Administration of recombinant human GHRH-1,44-amide for 3 months reduces abdominal visceral fat mass and increases physical performance measures in postmenopausal women

Abstract

A recent study indicated that twice-daily s.c. administration of a high dose of recombinant human GHRH-1,44-amide (GHRH) for 90 days can alter body composition in healthy older men. No data establish whether this is also true in postmenopausal women. The present study tests the hypothesis that the same GHRH regimen applied in women will: (i) elevate both IGF-I and GH concentrations; and (ii) reduce abdominal visceral fat mass, augment total body water and enhance functional performance. Ten postmenopausal volunteers underwent baseline study and then received 1 mg GHRH twice daily s.c. for 3 months. Statistical comparisons were made with pre-intervention baseline data. GHRH administration stimulated: (i) a mean 98 +/- 14% elevation of overnight GH concentrations after administration of the peptide for 1 and 3 months (P < 0.005); (ii) a sustained 71 +/- 3.5% rise in IGF-I concentrations over the interval from 2 weeks to 3 months (P < 0.0012); (iii) a 16 +/- 7% reduction in abdominal visceral fat mass (P = 0.029) and a 14 +/- 5% increase in tri-tiated water space (P < 0.025); (iv) an abbreviation of the times required to walk 30 m (P = 0.015) and ascend two flights of stairs (P = 0.003). Most (70%) subjects experienced local skin reactivity. There were no systemic adverse events. A 3-month regimen of GHRH supplementation in postmenopausal women can stimulate GH and IGF-I production, reduce abdominal visceral fat and improve selected measures of physical performance, while inducing significant local skin reactivity.