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Herein, we report that the phosphorous-doped 1 T-MoS2 as co-catalyst decorated nitrogen-doped g-C3N4 nanosheets (P-1 T-MoS2@N-g-C3N4) are prepared by the hydrothermal and annealing process. The obtained P-1 T-MoS2@N-g-C3N4 composite presents an enhanced photocatalytic N2 reduction rate of 689.76 μmol L-1 g-1h−1 in deionized water without sacrificial agent under simulated sunlight irradiation, which is higher than that of pure g-C3N4 (265.62 μmol L-1 g-1h−1), 1 T-MoS2@g-C3N4 (415.57 μmol L-1 g-1h−1), 1 T-MoS2@N doped g-C3N4 (469.84 μmol L-1 g-1h−1), and P doped 1 T-MoS2@g-C3N4 (531.24 μmol L-1 g-1h−1). In addition, compared with pure g-C3N4 NSs (2.64 mmol L-1 g-1h−1), 1 T-MoS2@g-C3N4 (4.98 mmol L-1 g-1h−1), 1 T-MoS2@N doped g-C3N4 (6.21 mmol L-1 g-1h−1), and P doped 1 T-MoS2@g-C3N4 (9.78 mmol L-1 g-1h−1), P-1 T-MoS2@N-g-C3N4 (11.12 mmol L-1 g-1h−1) composite also shows a significant improvement for photocatalytic N2 fixation efficiency in the sacrificial agent (methanol). The improved photocatalytic activity of P-1 T-MoS2@N-g-C3N4 composite is ascribed to the following advantages: 1) Compared to pure g-C3N4, P-1 T-MoS2@N-g-C3N4 composite shows higher light absorption capacity, which can improve the utilization rate of the catalyst to light; 2) The P doping intercalation strategy can promote the conversion of 1 T phase MoS2, which in turn in favor of photogenerated electron transfer and reduce the recombination rate of carriers; 3) A large number of active sites on the edge of 1 T-MoS2 and the existence of N doping in g-C3N4 contribute to photocatalytic N2 fixation.

Cardiovascular safety assessment is vital for drug development, yet human cardiovascular cell models are lacking. In vitro mass-generated human pluripotent stem cell (hPSC)-derived cardiovascular cells are a suitable cell model for preclinical cardiovascular safety evaluations. In this study, we established a preclinical toxicology model using same-origin hPSC-differentiated cardiomyocytes (hPSC-CMs) and endothelial cells (hPSC-ECs). For validation of this cell model, alirocumab, a human antibody against proprotein convertase subtilisin kexin type 9 (PCSK9), was selected as an emerging safe lipid-lowering drug; atorvastatin, a common statin (the most effective type of lipid-lowering drug), was used as a drug with reported side effects at high concentrations, while doxorubicin was chosen as a positive cardiotoxic drug. The cytotoxicity of these drugs was assessed using CCK8, ATP, and lactate dehydrogenase release assays at 24, 48, and 72 h. The influences of these drugs on cardiomyocyte electrophysiology were detected using the patch-clamp technique, while their effects on endothelial function were determined by tube formation and Dil-acetylated low-density lipoprotein (Dil-Ac-LDL) uptake assays. We showed that alirocumab did not affect the cell viability or cardiomyocyte electrophysiology in agreement with the clinical results. Atorvastatin (5–50 μM) dose-dependently decreased cardiovascular cell viability over time, and at a high concentration (50 μM, ~100 times the normal peak serum concentration in clinic), it affected the action potentials of hPSC-CMs and damaged tube formation and Dil-Ac-LDL uptake of hPSC-ECs. The results demonstrate that the established same-origin hPSC-derived cardiovascular cell model can be used to evaluate lipid-lowering drug safety in cardiovascular cells and allow highly accurate preclinical assessment of potential drugs.

