miR-34a-5p facilitates osteogenic differentiation of bone marrow mesenchymal stem cells and modulates bone metabolism by targeting HDAC1 and promoting ER-α transcription

Metabolism is essential for bone development. The expressions of catabolic markers in chondrocytes show association with miR-34a-5p. This study discussed the mechanism by which miR-34a-5p regulates osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) as well as bone metabolism.Expressions of BMSC surface markers were determined via flow cytometry. Osteogenic differentiation of BMSCs was subsequently induced. miR-34a-5p mimic, oe-HDAC1, or ER-α activator Ferutinin was introduced in BMSCs. Alkaline phosphatase activity and calcification were detected. Expressions of miR-34a-5p, HDAC1, ER-α, and osteogenic markers were determined via RT-qPCR and Western blot. The binding relationship between miR-34a-5p and HDAC1 was verified by a dual-luciferase assay. Mice at the age of 6 months and 18 months were assigned to the young group and age group for in vivo experiments, and aged mice were treated with agomiR miR-34a-5p. Expressions of serum miR-34a-5p, HDAC1, ER-α, and bone metabolism markers in mice were determined.Osteogenic medium-induced BMSCs manifested increased expressions of miR-34a-5p and ER-α and decreased HDAC1 expression. miR-34a-5p overexpression promoted osteogenic differentiation of BMSCs. miR-34a-5p targeted HDAC1. HDAC1 overexpression partially counteracted the promotional action of miR-34a-5p overexpression on osteogenic differentiation of BMSCs. miR-34a-5p overexpression activated ER-α. ER-α activator Ferutinin partially nullified the regulatory function of miR-34a-5p/HDAC1 on osteogenic differentiation of BMSCs. In vivo experiments showed that miR-34a-5p overexpression enhanced the potential of bone metabolism in aged mice.miR-34a-5p overexpression promoted osteogenic differentiation of BMSCs and enhanced bone metabolism by promoting ER-α activation via targeting HDAC1.