Effects of ovarian steroids and raloxifene on proteins that synthesize, transport, and degrade serotonin in the raphe region of macaques

Relationship of monoamine oxidase-A distribution volume to postpartum depression and postpartum crying

Postpartum depression (PPD) has a prevalence rate of 13% and a similarly high proportion of women report a subclinical state of one or more major depressive episode symptoms. The aim was to investigate whether monoamine oxidase-A (MAO-A) VT, an index of MAO-A density, is increased in the prefrontal and anterior cingulate cortex (PFC and ACC), during PPD or when a PPD spectrum symptom, greater predisposition to crying, is present. MAO-A is an enzyme that increases in density after estrogen decline, and has several functions including creating oxidative stress, influencing apoptosis and monoamine metabolism. Fifty-seven women were recruited including 15 first-onset, antidepressant naive, PPD subjects, 12 postpartum healthy who cry due to sad mood, 15 asymptomatic postpartum healthy women, and 15 healthy women not recently pregnant. Each underwent [(11)C]-harmine positron emission tomography scanning to measure MAO-A VT. Both PPD and greater predisposition to crying were associated with greater MAO-A VT in the PFC and ACC (multivariate analysis of variance (MANOVA), group effect, F21,135=1.856; p=0.019; mean combined region elevation 21% and 14% in PPD and crying groups, respectively, relative to postpartum asymptomatic). Greater MAO-A VT in the PFC and ACC represents a new biomarker in PPD, and the PPD symptom of predisposition to crying. Novel strategies for preventing PPD (and some PPD symptoms) may be possible by avoiding environmental conditions that elevate MAO-A level and enhancing conditions that normalize MAO-A level. These findings also argue for clinical trials in PPD with the newer, well-tolerated MAO-A inhibitor antidepressants.

The Antidepressant-like Effects of Estrogen-mediated Ghrelin

Ghrelin, one of the brain-gut peptides, stimulates food-intake. Recently, ghrelin has also shown to play an important role in depression treatment. However, the mechanism of ghrelin's antidepressant-like actions is unknown. On the other hand, sex differences in depression, and the fluctuation of estrogens secretion have been proved to play a key role in depression. It has been reported that women have higher level of ghrelin expression, and ghrelin can stimulate estrogen secretion while estrogen acts as a positive feedback mechanism to up-regulate ghrelin level. Ghrelin may be a potential regulator of reproductive function, and estrogen may have additional effect in ghrelin's antidepressantlike actions. In this review, we summarize antidepressant-like effects of ghrelin and estrogen in basic and clinical studies, and provide new insight on ghrelin's effect in depression.

Effects of estrogen on the serotonergic system and calcitonin gene-related peptide in trigeminal ganglia of rats

BACKGROUND

The prevalence of migraine is 3-folds higher in females than in males, and it is intricately related to the levels of estrogen. Estrogen may regulate the expression of metabolic enzymes and receptors of serotonin and also calcitonin gene-related peptide (CGRP), which are implicated in migraine pathogenesis.

PURPOSE

To study the effects of estrogen on the components of serotonin system and CGRP in trigeminal ganglia of ovariectomized (OVX) rats.

METHODS

OVX rats were administered estrogen in silastic tubes and after 48 h, serum estrogen levels were determined. Trigeminal ganglia tissues were used for RT-PCRs of tryptophan hydroxylase (TPH), monoamine oxidase (MAO), serotonin receptors (5-HT1A, 5-HT1B, 5-HT2A), estrogen receptor (ER) and CGRP. Western blots of TPH and MAO were performed.

RESULTS

Estradiol administration to OVX rats increased TPH mRNA levels, while decreased MAO mRNA levels in trigeminal ganglia tissue. Western blot data correlate with the gene expression results. The decreased mRNA levels of serotonin receptors following ovariectomy were restored in estrogen-replenished rats. The induced gene expression of ER in OVX rats was restored following estrogen replenishment.

CONCLUSION

Estrogen levels affect the levels of serotonin metabolizing enzymes and its receptors besides CGRP levels. Since TPH and MAO levels regulate circulating and physiologically available serotonin content, the regulation of serotonin metabolizing enzymes suggest a plausible mechanism by which estrogen alleviates migraine in women.

Gender difference in interactions between MAOA promoter uVNTR polymorphism and negative familial stressors on body mass index among Chinese adolescents

OBJECTIVES

Monoamine oxidase A (MAOA) modulates metabolism of serotonin and dopamine metabolism, neurotransmitters involved in regulation of appetite and food intake. The gene coding for MAOA contains a 30-bp tandem repeat (uVNTR) polymorphism in its promoter region that has been previously identified to be associated with obesity with mixed findings in the literature. Our goals were to replicate the population effects of this functional polymorphism on obesity risk, and to further explore gender differences and interaction effects with negative stressors.

METHODS

Analyses were conducted with data on genotypes, measured weight and height, and self-reported behavioural characteristics among 1101 Chinese adolescents 11-15 years old living in Wuhan, China.

RESULTS

Girls with the high-activity allele had significantly lower body mass index (BMI; β = -0.25 ± 0.98, P = 0.011) compared to those with the low activity allele. Experience of negative familial stressors (e.g., death or illness of family members, hit or scolded by parents and increased quarrelling with parents, parents argued frequently) significantly weakened this protective genetic effect on BMI (P for interaction = 0.043). Stratified analyses showed a significant protective genetic effect on BMI only within the stratum of low stress level (β = -0.44 ± 0.14, P = 0.002). No similar effect was observed among boys.

CONCLUSIONS

Our findings confirm the genetic effects of MAOA uVNTR polymorphism on BMI in a Chinese adolescent population and suggest potential genetic interactions with negative familial stressors.

Greater monoamine oxidase a binding in perimenopausal age as measured with carbon 11-labeled harmine positron emission tomography

IMPORTANCE

Perimenopause is a period of high risk for mood disorders, and it has been proposed that perimenopause is also a window of risk for processes linked to later dementia. However, in human perimenopause, the neurobiological changes implicated in the genesis of mood disorders or dementia have not been identified. Monoamine oxidase A (MAO-A) is an important brain enzyme that creates oxidative stress, influences apoptosis, and metabolizes monoamines. After declines in estrogen level, MAO-A density may be elevated for a month or longer, and repeated declines in estrogen level occur with greater magnitude during perimenopause.

OBJECTIVE

To investigate whether MAO-A total distribution volume (VT), an index of MAO-A density, is elevated in women of perimenopausal age (41-51 years).

DESIGN, SETTING, AND PARTICIPANTS

In a cross-sectional study at a tertiary care psychiatric hospital, 58 women underwent carbon 11-labeled harmine positron emission tomography. These included 19 young women of reproductive age (mean [SD], 28.26 [5.05] years), 27 women of perimenopausal age (mean [SD] age, 45.21 [3.41] years; including 14 women with change in menstrual cycle length with a mean [SD] age of 45.50 [4.00] years and 13 women with no change in menstrual cycle length with a mean [SD] age of 44.92 [2.81] years), and 12 women in menopause (mean [SD] age, 56.25 [3.19] years).

MAIN OUTCOMES AND MEASURES

Values of MAO-A VT in the prefrontal cortex, anterior cingulate cortex, dorsal striatum, ventral striatum, thalamus, hippocampus, and midbrain.

RESULTS

On average, MAO-A VT in perimenopausal age was elevated by 34% compared with reproductive age and by 16% compared with menopause (multivariate analysis of variance, group effect, F16,94 = 3.03; P < .001). Within the perimenopausal age group, meeting Stages of Reproductive Aging Workshop criteria for perimenopause, which is mainly based on menstrual cycle length, was not associated with MAO-A VT (F8,18 = 0.548; P = .81) but tendency to cry was positively correlated with MAO-A VT in the prefrontal cortex (r = 0.54; P = .008).

