microRNA-206对糖尿病肾病大鼠肾损伤的影响

Effects of microRNA-206 on renal injury in diabetic nephropathy rats

目的探讨微小RNA-206(microRNA-206)对糖尿病肾病(DN)大鼠肾损伤的作用,及其可能机制。方法用高脂饲料+腹腔注射链脲佐菌素建立DN大鼠模型。将造模成功的DN大鼠随机分为模型组、microRNA-206沉默组和microRNA-206过表达组,每组15只;另取15只正常大鼠设为空白组。microRNA-206沉默组大鼠尾静脉注射30 mg·kg^(-1)antagomicroRNA-206;microRNA-206过表达组大鼠尾静脉注射30 mg·kg^(-1)agomicroRNA-206;模型组和空白组大鼠均尾静脉注射等量的0.9%NaCl。4组大鼠每周给药1次,连续给药8周。用全自动生化分析仪检测血清肌酸酐(SCr)和24 h尿蛋白量(24 h UAER),用实时荧光定量聚合酶链反应法检测肾组织中microRNA-206的表达水平,用蛋白质印迹法检测肾组织中胰岛素样生长因子1(IGF-1)和酪氨酸激酶/信号转导与转录激活因子(JAK/STAT)信号通路相关蛋白的表达水平。结果microRNA-206过表达组、microRNA-206沉默组、模型组和空白组的血清SCr分别为(43.72±4.49),(91.24±10.06),(86.71±9.37)和(31.18±4.28)μmol·L^(-1),24 h UAER分别为(25.83±2.36),(39.61±4.42),(34.49±3.53)和(15.58±1.47)mg,microRNA-206表达量分别为0.65±0.07,0.28±0.03,0.43±0.04和1.00±0.00,IGF-1蛋白相对表达水平分别为0.27±0.03,0.44±0.04,0.35±0.04和0.19±0.02,p-STAT1/STAT1比值分别为0.53±0.05,1.22±0.12,0.75±0.08和0.36±0.04,p-JAK2/JAK2比值分别为0.23±0.02,0.68±0.07,0.35±0.04和0.12±0.01。microRNA-206沉默组和microRNA-206过表达组的上述指标与模型组比较,差异均有统计学意义(均P<0.05),microRNA-206过表达组的上述指标与microRNA-206沉默组比较,差异均有统计学意义(均P<0.05)。结论microRNA-206可能通过调控IGF-1表达和介导JAK/STAT信号通路减轻DN大鼠肾损伤。

Objective To investigate the effects and possible mechanism of microRNA-206 on renal injury in diabetic nephropathy(DN)rats.Methods The DN rat model was established by high fat diet and intraperitoneal injection of streptozocin.The successful DN rats were randomly divided into model,microRNA-206 silence and microRNA-206 overexpression groups,15 cases per group.The blank group was composed of 15 normal rats.Rats in microRNA-206 silence group were injected with 30 mg·kg^(-1)antagomicroRNA-206 through caudal vein.Rats in microRNA-206 overexpression group were injected with 30mg·kg^(-1)agromicroRNA-206 through caudal vein.Model and blank groups were injected with the same amount of0.9%NaCl through the caudal vein.Four groups were treated for 8 weeks once a week.The serum creatinine(SCr)and 24-hour urinary protein quantity(24h UAER)were measured by automatic biochemical analyzer.The expression of microRNA-206 in renal tissue was detected by real time fluorescence quantitative polymerase chain reaction.The expressions of insulin-like growth factor 1(IGF-1),Janus kinase/signal transducer and activator of transcription(JAK/STAT)signaling pathway related preteins in renel tissue were detected by Western blot.Results The levels of SCr in microRNA-206 overexpression,microRNA-206 silence,model and blank groups were(43.72±4.49),(91.24±10.06),(86.71±9.37)and(31.18±4.28)μmol·L^(-1);the levels of 24 h UAER were(25.83±2.36),(39.61±4.42),(34.49±3.53)and(15.58±1.47)mg;the expressions of microRNA-206were 0.65±0.07,0.28±0.03,0.43±0.04 and 1.00±0.00;the expressions of IGF-1 protein were 0.27±0.03,0.44±0.04,0.35±0.04 and 0.19±0.02;the ratios of p-STAT1/STAT1 were 0.53±0.05,1.22±0.12,0.75±0.08 and 0.36±0.04;the ratios of p-JAK2/JAK2 were 0.23±0.02,0.68±0.07,0.35±0.04 and 0.12±0.01.The above indexes of microRNA-206 silence group and microRNA-206 overexpression group were significantly different from those of model group(all P<0.05);the above indexes of microRNA-206 overexpression group were significantly different from those of microRNA-206 silence group(all P<0.05).Conclusion MicroRNA-206 may reduce renal injury in DN rats by regulating IGF-1 expression and mediating JAK/STAT signaling pathway.