Role of mother’s genes and environment in postpartum depression. Proc Natl Acad Sci U S A. 2011;108:8189-8193. [PMID: 21576482 DOI: 10.1073/pnas.1014129108]

Postpartum Depression: A Clinical Review of Impact and Current Treatment Solutions

Depression during the first year postpartum (postpartum depression) impacts millions of women and their families worldwide. In this narrative review, we provide a summary of postpartum depression, examining the etiology and consequences, pharmacological and psychological treatments, and potential mechanisms of change and current barriers to care. Psychological treatments are effective and preferred by many perinatal patients over medications, but they often remain inaccessible. Key potential mechanisms underlying their effectiveness include treatment variables (e.g., dosage and therapeutic alliance) and patient behaviors (e.g., activation and avoidance and emotional regulation). Among pharmacological treatments, the selective serotonin reuptake inhibitor (SSRI) sertraline is generally the first-line antidepressant medication recommended to women in the postpartum period due to its minimal passage into breastmilk and the corresponding decades of safety data. Importantly, most antidepressant drugs are considered compatible with breastfeeding. Neurosteroids are emerging as an effective treatment for postpartum depression, although currently this treatment is not widely available. Barriers to widespread access to treatment include those that are systematic (e.g., lack of specialist providers), provider-driven (e.g., lack of flexibility in treatment delivery), and patient-driven (e.g., stigma and lack of time for treatment engagement). We propose virtual care, task-sharing to non-specialist treatment providers, and collaborative care models as potential solutions to enhance the reach and scalability of effective treatments to address the growing burden of postpartum depression worldwide and its negative impact on families and society.

Potential therapeutic effects of Chinese herbal medicine in postpartum depression: Mechanisms and future directions

ETHNOPHARMACOLOGICAL RELEVANCE

Postpartum depression (PPD) is a common psychiatric disorder in women after childbirth. Per data from epidemiologic studies, PPD affects about 5%-26.32% of postpartum mothers worldwide. Biological factors underlying this condition are multiple and complex and have received extensive inquiries for the roles they play in PPD. Chinese herbal medicine (CHM), which is widely used as a complementary and alternative therapy for neurological disorders, possesses multi-component, multi-target, multi-access, and low side effect therapeutic characteristics. CHM has already shown efficacy in the treatment of PPD, and a lot more research exploring the mechanisms of its potential therapeutic effects is being conducted.

AIM OF THE REVIEW

This review provides an in-depth and comprehensive overview of the underlying mechanisms of PPD, as well as samples the progress made in researching the potential role of CHM in treating the disorder.

MATERIALS AND METHODS

Literature was searched comprehensively in scholarly electronic databases, including PubMed, Web of Science, Scopus, CNKI and WanFang DATA, using the search terms "postpartum depression", "genetic", "hormone", "immune", "neuroinflammation", "inflammation", "neurotransmitter", "neurogenesis", "brain-gut axis", "traditional Chinese medicine", "Chinese herbal medicine", "herb", and an assorted combination of these terms.

RESULTS

PPD is closely associated with genetics, as well as with the hormones, immune inflammatory, and neurotransmitter systems, neurogenesis, and gut microbes, and these biological factors often interact and work together to cause PPD. For example, inflammatory factors could suppress the production of the neurotransmitter serotonin by inducing the regulation of tryptophan-kynurenine in the direction of neurotoxicity. Many CHM constituents improve anxiety- and depression-like behaviors by interfering with the above-mentioned mechanisms and have shown decent efficacy clinically against PPD. For example, Shen-Qi-Jie-Yu-Fang invigorates the neuroendocrine system by boosting the hormone levels of hypothalamic pituitary adrenal (HPA) and hypothalamic pituitary gonadal (HPG) axes, regulating the imbalance of Treg/T-helper cells (Th) 17 and Th1/Th2, and modulating neurotransmitter system to play antidepressant roles. The Shenguiren Mixture interferes with the extracellular signal-regulated kinase (ERK) pathway to enhance the number, morphology and apoptosis of neurons in the hippocampus of PPD rats. Other herbal extracts and active ingredients of CHM, such as Paeoniflorin, hypericin, timosaponin B-III and more, also manage depression by remedying the neuroendocrine system and reducing neuroinflammation.

CONCLUSIONS

The pathogenesis of PPD is complex and diverse, with the main pathogenesis not clear. Still, CHM constituents, like Shen-Qi-Jie-Yu-Fang, the Shenguiren Mixture, Paeoniflorin, hypericin and other Chinese Medicinal Formulae, active monomers and Crude extracts, treats PPD through multifaceted interventions. Therefore, developing more CHM components for the treatment of PPD is an essential step forward.

Linked emergence of racial disparities in mental health and epigenetic biological aging across childhood and adolescence

Marginalization due to structural racism may confer an increased risk for aging-related diseases - in part - via effects on people's mental health. Here we leverage a prospective birth cohort study to examine whether the emergence of racial disparities in mental health and DNA-methylation measures of biological aging (i.e., DunedinPACE, GrimAge Acceleration, PhenoAge Acceleration) are linked across childhood and adolescence. We further consider to what extent racial disparities are statistically accounted for by perinatal and postnatal factors in preregistered analyses of N=4,898 participants from the Future of Families & Child Wellbeing Study, of which N=2,039 had repeated saliva DNA methylation at ages 9 and 15 years. We find that racially marginalized children had higher levels of externalizing and internalizing behaviors and diverging longitudinal internalizing slopes. Black compared to White identifying children, children living in more racially segregated neighborhoods, and racially marginalized children more affected by colorism tended to have higher age-9 levels of biological aging and more biological age acceleration over adolescence. Notably, longitudinal increases in internalizing and externalizing behavior were correlated with longitudinal increases in biological aging. While racial and ethnic disparities in mental health were largely statistically accounted for by socioeconomic variables, racial differences in biological aging were often still visible beyond covariate controls. Our findings indicate that racial disparities in mental health and biological aging are linked and emerge early in life. Programs promoting racial health equity must address the psychological and physical impacts of structural racism in children. Comprehensive measures of racism are lacking in current population cohorts.

Overview of metabolomic aspects in postpartum depression

Along with the typical biochemical alterations that occur during pregnancy, certain metabolic changes might be associated with the development of several psychiatric disorders, including postpartum depression (PPD), which is the most common type of psychiatric disorder during pregnancy or first postpartum year, and it develops in about 15% of women. Metabolomics is a rapidly developing discipline that deals with the metabolites as the final products of all genetically controlled biochemical pathways, highly influenced by external and internal changes. The aim of this paper was to review the published studies whose results suggest or deny a possible association between the fine regulation of the metabolome and PPD, enabling conclusions about whether metabolomics could be a useful tool in defining the biochemical pathways directly involved in the etiology, diagnosis and course of PPD. Beside numerous hormonal changes, a lot of different metabolic pathways have been discovered to be affected in women with PPD or associated with its development, including alterations in the energy metabolism, tryptophan and amino acid metabolism, steroid metabolism, purine cycle, as well as neurotransmitter metabolism. Additionally, metabolomics helped in defining the association between PPD and the exposure to various endocrine disrupting metabolites during pregnancy. Finally, metabolome reflects different PPD therapies and exposure of fetus or breastfed infants to pharmacotherapy prescribed to a mother suffering from PPD. This review can help in creating the picture about metabolomics' broad application in PPD studies, but it also implies that its potential is still not completely used.

