Physiological myocardial hypertrophy: how and why?
Cardiac hypertrophy is defined by augmentation of ventricular mass as a result of increased cardiomyocyte size, and is the adaptive response of the heart to enhanced hemodynamic loads due to either physiological stimuli (post-natal developmental growth, training, and pregnancy) or pathological states (such as hypertension, valvular insufficiency, etc). The mechanisms leading to hypertrophy during pathological and physiological states are distinct but, in general, evidence indicates that hypertrophy results from the interaction of mechanical forces and neurohormonal factors. Hemodynamic overload creates a mechanical burden on the heart and results in stretch of the myocyte and induction of gene expression of cardiac growth factors. Insulin-like growth factor 1 (IGF1) has recently been shown to be the most important cardiac growth factor involved in physiological hypertrophy. In this review, IGF1 and the pathways it triggers will be discussed.
Catalucci
Daniele
D
Department of Medicine, Division of Cardiology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613, USA.
Latronico
Michael V G
MV
Ellingsen
Oyvind
O
Condorelli
Gianluigi
G
D000818:Animals; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D006984:Hypertrophy; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D009206:Myocardium / Q000473:pathology*; D009389:Neovascularization, Pathologic; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011247:Pregnancy; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011941:Receptors, Adrenergic / Q000378:metabolism; D015398:Signal Transduction
D011941:Receptors, Adrenergic; D007334:Insulin-Like Growth Factor I; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt