Clinical implications of the reduced activity of the GH-IGF-I axis in older men.

Abstract

During the last decade, a significant body of evidence has accumulated, indicating that IGF-I might play a role in several pathological conditions commonly seen during aging, such as atherosclerosis and cardiovascular disease (CVD), cognitive decline, dementia, sarcopenia and frailty. A vascular protective role for IGF-I has been suggested because of its ability to stimulate nitric oxide production from endothelial and vascular smooth muscle cells. In cross sectional studies, low IGF-I levels have been associated with unfavorable CVD risk factors profile, such as atherosclerosis, abnormal lipoprotein levels and hypertension, while in prospective studies, lower IGF-I levels predict future development of ischemic heart disease. The fall in IGF-I levels with aging correlates with cognitive decline and it has been suggested that IGF-I plays a role in the development of dementia. IGF-I is highly expressed within the brain and is essential for normal brain development. IGF-I has anti-apoptotic and neuroprotective effects and promotes projection neuron growth, dendritic arborization and synaptogenesis. Collectively, these data are consistent with a causal link between the age-related decline in GH and IGF-I levels and cognitive deficits in older persons. Finally, there is evidence of a relationship between declining GH and IGF-I levels and age-related changes in body composition and physical function. However, few studies have documented a precise role of IGF-I in the development of sarcopenia, frailty and poor mobility. We have recently documented that serum IGF-I is significantly associated with measures of muscle strength and physical performance in men and to a lesser extent in women. In conclusion, IGF-I is a pleiotropic hormone that in older persons may positively affect the cardiovascular system, the central nervous system and physical function.

• Authors: G P Ceda, E Dall'Aglio, M Maggio, F Lauretani, S Bandinelli, C Falzoi, W Grimaldi, G Ceresini, F Corradi, L Ferrucci, G Valenti, A R Hoffman
• Journal: Journal of endocrinological investigation (J Endocrinol Invest) Vol. 28 Issue 11 Suppl Proceedings Pg. 96-100 ( 2005) ISSN: 0391-4097 [Print] Italy
• PMID: 16760634 (Publication Type: Journal Article, Review)

Chemical References

• Insulin-Like Growth Factor I
• Growth Hormone

Topics

• Aged
• Aged, 80 and over
• Cardiovascular Diseases (etiology)
• Growth Hormone (metabolism)
• Humans
• Insulin-Like Growth Factor I (metabolism)
• Male
• Memory Disorders
• Motor Activity (physiology)