Overexpression of mitochondrial creatine kinase preserves cardiac energetics without ameliorating murine chronic heart failure.
Basic Res Cardiol
; 115(2): 12, 2020 01 10.
Article
em En
| MEDLINE
| ID: mdl-31925563
ABSTRACT
Mitochondrial creatine kinase (Mt-CK) is a major determinant of cardiac energetic status and is down-regulated in chronic heart failure, which may contribute to disease progression. We hypothesised that cardiomyocyte-specific overexpression of Mt-CK would mitigate against these changes and thereby preserve cardiac function. Male Mt-CK overexpressing mice (OE) and WT littermates were subjected to transverse aortic constriction (TAC) or sham surgery and assessed by echocardiography at 0, 3 and 6 weeks alongside a final LV haemodynamic assessment. Regardless of genotype, TAC mice developed progressive LV hypertrophy, dilatation and contractile dysfunction commensurate with pressure overload-induced chronic heart failure. There was a trend for improved survival in OE-TAC mice (90% vs 73%, P = 0.08), however, OE-TAC mice exhibited greater LV dilatation compared to WT and no functional parameters were significantly different under baseline conditions or during dobutamine stress test. CK activity was 37% higher in OE-sham versus WT-sham hearts and reduced in both TAC groups, but was maintained above normal values in the OE-TAC hearts. A separate cohort of mice received in vivo cardiac 31P-MRS to measure high-energy phosphates. There was no difference in the ratio of phosphocreatine-to-ATP in the sham mice, however, PCr/ATP was reduced in WT-TAC but preserved in OE-TAC (1.04 ± 0.10 vs 2.04 ± 0.22; P = 0.007). In conclusion, overexpression of Mt-CK activity prevented the changes in cardiac energetics that are considered hallmarks of a failing heart. This had a positive effect on early survival but was not associated with improved LV remodelling or function during the development of chronic heart failure.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Hipertrofia Ventricular Esquerda
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Disfunção Ventricular Esquerda
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Miócitos Cardíacos
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Metabolismo Energético
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Creatina Quinase Mitocondrial
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Insuficiência Cardíaca
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Mitocôndrias Cardíacas
Limite:
Animals
Idioma:
En
Revista:
Basic Res Cardiol
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Reino Unido