黄连温胆汤对2型糖尿病模型大鼠细胞因子及TLR4、NF-κB变化的影响

Effects of Huanglian Wendan Decoction on Cytokines,TLR4 and NF-κB in Rats with T2DM

目的:研究黄连温胆汤对2型糖尿病模型大鼠细胞因子及Toll样受体4(TLR4)、核因子κB(NF-κB)变化的影响。方法:选择SPF级SD大鼠,先随机分10只为正常对照组,其余大鼠均以高糖高脂乳剂10 mL/kg·d灌胃8 w,并每隔7 d进行血糖的监测,8 w后,以35 mg/kg的链脲佐菌素(STZ)腹腔注射诱导2型糖尿病模型,选取空腹血糖值大于11 mmol/L造模成功的大鼠随机分为五组:模型对照组、二甲双胍0.25 g/kg组和黄连温胆汤3、6、12 g/kg组。各组灌胃相应药物或生理盐水,1次/d,用药4 w后,取材检测。酶联免疫法检测大鼠血清中脂多糖(LPS)、肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)、白细胞介素10(IL-10)的含量;实时荧光定量PCR检测大鼠结肠组织Tlr4、Nf-κb mRNA表达;免疫组化测定大鼠胰腺组织TLR4、NF-κB蛋白的表达。结果:与正常对照组相比,模型对照组大鼠血清中LPS、TNF-α、IL-6含量显著升高,IL-10含量显著下降(P<0.01);结肠组织Tlr4、Nf-κb mRNA表达显著上调(P<0.01);胰腺组织TLR4、NF-κB蛋白表达显著上调(P<0.01)。与模型对照组比较,黄连温胆汤12、6、3 g/kg组和二甲双胍0.25 g/kg组大鼠血清中LPS、TNF-α、IL-6含量明显下降,IL-10含量明显升高(P<0.05或P<0.01);结肠组织Tlr4、Nf-κb mRNA表达显著下调(P<0.01);胰腺组织TLR4、NF-κB蛋白表达明显下调(P<0.05或P<0.01)。结论:黄连温胆汤通过调控LPS/TLR4/NF-κB炎症信号通路,抑制炎症因子,从而改善2型糖尿病胰岛素抵抗。

Objective:To study the effects of Huanglian Wendan Decoction on cytokines,toll-like receptor 4(TLR4)and nuclear factor-κB(NF-κB)in rats with type 2 diabetes mellitus(T2 DM).Methods:From the selected SPF SD rats,10 were classified into the normal control group.The remaining ones were treated with intragastric administration of high-sugar and high-fat emulsion at 10 mL/kg for eight weeks,during which the blood glucose was monitored once every seven days.Eight weeks later,the T2 DM rat model was established by intraperitoneal injection of 35 mg/kg streptozotocin(STZ).Rats with fasting blood-glucose(FBS)greater than 11 mmol/L were considered to be successfully modeled and they were randomly divided into the model group,metformin(0.25 g/kg)group,and low-(3 g/kg),medium-(6 g/kg),and high-dose(12 g/kg)Huanglian Wendan Decoction groups.Following the administration of rats with corresponding drugs or normal saline,once a day,for four weeks,the samples were collected for detection.The contents of serum lipopolysaccharide(LPS),tumor necrosis factorα(TNF-α),interleukin-6(IL-6)and IL-10 were detected by ELISA.The mRNA expression levels of TLR4 and NF-κB in colonic tissue were determined by qRT-PCR,and the protein expression levels of TLR4 and NF-κB in pancreatic tissue by immunohistochemistry.Results:Compared with the normal control group,the model group exhibited significantly elevated serum LPS,TNF-αand IL-6,lowered IL-10(P<0.01),and up-regulated TLR4 and NF-κB mRNA expression in colonic tissue(P<0.01)and TLR4 and NF-κB protein expression in pancreatic tissue(P<0.01).Compared with the model group,Huanglian Wendan Decoction at 12 g/kg,6 g/kg,and 3 g/kg and metformin at 0.25 g/kg all significantly decreased the contents of LPS,TNF-αand IL-6 in rat serum,increased IL-10 content(P<0.05 or P<0.01),down-regulated TLR4 and NF-κB mRNA expression in colonic tissue(P<0.01)and TLR4 and NF-κB protein expression in pancreatic tissue(P<0.05 or P<0.01).Conclusion:Huanglian Wendan Decoction regulates the LPS/TLR4/NF-κB inflammatory pathway and inhibits inflammatory cytokines to improve insulin resistance of T2 DM.