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

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

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STZ60mg/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24h尿检测尿肌酐、尿蛋白、尿微量白蛋白,取左肾称质量,Real-timePCR法检测右肾组织中CTGFmRNA、RAGEmRNA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、24h尿蛋白、尿微量白蛋白、肌酐清除率,改善肾功能,降低RAGEmRNA、CTGFmRNA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。

Objective To observe the effects of Tongluorecipe 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 1diabetes mellitus,and to explore the mechanism of its renoprotective effect.Methods Adult male Sprague-Dawley rats,weighing 180-220g,were randomly divided into 2groups：control group （A,n=10）and model group（n=50）.Rat diabetic model was induced by intraperitoneal injection of streptozotocin（60mg/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,0.5g·kg-1·d-1,n=10）,D group（diabetic rats treated with medium dose of Tongluorecipe,1.0g·kg-1·d-1,n=10）,E group（diabetic rats treated with high dose of Tongluorecipe,2.0g·kg-1· d-1,n=10）,and F group（diabetic rats treated with losartan,30g·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）,24halbumin 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-ERK1/2protein expression.Results The creatinine clearance rate,urea nitrogen,24halbumin 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-ERK1/2protein expression was significantly decreased（P〈0.05）.Conclusion Tongluo recipe may exert its renoprotective effect through inhibiting RAGE-ERK1/2-CTGF signal pathway.