The benefit of oestrogens and progestogens in postnatal depression

Estrogen administration and withdrawal in a model of hormone-simulated pregnancy lead to alterations in behavior and gene expression but do not induce depression-like phenotypes in mice

Pregnancy and the post-partum period are associated with substantial fluctuations in hormone levels and are frequently associated with significant stress. Many individuals also experience affective disturbances during the peri‑partum period, including anxiety, the 'baby blues,' and post-partum depression. However, the extent to which these affective changes result from rapidly altering hormone levels, increased stress, or the combination of both remains largely unknown. The current study sought to evaluate the consequences of pregnancy-like hormonal changes on behavior and gene expression in c57BL/6 mice in the absence of stress using a hormone-simulated pregnancy model. Our results reveal that animals receiving hormone injections to simulate the high levels of estrogen observed in late pregnancy and animals withdrawn from estrogen to mimic the rapid decline in this hormone following parturition both exhibit increased anxiety-like behavior compared to ovariectomized controls in the novel open field test. However, no other significant anxiety- or depression-like alterations were observed in either hormone-treated group compared to ovariectomized controls. Both hormone administration and estrogen withdrawal were shown to induce several significant alterations in gene expression in the bed nucleus of the stria terminalis and the paraventricular nucleus of the hypothalamus. In contrast to the estrogen withdrawal hypothesis of post-partum depression, our results suggest that this method estrogen withdrawal following hormone-simulated pregnancy in the absence of stress does not induce phenotypes consistent with post-partum depression in c57BL/6 mice. However, given that estrogen withdrawal does lead to significant gene expression changes in two stress-sensitive brain regions, it remains possible that estrogen withdrawal could still contribute to affective dysregulation in the peri-partum period by influencing susceptibility to stress. Future research is required to evaluate this possibility.

Progesterone, reproduction, and psychiatric illness

Mood and anxiety disorders are vastly overrepresented in women, and one important contributor to these differences is the fluctuation in sex steroids in women during the reproductive years. Considerable evidence supports a role for abnormal sensitivity to these hormonal fluctuations for some women, who develop mood symptoms associated with reproductive transitions. This chapter presents evidence of the role of endogenous progesterone and its metabolites in such mood symptoms, and then goes on to cover the evidence concerning exogenous progesterone's effects on mood. Overall, the literature does not support an association between exogenous progesterone and negative mood in the general population, but does indicate that subset of women may be vulnerable to such effects. Research is lacking on women with psychiatric illness.

Neuroprotection of reduced thyroid hormone with increased estrogen and progestogen in postpartum depression

Background: Postpartum depression (PPD) is a common serious mental health problem. Recent studies have demonstrated that hormone therapy serves as a promising therapeutic approach in managing PPD. The present study aims at exploring the role of thyroid hormone (TH), estrogen and progestogen in patients with PPD.Methods: Initially, PPD patients were enrolled and a PPD mouse model was established. The serum levels of estradiol (E2), progesterone (P), triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) were subsequently measured. Next, in order to identify the effects of TH, estrogen and progestogen on PPD progression, mice were administrated with E2, P, contraceptives (CA), Euthyrox and methimazole (MMI). Besides, the body weight, activities, basolateral amygdala (BLA) neuron cell structure and the related gene expression of mice were analyzed.Results: The PPD patients and the mice showed elevated serum levels of T3, T4, FT3 and FT4 along with diminished E2, P and TSH levels. In the mice administered with a combination of E2, P, and MMI, decreased TH and increased estrogen and progestogen were detected, which resulted in increased body weight, normal activities, and BLA neuron cell structure. Moreover, brain-derived neurotrophic factor (BDNF) and cAMP-responsive element-binding protein (CREB) were both up-regulated in PPD mice administrated with a combination of E2, P, and MMI, which was accompanied by decreased TH and elevated estrogen and progestogen.Conclusion: Taken together, reduced TH combined with enhanced estrogen and progestogen confers neuroprotection in PPD, highlighting a potential target in prevention and treatment of PPD.

