MicroRNAs associated with osteoarthritis differently expressed in bone matrix gelatin (BMG) rat model.

Osteoarthritis (OA) is characterized by degeneration of articular cartilage, limited intraarticular inflammation with synovitis, and changes in peri-articular and subchondral bone. In recent years, more and more evidence demonstrated that microRNAs (miRNAs) play important roles in the molecular mechanisms in OA by suppressing gene expression at the post-transcriptional level. In current study, histological staining of toluidine blue and cartilage-specific gene express revealed that the bone matrix gelatin (BMG) rat model could demonstrate the different development of cartilage. In current study, we tested whether some miRNAs associated with OA differently expressed in BMG rat model. We verified that miR-140 and miR-455 were associated with cartilage development, and further revealed that miR-140-5p and miR-455-3p might play more important function than miR-140-3p and miR-455-5p in the BMG rat model. Moreover, we found that miR-9 and miR-98 were involved in the endochondral ossification, suggesting they may be also the key regulators in the process of endochondral ossification. In fact, many miRNAs worked as a miRNA-mediated regulatory network in the process of cartilage development and OA. Further functional discovery will clarify the roles of individual miRNAs and their targets, and serve as a strong foundation for translating these findings to the clinic therapy for OA.