MicroRNAs (miRNAs), small noncoding RNA molecules, have emerged as important factors during intervertebral disc degeneration. This study was to determine whether miR-202-3p regulates interleukin-1β (IL-1β)-induced expression of matrix metalloproteinase 1 (MMP-1) in human nucleus pulposus (NP) cells. Human NP cells were stimulated with IL-1β in vitro. MicroRNA arrays were used to determine the expression profile of 1971 human miRNAs and the miRNAs targets were identified using bioinformatics. In IL-1β-stimulated NP cells, 10 microRNAs were down-regulated, 2 microRNAs were up-regulated. There was a significant reduction in hsa-miR-202-3p (miR-202-3p) expression in the severe degenerative disc compared with mi... More
MicroRNAs (miRNAs), small noncoding RNA molecules, have emerged as important factors during intervertebral disc degeneration. This study was to determine whether miR-202-3p regulates interleukin-1β (IL-1β)-induced expression of matrix metalloproteinase 1 (MMP-1) in human nucleus pulposus (NP) cells. Human NP cells were stimulated with IL-1β in vitro. MicroRNA arrays were used to determine the expression profile of 1971 human miRNAs and the miRNAs targets were identified using bioinformatics. In IL-1β-stimulated NP cells, 10 microRNAs were down-regulated, 2 microRNAs were up-regulated. There was a significant reduction in hsa-miR-202-3p (miR-202-3p) expression in the severe degenerative disc compared with mild degenerative disc. Down-regulation of miR-202-3p expression by IL-1β was correlated with up-regulation of MMP-1 expression in human NP cells. IL-1β-induced activation of MAP kinase (MAPK) and nuclear factor-κB (NF-κB) decreased miR-202-3p expression and induced MMP-1 expression. MiR-202-3p suppressed IL-1β-induced MMP-1 production. Conversely, treatment with anti-miR-202-3p remarkably increased MMP-1 production. In addition, mutation of the miR-202-3p binding site in the 3'-UTR of MMP-1 mRNA abolished miR-202-3p-mediated repression of reporter activity. Functional analysis showed that miR-202-3p could decrease type II collagen degradation, whereas overexpression of MMP-1 by Lentiviral-shMMP-1 abolished the effect of miR-202-3p on type II collagen degradation. These results suggest that miR-202-3p is an important regulator of MMP-1 in human nucleus pulposus and may contribute to the development of intervertebral disc degeneration.,Copyright © 2018 Elsevier B.V. All rights reserved.