Nanoparticle-Hydrogel System for Post-myocardial Infarction Delivery of MicroRNA.

Effective therapies for cardiac repair and regeneration after myocardial infarction (MI) are rather limited. Although microRNAs (miRs) are known to play an important role in improving cardiac function after MI at a cellular level, delivering and retaining miRs at the target site has been challenging. To address this dilemma, several miR carriers have been developed, but these face their own limitations such as immunogenicity and poor targeting to the infarct site. In this Perspective, we summarize different mechanisms for miR administration and localization to cardiac tissue, with a specific focus on the clinically relevant injectable hydrogel and nanoparticle system developed by Yang et al. and reported in this issue of ACS Nano. We also highlight future directions for this field and outline the remaining unanswered questions.