Endothelin‐1 Induces Myofibrillar Disarray and Contractile Vector Variability in Hypertrophic Cardiomyopathy–Induced Pluripotent Stem Cell–Derived Cardiomyocytes

Abstract

BackgroundDespite the accumulating genetic and molecular investigations into hypertrophic cardiomyopathy (HCM), it remains unclear how this condition develops and worsens pathologically and clinically in terms of the genetic–environmental interactions. Establishing a human disease model for HCM would help to elucidate these disease mechanisms; however, cardiomyocytes from patients are not easily obtained for basic research. Patient‐specific induced pluripotent stem cells (iPSCs) potentially hold much promise for deciphering the pathogenesis of HCM. The purpose of this study is to elucidate the interactions between genetic backgrounds and environmental factors involved in the disease progression of HCM.Methods and ResultsWe generated iPSCs from 3 patients with HCM and 3 healthy control subjects, and cardiomyocytes were differentiated. The HCM pathological phenotypes were characterized based on morphological properties and high‐speed video imaging. The differences between control and HCM iPSC‐derived cardiomyocytes were mild under baseline conditions in pathological features. To identify candidate disease‐promoting environmental factors, the cardiomyocytes were stimulated by several cardiomyocyte hypertrophy‐promoting factors. Interestingly, endothelin‐1 strongly induced pathological phenotypes such as cardiomyocyte hypertrophy and intracellular myofibrillar disarray in the HCM iPSC‐derived cardiomyocytes. We then reproduced these phenotypes in neonatal cardiomyocytes from the heterozygous Mybpc3‐targeted knock in mice. High‐speed video imaging with motion vector prediction depicted physiological contractile dynamics in the iPSC‐derived cardiomyocytes, which revealed that self‐beating HCM iPSC‐derived single cardiomyocytes stimulated by endothelin‐1 showed variable contractile directions.ConclusionsInteractions between the patient's genetic backgrounds and the environmental factor endothelin‐1 promote the HCM pathological phenotype and contractile variability in the HCM iPSC‐derived cardiomyocytes.

Human Induced Pluripotent Stem Cells as a Platform for Personalized and Precision Cardiovascular Medicine

“…It should be noted that the R173W mutation identified in these DCM patients had not been previously reported, and was discovered in this family cohort following exome sequencing of the skin fibroblasts used to generate hiPSCs. In separate studies, hiPSC-CMs carrying DCM-associated mutations in the spliceosome RNA-binding motif protein 20 (RBM20), lamin A/C (LMNA/C), or desmin (DES) genes (243,275,304) also demonstrated abnormalities that closely recapitulate the morphological and functional phenotypes of the affected human heart, as outlined in hiPSC models of HCM associated with thick myofilament myosin heavy chain 7 (MYH7) (89,148) or myosin binding protein C3 (MYBPC3) (262) mutations showed that in vitroderived hiPSC-CMs are significantly enlarged, as seen in the diseased human myocardium. hiPSC-CMs also demonstrated increased myofibril content, contractile arrhythmias (DADs), Ca 2ϩ cycling perturbations, and intracellular Ca 2ϩ elevation, which were worsened by adrenergic stimulation (e.g., with isoproterenol) or environmental exposure to the potent vasoconstrictor endothelin-1 (ET-1) (310).…”

Induced Pluripotent Stem Cells for Cardiovascular Disease: From Product-Focused Disease Modeling to Process-Focused Disease Discovery

“…Additional cardiomyopathy models have been generated from patient-specific iPS cells with hypertrophic cardiomyopathy (HCM) [22, 39, 40]. Compared to healthy controls, iPS cell-derived cardiomyocytes from HCM patients showed increased cellular size, sarcomeric disorganization and greater nuclear localization of NFATC4, all signatures of a hypertrophic state.…”

Generation of Endothelial and Smooth Muscle Cells from Werner Syndrome-Specific Induced Pluripotent Stem Cells

“…64 (3), [207][208][209][210][211][212][213][214][215] model is required to fully understand the pathophysiology. The generation of human induced pluripotent stem cells (iPSCs) from patients with hereditary diseases, and the differentiation of these diseasespecific iPSCs into various types of cells holds the potential for elucidating the pathogenesis of complex human diseases 15) -20) . These iPSC-derived differentiated cells have enabled the supply of a sufficient number of human cells with genetic mutations for basic research and drug screening 21)- 24) .…”