Factors associated with estrogen receptors-α (ER-α) and -β (ER-β) and progesterone receptor abundance in obese and non obese pre- and post-menopausal women

There is scarce information about the factors associated with estrogen receptors (ER) at menopause. In 113 volunteers pre- and post-menopausal healthy women, grouped as with and without obesity, estrogen receptors-α and -β, and progesterone receptor (PR) were measured by immunohistochemistry in skin punch biopsies obtained from the external gluteal area. In pre-menopausal women, biopsies and a blood sample were performed between days 7 and 14 of the cycle. Serum hormone levels were measured by immunoradiometric assay or radioimmunoassay. After menopause, ER and PR amounts decreased significantly. At pre-menopause, obese women had lower PR levels than non obese (P < .006). In the post-menopausal group, obese women showed higher ER-α (P < .03) and ER-β (P < .02) levels than the non obese group. In the analysis of factors associated with the amount of steroid receptors for the total group, log[ER-α], log[ER-β], and log[PR] were associated with age (P < .002, <.005, and <.004, respectively). The log[ER-α] was also associated with log[FSH] (P < .0008); meanwhile, the log[PR] showed a marginal correlation with log[FSH]. In pre-menopausal women no factor associated with any of the three receptors was found. In post-menopausal women log[ER-α] was associated with log[estrone] and log[DHEAS] (P < .003 and <.02, respectively). log[PR] was associated with BMI (P < .002), years since menopause (P < .05), and log[DHEAS] (P < .003). We concluded that ER and PR diminish sharply at post-menopause. At this stage the amount of receptors depends on several factors such as BMI, years since menopause, and androgen precursors.