NOS2 and familial dilated cardiomyopathy: In addition, recent studies have provided important mechanistic insights of BM-MSC biology in the vicinity of inflammation and its ability to decrease the intra cellular levels of IL1β, and TNFα as well as their levels in macrophages thus reducing M1 macrophages activation and consequently iNOS expression which have essential roles in mediating DCM (Jin et al. 2022).