Myocardial infarction (MI) results in cardiomyocyte death and ultimately leads to heart failure. Pyroptosis is a type of the inflammatory programmed cell death that has been found in various diseased tissues. However, the role of pyroptosis in MI heart remains unknown. Here, we showed that CXADR‐like membrane protein (CLMP) was involved in pyroptosis in the mouse MI heart. Our data showed that CLMP was strongly expressed in fibroblasts of the infarcted mouse hearts. The Clmp +/− mice showed more serious myocardial fibrosis and ventricular dysfunction post‐MI than wild‐type (Clmp +/+) mice, indicating a protective effect of the fibroblast‐expressed CLMP against MI‐induced heart damage. Transcriptome analyses by RNA sequencing indicated that Il‐1β mRNA was significantly increased in the MI heart of Clmp +/− mouse, which indicated a more serious inflammatory response. Meanwhile, cleaved caspase‐1 and Gasdermin D were significantly increased in the Clmp +/− MI heart, which demonstrated enhanced pyroptosis in the Clmp knockdown heart. Further analysis revealed that the pyroptosis mainly occurred in cardiac fibroblasts (CFs). Compared to wild‐type fibroblasts, Clmp +/− CFs showed more serious pyroptosis and inflammatory after LPS plus nigericin treatment. Collectively, our results indicate that CLMP participates in the pyroptotic and inflammatory response of CFs in MI heart. We have provided a novel pyroptotic insight into the ischaemic heart, which might hold substantial potential for the treatment of MI.

Background Endothelial cells are located in the inner lumen of blood and lymphatic vessels and exhibit the capacity to form new vessel branches from existing vessels through a process called angiogenesis. This process is energy intensive and tightly regulated. Glycolysis is the main energy source for angiogenesis. Retinoic acid (RA) is an active metabolite of vitamin A and exerts biological effects through its receptor retinoic acid receptor (RAR). In the clinic, RA is used to treat acne vulgaris and acute promyelocytic leukemia. Emerging evidence suggests that RA is involved in the formation of the vasculature; however, its effect on endothelial cell angiogenesis and metabolism is unclear. Methods Our study was designed to clarify the abovementioned effect with human embryonic stem cell-derived endothelial cells (hESC-ECs) employed as a cell model. Results We found that RA inhibits angiogenesis, as manifested by decreased proliferation, migration and sprouting activity. RNA sequencing revealed general suppression of glycometabolism in hESC-ECs in response to RA, consistent with the decreased glycolytic activity and glucose uptake. After screening glycometabolism-related genes, we found that fructose-1,6-bisphosphatase 1 (FBP1), a key rate-limiting enzyme in gluconeogenesis, was significantly upregulated after RA treatment. After silencing or pharmacological inhibition of FBP1 in hESC-ECs, the capacity for angiogenesis was enhanced, and the inhibitory effect of RA was reversed. ChIP-PCR demonstrated that FBP1 is a target gene of RAR. When hESC-ECs were treated with the RAR inhibitor BMS493, FBP1 expression was decreased and the effect of RA on angiogenesis was partially blocked. Conclusions The inhibitory role of RA in glycometabolism and angiogenesis is RAR/FBP1 dependent, and FBP1 may be a novel therapeutic target for pathological angiogenesis.

In the past decades, human induced pluripotent stem cells (iPSCs) have been generated by the ectopic expression of "Yamanaka factors" in multiple somatic cells. However, the procedure to get access to donor cells is hard or invasive in most cases. Hereon, we depict a stepwise method developed in our laboratory for the generation of iPSCs from renal epithelial cells present in urine, which is noninvasive, nonintegrating, and universal. The resulting urinary iPSCs (UiPSCs) exhibit pluripotent characteristics resemble embryonic stem cells (ESCs) and thus urine may be a favorable source for generating iPSCs.

