Serum miR-21 and miR-192 levels in type 2 diabetes: Association with albuminuria and renal function

Abstract

Background and aims: Albuminuria is a widely used clinical marker for diabetic nephropathy (DN); however, its limited sensitivity and specificity in detecting early renal alterations highlight the need for additional indicators. MicroRNAs (miRNAs) are emerging as molecular regulators involved in the pathogenesis of DN and may provide insight into early renal involvement in type 2 diabetes mellitus (T2DM). This study aimed to evaluate the serum expression levels of miR-21 and miR-192 in normo- and microalbuminuric patients with T2DM, and explore their associations with metabolic and renal parameters.

Methods: This case-control study included 104 individuals, including 60 patients with T2DM and 44 age- and sex-matched healthy controls. Individuals with diabetes were further classified into 30 normoalbuminuric and 30 microalbuminuric individuals based on the urinary albumin-to-creatinine ratio. Serum levels of miR-21 and miR-192 were quantified using real-time quantitative reverse transcription PCR.

Results: Both miR-21 and miR-192 were significantly upregulated in Patients with T2DM vs healthy controls. Notably, miR-21 expression exhibited a stepwise increase from normo- to microalbuminuria and showed strong correlations with metabolic and renal parameters, including HbA1c, ACR, and lipid profile. In ROC analysis, miR-21 demonstrated better discriminative ability between study groups vs miR-192.

Conclusion: Serum miR-21 may reflect early renal involvement in patients with T2DM. Its progressive increase with albuminuria and strong associations with clinical parameters suggest potential value as a supportive molecular indicator in the early evaluation of diabetic nephropathy. Further prospective studies are needed to validate its clinical applicability.

Keywords: Albuminuria; Diabetes tipo 2; Diabetic nephropathy; Nefropatía diabética; Type 2 diabetes; miR-192; miR-21.