尿胞外体亮氨酸氨基肽酶及二肽基肽酶在糖尿病肾病中的变化

摘要

AIM: To investigate the changes of urinary exosomal enzymes and the correlation with diabetic nephropathy.METHODS: Thirty - four healthy volunteers and 127 patients of type 2 diabetes mellitus ( T2DM ) were included in the study.The healthy volunteers served as control.The patients with T2DM were divided into 3 groups based on their 24 h urinary albumin/creatinine ratio ( UACR ): 50 patients with microalbuminuria in early DN group ( DN1 ), 34 patients with macroalbuminuria in overt DN group ( DN2 ) and 43 patients without albuminuria in DM group.The levels of urine exosomal leucine aminopeptidase( exosome - LAP ) and exosomal dipeptidyl peptidase 4( exosome - DPP4 ) were determined by enzyme - linked immunosorbent assay ( ELISA ).The following methods were used to determine the biochemical parameters: liquid chromatography for glycated hemoglobin ( HbA1c ), chemical modification method for cholesterol ( CH ), Jaffe - kinetic assay for creatinine ( CR ) and urease - GLDH method for blood urea nitrogen ( BUN ).Multiple stepwise linear regressions were used to analyze the relationship of exosome - LAP or exosome - DPP4 with HbA1c, CH, UACR, CR and BUN.RESULTS: The levels of exosome - LAP and exosome - DPP4 in DM, DN1 and DN2 groups were significantly higher than those in control group ( P ＜0.01 ).The exosome - LAP in DN2 group was significantly higher than that in DM group.Correlation analysis showed that the levels of urinary exosome - LAP and exosome - DPP4 were positively correlated with HbA1c, CH, UACR, CR and BUN.Multiple stepwise linear regression analysis showed that CH and UACR were independent determinants for exosome - LAP ( P ＜0.01 ), and UACR and HbAlc were independent determinants for exosome - DPP4 ( P ＜0.01 ).CONCLUSION: Urine exosome - LAP and exosome - DPP4 are correlated with the severity of diabetic nephropathy.These parameters may serve as clinical markers for the diagnosis and prognosis evaluation of diabetic nephropathy.%目的:探讨 2 型糖尿病患者尿液胞外体的亮氨酸氨基肽酶(exosome - LAP)及二肽基肽酶4(exosome - DPP4)的水平变化在糖尿病肾病发展过程中的意义.方法:选取 127 例 2 型糖尿病患者,根据 24 h 尿白蛋白肌酐比(UACR)分为糖尿病正常白蛋白尿组(DM,43 例)、微量白蛋白尿组(DN1,50 例)和大量白蛋白尿组(DN2,34 例).另选健康对照组 34 例.采用特异性的单克隆抗体提纯胞外体,酶联免疫吸附法(ELISA)检测尿液胞外体的 exosome - LAP 和exosome - DPP4.同时检测糖化血江蛋白(HbA1c)、血胆固醇(CH)、肌酐(CR)、尿素氮(BUN).应用多元逐步回归方法分析 DPP4 及 LAP 与 HbA1c、CH、UACR、CR、BUN 相关性.结果:DM、DN1、DN2 组 exosome - LAP和exosome - DPP4 水平均显著高于正常组(均P<0.01);与 DM 组比较,DN2 组 exosome - LAP水平显著升高(P<0.01).尿 exosome - LAP、exosome - DPP4 与 HbA1c、CH、UACR、CR、BUN 显著相关.逐步多元回归分析显示,CH、UACR 是 exosome - LAP 的独立危险因素(均P<0.01);UACR、HbA1c 是 exosome - DPP4 的独立危险因素(均P<0.01).结论:Exosome - LAP和exosome - DPP4 水平与糖尿病肾病严重程度密切相关,以上指标对于糖尿病肾病的诊断及预后估计具有一定临床价值.