黄芩苷对复发性口腔溃疡模型大鼠IL-33/ST2信号通路的影响及机制研究

Effect of Baicalin on IL-33/ST2 Signaling Pathway in Rats with Recurrent Oral Ulcers and Its Mechanism

目的:探讨黄芩苷通过调控白细胞介素-33/肿瘤发生抑制蛋白2(IL-33/ST2)信号通路对复发性口腔溃疡(ROU)模型大鼠的治疗作用及其机制研究。方法:50只大鼠采用自体抗原注射法构建ROU模型,并将其随机分成模型组,低、中、高剂量黄芩苷(25、50、100mg/kg)组和左旋咪唑组(17.5mg/kg),另取10只仅注射弗氏完全佐剂的大鼠作为正常组。灌胃给药结束后,观察并记录各组大鼠溃疡数目、持续时间、间隔时间;流式细胞仪检测各组大鼠外周血T淋巴细胞亚群CD4^(+)、CD8^(+)含量;酶联免疫分析法检测各组大鼠血清中干扰素-γ(IFN-γ)、IL-17、IL-2、肿瘤坏死因子α(TNF-α)水平;还原型谷胱甘肽(GSH)、超氧化物歧化酶(SOD)、丙二醛(MDA)测试盒检测各组大鼠血清中GSH、SOD、MDA含量;免疫印迹法检测各组大鼠口腔黏膜组织中IL-33、ST2、核因子kB(NF-kB)蛋白水平。结果:与正常组相比,模型组大鼠溃疡数目增多,持续时间增加,间隔时间延长,CD4^(+)及CD4^(+)/CD8^(+)降低,CD8^(+)升高,IFN-γ、IL-17、IL-2、TNF-α、MDA含量增加,GSH、SOD含量减少,IL-33、ST2、NF-kB蛋白表达上调(P<0.05)。与模型组相比,低、中、高剂量黄芩苷组大鼠溃疡数目和持续时间减少,间隔时间延长,CD4^(+)及CD4^(+)/CD8^(+)增加,CD8^(+)减少,IFN-γ、IL-17、IL-2、TNF-α、MDA含量下降,GSH、SOD含量上升,IL-33、ST2、NF-kB蛋白表达下调(P<0.05),且呈现剂量依赖性。高剂量黄芩苷与左旋咪唑组的各项指标差异不具有统计学意义(P>0.05)。结论:黄芩苷对ROU模型大鼠有明显的治疗作用,可能抑制IL-33/ST2通路,调控T淋巴细胞亚群失衡,改善炎症反应和氧化损伤。

Objective:To investigate the therapeutic effect of baicalin on model rats with recurrent oral ulcer(ROU)and its mechanism by regulating the interleukin-33/suppression of tumorigenicity 2(IL-33/ST2)signaling pathway.Methods:Fifty rats were injected with autologous antigens to construct ROU models and randomly divided into model group,low,medium,and high dose baicalin(25,50,100 mg/kg)groups,and levamisole group(17.5 mg/kg);another 10 rats injected with Freund’s complete adjuvant were taken as the normal group.After the completion of intragastric administration,the number,duration and interval of ulcers of rats in each group were observed and recorded;flow cytometry was used to detect the contents of CD4and CD8T in lymphocyte subsets in the peripheral blood of rats in each group;enzyme-linked immunoassay was used to detect the levels of interferon-γ(IFN-γ),IL-17,IL-2,and tumor necrosis factor-α(TNF-α)in the serum of rats in each group;reduced glutathione(GSH),superoxide dismutase(SOD),malondialdehyde(MDA)test kits were used to detect the levels of GSH,SOD and MDA in the serum of rats in each group;Western blotting was used to detect the levels of IL-33,ST2,and nuclear factor-kB(NF-k B)protein in the oral mucosa tissues of rats in each group.Results:Compared with the normal group,the number of ulcers in the model group increased,the duration increased,and the interval time prolonged,the CD4and CD4/CD8decreased,the CD8increased,the contents of IFN-γ,IL-17,IL-2,TNF-α,and MDA increased,the contents of GSH and SOD reduced,the expression of IL-33,ST2,and NF-k B proteins was up-regulated(P<0.05).Compared with the model group,the number and duration of ulcers in the low,medium and high dose baicalin groups decreased,and the interval time prolonged,the CD4and CD4/CD8increased,the CD8,the contents of IFN-γ,IL-17,IL-2,TNF-α,and MDA decreased,the contents of GSH and SOD increased,the expression of IL-33,ST2,and NF-kB proteins was down-regulated(P<0.05),and they were dose-dependent.There was no statistically significant difference in indicators between the high-dose baicalin group and levamisole group(P>0.05).Conclusion:Baicalin has a significant therapeutic effect on ROU model rats.It may inhibit the IL-33/ST2 pathway,regulate the imbalance of T lymphocyte subsets,and improve inflammatory response and oxidative damage.