Abstract
Background and Aim: Diabetes mellitus (DM) is a chronic disorder with diabetic retinopathy (DR) as one of its main microvascular outcomes, being a prime cause of vision loss. Dysregulation of microRNAs (miRNAs) has been associated with some diabetic microvascular complications such as diabetic retinopathy. This hypothesised changes in the serum of miR-93 and miR-152 in diabetes and diabetic retinopathy.Methods: The study cohort consisted of 80 healthy volunteers, 80 type 2 diabetic patients, and 80 diabetic retinopathy patients, of whom 40 had proliferative (PDR) and 40 non-proliferative retinopathy (NPDR). Serum fasting and 2-hour postprandial glucose (2hPP), glycated haemoglobin (HbA1c), fasting insulin, and HOMA-IR were evaluated by routine methods, miR-93 and miR-152 expression by quantitative real-time PCR.Results: FBG, 2hPP, fasting insulin, HOMA-IR, and miR-152 showed an increasing trend across groups while miR-93 showed a decreasing trend (all p < 0.001). Binary logistic regression analysis for prediction of DR found that the most significant were miR-152 (OR 1.37, 95% CI: 1.18-1.58, <0.001), BMI (1.13, [1.07-1.31], p = 0.004), duration of disease (1.29 [1.04-1.6] p = 0.018), and miR-152 (0.01, [0.0-0.47] p = 0.019). The most significant predictors of PDR were miR-152 (OR = 1.47, 95% CI: 1.12-1.92, p = 0.005), HOMA-IR (2.66 [1.30-5.45] p = 0.007), and miR-93 (0.25 [0.07-0.86] p = 0.028).Conclusion: MiR-93 and miR-152 can differentiate patients with diabetes and those with DR. Both miRNAs might be potential biomarkers for diabetes and diabetic retinopathy, and specifically for proliferative diabetic retinopathy.