Genetic predictors of cultural values variation between societies

Associations between the STin2 and 5-HTTLPR polymorphisms within the serotonin transporter gene, SLC6A4, and culture across societies were examined. Based on an analysis of 75 primary studies (28,726 individuals), STin2 allelic frequencies were found to vary widely across countries, ranging from 26% in Germany to 85% in Singapore. Across 53 countries, and after controlling for all major environmental influences of culture, STin2 and 5-HTTLPR were found to explain 23.6% unique variance in monumentalism but none in individualism. Our findings evidence a significant role of genetics in predicting cross-societal cultural values variation, and potentially speak to the need for and importance of incorporating both nature and nurture in theories of cultural values variation across societies.

Association of polymorphisms of calcium reabsorption genes SLC12A1, KCNJ1 and SLC8A1 with colorectal adenoma

BACKGROUND

In recent years, morbidity and mortality from colorectal cancer have increased. Colorectal adenoma is the main precancerous lesion. Understanding the pathogenesis of colorectal adenoma will help to improve the early diagnosis rate of colorectal cancer.

METHODS

In this case-control study, we focused on three single nucleotide polymorphisms (SNPs) in genes SLC8A1 (rs4952490), KCNJ1 (rs2855798), and SLC12A1 (rs1531916). We analyzed 207 colorectal adenoma patients (112 high-risk cases and 95 low-risk cases) and 212 control subjects by Sanger sequencing. A food frequency questionnaire (FFQ) was used to survey demographic characteristics and dietary nutrition.

RESULTS

In the overall analysis, the results suggested that the AA+AG and AG genotype carriers of rs4952490 had a 73.1% and 78% lower risk of colorectal adenoma compared to GG genotype carriers, respectively. However rs2855798 and rs1531916 were not associated with the incidence of colorectal adenoma. Additionally, stratified analysis showed that rs4952490 AA+AG and AG genotypes had a protective effect against low-risk colorectal adenoma in patients aged ≤ 60 years old who were non-smokers. We also observed that when calcium intake was higher than 616 mg/d and patients carried at least one gene with variant alleles there was a protective effect against low-risk colorectal adenoma.

CONCLUSIONS

Interactions between dietary calcium intake and calcium reabsorption genes may affect the occurrence and development of colorectal adenoma.

Risk Factors for Postpartum Depression Based on Genetic and Epigenetic Interactions

Postpartum depression (PPD) is a serious mood disorder that tends to occur after the delivery, which may bring lifelong consequences to women and their families in terms of family relationships, social relationships, and mental health. Currently, various risk factors including environmental factors and genetic factors that may induce postpartum depression have been extensively studied. In this review, we suggest that postpartum women's susceptibility to postpartum depression may be the result of the interaction between the genes associated with postpartum depression as well as the interaction between genetic and environmental factors. We reviewed the genes that have been studied in postpartum depression, including genes related to the synthesis, metabolism, and transport of monoamine neurotransmitters, key molecules of the HPA axis, and the kynurenine pathway. These studies have found more or less gene-gene and gene-environment interactions, so we will discuss these issues in more detail. However, so far, the conclusions of these risk factors, especially genetic factors, are not completely consistent in the occurrence and exacerbation of symptoms in postpartum depression, and it is not clear how these risk factors specifically participate in the pathological mechanism of the disease and play a role. We conclude that the role of genetic polymorphisms, including genetic and epigenetic processes, in the occurrence and development of postpartum depression, is complex and ambiguous. We also note that interactions between multiple candidate genes and the environment have been suggested as causes of depression, suggesting that more definitive research is needed to understand the heritability and susceptibility of PPD. Overall, our work supports the hypothesis that postpartum depression is more likely to be caused by a combination of multiple genetic and environmental factors than by a single genetic or environmental influence.

Cortical and subcortical morphological alterations in postpartum depression

Postpartum depression (PPD) is the most common postpartum psychiatric disorder, which can negatively affect both mothers and their offspring. Although the functional changes of PPD have been extensively studied, little is known about its structural abnormalities. This study aimed to examine the cortical and subcortical morphological abnormalities in PPD. High resolution T1 structural MRI data of 29 PPD women and 23 matched healthy postpartum women (HPW) were included in this study. Using surface-based morphometry, we examined the differences between the PPD and HPW group in the cortical thickness, local gyrification index and shape changes of deep gray matter nuclei. Compared with the HPW group, women with PPD showed significantly increased cortical thickness in the left superior frontal gyrus, cuneus and right lingual gyrus and fusiform gyrus, which correlated marginally with the EPDS scores of these subjects. In addition, women with PPD showed significant regional inflation in the right pallidum compared with the HPW group. These findings provided further evidence for the structural brain abnormalities in PPD.

Post-partum depression: From clinical understanding to preclinical assessments

Post-partum depression (PPD) with varying clinical manifestations affecting new parents remains underdiagnosed and poorly treated. This minireview revisits the pharmacotherapy, and relevant etiological basis, capable of advancing preclinical research frameworks. Maternal tasks accompanied by numerous behavioral readouts demand modeling different paradigms that reflect the complex and heterogenous nature of PPD. Hence, effective PPD-like characterization in animals towards the discovery of pharmacological intervention demands research that deepens our understanding of the roles of hormonal and non-hormonal components and mediators of this psychiatric disorder.

Genetic variants in the genes of the sex steroid hormone metabolism and depressive symptoms during and after pregnancy

PURPOSE

The aim of this study was to conduct an association analysis of depressive symptoms and polymorphisms in the ESR1, PGR, CYP19A1, and COMT genes in pregnant and postpartum women.

METHODS

The Franconian Maternal Health Evaluation Study (FRAMES) recruited healthy pregnant women prospectively for assessment of maternal and fetal health. The German version of the 10-item Edinburgh Postnatal Depression Scale (EPDS) was completed at three time points in this prospective cohort study. Visit 1 was at study entry in the third trimester of pregnancy, visit 2 was shortly after birth, and visit 3 was 6-8 months after birth. Germline DNA and depression measurements from 361 pregnant women were available for analysis. Six single nucleotide polymorphisms (SNPs) in the above-mentioned genes were genotyped. After reconstruction of haplotypes for PGR (rs1042838 and rs10895068) and CYP19A1 (rs10046 and rs4646), a multifactorial linear mixed model was applied to the data to describe the association between haplotypes and depression values. The single SNPs for ESR1 (rs488133) and COMT (rs4680) were analyzed separately using linear mixed models analogously.

