LncRNA FGD5-AS1 promotes osteogenic differentiation of human bone marrow mesenchymal stem cells by regulating miR-93-5p/BMP2 axis

Objective To investigate the impact of long non-coding RNA (lncRNA) FGD5-AS1 on the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) through regulation of the microRNA miR-93-5p/bone morphogenetic protein-2(BMP2) axis. Methods hBM-MSCs in logarithmic growth phase were taken, and the expression levels of lncRNA FGD5-AS1, miR-93-5p and BMP2 mRNA were detected before and after osteogenic differentiation; The cells were transfected or co-transfected with pcDNA FGD5-AS1, miR-93-5p inhibitor, miR-93-5p mimics and corresponding negative controls, respectively, then divided into pcDNA NC group, pcDNA FGD5-AS1 group, inhibitor NC group, miR-93-5p inhibitor group, pcDNA FGD5-AS1+mimics NC group, or pcDNA FGD5-AS1+miR-93-5p mimics group and non-transfected cells were taken as blank group. CCK-8 assay was applied to detect cell proliferation ability of each group; Alkaline phosphatase (ALP) kit was applied to detect its activity; Alizarin red staining was applied to identify cellular mineralized nodule formation; Western blot was applied to detect the levels of BMP2, osteogenesis-related markers-osteocalcin (OCN), osteopontin (OPN), and osterix(OSX); Dual-luciferase experiment was applied to verify the targeting relationship of miR-93-5p with FGD5-AS1 and BMP2, respectively. Results lncRNA FGD5-AS1 and BMP2 were found to be targets of miR-93-5p. After osteogenic differentiation, the expression of FGD5-AS1 and BMP2 was increased and the expression of miR-93-5p was decreased (P＜0.05). Compared with pcDNA NC group, the expression of FGD5-AS1 in pcDNA FGD5-AS1 group was significantly increased(P＜0.05), indicating successful transfection; Mineralized nodules, cell proliferation, ALP activity and the expression of BMP2, OCN, OPN and OSX were obviously higher (P＜0.05) in pcDNA FGD5-AS1 group. Compared with the inhibitor NC group, the expression of miR-93-5p in miR-93-5p inhibitor group was significantly decreased (P＜0.05), indicating successful transfection; Mineralized nodules, cell proliferation, ALP activity and the expression of BMP2, OCN, OPN and OSX were obviously improved (P＜0.05) in miR-93-5p inhibitor group. Over-expression of miR-93-5p inhibited the promoting effect of FGD5-AS1 on the osteogenic differentiation of hBM-MSCs(P＜0.05). Conclusions Up-regulation of FGD-AS1 promotes the osteogenic differentiation of hBM-MSCs, which might be related to the miR-93-5p/BMP2 axis

Cooperated control strategy of generator re-dispatching and multi-HVDC modulation after ultra HVDC block

With the increase of DC project voltage level and transmission capacity, the security and stability risk caused by DC blocking is gradually increasing. Aiming at reserve dispatch after ultra-high voltage direct current (UHVDC) block, scenarios of DC power modulation participating in dispatching are presented. Mathematical models of generator re-dispatching incorporated control of DC in AC/DC hybrid grid in three situations in terms of enough reserve capacity in the disturbed province, regional reserve capacity sufficient and insufficient to make up for the power deficiency are presented. Then, a decision-aid system for optimal reserve dispatch after UHVDC block is proposed. Simulation results of Central China power grid indicate that the proposed scheduling scheme can reduce the operation risks of security and load loss if necessary