Differential response to estrogen challenge test in women with and without premenstrual dysphoria

The transcription factor VAX1 in VIP neurons of the suprachiasmatic nucleus impacts circadian rhythm generation, depressive-like behavior, and the reproductive axis in a sex-specific manner in mice

Background

The suprachiasmatic nucleus (SCN) within the hypothalamus is a key brain structure required to relay light information to the body and synchronize cell and tissue level rhythms and hormone release. Specific subpopulations of SCN neurons, defined by their peptide expression, regulate defined SCN output. Here we focus on the vasoactive intestinal peptide (VIP) expressing neurons of the SCN. SCN VIP neurons are known to regulate circadian rhythms and reproductive function.

Methods

To specifically study SCN VIP neurons, we generated a novel knock out mouse line by conditionally deleting the SCN enriched transcription factor, Ventral Anterior Homeobox 1 (Vax1), in VIP neurons (Vax1Vip; Vax1fl/fl:VipCre).

Results

We found that Vax1Vip females presented with lengthened estrous cycles, reduced circulating estrogen, and increased depressive-like behavior. Further, Vax1Vip males and females presented with a shortened circadian period in locomotor activity and ex vivo SCN circadian period. On a molecular level, the shortening of the SCN period was driven, at least partially, by a direct regulatory role of VAX1 on the circadian clock genes Bmal1 and Per2. Interestingly, Vax1Vip females presented with increased expression of arginine vasopressin (Avp) in the paraventricular nucleus, which resulted in increased circulating corticosterone. SCN VIP and AVP neurons regulate the reproductive gonadotropin-releasing hormone (GnRH) and kisspeptin neurons. To determine how the reproductive neuroendocrine network was impacted in Vax1Vip mice, we assessed GnRH sensitivity to a kisspeptin challenge in vivo. We found that GnRH neurons in Vax1Vip females, but not males, had an increased sensitivity to kisspeptin, leading to increased luteinizing hormone release. Interestingly, Vax1Vip males showed a small, but significant increase in total sperm and a modest delay in pubertal onset. Both male and female Vax1Vip mice were fertile and generated litters comparable in size and frequency to controls.

Conclusion

Together, these data identify VAX1 in SCN VIP neurons as a neurological overlap between circadian timekeeping, female reproduction, and depressive-like symptoms in mice, and provide novel insight into the role of SCN VIP neurons.

Estrogen levels, emotion regulation, and emotional symptoms of women with premenstrual dysphoric disorder: The moderating effect of estrogen receptor 1α polymorphism

BACKGROUND

This study evaluated the association between estrogen levels, emotion regulation, depression, anxiety, and stress of women with premenstrual dysphoric disorder (PMDD). We also evaluated the moderating effect of estrogen receptor (ESR) α-Xbal polymorphism on the aforementioned association.

METHODS

A total of 100 women were diagnosed with PMDD based on psychiatric interviews and a prospective investigation of 3 menstrual cycles. A total of 96 normal individuals were recruited as controls. Their estrogen levels, depression, anxiety, stress, and ESR α-Xbal polymorphism in both premenstrual and follicular phases were assessed, and these data were included in the final analysis.

RESULTS

The PMDD group had high depression, anxiety, and stress and low emotional adjusting and tolerating in the premenstrual phase. Emotional adjustment was negatively associated with depression, anxiety and stress. No association was observed between PMDD and estrogen level. However, premenstrual estrogen level was negatively correlated with anxiety and stress in women with PMDD. The association was only significant in G carriers of ESR α-Xbal, as was the difference in premenstrual emotion regulation between the PMDD and control groups.

CONCLUSIONS

The results demonstrate the association between estrogen and anxiety in PMDD, supporting the claim that women with PMDD differ in their responses to normal estrogen levels. Furthermore, this association and dysfunctional emotional regulation in PMDD existed only among the G carriers of ESR α-Xbal polymorphism. Future studies should investigate the effect of estrogen on brain functions involving emotional regulation in women with PMDD, stratified by ESR α-Xbal polymorphism.

Women with Premenstrual Dysphoria Lack the Seemingly Normal Premenstrual Right-Sided Relative Dominance of 5-HTP-Derived Serotonergic Activity in the Dorsolateral Prefrontal Cortices - A Possible Cause of Disabling Mood Symptoms

Study Objective

To investigate potential quantitative and qualitative differences in brain serotonergic activity between women with Premenstrual Dysphoria (PMD) and asymptomatic controls.