CONCLUSIONS AND RELEVANCE

To our knowledge, this is the first report of a change in a central biomarker during perimenopausal age that is also present during major depressive episodes and high-risk states for major depressive episodes. The functions of MAO-A influence oxidative stress and apoptosis, 2 processes implicated as excessive in both mood disorders and dementia. Hence, greater MAO-A VT during perimenopause may represent a new target for assessing novel interventions to prevent mood disorders and reduce longer-term risk of neurodegenerative disease.

Gender-related differences in irritable bowel syndrome: Potential mechanisms of sex hormones

According to epidemiological studies, twice as many women as men are affected by irritable bowel syndrome (IBS) in western countries, suggesting a role for sex hormones in IBS pathophysiology. Despite growing evidence about the implications of sex hormones in IBS symptom modulation, data on mechanisms by which they influence disease development are sparse. This review aims to determine the state of knowledge about the role of sex hormones in sensorimotor dysfunctions and to address the possible interplay of sex hormones with common risk factors associated with IBS. The scientific bibliography was searched using the following keywords: irritable bowel syndrome, sex, gender, ovarian hormone, estradiol, progesterone, testosterone, symptoms, pain, sensitivity, motility, permeability, stress, immune system, brain activity, spinal, supraspinal, imaging. Ovarian hormones variations along the menstrual cycle affect sensorimotor gastrointestinal function in both healthy and IBS populations. They can modulate pain processing by interacting with neuromodulator systems and the emotional system responsible for visceral pain perception. These hormones can also modulate the susceptibility to stress, which is a pivotal factor in IBS occurrence and symptom severity. For instance, estrogen-dependent hyper-responsiveness to stress can promote immune activation or impairments of gut barrier function. In conclusion, whereas it is important to keep in mind that ovarian hormones cannot be considered as a causal factor of IBS, they arguably modulate IBS onset and symptomatology. However, our understanding of the underlying mechanisms remains limited and studies assessing the link between IBS symptoms and ovarian hormone levels are needed to improve our knowledge of the disease evolution with regard to gender. Further studies assessing the role of male hormones are also needed to understand fully the role of sex hormones in IBS. Finally, investigation of brain-gut interactions is critical to decipher how stress, ovarian hormones, and female brain processing of pain can translate into gut dysfunctions.

Pharmacology of serotonin and female sexual behavior

In this review, first a historical perspective of serotonin's (5-HT) involvement in female sexual behavior is presented. Then an overview of studies implicating 5-HT is presented. The effect of drugs that increase or decrease CNS levels of 5-HT is reviewed. Evidence is presented that drugs which increase 5-HT have negative effects on female sexual behavior while a decrease in 5-HT is associated with facilitation of sexual behavior. Studies with compounds that act on 5-HT₁, 5-HT₂ or 5-HT₃ receptors are discussed. Most evidence indicates that 5-HT₁A receptor agonists inhibit sexual behavior while 5-HT₂ or 5-HT₃ receptors may exert a positive influence. There is substantial evidence to support a role for 5-HT in the modulation of female consummatory sexual behavior, but studies on the role of 5-HT in other elements of female sexual behavior (e.g. desire, motivation, sexual appetite) are few. Future studies should be directed at determining if these additional components of female sexual behavior are also modulated by 5-HT.

Increased blood serotonin concentrations are correlated with reduced tension/anxiety in healthy postpartum lactating women

The serotonin (5-HT) system in the brain plays an important role in mood regulation. The postpartum period is considered a high-risk time for mood and anxiety disorders. We assessed changes in 5-HT levels in whole blood (as an indicator of brain 5-HT concentrations) and mood states before and after delivery in 28 healthy, lactating postpartum women. Mood states were evaluated using Profile of Mood States questionnaires (POMS). Measurements were done on the same day in early (first week) and late (third-fourth and sixth-seventh weeks) postpartum, and compared with those in the third trimester and in age-matched, healthy, non-pregnant women. Mean 5-HT concentrations were significantly higher and mean tension/anxiety scores of POMS were significantly lower in late (but not early) postpartum than in the third trimester or non-pregnant controls. 5-HT concentrations correlated with tension/anxiety in the third trimester and late postpartum, indicating an important role for the 5-HT system in the regulation of tension/anxiety in healthy postpartum women. The mechanism underlying the changes in the 5-HT system may be rapid inhibition induced by the marked decrease in estradiol after delivery and gradual excitation caused by lactation-induced brain oxytocin release during the postpartum period.

Genetic and epigenetic associations of MAOA and NR3C1 with depression and childhood adversities

Monoamine oxidase A (MAOA) harbours a polymorphic upstream variable-number tandem repeat (u-VNTR). The MAOA-L allele of the u-VNTR leads to decreased gene expression levels in vitro and has been found to increase the risk of conduct disorder in males with childhood adversities. Early-life adversities have been associated with hypermethylation of the glucocorticoid receptor (NR3C1). In this study, we first performed a genetic association analysis of the MAOA u-VNTR using individuals with depression (n = 392) and controls (n = 1276). Next, DNA methylation analyses of MAOA and NR3C1 were performed using saliva samples of depressed and control subgroups. Adult MAOA-L females with childhood adversities were found to have a higher risk of developing depression (p = 0.006) and overall MAOA methylation levels were decreased in depressed females compared to controls (mean depressed, 42% vs. mean controls, 44%; p = 0.04). One specific childhood adversity [early parental death (EPD)] was associated with hypermethylation of NR3C1 close to an NGFI-A binding site (mean EPD, 19% vs. mean non-EPD, 14%; p = 0.005). Regression analysis indicated that this association may be mediated by the MAOA-L allele (adjusted R² = 0.24, ANOVA: F = 23.48, p < 0.001). Conclusively: (1) depression in females may result from a gene × childhood-adversity interaction and/or a dysregulated epigenetic programming of MAOA; (2) childhood-adversity subtypes may differentially impact DNA methylation at NR3C1; (3) baseline MAOA-genotypic variations may affect the extent of NR3C1 methylation.

Estrogen signaling and the aging brain: context-dependent considerations for postmenopausal hormone therapy

Recent clinical studies have spurred rigorous debate about the benefits of hormone therapy (HT) for postmenopausal women. Controversy first emerged based on a sharp increase in the risk of cardiovascular disease in participants of the Women's Health Initiative (WHI) studies, suggesting that decades of empirical research in animal models was not necessarily applicable to humans. However, a reexamination of the data from the WHI studies suggests that the timing of HT might be a critical factor and that advanced age and/or length of estrogen deprivation might alter the body's ability to respond to estrogens. Dichotomous estrogenic effects are mediated primarily by the actions of two high-affinity estrogen receptors alpha and beta (ER α & ER β ). The expression of the ERs can be overlapping or distinct, dependent upon brain region, sex, age, and exposure to hormone, and, during the time of menopause, there may be changes in receptor expression profiles, post-translational modifications, and protein:protein interactions that could lead to a completely different environment for E2 to exert its effects. In this review, factors affecting estrogen-signaling processes will be discussed with particular attention paid to the expression and transcriptional actions of ER β in brain regions that regulate cognition and affect.

