MicroRNA-127-5p Regulates Matrix Metalloproteinase 13 Expression and Interleukin-1β-Induced Catabolic Effects in Human Chondrocytes.

Objective MicroRNAs (miRNAs), small noncoding RNA molecules, are involved in the pathogenesis of various diseases such as cancer and arthritis. The aim of this study was to determine whether miR-127-5p regulates interleukin-1β (IL-1β)-induced expression of matrix metalloproteinase 13 (MMP-13) and other catabolic factors in human chondrocytes. Methods Expression of miR-127-5p and MMP-13 by normal and osteoarthritic (OA) human cartilage was determined using real-time polymerase chain reaction. The effect of miR-127-5p on MMP-13 expression was evaluated using transient transfection of human chondrocytes or chondrogenic SW-1353 cells with miR-127-5p or its antisense inhibitor (anti-miR-127-5p). MMP-13 protein production was quantified by enzyme-linked immunosorbent assay, and the involvement of miR-127-5p in IL-1β-mediated catabolic effects was examined by immunoblotting. MicroRNA-127-5p binding with the putative site in the 3′-untranslated region (3′-UTR) of MMP-13 messenger RNA (mRNA) was validated by luciferase reporter assay. Results There was a significant reduction in miR-127-5p expression in OA cartilage compared with normal cartilage. Up-regulation of MMP-13 expression by IL-1β was correlated with down-regulation of miR-127-5p expression in human chondrocytes. MicroRNA-127-5p suppressed IL-1β-induced MMP-13 production as well as the activity of a reporter construct containing the 3′-UTR of human MMP-13 mRNA. In addition, mutation of the miR-127-5p binding site in the 3′-UTR of MMP-13 mRNA abolished miR-127-5p-mediated repression of reporter activity. Conversely, treatment with anti-miR-127-5p remarkably increased reporter activity and MMP-13 production. Interestingly, the IL-1β-induced activation of JNK, p38, and NF-κB and expression of MMP-1 and cyclooxygenase 2 were significantly inhibited by miR-127-5p. Conclusion MicroRNA-127-5p is an important regulator of MMP-13 in human chondrocytes and may contribute to the development of OA. [ABSTRACT FROM AUTHOR]