RESULTS

The mean antepartum EPDS measurement was 5.1, the mean postpartal measurement after 48-72 h was 3.5, and the mean value 6-8 months postpartum was 4.2. The SNPs in PGR were reconstructed into three haplotypes. The most common haplotype was GG, with 63.43% of patients carrying two copies and 33.52% carrying one copy. For haplotype GA, the group of carriers of two copies (0.28%) was combined with the carriers of one copy (9.70%). Haplotype reconstruction using CYP19A1 SNPs resulted in three haplotypes. The most common haplotype was TC, with 25.48% of patients carrying two copies and 51.52% one copy. None of the haplotype blocks and neither of the two single SNPs showed any significant associations with EPDS values.

CONCLUSIONS

The candidate haplotypes analyzed in PGR and CYP19A1 and single SNPs in ESR1 and COMT did not show any association with depression scores as assessed by EPDS in this cohort of healthy unselected pregnant women.

A neural model of vulnerability and resilience to stress-related disorders linked to differential susceptibility

Expert opinion remains divided concerning the impact of putative risk factors on vulnerability to depression and other stress-related disorders. A large body of literature has investigated gene by environment interactions, particularly between the serotonin transporter polymorphism (5-HTTLPR) and negative environments, on the risk for depression. However, fewer studies have simultaneously investigated the outcomes in both negative and positive environments, which could explain some of the inconclusive findings. This is embodied by the concept of differential susceptibility, i.e., the idea that certain common gene polymorphisms, prenatal factors, and traits make some individuals not only disproportionately more susceptible and responsive to negative, vulnerability-promoting environments, but also more sensitive and responsive to positive, resilience-enhancing environmental conditions. Although this concept from the field of developmental psychology is well accepted and supported by behavioral findings, it is striking that its implementation in neuropsychiatric research is limited and that underlying neural mechanisms are virtually unknown. Based on neuroimaging studies that examined how factors mediating differential susceptibility affect brain function, we posit that environmental sensitivity manifests in increased salience network activity, increased salience and default mode network connectivity, and increased salience and central executive network connectivity. These changes in network function may bring about automatic exogenous attention for positive and negative stimuli and flexible attentional set-shifting. We conclude with a call to action; unraveling the neural mechanisms through which differential susceptibility factors mediate vulnerability and resilience may lead us to personalized preventive interventions.

Short-term oestrogen as a strategy to prevent postpartum depression in high-risk women: protocol for the double-blind, randomised, placebo-controlled MAMA clinical trial

INTRODUCTION

Postpartum depression affects 10%-15% of women and has a recurrence rate of 40% in subsequent pregnancies. Women who develop postpartum depression are suspected to be more sensitive to the rapid and large fluctuations in sex steroid hormones, particularly estradiol, during pregnancy and postpartum. This trial aims to evaluate the preventive effect of 3 weeks transdermal estradiol treatment immediately postpartum on depressive episodes in women at high risk for developing postpartum depression.

METHODS AND ANALYSIS

The Maternal Mental Health Trial is a double-blind, randomised and placebo-controlled clinical trial. The trial involves three departments of obstetrics organised under Copenhagen University Hospital in Denmark. Women who are singleton pregnant with a history of perinatal depression are eligible to participate. Participants will be randomised to receive either transdermal estradiol patches (200 µg/day) or placebo patches for 3 weeks immediately postpartum. The primary outcome is clinical depression, according to the Diagnostic and Statistical Manual of Mental Disorders-V criteria of Major Depressive Disorder with onset at any time between 0 and 6 months postpartum. Secondary outcomes include, but are not limited to, symptoms of depression postpartum, exclusive breastfeeding, cortisol dynamics, maternal distress sensitivity and cognitive function. The primary statistical analysis will be performed based on the intention-to-treat principle. With the inclusion of 220 participants and a 20% expected dropout rate, we anticipate 80% power to detect a 50% reduction in postpartum depressive episodes while controlling the type 1 error at 5%.

ETHICS AND DISSEMINATION

The study protocol is approved by the Regional Committees on Health Research Ethics in the Capital Region of Denmark, the Danish Medicines Agency and the Centre for Data Protection Compliance in the Capital Region of Denmark. We will present results at scientific meetings and in peer-reviewed journals and in other formats to engage policymakers and the public.

TRIAL REGISTRATION NUMBER

NCT04685148.

Neurobiology of peripartum mental illness

At least one in seven pregnant or recently postpartum women will experience a mental illness such as an anxiety disorder, depressive disorder, or substance use disorder. These mental illnesses have detrimental effects on the health of the mother, child, and family, but little is known about the hypothalamic and other neural correlates of maternal mental health concerns. The transition to parenthood alone is a time of remarkable neural plasticity, so it is perhaps not surprising that current research is showing that maternal mental illness has unique neural profiles. Furthermore, the neural systems affected by peripartum mental illness overlap and interact with the systems involved in maternal caregiving behaviors, and mother-infant interactions are, therefore, highly susceptible to disruption. This review discusses what we know about the unique neural changes occurring during peripartum mental illness and the role of the hypothalamus in these illnesses. With an improved understanding of the neural correlates of maternal mental health and disease, we will be better equipped to predict risk, develop effective treatments, and ultimately prevent suffering for millions of parents during this critical time in life.

Enrichment Environment Positively Influences Depression- and Anxiety-Like Behavior in Serotonin Transporter Knockout Rats through the Modulation of Neuroplasticity, Spine, and GABAergic Markers

The serotonin transporter (5-HTT in humans, SERT in rodents) is the main regulator of serotonergic transmission in the brain. The short allelic variant of the 5-HTT gene is in humans associated with psychopathologies and may enhance the vulnerability to develop depression after exposure to stressful events. Interestingly, the short allele also increases the sensitivity to a positive environment, which may buffer the vulnerability to depression. Since this polymorphism does not exist in rodents, male SERT knockout (SERT^−/−) rats were tested to explore the molecular mechanisms based on this increased predisposition. This article investigates the influences of a positive manipulation, namely, enriched environment (EE), on the depressive-like behavior observed in SERT^−/− rats. We found that one month of EE exposure normalized the anhedonic and anxious-like phenotype characteristics of this animal model. Moreover, we observed that EE exposure also restored the molecular alterations in the prefrontal cortex by positively modulating the expression of the neurotrophin Bdnf, and of spines and gamma-aminobutyric acid (GABA)ergic markers. Overall, our data confirm the depression-like phenotype of SERT^−/− rats and highlight the ability of EE to restore behavioral and molecular alterations, thus promoting the opportunity to use EE as a supporting non-pharmacological approach to treat mood disorders.

The study protocol: Neuroendocrinology and (epi-) genetics of female reproductive transition phase mood disorder - an observational, longitudinal study from pregnancy to postpartum

BACKGROUND

Postpartum depression is considered to be one of the most common health threats during pregnancy and postpartum, affecting not only the woman herself but also the offspring and the whole family system. Evidence for a conclusive etiopathological model with distinct risk and resilience factors is still broadly lacking. Therefore, the aim of the present study is to investigate numerous health-related markers to obtain greater insight into which biopsychosocial profiles render women more vulnerable to PPD or facilitate a healthy transition from pregnancy to postpartum.

