GSE158889
YAP/TAZ deficiency reprograms macrophage phenotype and improves infarct healing and cardiac function after myocardial infarction
Adverse cardiac remodeling after myocardial infarction (MI) causes structural and functional changes in the heart leading to heart failure. The initial pro-inflammatory response followed by an anti-inflammatory or reparative response post-MI is essential for minimizing the myocardial damage, healing, and scar formation. Bone marrow-derived macrophages (BMDMs) are recruited to the injured myocardium and essential for cardiac repair as they can adopt both pro-inflammatory (M1) or anti-inflammatory/reparative (M2) phenotypes to modulate inflammatory and reparative response, respectively. YAP and TAZ are the key mediators of the Hippo signaling pathway and essential for cardiac regeneration and repair. However, their role in macrophage polarization and post-MI inflammation, remodeling, and healing are not well established. Here, we demonstrate that expression of YAP and TAZ is increased in macrophages undergoing M1 or M2 polarization. Genetic deletion of YAP/TAZ leads to impaired M1 polarization and enhanced M2 polarization. Consistently, YAP activation/overexpression enhanced M1 and impaired M2 polarization. We show that YAP/TAZ promote M1 polarization by increasing IL6 expression, and impede M2 polarization by decreasing Arg1 expression through interaction with the HDAC3-NCoR1 repressor complex. These changes in macrophages polarization due to YAP/TAZ deletion results in reduced fibrosis, and hypertrophy and increased angiogenesis, leading to improved cardiac function after MI. Also, YAP activation augmented MI-induced cardiac fibrosis and remodeling. In summary, we identify YAP/TAZ as important regulators of macrophage-mediated pro- and anti-inflammatory responses post-MI. Overall design: 12 BMDM samples are analyzed comprises of untreated control (n = 3), untreated Yap/Taz knockout (n = 3), LPS/IFNg treated control (n = 3), LPS/IFNg treated Yap/Taz knockout (n = 3)