Beclin1在糖尿病肾病模型大鼠肾组织的表达变化研究

The Study on the Beclin1 Expression and Change in Diabetic Rats

目的探讨beclin1在糖尿病肾病(DN)大鼠模型肾组织中的表达及在DN发病机制中的作用。方法通过腹腔注射链脲佐菌素(50 mg/kg)制作DN大鼠动物模型,以造模后72 h血糖≥16 mmol/L,1周后纸片法检测尿蛋白阳性认为DN造模成功。免疫比浊法检测大鼠尿白蛋白(ALb)24 h排泄率以及尿白蛋白与肌酐比值(urinary albumin and urinary creatinine ratio,ACR),免疫组化Envision两步法检测beclin1在DN模型肾组织的表达,透射电镜观察肾组织细胞内自噬囊结构及溶酶体形态。结果①DN大鼠ALb及ACR均较空白对照组增加(P<0.05)。随着造模时间延长,在造模后4周、8周增加更加明显(P均<0.05)。②两组大鼠肾组织扫描电镜偶可见自噬囊泡。③免疫组化显示正常大鼠肾小管细胞见beclin1表达,肾小球未见表达,DN大鼠肾组织表达强于正常大鼠(P<0.05),肾小球可见表达。结论 beclin1可能参与DN发病过程,机制可能与DN过程中细胞程序性死亡发生有关。

Objective To study the expression of beclin1 in renal tissue of diabetic rats,and its role in diabetic nephropathy（DN）.Methods Diabetic rat model was produced by intraperitoneal injection of streptozotocin（50 mg/kg）,it was considered to be diabetic nephropathy that 72 h blood glucose after modeling was higher than 16 mmol/L.The positive urine protein was detected by paper method at the end of 1 week.24 h urine albumin excretion（ALb） and urinary albumin and urinary creatinine ratio（ACR） were examined by immunoturbidimetry,Beclin1 expression was also studied by immunohistochemistry with envision method.The electron microscopy was used to detect the form of autophagic vesicles and lysosome.Results ① Compared with control group,the 24-hour urinary albumin excretion rate and ACR in diabetic rats were significantly higher.② The electron microscopy showed there were autophagic vesicles in renal tissue in both groups;③ Immunohistochemistry showed beclin1 expression in normal rat kidney cells partly,while no expression in glomeruli.The expression of beclin1 in DN renal tissue was stronger than that in normal rats（P0.05）.Conclusion beclin1 may be involved in the pathogenesis of diabetic nephropathy with the mechanism related to the process of programmed cell death.