NOS2 and Myocardial fibrosis: HUMSCs-derived exosomes loaded with a miR-29b mimic suppressed expression of interleukin 1β (IL-1β)/-6, tumor necrosis factor alpha (TNF-α), and inducible nitric oxide synthase (iNOS) and reduced myocardial fibrosis when delivered through a microneedle patch to a myocardial infarction [51].