STAT1 and heart failure: STAT proteins are expressed in the mature heart, and in particular STAT1 and STAT3 play roles in ischemic heart disease, with STAT1 contributing to the decrease of myocardial cells by increasing apoptosis, while STAT3 being cardioprotective by decreasing reactive oxygen species, but related to early remodeling of the heart that then leads to heart failure (Knight et al., 2012).