Estrogen Receptor Beta and Mood

Overview

Background: Our previous studies have found that women who had depression during the perimenopause may have mood symptoms again if they stop estrogen therapy. Estrogen acts in the brain and other tissues by binding to estrogen receptors. There are two main types of estrogen receptors. They are estrogen receptor alpha and beta. Several studies have shown that estrogen receptor beta may play an important role in anxiety- and depressive-like behaviors in animals. Objectives: To examine a possible mechanism mediating the effects of estradiol-withdrawal on mood symptoms in asymptomatic postmenopausal women with a past perimenopausal depression. To evaluate the efficacy and safety of a selective estrogen receptor (ER) beta agonist (Lilly Compound LY500307) to prevent estradiol withdrawal-induced mood symptoms. Eligibility: Healthy, non-depressed postmenopausal women, ages 45 to 65, with a well-documented past perimenopause-related depression (within 12 years) and whose mood systems got better with estradiol Design: Participants will be screened with: Medical history Physical exam Blood tests Psychiatric interview Gynecological exam * Participants able to get pregnant must use effective barrier birth control throughout the study. * During the first 3 weeks, participants will wear an estrogen patch. It is 1x2 inches and will be replaced every 3 days. * For the next 3 weeks, participants will take 3 study capsules every morning. They will not know if they get the study drug or placebo. * Some participants will also take a progesterone-like drug for 1 week at the end of the medication phase of the study. * Participants will have 9 one-hour study visits. They will have blood samples and vital signs taken. They will answer questions about mood and behavior symptoms. * Participants will keep a daily log of these symptoms. * Participants will have 2 transvaginal ultrasounds. A probe is temporarily placed 2-3 inches into the vaginal canal and sound waves are used to create pictures of the lining of the uterus. * Participants will have a final visit 4 weeks after stopping the study drug. They will answer questions about mood and side effects.

OBJECTIVE: Depression risk increases during the perimenopause, and depression is cited as a primary reason for resuming menopausal hormone therapy (HT). Community-based epidemiologic studies document a 1.5-3 fold greater risk of first onset and recurrent depressions in women during the perimenopause compared with those who are premenopausal (or who are several years postmenopausal). Observational studies report the emergence of depressive symptoms after the discontinuation of HT in 5-10% of women. The role of estradiol (E2) - either declining or low levels - in the precipitation of perimenopausal depression (PMD) is unknown, largely due to the associational and indirect nature of the evidence linking ovarian function and depression. In study 03-M-0175, our results demonstrated that estradiol withdrawal was associated with a significant increase in depressive symptoms in those women with a past depression during the perimenopause. Of note, the effects of estradiol primarily occur through activation of two receptor subtypes, often with opposing outcomes: estrogen receptor (ER) alpha, and ER beta. Therefore, in this protocol, we examined the ability of a selective ER beta agonist (LY500307) to prevent estradiol withdrawal- induced mood symptoms in women with past perimenopausal depression. We focused on ER beta because the beta estrogen receptor is reported to mediate the effects of estradiol on the serotonergic system and mediate the antidepressant-like effects of estradiol in the forced-swim test. Moreover, selective agonists of estrogen receptor beta have been demonstrated to attenuate the behavioral and hypothalamic-pituitary-adrenal (HPA) axis response to stress. Our objective is to examine the specific role of estrogen receptor beta in the effects of estrogen withdrawal in women with a past perimenopause-related depression. Results of this study will determine the role of ER beta in estradiol withdrawal-induced mood symptoms and can provide preliminary data to support the efficacy and safety of this compound as a treatment for depression during the perimenopausal transition. STUDY POPULATION: Healthy, non-depressed postmenopausal women, ages 45 to 65, with a well-documented past perimenopause-related depression (within 12 years) and whose mood systems got better with estradiol DESIGN: The medication phase of this study is a seven-week randomized, double blind, placebo controlled study and there is a four week follow-up evaluation phase to monitor all women for the emergence of adverse effects post-medication exposure. Participants will have weekly outpatient visits, weekly blood draws and will also complete daily symptom rating scales. The study involves a three week baseline phase in which all women receive open label (OL) estradiol therapy (ET) at a dose of 100 micrograms per day by transdermal skin patch, after which all women receive three weeks of double blind (DB) medication (i.e., LY500307 \[at a daily dose of either 25 mg or 75 mg\] or placebo). All participants will receive three capsules of LY500307 or placebo each morning consisting of the following formulations: 1) women randomized to 75 mg LY500307 will receive three capsules each containing 25 mg LY500307; 2) women randomized to 25 mg LY500307 will receive one capsule containing 25 mg LY500307 and two capsules of placebo; and 3) women randomized to placebo will receive three capsules each containing placebo. Then, in non-menstruating women (i.e., the absence of reported menstrual bleeding of greater than 1-2 days during the double blind phase of this study), the double blind phase will be followed by one week of Provera to precipitate a progestin-induced menses. The week of Provera is not a research-related intervention but is clinically-indicated to induce endometrial shedding that will eliminate potentially abnormal endometrial tissue consequent to the three weeks of unopposed estradiol exposure.