Molecular and mechanical synergy: cross-talk between integrins and growth factor receptors

The full repertoire of molecules and mechanisms which lead to cardiac hypertrophy are poorly understood. Many studies over the last several decades have shown how various growth factors are involved in the hypertrophic response. It has also been intuitively obvious that mechanical mechanisms which impose hemodynamic loads on the working myocardium must also be involved in this process. Integrins are cell adhesion receptors that are potent bi-directional signaling molecules. They are cellular mechanoreceptors in many cells and are clearly one of the molecules which orchestrate mechano-biochemical coupling in the heart. In recent years they too have been shown to be involved in the hypertrophic response pathway. This review will detail background information on integrins in general, discuss integrins in the myocardium and illustrate how integrin and growth factor signaling pathways might combinatorially function in the heart.