Myofibrillar remodeling in cardiac hypertrophy, heart failure and cardiomyopathies

Jarmila Machackova1, Judit Barta, Naranjan S Dhalla

  • 1Institute of Cardiovascular Sciences, St Boniface General Hospital Research Center, Depatment of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.

Insights

Cardiac remodeling and heart failure involve changes in heart muscle proteins. Myofibrillar remodeling, affecting contractile and regulatory proteins, is linked to cardiac dysfunction in heart disease.

Area of Science:

  • Cardiovascular Research
  • Molecular Cardiology
  • Biochemistry

Background:

  • Pathological conditions frequently cause cardiac remodeling and myocardial dysfunction.
  • Mechanisms underlying the transition from adaptive to maladaptive cardiac changes and heart failure development remain unclear.

Purpose of the Study:

  • This review focuses on myofibrillar remodeling in hypertrophied and failing myocardium across various heart diseases.
  • It aims to identify molecular and biochemical alterations in myofibrils, contractile proteins, and regulatory proteins.

Main Methods:

  • Review of extensive studies on subcellular structures, signal transduction, and metabolism in cardiovascular disorders.
  • Analysis of reported changes in gene expression for contractile and regulatory proteins.
  • Examination of myofibrillar remodeling resulting from proteolysis, oxidation, and phosphorylation.

Main Results:

  • Gene expression changes in contractile and regulatory proteins are observed in failing hearts and heart diseases.
  • These alterations may precede heart failure, cardiac hypertrophy, and cardiomyopathies.
  • Myofibrillar remodeling, involving protein modifications, is described in failing hearts of diverse etiologies.

Conclusions:

  • Myofibrillar remodeling is associated with cardiac dysfunction.
  • Alterations in contractile and regulatory proteins are contingent upon the specific heart disease type and its progression stage.
Abstract

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