Sex hormones affect neurotransmitters and shape the adult female brain during hormonal transition periods

Revisiting the role of sexual hormones in the demyelinated central nervous system

Sex-related differences characterize multiple sclerosis, an autoimmune, inflammatory and neurodegenerative disease displaying higher incidence in females as well as discrepancies in susceptibility and progression. Besides clinical specificities, molecular and cellular differences related to sex hormones were progressively uncovered improving our understanding of the mechanisms involved in this disabling disease. The most recent findings may give rise to the identification of novel therapeutic perspectives that could meet the urgent need for a treatment preventing the transition from the recurrent- to the progressive form of the disease. The present review is an update of our current knowledge about progestagens, androgens and estrogens in the context of CNS demyelination including their synthesis, the impact of their dysregulation, the preclinical and clinical data presently available, the main molecular dimorphisms related to these hormones and their age-related changes and relationship with failure of spontaneous remyelination, likely impacting the inexorable progression of multiple sclerosis towards irreversible disabilities.

Exploring the role of sex hormones and gender diversity in multiple sclerosis

Sex and sex hormones are thought to influence multiple sclerosis (MS) through effects on inflammation, myelination and neurodegeneration, and exogenous hormones have been explored for their therapeutic potential. However, our understanding of how sex hormones influence MS disease processes and outcomes remains incomplete. Furthermore, our current knowledge is derived primarily from studies that focus exclusively on cisgender populations with exclusion of gender-diverse people. Gender-affirming hormone therapy comprising exogenous sex hormones or sex hormone blocking agents are commonly used by transgender and gender-diverse individuals, and it could influence MS risk and outcomes at various stages of disease. A better understanding of the impact and potential therapeutic effects of both endogenous and exogenous sex hormones in MS is needed to improve care and outcomes for cisgender individuals and, moreover, for gender-diverse populations wherein an evidence base does not exist. In this Perspective, we discuss the effects of endogenous and exogenous sex hormones in MS, including their potential therapeutic benefits, and examine both established sex-based dimorphisms and the potential for gender-diverse dimorphisms. We advocate for future research that includes gender-diverse people to enhance our knowledge of the interplay of sex and sex hormones in MS, leading to the development of more effective and inclusive treatment strategies and improvement of care for all individuals with MS.

Women's perceptions of biological causes and potentials of genomic risk markers in postpartum depression: A qualitative study

INTRODUCTION

Postpartum depression affects 10-15% of women. Novel evidence suggests that genomic markers for enhanced sensitivity to estradiol signaling may help identify women at high risk of postpartum depression. We explored the women's perceptions of testing for genomic risk markers for developing postpartum depression.

METHODS

We conducted semi-structured interviews with 13 Danish women who had a history of postpartum depression using a phenomenological approach. A transdisciplinary group of researchers analyzed the interviews thematically. Through the concept of potentiality, we unfolded the women's perceptions regarding testing for genomic risk markers for postpartum depression.

RESULTS

We identified three key themes. 1) Biology as a contributing factor to postpartum depression. Only a few women thought postpartum depression could be related to a sensitivity to hormonal changes. 2) The role of external events in making sense of postpartum depression. Most women perceived their postpartum depression as primarily triggered by external factors rather than biological factors. 3) The ambiguous potentiality of testing for genomic risk markers of postpartum depression. Testing for genomic risk markers was envisioned by some women as having the potential to prevent postpartum depression and reduce stigma. Yet, at the same time, knowing their risk was perceived as holding the potential to induce depressive symptoms.

CONCLUSION

We found that to some women, knowledge about genomic risk markers introduced hope regarding possible prevention and, at the same time, it introduced concerns about inducing depressive symptoms. We suggest considering such perceptions if implementing new genomic risk marker technologies in risk profiling.

Association of metalloestrogens exposure with depression in women across reproductive lifespan

Background

Exposure to metal could impact women's depression risk. However, the connection and mechanisms between metalloestrogens exposure and depression are still not fully understood. We aim to explore the associations between metalloestrogens and the risk of depression in women across reproductive lifespan.

Methods

Using data from NHANES 2011-2018, we employed logistic regression and baknernel machine regression (BKMR) to study links between metalloestrogen exposure and depression in US women. We analyzed how contraceptive use affects this relationship.

Results

The study involved 3,374 adult women, with 345 of them experiencing depression. Our research revealed that certain metalloestrogens like Ba, Ca, Pb, Sb, and Sn were linked to higher depression risk in women, while Hg was associated with lower depression risk in older women. For women aged 18-44, a blend of metalloestrogens showed a significant positive correlation with depression risk, and the likelihood of depression in later years notably rose when the metal mixture concentration reached or exceeded the 60th percentile. Oral contraceptives would have an effect on the impact of metalloestrogen mixture exposure on depression in women during the reproductive stage.

Conclusions

Our study indicates a significant link between metalloestrogen exposure and a higher risk of depression in adult women in the United States. This finding can aid in identifying the connection and enhancing women's mental well-being.

