Evaluation of serum MicroRNA 21, MicroRNA 192 and serum TGFβ1 in type 2 diabetes mellitus patients and their relation to diabetic nephropathy

Diabetic nephropathy (DN) is a frequent and long-lasting microvascular consequence that has an established connection with diabetes. It serves as the primary etiological agent of end-stage renal disease, a critical renal disorder that develops on a worldwide level. The molecular pathophysiology of DN is multifactorial, such as transforming growth factor-beta [TGF-β] which affects the expression of miRNAs such as miRNA-21 and miRNA-192 during renal fibrosis. However, to date, the clinical application is inadequate due to discrepancies observed in the published data. This cross-sectional investigation aimed to assess the correlation between serum TGF-β1, miRNA-21 and 192, and glycemic control, metabolic abnormalities, and renal function in patients with type II diabetes. Based on the albumin/creatinine ratio (ACR), fifty subjects with type II diabetes were divided into three categories: Group I consisted of individuals with normoalbuminuria (n = 16), Group II of microalbuminuria (n = 16), and Group III of overt proteinuria (n = 18). All participants were subjected to the estimation of mature miRNA-21 and miRNA-192 by TaqMan two-step stem loop qRT-PCR and serum TGFβ1 level by ELISA. There was an upregulation in miRNA-21 expression in the 3 different groups of patients (p value = 0.043). The serum fold change (FC) of miRNA-21 showed significantly greater median values in patients with overt proteinuria compared to those with normoalbuminuria (5.57 FC versus 1.11 FC, p = 0.017). A positive correlation (r = 0.343) (p = 0.013) was observed between the ACR and the median levels of miRNA-21, which was statistically significant. No statistically significant distinctions were detected in the concentrations of serum TGF-β1 or miRNA-192 among the three patient groups (p values of 0.234 and 0.225, respectively). The findings of the present research implied that miRNA-21 might function as an early indicator of renal pathology associated with diabetes mellitus (DM).