The therapeutic potential of miRNAs in cardiac fibrosis: where do we stand?

Recent developments in basic and clinical science have turned the spotlight to miRNAs for their potential therapeutic efficacy. Since their discovery in 1993, it has become clear that miRNAs act as posttranscriptional regulators of protein expression. Their clinical potential was further highlighted by the results of miRNA-based interventions in small laboratory animals. More importantly, their therapeutic effectiveness has been shown recently in phase 2a clinical studies in patients with hepatitis C virus infection, where inhibition of miRNA-122 showed prolonged and dose-dependent viral suppression. A recent study surprisingly revealed the presence of plant-derived miRNAs in the blood of healthy humans. This finding opens up the possibility to explore miRNA-mediated therapeutics derived from (genetically modified) food. Having arrived at this point in our understanding of miRNAs, we provide an overview of current evidence and future potential of miRNA-based therapeutics, focusing on their application in cardiac fibrosis.