miRNA signatures in diabetic retinopathy and nephropathy: delineating underlying mechanisms

A worldwide failure to achieve glycemic targets has led to complications associated with diabetes mellitus. In addition to genetic and other risk factors, epigenetic factors like DNA methylation, histone modifications, and non-coding RNAs play a significant part in the pathogenesis of complications. Among non-coding RNAs, miRNAs have been explored extensively since they control various biological processes. Their dysregulation has been implicated in various diseases including diabetic complications. Diabetic retinopathy and nephropathy are two common microvascular diabetic complications. Diabetic retinopathy affects the retina of the eye whereas nephropathy damages kidneys on account of prolonged hyperglycemia. This review aims to evaluate the role of miRNAs in diabetic retinopathy and diabetic nephropathy with an emphasis on the dysregulation of various pathways involved. In addition, the role of significant miRNAs as biomarkers for the diagnosis and prognosis of complications has also been discussed. Further, an update on the role of important miRNAs as potential therapeutic modalities has been given.