Inhibition of microRNA-30d attenuates the apoptosis and extracellular matrix degradation of degenerative human nucleus pulposus cells by up-regulating SOX9

In this study, we aimed to investigate the role of miR-30d in regulating apoptosis and the extracellular matrix degradation of NP cells, along with the potential underlying molecular mechanism. Herein, our results showed that miR-30d was significantly increased in degenerative NP tissues compared with normal controls. Functional experiments showed that the inhibition of miR-30d promoted the viability and reduced the apoptosis of NP cells in vitro. Moreover, miR-30d inhibition increased the expression of type II collagen and aggrecan and inhibited the expression of matrix metalloproteinase. In contrast, the overexpression of miR-30d showed the opposite effects. Bioinformatics analysis, the dual-luciferase reporter assay, real-time quantitative PCR and western blot analysis showed that miR-30d directly targeted the 3′-untranslated region of SRY-related high mobility group box 9 (SOX9) and negatively regulated SOX9 expression. Correlation analysis showed that miR-30d expression was inversely correlated with SOX9 expression in degenerative NP tissues. Moreover, siRNA-mediated silencing of SOX9 expression significantly blocked the protective effects of miR-30d inhibition against NP cell apoptosis and extracellular matrix degradation. Overall, these results demonstrate that the inhibition of miR-30d attenuates the apoptosis and extracellular matrix degradation of degenerative human NP cells by up-regulating SOX9, suggesting a potential therapeutic target for IDD.Graphical abstrac...
Source: Chemico Biological Interactions - Category: Biochemistry Source Type: research