Adipose Tissue Sex Steroids in Postmenopausal Women with and without Menopausal Hormone Therapy.

Abstract

The decrease in serum estrogens after menopause is associated with a shift from a gynoid to an android adipose tissue (AT) distribution. Menopausal hormone therapy (HT) mitigates this change and accompanying metabolic dysfunction, but its effects on AT sex steroid metabolism have not been characterized. We studied effects of HT on subcutaneous and visceral AT estrogen and androgen concentrations and metabolism in postmenopausal women. Serum and subcutaneous and visceral AT from 63 postmenopausal women with (n=50) and without (n=13) per oral HT were analyzed for estrone, estradiol, progesterone, testosterone, androstenedione, dehydroepiandrosterone, and serum estrone sulfate using liquid chromatography-tandem mass spectrometry. Steroid sulfatase activity was measured using radiolabeled precursors. mRNA expression of genes encoding sex steroid-metabolizing enzymes and receptors was performed using real-time reverse transcription quantitative polymerase chain reaction. HT users had 4- to 7-fold higher concentrations of estrone and estradiol in subcutaneous and visceral AT, and 30% lower testosterone in visceral AT compared to non-users. Estrogen-to-androgen ratios were 4- to 12-fold higher in AT of users compared to non-users of HT. In visceral AT, estrogen-to-androgen ratios increased with HT estradiol dose. AT to serum ratios of estrone and estradiol remained high in HT users. Higher local estrogen to androgen ratios and high AT to serum ratios of estrogen concentrations in HT users suggest that HT may significantly influence intracrine sex steroid metabolism in AT, and these local changes could be involved in the preventive effect of HT on menopause-associated abdominal adiposity.