Urinary miR-146a is elevated in patients with diabetic nephropathy and correlates with albuminuria
Abstract: Previous studies suggested that miR-146a expression was elevated in kidney biopsy and urine from nephropathy patients or rats. In this study, we investigated the possibility of urinary miR-146a as biomarker for diabetic nephropathy (DN) and its potential mechanism. 68 patients with type 2 diabetes mellitus (T2DM) were enrolled in the study. Urinary miR-146a level was measured by qRT-PCR and compared among 36 non-DN subjects, 20 early DN subjects, and 12 clinical DN subjects. The effect of miR-146a on apoptosis of mouse mesangial cells (mMCs) was also studied by Heochst staining. DN patients showed higher urinary miR-146a level compared with non-DN patients (P<0.05). Urinary miR-146a level was correlated with urinary albumin excretion rate (r=0.951, P<0.01). However, there was no significant correlation between urinary miR-146a level and renal function parameters including serum creatinine, cystatin C, β2-microglobulin, and estimated glomerular filtration rate. Transfecting mMCs with miR-146a mimics inhibited cellular growth and promoted apoptosis and collagen I production. In conclusion, miR-146a was involved in development of DN. Urinary miR-146a may be a potential biomarker for DN.