连术消渴颗粒对2型糖尿病模型大鼠肠道菌群、肠黏膜屏障功能及水通道蛋白的影响

目的:研究连术消渴颗粒对2型糖尿病(T2DM)模型大鼠肠道菌群、肠黏膜屏障功能及水通道蛋白的影响。方法:选取60只SD大鼠,随机分为空白组、模型组、连术消渴颗粒低剂量组、连术消渴颗粒中剂量组、连术消渴颗粒高剂量组及二甲双胍组。模型组、连术消渴颗粒低剂量组、连术消渴颗粒中剂量组、连术消渴颗粒高剂量组及二甲双胍组大鼠采用腹腔注射链脲佐菌素(STZ)制备T2DM模型,成模后连术消渴颗粒低剂量组、连术消渴颗粒中剂量组、连术消渴颗粒高剂量组及二甲双胍组分别给予连术消渴颗粒2.92、5.84、11.68 g/(kg·d)及盐酸二甲双胍片0.17 g/(kg·d)灌胃,空白组及模型组给予相同体积纯净水灌胃,各组大鼠均治疗30 d。检测各组大鼠空腹血清胰岛素(FINS)、空腹血糖(FBG)、胰岛素抵抗指数(HOMA-IR),采用粪便培养检测大肠杆菌、双歧杆菌及乳酸杆菌菌落数的对数值; 采用酶联免疫法检测各组大鼠血清肠黏膜屏障功能指标D-乳酸(D-LA)、连蛋白(Zonulin)及乳脂球表皮生长因子-8(MFG-E8)含量; 采用Western blot法检测各组大鼠结肠组织水通道蛋白4(AQP4)、水通道蛋白8(AQP8)表达。结果:与空白组比较,模型组FINS降低,FBG及HOMA-IR升高(均P<0.05),粪便培养大肠杆菌数量增加,双歧杆菌及乳酸杆菌数量降低,血清D-LA、Zonulin含量升高,MFG-E8含量降低,结肠组织AQP4、AQP8表达降低(均P<0.05)。与模型组比较,连术消渴颗粒低剂量组、连术消渴颗粒中剂量组、连术消渴颗粒高剂量组及二甲双胍组FINS升高,FBG、HOMA-IR降低,粪便培养大肠杆菌数量降低,双歧杆菌及乳酸杆菌数量增加,血清D-LA、Zonulin含量降低,MFG-E8含量升高,结肠组织AQP4、AQP8表达升高(均P<0.05),且呈剂量依赖性。结论:连术消渴颗粒可改善T2DM模型大鼠糖代谢,修复肠黏膜屏障功能,提高结肠水通道蛋白表达,其机制可能与改善肠道菌群有关。

Effect of Lianzhu Xiaoke granule on intestinal flora,intestinal mucosal barrier function and aquaporin in type 2 diabetes model rats

Objective:To investigate the effect of Lianzhu Xiaoke granule on intestinal flora,intestinal mucosal barrier function and aquaporin in type 2 diabetes mellitus(T2DM)model rats.Methods:60 SD rats were randomly divided into blank group,model group,Lianzhu Xiaoke granule low dose group,Lianzhu Xiaoke granule medium dose group,Lianzhu Xiaoke granule high dose group and metformin group.The T2DM model was prepared by intraperitoneal injection of STZ in the model group,the Lianzhu Xiaoke granule low dose group,Lianzhu Xiaoke granule medium dose group,Lianzhu Xiaoke granule high dose group and the metformin group.After modeling,the Lianzhu Xiaoke granule low dose group,Lianzhu Xiaoke granule medium dose group,Lianzhu Xiaoke granule high dose group and metformin group were given Lianzhu Xiaoke granule 2.92,5.84,11.68 g/(kg·d)and metformin acid 0.17 g/(kg·d)respectively by gavage.The blank group and the model group were given pure water,and the rats in each group were treated for 30 d.Fasting insulin(FINS),fasting glucose(FBG)and insulin resistance index(HOMA-IR)of rats in each group were detected.The logarithm values of the bacterial colonies of enterobacter pylori,bifidobacterium and lactobacillus were detected by fecal culture.The contents of d-lactic acid(D-LA),Zonulin and MFG-8(MFG-E8)were measured by enzyme-linked immunity.Western blot method was used to detect the expressions of aquaporin 4(AQP4)and aquaporin 8(AQP8)in colon tissues of rats in each group.Results:Compared with the blank group,FINS were decreased,FBG and HOMA-IR increased in the model group,the number of fecal cultured escherichia coli increased,the number of bifidobacterium and lactobacillus decreased,the content of serum D-LA and zonulin increased,the content of MFG-E8 decreased,and the expression of AQP4 and AQP8 in colon tissue decreased(all P<0.05).Compared with model group,the Lianzhu Xiaoke granule low dose group,Lianzhu Xiaoke granule medium dose group,Lianzhu Xiaoke granule high dose group and metformin group FINS increased,FBG and HOMA-IR reduced,the number of escherichia coli in fecal culture decreased,the number of bifidobacterium and lactobacillus increased,serum D-LA,Zonulin decreased,MFG-E8 content increased,colon tissue AQP4,AQP8 expression increased(all P<0.05)and dose dependent.Conclusion:Lianzhu Xiaoke granule can improve the glucose metabolism,repair the intestinal mucosal barrier function,and increase the expression of colon aquaporin in T2DM model rats,which may be related to the improvement of intestinal flora.