Herein, we report that the phosphorous-doped 1 T-MoS

Rationale: As a hallmark of various heart diseases, cardiac fibrosis ultimately leads to end-stage heart failure. Anti-fibrosis is a potential therapeutic strategy for heart failure. Long noncoding RNAs (lncRNAs) have emerged as critical regulators of heart diseases that promise to serve as therapeutic targets. However, few lncRNAs have been directly implicated in cardiac fibrosis. Methods: The lncRNA expression profiles were assessed by microarray in cardiac fibrotic and remote ventricular tissues in mice with myocardial infarction. The mechanisms and functional significance of lncRNA-AK137033 in cardiac fibrosis were further investigated with both in vitro and in vivo models. Results: We identified 389 differentially expressed lncRNAs in cardiac fibrotic and remote ventricular tissues in mice with myocardial infarction. Among them, a lncRNA (AK137033) we named Safe was enriched in the nuclei of fibroblasts, and elevated in both myocardial infarction and TGF-β-induced cardiac fibrosis. Knockdown of Safe prevented TGF-β-induced fibroblast-myofibroblast transition, aberrant cell proliferation and secretion of extracellular matrix proteins in vitro, and mended the impaired cardiac function in mice suffering myocardial infarction. In vitro studies indicated that knockdown of Safe significantly inhibited the expression of its neighboring gene Sfrp2, and vice versa. The Sfrp2 overexpression obviously disturbed the regulatory effects of Safe shRNAs in both the in vitro cultured cardiac fibroblasts and myocardial infarction-induced fibrosis. Dual-Luciferase assay demonstrated that Safe and Sfrp2 mRNA stabilized each other via their complementary binding at the 3'-end. RNA electrophoretic mobility shift assay and RNA immunoprecipitation assay indicated that RNA binding protein HuR could bind to Safe-Sfrp2 RNA duplex, whereas the knockdown of HuR dramatically reduced the stabilization of Safe and Sfrp2 mRNAs, down-regulated their expression in cardiac fibroblasts, and thus inhibited TGF-β-induced fibrosis. The Safe overexpression partially restrained the phenotype change of cardiac fibroblasts induced by Sfrp2 shRNAs, but not that induced by HuR shRNAs. Conclusions: Our study identifies Safe as a critical regulator of cardiac fibrosis, and demonstrates Safe-Sfrp2-HuR complex-mediated Sfrp2 mRNA stability is the underlying mechanism of Safe-regulated cardiac fibrosis. Fibroblast-enriched Safe could represent a novel target for anti-fibrotic therapy in heart diseases.

Ephrin B2 (EFNB2) is the first identified and most widely used marker for arterial endothelial cells (AECs). We generated a heterozygous EFNB2-2A-mCherry reporter H1 cell line, H1-EFNB2-2A-mCherry+/- (WAe001-A-57), by CRISPR/Cas9-mediated insertion of 2A-mCherry cassette into the EFNB2 gene locus, immediately before the translation stop codon. The H1-EFNB2-2A-mCherry reporter cells were pluripotent and could differentiate into all three germ layer lineages. Simultaneous expression of mCherry was observed when expression of EFNB2 was increased during endothelial cell differentiation. Thus, the generated reporter cells enable live identification of EFNB2-positive AECs, and screening of small molecule compound and target genes that promote AEC differentiation.

In the past decades, human induced pluripotent stem cells (iPSCs) have been generated by the ectopic expression of "Yamanaka factors" in multiple somatic cells. However, the procedure to get access to donor cells is hard or invasive in most cases. Hereon, we depict a stepwise method developed in our laboratory for the generation of iPSCs from renal epithelial cells present in urine, which is noninvasive, nonintegrating, and universal. The resulting urinary iPSCs (UiPSCs) exhibit pluripotent characteristics resemble embryonic stem cells (ESCs) and thus urine may be a favorable source for generating iPSCs.

Cardiomyocytes differentiated from human embryonic stem cells (hESCs) represent a promising cell source for heart repair, disease modeling and drug testing. However, improving the differentiation efficiency and maturation of hESC-derived cardiomyocytes (hESC-CMs) is still a major concern. Retinoic acid (RA) signaling plays multiple roles in heart development, and studies on RA can provide clues for understanding cardiomyocyte differentiation and maturation. In this study, we studied the roles of RA during cardiomyocyte differentiation and maturation, systematically. After adding RA at different stages of cardiomyocyte differentiation, we compared the efficiency of differentiation by quantitative real-time PCR and flow cytometry. We found that RA treatment at the lateral mesoderm stage (days 2-4) significantly improved cardiomyocyte differentiation, as evidenced by the upregulation of TNNT2, NKX2.5 and MYH6 on day 10 of differentiation. In addition, flow cytometry showed that the proportion of differentiated cardiomyocytes in the RA-treated group was significantly higher than that in control group. Furthermore, RA was added at different time intervals after purification to induce cardiomyocyte maturation. Our results demonstrated that RA treatment on days 15-20 increased cardiomyocyte area, sarcomere length, multinucleation and mitochondrial copy number, and promoted RNA splicing switch. Importantly, RA-treated cardiomyocytes showed decreased glycolysis and enhanced mitochondrial oxidative phosphorylation, with the increased utilization of fatty acid and exogenous pyruvate but not glutamine. In conclusion, our data indicated that RA treatment at an early time window (days 2-4) promotes the efficiency of cardiomyocyte differentiation and that RA treatment post beating (days 15-20) promotes cardiomyocyte metabolic maturation. The biphasic effects of RA provide new insights for improving cardiomyocyte differentiation and quality.