METHODS

The observational, longitudinal study aims to include a total of 288 physically healthy women, aged 20-45 years. A multitude of relevant parameters, of an (epi-) genetic, endocrinological, physiological and psychological nature, will be assessed over a period of 5 months, following the participants from the 3rd trimester until three months postpartum.

DISCUSSION

The ultimate goal of the present study is to ameliorate mental health care during pregnancy and postpartum, by gaining a better understanding of the underlying biopsychosocial mechanisms that women undergo during the transition from pregnancy to postpartum.

Is Postpartum Depression Different From Depression Occurring Outside of the Perinatal Period? A Review of the Evidence

Whether a major depressive episode occurring in the postpartum period (i.e., postpartum depression [PPD]) is sufficiently distinct from major depressive episodes occurring at other times (i.e., major depressive disorder) to warrant a separate diagnosis is a point of debate with substantial clinical significance. The evidence for and against diagnostic distinction for PPD is reviewed with respect to epidemiology, etiology, and treatment. Overall, evidence that PPD is distinct from major depressive disorder is mixed and is largely affected by how the postpartum period is defined. For depression occurring in the early postpartum period (variably defined, but typically with onset in the first 8 weeks), symptom severity, heritability, and epigenetic data suggest that PPD may be distinct, whereas depression occurring in the later postpartum period may be more similar to major depressive disorder occurring outside of the perinatal period. The clinical significance of this debate is considerable given that PPD, the most common complication of childbirth, is associated with immediate and enduring adverse effects on maternal and offspring morbidity and mortality. Future research investigating the distinctiveness of PPD from major depressive disorder in general should focus on the early postpartum period when the rapid decline in hormones contributes to a withdrawal state, requiring profound adjustments in central nervous system function.

A systematic review investigating if genetic or epigenetic markers are associated with postnatal depression

BACKGROUND

Postnatal depression (PND) is common, affects the health of the mother, the development of the infant and places a large financial burden on services. Genetic and epigenetic biomarkers for PND could potentially improve the accuracy of current antenatal screening approaches. The aim of this systematic review is to report on the evidence for an association between genetic or epigenetic factors and postnatal depression.

METHOD

A systematic search of five databases (Medline, EMBASE, PILOT, PsychINFO and SCOPUS) was carried out using the following (MeSh) terms and keywords: postpartum, depression, postnatal depression, genetics, genetic polymorphisms and epigenetics. Inclusion criteria were applied and quality of studies was assessed using guidelines from the HuGE Review Handbook (Little and Higgins, 2006).

RESULTS

Following removal of duplicate articles, 543 remained; of these 37 met the inclusion criteria. Positive associations have been reported between PND and polymorphisms in the HMNC1, COMT, MAOT, PRKCB, ESR1, SLC6A4 genes in the presence of stressful life events, the BDNF gene when the postnatal period occurs during autumn and winter months and the OXT and OXTR genes in the presence of childhood adversity experienced by the mother. Epigenetic interactions with genotype, estrogen, and childhood adversity were identified that are predictive of PND.

LIMITATIONS

The number of studies investigating some of the markers was small and grey literature was not included.

CONCLUSION

This review highlights the importance of examining the interaction between epigenetic, genetic, hormonal and environmental factors in order to fully understand the risk factors for PND and to improve the accuracy of current antenatal and early postnatal screening procedures. Women susceptible to PND appear to have heightened epigenetic sensitivity to the physiological changes of childbirth or to environmental factors conferred by genotype.

Perinatal depression and infant mental health

A mother's mental health during pregnancy and the first year postpartum is of the utmost importance to the cognitive, social, and emotional development of her child. Perinatal depression is associated with increased risk for wide-ranging adverse child development effects that can affect infant and early childhood mental health. Although effective treatments for perinatal depression exist, it is currently unclear if treatment of maternal depression alone is sufficient to ameliorate the negative effects of maternal depression on child outcomes. Interventions focused on the mother-infant relationship and dyadic interaction may be required to address the potential effect of maternal depression on the child. This paper provides an overview of maternal perinatal depression, the risk it poses for infant/early-childhood mental health, strategies for intervention that include mitigating depression and decreasing risk to the child, and implications for psychiatric nurses who work with perinatal women. Early identification and treatment of perinatal depression are critical to ensure optimal infant development and the child's future mental health.

Serotonin and motherhood: From molecules to mood

Emerging research points to a valuable role of the monoamine neurotransmitter, serotonin, in the display of maternal behaviors and reproduction-associated plasticity in the maternal brain. Serotonin is also implicated in the pathophysiology of numerous affective disorders and likely plays an important role in the pathophysiology of maternal mental illness. Therefore, the main goals of this review are to detail: (1) how the serotonin system of the female brain changes across pregnancy and postpartum; (2) the role of the central serotonergic system in maternal caregiving and maternal aggression; and (3) how the serotonin system and selective serotonin reuptake inhibitor medications (SSRIs) are involved in the treatment of maternal mental illness. Although there is much work to be done, studying the central serotonin system's multifaceted role in the maternal brain is vital to our understanding of the processes governing matrescence and the maintenance of motherhood.

The dynamic serotonin system of the maternal brain

Many pregnant and postpartum women worldwide suffer from high anxiety and/or depression, which can have detrimental effects on maternal and infant well-being. The first-line pharmacotherapies for prepartum and postpartum affective disorders continue to be the selective serotonin reuptake inhibitors (SSRIs), despite the lack of large well-controlled studies demonstrating their efficacy in reproducing women and the potential for fetal/neonatal exposure to the drugs. Prepartum or postpartum use of SSRIs or other drugs that modulate the brain's serotonin system is also troubling because very little is known about the typical, let alone the atypical, changes that occur in the female central serotonin system across reproduction. We do know from a handful of studies of women and female laboratory rodents that numerous aspects of the central serotonin system are naturally dynamic across reproduction and are also affected by pregnancy stress (a major predisposing factor for maternal psychopathology). Thus, it should not be assumed that the maternal central serotonin system being targeted by SSRIs is identical to non-parous females or males. More information about the normative and stress-derailed changes in the maternal central serotonin system is essential for understanding how serotonin is involved in the etiology of, and the best use of SSRIs for potentially treating, affective disorders in the pregnant and postpartum populations.

Does education attenuate the genetic risk of obesity? Evidence from U.K. Twins

More education is associated with a lower body mass index (BMI) and likelihood of being obese. Obesity and BMI also have a strong genetic basis. Given these observations, we investigate whether more education can reduce obesity by attenuating the underlying genetic risk of being obese, through gene-environment (GxE) interactions. We estimate associations between (i) education, (ii) a genetic risk score (GRS) and (iii) GxE interactions between education and the GRS through Ordinary least Squares (OLS) and twins fixed-effect regressions using data on female twins from the TwinsUK database. OLS estimates show that there are significant associations of education and genetics. Female twins with a university education are 14.3 percentage points less likely to be obese compared to twins with less than compulsory education, and a 1 standard deviation increase in the GRS increases the likelihood of being obese by 5.2 percentage points. The GxE interactions are statistically insignificant, suggesting that the marginal association of the GRS with obesity does not differ by educational attainment. When controlling for confounding through twins fixed-effects, we find a smaller role of genetics. The association of the GRS with obesity decreases to 0.040. Associations of educational attainment are substantially reduced and insignificant. GxE interactions also remain insignificant. Overall, we find little evidence of any GxE interactions.

