对羟基苯甲酸通过抑制NF-κB/caspase-1信号通路抗类风湿性关节炎的研究

目的 探讨天然酚酸类化合物对羟基苯甲酸（p-hydroxybenzoic acid，HA）对完全弗氏佐剂（complete Freund’s adjuvant，CFA）诱导的佐剂性关节炎（adjuvant arthritis，AA）模型的治疗作用，并对HA的作用机制进行初步分析。方法 除正常组外，向大鼠足跖皮内注射CFA 0.1 mL诱导AA大鼠模型。将AA模型大鼠随机分为模型组，HA低、中、高剂量组（2.5，5，10 mg·kg^-1）和阳性药物组（吲哚美辛，5 mg·kg^-1），灌胃给予药物进行治疗干预，记录每组大鼠足肿胀体积、足肿胀厚度并进行关节肿胀评分；通过ELISA和qPCR检测不同剂量HA对炎症因子（TNF-α、IL-1β、IL-6）表达的影响；采用X-射线和HE染色观察足爪组织形态学和病理学变化；Western blotting检测caspase-1和NF-κB的表达。结果 HA能减轻AA大鼠关节肿胀（P<0.05）；从蛋白质和mRNA水平显著抑制炎症因子（TNF-α、IL-1β、IL-6）的产生（P<0.05），并显著降低caspase-1和NF-κB蛋白表达水平；X-射线显示HA能减轻大鼠踝关节损伤，HE染色结果显示HA能显著抑制炎症细胞的浸润和软骨表层破坏等情况（P<0.05），且这些结果均呈剂量依赖性。结论 HA可能通过抑制NF-κB/caspase-1信号通路缓解关节炎症状。

Study on p-Hydroxybenzoic Acid on Rheumatoid Arthritis Via Inhibiting NF-κB/caspase-1 Signaling Pathway

OBJECTIVE To investigate the therapeutic effect of natural phenolic compound p-hydroxybenzoic acid(HA) on adjuvant arthritis(AA) induced by the complete Freund's adjuvant(CFA), and to clarify the mechanism of HA preliminary. METHODS Apart from the normal group, all rats received 0.1 mL CFA by plantar subcutaneous injection to induce AA rats model. And rats with AA were randomized to the model group, the low-, medium-, and high-dose HA group(2.5, 5, and 10 mg·kg^-1, respectively), the positive control group(indomethacine, 5 mg·kg^-1). The rats in each group were orally treated with the corresponding drugs for therapeutic intervention. The volume and leg thickness of the rats in each group were recorded and an inflated articular score was obtained. Inflammation cytokine expression(TNF-α, IL-1β and IL-6) was determined by ELISA and qPCR. Radiographs and HE staining were used to observe histopathological and pathological changes in the foot. The expressions of caspase-1 and NF-κB were examined in Western blotting. RESULTS HA could significantly alleviate joint swelling in AA rat(P<0.05), inhibited the production of inflammatory factors(TNF-α, IL-1β and IL-6) from protein and mRNA levels(P<0.05), and decreased the expression levels of caspase-1 and NF-κB at protein level(P<0.05). HA alleviated ankle injury in rats by X-ray examination, and HE staining showed that HA could significantly inhibit the infiltration of inflammatory cells and the destruction of cartilage surface(P<0.05), and these results were dose-dependent. CONCLUSION HA may relieve rheumatoid arthritis by inhibiting the NF-κB/casepase-1 signaling pathway.