小檗碱调节Nrf2/HO-1信号通路改善脓毒症肠道损伤

Berberine ameliorates intestinal injury in sepsis by regulating Nrf2/HO-1 pathway

目的探讨小檗碱改善脓毒症大鼠肠道损伤的作用及其机制。方法将40只雄性健康SD大鼠随机分为假手术组,模型组,小檗碱低、中、高剂量(25、50、100 mg·kg^(-1))组,每组8只,灌胃给予对应剂量7 d后采用盲肠结扎穿孔(CLP)法造脓毒症大鼠模型。造模后24 h麻醉取血并留取回肠标本,观察大鼠回肠组织光镜下的病理变化并进行病理评分比较。利用ELISA法检测各组大鼠血清血红素加氧酶-1(HO-1)、二胺氧化酶(DAO)、肠脂肪酸结合蛋白(iFABP)、肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-1β的含量,比色分析法检测大鼠回肠组织中丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性,Western blot法检测回肠组织HO-1、核因子E2相关因子2(Nrf2)及IL-1β蛋白水平。结果与假手术组相比,模型组回肠组织病理学评分显著升高(P<0.01),血清HO-1、IL-1β、IL-6、TNF-α、DAO、iFABP及肠组织MDA含量升高,而肠组织SOD活性降低,Nrf2、HO-1及IL-1β蛋白表达明显升高(P<0.01)。与模型组相比,小檗碱高剂量组回肠组织病理学评分明显降低(P<0.01),血清IL-1β、IL-6、TNF-α、DAO、iFABP及肠组织MDA含量也降低(P<0.05),而血清HO-1含量及肠组织SOD活性升高(P<0.01),Nrf2、HO-1表达上调,IL-1β表达降低(P<0.05)。结论小檗碱能有效改善脓毒症导致的肠损伤,其机制可能与小檗碱上调Nrf2/HO-1表达相关。

AIM To explore the effects of berberine on intestinal injury in sepsis rats and its mechanism.METHODS Forty male healthy SD rats were randomly divided into sham group,model group,berberine low,medium,and high dose(25,50,100 mg·kg^(-1))groups,with 8 rats in each group,and the corresponding dose was given by gavage for 7 d.Sepsis model was prepared by cecum ligation and perforation(CLP).After 24 h of modeling,the rats were anesthetized and the ileum specimens were collected.The pathological changes of the ileum were observed and scored under light microscope.The contents of serum heme oxygenase-1(HO-1),diamine oxidase(DAO),intestinal fatty acid binding protein(iFABP),tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-1βwere detected by ELISA.The content of malondialdehyde(MDA)and the activity of superoxide dismutase(SOD)in ileum were detected by colorimetric analysis.The protein levels of HO-1,nuclear factor E2-related factor 2(Nrf2)and IL-1βin ileum were detected by Western blot.RESULTS Compared with the sham group,ileum histopathological score was significantly increased in the model group(P<0.01),and contents of HO-1,IL-1β,IL-6,TNF-α,DAO,iFABP in serum,and MDA in intestinal tissue were increased,while SOD activity was decreased,and the expressions of Nrf2,HO-1 and IL-1βprotein in the model group were significantly increased(P<0.01).Compared with the model group,the ileum histopathologic score of the berberine high dose group was significantly decreased(P<0.01),the contents of IL-1β,IL-6,TNF-α,DAO,iFABP in serum and MDA in intestinal tissue were also decreased(P<0.05),while the HO-1 content in serum and SOD activity in intestinal tissue were increased(P<0.01),and the protein expressions of Nrf2 and HO-1 in the berberine high dose group were significantly increased,but the IL-1βprotein expression was decreased(P<0.05).CONCLUSION Berberine can effectively improve intestinal damage caused by sepsis,and its mechanism may be related to the up-regulation of Nrf2/HO-1 expression.