Estrogen, cognitive functions and emotion: an overview on humans, non-human primates and rodents in reproductive years

Accumulating evidence has highlighted a number of important, global issues regarding the influence of estrogen on emotion and cognitive functions,including learning and memory processes, both in animal models and humans. The influence of estrogen on cognition and emotion can be explained by taking into account its modulator role on several neurotransmitter systems, acetylcholine in particular, but also catecholamines,serotonin and GABA in rodents, primates and humans. Another reason may lie in the wide spread presence of the two classes (a and~) of estrogen receptors in many brain regions involved in emotion and cognition, including the hippocampal formation, amygdala and cerebral cortex. The present review reports on research conducted in our laboratory and others with the objective of identifying the action of estrogens on cognition and emotion in rodents, monkeys and humans in youth. In particular, the first section,focused on the mechanisms of estrogens action in the brain, illustrates the involvement of estrogen receptors and neurotransmitters in the cognitive and emotional processes; the second section deals with the estrogen effects on cognitive and emotional mechanisms, with particular emphasis on memory and the involvement of estrogen in emotion and cognition across the estrous/menstrual cycle.

Effects of aromatase inhibition and androgen activity on serotonin and behavior in male macaques

Aggression in humans and animals has been linked to androgens and serotonin function. To further our understanding of the effect of androgens on serotonin and aggression in male macaques, we sought to manipulate circulating androgens and the activity of aromatase; and to then determine behavior and the endogenous availability of serotonin. Male Japanese macaques (Macaca fuscata) were castrated for 5-7 months and then treated for 3 months with (a) placebo; (b) testosterone (T); (c) T + Dutasteride (5a reductase inhibitor; AvodartTM); (d) T + Letrozole (nonsteroidal aromatase inhibitor; FemeraTM); (e) Flutamide + ATD (androgen antagonist plus steroidal aromatase inhibitor); or (f) dihydrotestosterone (DHT) + ATD (n = 5/group). Behavioral observations were made during treatments. At the end of the treatment period, each animal was sedated with propofol and administered a bolus of fenfluramine (5 mg/kg). Fenfluramine causes the release of serotonin proportional to endogenous availability and in turn, serotonin stimulates the secretion of prolactin. Therefore, serum prolactin concentrations reflect endogenous serotonin. Fenfluramine significantly increased serotonin/prolactin in all groups (p < .0001). Fenfluramine-induced serotonin/prolactin in the T-treated group was significantly higher than the other groups (p < .0001). Castration partially reduced the serotonin/prolactin response and Letrozole partially blocked the effect of T. Complete inhibition of aromatase with ATD, a noncompetitive inhibitor, significantly and similarly reduced the fenfluramine-induced serotonin/prolactin response in the presence or absence of DHT. Neither aggressive behavior nor yawning (indicators of androgen activity) correlated with serotonin/prolactin, but posited aromatase activity correlated significantly with prolactin (p < .0008; r² = 0.95). In summary, androgens induced aggressive behavior but they did not regulate serotonin. Altogether, the data suggest that aromatase activity supports serotonin production and that androgens increase aggression by another mechanism.

Serotonin and Female Psychopathology

There are sex differences in the prevalence and presentation of many psychiatric disorders. Various trends in symptomatology have emerged that are thought to be linked to periods of hormonal fluctuations such as with menses, pregnancy or menopause. With data from animal and human studies, it has become clear that there is an important interplay between the serotonergic system and gonadal hormones. The majority of the research to date has focused on the influence that estrogen has within the CNS and, in particular, how it leads to an overall increase in serotonin synthesis and availability. In reviewing this female-specific topic we hope to raise awareness to sex/gender differences in psychopathology, help identify at-risk populations and consider development of new treatment options. Future research will also need to consider the influence that progesterone and oxytocin may have on sex-specific psychopathology as well as incorporate neuroimaging and consider the influence of hormones on the serotonergic system at a genetic level.

Special biological issues in the management of women with schizophrenia

Schizophrenia is a debilitating and pervasive mental illness with devastating effects on psychological, cognitive and social wellbeing, and for which current treatment options are far from ideal. Gender differences and the influence of the female reproductive life cycle on the onset, course and symptoms of schizophrenia and the discovery of estrogen's remarkable psychoprotective properties in animal models led to the proposal of the 'estrogen protection hypothesis' of schizophrenia. This has fueled the recent successful investigation of estradiol as a potential adjuvant therapeutic agent in the management of schizophrenia in women. This review explains the scientific rationale behind the estrogen hypothesis and how it can be clinically utilized to address concerns unique to the care of women with schizophrenia.

Comparison of the effects of estradiol and progesterone on serotonergic function

BACKGROUND

Ovarian hormones may contribute to the vulnerability to depression, as well as to the response to antidepressants (ADs). Previously, we reported that acute systemic treatment with estradiol or progesterone blocked the ability of the selective serotonin reuptake inhibitor, fluvoxamine, to inhibit serotonin transporter function in ovariectomized rats. In this study, behavioral consequences, as well as receptor mechanisms underlying these hormonal effects, were investigated.

METHODS

Using the forced swimming test, the acute effect of estradiol and/or progesterone on fluvoxamine's AD-like effects was investigated. Using in vivo chronoamperometry, the effect of local application of estradiol or progesterone into the hippocampus of ovariectomized rats on serotonin (5-HT) clearance, as well as on the ability of fluvoxamine to slow 5-HT clearance, were investigated.

RESULTS

The decreased immobility and increased swimming caused by fluvoxamine in the forced swimming test was blocked in rats treated with estradiol and/or progesterone. Local application of estradiol, but not progesterone, slowed 5-HT clearance and both hormones blocked the ability of fluvoxamine to slow 5-HT clearance. Use of hormone receptor agonists and antagonists, revealed that the effects of estradiol are mediated by activation of membrane, as well as nuclear estrogen receptors (ER). The AD-like effect of estradiol involved ER beta and G-protein coupled receptor 30, whereas its blockade of fluvoxamine's effects was ER alpha-mediated. The effects of progesterone occurred solely by activation of intracellular progesterone receptors.

CONCLUSIONS

Targeting of ER beta or G-protein coupled receptor 30 might reveal a strategy to permit beneficial effects of estrogen without its deleterious effect on selective serotonin reuptake inhibitor efficacy.

Reproductive depression

Reproductive depression is the depression in women that is related to the hormonal changes of the menstrual cycle, pregnancy and the menopause and is manifested clinically as premenstrual depression, postnatal depression and climacteric depression. These three components occur in the same vulnerable women in that a woman with depression in the menopausal transition will usually have a history of premenstrual syndrome (PMS; premenstrual dysphoric disorder [PMDD]), would have been in a good mood during pregnancy and then develop postnatal depression. When the periods return the depression becomes cyclical as PMS. These three conditions are effectively treated with transdermal estrogens which should be the first-choice therapy rather than antidepressants. Estrogens can be used together with antidepressants. The critical time to prevent long-term mood problems is the correct treatment of postnatal depression. In women with low energy and libido, often a side effect of antidepressants, the addition of transdermal testosterone is useful. These women with reproductive depression are often progesterone/progestogen intolerant and a smaller dose or duration of progestogen is a necessary compromise. Alternatively a Mirena IUS or rarely a hysterectomy is required.

Interactive effects of estrogen and serotonin on brain activation during working memory and affective processing in menopausal women

While cognitive changes and mood instability are frequent symptoms reported by menopausal women, the degree to which the decline in estrogen production is responsible is not yet clear. Several lines of evidence suggest that estrogen may produce its effects on cognition and mood through modulation of serotonergic function. To test this hypothesis, we used the tryptophan depletion (TD) paradigm to lower central serotonin levels and pharmacologically manipulated estrogen levels in healthy menopausal women. We examined the individual and combined effects of estradiol and serotonin on working memory, emotion processing and task-related brain activation. Eight healthy predominantly early postmenopausal women underwent TD or sham depletion followed by functional magnetic resonance imaging (fMRI) both before and after short-term transdermal estradiol 75-150 μg/d administration. There was an estradiol treatment by TD interaction for brain activation during performance on both the N-back Task (working memory) and Emotion Identification Task (affective processing). During the 2-back condition, TD attenuated activation prior to, but not after, estradiol treatment in the right and left dorsal lateral prefrontal and middle frontal/cingulate gyrus. During emotion identification, TD heightened activation in the orbital frontal cortex and bilateral amygdala, and this effect was attenuated by estradiol treatment. These results provide preliminary evidence that serotonergic effects directly mediate the impact of estrogen on brain activation during working memory and affective processing.

