Urinary and Plasma miRNAs in the Early Detection of Acute Kidney Injury and Their Possible Role as Therapeutic Targets.

Acute Kidney Injury (AKI) is a severe clinical condition featured by a rapid decrease in kidney function in a short period of time. AKI, which is often secondary to sepsis, ischemia-reperfusion and drug toxicity, is associated to high morbidity and mortality. Moreover, it contributes to the development of chronic kidney disease (CKD), due to maladaptive or incomplete repair mechanisms, resulting in renal fibrosis. Small non-coding RNA has recently emerged as a novel biomarker for the early detection and treatment of AKI. In particular, microRNAs (miRNAs) are non-coding RNA molecules of 21-25 nucleotides regulating the expression of protein-coding genes through sequence-specific recognition. Due to their high stability in biological fluids, such as urine and plasma, they can be reliably analyzed and quantified, and for this reason they can be considered potential diagnostic and therapeutic biomarkers. Specifically, miRNAs have been demonstrated to predict AKI before the increase in creatinine levels, thus improving the management of this syndrome. In this review, we provide a comprehensive overview of the role of urinary and plasma miRNAs in the early detection and treatment of AKI.