The extracellular miRNA fingerprint of kidney disease: a narrative review

Abstract

Background and Objective: MicroRNAs (miRNAs) are small non-coding RNA molecules that post-transcriptionally regulate gene expression by binding to their target mRNAs. In kidney, miRNAs have been implicated the development of several diseases, including chronic and acute kidney disease, diabetic nephropathy (DN), hypertensive nephropathy, kidney immune diseases and polycystic kidney disease (PKD), among others. The association of miRNA levels in bodily fluids with disease progression, suggests their role as mediators of renal pathophysiology and their use as biomarkers. This review discusses current knowledge of miRNA function in kidney diseases, focusing on their participation in cellular communication and their value as biomarkers. Methods: Bibliography search strategy includes publications in English from peer-reviewed journals listed in PubMed database from 2000–January 2022. Key Content and Findings: A rapidly growing kidney disease-specific extracellular miRNA signature coupled to cellular export/import mechanisms involving vesicle trafficking, protein carriers and miRNA leakage has been identified in the last decade due to the developments in genomics and bioinformatics. However, besides attempts to model the complexity of the networks and regulatory mechanisms of miRNAs involved in each kidney disease, in the majority of cases definitive or causative roles have not been established yet. Conclusions: MiRNAs provide the opportunity to explore novel serum and urine biomarkers of kidney disease, as well as potential therapeutic targets.