双峰驼奶对2型糖尿病大鼠肾组织结构及其细胞凋亡的影响

Effects of bactrian camel milk on histology and cell apoptosis of kidney in type 2 diabetes mellitus rats

观察双峰驼奶对2型糖尿病大鼠肾组织结构及其细胞凋亡的影响,为临床预防和治疗糖尿病及其并发症提供理论参考。通过链脲佐菌素(streptozotocin,STZ)结合高糖高脂饮食诱导构建2型糖尿病(type 2diabetes mellitus,T2DM)大鼠模型,糖尿病大鼠随机分为糖尿病模型组(diabetes model control,DMC)、低剂量骆驼奶组(2ml/d)(low camel milk,LCM)、高剂量骆驼奶组(5ml/d)(high camel milk,HCM)和盐酸二甲双胍组(200mg/kg)(metformin hydrochloride,MTH),每组12只,另设正常对照组(control group,C)。建模成功后,试验组处理4周后检测大鼠空腹血糖(FPG)浓度变化;采用苏木精-伊红(HE)染色方法检查肾脏组织的病理变化;采用荧光定量Real time-PCR法检测Bax(Bcl2-associated X protein,Bax)、Bcl-2(B cell lymphoma/lewkmia-2,Bcl-2)、细胞凋亡蛋白酶3(cysteinyl aspartate specific proteinase 3,Caspase 3)和核转录因子(nuclear factor-kappa B,NF-κB)mRNA的表达丰度;采用免疫组织化学染色法和免疫印迹法观察肾脏组织凋亡相关蛋白Bax和Bcl-2的表达变化。结果显示,与DMC组相比,LCM、HCM、MTH组大鼠FPG浓度均显著下降(P<0.01),LCM组大鼠胰岛素敏感性指数(ISI)显著升高(P<0.01);HE染色显示DMC组肾小球体积增大,囊腔变小,肾小球内出血严重,而LCM、HCM、MTH组肾小球体积、囊腔间隙较正常,肾小球出血明显减少;Bax mRNA和NF-κB mRNA在DMC组中表达量最高,Bcl-2mRNA和Caspase 3mRNA分别在LCM组和HCM组有较高的表达量;与DMC组相比,LCM、HCM、MTH组大鼠肾脏细胞Bax蛋白表达减低,Bcl-2蛋白表达升高。结果表明,双峰驼奶能显著降低糖尿病大鼠肾脏损伤,抑制其细胞凋亡,对糖尿病及其并发症的治疗发挥有效作用。

To investigate the protective effects of bactrian camel milk on histology and cell apoptosis of kidney in type 2diabetes mellitus（T2DM）rats.T2 DM rat model was established by feeding high-calorie forage and intraperitoneal injection of streptozotocin.Sixty adult male rats with similar month of age and body condition were randomly divided into the diabetes model group（DMC）and three treatment groups,including low concentration camel milk（LCM）group,high concentration camel milk（HCM）group and metformin hydrochloride（MTH）group,12 in each group.12 healthy rats were taken as control.After 4weeks treatment,the blood were collected for determining fasting plasma glucose（FPG）concentration.Pathological changes of kidney tissue were observed by HE staining;the expressions of Bax（Bcl2-associated X protein,Bax）,Bcl-2（B cell lymphoma/lewkmia-2,Bcl-2）,Caspase 3（cysteinyl aspartate specific proteinase 3,Caspase 3）and NF-κB（nuclear factor-kappa B）mRNA were detected by RT-qPCR;the expressions of Bax and Bcl-2protein were detected by immunohistochemical and western blotting methods.Compared with DMC group,FPG in LCM,HCM and MTH group was significantly decreased（P0.01）,insulin sensitivity index（ISI）in LCM group was significantly increased（P0.01）.HE staining showed that larger renal glomerulus,smaller renal capsule and renal glomerulus bleeding in DMC group,while the structure of kidney tissue was alleviated in LCM,HCM and MTH group.The expressions of Bax mRNA and NF-κB mRNA were the highest in DMC group,Bcl-2mRNA and Caspase 3mRNA were the highest in LCM group and HCM group,respectively.To compare with DMC group,the expression of Bax protein was decreased in LCM,HCM and MTH group,on the contrary,Bcl-2was increased.The results reveal that bactrian camel milk can reduce kidney injury and suppress cell apoptosis of T2 DM rats,which provides an effective treatment for diabetes mellitus.