The role of tryptophan metabolism in postpartum depression

The Postpartum depression (PPD) is the most common postpartum psychiatric disorder, afflicting approximately 10%-20% of new mothers. Clinical symptoms of the PPD include depressive disorder, agitation, insomnia, anxiety and confusion, resulting in an increase in suicidal tendencies, thereby having significant impacts on the puerpera, newborn and their family. A growing body of data indicate a role for alterations in tryptophan metabolism in the PPD. The metabolism of tryptophan produces an array of crucial factors that can differentially regulate key physiological processes linked to the PPD. Importantly, an increase in stress hormones and immune-inflammatory activity drives tryptophan to the production of neuroregulatory kynurenine pathway products and away from the serotonin and melatonin pathways. This links the PPD to other disorders of depressed mood, which are classically associated with decreased serotonin and melatonin, coupled to increases in kynurenine pathway products. Several kynurenine pathway products, such as kynurenic acid and quinolinic acid, can have neuroregulatory effects, with consequences pathological underpinnings of the PPD. The current article reviews the role of alterations in tryptophan metabolism in the PPD.

Chronic Stress protection for postnatal dEpREssioN prEvention (SERENE): a protocol for an exploratory study

INTRODUCTION

The prevalence of postnatal depression (PND) is significant: reaching up to 20% in the general population. In mechanistic terms, the risk of PND lies in an interaction between a maternal psychophysiological vulnerability and a chronic environmental context of stress. On the one hand, repetition of stressor during pregnancy mimics a chronic stress model that is relevant to the study of the allostatic load and the adaptive mechanisms. On the other hand, vulnerability factors reflect a psychological profile mirroring mindfulness functioning (psychological quality that involves bringing one's complete and non-judgemental attention to the present experience on a moment-to-moment basis). This psychological resource is linked to protective and resilient psychic functioning. Thus, PND appears to be a relevant model for studying the mechanisms of chronic stress and vulnerability to psychopathologies.In this article, we present the protocol of an ongoing study (started in May 2017).

METHODS AND ANALYSIS

The study is being carried out in five maternities and will involve 260 women. We aim to determine the predictive psychobiological factors for PND emergence and to provide a better insight into the mechanisms involved in chronic stress during pregnancy. We use a multidisciplinary approach that encompasses psychological resources and biophysiological and genetic profiles in order to detect relevant vulnerability biomarkers for chronic stress and the development of PND. To do so, each woman will be involved in the study from her first trimester of pregnancy until 12 months postdelivery.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Ile de France III Ethics Committee, France (2016-A00887-44). We aim to disseminate the findings through international conferences and international peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03088319; Pre-results.

Sex differences in depression during pregnancy and the postpartum period

Women have a lifetime risk of major depression double that of men but only during their reproductive years. This sex difference has been attributed partially to activational effects of female sex steroids and also to the burdens of pregnancy, childbirth, and parenting. Men, in contrast, have a reproductive period difficult to delineate, and research on the mental health of men has rarely considered the effects of fatherhood. However, the couple goes through a number of potentially stressing events during the reproductive period, and both mothers and fathers are at risk of developing peripartum depression. This Review discusses the literature on maternal and paternal depression and the endocrine changes that may predispose a person to depression at this stage of life, with specific focus on the hypothalamus–pituitary axis, oxytocin, and testosterone levels in men. Important findings on sex differences in the neural correlates of maternal and paternal behavior have emerged, highlighting the relevance of the emotional brain in mothers and the sociocognitive brain in fathers and pointing toward the presence of a common parents' brain. Additionally, sex differences in neurogenesis and brain plasticity are described in relation to peripartum depression. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.

Reproductive Affective Disorders: a Review of the Genetic Evidence for Premenstrual Dysphoric Disorder and Postpartum Depression

PURPOSE OF REVIEW

The purpose of this study is to review and summarize the literature exploring the genetic basis for premenstrual dysphoric disorder (PMDD) and postpartum depression (PPD).

RECENT FINDINGS

There is more evidence for a genetic basis for PPD than for PMDD, but only when PPD is defined as beginning in the immediate postpartum time period. Familial, genome-wide linkage and association studies, and candidate gene studies, most in the past 10 years, have examined the genetic etiology of reproductive affective disorders, including PMDD and PPD. The most commonly studied genes include SERT, COMT, MAOA, BDNF, and ESR1 and 2. This qualitative review of the recent literature finds limited evidence so far for the genetic basis for PMDD, with both familial and candidate gene studies having negative or conflicting results. Evidence is stronger for the genetic basis for PPD, with positive associations found in family studies and in several genes associated with major depression as well as genes involved in estrogen signaling but only when PPD onset is shortly after delivery. Epigenetic biomarkers on genes responsive to estrogen have also been found to predict PPD. Our findings underscore the need for additional studies with larger samples, as well as the crucial importance of timing in the definition of PPD for genetic studies.

Father Loss and Child Telomere Length

BACKGROUND AND OBJECTIVES

Father loss during childhood has negative health and behavioral consequences, but the biological consequences are unknown. Our goal was to examine how father loss (because of separation and/or divorce, death, or incarceration) is associated with cellular function as estimated by telomere length.

METHODS

Data come from the 9-year follow-up of the Fragile Families and Child Wellbeing Study, a birth cohort study of children in 20 large American cities (N = 2420). Principal measures are as follows: salivary telomere length (sTL), mother reports of father loss, and polymorphisms in genes related to serotonergic and dopaminergic signaling.

RESULTS

At 9 years of age, children with father loss have significantly shorter telomeres (14% reduction). Paternal death has the largest association (16%), followed by incarceration (10%), and separation and/or divorce (6%). Changes in income partially mediate these associations (95% mediation for separation and/or divorce, 30% for incarceration, and 25% for death). Effects are 40% greater for boys and 90% greater for children with the most reactive alleles of the serotonin transporter genes when compared with those with the least reactive alleles. No differences were found by age at father loss or a child's race/ethnicity.

CONCLUSIONS

Father loss has a significant association with children's sTL, with the death of a father showing the largest effect. Income loss explains most of the association between child sTL and separation and/or divorce but much less of the association with incarceration or death. This underscores the important role of fathers in the care and development of children and supplements evidence of the strong negative effects of parental incarceration.

