Clinical significance of miR-126 as marker in the diagnosis of type 2 diabetic kidney disease

Objective To explore the clinical significance of miR-126 as a marker in the diagnosis of type 2 diabetic kidney disease (T2DKD).Methods From Jan. 2008 to Dec. 2015, 80 patients with T2DKD in our hospital were selected. The patients were divided into T2DKD group (n=40) and diabetic control group (T2DM group, n=40) according to the level of urinary protein. According to the patient's urine protein content T2DKD group was divided into microalbuminuria subgroup (n=22) and macroalbuminuria group (n=18). Forty healthy volunteers were selected as healthy control group (n=40). The estimated glomerular filtration rate (eGFR), and levels of FBG, HbA1c, HDL-C, TC, TG, LDL-C, triacylglycerol (TG), urinary protein, serum creatinine, plasma D-two dimmer were determined. The miR-126 level was detected by real-time fluorescence quantitative PCR. The correlation between miR-126 and important clinical indicators was analyzed. Univariate and multivariate linear regression analysis was used to determine the risk factors of T2DKD patients with microalbuminuria and macroalbuminuria.Results Among T2DM group, T2DKD group and healthy control group, there was no significant difference in age and sex (P>0.05). As compared with the healthy control group, There was significant difference in the levels of FBG, HbA1c, serum creatinine and the relative expression of miR-126 between healthy control group and T2DM group (P<0.05). Between T2DKD group and healthy control group, there was significant difference in the BMI, FBG, HbA1c, the average value of blood pressure, TC, LDL-C, TG, urinary protein, albumin/creatinine, serum creatinine, eGFR, and the relative expression of miR-126. Between T2DM group and T2DKD group, there was significant difference in the average blood pressure, TG, urinary protein, albumin/creatinine, serum creatinine, eGFR, the relative expression of miR-126 (P<0.05). MiR-126 was negatively correlated with TC and LDL-C (P<0.05), and positively correlated with HDL-C (P<0.05). Cox proportional hazard regression model revealed that the risk factors of T2DKD patients included FBG > 4 mmol/L, HbA1c > 5%, LDL-C > 2 mmol/L, and miR-126 relative expression < 25 (P<0.05). The risk factors of T2DKD patients with microalbuminuria and macroalbuminuriawere included FBG>8 mmol/L, HbA1c >9%, LDL-C >4 mmol/L, miR-126 relative expression <4, and TG >2 mmol/L (P<0.05).Conclusions Low relative expression of miR-126 in blood circulation is a risk factor for T2DKD patients. In the clinical diagnosis of T2DKD, the levels of miR-126 in the blood circulation can be used as a marker or therapeutic target.