瑞舒伐他汀钙联合二甲双胍通过调控葡萄糖转运蛋白4表达发挥对糖尿病大鼠肾脏的保护作用研究

Rosuvastatin Calcium with Metformin Improves Kidney Function in a Rat Model of Diabetes by Regulating the Expression of Glucose Transporter 4

背景瑞舒伐他汀钙联合二甲双胍对糖尿病肾损伤具有保护作用,然而其机制尚不十分明确。目的探讨瑞舒伐他汀钙联合二甲双胍在链脲佐菌素(STZ)诱导的2型糖尿病(T2DM)大鼠肾损伤中的保护作用及机制。方法于2021年7—10月将40只清洁级Wistar大鼠随机分为对照组(C组)、二甲双胍组(M组)、二甲双胍+瑞舒伐他汀钙低剂量组(M+RL组)和二甲双胍+瑞舒伐他汀钙高剂量组(M+RH组),每组各10只。M组、M+RL组、M+RH组大鼠腹腔注射STZ,建立T2DM模型。各组药物灌胃:C组:10 mg·kg^(-1)·d^(-1)0.9%氯化钠溶液;M组:二甲双胍(200 mg·kg^(-1)·d^(-1));M+RL组:二甲双胍(200 mg·kg^(-1)·d^(-1))混悬液+瑞舒伐他汀钙(0.42 mg·kg^(-1)·d^(-1));M+RH组:二甲双胍(200 mg·kg^(-1)·d^(-1))混悬液+瑞舒伐他汀钙(0.83 mg·kg^(-1)·d^(-1))。干预6周后处死大鼠,并留取血液及肾脏组织标本。以苏木素-伊红(HE)染色、高碘酸-无色品红(PAS)染色、Masson染色观察各组大鼠肾组织损伤程度;以实时荧光定量聚合酶链式反应(PCR)检测各组大鼠肾脏组织葡萄糖转运蛋白4(GLUT4)mRNA的表达情况;以Western-blotting法检测各组大鼠肾脏组织GLUT4蛋白的表达情况。结果与C组相比,M组、M+RL组、M+RH组大鼠肾小球结构均出现明显损伤,伴有炎性细胞浸润及间质纤维化。M组、M+RL组、M+RH组大鼠肾脏组织GLUT4 mRNA表达水平均低于C组,M组、M+RL组大鼠肾脏组织GLUT4蛋白表达水平均低于C组,M+RL组、M+RH组大鼠肾脏组织GLUT4 mRNA、GLUT4蛋白表达水平均高于M组,M+RH组大鼠肾脏组织GLUT4 mRNA、GLUT4蛋白表达水平高于M+RL组(P<0.05)。结论瑞舒伐他汀钙联合二甲双胍可减轻T2DM大鼠肾小球及肾小管炎性细胞浸润,缓解肾小球基底膜增厚、肾小管空泡变性及肾间质纤维化进程,增加GLUT4 mRNA与GLUT4蛋白表达,且高剂量瑞舒伐他汀钙效果优于低剂量瑞舒伐他汀钙。提示瑞舒伐他汀钙联合二甲双胍可能通过调控GLUT4 mRNA与蛋白的表达,实现对T2DM大鼠肾脏的保护作用,其肾脏保护作用可随瑞舒伐他汀钙剂量增加而增强。

Background Rosuvastatin calcium with metformin improves diabetic renal injury,but the mechanism is not yet fully understood.Objective To explore the mechanism of action of rosuvastatin calcium with metformin improving renal injury in a rat model of streptozotocin(STZ)-induced type 2 diabetes mellitus(T2DM).Methods Forty clean grade Wistar rats were equally randomized into a control group(group C),a metformin group(group M),a metformin+low-dose rosuvastatin calcium group(group M+RL),and a metformin+high-dose rosuvastatin calcium group(group M+RH)from July to October 2021.T2DM model was established for three groups(except for group C)using intraperitoneal injection of STZ.Then drug was administered by intragastric administration to the groups as follows:equal amount of 0.9%sodium chloride solution for group C,metformin(200 mg·kg^(-1)·d^(-1))for group M,metformin(200 mg·kg^(-1)·d^(-1))suspension+rosuvastatin calcium(0.42 mg·kg^(-1)·d^(-1))for group M+RL,and metformin(200 mg·kg^(-1)·d^(-1))suspension+rosuvastatin calcium(0.83 mg·kg^(-1)·d^(-1))for group M+RH.Rats were sacrificed after 6 weeks of intervention,while their blood and kidney tissues were collected.The extent of injury of kidney tissues was observed under light microscope after being stained with H&E,and was analyzed using Image-Pro Plus 6.0 after being stained with periodic-acid schiff,and Masson’s trichrome,respectively.The expression of glucose transporter 4(GLUT4)mRNA in the renal tissue was measured by real-time polymerase chain reaction(PCR),and the protein levels of GLUT4 were detected by Western-blotting.Results Compared with group C,the glomerulus of rats in other three groups showed significant structural damage,accompanied by inflammatory cell infiltration and interstitial fibrosis.Moreover,mRNA expression levels of GLUT4 in these groups were significantly lowered(P<0.05).Furthermore,the protein levels of GLUT4 in groups M and M+RL were lowered notably(P<0.05).The mRNA and protein expression levels of GLUT4 in group M+RL or M+RH were higher than those of group M(P<0.05).In addition,the mRNA and protein expression levels of GLUT4 in M+RH group were higher than those in M+RL group(P<0.05).Conclusion Rosuvastatin calcium with metformin could reduce inflammatory cell infiltration in glomerular and tubular,alleviate glomerular basement membrane thickening and tubular vacuolar degeneration,delay the interstitial fibrosis development,and increase GLUT4 mRNA and GLUT4 protein expression in STZ-induced T2DM rats.Moreover,higher dose of rosuvastatin calcium showed better effect.Our study indicated that rosuvastatin calcium combined with metformin may achieve a renoprotective effect by regulating the expression of GLUT4 mRNA and protein in T2DM rats,and this effect may be enhanced with the increase in the dose of rosuvastatin calcium.