Insulin and the heart
Fotios Iliadis1, Nikolaos Kadoglou, Triantafillos Didangelos
1Diabetes Division, 1st Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece. didang@med.auth.gr
Diabetes Research and Clinical Practice
|August 26, 2011
Summary
Insulin plays a crucial role in heart function by regulating energy use and promoting cell survival. Its actions are vital for maintaining cardiac health, and disruptions in insulin signaling are linked to heart disease.
Area of Science:
- Cardiology
- Metabolic Regulation
- Molecular Biology
Background:
- Insulin is primarily known for regulating glucose metabolism in peripheral tissues.
- The heart utilizes various substrates for energy, with glucose being a key one under insulin's influence.
- Insulin's direct effects on cardiac function and its role in cardiovascular health are increasingly recognized.
Purpose of the Study:
- To review the physiological roles of insulin in the heart.
- To elucidate the molecular mechanisms underlying insulin's cardiac actions.
- To discuss the implications of altered insulin signaling in cardiac pathologies.
Main Methods:
- This review synthesizes existing scientific literature on insulin's cardiac effects.
- Evidence from studies on insulin signaling pathways, including PKB/Akt, is examined.
- Pathological conditions affecting insulin action in the heart are analyzed.
Main Results:
- Insulin enhances cardiac glucose uptake and glycolysis, optimizing energy substrate utilization.
- Insulin promotes cardiomyocyte contraction, relaxation, protein synthesis, and cell survival.
- Insulin stimulates vascular endothelial growth factor (VEGF) production, promoting angiogenesis and improving myocardial perfusion.
- Insulin signaling is impaired in conditions like type 2 diabetes, myocardial ischemia, and cardiac hypertrophy.
Conclusions:
- The heart is a significant target organ for insulin, with crucial physiological functions.
- Insulin signaling pathways, primarily mediated by PKB/Akt, are essential for maintaining cardiac health.
- Dysregulation of insulin action in the heart contributes to the pathogenesis of cardiovascular diseases.
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