Dataset Information

Sexual Dimorphism in Cardiac Transcriptome Associated with a Troponin C Murine Model of Hypertrophic Cardiomyopathy

ABSTRACT: Heart disease remains the number one killer of women in the US. Nonetheless, studies in women and female animal models continue to be underrepresented in cardiac research. Hypertrophic cardiomyopathy (HCM), the most commonly inherited cardiac disorder, has been tied to sarcomeric protein variants. Among the susceptible genes, TNNC1—encoding cardiac troponin C (cTnC)—has contributed to a substantial HCM phenotype in mice. In this study we sought to characterize the sexual dimorphism observed within cardiac physiology and transcriptomics of adult male and female mice bearing the HCM-associated cTnC-A8V point mutation. The HCM mice showed a significant decrease in stroke volume, left ventricular diameter, volume, and relative wall thickness. Importantly, isovolumetric contraction time was significantly higher for female HCM mice. RNA sequencing revealed several altered canonical pathways within the HCM mice vs WT groups including an increase in EIF2 signaling, ILK signaling, actin nucleation by ARP-WASP complex, regulation of actin-based motility by Rho, VDR/RXR activation, and glutathione redox reactions pathways. In contrast, Valine Degradation, TCA Cycle II, Methionine Degradation, and Inositol Phosphate Compound pathways were notably down regulated in HCM mice. HCM male vs. female mice followed similar trends of the canonical pathways altered between the HCM and WT. Interestingly, seven of the genes that were differentially expressed in both the WT and HCM male vs female comparisons changed directions in fold change between the sexes. These data suggest a sexually-dimorphic HCM phenotype and identify several key pathways and genes that could be critical to sex differences seen in disease manifestation.

ORGANISM(S): Mus musculus

PROVIDER: GSE144098 | GEO | 2020/01/23

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Aims: A mutation in the phospholamban (PLN) gene, leading to deletion of Arg14 (R14del), has been associated with malignant arrhythmias and ventricular dilation. Identifying pre-symptomatic carriers with vulnerable myocardium is crucial because arrhythmia can result in sudden cardiac death, especially in young adults with PLN-R14del mutation. This study aimed at assessing the efficiency and efficacy of in vivo genome editing, using CRISPR/Cas9 and a cardiotropic adeno-associated virus (AAV9), in improving cardiac function in young adult mice expressing the human PLN-R14del. Methods and Results: Humanized mice were generated expressing human wild-type (hPLN-WT) or mutant (hPLN-R14del) PLN in the heterozygous state, mimicking human carriers. Cardiac magnetic resonance imaging at 12 weeks of age showed bi-ventricular dilation and increased stroke volume in mutant vs. WT mice, with no deficit in ejection fraction or cardiac output. Challenge of ex vivo hearts with isoproterenol and rapid pacing unmasked higher propensity for sustained ventricular tachycardia (VT) in hPLN-R14del relative to hPLN-WT. Specifically, the VT threshold was significantly reduced (20.3±1.2 Hz in hPLN-R14del vs. 25.7±1.3 Hz in WT, p<0.01) reflecting higher arrhythmia burden. To inactivate the R14del allele, mice were tail-vein-injected with AAV9.CRISPR/Cas9/gRNA or AAV9 empty capsid (controls). CRISPR-Cas9 efficiency was evaluated by droplet digital PCR and NGS-based amplicon sequencing. In vivo gene editing significantly reduced end diastolic and stroke volumes in hPLN-R14del CRISPR-treated mice compared to controls. Susceptibility to VT was also reduced, as the VT threshold was significantly increased relative to controls (30.9±2.3 Hz vs. 21.3±1.5 Hz; p<0.01). Conclusions: This study is the first to show that disruption of hPLN-R14del allele by AAV9- CRISPR/Cas9 improves cardiac function and reduces VT susceptibility in humanized PLN-R14del mice, offering preclinical evidence for translatable approaches to therapeutically suppress the arrhythmogenic phenotype in human patients with PLN-R14del disease.

Dataset Information

Sexual Dimorphism in Cardiac Transcriptome Associated with a Troponin C Murine Model of Hypertrophic Cardiomyopathy

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure