microRNA-1236 promotes chondrocyte apoptosis in osteoarthritis via direct suppression of PIK3R3

Aims Chondrocyte degeneration is the main cause of osteoarthritis (OA) and increased evidence suggests that miRNAs could have vital roles in the pathology of various cartilage illnesses. miR-1236 has been found to contribute to inflammation in diseases such as pneumonia. However, the exact role of miR-1236 in OA is poorly understood. Materials and methods H&E staining and saffron fixation experiments were employed to determine OA tissues. qRT-PCR and immunohistochemistry were used to detect the expression levels of miR-1236 and PIK3R3. Western blot was performed to detect the expression levels of proteins. Luciferase reporter assays were utilized to investigate the interaction between miR-1236 and PIK3R3. Cell counting assays and AO/EB were used to quantify cell growth and apoptosis. Key findings miR-1236 was up-regulated in OA knee cartilage compared to normal cartilage. Up-regulated expression of miR-1236 suppressed cell proliferation as well as induced apoptosis in chondrocytes. Bioinformatics identified PIK3R3 as a target of miR-1236. Co-transfection with miR-1236 and PIK3R3 could reverse cell apoptosis induced by the miR-1236 mimic. Significance These data enhance our understanding on the role of miR-1236 in OA and identifies miR-1236 as a potential biomarker or possible treatment target within OA.