Effects of 3B-diol on depression during perimenopause: behavioral and neurogenesis assessment

• Grant number: 18/00535-5
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2018
• End date: November 30, 2020
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Janete Aparecida Anselmo Franci
• Grantee: Janete Aparecida Anselmo Franci
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated scholarship(s): 18/14336-4 - Effects of 3B-diol on depression during perimenopause: behavioral and neurogenesis assessment., BP.TT

Abstract

Perimenopause, the period of transition from reproductive to non-reproductive life, is the period of greater vulnerability of women to depression. There is no consensus on a possible correlation between depression and hormonal changes at this time, but most authors did not find a correlation with estrogen plasma concentrations. In fact, despite the fluctuation of these hormone levels, mean plasma concentrations in perimenopause are not different from those in premenopausal women.Despite this, the literature shows that oestradiol therapy improves many symptoms of perimenopause, an effect not yet understood since women do not present estrogen deficiency in this period. In an animal model of perimenopause (rat), we observed depression-like behaviors, which were prevented by estrogen therapy. In later studies, we observed that although estradiol levels are normal in periestropausal rats, the expression of estradiol receptors (ER)beta is greatly reduced in the dorsal nucleus of the raphe (DRN) which has been corrected by estradiol. Thus, although estrogens are at normal levels in theperiestropause, the estradiol sensitivity of central areas associated with mood disorders is decreased. The increased ER beta expression induced by estradiol in the DRN facilitated the action of this hormone in this nucleus and increased the number of serotonergic cells, thus increasing serotonin content in the hippocampus. The expression of ER beta in the hippocampus also was increased by estradiol. Despite all these benefic effects, estrogen therapy causes dangerous side effects to women's health, such as breast and endometrial cancer due to the activation of receptors alpha for estradiol. Thus, therapy with specific ER beta agonists, such as the 3 beta-diol proposed in the present project, would have dual advantage: to treat the symptoms ofperimenopause and to eliminate side effects. Current evidence indicates that adult hippocampal neurogenesis is necessary forsuccessful antidepressant action. The neurogenic hypothesis postulates that a decrease in hippocampal neurons is correlatedwith the pathogenesis and pathophysiology of depression and it is known that increased neurogenesis is necessary for the treatment of depression and is also a classic effect of estrogens. Thus, the aim of this study is to evaluate in a perimenopause animal model (female rat) whether ER beta selective agonist therapy, 3 beta-diol: 1) prevents perimenopausal depression (by forced swimming test),2) increases production of new neurons (by icc for KI-67) and / or increases neuronal survival (by icc for DCX) of the hippocampusand 3) increases the function (by icc for TPH), proliferation (KI-67), and / or the survival (DCX) of the serotonergic neurons of the DRN. If the hypothesis of preventing depression is confirmed, an important opportunity can be created for the hormonal therapy of women with a family history of breast or endometrial cancer and who exhibit mood changes during perimenopause. (AU)