Regulation of energy expenditure by estradiol in premenopausal women.
Suppressing sex hormones in women for 1 wk reduces resting energy expenditure (REE). The effects of more chronic suppression on REE and other components of total energy expenditure (TEE), and whether the reduction in REE is specifically due to loss of estradiol (E2), are not known. We compared the effects of 5 mo of sex hormone suppression (gonadotropin releasing hormone agonist therapy, GnRHAG) with placebo (PL) or E2 add-back therapy on REE and the components of TEE. Premenopausal women received GnRHAG (leuprolide acetate 3.75 mg/mo) and were randomized to receive transdermal therapy that was either E2 (0.075 mg/d; n = 24; means ± SD, aged = 37 ± 8 yr, BMI = 27.3 ± 6.2 kg/m(2)) or placebo (n = 21; aged = 34 ± 9 yr, BMI = 26.8 ± 6.2 kg/m(2)). REE was measured by using a metabolic cart, and TEE, sleep EE (SEE), exercise EE (ExEE, 2 × 30 min bench stepping), non-Ex EE (NExEE), and the thermic effect of feeding (TEF) were measured by using whole room indirect calorimetry. REE decreased in GnRHAG+PL [mean (95% CI), -54 (-98, -15) kcal/d], but not GnRHAG+E2 [+6 (-33, +45) kcal/d] (difference in between-group changes, P < 0.05). TEE decreased in GnRHAG+PL [-128 (-214, -41) kcal/d] and GnRHAG+E2 [-96 (-159, -32) kcal/d], with no significant difference in between-group changes (P = 0.55). SEE decreased similarly in both GnRHAG+PL [-0.07 (-0.12, -0.03) kcal/min] and GnRHAG+E2 [-0.07 (-0.12, -0.02) kcal/min]. ExEE decreased in GnRHAG+PL [-0.46 (-0.79, -0.13) kcal/min], but not GnRHAG+E2 [-0.30 (-0.65, +0.06) kcal/min]. There were no changes in TEF or NExEE in either group. In summary, chronic pharmacologic suppression of sex hormones reduced REE and this was prevented by E2 therapy.
Division of Endocrinology, Metabolism, and Diabetes Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado and Denver Veterans Affairs Medical Center, Denver, Colorado ed.melanson@ucdenver.edu.
Edward L
EL
Melanson
Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado and Denver Veterans Affairs Medical Center, Denver, Colorado.
Kathleen M
KM
Gavin
Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado and Denver Veterans Affairs Medical Center, Denver, Colorado.
Karen L
KL
Shea
Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado and.
Pamela
P
Wolfe
Division of Endocrinology, Metabolism, and Diabetes Denver Veterans Affairs Medical Center, Denver, Colorado.
Margaret E
ME
Wierman
Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado and Denver Veterans Affairs Medical Center, Denver, Colorado.
Robert S
RS
Schwartz
Division of Geriatric Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado and Denver Veterans Affairs Medical Center, Denver, Colorado.
Wendy M
WM
Kohrt
D000328:Adult; D001823:Body Composition; D015519:Bone Density; D004311:Double-Blind Method; D004734:Energy Metabolism / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology*; D015444:Exercise; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006801:Humans; D016729:Leuprolide / Q000009:adverse effects*; D008875:Middle Aged; D017697:Premenopause; D055070:Resistance Training; D055815:Young Adult
D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D016729:Leuprolide
estradiol; gonadotropin releasing hormone; premenopausal women; resistance exercise; room calorimetry