Postpartum estrogen withdrawal impairs hippocampal neurogenesis and causes depression- and anxiety-like behaviors in mice

Postpartum estrogen withdrawal is known to be a particularly vulnerable time for depressive symptoms. Ovariectomized adult mice (OVX-mice) treated with hormone-simulated pregnancy (HSP mice) followed by a subsequent estradiol benzoate (EB) withdrawal (EW mice) exhibited depression- and anxiety-like behaviors, as assessed by forced swim, tail suspension and elevated plus-maze, while HSP mice, OVX mice or EB-treated OVX mice (OVX/EB mice) did not. The survival and neurite growth of newborn neurons in hippocampal dentate gyrus were examined on day 5 after EW. Compared with controls, the numbers of 28-day-old BrdU(+) and BrdU(+)/NeuN(+) cells were increased in HSP mice but significantly decreased in EW mice; the numbers of 10-day-old BrdU(+) cells were increased in HSP mice and OVX/EB mice; and the density of DCX(+) fibers was reduced in EW mice and OVX mice. The phosphorylation of hippocampal NMDA receptor (NMDAr) NR2B subunit or Src was increased in HSP mice but decreased in EW mice. NMDAr agonist NMDA prevented the loss of 28-day-old BrdU(+) cells and the depression- and anxiety-like behaviors in EW mice. NR2B inhibitor Ro25-6981 or Src inhibitor dasatinib caused depression- and anxiety-like behaviors in HSP mice with the reduction of 28-day-old BrdU(+) cells. The hippocampal BDNF levels were reduced in EW mice and OVX mice. TrkB receptor inhibitor K252a reduced the density of DCX(+) fibers in HSP mice without the reduction of 28-day-old BrdU(+) cells, or the production of affective disorder. Collectively, these results indicate that postpartum estrogen withdrawal impairs hippocampal neurogenesis in mice that show depression- and anxiety-like behaviors.

Tryptophan: the key to boosting brain serotonin synthesis in depressive illness

It has been proposed that focusing on brain serotonin synthesis can advance antidepressant drug development. Biochemical aspects of the serotonin deficiency in major depressive disorder (MDD) are discussed here in detail. The deficiency is caused by a decreased availability of the serotonin precursor tryptophan (Trp) to the brain. This decrease is caused by accelerated Trp degradation, most likely induced by enhancement of the hepatic enzyme tryptophan 2,3-dioxygenase (TDO) by glucocorticoids and/or catecholamines. Induction of the extrahepatic Trp-degrading enzyme indolylamine 2,3-dioxygenase (IDO) by the modest immune activation in MDD has not been demonstrated and, if it occurs, is unlikely to make a significant contribution. Liver TDO appears to be a target of many antidepressants, the mood stabilisers Li(+) and carbamazepine and possibly other adjuncts to antidepressant therapy. The poor, variable and modest antidepressant efficacy of Trp is due to accelerated hepatic Trp degradation, and efficacy can be restored or enhanced by combination with antidepressants or other existing or new TDO inhibitors. Enhancing Trp availability to the brain is thus the key to normalisation of serotonin synthesis and could form the basis for future antidepressant drug development.

Reproductive hormones and postpartum mood disturbances in Greek women

AIM

Postpartum mood disturbances are common among Greek women, with postpartum depression (PPD) being as high as 19%. This study aimed to investigate whether sex steroid hormone levels affect the incidence of postpartum mood disturbances.

MATERIALS AND METHODS

Fifty-seven women were evaluated for postpartum mood disturbances using the Postpartum Blues Questionnaire and the Edinburgh Postnatal Depression Scale on the 1st and 6th week. Serum estradiol, progesterone and testosterone concentrations were measured upon admission for delivery and daily until the fourth postpartum day. We then studied the association between hormone levels and the scores in the two psychometric scales.

RESULTS

Testosterone was the only hormone that was marginally associated with psychometric scoring in simple regression analysis. (Postpartum Blues during days 1-4: b = 4.291, 95% C.I. -0.796 to 9.377 and p-value = 0.096). Women with lower testosterone drops had higher scores in Postpartum Blues Questionnaire. This association, however, lost statistical significance in the multivariable analysis after adjusting for pregnancy duration. In multiple regression analysis, only pregnancy duration had the most constant adverse effect on psychometric scores: The shorter the duration of pregnancy, the higher the scores for Postpartum Blues. (r = -0.39, p < 0.01).

CONCLUSIONS

Our findings do not indicate an association between the occurrence of postpartum mood disorders and sex steroid hormone levels. Preterm labour may be associated with a higher risk of postpartum mood disturbances.

Neuroactive steroids in affective disorders: target for novel antidepressant or anxiolytic drugs?