Cardiomyocytes differentiated from human embryonic stem cells (hESCs) represent a promising cell source for heart repair, disease modeling and drug testing. However, improving the differentiation efficiency and maturation of hESC-derived cardiomyocytes (hESC-CMs) is still a major concern. Retinoic acid (RA) signaling plays multiple roles in heart development. However, the effects of RA on cardiomyocyte differentiation efficiency and maturation are still unknown. Methods: RA was added at different time intervals to identify the best treatment windows for cardiomyocyte differentiation and maturation. The efficiency of cardiomyocyte differentiation was detected by quantitative real-time PCR and flow cytometry. Cardiomyocytes maturation was detected by immunofluorescence staining, metabolic assays and patch clamp to verify structural, metabolic and electrophysiological maturation, respectively. RNA sequencing was used for splicing analysis. Results: We found that RA treatment at the lateral mesoderm stage (days 2-4) significantly improved cardiomyocyte differentiation, as evidenced by the upregulation of TNNT2, NKX2.5 and MYH6 on day 10 of differentiation. In addition, flow cytometry showed that the proportion of differentiated cardiomyocytes in the RA-treated group was significantly higher than that in control group. RA treatment on days 15-20 increased cardiomyocyte area, sarcomere length, multinucleation and mitochondrial copy number. RNA sequencing revealed RA promoted RNA isoform switch to the maturation-related form. Meanwhile, RA promoted electrophysiological maturation and calcium handling of hESC-CMs. Importantly, RA-treated cardiomyocytes showed decreased glycolysis and enhanced mitochondrial oxidative phosphorylation, with the increased utilization of fatty acid and exogenous pyruvate but not glutamine. Conclusion: Our data indicated that RA treatment at an early time window (days 2-4) promotes the efficiency of cardiomyocyte differentiation and that RA treatment post beating (days 15-20) promotes cardiomyocyte maturation. The biphasic effects of RA provide new insights for improving cardiomyocyte differentiation and quality.

Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) can differentiate into spontaneously beating cardiomyocytes in vitro, and hold great promise for cardiovascular disease modeling, therapy and drug discovery. However, these applications were hampered by low yield and purity of the in vitro differentiated cardiomyocytes. Although miRNAs represent a type of potential candidates to promote cardiac differentiation, most of cardiomyocyte-enriched miRNAs have not been functionally investigated until now. This study investigated the roles of MIR148A family in cardiac differentiation from hESCs. The MIR148A family is composed of MIR148A , MIR148B and MIR152 , three highly conserved miRNAs sharing same seed sequences. The expression levels of all MIR148A family members were progressively increased during cardiac differentiation in vitro. By using CRISPR-Cas9-mediated knockout, we demonstrated that triple knockout of MIR148A family ( MIR148A -TKO), rather than individual knockout of each members, could grossly inhibited TNNT2 + cardiomyocyte generation. Ectopic expression of MIR152 significantly restored the cardiac differentiation efficiency of MIR148A -TKO hESCs. The transcriptome analysis identified a total of 1071 upregulated genes and 766 down-regulated genes in the MIR148A -TKO hESC-derived cells compared to wild-type hESC-derived cells at day 4 of cardiac differentiation. Gene Ontology analysis revealed that most genes down-regulated in MIR148A -TKO hESC-derived cells were involved in the events of lateral/cardiac mesoderm development, while the up-regulated genes were mainly involved in the events of paraxial/somitic development. Furthermore, the NOTCH ligand Delta-like1 ( DLL1 ) was validated as the target gene of MIR148A family, and the knockdown of DLL1 could inhibit target gene expression of Notch signaling pathway, and promote cardiac differentiation of MIR148A -TKO hESCs. Our findings demonstrate a new function of MIR148A family during cardiac differentiation. Synergistic inhibition of DLL1 -mediated Notch signaling represents a major mechanism for the MIR148A family to inhibit undesired lineage formation and promote hESC differentiation into cardiomyocytes.

