Improved cardiac metabolism and activation of the RISK pathway contributes to improved post-ischemic recovery in calorie restricted mice
Autor: | Grant Masson, Jamie Boisvenue, Carrie-Lynn M. Soltys, Jason R.B. Dyck, Miranda M. Y. Sung |
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Rok vydání: | 2010 |
Předmět: |
Cardiac function curve
medicine.medical_specialty Blotting Western Ischemia Myocardial Reperfusion Injury AMP-Activated Protein Kinases Mice Adenosine Triphosphate AMP-activated protein kinase Internal medicine Drug Discovery medicine Animals Glycolysis Protein kinase B Beta oxidation Genetics (clinical) Caloric Restriction biology Myocardium Fatty Acids AMPK Metabolism medicine.disease Mice Inbred C57BL Endocrinology biology.protein Molecular Medicine Protein Kinases Signal Transduction |
Zdroj: | Journal of Molecular Medicine. 89:291-302 |
ISSN: | 1432-1440 0946-2716 |
Popis: | Recent evidence has suggested that activation of AMP-activated protein kinase (AMPK) induced by short-term caloric restriction (CR) protects against myocardial ischemia-reperfusion (I/R) injury. Because AMPK plays a central role in regulating energy metabolism, we investigated whether alterations in cardiac energy metabolism contribute to the cardioprotective effects induced by CR. Hearts from control or short-term CR mice were subjected to ex vivo I/R and metabolism, as well as post-ischemic functional recovery was measured. Even in the presence of elevated levels of fatty acids, CR significantly improved recovery of cardiac function following ischemia. While rates of fatty acid oxidation or glycolysis from exogenous glucose were similar between groups, improved functional recovery post-ischemia in CR hearts was associated with high rates of glucose oxidation during reperfusion compared to controls. Consistent with CR improving energy supply, hearts from CR mice had increased ATP levels, as well as lower AMPK activity at the end of reperfusion compared to controls. Furthermore, in agreement with the emerging concept that CR is a non-conventional form of pre-conditioning, we observed a significant increase in phosphorylation of Akt and Erk1/2 at the end of reperfusion. These data also suggest that activation of the reperfusion salvage kinase (RISK) pathway also contributes to the beneficial effects of CR in reducing post-ischemia contractile dysfunction. These findings also suggest that short-term CR improves post-ischemic recovery by promoting glucose oxidation, and activating the RISK pathway. As such, pre-operative CR may be a clinically relevant strategy for increasing ischemic tolerance of the heart. |
Databáze: | OpenAIRE |
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