Characterization of heterozygous and homozygous mouse models with the most common hypertrophic cardiomyopathy mutation MYBPC3c.2373InsG in the Netherlands

Sarah Hilderink; Maike Schuldt; Max Goebel; Valentijn J Jansen; Emmy Manders; Stan Moorman; Larissa M Dorsch; Frank G van Steenbeek; Jolanda van der Velden; Diederik W D Kuster

doi:10.1016/j.yjmcc.2023.10.008

Characterization of heterozygous and homozygous mouse models with the most common hypertrophic cardiomyopathy mutation MYBPC3_c.2373InsG in the Netherlands

J Mol Cell Cardiol. 2023 Dec:185:65-76. doi: 10.1016/j.yjmcc.2023.10.008. Epub 2023 Oct 14.

Affiliations

¹ Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan 1118, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, the Netherlands.
² Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan 1118, Amsterdam, the Netherlands.
³ Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands; Department of Cardiology, Division Heart & Lungs, University Medical Center Utrecht, Utrecht University, 3508 GA Utrecht, the Netherlands; Regenerative Medicine Center Utrecht, University Medical Center Utrecht, Utrecht University, 3584 CT Utrecht, the Netherlands.
⁴ Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan 1118, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, the Netherlands. Electronic address: d.kuster@amsterdamumc.nl.

PMID: 37844837
DOI: 10.1016/j.yjmcc.2023.10.008

Abstract

Hypertrophic cardiomyopathy (HCM) is frequently caused by mutations in the cardiac myosin binding protein-C (cMyBP-C) encoding gene MYBPC3. In the Netherlands, approximately 25% of patients carry the MYBPC3_c.2373InsG founder mutation. Most patients are heterozygous (MYBPC3^+/InsG) and have highly variable phenotypic expression, whereas homozygous (MYBPC3^InsG/InsG) patients have severe HCM at a young age. To improve understanding of disease progression and genotype-phenotype relationship based on the hallmarks of human HCM, we characterized mice with CRISPR/Cas9-induced heterozygous and homozygous mutations. At 18-28 weeks of age, we assessed the cardiac phenotype of Mybpc3^+/InsG and Mybpc3^InsG/InsG mice with echocardiography, and performed histological analyses. Cytoskeletal proteins and cardiomyocyte contractility of 3-4 week old and 18-28 week old Mybpc3_c.2373InsG mice were compared to wild-type (WT) mice. Expectedly, knock-in of Mybpc3_c.2373InsG resulted in the absence of cMyBP-C and our 18-28 week old homozygous Mybpc3_c.2373InsG model developed cardiac hypertrophy and severe left ventricular systolic and diastolic dysfunction, whereas HCM was not evident in Mybpc3^+/InsG mice. Mybpc3^InsG/InsG cardiomyocytes also presented with slowed contraction-relaxation kinetics, to a greater extent in 18-28 week old mice, partially due to increased levels of detyrosinated tubulin and desmin, and reduced cardiac troponin I (cTnI) phosphorylation. Impaired cardiomyocyte contraction-relaxation kinetics were successfully normalized in 18-28 week old Mybpc3^InsG/InsG cardiomyocytes by combining detyrosination inhibitor parthenolide and β-adrenergic receptor agonist isoproterenol. Both the 3-4 week old and 18-28 week old Mybpc3^InsG/InsG models recapitulate HCM, with a severe phenotype present in the 18-28 week old model.

Keywords: Cardiac myosin binding protein c; Diastolic dysfunction; Hypertrophic cardiomyopathy; Microtubule remodeling; Mouse model.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Cardiomyopathy, Hypertrophic*
Carrier Proteins* / genetics
Carrier Proteins* / metabolism
Cytoskeletal Proteins / genetics
Humans
Mice
Mutation
Netherlands
Phenotype

Substances

Carrier Proteins
Cytoskeletal Proteins