MicroRNAs (miRNAs), as a class of naturally occurring RNAs, play important roles in cardiac physiology and pathology. There are many miRNAs that show multifarious expression patterns during cardiomyocyte genesis. Here, we focused on the MIR148A family, which is composed of MIR148A, MIR148B and MIR152, and shares the same seed sequences. The expression levels of all MIR148A family members progressively increased during the differentiation of human embryonic stem cells (hESCs) into cardiomyocytes. The deletion of MIR148A family (MIR148A-TKO) resulted in a decreased proportion of cardiomyocytes after cardiac induction, which was restored by the ectopic expression of MIR148A family members. Transcriptome analyses indicated that the MIR148A family could partially repress paraxial mesodermal differentiation from primitive streak cells. In turn, these miRNAs promoted lateral mesoderm and cardiomyocyte differentiation. Furthermore, the NOTCH ligand Delta-like 1 (DLL1) was validated as the target gene of MIR148A family, and knockdown of DLL1 could promote the cardiomyocyte differentiation of MIR148A-TKO hESCs. Thus, our results demonstrate MIR148A family could promote cardiomyocyte differentiation by inhibiting undesired paraxial mesoderm lineage commitment, which improves our understanding on cardiomyocyte differentiation from hESCs.

Background Ischemic heart diseases are still a threat to human health. Human pluripotent stem cell-based transplantation exhibits great promise in cardiovascular disease therapy, including heart ischemia. The purpose of this study was to compare the efficacy of human embryonic stem cell-derived cardiomyocyte (ESC-CM) therapy in two heart ischemia models, namely, permanent ischemia (PI) and myocardial ischemia reperfusion (IR). Methods Human embryonic stem cell-derived cardiomyocytes were differentiated from engineered human embryonic stem cells (ESC-Rep) carrying green fluorescent protein (GFP), herpes simplex virus-1 thymidine kinase (HSVtk), and firefly luciferase (Fluc). Two different heart ischemia models were generated by the ligation of the left anterior descending artery (LAD), and ESC-Rep-derived cardiomyocytes (ESC-Rep-CMs) were transplanted into the mouse hearts. Cardiac function was analyzed to evaluate the outcomes of ESC-Rep-CM transplantation. Bioluminescence signal analysis was performed to assess the cell engraftment. Finally, the inflammation response was analyzed by real-time PCR and ELISA. Results Cardiac function was significantly improved in the PI group with ESC-Rep-CM injection compared to the PBS-injected control, as indicated by increased left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS), as well as reduced fibrotic area. However, minimal improvement by ESC-Rep-CM injection was detected in the IR mouse model. We observed similar engraftment efficiency between PI and IR groups after ESC-Rep-CM injection. However, the restricted inflammation was observed after the injection of ESC-Rep-CMs in the PI group, but not in the IR group. Transplantation of ESC-Rep-CMs can partially preserve the heart function via regulating the inflammation response in the PI model, while little improvement of cardiac function in the IR model may be due to the less dynamic inflammation response by the mild heart damage. Conclusions Our findings identified the anti-inflammatory effect of ESC-CMs as a possible therapeutic mechanism to improve cardiac function in the ischemic heart. Electronic supplementary material The online version of this article (10.1186/s13287-019-1271-4) contains supplementary material, which is available to authorized users.

