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Updated: Mar 28, 2026

Investigating the Pathogenesis of MYH7 Mutation Gly823Glu in Familial Hypertrophic Cardiomyopathy using a Mouse Model
Published on: August 8, 2022
Homocysteine induces cardiac hypertrophy by up-regulating ATP7a expression
Zhanwei Cao1, Yanzhou Zhang2, Tongwen Sun3
1Department of Cardiology, General Hospital of Pingmei Shenma Medical Group Pingdingshan 467000, P.R. China.
Aims:
The aim of the study is to investigate the molecular mechanism by which homocysteine (Hcy) induces cardiac hypertrophy.
Methods:
Primary cardiomyocytes were obtained from baby Sprague-Dawley rats within 3 days after birth. Flow cytometry was used to measure cell sizes. Quantitative real-time polymerase chain reaction was performed to measure the expression of β-myosin heavy chain and atrial natriuretic peptide genes. Western blotting assay was employed to determine ATP7a protein expression. Cytochrome C oxidase (COX) activity test was used to evaluate the activity of COX. Atomic absorption spectroscopy was performed to determine copper content. siRNAs were used to target-silence the expression of ATP7a.
Results:
Hcy induced cardiac hypertrophy and increased the expression of cardiac hypertrophy-related genes. ATP7a was a key factor in cardiac hypertrophy induced by Hcy. Reduced ATP7a expression inhibited cardiac hypertrophy induced by Hcy. Elevated ATP7a expression induced by Hcy inhibited COX activity. Enhanced ATP7a expression inhibited COX activity by lowering intracellular copper content.
Conclusions:
Hcy elevates ATP7a protein expression, reduces copper content, and lowers COX activity, finally leading to cardiac hypertrophy.
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