Estro-progestin supplementation enhances the growth hormone secretory responsiveness to ghrelin infusion in postmenopausal women

Objective

To assess the effects of estro-progestin supplementation on ghrelin-mediated GH release, we studied the consequence of ghrelin or saline injection before and after 60 days of hormone therapy or placebo administration in postmenopausal subjects.

Design

A prospective double blind, placebo-controlled, and parallel cohort study.

Setting

Catholic University of Sacred Heart, Operative Division of Endocrinological Gynecology.

Patient(s)

Eighteen postmenopausal women participated in the study.

Intervention(s)

Ten women were randomized to receive estro-progestin treatment (2 mg of hemihydrate E₂ and 10 mg of dydrogesterone in a continuous sequential regimen); eight women were treated with placebo. All patients underwent in a randomized order a ghrelin test (1 μg/kg IV bolus) or a saline infusion (2-mL IV bolus) on two different days, before and after 60 days of treatment.

Main Outcome Measure(s)

Basal hormonal assays, including ghrelin basal levels. The GH levels were measured at baseline and after 15, 30, 60, 90 minutes of ghrelin or saline injection.

Result(s)

The acute ghrelin injection released a notable GH secretion in all postmenopausal women. After estro-progestin therapy the ghrelin-stimulated GH response was significantly higher than before treatment. In particular, the percent increase of ghrelin GH-releasing effect, expressed as incremental area under the curve (AUCi-GH) was more than 50% after hormone therapy.

Conclusion(s)

In postmenopausal women estro-progestin treatment clearly influenced the ghrelin-stimulated GH secretion.

Key Words: Hormone therapy, ghrelin, growth hormone, menopause