Wang Gang, Zhang Lecheng, Yan Chao, Wang Fengbin, Zhang Yuelei
Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, People's Republic of China.
Diabetes Metab Syndr Obes. 2021 Feb 15;14:671-682. doi: 10.2147/DMSO.S288338. eCollection 2021.
Postmenopausal osteoporosis is one of the most common types of osteoporosis that women suffer from. Studies involving molecular mechanisms for designing better therapeutic strategies for postmenopausal osteoporosis are still rare. The present study investigates the role of miR-125b in postmenopausal osteoporosis.
Microarray analysis was done to screen the gene database. Tissue samples of postmenopausal women were collected to study the miRNA profiles. MC3T3-E1 cells were used and were submitted for transfection. CCK-8 assay was done to check the viability of cells, whereas toxicity was done by lactate dehydrogenase assay kit. TargetScan was done to target genes of miR-125b followed by confirmation by Luciferase reporter assay. For animal studies a rat model of ovariectomized rats was created. Bone mineral density and biomechanics were measured by densitometer. The mRNA levels were assessed by qRT-PCR and proteins by Western blot assay.
miR-125b was over-expressed in human osteoporosis samples. In vitro studies suggested that miR-125b suppressed the cell viability and promoted release of LDH, it also enhanced the RANKL/OPG ratio and suppressed levels of BMP2 and Runx2. Bioinformatics identified TRAF6 as a potential target of miR-125b, further confirmed by luciferase assay, also miR-125b negatively regulated the levels of TRAF6 gene in osteoporosis bones involving the JAK2/STAT3 cascade. In the rat model, miR-125b decreased the bone mineral density and biomechanical parameters in bones by altering the TRAF6 gene involving the JAK2/STAT3 pathway.
The outcomes suggested that miR-125b was responsible for the development of postmenopausal osteoporosis and promoted its progression by the TRAF6 gene via the JAK2/STAT3 pathway.
绝经后骨质疏松症是女性患有的最常见的骨质疏松症类型之一。涉及为绝经后骨质疏松症设计更好治疗策略的分子机制的研究仍然很少。本研究调查了miR-125b在绝经后骨质疏松症中的作用。
进行微阵列分析以筛选基因数据库。收集绝经后妇女的组织样本以研究miRNA谱。使用MC3T3-E1细胞并进行转染。进行CCK-8测定以检查细胞活力，而使用乳酸脱氢酶测定试剂盒进行毒性测定。使用TargetScan确定miR-125b的靶基因，随后通过荧光素酶报告基因测定进行确认。对于动物研究，创建了去卵巢大鼠的大鼠模型。通过骨密度仪测量骨矿物质密度和生物力学。通过qRT-PCR评估mRNA水平，通过蛋白质印迹法评估蛋白质水平。
miR-125b在人类骨质疏松症样本中过表达。体外研究表明，miR-125b抑制细胞活力并促进LDH释放，还提高RANKL/OPG比率并抑制BMP2和Runx2水平。生物信息学确定TRAF6为miR-125b的潜在靶标，荧光素酶测定进一步证实，此外，miR-125b通过涉及JAK2/STAT3级联反应的途径负调控骨质疏松症骨骼中TRAF6基因的水平。在大鼠模型中，miR-125b通过改变涉及JAK2/STAT3途径的TRAF6基因降低了骨骼中的骨矿物质密度和生物力学参数。
结果表明，miR-125b导致绝经后骨质疏松症的发生，并通过TRAF6基因经由JAK2/STAT3途径促进其进展。
