The effects of growth hormone and insulin-like growth factor-1 on the aging cardiovascular system and its progenitor cells.

Aging is a major risk factor for the development of cardiovascular disease. Aging is also associated with a decline in the growth hormone (GH) and insulin-like growth factor-1 (IGF-1) axis. This axis impacts endothelial and vascular smooth muscle cell biology, as well as cardiac function. The number of endothelial progenitor cells (EPCs) also decreases with age and is emerging as a surrogate measurement of vascular senescence. Studies suggest that EPCs impact vascular health by modulating vascular repair and function. Current evidence demonstrates that EPC number and function is restored with a GH-mediated increase in serum IGF-1. Modulation of the GH and IGF-1 system may therefore provide a useful therapy in the prevention of age-associated changes in the cardiovascular system and in future regenerative cell-based therapies.