Effects of growth hormone and/or sex steroid administration on whole-body protein turnover in healthy aged women and men.

Aging is associated with reduced activities of the growth hormone (GH), insulin-like growth factor I (IGF-I), and sex steroid axes, and with decreased lean body mass and protein synthesis. Using a randomized, double-blinded, placebo-controlled design, we studied the effects of 6 months of administration of GH alone, sex hormone alone (hormone replacement therapy in women, testosterone enanthate [T] in men), or GH plus sex hormone on protein turnover in healthy men (n=60) and women (n=43), aged 65 to 88 years (mean, 71+/-4.4 years).

Growth hormone and sex steroid administration in healthy aged women and men: a randomized controlled trial.

Context: Hormone administration to elderly individuals can increase lean body mass (LBM) and decrease fat, but interactive effects of growth hormone (GH) and sex steroids and their influence on strength and endurance are unknown.

Objective: To evaluate the effects of recombinant human GH and/or sex steroids on body composition, strength, endurance, and adverse outcomes in aged persons.

Design, Setting, And Participants: A 26-week randomized, double-blind, placebo-controlled parallel-group trial in healthy, ambulatory, community-dwelling US women (n = 57) and men (n = 74) aged 65 to 88 years recruited between June 1992 and July 1998.

Growth hormone and sex steroid effects on bone metabolism and bone mineral density in healthy aged women and men.

Background: Aging is associated with concomitant declines in activity of the growth hormone (GH) and gonadal steroid axes, and in bone mineral density (BMD), in both sexes. Long-term estrogen replacement slows bone loss and prevents fractures in postmenopausal women, whereas the effects of supplementation of GH or testosterone on bone metabolism and BMD in aged individuals remains uncertain.

Methods: Using a randomized, placebo-controlled, double-blind study design, we investigated the separate and interactive effects of 6 months of administration of recombinant human GH and/or gonadal steroids on bone biochemical markers and BMD in 125 healthy, older (>65 years) women (n = 53) and men (n = 72) with age-related reductions in GH and gonadal steroids.