Lei Yu, Zhan Enyu, Chen Chao, Hu Yaoquan, Lv Zhengpin, He Qicong, Wang Xuenan, Li Xingguo, Zhang Fan
Department of Orthopedics, The First Affiliated Hospital of Kunming Medical University, 295 Xichang Rd, Wuhua District, Kunming, Yunnan, 650032, China.
Cell Biosci. 2024 Jun 14;14(1):79. doi: 10.1186/s13578-024-01264-y.
BACKGROUND: N6-methyladenosine (mA) methylation is a prevalent RNA modification implicated in various diseases. However, its role in intervertebral disc degeneration (IDD), a common cause of low back pain, remains unclear. RESULTS: In this investigation, we explored the involvement of mA demethylation in the pathogenesis of IDD. Our findings revealed that ALKBH5 (alkylated DNA repair protein AlkB homolog 5), an mA demethylase, exhibited upregulation in degenerative discs upon mild inflammatory stimulation. ALKBH5 facilitated mA demethylation within the three prime untranslated region (3'-UTR) of Runx2 mRNA, consequently enhancing its mRNA stability in a YTHDF1 (YTH N6-methyladenosine RNA binding protein F1)-dependent manner. The subsequent elevation in Runx2 expression instigated the upregulation of ADAMTSs and MMPs, pivotal proteases implicated in extracellular matrix (ECM) degradation and IDD progression. In murine models, subcutaneous administration of recombinant Runx2 protein proximal to the lumbar disc in mice elicited complete degradation of intervertebral discs (IVDs). Injection of recombinant MMP1a and ADAMTS10 proteins individually induced mild to moderate degeneration of the IVDs, while co-administration of MMP1a and ADAMTS10 resulted in moderate to severe degeneration. Notably, concurrent injection of the Runx2 inhibitor CADD522 with recombinant Runx2 protein did not result in IVD degeneration in mice. Furthermore, genetic knockout of ALKBH5 and overexpression of YTHDF1 in mice, along with lipopolysaccharide (LPS) treatment to induce inflammation, did not alter the expression of Runx2, MMPs, and ADAMTSs, and no degeneration of the IVDs was observed. CONCLUSION: Our study elucidates the role of ALKBH5-mediated mA demethylation of Runx2 mRNA in activating MMPs and ADAMTSs, thereby facilitating ECM degradation and promoting the occurrence of IDD. Our findings suggest that targeting the ALKBH5/Runx2/MMPs/ADAMTSs axis may represent a promising therapeutic strategy for preventing IDD.
背景:N6-甲基腺苷(mA)甲基化是一种普遍存在的RNA修饰,与多种疾病有关。然而,其在椎间盘退变(IDD)(下腰痛的常见原因)中的作用仍不清楚。 结果:在本研究中,我们探讨了mA去甲基化在IDD发病机制中的作用。我们的研究结果表明,mA去甲基化酶ALKBH5(烷基化DNA修复蛋白AlkB同源物5)在轻度炎症刺激下在退变椎间盘中表达上调。ALKBH5促进Runx2 mRNA 3'非翻译区(3'-UTR)内的mA去甲基化,从而以YTHDF1(YTH N6-甲基腺苷RNA结合蛋白F1)依赖的方式增强其mRNA稳定性。Runx2表达的随后升高促使ADAMTSs和MMPs上调,这两种关键蛋白酶与细胞外基质(ECM)降解和IDD进展有关。在小鼠模型中,在小鼠腰椎间盘附近皮下注射重组Runx2蛋白导致椎间盘(IVD)完全降解。单独注射重组MMP1a和ADAMTS10蛋白可诱导IVD轻度至中度退变,而同时注射MMP1a和ADAMTS10则导致中度至重度退变。值得注意的是,将Runx2抑制剂CADD522与重组Runx2蛋白同时注射不会导致小鼠IVD退变。此外,在小鼠中对ALKBH5进行基因敲除和YTHDF1过表达,以及用脂多糖(LPS)治疗诱导炎症,均未改变Runx2、MMPs和ADAMTSs的表达,也未观察到IVD退变。 结论:我们的研究阐明了ALKBH5介导的Runx2 mRNA的mA去甲基化在激活MMPs和ADAMTSs中的作用,从而促进ECM降解并促进IDD的发生。我们的研究结果表明,靶向ALKBH5/Runx2/MMPs/ADAMTSs轴可能是预防IDD的一种有前景的治疗策略。
Clin Chim Acta. 2015-8-25
J Orthop Translat. 2025-6-5
Oxid Med Cell Longev. 2022
Orthop Surg. 2022-7
Int J Mol Sci. 2022-2-2
Mol Neurobiol. 2022-3