Overexpression of miR-۱۴۸a-۳p inhibits extracellular matrix degradation and alleviates IL-۱β-induced intervertebral disc degeneration

Objective(s): Recently, studies on microRNAs (miRNAs) and their targets and related genes have provided new therapeutic opportunities for controlling intervertebral disc degeneration (IDD). We aimed to investigate the effects of miR-۱۴۸a-۳p overexpression on IDD progression.Materials and Methods: This study used microRNA microarrays to analyze key regulators of IDD. Q-PCR was used to verify the IL-۱β-induced down-regulation of miR-۱۴۸a-۳p expression both in nucleus pulposus (NP) tissues of IDD patients and in degenerated NP cells (NPCs) of rats. Rat NPC micromass cultures and ex vivo intervertebral disc (IVD) culture models were established, and histological staining was performed to verify the effect of miR-۱۴۸a-۳p on the general morphology and proteoglycan and collagen contents of IVDs. In addition, q-PCR and western blotting analyses were performed to examine the expression of ECM molecules and matrix-degrading enzymes. A luciferase reporter assay was used to confirm the target genes of miR-۱۴۸a-۳p.Results: Our data revealed that miR-۱۴۸a-۳p was down-regulated in IDD. Overexpression of miR-۱۴۸a-۳p had no effect on ACAN or COL۲A۱ gene expression but decreased MMP۳, MMP۱۳, and ADAMTS۵ gene expression. The matrix deposited by miR-۱۴۸a-۳p-overexpressing rat NPCs contained high levels of proteoglycans and collagen. The ex vivo experiments verified that agomiR-۱۴۸a-۳p alleviated the NPC matrix degradation induced by IL-۱β. A luciferase reporter assay confirmed that miR-۱۴۸a-۳p directly targeted ADAMTS۵ and MMP۱۳.Conclusion: We proved that miR-۱۴۸a-۳p can attenuate ECM loss and protect NP function by inhibiting matrix-degrading enzymes.

کلیدواژه ها:

Extracellular matrix ، Intervertebral disc microRNAs ، miR-۱۴۸a-۳p ، Nucleus pulposus