Interactions between calcium intake and polymorphisms in genes essential for calcium reabsorption and risk of colorectal neoplasia in a two-phase study

The SLC8A1 (solute carrier family 8, member 1) gene, encoding Na⁺ /Ca²⁺ exchanger, is essential in regulating calcium reabsorption and homeostasis. Calcium homeostasis plays a key role in cell proliferation and apoptosis. We hypothesized that polymorphisms in five calcium-regulating genes (SLC8A1, ATP2B1, CALB1, CALB2, and CABP1) interact with calcium intake in relation to the risk of colorectal neoplasia. A two-phase (discovery and replication) study was conducted within the Tennessee Colorectal Polyp Study, including a total of 1275 cases and 2811 controls. In Phase I, we identified six out of 135 SNPs that significantly interacted with calcium intake in relation to adenoma risk. In Phase II, the calcium intake by rs4952490 (SLC8A1) interaction was replicated (P_interaction  = 0.048). We found an inverse association between calcium intake (1000-2000 mg/day) and colorectal adenomas, particularly for multiple/advanced adenomas, among the G-allele carriers but not among homozygous carriers of the common variant (A) in rs4952490. In the joint analysis of SLC8A1, KCNJ1, and SLC12A1 SNPs, carriers of variant alleles in at least two genes and with calcium intake above the DRI (1000 mg/day) were approximately 30-57% less likely to have adenomas than those whose calcium intake was below the DRI. The association was stronger for multiple/advanced adenomas. No association was found among those who did not carry any variant alleles in these genes when calcium intake was below 2500 mg/day. These findings, if confirmed, may provide a new avenue for the personalized prevention of colorectal adenoma and cancer.

Differential sensitivity to the environment: contribution of cognitive biases and genes to psychological wellbeing

Negative cognitive biases and genetic variation have been associated with risk of psychopathology in largely independent lines of research. Here, we discuss ways in which these dynamic fields of research might be fruitfully combined. We propose that gene by environment (G × E) interactions may be mediated by selective cognitive biases and that certain forms of genetic 'reactivity' or 'sensitivity' may represent heightened sensitivity to the learning environment in a 'for better and for worse' manner. To progress knowledge in this field, we recommend including assessments of cognitive processing biases; examining G × E interactions in 'both' negative and positive environments; experimentally manipulating the environment when possible; and moving beyond single-gene effects to assess polygenic sensitivity scores. We formulate a new methodological framework encapsulating cognitive and genetic factors in the development of both psychopathology and optimal wellbeing that holds long-term promise for the development of new personalized therapies.

Sensory processing sensitivity and serotonin gene variance: Insights into mechanisms shaping environmental sensitivity

Current research supports the notion that the apparently innate trait Sensory Processing Sensitivity (SPS) may act as a modulator of development as function of the environment. Interestingly, the common serotonin transporter linked polymorphic region (5-HTTLPR) does the same. While neural mechanisms underlying SPS are largely unknown, those associated with the 5-HTTLPR have been extensively investigated. We perform a comparative analysis of research findings on sensory processing facets associated with the trait and polymorphism to: 1. detect shared phenotypes and frame a hypothesis towards neural mechanisms underlying SPS; 2. increase the understanding of 5-HTTLPR-associated behavioral patterns. Trait and polymorphism are both associated with differential susceptibility to environmental stimuli; additionally, both involve 1. having stronger emotional reactions, 2. processing of sensory information more deeply, 3. being more aware of environmental subtleties, and 4. being easily overstimulated. We discuss neural mechanisms and environmental conditions that may underlie these four facets. Besides urging the actual assessment of the link between the two, the conclusions of our analyses may guide and focus future research strategies.

Opportunities and challenges of big data for the social sciences: The case of genomic data

In this paper, we draw attention to one unique and valuable source of big data, genomic data, by demonstrating the opportunities they provide to social scientists. We discuss different types of large-scale genomic data and recent advances in statistical methods and computational infrastructure used to address challenges in managing and analyzing such data. We highlight how these data and methods can be used to benefit social science research.

Depressive symptoms in adolescence: The role of perceived parental support, psychological control, and proactive control in interaction with 5-HTTLPR

BACKGROUND

Parenting dimensions are associated with depressive symptoms in adolescents. We investigated the role of perceived parenting dimensions and gene-environment interactions between these perceived parenting dimensions and five well-known variable number of tandem repeats (VNTRs): 5-HTTLPR, STin2, DAT1, DRD4, and MAO-A, in depressive symptoms.

METHODS

From a non-clinical sample of 1111 Belgian adolescents (mean age: 13.79 years, SD=.94; 51% boys), 1103 adolescents consented for genetic research. Five VNTRs were analyzed using DNA from saliva samples. Perceived parenting dimensions (i.e., support, proactive control, psychological control, punishment, and harsh punishment) were examined using self-report scales completed by adolescents and their parents. Depressive symptoms were investigated using the CES-D self-report scale. Statistical analyses were performed in R using linear regression.

RESULTS

Parental support, as perceived by the adolescent, was negatively associated with depressive symptoms (CES-D) and psychological control was positively associated with these symptoms. The only interaction effect withstanding correction for multiple testing was observed for 5-HTTLPR and the difference in proactive control as perceived by adolescents in comparison to parents. Short-allele carriers showed more depressive symptoms when there was a higher discrepancy in proactive control as perceived by adolescents versus parents.

CONCLUSIONS

Our results suggest that perceived parenting dimensions are associated with depressive symptoms, as measured by the CES-D. We only found modest evidence for 5-HTTLPR as a moderator in the association between the difference in perception of proactive control (adolescents vs. parents) and depressive symptoms.

Prepregnancy Obesity and a Biobehavioral Predictive Model for Postpartum Depression

OBJECTIVE

To test a predictive model of the associations among prepregnancy body mass index (BMI), third-trimester biological and behavioral variables, and symptoms of depression at 4 weeks postpartum.

DESIGN

Secondary data analysis from a longitudinal, biobehavioral repeated-measures study of women during the third trimester of pregnancy through 6 months postpartum.

SETTING

Communities surrounding a Midwestern and a Western U.S. city.

PARTICIPANTS

Participants were 111 women enrolled during their third trimesters of pregnancy who were studied through 4 weeks postpartum.

METHODS

Whole blood and saliva were used for biological measures, and validated questionnaires were used for behavioral measures. Principal component analysis and path analysis with principal component variables were used to iteratively test the model.

RESULTS

There were three statistically significant direct effects in the model: the path from prepregnancy BMI to inflammation, the path from prepregnancy BMI to stress, and the path from stress to symptoms of depression at 4 weeks postpartum. Indirect effects of prepregnancy BMI on postpartum depression through intervening variables were not statistically significant, nor was the model-based total effect of prepregnancy BMI on postpartum depression.

CONCLUSION

Stress was significantly linked to prepregnancy BMI and postpartum depression. This finding highlights continuing possibilities for improving outcomes for mothers, infants, and families through stress-mitigating preventive strategies.

Affective changes during the postpartum period: Influences of genetic and experiential factors

This article is part of a Special Issue "Parental Care". The postpartum period involves some truly transformational changes in females' socioemotional behaviors. For most female laboratory rodents and women, these changes include an improvement in their affective state, which has positive consequences for their ability to sensitively care for their offspring. There is heterogeneity among females in the likelihood of this positive affective change, though, and some women experience elevated anxiety or depression (or in rodents anxiety- or depression-related behaviors) after giving birth. We aim to contribute to the understanding of this heterogeneity in maternal affectivity by reviewing selected components of the scientific literatures on laboratory rodents and humans examining how mothers' physical contact with her infants, genetics, history of anxiety and depression and early-life and recent-life experiences contribute to individual differences in postpartum affective states. These studies together indicate that multiple biological and environmental factors beyond female maternal state shape affective responses during the postpartum period, and probably do so in an interactive manner. Furthermore, the similar capacity of some of these factors to modulate anxiety and depression in human and rodent mothers suggests cross-species conservation of mechanisms regulating postpartum affectivity.

