Dataset Information

Mitochondrial complex I defect and increased fatty acid oxidation enhance protein lysine acetylation in the diabetic heart.

ABSTRACT: Cardiomyopathy is a major complication of diabetes. Our study was aimed to identify the sites of mitochondrial dysfunction and delineate its consequences on mitochondrial metabolism in a model of type 1 diabetes.Diabetes was induced by streptozotocin injection to male Lewis rats. We found a decrease in mitochondrial biogenesis pathway and electron transport chain complex assembly that targets Complex I. Oxidation of Complex II and long-chain fatty acid substrates support the electron leak and superoxide production. Mitochondrial defects do not limit fatty acid oxidation as the heart's preferred energy source indicating that the diabetic heart has a significant reserve in Complex I- and II-supported ATP production. Both mitochondrial fatty acid oxidation and Complex I defect are responsible for increased protein lysine acetylation despite an unchanged amount of the NAD(+)-dependent mitochondrial deacetylase sirt3. We quantitatively analysed mitochondrial lysine acetylation post-translational modifications and identified that the extent of lysine acetylation on 54 sites in 22 mitochondrial proteins is higher in diabetes compared with the same sites in the control. The increased lysine acetylation of the mitochondrial trifunctional protein subunit ? may be responsible for the increased fatty acid oxidation in the diabetic heart.We identified the specific defective sites in the electron transport chain responsible for the decreased mitochondrial oxidative phosphorylation in the diabetic heart. Mitochondrial protein lysine acetylation is the common consequence of both increased fatty acid oxidation and mitochondrial Complex I defect, and may be responsible for the metabolic inflexibility of the diabetic heart.

SUBMITTER: Vazquez EJ

PROVIDER: S-EPMC6279178 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mitochondrial complex I defect and increased fatty acid oxidation enhance protein lysine acetylation in the diabetic heart.

Vazquez Edwin J EJ Berthiaume Jessica M JM Kamath Vasudeva V Achike Olisaemeka O Buchanan Elizabeth E Montano Monica M MM Chandler Margaret P MP Miyagi Masaru M Rosca Mariana G MG

Cardiovascular research 20150622 4

<h4>Aims</h4>Cardiomyopathy is a major complication of diabetes. Our study was aimed to identify the sites of mitochondrial dysfunction and delineate its consequences on mitochondrial metabolism in a model of type 1 diabetes.<h4>Methods and results</h4>Diabetes was induced by streptozotocin injection to male Lewis rats. We found a decrease in mitochondrial biogenesis pathway and electron transport chain complex assembly that targets Complex I. Oxidation of Complex II and long-chain fatty acid su ...[more]

PMID: 26101264

Similar Datasets

Project description:INTRODUCTION:The childhood heart disease of Friedreich's Ataxia (FRDA) is characterized by hypertrophy and failure. It is caused by loss of frataxin (FXN), a mitochondrial protein involved in energy homeostasis. FRDA model hearts have increased mitochondrial protein acetylation and impaired sirtuin 3 (SIRT3) deacetylase activity. Protein acetylation is an important regulator of cardiac metabolism and loss of SIRT3 increases susceptibility of the heart to stress-induced cardiac hypertrophy and ischemic injury. The underlying pathophysiology of heart failure in FRDA is unclear. The purpose of this study was to examine in detail the physiologic and acetylation changes of the heart that occur over time in a model of FRDA heart failure. We predicted that increased mitochondrial protein acetylation would be associated with a decrease in heart function in a model of FRDA. METHODS:A conditional mouse model of FRDA cardiomyopathy with ablation of FXN (FXN KO) in the heart was compared to healthy controls at postnatal days 30, 45 and 65. We evaluated hearts using echocardiography, cardiac catheterization, histology, protein acetylation and expression. RESULTS:Acetylation was temporally progressive and paralleled evolution of heart failure in the FXN KO model. Increased acetylation preceded detectable abnormalities in cardiac function and progressed rapidly with age in the FXN KO mouse. Acetylation was also associated with cardiac fibrosis, mitochondrial damage, impaired fat metabolism, and diastolic and systolic dysfunction leading to heart failure. There was a strong inverse correlation between level of protein acetylation and heart function. CONCLUSION:These results demonstrate a close relationship between mitochondrial protein acetylation, physiologic dysfunction and metabolic disruption in FRDA hypertrophic cardiomyopathy and suggest that abnormal acetylation contributes to the pathophysiology of heart disease in FRDA. Mitochondrial protein acetylation may represent a therapeutic target for early intervention.

Dataset Information

Mitochondrial complex I defect and increased fatty acid oxidation enhance protein lysine acetylation in the diabetic heart.

Publications

Mitochondrial complex I defect and increased fatty acid oxidation enhance protein lysine acetylation in the diabetic heart.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets