An open access commentary: "The mammalian heart must maintain its structural and functional integrity for decades, yet the response to damage in this vital organ is remarkably inadequate and often results in heart failure. Moreover, patients with chronic heart failure show profound metabolic changes, leading to peripheral abnormalities in addition to an initial cardiac impairment. Several evidences have suggested a relationship between the IGF-1 system and cardiovascular disease. Many cardiovascular risk factors, such as sedentary lifestyle, diabetes, smoking, oxidized low-density lipoprotein, obesity, psychological distress and reduced coronary flow reserve, have been associated with reduced IGF-1 levels. Conversely, human studies indicate that increased levels of IGF-1 are characterized by a decreased incidence of heart failure and mortality in elderly individuals. Nevertheless, the fact that IGF-1 can act either as a circulating hormone or as a local growth factor has confounded previous analyses of animal models in which transgenic IGF synthesized in extra-hepatic tissues was released into the circulation. Locally acting mIGF-1 isoform improves muscle regeneration and counters muscle wasting associated with diseases, including sarcopenia, muscular dystrophy and ALS. By contrast, circulating IGF-1 isoforms have been implicated in the restriction of lifespan and have contrasting effects on the heart when expressed as transgenes, variously promoting cell survival, or inducing prolonged hypertrophy with pathological consequences."

Link: http://www.impactaging.com/papers/v4/n6/full/100466.html

Source:
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