Diagnostic Value Of Serum MiR-21in Diabetic Nephropathy

ObjectiveThe SYBR Green I fluorescent quantitative PCR for detection of serum miR-21expressionlevel,and to evaluate the diagnostic value of serum miR-21as a molecular biomarker in patientswith diabetic nephropathy.METHODS1.25patients with diabetic nephropathy(DN),25patients with type II diabetes and UmAlb＜14.29μg/mL（DMA）,25patients with type II diabetes B and UmAlb＞14.29μg/mL（DMB）,25patients with diabetic nephropathy induced uremia (UM)and25normal control(NC) wereincluded in the study. Total RNA was extracted from serum samples for measurement ofmiR-21levels using real-time fluorescence quantitative PCR;2. The relationship between miR-21levels and clinical parameters of diabetic nephropathypatients was analyzed by Pearson and Spearman rank correlation analysis;3. To establish Logistic regression model and draw ROC curve and to evaluate the diagnosticefficiency of serum miR-21in diabetic nephropathy by using related indexes of clinicaldiagnostic trial.RESULTS1. The relative expression levels of serum miR-21was significantly lower in the DN group thanin the DMA,DMB and NC group, and significantly higher than in the UM group (﹣0.73±0.53vs0.00±0.30,0.52±0.62,﹣0.38±0.31,﹣1.54±0.25;all P＜0.01);2. Serum miR-21levels showed no significant correlation with Sex、Age、Scr、Bun、FGB、HbAlc、UMTP and Ucr,but significant negative correlation with Cysc,UmAlb, UmAlb/Ucr inDN patients（r=﹣0.630,P=0.001;r=﹣0.426,P=0.034;r=﹣0.487,P=0.013); 3. For discriminating DN patients from NC,DMA, DMB,and DMA＋NC,DMB＋NC,DMA＋DMB, the area under the receiver operating characteristic curve (AUC-ROC) for serummiR-21were0.848(95%CI:0.737-0.959),0.896(95%CI:0.812-0.980),0.782(95%CI:0.641-0.922),0.838(95%CI:0.743-0.933),0.796(95%CI：0.675-0.917),0.808(95%CI:0.704-0.911), and thesensitivity and specificity were80.0%and72.0%,72.0%and88.0%,72.0%and84.0%,76.0%and77.0%,76.0%and82.0%,70.0%and86.0%,respectively. For discriminating DN patientsfrom those with DMA＋DMB＋NC, the AUC-ROC was0.845(95%CI：0.752-0.939), andthe sensitivity and specificity were76.0%and77.3%, respectively.CONCLUSIONSerum miR-21expression level of NC group、DMA group、DMB group、DN group and UMgroup showed a significantly statistical difference; Serum miR-21may serve as a moleculardiagnostic marker for diabetic nephropathy.