Effects Of GH And/Or Sex Steriod Administration On Abdominal Subcutaneous And Visceral Fat In Healthy Aged Women And Men

ABSTRACT

Aging is associated with reduced GH, IGD-1, and sex steroid axis activity and with increased abdominal fat. We employed a randomized, double-masked, placebo-controlled, noncross-over design to study the effects of 6 months of administration of GH alone (20 microg/kg BW), sex hormone alone (hormone replacement therapy in women, testosterone enanthate in men), or GH sex hormone on total abdominal area, abdominal sc fat, and visceral fat in 110 healthy women (n=46) and men (n=64), 65-88 year old (mean, 72 year). GH administration increased IGF-1 levels in women (P=0.05) and men (P=0.0001), with the increment in IGF-1 levels being higher in men (P=0.05). Sex steroid administration increased levels of estrogen and testosterone in women and men, respectively (P= 0.05). In women, neither GH, hormone replacement therapy, nor GH hormone replacement therapy altered total abdominal area, sc fat, or visceral fat significantly. In contrast, in men, administration of GH and GH testosterone enanthate decreased total abdominal area by 3.9% and 3.8%, respectively, within group and vs. placebo (P=0.05). Within-group comparisons revealed that sc fat decreased by 10% (P=0.01) after GH, and by 14% (P=0.0005) after GH testosterone enanthate. Compared with placebo, sc fat decreased by 14% (P=0.05) after GH, by 7% (P=0.05) after testosterone enanthate, and by 16% (P 0.0005) after GH testosterone enanthate. Compared with placebo, visceral fat did not decrease significantly after administration of GH, testosterone enanthate, or GH testosterone enanthate. These date suggest that in healthy older individuals, GH and/or sex hormone administration elicits a sexually dimorphic response on sc abdominal fat. The generally proportionate reductions we observed in sc and visceral fat, after 6 months of GH administration in healthy aged men, contrast with the disproportionate reductions of visceral fat reported after a similar period of GH treatment of nonelderly GH deficient men and women. Whether longer term administration of GH or testosterone enanthate, alone or in combination, will reduce abdominal fat distribution-related cardiovascular risk in healthy older men remains to be elucidated.

Journal of Clinical Endocrinology and Metabolism Article
Munzer T, Harman SM, Hees P, Shapiro E, Christmas C, Bellantoni MF, Stevens TE, O’Conner KG, Pabst KM, St Clair C, Sorkin JD, Blackman MR  August 2001, Vol, 86 No. 8 3604