通络方剂对1型糖尿病大鼠肾功能及肾脏CTGF、RAGE、p-ERK1/2表达的影响

目的观察通络方剂对链脲佐菌素(STZ)诱导的1型糖尿病大鼠肾组织CTGF、RAGE、p-ERK1/2表达的影响,并探讨其可能的肾脏保护机制。方法健康SD大鼠随机分为正常组(n=10)和造模组(n=50)。造模组大鼠给予单次腹腔注射STZ 60 mg/kg,造模成功后随机分为5组:糖尿病非治疗组，通络方剂低、中、高剂量组，氯沙坦组(n=10)。适应性饲养1周后,按分组不同每天分别给予不同处理因素,持续12周后处死,称体质量,测血肌酐、尿素氮,留24 h尿检测尿肌酐、尿蛋白、尿微量白蛋白,取左肾称质量,Real-time PCR法检测右肾组织中CTGF mRNA、RAGE mRNA的表达,Western印迹法检测右肾组织CTGF、RAGE、p-ERK1/2、Total-ERK1/2蛋白的表达。结果通络方剂中、高剂量组较糖尿病非治疗组能明显降低糖尿病大鼠血尿素氮、24 h尿蛋白、尿微量白蛋白、肌酐清除率,改善肾功能,降低RAGE mRNA、CTGF mRNA的表达,减少RAGE、CTGF、p-ERK1/2蛋白表达(P<0.05)。结论通络方剂可能通过抑制RAGE-ERK1/2-CTGF信号转导通路发挥对1型糖尿病大鼠的肾脏保护作用。

Effects of Tongluo recipe on renal function and renal expression of CTGF, RAGE, and p-ERK1/2 in rat model of type 1 diabetes mellitus

ObjectiveTo observe the effects of Tongluo recipe on the renal expression of connective tissue growth factor(CTGF), advanced glycation end products receptor(RAGE) and phosphorylated extracellular signal regulated kinase(p-ERK1/2) in streptozotocin-induced rat model of type 1 diabetes mellitus, and to explore the mechanism of its renoprotective effect. MethodsAdult male Sprague-Dawley rats, weighing 180-220 g, were randomly divided into 2 groups: control group (A, n=10) and model group (n=50). Rat diabetic model was induced by intraperitoneal injection of streptozotocin (60 mg/kg body weight), and the model rats were randomly subdivided into B group (diabetic control, n=10),C group(diabetic rats treated with low dose of Tongluo recipe,0.5 g·kg-1·d-1, n=10), D group (diabetic rats treated with medium dose of Tongluo recipe, 1.0 g·kg-1·d-1, n=10), E group (diabetic rats treated with high dose of Tongluo recipe, 2.0 g·kg-1·d-1, n=10), and F group (diabetic rats treated with losartan, 30 g·kg-1·d-1, n=10). At the end of the 12th week the rats were sacrificed and were weighed; the urea nitrogen (BUN) in blood, serum creatinine (Scr), 24 h albumin excretion rate(UPRO24), microalbuminuria(MAU) and creatinine in urine(Ucr) were analyzed by bio-chemical methods. The left kidneys were weighed and the right kidneys were subjected to real-time PCR analysis for the expression of CTGF and RAGE mRNA. Western blotting analysis was used to examine the expression of CTGF, RAGE, p-ERK1/2, and total-ERK1/2 protein expression. ResultsThe creatinine clearance rate, urea nitrogen, 24 h albumin excretion rate, and microalbuminuria in group D and E were significantly lower than those of group B. And the renal functions of rats in group D and E were improved and the expression of RAGE and CTGF mRNA and protein and p-ERK1/2 protein expression was significantly decreased (P<0.05). ConclusionTongluo recipe may exert its renoprotective effect through inhibiting RAGE-ERK1/2-CTGF signal pathway.