In the past decades considerable evidence has emerged that so-called neuroactive steroids do not only act as transcriptional factors in the regulation of gene expression but may also alter neuronal excitability through interactions with specific neurotransmitter receptors such as the GABA(A) receptor. In particular, 3α-reduced neuroactive steroids such as allopregnanolone or allotetrahydrodeoxycorticosterone have been shown to act as positive allosteric modulators of the GABA(A) receptor and to play an important role in the pathophysiology of depression and anxiety. During depression, the concentrations of 3α,5α-tetrahydroprogesterone and 3α,5β-tetrahydroprogesterone are decreased, while the levels of 3β,5α-tetrahydroprogesterone, a stereoisomer of 3α,5α-tetrahydroprogesterone, which may act as an antagonist for GABAergic steroids, are increased. Antidepressant drugs such as selective serotonin reuptake inhibitors (SSRIs) or mirtazapine apparently have an impact on key enzymes of neurosteroidogenesis and have been shown to normalize the disequilibrium of neuroactive steroids in depression by increasing 3α-reduced pregnane steroids and decreasing 3β,5α-tetrahydroprogesterone. Moreover, 3α-reduced neuroactive steroids have been demonstrated to possess antidepressant- and anxiolytic-like effects both in animal and human studies for themselves. In addition, the translacator protein (18 kDa) (TSPO), previously called peripheral benzodiazepine receptor, is the key element of the mitochondrial import machinery supplying the substrate cholesterol to the first steroidogenic enzyme (P450scc), which transforms cholesterol into pregnenolone, the precursor of all neurosteroids. TSPO ligands increase neurosteroidogenesis and are a target of novel anxiolytic drugs producing anxiolytic effects without causing the side effects normally associated with conventional benzodiazepines such as sedation or tolerance. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain.

Effect of depot medroxyprogesterone acetate on postpartum depression

BACKGROUND

Depot medroxyprogesterone acetate (DMPA) is commonly prescribed to women immediately postpartum due to its efficacy, convenience and lack of estrogen. It is unclear whether administering a progestin injection can affect the course of postpartum depression (PPD), which some suspect to be influenced by hormonal changes. In this retrospective study, the objective was to determine whether DMPA administered immediately postpartum influences the development of PPD.

STUDY DESIGN

A retrospective review of a total of 404 charts was conducted of clinic patients who were scheduled for 6-week postpartum visits at a major medical center, where all patients are routinely asked to complete the Edinburgh Postnatal Depression Scale (EPDS). The average scores on the EPDS at these visits were compared between patients who had received DMPA prior to postpartum discharge from the hospital and patients who had not received any hormonal contraception by using an unpaired t test. In addition, the proportions of women diagnosed with PPD via the scale were compared via contingency tables.

RESULTS

Fifty-five women who had received immediate DMPA were compared with 192 women with no hormonal contraception after delivery. The groups were similar in parity, race, mode of delivery and weight, but women receiving DMPA were significantly younger (24.2 vs. 26.2 years, p=.03). Mean EPDS scores at 6 weeks postpartum were not statistically significant between the groups (5.02 vs. 6.17, p=.16). Six patients (10.9%) who received immediate DMPA were diagnosed with PPD based on EPDS scores greater than or equal to 13, while 27 (14.1%) in the comparison group had PPD (p=.88).

CONCLUSION

Administration of DMPA in the immediate postpartum period does not appear to predispose women to PPD.

Regulation of anxiety during the postpartum period

Healthy mother-infant interactions are critical for the physical, cognitive, and psychological development of offspring. Such interactions rely on numerous factors, including a positive maternal emotional state. However, many postpartum women experience emotional dysregulation, often involving elevated anxiety. Neuroendocrine factors contributing to the onset of postpartum anxiety symptoms are mostly unknown, but irregularities in hypothalamic-pituitary-adrenal axis function, reduced prolactin and oxytocin signaling, or parturitional withdrawal of ovarian, placental and neural steroids could contribute to anxiety in susceptible women. Although the causes of initial onset are unclear, postpartum anxiety can be mitigated by recent contact with infants. Numerous neurochemical systems, including oxytocin, prolactin, GABA, and norepinephrine mediate this anxiolytic effect of infant contact. Insight into the etiology of postpartum anxiety disorders, and how contact with infants helps counter existing anxiety dysregulation, will surely facilitate the diagnosis and treatment of postpartum women at risk for, or experiencing, an anxiety disorder.