Selective estrogen receptor modulators regulate dendritic spine plasticity in the hippocampus of male rats

Some selective estrogen receptor modulators, such as raloxifene and tamoxifen, are neuroprotective and reduce brain inflammation in several experimental models of neurodegeneration. In addition, raloxifene and tamoxifen counteract cognitive deficits caused by gonadal hormone deprivation in male rats. In this study, we have explored whether raloxifene and tamoxifen may regulate the number and geometry of dendritic spines in CA1 pyramidal neurons of the rat hippocampus. Young adult male rats were injected with raloxifene (1 mg/kg), tamoxifen (1 mg/kg), or vehicle and killed 24 h after the injection. Animals treated with raloxifene or tamoxifen showed an increased numerical density of dendritic spines in CA1 pyramidal neurons compared to animals treated with vehicle. Raloxifene and tamoxifen had also specific effects in the morphology of spines. These findings suggest that raloxifene and tamoxifen may influence the processing of information by hippocampal pyramidal neurons by affecting the number and shape of dendritic spines.

Influence and interaction of genetic polymorphisms in catecholamine neurotransmitter systems and early life stress on antidepressant drug response

BACKGROUND

Catecholamine neurotransmission plays an important role in major depression. Variation in genes implicated in the synthesis and signal transduction of catecholamines (norepinephrine and dopamine) may interact with environmental factors to affect the outcome of antidepressant treatment. We aimed to determine how a range of polymorphisms in noradrenergic and dopaminergic genes influence this response to treatment and how they interact with childhood trauma and recent life stress in a Chinese sample.

METHODS

In a sample of 308 Chinese Han patients with major depressive disorder, 13 single nucleotide polymorphisms (SNPs) in coding regions of six genes (MAOA, SLC6A2, TH, COMT, DRD2, DRD3) with minor allele frequencies >5% were successfully genotyped from an initial series of 35 SNPs in 11 candidate genes associated with catecholamine neurotransmission. The responses to 6 weeks' treatment with antidepressant drugs was determined by changes in the 17-item Hamilton Depression Rating Scale (HAMD-17) score, and previous stressful events were evaluated by the Life Events Scale (LES) and Childhood Trauma Questionnaire-Short Form (CTQ-SF). Single SNP and haplotype associations with treatment response were analysed by UNPHASED 3.0.13, gene-gene interactions were analysed by generalized multifactor dimensionality reduction (GMDR) and gene-environment interactions by logistic regression.

RESULTS

A haplotype in MAOA (rs1137070 and rs6323) was significantly associated with antidepressant response in the total group, the nonSSRI subgroup and the female subgroup. Two haplotypes in COMT (involving rs4633, rs4818 and rs769224) were significantly associated with antidepressant response in the nonSSRI subgroup. The SLC6A2 SNPs interacted with childhood trauma to influence antidepressant response.

CONCLUSIONS

A haplotype in MAOA and two haplotypes in COMT are found to be associated with antidepressant treatment response in this sample. Stressors in early life may interact with polymorphisms in SLC6A2 to influence response to antidepressant treatment.

Genetics of menstrual migraine: the molecular evidence

Migraine is considered to be a multifactorial disorder in which genetic, environmental, and, in the case of menstrual and menstrually related migraine, hormonal events influence the phenotype. Certainly, the role of female sex hormones in migraine has been well established, yet the mechanism behind this well-known relationship remains unclear. This review focuses on the potential role of hormonally related genes in migraine, summarizes results of candidate gene studies to date, and discusses challenges and issues involved in interpreting hormone-related gene results. In light of the molecular evidence presented, we discuss future approaches for analysis with the view to elucidate the complex genetic architecture that underlies the disorder.

Long-term ovariectomy decreases serotonin neuron number and gene expression in free ranging macaques

The serotonin system responds to the ovarian steroids, estradiol (E) and progesterone (P), in women and female animal models. In macaques, ovarian steroid administration to ovariectomized (Ovx) individuals improves serotonin neural function through actions on pivotal serotonin-related genes and proteins, such as TPH2 (tryptophan hydroxylase 2), SERT (serotonin reuptake transporter), and the 5HT1A autoreceptor. In addition, ovarian steroid administration reduces gene and protein expression in the caspase-independent pathway and reduces DNA fragmentation in serotonin neurons. This study examines the hypothesis that long-term ovariectomy will lead to a loss of serotonin neurons and compromised gene expression in serotonin neurons. Female Japanese macaques were ovariectomized or tubal ligated (n=5/group) at 3 years of age and returned to their natal troop. After 3 years, the animals were collected, administered a fenfluramine challenge to determine global serotonin availability, and then euthanized. Fev, TPH2, SERT, and 5HT1A expression were examined with digoxigenin in situ hybridization (ISH) and quantitative image analysis. Cell number, positive pixel area, and average pixel density were determined. In the Ovx group, Fev, TPH2, SERT, and 5HT1A showed a significant decease in average and total cell number and positive pixel area. The reduction in Fev-positive neurons suggests that there were fewer serotonin neurons in Ovx animals compared to ovary-intact animals. The decrease in TPH2 in the Ovx animals was consistent with earlier results in 5-month Ovx animals, but it may be due to the decrease in cell number rather than a decrease in expression on an individual cell basis. The decrease in SERT and 5HT1A in long-term Ovx differed from previous studies in short-term Ovx. In summary, long-term ovarian steroid loss resulted in fewer serotonin neurons and overall lower Fev, TPH2, SERT, and 5HT1A gene expression. This may be due to serotonin cell death or to a negative impact on a long-term developmental process in young female macaques.

Overexpression or knockdown of rat tryptophan hyroxylase-2 has opposing effects on anxiety behavior in an estrogen-dependent manner

Previous studies showed that chronic estrogen treatment increases tryptophan hydroxylase-2 (TpH2) mRNA in the caudal dorsal raphe nucleus (DRN), and this increase was associated with decreased anxiety. The present study explored the interaction of estrogen and targeted, bidirectional manipulation of TpH2 expression in the caudal DRN by knockdown or viral overexpression, to decrease or increase tryptophan hydroxylase expression respectively, on anxiety behavior. Rats were ovariectomized and replaced with empty or estradiol capsules (OVX, OVX/E, respectively). Animals received microinfusions of either antisense TpH2 or control morpholino oligonucleotides into caudal DRN and were later tested in the open field test. A separate group of animals were microinfused with TpH2-GFP or GFP-only herpes simplex viral vectors into caudal DRN and tested in the open field. The bidirectional impact of manipulations on TpH2 expression was confirmed using a combination of quantitative protein and mRNA measurements; TpH2 expression changes were limited to discrete subregions of DRN that were targeted by the manipulations. Estradiol decreased anxiety in all behavioral measures. In the OVX/E group, TpH2 knockdown significantly decreased time spent in the center of the open field, but not in the OVX group, suggesting that TpH2 knockdown reduced the anxiolytic effects of estrogen. Conversely, TpH2 overexpression in the OVX group mimicked the effects of estrogen, as measured by increased time spent in the center of the open field. These results suggest that estrogen and TpH2 in the caudal DRN have a critical interaction in regulating anxiety-like behavior.