Figure S1. Generation of reporter-engineered human embryonic stem cells (ESC-Rep). (A) Schematic diagram of CRISPR/Cas9-mediated homologous recombination in AAVS1 locus of PPP1R12C gene. (B) Procedure of ESC-Rep generation. Figure S2. Stage-specific gene expression during cardiomyocyte differentiation. Real-time PCR analysis for markers of pluripotency (POU5F1 and NANOG), mesoderm (T and MIXL1), cardiac mesoderm (MESP1 and EVX1), cardiac progenitors (NKX2.5 and GATA4), and cardiomyocytes (MYH6, MYH7, and TNNI3) during the cardiac differentiation. Figure S3. Characteristics of ESC-Rep-CMs. (A) Flow cytometry assay for troponin T (TNNT2)-positive cardiomyocytes after purification. (B) Patch clamp for electrophysiological characteristics of ESC-Rep-CMs. Figure S4. Postoperative cardiac evaluation in mice. (A) Electrocardiogram analysis of mice in the Sham, PI, and IR groups after surgery. (Bâ D) Heart function analysis of mice in the Sham, PI, and IR groups at day 7 post surgery. All data are presented as the mean Âą SEM; one-way ANOVA; *p < 0.05, **p < 0.01. Table S1. Primers used in this study. Table S2. Antibodies used in this study. Table S3. Cardiac parameters acquired from echocardiography at Day 28. (DOCX 12013 kb)

Rationale: Aging is one of the most significant risk factors for cardiovascular diseases, and the incidence of myocardial ischemia increases dramatically with age. Some studies have reported that cardiosphere-derived cells (CDCs) could benefit the injured heart. Nevertheless, the convincing evidence on CDC-induced improvement of aging heart is still limited. Objective: In this study, we tested whether the CDCs isolated from neonatal mice could benefit cardiac function in aging mice. Methods and Results: We evaluated cardiac function of PBS- (n=15) and CDC-injected (n=19) aging mice. Echocardiography indicated that left ventricular (LV) ejection fraction (57.46%±3.57% versus 57.86%±2.44%) and LV fraction shortening (30.67%±2.41% versus 30.51%±1.78%) showed similar values in PBS- and CDC-injected mice. The diastolic wall thickness of LV was significantly increased after CDC injection, resulting in reduced diastolic LV volume. The pulse-wave Doppler and tissue Doppler imaging indicated that aging mice receiving PBS or CDC injection presented similar values of the peak early transmitral flow velocity, the peak late transmitral flow velocity, the ratio of the peak early transmitral flow velocity to the peak late transmitral flow velocity, and the ratio of the peak early transmitral flow velocity to the peak early diastolic mitral annular velocity, respectively. Pressure-volume loop experiment indicated that the LV end-diastolic pressure-volume relationship and end-systolic pressure-volume relationship were comparable in both PBS- and CDC-injected mice. Postmortem analysis of aging mouse hearts showed similar fibrotic degree in the 2 groups. In addition, the aging markers showed comparable expression levels in both PBS- and CDC-injected mice. The systemic aging performance measures, including exercise capacity, hair regrowth capacity, and inflammation, showed no significant improvement in CDC-injected mice. Finally, the telomere length was comparable between PBS- and CDC-injected mice. Conclusions: Together, these results indicate that CDCs do not improve heart function and systemic performances in aging mice.

Cells encapsulation by biomaterials has been widely studied as a strategy of building tissue construct in tissue engineering. Conventional encapsulation of cells using hydrogels often needs the polymerization process or relatively complex molding process. In this study, we developed a facile strategy for the in situ fabrication of biodegradable cell-laden starch foams. By utilizing the unique gelatinization property of starch, cell-laden starch foams with tunable architecture were rapidly prepared in a green and biological-friendly process. The bubble size and stiffness of starch foams could be tuned by controlling the content of premixed starch in the cell culture medium. Cells were encapsulated in situ during the foaming process, and the resultant starch foams could be used as building blocks to fabricate three-dimensional tissue construct. The potential application of the cell-laden starch foams in neural tissue engineering was also validated. RSC96 Schwann cells were encapsulated in the starch foams and revealed good viability. Due to the serum-induced degradation of the starch, RSC96 Schwann cells could be released from the starch foams in a controlled manner while remaining high viability. Dorsal root ganglion (DRG) neurons co-cultured with the cell-laden starch foams extended significantly longer neurites compared with neurons cultured in minimum Eagle's medium (664.88 ± 190.39 μm vs. 311.19 ± 105.25 μm). DRG neurons retained high viability even after encapsulation in the starch foams for 3 days. This facile strategy of rapidly fabricating cell-laden starch foams can be further extended to construct centimeter-scale micro-tissue for tissue engineering applications. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:104-116, 2020.

