Clinical endocrinology
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Clinical endocrinology · Dec 1998
Comparative StudyThe IGF-I response to very low rhGH doses is preserved in human ageing.
The activity of the GH/IGF-I axis varies during life and is clearly reduced in the elderly. In fact, GH, IGF-I and IGFBP-3 levels in older people are clearly reduced and similar to those observed in patients with GH deficiency. The declining activity of the GH/IGF-I axis with advancing age may contribute to changes in body composition, structure, function and metabolism. In fact, treatment with pharmacological doses of rhGH restored plasma IGF-I levels, increased lean body mass and muscle strength while decreased adipose tissue mass in healthy elderly subjects. At present it is unclear whether peripheral GH sensitivity is preserved in aging. To clarify this point, we aimed to verify the effect of both single dose and short term treatment with very low rhGH doses on the IGF-I levels in normal elderly subjects. Normal young adults were studied as controls. ⋯ Our data demonstrate that IGF-I levels in aging are reduced but the peripheral sensitivity to rhGH is preserved. In fact, in aged subjects the percentage rhGH-induced IGF-I increase is similar or even highe