-TOF/MS analysis in EXD. Mangiferin, ferulic acid, berberine, and icariin were main active components of EXD. EXD-containing serum could enhance the cell viability of MC3T3-E1 cells by decreasing the expression of BKα protein. EXD-containing serum increased ALP activity and calcium nodule formation of Mc3t3-e1 cells, promoted the protein expression of BKα, COL1, BMP2, OPG, and the mRNA expression of RUNX2, OPG, and BMP2, however, these effects can be reversed after adding TEA. In addition, EXD-containing serum could upregulate phosphorylation of Akt and Foxo1 in osteogenic-induced Mc3t3-e1 cells, and lower the expression of PTEN. And these effects of EXD-containing serum could be reduced by TEA. The effect of EXD-containing serum on promoting cell proliferation and osteogenic differentiation of Mc3t3-e1 cells might be linked to the regulation of BK channel. [Display omitted] • 72 chemical components were identified in EXD by UPLC-Q-TOF/MS. • EXD-containing serum promotes Mc3t3-e1 cell proliferation by inhibiting BKα expression. • EXD-containing serum promotes osteoblasts osteogenic differentiation by increasing BKα expression. • EXD-containing serum activates PTEN/Akt/Foxo1 signaling pathway through BK channel to accelerate bone formation. [ABSTRACT FROM AUTHOR]

Calciphylaxis is a rare but potentially fatal disease commonly occurred in dialysis patients. Despite some previous studies on risk factors for calciphylaxis, there is still a lack of data from Chinese population. The retrospective matched case–control study about calciphylaxis was performed in Zhongda Hospital affiliated to Southeast University. The case group involved 20 hemodialysis patients who were newly diagnosed with calciphylaxis from October 2017 to December 2018. The 40 noncalciphylaxis patients undergoing dialysis with the same age and duration of dialysis were randomly selected as controls. Most of calciphylaxis patients were male and elderly, while overweight people were more susceptible to the disease. Although incidence of secondary hyperparathyroidism was higher in calciphylaxis patients, the differences in duration of elevated serum intact parathyroid hormone (iPTH) and its highest value did not reach statistical significance compared with controls. No significant difference in warfarin therapy was discernible between two groups. The univariate regression analysis indicated that male, score of use of activated vitamin D and its analogues, corrected serum calcium level, serum phosphate, Ca × P product, iPTH, albumin, and alkaline phosphatase (ALP) level were significantly associated with calciphylaxis. Elevated levels of serum phosphate (OR 4.584, p = 0.027) and ALP (OR 1.179, p = 0.036), decreased level of serum albumin (OR 1.330, p = 0.013) were independent risk factors after multivariate analysis. This is the first report of risk factors associated with calciphylaxis in China. Increased levels of serum phosphate and ALP, decreased level of serum albumin were vital high-risk factors for calciphylaxis in Chinese hemodialysis population. [ABSTRACT FROM AUTHOR]