Background

Serotonin-augmenting drugs alleviate premenstrual mood symptoms in the majority of women with PMD while serotonin-depleting diets worsen PMD symptoms, both indicating intrinsic differences in brain serotonergic activity in women with PMD compared to asymptomatic women.

Methods

Positron-emission tomography with the immediate precursor of serotonin, 5-hydroxytryptophan (5-HTP), radiolabelled by ¹¹C in the beta-3 position, was performed in the follicular and luteal phases for 12 women with PMD and 8 control women. Brain radioactivity–a proxy for serotonin precursor uptake and synthesis–was measured in 9 regions of interest (ROIs): the right and left sides of the medial prefrontal cortex, dorsolateral prefrontal cortex, putamen and caudate nucleus, and the single “whole brain”.

Results

There were no significant quantitative differences in brain 5-HTP-derived activity between the groups in either of the menstrual phases for any of the 9 ROIs. However, multivariate analysis revealed a significant quantitative and qualitative difference between the groups. Asymptomatic control women showed a premenstrual right sided relative increase in dorsolateral prefrontal cortex 5-HTP derived activity, whereas PMD women displayed the opposite (p = 0.0001). Menstrual phase changes in this asymmetry (premenstrual—follicular) correlated with changes in self ratings of ‘irritability’ for the entire group (r_s = -0.595, p = 0.006). The PMD group showed a strong inverse correlation between phase changes (premenstrual—follicular) in plasma levels of estradiol and phase changes in the laterality (dx/sin) of radiotracer activity in the dorsolateral prefrontal ROI (r_s = -0.635; 0.027). The control group showed no such correlation.

Conclusion

Absence of increased premenstrual right-sided relative 5-HTP-derived activity of the dorsolateral prefrontal cortices was found to strongly correlate to premenstrual irritability. A causal relationship here seems plausible, and the findings give further support to an underlying frontal brain disturbance in hormonally influenced serotonergic activity in women with PMD. Because of the small number of subjects in the study, these results should be considered preliminary, requiring verification in larger studies.

Ovarian morphology in premenstrual dysphoria

Ovarian cyclicity is a prerequisite for premenstrual dysphoria (PMD), as illustrated by the fact that this condition is effectively eliminated by ovariectomy or by treatment with a GnRH agonist. Despite the possibility of differences in ovarian function between women with and without PMD, no study comparing ovarian morphology in these two groups has ever been published. Fifty-two women were recruited for this study; 26 had premenstrual dysphoria, fulfilling criteria slightly modified from those of the premenstrual dysphoric disorder, and 26 were asymptomatic age-matched controls. Ovarian morphology was assessed using transvaginal 7 MHz ultrasonography on day 5 after the start of menses, and venous blood was sampled for hormone analysis on days 3 and 8, the expected day of ovulation, and day -4 of the menstrual cycle. There were no significant differences between the groups with respect to the prevalence of polycystic ovaries (PCO), the total number of follicles, the total ovarian volume or serum levels of androgen hormones. In addition, serum free testosterone levels in late premenstrual phase showed an inverse association to premenstrual symptoms of irritability and a similar inverse association trend to symptoms of depressed mood. Unexpectedly, the prevalence of ovaries with fewer than five antral or growing follicles was significantly higher in women with PMD than in controls (p=0.016). While the results do not support a role for PCO or androgen hormones in eliciting late luteal phase irritability, the possible relationship between oligofollicular ovaries and PMD deserves further study.

Approach to premenstrual dysphoria for the mental health practitioner

As many as 7% of women experience significant social or occupational dysfunction as a result of severe premenstrual mood disturbance. Biological, psychological, and sociocultural factors are implicated in the cause of premenstrual dysphoric disorder, but the interaction between these factors remains to be elucidated. Mental health practitioners can aid women by providing diagnostic clarity and by initiating an integrated step-wise management approach.

Understanding and treating premenstrual dysphoric disorder: an update for the women's health practitioner

Up to 7% of women report premenstrual symptoms severe enough to impair daily function, and are said to suffer from premenstrual dysphoric disorder (PMDD). Although PMDD is predominately regarded as a biologically based condition, sociocultural factors, and particularly life stress, past sexual abuse, and cultural socialization, likely interact with hormonal changes. This integrative model has implications for etiology and treatment of PMDD.