Maltreatment, MAOA, and delinquency: sex differences in gene-environment interaction in a large population-based cohort of adolescents

The present study investigated a possible interaction between a functional polymorphism in the MAOA gene promoter (MAOA-VNTR) and childhood maltreatment in the prediction of adolescent male and female delinquency. A cohort of 1,825 high school students, 17-18 years old, completed an anonymous questionnaire during class hours which included questions on childhood maltreatment, sexual abuse, and delinquency. Saliva samples were collected for DNA isolation, and analyzed for the MAOA-VNTR polymorphism. Self-reported maltreatment was a strong risk factor for adolescent delinquent behavior. The MAOA genotype also showed a significant main effect when controlled for maltreatment. Boys with a short variant and girls with one or two long variants of the polymorphism showed a higher risk for delinquency when exposed to maltreatment. Our results confirm previous findings of an interaction between the MAOA-VNTR polymorphism and self-reported maltreatment. Results for boys and girls differ according to MAOA-VNTR genotype and direction of phenotypic expression.

Conceptualizing the role of estrogens and serotonin in the development and maintenance of bulimia nervosa

Serotonergic dysregulation is thought to underlie much of the pathology in bulimia nervosa (BN). The purpose of this review is to expand the serotonergic model by incorporating specific and nonspecific contributions of estrogens to the development and maintenance of bulimic pathology in order to guide research from molecular genetics to novel therapeutics for BN. Special emphasis is given to the organizing theory of general brain arousal which allows for integration of specific and nonspecific effects of these systems on behavioral endpoints such as binge eating or purging as well as arousal states such as fear, novelty seeking, or sex. Regulation of the serotonergic system by estrogens is explored, and genetic, epigenetic, and environmental estrogen effects on bulimic pathology and risk factors are discussed. Genetic and neuroscientific research support this two-system conceptualization of BN with both contributions to the developmental and maintenance of the disorder. Implications of an estrogenic-serotonergic model of BN are discussed as well as guidelines and suggestions for future research and novel therapeutic targets.

Association of monoamine oxidase A (MAOA) polymorphisms and clinical subgroups of major depressive disorders in the Han Chinese population

It has been proposed that an MAOA abnormality may be an important factor in the development of major depressive disorder (MDD). Various polymorphisms of the MAOA gene have been investigated for possible associations with mood disorders, but results have been inconsistent. The goal of the present study was to investigate whether polymorphisms of the MAOA gene are associated with MDD or alternatively with different clinical subgroups of MDD. A total of 590 Han Chinese subjects in Taiwan (312 controls and 278 MDD patients) were recruited. Among the males, there were no associations with MAOA polymorphisms. Among the females, an association was found between MAOA polymorphisms and severe MDD (P=0.041 for uVNTR and 0.017 for EcoRV (rs1137070), respectively). However, in analyses of haplotype frequencies and multiple logistic regression, MAOA polymorphisms were not associated with either MDD or its subgroups. The results suggest that MAOA polymorphisms do not play a major role in the pathogenesis of MDD or its subgroups. However, a potential role for a minor association with some specific subgroups and with different ethnic samples needs to be explored further.

The interleukin-6, serotonin transporter, and monoamine oxidase A genes and endurance performance during the South African Ironman Triathlon

Previous studies have identified an association of genetic variants believed to alter physiological and biochemical processes locally within the skeletal muscle and therefore performance in the Ironman triathlon. There is growing evidence that the serotonergic system and circulating interleukin (IL)-6 levels are also involved in mediating endurance capacity. Investigators have demonstrated that recombinant human IL-6 administration and serotonergic neurotransmission manipulation, with 5-hydroxytryptamine transporter (5-HTT) and monoamine oxidase A (MAO-A) inhibitors, prior to exercise, can alter running performance, consistent with a central governor hypothesis. The aim of this study was to investigate possible associations of functional polymorphisms within the IL-6, 5-HTT, and MAO-A genes with endurance performance of Ironman triathletes. Four hundred sixty-eight male Caucasian triathletes who completed the 2000 and (or) 2001 South African Ironman Triathlon and 200 healthy Caucasian male controls were genotyped for the -174 IL-6 G/C, 5-HTT 40 base pair (bp) insertion-deletion and 30 bp variable number of tandem repeats (VNTR) MAO-A gene polymorphisms. There were no significant differences in the relative genotype distributions within the IL-6 (p = 0.636), 5-HTT (p = 0.659), and MOA-A (p = 0.227) polymorphisms when the fastest-fnishing, middle-finishing, and slowest-finishing triathletes, as well as the control groups, were compared. There were no direct associations between the IL-6 -174 G/C, 5-HTT 44 bp insertion-deletion, and MAO-A 30 bp VNTR gene polymorphisms and endurance performance in the 2000 and (or) 2001 South African Ironman Triathlons. The neurogenetic basis of the central governor requires further investigation.

5-hydroxytryptamine signalling in irritable bowel syndrome with diarrhoea: effects of gender and menstrual status

BACKGROUND

Symptomatology and physiology differ between men and women and across the menstrual cycle in irritable bowel syndrome (IBS). Ovarian hormones influence 5-hydroxytryptamine (5-HT), an amine known to play a role in gut motor-sensory function.

AIM

To assess the effects of gender and menstrual status on platelet-depleted plasma (PDP) 5-HT concentration in IBS patients with diarrhoea (IBS-D) patients compared with healthy volunteers (HV).

METHODS

Platelet-depleted plasma 5-HT concentrations were assessed under fasting and fed conditions in 73 IBS-D patients (aged 18-58 years; 18 men) and 64 HV (aged 18-50 years; 24 men). Women were divided into those with low or high progesterone/oestrogen (P/O) levels.

RESULTS

Irritable bowel syndrome patients with diarrhoea had higher PDP 5-HT concentrations than HV under fasting (P = 0.002) and fed (P = 0.049) conditions. This was particularly related to IBS-D men having higher PDP 5-HT concentrations than healthy controls (P = 0.002). Moreover, PDP 5-HT concentrations in IBS-D women with low P/O levels were similar to healthy controls.

CONCLUSIONS

Similar to IBS-D women with high P/O levels, IBS-D men also have raised PDP 5-HT concentrations. 5-HT concentration normalizes at menses in IBS-D women, suggesting a shift in the mechanisms responsible for abnormal 5-HT signalling in these patients.

Sex-specific association between the 5-HTT gene-linked polymorphic region and basal cortisol secretion

OBJECTIVE

A key regulator of serotonergic neurotransmission is the serotonin transporter (5-HTT) and a common 5HTT gene promoter polymorphism, termed 5HTTLPR, is associated with phenotypes related to anxiety and depression. Furthermore, the serotonergic system influences hypothalamus-pituitary-adrenal (HPA) axis activity, which, in turn, is related to psychiatric diseases.

METHODS

To explore the association between the 5-HTTLPR and HPA axis regulation we performed a detailed endophenotyping in 216 healthy subjects (all 126 females used oral contraceptives).

RESULTS

While ACTH and cortisol responses to an established psychosocial stress paradigm (Trier Social Stress Test) were not found to be related to the 5-HTTLPR, we observed a significant and sex-specific association with the cortisol awakening response, which is a reliable marker of basal cortisol secretion, and with ACTH levels after dexamethasone administration. The supplementary inclusion of a 5-HTT A/G polymorphism (rs25531) in the analyses did not substantially modify our results.

CONCLUSION

These findings support the view that the 5-HTTLPR is associated with a major neuroendocrine stress system. It could be speculated that the sex-specific nature of this association contributes to the distinct gender differences in the vulnerability for depression.

