Abstract 16704: Epigenetic and Morphofunctional Changes in Human Induced Pluripotent Stem Cell-derived Cardiomyocytes Carrying a Mutation Causative of Premature Aging

Introduction: Aging is derived from accumulation of molecular and cellular damage resulting in loss of physiological reserves, individual capacity, and increased risk for cardiovascular disease and death. Life expectancy has been increasing and age related diseases are becoming more prevalent. Hutchinson-Gilford Progeria Syndrome (HGPS) is disease that results in severe age-associated complications starting early in development. Patients with HGPS die at young age of diseases normally seen in the elderly population including cardiovascular complications. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) generated from patients carrying a mutation in the gene encoding Lamin A/C (LMNA2) causative of HGPS provide a unique in vitro model of aging. Hypothesis: HGPS-specific iPSC-CMs provide an unlimited source of cells that recapitulate hallmarks of advanced aging and age-related altered electrophysiology. Methods: iPSC-CMs from a control (MCH iPSCM) and HGPS-specific (167 iPSCM) cell lines were submitted to magnetic bead-assisted cell sorting and plated on PDMS coverslips for formation of matured iPSC-CMs functional syncytia. These cells were compared with single cell patch clamp and optical mapping for analysis of action potentials. Also, samples were submitted to western blot and immunofluorescence for assessment of Lamin A/C, heterochromatin protein 1 (HP1) and chromatin repression marker (H3K9me3). Results: HGPS-specific iPSC-CMs presented hallmarks of HGPS (Figure 1), including nuclear lamina folding and blebbing (arrows and panels E and F); and nuclear fragmentation - arrow head on panel E. There was a 70% decrease in HP1 associated reduction in heterochromatin. HGPS-specific iPSC-CMs had increased action potential duration (panel G). Conclusions: iPSC-CMs carrying a mutation causative of a premature aging syndrome have hallmarks of HGPS that are also present in normal aging and may be used as a model for human heart aging.