Women's Mental Health Research: The Emergence of a Biomedical Field

This review surveys the field of women's mental health, with particular emphasis on its evolution into a distinct area of biomedical research. The field employs a biomedical disease model but it also emphasizes social and cultural influences on health outcomes. In recent years, its scope has expanded beyond studies of disorders occurring in women at times of reproductive transitions and it now encompasses a broader study of sex and gender differences. Historical and conceptual influences on the field are discussed. The review also surveys gender differences in the prevalence and clinical manifestations of mental disorders. Epidemiological findings have provided a rich resource for theory development, but without research tools to test theories adequately, findings of gender differences have begged the question of their biological, social, and cultural origins. Clinical depression is used to exemplify the usefulness of a sex/gender perspective in understanding mental illness; and major theories proposed to account for gender differences are critically evaluated. The National Institutes of Health (NIH) is the primary federal funding source for biomedical women's mental health research. The review surveys areas of emphasis in women's mental health research at the NIH as well as some collaborative activities that represent efforts to translate research findings into the public health and services arenas. As new analytic methods become available, it is anticipated that a more fundamental understanding of the biological and behavioral mechanisms underlying sex and gender differences in mental illness will emerge. Nonetheless, it is also likely that integration of findings predicated on different conceptual models of the nature and causes of mental illness will remain a challenge. These issues are discussed with reference to their impact on the field of women's mental health research.

The role of estrogen therapy in postpartum psychiatric disorders: an update

OBJECTIVES

The aim of this review is to assess and summarize the existing literature data about the efficacy of estrogen replacement therapy (ERT) in preventing and treating postpartum psychiatric disorders.

METHODS

An extensive and unrestrictive computerized search (from 1970 to June 2005) on MEDLINE/PubMed, TOXNET, EMBASE, and Cochrane Databases was conducted with the following search terms: estradiol, estrogen-treatment, hormonal treatment, therapy, postpartum depression, postnatal depression, puerperal depression, postpartum blues, postpartum psychosis, lactation, and breastfeeding.

RESULTS

In assessing available literature information about the role of ERT in preventing and treating puerperal psychiatric diseases, all reviewed studies were found to suffer from severe methodological limitations.

CONCLUSION

Well-designed and strictly focused multicenter trials are warranted in order to firmly establish the effectiveness of ERT in puerperal psychiatric disorders.

A study of Welsh mothers' experiences of postnatal depression

OBJECTIVE

to examine the experiences of Welsh mothers diagnosed with postnatal depression and to question whether postnatal depression is socially determined.

DESIGN

qualitative interviews using a semi-structured questionnaire to clarify mothers' thoughts and feelings within the postnatal period.

SETTING

a semi-rural part of south-west Wales, previously dominated by the mining industry.

PARTICIPANTS

ten mothers with one or more children participated in the study. Most of the mothers were from lower socio-economic groups. They were selected from 30 women diagnosed with postnatal depression.

FINDINGS

mothers had little knowledge of the effects of postnatal depression before becoming pregnant, and were initially reluctant to confide or share their feelings. Economic pressures determined a second income and necessitated mothers returning to work. This left them with little quality time for their babies and family. The prime support networks, which in previous generations were grandmothers, were absent, and mothers relied on social services and voluntary support groups.

IMPLICATIONS FOR PRACTICE

a greater understanding of the emotional and social effects of childbirth may help mothers to avoid feelings of isolation and the inability to cope. Discussing the issues of socio-emotional strain during pregnancy may help the mother to recognise the symptoms that identify postnatal depression, legitimise the condition and begin the recovery process.

Preventing postpartum depression part I: a review of biological interventions

OBJECTIVE

This paper critically reviews the literature to determine the current state of scientific knowledge concerning the prevention of postpartum depression (PPD) from a biological perspective.

METHODS

The criteria used to evaluate the interventions were derived from the standardized methodology developed by the Canadian Task Force on Preventive Health Care. Databases searched for this review include Medline, PubMed, Cinahl, PsycINFO, Embase, ProQuest, the Cochrane Library, and the World Health Organization Reproductive Health Library. Studies selected were peer-reviewed English-language articles published between January 1, 1966, and December 31, 2003.

RESULTS

Seven studies that met criteria were examined. These studies focused on evaluating the preventive effect of antidepressant medication, estrogen and progesterone therapy, thyroid therapy, docosahexanoic acid, and calcium supplementation. Although some of these interventions have been examined rigorously for depression unrelated to childbirth, methodological study limitations render intervention efficacy equivocal for PPD; thus, there is limited strong evidence to guide practice or policy recommendations.

CONCLUSIONS

Despite the recent upsurge of interest in this area, many questions remain unanswered, which has several implications for research.