Menopause alters the metabolism of serum serotonin precursors and their correlation with gonadotropins and estradiol

OBJECTIVE

Tryptophan, the serotonin (5-HT) precursor, is circulating in blood in both free (FT) and protein-bound forms. The free form crosses the hematoencephalic barrier and is converted into 5-HT. During the fertile years, tryptophan levels are negatively correlated to gonadotropin concentrations. The present study aims to evaluate the correlation between circulating tryptophan, gonadotropin and estradiol (E2) levels postmenopause.

METHODS

Serum levels of total tryptophan (TT, free + protein-bound) and FT, and plasma luteinizing hormone (LH), follicle stimulating hormone (FSH), and E2 were determined in 15 postmenopausal women and 15 cycling women during follicular (days 7-10), periovulatory (days 13-16) and luteal (days 21-24) phases of the menstrual cycle. Data were analyzed by ANOVA, linear correlation coefficients and hierarchical cluster analysis of variables.

RESULTS

TT, but not FT, levels were significantly (p<0.05) higher in postmenopausal (12.07+/-0.40 microg/ml) than fertile women in the periovulatory period (10.46+/-0.36 microg/ml). In postmenopausal women, there was no significant correlation between TT and FT, nor between these tryptophan forms and gonadotropins, but only between FT and E2. Cluster analysis showed that the main cluster composed by FSH-LH-TT-FT observed in fertile women was absent in postmenopause, since both serum tryptophan forms were distant from gonadotropins.

CONCLUSION

High TT levels circulate in postmenopausal women, with lack of correlation between TT and FT, and FT/TT and gonadotropins. Since estrogens play a pivotal role on central 5-HT metabolism, estrogen deprivation may alter the brain tryptophan utilization for 5-HT synthesis and its relation to gonadotropin release.

Protective actions of ovarian hormones in the serotonin system of macaques

The serotonin neurons of the dorsal and medial raphe nuclei project to all areas of the forebrain and play a key role in mood disorders. Hence, any loss or degeneration of serotonin neurons could have profound ramifications. In a monkey model of surgical menopause with hormone replacement and no neural injury, E and P decreased gene expression in the dorsal raphe nucleus of c-jun n-terminal kinase (JNK1) and kynurenine mono-oxygenase (KMO) that promote cell death. In concert, E and P increased gene expression of superoxide dismutase (SOD1), VEGF, and caspase inhibitory proteins that promote cellular resilience in the dorsal raphe nucleus. Subsequently, we showed that ovarian steroids inhibit pivotal genes in the caspase-dependent and caspase-independent pathways in laser-captured serotonin neurons including apoptosis activating factor (Apaf1), apoptosis-inducing factor (AIF) and second mitochondria-derived activator of caspases (Smac/Diablo). SOD1 was also increased specifically in laser-captured serotonin neurons. Examination of protein expression in the dorsal raphe block revealed that JNK1, phosphoJNK1, AIF and the translocation of AIF from the mitochondria to the nucleus decreased with hormone therapy, whereas pivotal execution proteins in the caspase pathway were unchanged. In addition, cyclins A, B, D1 and E were inhibited, which would prevent re-entry into the cell cycle and catastrophic death. These data indicated that in the absence of gross injury to the midbrain, ovarian steroids inhibit the caspase-independent pathway and cell cycle initiation in serotonin neurons. To determine if these molecular actions prevented cellular vulnerability or death, we examined DNA fragmentation in the dorsal raphe nucleus with the TUNEL assay (terminal deoxynucleotidyl transferase nick end labeling). Ovarian steroids significantly decreased the number of TUNEL-positive cells in the dorsal raphe. Moreover, TUNEL staining prominently colocalized with TPH immunostaining, a marker for serotonin neurons. In summary, ovarian steroids increase the cellular resilience of serotonin neurons and may prevent serotonin neuron death in women facing decades of life after menopause. The survival of serotonin neurons would support cognition and mental health.

Migraine in postmenopausal women and the risk of invasive breast cancer

BACKGROUND

The frequency of migraine headache changes at various times of a woman's reproductive cycle. Menarche, menses, pregnancy, and perimenopause may carry a different migraine risk conceivably because of fluctuating estrogen levels, and in general, migraine frequency is associated with falling estrogen levels. Given the strong relationship between endogenous estrogen levels and breast cancer risk, migraine sufferers may experience a reduced risk of breast cancer.

METHODS

We combined data from two population-based case-control studies to examine the relationship between migraine and risk of postmenopausal invasive breast cancer among 1,199 ductal carcinoma cases, 739 lobular carcinoma cases, and 1,474 controls 55 to 79 years of age. Polytomous logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

Women who reported a clinical diagnosis of migraine had reduced risks of ductal carcinoma (OR, 0.67; 95% CI, 0.54-0.82) and lobular carcinoma (OR, 0.68; 95% CI, 0.52-0.90). These associations were primarily limited to hormone receptor-positive tumors as migraine was associated with a 0.65-fold (95% CI, 0.51-0.83) reduced risk of estrogen receptor-positive (ER+)/progesterone receptor-positive (PR+) ductal carcinoma. The reductions in risk observed were seen among migraine sufferers who did and did not use prescription medications for their migraines.

CONCLUSIONS

These data suggest that a history of migraine is associated with a decreased risk of breast cancer, particularly among ER+/PR+ ductal and lobular carcinomas. Because this is the first study to address an association between migraine history and breast cancer risk, additional studies are needed to confirm this finding.

The anabolic androgenic steroid nandrolone decanoate affects mRNA expression of dopaminergic but not serotonergic receptors

The abuse of anabolic androgenic steroids (AASs) at supratherapeutic doses is a problem not only in the world of sports, but also among non-athletes using AASs to improve physical appearance and to become more bold and courageous. Investigations of the possible neurochemical effects of AAS have focused partially on the monoaminergic systems, which are involved in aggressive behaviours and the development of drug dependence. In the present study, we administered nandrolone decanoate (3 or 15 mg/kg/day for 14 days) and measured mRNA expression of dopaminergic and serotonergic receptors, transporters and enzymes in the male rat brain using quantitative real-time polymerase chain reaction. Expression of the dopamine D1-receptor transcript was elevated in the amygdala and decreased in the hippocampus while the transcript level of the dopamine D4-receptor was increased in the nucleus accumbens. No changes in transcriptional levels were detected among the serotonin-related genes examined in this study. The altered mRNA expression of the dopamine receptors may contribute to some of the behavioural changes often reported in AAS abusers of increased impulsivity, aggression and drug-seeking.

Tailoring treatment of depression for women across the reproductive lifecycle: the importance of pregnancy, vasomotor symptoms, and other estrogen-related events in psychopharmacology

Compared with men, women are at increased risk of depression, especially at several reproductive-related lifecycle points. This may be partially due to changing levels of estrogen, a hormone that can affect levels of neurotransmitters and neural proteins. As estrogen levels vary throughout the lifespan, risk of depression in women also varies, and not all treatments are appropriate or effective at all times. In adolescence, onset of depression may be associated with onset of puberty, but treating underage girls with antidepressants can risk suicidality. In females of childbearing age, mood disturbances associated with menstrual cycles signal a risk for later full-blown major depressive disorder. In depressed pregnant and postpartum women, risks of treatment versus risks of nontreatment are intricate and require case-by-case evaluation. In perimenopause, vasomotor symptoms may be harbingers of oncoming depression and also may signal the presence of dysregulated hormones and neurotransmitters. Relieving vasomotor symptoms may be a necessary dimension of treating depression. In postmenopause, response to selected antidepressants may depend on whether the patient is also taking hormone-replacement therapy. To attain optimal outcomes, modern psychopharmacologists must tailor treatment of depression to a woman's reproductive stage of life.