Peer Influence, Genetic Propensity, and Binge Drinking: A Natural Experiment and a Replication

The authors draw data from the College Roommate Study (ROOM) and the National Longitudinal Study of Adolescent Health to investigate gene-environment interaction effects on youth binge drinking. In ROOM, the environmental influence was measured by the precollege drinking behavior of randomly assigned roommates. Random assignment safeguards against friend selection and removes the threat of gene-environment correlation that makes gene-environment interaction effects difficult to interpret. On average, being randomly assigned a drinking peer as opposed to a nondrinking peer increased college binge drinking by 0.5-1.0 episodes per month, or 20%-40% the average amount of binge drinking. However, this peer influence was found only among youths with a medium level of genetic propensity for alcohol use; those with either a low or high genetic propensity were not influenced by peer drinking. A replication of the findings is provided in data drawn from Add Health. The study shows that gene-environment interaction analysis can uncover social-contextual effects likely to be missed by traditional sociological approaches.

Social support, stress, and maternal postpartum depression: A comparison of supportive relationships

A large body of literature documents the link between social support, stress, and women's mental health during pregnancy and the postpartum period; however, uncertainty remains as to whether a direct effect or stress mediating pathway best describes the relationship between these factors. Moreover, specific dimensions of social support that may be influential (family type, sources of support) have largely been neglected. Using data from the Fragile Families and Child Well-being Study (N=4150), we examine the pathway between social support, stress exposure, and postpartum depression in greater detail. Findings reveal that social support is a significant, protective factor for postpartum depression, and the variety of support providers in a woman's social network is important, especially in the context of family type. Findings also reveal the importance of considering social support and stress exposure as part of a larger causal pathway to postpartum mental health.

Epigenetics and Understanding the Impact of Social Determinants of Health

Recently, a new research agenda emphasizing interactions between social factors and health has emerged. The term social determinant of health often refers to any nonmedical factor directly influencing health. Health across the life span is strongly and adversely affected by social disadvantage. Research in epigenetics indicates that alterations in DNA methylation may provide a causal link between social adversity and health disparity. Likewise, accelerated loss of telomeres is correlated with chronic stress. Research is still required to develop an understanding of the role of epigenetics and perturbed telomere function in linking social adversity with health outcome.

Lifetime Socioeconomic Status, Historical Context, and Genetic Inheritance in Shaping Body Mass in Middle and Late Adulthood

This study demonstrates body mass in middle and late adulthood as a consequence of the complex interplay among individuals' genes, lifetime socioeconomic experiences, and the historical context in which they live. Drawing on approximately 9,000 genetic samples from the Health and Retirement Study, we first investigate how socioeconomic status (SES) over the life course moderates the impact of 32 established obesity-related genetic variants on body mass index (BMI) in middle and late adulthood. Further, we consider differences across birth cohorts in the genetic influence on BMI and cohort variations in the moderating effects of life-course SES on the genetic influence. Our analyses suggest that persistently low SES over the life course or downward mobility (e.g., high SES in childhood but low SES in adulthood) amplified the genetic influence on BMI, while persistently high SES or upward mobility (e.g., low SES in childhood but high SES in adulthood) compensated for such influence. For more recent birth cohorts, while the genetic influence on BMI became stronger, the moderating effects of lifetime SES on the genetic influence were weaker compared to earlier cohorts. We discuss these findings in light of social changes during the obesity epidemic in the United States.

Perinatal vs genetic programming of serotonin states associated with anxiety

Large numbers of women undergo antidepressant treatment during pregnancy; however, long-term consequences for their offspring remain largely unknown. Rodents exposed to serotonin transporter (SERT)-inhibiting antidepressants during development show changes in adult emotion-like behavior. These changes have been equated with behavioral alterations arising from genetic reductions in SERT. Both models are highly relevant to humans yet they vary in their time frames of SERT disruption. We find that anxiety-related behavior and, importantly, underlying serotonin neurotransmission diverge between the two models. In mice, constitutive loss of SERT causes life-long increases in anxiety-related behavior and hyperserotonemia. Conversely, early exposure to the antidepressant escitalopram (ESC; Lexapro) results in decreased anxiety-related behavior beginning in adolescence, which is associated with adult serotonin system hypofunction in the ventral hippocampus. Adult behavioral changes resulting from early fluoxetine (Prozac) exposure were different from those of ESC and, although somewhat similar to SERT deficiency, were not associated with changes in hippocampal serotonin transmission in late adulthood. These findings reveal dissimilarities in adult behavior and neurotransmission arising from developmental exposure to different widely prescribed antidepressants that are not recapitulated by genetic SERT insufficiency. Moreover, they support a pivotal role for serotonergic modulation of anxiety-related behavior.

Gender-linked stem cell alterations in stroke and postpartum depression

Stroke is a significant unmet clinical need. The current stroke treatment of tissue plasminogen activator is limited to the very acute 4.5 h after disease onset which benefits only less than 3% of ischemic stroke patients. Our overarching hypothesis advances the notion that gender, which has been established as a comorbidity factor of stroke, plays a key role in regenerative medicine, in particular stem cell therapy. We hypothesize that gender is a key factor in culture-induced stemness of adult stem cells. Our goal is to provide new evidence supporting gender effects on stroke and stem cells for the purpose of enhancing our understanding of the pathophysiology of the disease and developing novel stem cell-based therapeutics targeting gender-relevant stress hormones as manifested in a stroke-postpartum depression paradigm.

Postpartum depression: A systematic review of the genetics involved

Postpartum depression is one of the most prevalent psychopathologies. Its prevalence is estimated to be between 10% and 15%. Despite its multifactorial etiology, it is known that genetics play an important role in the genesis of this disorder. This paper reviews epidemiological evidence supporting the role of genetics in postpartum depression (PPD). The main objectives of this review are to determine which genes and polymorphisms are associated with PPD and discuss how this association may occur. In addition, this paper explores whether these genes are somehow related to or even the same as those linked to Major Depression (MD). To identify gaps in the current knowledge that require investigation, a systematic review was conducted in the electronic databases PubMed, LILACS and SciELO using the index terms “postpartum depression” and “genetics”. Literature searches for articles in peer-reviewed journals were made until April 2014. PPD was indexed 56 times with genetics. The inclusion criteria were articles in Portuguese, Spanish or English that were available by institutional means or sent by authors upon request; this search resulted in 20 papers. Genes and polymorphisms traditionally related to MD, which are those involved in the serotonin, catecholamine, brain-derived neurotrophic factor and tryptophan metabolism, have been the most studied, and some have been related to PPD. The results are conflicting and some depend on epigenetics, which makes the data incipient. Further studies are required to determine the genes that are involved in PPD and establish the nature of the relationship between these genes and PPD.

