Abstract
Peripartum cardiomyopathy (PPCM) is a pregnancy-associated form of systolic heart failure that develops when hemodynamic, metabolic, and hormonal stress of late gestation exceeds maternal cardiac adaptive capacity. While vascular, inflammatory, and genetic contributions have been implicated in PPCM, the integrated molecular programs connecting pregnancy-related stress to cardiomyocyte failure remain poorly defined. To elucidate these mechanisms, we performed a transcriptome-wide RNA seq of left ventricles from females with PPCM and non-failing female normal donor controls. Differential expression analysis identified 2891 genes with altered expressions (1491 upregulated, 1400 downregulated; fold change ≥ 2, FDR < 0.05). Ingenuity pathway analysis (IPA) revealed the activation of protein ubiquitination pathways, EIF2 signaling, mitochondrial dysfunction, and apoptosis pathways. Upstream regulator analysis indicated the suppression of mitochondrial protease CLPP (Z = -4.075) and activation of COPS5 (Z = +5.982) and TEAD1 (Z = +5.00), delineating dual regulatory modules of disease remodeling. Integrated network analysis demonstrated a loss of protein quality control and survival signaling with the activation of stress response and translational repression programs. This signifies a collapse of proteostasis and maladaptive adaptation. Collectively, these data define PPCM as a disorder of failed proteostasis and impaired translational homeostasis. Our analysis provides a systems-level framework connecting PPCM to ventricular dysfunction with potential therapeutic targets in mitochondria, protein quality-control, integrated stress-response, and COP9 signaling pathways.