5-HTTLPR and gender moderate changes in negative affect responses to tryptophan infusion

Expression of the serotonin transporter is affected by the genotype of the 5-HTTLPR (short and long forms) as well as the genotype of the SNP rs25531 within this region. Based on the combined genotypes for these polymorphisms, we designated each allele as a high or low expressing allele according to established expression levels-resulting in HiHi, HiLo, & LoLo genotype groups for analysis. We evaluated effects of gender and the promoter genotype on induction of negative affect by intravenous infusion of L: -tryptophan (TRP). The protocol consisted of a day-1 sham saline infusion and a day-2 active TRP infusion. Models assessed 5-HTTLPR composite genotype and gender as predictors of change in ratings of negative emotion during TRP infusion. During sham infusion there were no significant changes from baseline in mood ratings. During TRP infusion all negative affect ratings increased significantly from baseline (P's < .02). The genotype x gender interaction was a significant predictor of depression-dejection (P = .013), and trended towards predicting anger-hostility (P = .084). Males in the HiHi group had greater increases in negative affect during infusion, compared to all groups except LoLo females, who also showed increased negative affect.

Current and prospective pharmacological targets in relation to antimigraine action

Migraine is a recurrent incapacitating neurovascular disorder characterized by unilateral and throbbing headaches associated with photophobia, phonophobia, nausea, and vomiting. Current specific drugs used in the acute treatment of migraine interact with vascular receptors, a fact that has raised concerns about their cardiovascular safety. In the past, alpha-adrenoceptor agonists (ergotamine, dihydroergotamine, isometheptene) were used. The last two decades have witnessed the advent of 5-HT(1B/1D) receptor agonists (sumatriptan and second-generation triptans), which have a well-established efficacy in the acute treatment of migraine. Moreover, current prophylactic treatments of migraine include 5-HT(2) receptor antagonists, Ca(2+) channel blockers, and beta-adrenoceptor antagonists. Despite the progress in migraine research and in view of its complex etiology, this disease still remains underdiagnosed, and available therapies are underused. In this review, we have discussed pharmacological targets in migraine, with special emphasis on compounds acting on 5-HT (5-HT(1-7)), adrenergic (alpha(1), alpha(2,) and beta), calcitonin gene-related peptide (CGRP(1) and CGRP(2)), adenosine (A(1), A(2), and A(3)), glutamate (NMDA, AMPA, kainate, and metabotropic), dopamine, endothelin, and female hormone (estrogen and progesterone) receptors. In addition, we have considered some other targets, including gamma-aminobutyric acid, angiotensin, bradykinin, histamine, and ionotropic receptors, in relation to antimigraine therapy. Finally, the cardiovascular safety of current and prospective antimigraine therapies is touched upon.

Headache and pregnancy

BACKGROUND

Many women who suffer from migraine and tension-type headaches (TTHs) have an improvement in the frequency of these headaches during pregnancy. At the same time pregnancy predisposes women to a number of potentially life-threatening conditions which can present with headache. Accurate diagnosis and treatment of headache during pregnancy is essential.

REVIEW SUMMARY

The primary objectives of this review are to: (1) Summarize the natural history of primary headache disorders, including migraine, tension-type, and cluster headaches during pregnancy, as well as the impact of migraine on pregnancy outcomes and complications.(2) Summarize the therapeutic options and strategies for managing headaches in pregnancy and (3) Discuss the causes of secondary headaches and the diagnostic evaluation for new onset headache during pregnancy.

CONCLUSION

Primary headache disorders, in particular TTHs and migraines, generally improve during pregnancy. However the frequency of improvement varies greatly. Because the pathophysiology of both migraines and TTHs is poorly understood, this limits our ability to predict improvement. Future research should be focused on headache pathophysiology and the effect of ovarian hormones and the pregnant state on headache pathogenesis.

The link between childhood trauma and depression: insights from HPA axis studies in humans

Childhood trauma is a potent risk factor for developing depression in adulthood, particularly in response to additional stress. We here summarize results from a series of clinical studies suggesting that childhood trauma in humans is associated with sensitization of the neuroendocrine stress response, glucocorticoid resistance, increased central corticotropin-releasing factor (CRF) activity, immune activation, and reduced hippocampal volume, closely paralleling several of the neuroendocrine features of depression. Neuroendocrine changes secondary to early-life stress likely reflect risk to develop depression in response to stress, potentially due to failure of a connected neural circuitry implicated in emotional, neuroendocrine and autonomic control to compensate in response to challenge. However, not all of depression is related to childhood trauma and our results suggest the existence of biologically distinguishable subtypes of depression as a function of childhood trauma that are also responsive to differential treatment. Other risk factors, such as female gender and genetic dispositions, interfere with components of the stress response and further increase vulnerability for depression. Similar associations apply to a spectrum of other psychiatric and medical disorders that frequently coincide with depression and are aggravated by stress. Taken together, this line of evidence demonstrates that psychoneuroendocrine research may ultimately promote optimized clinical care and help prevent the adverse outcomes of childhood trauma.

Differential effects of ovarian steroids and raloxifene on serotonin 1A and 2C receptor protein expression in macaques

To further understand the role of ovarian hormones in the function of the serotonin neural system, we investigated the effects of estradiol (E), progesterone (P), and raloxifene on 5HT 1A and 2C receptor protein expression in the dorsal raphe region using Western blot analysis. Adult rhesus macaques (Macaca mulatta) were ovariectomized (Ovx) and implanted with Silastic capsules containing E or P. In the first paradigm, animals that had been Ovx for 6-16 months were treated for 1 month with E (El) or E + P (EP1) and compared to animals that were untreated and Ovx for 5 months (n = 4 per group). In the second paradigm, comparisons were made between animals that were Ovx and untreated for 5 months, or Ovx and immediately implanted with Silastic capsules containing E or E + P for 5 months (E5, EP5), or administered raloxifene in the diet for 5 months (Ral5) (n = 4 per group). The dorsal raphe region was harvested, homogenized and a crude membrane fraction was obtained for examination of receptor proteins. In the first paradigm, 5HT1A receptor protein expression was significantly lower in E1 and EPI treatment groups compared to the Ovx-control group (ANOVA P = 0.01; posthoc P < 0.03), but 5HT2C receptor expression was unaffected by 1 month of E or EP treatment. In the second paradigm, there was no difference in 5HT1A receptor expression between the Ovx-control group and the E5 group, but 5HT1A receptor expression was significantly suppressed in the EP5 group (ANOVA P = 0.04; posthoc P < 0.05). In addition, 5HT2C expression increased in the E5 treatment group relative to the Ovx-control group. Addition of P to the E5 regimen prevented the E5-induced increase in 5HT2C receptor expression and significantly reduced 5HT2C receptor expression to a level below that observed in the Ovx-control group (ANOVA P = 0.001; posthoc P < 0.05). Thus, 5HT1A receptor may lose sensitivity to the suppressive effect of E after 5 months, whereas the 5HT2C receptor increases. However, addition of P in the EP5 regimen maintains the regulatory effects observed with 1 month of treatment. 5HT1A receptor protein levels were higher with raloxifene treatment than in Ovx-control animals (P < 0.01), suggesting that raloxifene may antagonize residual E in Ovx animals.

