厄贝沙坦对早期糖尿病肾病大鼠足细胞损伤及整合素连接激酶的影响

目的: 研究血管紧张素Ⅱ受体拮抗剂厄贝沙坦(Irb)对早期糖尿病肾病大鼠足细胞损伤及整合素连接激酶(ILK)的影响。方法: 将注射链脲佐菌素(STZ)的自发性高血压大鼠(SHR)分为糖尿病肾病组(DN,n=8)和糖尿病厄贝沙坦治疗组(DN+Irb,n=9),与SHR遗传背景相同周龄和体重相当的非高血压Wistar-Kyoto大鼠作为正常对照(control,n=11)。观察生化指标变化和病理改变情况,以及Irb对糖尿病肾病大鼠足细胞损伤和ILK的影响。结果: 与对照组相比,DN组大鼠表现为高血糖、高血压、高血脂、胰岛素抵抗和蛋白尿;病理上出现系膜基质增生,足细胞数目减少和足细胞损伤;ILK mRNA和蛋白表达水平明显上调。Irb治疗显著降低血压和蛋白尿,抑制足细胞数目减少,减轻足细胞损伤,下调ILK的表达。结论: 糖尿病大鼠早期肾脏足细胞损伤和ILK表达增加,Irb可能通过下调ILK表达而发挥足细胞保护作用。

Effects of irbesartan on expression of integrin-linked kinase and podocyte injury in rats with early diabetic nephropathy

AIM: To determine the influence of irbesartan (Irb) on the podocyte injury and of integrin-linked kinase (ILK) expression in early experimental diabetic nephropathy (DN).METHODS: The hyperglycemic DN rat model was induced by intraperitoneal injection of streptozotocin (STZ,35 mg/kg) in spontaneously hypertensive rats (SHR).The diabetic SHR were randomly divided into 2 groups: DN SHR (DN,n=8) and DN SHR treated with irbesartan (50 mg/kg per day by gavage for 8 weeks,DN+Irb,n=9).Non-diabetic normotensive Wistar-Kyoto rats (WKY,the animals of normal blood pressure have the same genetic background with SHR) were used as control (control,n=11).The biochemical parameters and pathological changes were analyzed.Moreover,the influence of irbesartan on the expression of ILK and podocyte injury in SHR with DN was examined.RESULTS: Compared with control,DN SHR were associated with hyperglycaemia,hypertension,hyperlipidaemia,insulin resistance and albuminuria,which were similar to those of human T2DN.In addition,these DN SHR showed expansion of mesangial matrix,loss of podocyte and podocyte injury.Importantly,the expression of ILK in DN SHR was upregulated as compared to control.Treatment with irbesartan significantly decreased this overexpression of ILK,along with a decrease in albuminuria,reduction of blood pressure,prevention of podocyte injury,inhibition of mesangial matrix expansion and restoration of podocyte numbers.CONCLUSION: ILK is involved in the podocyte injury in DN.Irbesartan downregulates the expression of ILK and decreases podocyte injury.