小檗胺通过抑制JAK2/STAT3信号通路改善小鼠溃疡性结肠炎

Berberine improves ulcerative colitis in mice by inhibiting JAK2/STAT3 signal pathway

目的:观察小檗胺(BBM)对葡聚糖硫酸钠(DSS)诱导的溃疡性结肠炎(UC)小鼠的干预作用及其可能机制。方法:(1)采用RAW264.7巨噬细胞炎症模型,考察BBM对其细胞活力、一氧化氮(NO)释放、肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、IL-6和诱导型NO合酶(iNOS)炎症基因表达的影响。(2)雄性C57BL/6小鼠随机分为正常组、模型组、BBM组(50 mg/kg)和柳氮磺胺吡啶(SASP)阳性药组(250 mg/kg),每组8只。建立DSS诱导的UC小鼠模型,连续9 d灌胃给予相应药物。记录小鼠的体质量、脾脏系数、结肠长度及表观,评估疾病活动指数,HE染色观察结肠病理损伤;RT-qPCR检测小鼠结肠中炎症基因TNF-α、IL-1β、IL-6、iNOS的表达;Western blot检测小鼠结肠中紧密连接蛋白Claudin-4、Occludin及JAK2/STAT3通路蛋白的表达。结果:(1)BBM对RAW264.7细胞活力没有明显影响(P>0.05),但能呈剂量依赖性地减少细胞中NO的释放量(P<0.05,P<0.01)及炎症基因TNF-α、IL-1β、IL-6、iNOS的表达(P<0.05,P<0.01);(2)BBM能改善UC小鼠的体质量下降和脾脏系数升高(P<0.05)、抑制结肠的缩短(P<0.05)、降低疾病活动指数评分和改善结肠病理损伤(P<0.05);(3)BBM能减少小鼠结肠中炎症基因TNF-α、IL-1β、IL-6、iNOS的表达(P<0.05,P<0.01);(4)BBM能增加小鼠结肠中Claudin-4、Occludin的表达以及抑制JAK2和STAT3的磷酸化(P<0.05,P<0.01)。结论:BBM能改善DSS诱导小鼠的UC,其作用机制可能为通过抑制JAK2/STAT3信号通路、减少炎症基因的表达,从而增强肠黏膜屏障功能。

Objective:To observe the intervention effect and possible mechanism of berbamine(BBM)on ulcerative colitis(UC)mice induced by dextran sulfate sodium(DSS).Methods:ORAW264.7 macrophage inflammation model was used to investigate the effect of BBM on its cell viability,nitric oxide(NO)release,and the expression of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6 and inducible NO synthase(iNOS)inflammatory genes.②Male C57BL/6 mice were randomly divided into normal group,model group,BBM group(50 mg/kg)and sulfasalazine(SASP)positive group(250 mg/kg),with 8 mice in each group.DSS induced UC mouse model was established,and corresponding drugs were given by gavage for 9 d consecutively.The body mass,spleen coefficient,colon length and appearance of the mice were recorded,disease activity index was evaluated,and pathological injury of colon was observed by HE staining.The expression of inflammatory genes TNF-α,IL-Iβ,IL-6 and iNOS in the colon of mice were detected by RT-qPCR and the expression of tight junction proteins Claudin-4 and Occludin as well as JAK2/STAT3 pathway proteins were detected by Western blot.Results:BBM had no effect on RAW264.7 cells viability,but could reduce the NO release(P<0.05,P<0.01)and the expression of inflammatory genes TNF-α,IL-1β,IL-6 and iNOS in a dose-dependent manner(P<0.05,P<0.01).②BBM could improve the body mass loss and spleen coefficient increase of UC mice(P<0.05),inhibit the shortening of the colon(P<0.05),decrease the score of disease activity index and improve the pathological injury of colon in mice(P<0.05).BBM could reduce the expression of inflammatory genes TNF-α,IL-1β,IL-6 and iNOS in the colon of mice(P<0.05,P<0.01).BBM could increase the expression of Claudin-4 and Occludin,and reduce the phosphorylation of JAK2 and STAT3 in the colon of mice(P<0.05,P<0.01).Conclusion:BBM can improve UC in mice induced by DSS,its mechanism may be related to the inhibition of JAK2/STAT3 signal pathway and the reduction of inflammatory genes expression,thus enhancing the intestinal mucosal barrier function.