Extract of Plastrum Testudinis through miR-214 mediated Wnt/β-catenin signaling stimulating bone formation

Abstract: Plastrum Testudinis (PT) is known as Traditional Chinese Medicine, which has commonly been used to treat and prevent bone metabolism for many years. However, the pharmacological mechanisms have not yet been fully clarified. In this study, we constructed a bilateral ovariectomy model to simulate postmenopausal osteoporosis (OP), then performed intragastric administration of different doses (160, 80, 40 mg/kg/day) of PT for 10 weeks. After treatment, we used dual-energy X-ray absorptiometry to evaluate bone mineral density, and micro-computed tomography and hematoxylin and eosin staining to analyze bone microstructure, immunochemistry, western blotting and quantitative polymerase chain reaction to detect the expression of osteogenic differentiation-related factors; and miRNA over-expression to evaluate the effect of miR-214 on the differentiation of bone mesenchymal stem cells (BMSCs) and related target genes. PT moderated bone mass and bone microstructure, alleviated body weight, and exhibited no estrogen-like effects; promoted the expression of osteogenic differentiation factors in the femur and lumbar vertebrae, as well as facilitated the expression of the Wnt signaling-related factors LRP5, Wnt3a, GSK-3β, and β-catenin. In addition, miR-214 inhibited osteogenic differentiation of BMSCs and targeted the Wnt signaling-related factors Wnt3a and β-catenin, while PT ameliorated these effects. This study indicated that PT may act as an antagonist of miR-214 to stimulate bone formation through β-catenin-mediated Wnt signaling.