Exploration of the Effect of mmu-miR-142-5p on Osteoblast and the Mechanism

The objective of this study is to explore the effect of mmu-miR-142-5p on osteoblast and the mechanism. Neonatal New Zealand rabbits were selected to collect and culture primary osteoblasts after being killed. The agonists agomiR-142-5p, agomiR-NC and inhibitors antagomiR-142-5p, antagomiR-NC were transfected to establish mmu-miR-142-5p osteoblast model. 48 h after transfection, total RNA was extracted, ELISA was used to detect ALP level, Western Blot was used to detect HSP27 level, and RT-PCR was used to detect levels of RunX2 and OC. Rabbit osteoblasts showed triangle shape and grew adhering to the wall, cytoplasm extended and protruded. As the culture time prolonged, the cell volume was increased, and the amount showed exponential growth. After transfection, the abundance was significantly increased in agonist group and significantly decreased in inhibitor group, indicating that exogenous agonist can successfully up-regulate mmu-miR-142-5p level and exogenous inhibitor can down-regulate mmu-miR-142-5p level in osteoblast. Compared with control group, ALP level was significantly increased in agonist group and decreased in inhibitor group. Transfection of exogenous agonist can up-regulate HSP27 level in osteoblast, and transfection of exogenous inhibitor can decrease HSP27 level in osteoblast; however, there was no effect on HSP27 mRNA level. RunX2 mRNA and OC mRNA were significantly increased in agonist group and decreased in inhibitor group. Transfection of exogenous nucleic acid agomiR-142-5p can up-regulate the abundance and activity of mmu-miR-142-5p, and transfection of antagomiR-142-5p can down-regulate the abundance and activity of mmu-miR-142-5p, indicating that mmu-miR-142-5p can effectively helps the mineralization of osteoblast.