The Influence of genetic factors on peripartum depression: A systematic review

BACKGROUND

This systematic review aimed to explore the potential influence of genetic factors on the symptoms of peripartum depression and to critically analyze the methodologies employed by the examined studies.

METHODS

A systematic review of the literature indexed prior to July 2014 identified 200 articles. After applying the inclusion and exclusion criteria, 39 papers were included.

RESULTS

The papers predominantly featured a molecular genetic approach (n=35), and the majority examined polymorphisms (n=27). Most studies used samples of Caucasians living in high income countries. The results suggest that the influence of genetic factors become more consistent when methodological variations among the studies are considered. Environmental stressors are also important variables that influence the relationship between genetic factors and peripartum depressive states. In addition, differences in the influence of genetic factors were observed depending upon the precise time point during pregnancy or the postpartum period that was examined in the studies. The late stages of pregnancy and the early postpartum period were times of greater genetic vulnerability.

LIMITATIONS

This study was limited by the small number of papers reviewed and by the lack of information regarding whether the effects of genetics on peripartum depression are specific to certain ethnicities and/or stressors.

CONCLUSIONS

Genetic studies of perinatal depression reinforce a pathophysiological role of the hormonal changes inherent in the childbirth period. However, the distinction between depressive episodes that begin during pregnancy from those that begin during the postpartum period can still be useful to improve our understanding of the physiopathology of depressive disorders.

The role of reproductive hormones in postpartum depression

Despite decades of research aimed at identifying the causes of postpartum depression (PPD), PPD remains common, and the causes are poorly understood. Many have attributed the onset of PPD to the rapid perinatal change in reproductive hormones. Although a number of human and nonhuman animal studies support the role of reproductive hormones in PPD, several studies have failed to detect an association between hormone concentrations and PPD. The purpose of this review is to examine the hypothesis that fluctuations in reproductive hormone levels during pregnancy and the postpartum period trigger PPD in susceptible women. We discuss and integrate the literature on animal models of PPD and human studies of reproductive hormones and PPD. We also discuss alternative biological models of PPD to demonstrate the potential for multiple PPD phenotypes and to describe the complex interplay of changing reproductive hormones and alterations in thyroid function, immune function, hypothalamic-pituitary-adrenal (HPA) axis function, lactogenic hormones, and genetic expression that may contribute to affective dysfunction. There are 3 primary lines of inquiry that have addressed the role of reproductive hormones in PPD: nonhuman animal studies, correlational studies of postpartum hormone levels and mood symptoms, and hormone manipulation studies. Reproductive hormones influence virtually every biological system implicated in PPD, and a subgroup of women seem to be particularly sensitive to the effects of perinatal changes in hormone levels. We propose that these women constitute a "hormone-sensitive" PPD phenotype, which should be studied independent of other PPD phenotypes to identify underlying pathophysiology and develop novel treatment targets.

Developmental mediation of genetic variation in response to the Fast Track prevention program

We conducted a developmental analysis of genetic moderation of the effect of the Fast Track intervention on adult externalizing psychopathology. The Fast Track intervention enrolled 891 children at high risk to develop externalizing behavior problems when they were in kindergarten. Half of the enrolled children were randomly assigned to receive 10 years of treatment, with a range of services and resources provided to the children and their families, and the other half to usual care (controls). We previously showed that the effect of the Fast Track intervention on participants' risk of externalizing psychopathology at age 25 years was moderated by a variant in the glucocorticoid receptor gene. Children who carried copies of the A allele of the single nucleotide polymorphism rs10482672 had the highest risk of externalizing psychopathology if they were in the control arm of the trial and the lowest risk of externalizing psychopathology if they were in the treatment arm. In this study, we test a developmental hypothesis about the origins of this for better and for worse Gene × Intervention interaction (G × I): that the observed G × I effect on adult psychopathology is mediated by the proximal impact of intervention on childhood externalizing problems and adolescent substance use and delinquency. We analyzed longitudinal data tracking the 270 European American children in the Fast Track randomized control trial with available genetic information (129 intervention children, 141 control group peers, 69% male) from kindergarten through age 25 years. Results show that the same pattern of for better and for worse susceptibility to intervention observed at the age 25 follow-up was evident already during childhood. At the elementary school follow-ups and at the middle/high school follow-ups, rs10482672 predicted better adjustment among children receiving the Fast Track intervention and worse adjustment among children in the control condition. In turn, these proximal G × I effects early in development mediated the ultimate G × I effect on externalizing psychopathology at age 25 years. We discuss the contribution of these findings to the growing literature on genetic susceptibility to environmental intervention.

Steroid hormones in the development of postpartum depression

Postpartum depression affects 10-15 % women after childbirth. There is no currently generally accepted theory about the causes and mechanisms of postpartum mental disorders. The principal hypothesis concerns the association with sudden changes in the production of hormones affecting the nervous system of the mother and, on the other hand, with the ability of receptor systems to adapt to these changes. We observed changes in steroidogenesis in the period around spontaneous delivery. We collected three samples of maternal blood. The first sampling was 4 weeks prior to term; the second sampling was after the onset of uterine contractions (the beginning of spontaneous labour); the third sampling was during the third stage of labour (immediately after childbirth). Additionally, we collected mixed umbilical cord blood. The almost complete steroid metabolome was analyzed by gas chromatography-mass spectrometry followed by RIA for some steroids. Mental changes in women in the peripartum period were observed using the Hamilton Depression Rating Scale. The local Ethics Committee approved the study. We found already the changes in androgens levels correlating with postpartum mood disorders four weeks prior to childbirth. The strongest correlations between steroid and postpartum mood change were found in venous blood samples collected from mothers after childbirth and from umbilical cord blood. The main role played testosterone, possibly of maternal origin, and estrogens originating from the fetal compartment. These results suggest that changes in both maternal and fetal steroidogenesis are involved in the development of mental changes in the postpartum period. Descriptions of changes in steroidogenesis in relation to postpartum depression could help clarify the causes of this disease, and changes in some steroid hormones are a promising marker of mental changes in the postpartum period.

Biological and psychosocial predictors of postpartum depression: systematic review and call for integration

Postpartum depression (PPD) adversely affects the health and well being of many new mothers, their infants, and their families. A comprehensive understanding of biopsychosocial precursors to PPD is needed to solidify the current evidence base for best practices in translation. We conducted a systematic review of research published from 2000 through 2013 on biological and psychosocial factors associated with PPD and postpartum depressive symptoms. Two hundred fourteen publications based on 199 investigations of 151,651 women in the first postpartum year met inclusion criteria. The biological and psychosocial literatures are largely distinct, and few studies provide integrative analyses. The strongest PPD risk predictors among biological processes are hypothalamic-pituitary-adrenal dysregulation, inflammatory processes, and genetic vulnerabilities. Among psychosocial factors, the strongest predictors are severe life events, some forms of chronic strain, relationship quality, and support from partner and mother. Fully integrated biopsychosocial investigations with large samples are needed to advance our knowledge of PPD etiology.