Reduced activity of monoamine oxidase in the rat brain following repeated nandrolone decanoate administration

Anabolic androgenic steroids (AAS) are known as doping agents within sports and body-building, but are currently also abused by other groups in society in order to promote increased courage and aggression. We previously showed that 14 days of daily intramuscular injections of the AAS nandrolone decanoate (15 mg/kg) reduced the extracellular levels of the dopaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the nucleus accumbens shell using microdialysis. The aim of the present study was to investigate whether the same dose regimen of nandrolone decanoate may affect the activities of the dopamine-metabolizing enzymes monoamine oxidases A and B (MAO-A and MAO-B). A radiometric assay was used to determine the activities of MAO-A and MAO-B in rat brain tissues after 14 days of daily i.m. nandrolone decanoate injections at the doses 3 and 15 mg/kg. Gene transcript contents of MAO-A, MAO-B and cathecol-O-methyltransferase (COMT) were measured with quantitative real-time reverse transcription PCR. 3 mg/kg of nandrolone decanoate significantly reduced the activity of both MAO-A and -B in the caudate putamen. 15 mg/kg of nandrolone decanoate significantly reduced the activity of MAO-A in the amygdala and increased the gene transcript level of MAO-B in the substantia nigra. In conclusion, imbalanced MAO activities may contribute to explain the impulsive and aggressive behaviour often described in AAS abusers. The reduced MAO activities observed are in line with our previously presented findings of decreased extracellular levels of DOPAC and HVA in the rat brain, indicating decreased monoaminergic activity following repeated AAS administration.

[Migraine and hormones: what can we be certain of?]

Women suffer from migraine far more frequently than men. This sex difference during the reproductive years is considered to result from additional trigger factors, such as the fluctuating hormones of the menstrual cycle and with the reproductive milestones of women. The role of the female hormones on migraine is illustrated by the phenomenon of menstrual migraine, and the changes in the clinical course of migraine with menarche, pregnancy, menopause and the external application of hormones. In summary, epidemiological, clinical and experimental studies document a substantial influence of female sex hormones on the pathophysiology of migraine headache.

Genes implicated in serotonergic and dopaminergic functioning predict BMI categories

OBJECTIVE

This study addressed the hypothesis that variation in genes associated with dopamine function (SLC6A3, DRD2, DRD4), serotonin function (SLC6A4, and regulation of monoamine levels (MAOA) may be predictive of BMI categories (obese and overweight + obese) in young adulthood and of changes in BMI as adolescents transition into young adulthood. Interactions with gender and race/ethnicity were also examined.

METHODS AND PROCEDURES

Participants were a subsample of individuals from the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative sample of adolescents followed from 1995 to 2002. The sample analyzed included a subset of 1,584 unrelated individuals with genotype data. Multiple logistic regressions were conducted to evaluate the associations between genotypes and obesity (BMI > 29.9) or overweight + obese combined (BMI > or = 25) with normal weight (BMI = 18.5-24.9) as a referent. Linear regression models were used to examine change in BMI from adolescence to young adulthood.

RESULTS

Significant associations were found between SLC6A4 5HTTLPR and categories of BMI, and between MAOA promoter variable number tandem repeat (VNTR) among men and categories of BMI. Stratified analyses revealed that the association between these two genes and excess BMI was significant for men overall and for white and Hispanic men specifically. Linear regression models indicated a significant effect of SLC6A4 5HTTLPR on change in BMI from adolescence to young adulthood.

DISCUSSION

Our findings lend further support to the involvement of genes implicated in dopamine and serotonin regulation on energy balance.

From menarche to menopause: exploring the underlying biology of depression in women experiencing hormonal changes

Epidemiologic data consistently report an elevated prevalence of major depressive disorder (MDD) in women. This increase begins during adolescence and continues through the menopausal transition. Population-based clinical studies report an increase in the incidence of MDD during perimenopause compared to either the premenopausal or postmenopausal period. Evidence suggests that fluctuations and decline of hormonal levels are correlated with this observed increase in risk for MDD. A strong predictor of depression in the perimenopausal period is a previous history of MDD. However, recent studies revealed an increased risk of new onset depression in perimenopausal women without a history of MDD. Additionally, recent reports have indicated that the presence of vasomotor symptoms may be associated with an increased the risk for MDD. The objective of this paper is to review evidence that would support our hypothesis that neurotransmitter systems are affected by changes in hormonal status over the course of a woman's life, leading to increase vulnerability to perimenopausal depression. Relevant data from nonclinical experiments will be discussed in the context of observed clinical evidence of the risk for MDD before, during, and after the menopausal transition. A testable hypothesis will be proposed to advance our understanding of hormonal effects on mood.

Neuroactive properties of reproductive steroids

Migraine is 3 times more common in postpubertal women than in men. Migraine is frequently exacerbated perimenstrually and commonly occurs exclusively at that time. It is often benefited by pregnancy and menopause. Estrogen withdrawal has been implicated as a mechanism for triggering migraines. The mechanism, however, is not well understood. Reproductive steroids have neuroactive properties that can modulate neuronal morphology and physiology. Increasing evidence suggests that circulating reproductive steroid levels regulate the balance of neuroexcitatory and neuroinhibitory activities in some brain regions by influencing synaptic plasticity. Estrogen has neuroexcitatory, whereas progesterone has neuroinhibitory, effects in most preclinical and clinical models. Several neurotransmitter systems that are implicated in migraine vary with reproductive steroid levels during the reproductive cycle. Estrogen stabilization may provide effective treatment in susceptible women, especially for catamenially exacerbated migraine.

Effects of environmental stress and gender on associations among symptoms of depression and the serotonin transporter gene linked polymorphic region (5-HTTLPR)

The short (s) variant of the serotonin transporter (5-HTT) gene linked functional polymorphic region (5-HTTLPR) is associated with depression. Stressful life events, gender, and race have been shown to moderate this association. We examined the relationship between 5-HTTLPR genotype and symptoms of depression in two samples. Study 1 = 288 participants from a study of caregiver stress; and Study 2 = 142 participants from a study examining psychosocial stressors, genetics, and health. Main effects of 5-HTTLPR on symptoms of depression were examined, along with moderation by stress (caregiving status or low childhood socioeconomic status (SES), gender, and race. The 5-HTTLPR x stress group x gender interaction was significant in both samples (P < 0.003, and P < 0.008, respectively). For females, the s allele, combined with caregiving stress (Study 1) or low childhood SES (Study 2), was associated with higher depression scores as compared to participants in the non-stressor group and those with the long (l) allele; whereas, in males, the l allele, combined with a stressor, was associated with higher depression scores as compared to those in the non-stressor group and those with the s allele. Findings from two independent samples suggest that the association of 5-HTTLPR with depression varies according to gender and stressful life events.

A pharmacogenomic evaluation of migraine therapy

Migraine is a common idiopathic primary headache disorder with significant mental, physical and social health implications. Accompanying an intense unilateral pulsating head pain other characteristic migraine symptoms include nausea, emesis, phonophobia, photophobia and in approximately 20-30% of migraine cases, neurologic disturbances associated with the aura phase. Although selective serotonin (5-HT) receptor agonists (i.e., 5-HT(1B/1D)) are successful in alleviating migrainous symptoms in < or = 70% of known sufferers, for the remaining 30%, additional migraine abortive medications remain unsuccessful, not tested or yet to be identified. Genetic characterization of the migrainous disorder is making steady progress with an increasing number of genomic susceptibility loci now identified on chromosomes 1q, 4q, 5q, 6p, 11q, 14q, 15q, 17p, 18q, 19p and Xq. The 4q, 5q, 17p and 18q loci involve endophenotypic susceptibility regions for various migrainous symptoms. In an effort to develop individualized pharmacotherapeutics, the identification of these migraine endophenotypic loci may well be the catalyst needed to aid in this goal. In this review the authors discuss the present treatment of migraine, known genomic susceptibility regions and results from migraine (genetic) association studies. The authors also discuss pharmacogenomic considerations for more individualized migraine prophylactic treatments.