背景:颞下颌关节骨关节炎(TMJOA)是一种退行性软骨疾病。17β-雌二醇(E2)加重TMJOA的病理过程;然而,其作用机制尚未阐明。因此,我们研究了E2对滑膜细胞生物学行为的影响及其分子机制。
方法:用TNF-α处理大鼠原代成纤维样滑膜细胞,建立细胞模型,和表型使用细胞计数试剂盒-8,EdU,坦斯韦尔,酶联免疫吸附测定,和定量实时PCR(qPCR)。E2,FTO介导的NLRC5m6A甲基化的潜在机制,使用微阵列评估,甲基化RNA免疫沉淀,qPCR,和westernblot.此外,通过关节内注射碘乙酸钠(MIA)建立TMJOA样大鼠模型,采用显微CT和H&E染色评估骨形态和病理。
结果:结果表明E2促进了增殖,迁移,入侵,和TNF-α处理的FLS的炎症。FTO表达在TMJOA中下调,在FLS中被E2降低。FTO的敲低促进了NLRC5的m6A甲基化并通过IGF2BP1识别增强了NLRC5的稳定性。此外,E2促进TMJ病理和髁突重塑,骨矿物质密度和骨小梁体积分数增加,通过NLRC5击倒获救。
结论:E2促进了TMJOA的进展。
BACKGROUND: Temporomandibular joint osteoarthritis (TMJOA) is a degenerative cartilage disease. 17β-estradiol (E2) aggravates the pathological process of TMJOA; however, the mechanisms of its action have not been elucidated. Thus, we investigate the influence of E2 on the cellular biological behaviors of synoviocytes and the molecular mechanisms.
METHODS: Primary fibroblast-like synoviocytes (FLSs) isolated from rats were treated with TNF-α to establish cell model, and phenotypes were evaluated using cell counting kit-8, EdU, Tanswell, enzyme-linked immunosorbent assay, and quantitative real-time PCR (qPCR). The underlying mechanism of E2, FTO-mediated
NLRC5 m6A methylation, was assessed using microarray, methylated RNA immunoprecipitation, qPCR, and western blot. Moreover, TMJOA-like rat model was established by intra-articular injection of monosodium iodoacetate (MIA), and bone morphology and pathology were assessed using micro-CT and H&E staining.
RESULTS: The results illustrated that E2 facilitated the proliferation, migration, invasion, and inflammation of TNF-α-treated FLSs. FTO expression was downregulated in TMJOA and was reduced by E2 in FLSs. Knockdown of FTO promoted m6A methylation of
NLRC5 and enhanced
NLRC5 stability by IGF2BP1 recognition. Moreover, E2 promoted TMJ pathology and condyle remodeling, and increased bone mineral density and trabecular bone volume fraction, which was rescued by
NLRC5 knockdown.
CONCLUSIONS: E2 promoted the progression of TMJOA.