Introduction: The injured heart undergoes a major process of cellular apoptosis in the initial stage of MI, therefore, the most fundamental method to prevent post-MI remodeling is to suppress cardiomyocyte apoptosis. In this study, we have illustrated the key role of long noncoding RNA, Maternally expressed gene 3 ( Meg3 ), on cardiomyocyte apoptosis and the underlying mechanisms in heart. Methods: Neonatal murine cardiomyocytes and human ESC-derived cardiomyocytes were subjected to hypoxia, and cellular apoptosis was evaluated with Annexin V assay. The Meg3 regulation by p53 was measured by luciferase reporter assay. The complex of Meg3 and RNA-binding protein FUS (Fused in sarcoma) was determined by EMSA and RIP. Adeno-Associated Virus serotype 9 (AAV9) system was employed to knock down Meg3 in cardiomyocytes in vivo, and the cardiac function was evaluated by echocardiography and ex-vivo assays. Results: We first found that Meg3 was progressively upregulated in the murine injured heart after MI, and it showed the pro-apoptotic functions in primary cardiomyocytes. Meg3 could be directly upregulated by p53 during hypoxia condition, and was involved in apoptotic regulation via its direct binding with FUS. The Meg3 knockdown in cardiomyocytes by AAV9 system could preserve heart function in murine myocardial infarction. Moreover, its pro-apoptotic function was conserved in human cardiomyocytes. Conclusion: Together, these results indicate that p53-induced Meg3 - FUS complex plays an important role on cardiomyocyte apoptosis post-MI, and its specific knockdown in cardiomyocytes with AAV9 system represents a promising method to treat myocardial infarction.

In order to solve the problem of ineffective cooperation across multiple departments and application systems in the spacecraft assembly business, the paper analyzed the transmission demand for design data and process data, proposed an integration framework of spacecraft assembly business system, and solved key issues in the integration process such as data transmission and technical state synchronization between PLM and MES.

Bone morphogenetic protein-2 (BMP-2) is a potent osteoinductive cytokine that plays a critical role in bone regeneration and repair. However, its distribution and side effects are major barriers to its success as therapeutic treatment. The improvement of therapy using collagen delivery matrices has been reported. To investigate a delivery system on posterolateral spinal fusion, both engineered human BMP-2 with a collagen binding domain (CBD-BMP-2) and collagen scaffolds were developed and their combination was implanted into Sprague-Dawley (SD) rats to study Lumbar 4-5 (L4-L5) posterolateral spine fusion. We divided SD rats into three groups, the sham group (G1, n = 20), the collagen scaffold-treated group (G2, n = 20) and the BMP-2-loaded collagen scaffolds group (G3, n = 20). 16 weeks after surgery, the spines of the rats were evaluated by X-radiographs, high-resolution micro-computed tomography (micro-CT), manual palpation and hematoxylin and eosin (H&E) staining. The results showed that spine L4-L5 fusions occurred in G2(40%) and G3(100%) group, while results from the sham group were inconsistent. Moreover, G3 had better results than G2, including higher fusion efficiency (X score, G2 = 2.4 +/- 0.163, G3 = 3.0 +/- 0, p

Nerve conduit is one of strategies for spine cord injury (SCI) treatment. Recently, studies showed that biomaterials could guide the neurite growth and promote axon regeneration at the injury site. However, the scaffold by itself was difficult to meet the need of SCI functional recovery. The basic fibroblast growth factor (bFGF) administration significantly promotes functional recovery after organ injuries. Here, using a rat model of T9 hemisected SCI, we aimed at assessing the repair capacity of implantation of collagen scaffold (CS) modified by collagen binding bFGF (CBD-bFGF). The results showed that CS combined with CBD-bFGF treatment improved survival rates after the lateral hemisection SCI. The CS/CBD-bFGF group showed more significant improvements in motor than the simply CS-implanted and untreated control group, when evaluated by the 21-point Basso-Beattie-Bresnahan (BBB) score and footprint analysis. Both hematoxylin and eosin (H&E) and immunohistochemical staining of neurofilament (NF) and glial fibrillary acidic protein (GFAP) demonstrated that fibers were guided to grow through the implants. These findings indicated that administration of CS modified with CBD-bFGF could promote spinal cord regeneration and functional recovery.