PPARD and congestive heart failure: PPARs belong to the nuclear hormone receptor family, acting as ligand-activated transcription factors, and exist in 3 isoforms: PPARα (NR1C1), PPARβ/δ(NR1C2), and PPARγ (NR1C3).[34] Specifically, PPARβ/δis the predominant subtype expressed in cardiac tissue.[35] Conditional deletion of PPARβ/δin cardiomyocytes has been associated with myocardial lipid accumulation and congestive heart failure with reduced survival.