MiR-15a-5p regulates viability and matrix degradation of human osteoarthritis chondrocytes via targeting VEGFA.

Previous studies demonstrated that miR-15a-5p was probably associated with human hepatocellular carcinoma, while the function of miR-15a-5p in OA (Osteoarthritis) still remains unknown. Here, we uncovered the potential role of miR-15a-5p on OA pathogenesis and confirmed its predicted target VEGFA (Vascular Endothelial Growth Factor A). Measured by RT-PCR, miR-15a-5p expression increased remarkably while VEGFA expression was significantly decreased in OA chondrocytes compared with normal conditions. According to Luciferase activity assay, miR-15a-5p directly targeted the 3'-UTR of VEGFA to inhibit its expression. Functional analysis including CCK-8 assay and flow cytometry revealed that overexpression of VEGFA or inhibition of miR-15a-5p promoted cell proliferation, suppressed cell apoptosis and reduced matrix degradation in OA chondrocytes. Moreover, rescue assays carried out with both expression of VEGFA and miR-15a-5p demonstrated that miR-15a-5p contributes to cell apoptosis and matrix degradation via inhibiting VEGFA. We further provided evidence that multiple proteins related to matrix synthesis were regulated by miR-15a-5p and VEGFA using Western blot and ELISA assays. Taken together, our findings elucidated an underlying mechanism by which miR-15a-5p regulates viability and matrix degradation of OA and indicated a new target for OA diagnosis and therapy.