Evaluation of different add-back estradiol and progesterone treatments to gonadotropin-releasing hormone agonist treatment in patients with premenstrual dysphoric disorder

OBJECTIVE

The aim of this study was to investigate which add-back hormone replacement therapy would be most beneficial in terms of mood effects for patients with premenstrual dysphoric disorder who are receiving gonadotropin-releasing hormone agonist therapy.

STUDY DESIGN

Three different add-back hormone replacement treatments were evaluated in a randomized, double-blinded, cross-over clinical trial in 27 patients premenstrual dysphoric disorder. The add-back treatments consisted of 1.5 mg estradiol and 400 mg progesterone, 1.5 mg estradiol and placebo, and 0.5 mg estradiol and 400 mg progesterone. The primary outcome measure was daily symptom ratings for mood and physical symptoms.

RESULTS

The highest dose of estradiol in combination with progesterone was associated with the most pronounced symptom recurrence, both in comparison with a lower dose of estradiol together with progesterone and estradiol-only treatment.

CONCLUSION

Based on the findings of the present study, long-cycle add-back treatment to avoid frequent progestagen use appears to be most beneficial for patients with premenstrual dysphoric disorder.

Potential hormonal mechanisms of attention-deficit/hyperactivity disorder and major depressive disorder: a new perspective

Hormonal influences on the organization of behavior are apparent to neuroendocrinologists but under-examined in relation to childhood and adolescent mental disorders. A central mystery in the field of developmental psychopathology is the preferential male vulnerability to behavior disorders in childhood and female vulnerability to emotional disorders in adolescence. Relative neglect of a hormonal explanation may be due to lack of simple or unifying conceptual paradigms to guide studies. This paper seeks to stimulate research in this area by drawing upon clinical psychology and neuroscience literatures to offer a heuristic paradigm for clinical research. Two syndromes are selected here for illustration: Attention-Deficit/Hyperactivity Disorder (ADHD) and Major Depressive Disorder (MDD), because they have opposite gender risk profiles. Two guiding theories are evaluated. First, prenatal organizational effects of testosterone may modulate striatally-based dopaminergic circuits in such a way as to place boys at greater risk for early developing inattention and disruptive behavioral disorders. Second, activational effects of estradiol at puberty may modulate amygdalar and other circuitry, with particular effects on serotonergic pathways, in such a way as to place girls at greater risk for internalizing and mood disorders. Hypotheses from these theories are evaluated based on the current available literature, and limitations of, and future directions for, this literature are discussed.

Neurobehavioral impact of menopause on mood

The menopausal transition is a time of risk for mood change ranging from distress to minor depression to major depressive disorder in a vulnerable subpopulation of women in the menopausal transition. Somatic symptoms have been implicated as a risk factor for mood problems, although these mood problems have also been shown to occur independently of somatic symptoms. Mood problems have been found to increase in those with a history of mood continuum disorders, but can also occur de novo as a consequence of the transition. Stress has been implicated in the etiology and the exacerbation of these mood problems. Estrogen and add-back testosterone have both been shown to positively affect mood and well-being. In most cases, the period of vulnerability to mood problems subsides when the woman's hormonal levels stabilize and she enters full menopause.

Luteal-phase accentuation of acoustic startle response in women with premenstrual dysphoric disorder

Alterations in central nervous system response to menstrual cycle-related fluctuations in neuroactive steroids are thought to underlie the emergence of negative affect in the luteal phase of the menstrual cycle in women with premenstrual dysphoric disorder (PMDD). Such changes in the neuroendocrine milieu may lead to heightened arousal and response to stress in women with PMDD. Using the acoustic startle paradigm, we sought to determine whether women with PMDD have an accentuated physiologic response to a mildly aversive stimulus during the luteal compared to follicular phase. Further, we also examined the impact of visual affective stimuli on acoustic startle response (ASR) magnitude. During the follicular and luteal phases of the menstrual cycle, acoustic stimuli (103 dB) were delivered to 15 women with PMDD and 14 healthy menstruating women of similar age. After obtaining baseline ASR, the procedure was repeated when subjects viewed pleasant, neutral and unpleasant pictures. There was a significant group by menstrual cycle phase interaction for baseline ASR magnitude, which can be attributed to the heightened startle magnitude in women with PMDD compared to healthy women during the luteal relative to the follicular phase. The direction and degree to which picture viewing modulated the startle magnitude did not vary by group or menstrual cycle phase. These data suggest that menstrual cycle phase has a powerful modulatory effect on physiologic reactivity in women with PMDD but not in healthy women. Physiologic response to affective stimuli appears to be intact in women with PMDD across the menstrual cycle.