In a mouse model of myocardial infarction, the authors showed that miRNA-27b mimic had overall beneficial effects, including increased vascularization, decreased fibrosis, and increased ejection fraction, at least in part due to the decreased expression of delta-like ligand 4 (Dll4), peroxisome proliferator-activated receptor γ (PPARγ), and IL-10 [25]. Here, DLL4 is linked to myocardial infarction.