苍防汤对DSS诱导的大鼠溃疡性结肠炎保护作用研究

Research on Protective Effect of Cangfang Decoction on DSS Induced by Ulcerative Colitis Rats

目的:采用硫酸葡聚糖(dextran sulfate sodium,DSS)建立大鼠溃疡性结肠炎模型,观察苍防汤对其治疗作用及其机制。方法:用5%的DSS水溶液连续喂养3月龄雄性SD大鼠5 d,建立溃疡性结肠炎大鼠模型。建模成功后灌胃给予低剂量(1.0 g·kg^(-1)·d^(-1))和高剂量(10.0 g·kg^(-1)·d^(-1))的苍防汤提取物冻干粉溶液,以柳氮磺胺吡啶(sulfasalazine,SASP)为阳性对照连续给予相应药物2周。每天记录大鼠体质量、粪便状态以及便血情况等指标,评估疾病活动指数;实验结束后检测结肠的肠黏膜损伤指数及损伤程度评分;HE染色检测结肠组织病理学变化;免疫组化染色检测凋亡蛋白Cleaved-caspase-3的表达;定量PCR检测结肠组织中IL-1、IL-6、IL-10、TNF-α、IFN-γ及MUC2的mRNA水平;Western blot检测结肠组织中MUC2蛋白的表达水平。结果:苍防汤有效改善DSS诱导的结肠炎大鼠的疾病活动指数,减轻结肠的溃疡性损伤;改善DSS引起的结肠部位炎性浸润和隐窝破坏,抑制细胞凋亡并降低组织中IL-1、IL-6、TNF-α及IFN-γ的mRNA表达水平,升高MUC2和IL-10的mRNA表达水平及MUC2的蛋白表达水平。结论:苍防汤能有效改善DSS诱导的大鼠溃疡性结肠炎,其作用机制可能与调节炎症反应及抑制凋亡有关,为临床治疗溃疡性结肠炎提供分子生物学基础。

Objective:To explore the treatment effect of Cangfang Decoction on rats with ulcerative colitis(UC)induced by dextran sulfate sodium(DSS)and research its potential mechanism.Methods:Rat UC model was established by 5%DSS administration in male SD rats for 5 days.After successful modeling,low-dose(1.0 g·kg^(-1)·d^(-1))and high-dose(10.0 g·kg^(-1)·d^(-1))freeze-dried powder solutions of Cangfang decoction extract were given by gavage,with sulfasalazine(SASP)as the Positive control.The disease activity index was evaluated according to weight loss,stool formation,and fecal blood.At the end of the experiment,the intestinal mucosal injury index and degree were detected;Histopathological changes were detected by HE staining,the expression of cleaved-caspase-3 was detected by Immunohistochemical staining,the changes in the mRNA levels of IL-1,IL-6,IL-10,TNF-α,IFN-γand MUC2 in colon tissue were detected by quantitative PCR,and the expression level of MUC2 protein in colon tissue was detected with Western blot.Results:Cangfang Decoction effectively improves the disease activity index of DSS-induced UC rats.It also reduces the ulcerative damage of the colon,the inflammatory infiltration and crypt destruction of the colon caused by DSS,and reduces cell apoptosis and mRNA expression levels of IL-1,IL-6,TNF-α,and IFN-γ,enhance the mRNA expression of MUC2 and IL-10 and the protein expression of MUC2.Conclusion:Cangfang Decoction can effectively protect UC induced by DSS in rats.Its mechanism of action may be related to the regulation of inflammatory response and inhibition of apoptosis,providing a molecular biological basis for the UC clinical treatment.