Sinapic acid (SA) was reported to protect against inflammation in various types of diseases. However, the role of SA in rheumatoid arthritis remains unclear. This study was designed to investigate the role of SA on rheumatoid arthritis. Rheumatoid arthritis mouse model was established by collagen immunization [collagen-induced arthritis (CIA)]. Histological analysis of articular cartilage tissue was carried out by hematoxylin and eosin (H&E) staining. Serum concentrations of tumor necrosis factor alpha and interleukin 6 were determined through enzyme-linked immunosorbent assay (ELISA). Oxidative damage indexes such as superoxide dismutase activity, malondialdehyde detection, glutathione detection, and catalase were determined by biochemical analysis. The protein levels of related genes were determined using Western blot. In CIA model, SA treatment attenuated paw swelling and clinical score of arthritis, attenuated articular cartilage tissues edema and infiltration of inflammatory cells, suppressed inflammatory cytokines release, and attenuated oxidative damage indexes. Mechanically, SA suppressed immune responses through inhibiting the IκB kinase (IKKs). SA attenuates rheumatoid arthritis through reducing inflammation and oxidative stress by downregulating IKKs.

中文翻译：

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芥子酸通过下调 IκB 激酶减少炎症和氧化应激来减轻类风湿性关节炎

据报道芥子酸 (SA) 可预防各种疾病的炎症。然而，SA 在类风湿性关节炎中的作用仍不清楚。本研究旨在调查 SA 在类风湿性关节炎中的作用。通过胶原免疫[胶原诱导的关节炎（CIA）]建立类风湿关节炎小鼠模型。通过苏木精和伊红（H＆E）染色进行关节软骨组织的组织学分析。通过酶联免疫吸附试验（ELISA）测定血清中肿瘤坏死因子α和白细胞介素6的浓度。生化分析测定超氧化物歧化酶活性、丙二醛检测、谷胱甘肽检测、过氧化氢酶等氧化损伤指标。使用Western印迹测定相关基因的蛋白质水平。在 CIA 模型中，SA 治疗减轻了爪肿胀和关节炎的临床评分，减轻了关节软骨组织水肿和炎性细胞的浸润，抑制了炎性细胞因子的释放，并减轻了氧化损伤指标。机械地，SA 通过抑制 IκB 激酶 (IKKs) 来抑制免疫反应。SA 通过下调 IKK 减少炎症和氧化应激来减轻类风湿性关节炎。