Effects of dopamine receptor antagonists and radiation on mouse neural stem/progenitor cells

BACKGROUND

Dopamine receptor antagonists have recently been identified as potential anti-cancer agents in combination with radiation, and a first drug of this class is in clinical trials against pediatric glioma. Radiotherapy causes cognitive impairment primarily by eliminating neural stem/progenitor cells and subsequent loss of neurogenesis, along with inducing inflammation, vascular damage, and synaptic alterations. Here, we tested the combined effects of dopamine receptor antagonists and radiation on neural stem/progenitor cells.

METHODS

Using transgenic mice that report the presence of neural stem/progenitor cells through Nestin promoter-driven expression of EGFP, the effects of dopamine receptor antagonists alone or in combination with radiation on neural stem/progenitor cells were assessed in sphere-formation assays, extreme limiting dilution assays, flow cytometry and real-time PCR in vitro and in vivo in both sexes.

RESULTS

We report that hydroxyzine and trifluoperazine exhibited sex-dependent effects on murine newborn neural stem/progenitor cells in vitro. In contrast, amisulpride, nemonapride, and quetiapine, when combined with radiation, significantly increased the number of neural stem/progenitor cells in both sexes. In vivo, trifluoperazine showed sex-dependent effects on adult neural stem/progenitor cells, while amisulpride demonstrated significant effects in both sexes. Further, amisulpride increased sphere forming capacity and stem cell frequency in both sexes when compared to controls.

CONCLUSION

We conclude that a therapeutic window for dopamine receptor antagonists in combination with radiation potentially exists, making it a novel combination therapy against glioblastoma. Normal tissue toxicity following this treatment scheme likely differs depending on age and sex and should be taken into consideration when designing clinical trials.

Antipsychotic-induced prolactin elevation in premenopausal women with schizophrenia: associations with estrogen, disease severity and cognition

PURPOSE

Antipsychotic-induced prolactin elevation may impede protective effects of estrogens in women with schizophrenia-spectrum disorders (SSD). Our study sought to confirm whether the use of prolactin-raising antipsychotics is associated with lower estrogen levels, and to investigate how estrogen and prolactin levels relate to symptom severity and cognition in premenopausal women with SSD.

METHODS

This cross-sectional study included 79 premenopausal women, divided in three groups of women with SSD treated with prolactin-sparing antipsychotics (n = 21) or prolactin-raising antipsychotics (n = 27), and age-matched women without SSD (n = 31). Circulating 17β-estradiol was compared among groups. In patients, we assessed the relationship between prolactin and 17β-estradiol, and the relationships of these hormones to symptom severity and cognition, using correlation analyses and backward regression models.

RESULTS

In women receiving prolactin-raising antipsychotics, 17β-estradiol levels were lower as compared to both other groups (H(2) = 8.34; p = 0.015), and prolactin was inversely correlated with 17β-estradiol (r=-0.42, p = 0.030). In the prolactin-raising group, 17β-estradiol correlated positively with verbal fluency (r = 0.52, p = 0.009), and 17β-estradiol and prolactin together explained 29% of the variation in processing speed (β17β-estradiol = 0.24, βprolactin = -0.45, F(2,25) = 5.98, p = 0.008). In the prolactin-sparing group, 17β-estradiol correlated negatively with depression/anxiety (r = -0.57, p = 0.014), and together with prolactin explained 26% of the variation in total symptoms (β17β-estradiol = -0.41, βprolactin = 0.32, F(2,18) = 4.44, p = 0.027).

CONCLUSIONS

In women with SSD, antipsychotic-induced prolactin elevation was related to lower estrogen levels. Further, estrogens negatively correlated with symptom severity and positively with cognition, whereas prolactin levels correlated negatively with cognition. Our findings stress the clinical importance of maintaining healthy levels of prolactin and estrogens in women with SSD.

Cooperative nuclear action of RNA-binding proteins PSF and G3BP2 to sustain neuronal cell viability is decreased in aging and dementia

Dysfunctional RNA-binding proteins (RBPs) have been implicated in several geriatric diseases, including Alzheimer's disease (AD). However, little is known about the nuclear molecular actions and cooperative functions mediated by RBPs that affect gene regulation in sporadic AD or aging. In the present study, we investigated aging- and AD-associated changes in the expression of PSF and G3BP2, which are representative RBPs associated with sex hormone activity. We determined that both PSF and G3BP2 levels were decreased in aged brains compared to young brains of mice. RNA sequencing (RNA-seq) analysis of human neuronal cells has shown that PSF is responsible for neuron-specific functions and sustains cell viability. In addition, we showed that PSF interacted with G3BP2 in the nucleus and stress granules (SGs) at the protein level. Moreover, PSF-mediated gene regulation at the RNA level correlated with G3BP2. Interestingly, PSF and G3BP2 target genes are associated with AD development. Mechanistically, quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis demonstrated that the interaction of RBPs with the pre-mRNA of target genes enhanced post-transcriptional mRNA stability, suggesting a possible role for these RBPs in preserving neuronal cell viability. Notably, in the brains of patients with sporadic AD, decreased expression of PSF and G3BP2 in neurons was observed compared to non-AD patients. Overall, our findings suggest that the cooperative action of PSF and G3BP2 in the nucleus is important for preventing aging and AD development.

Impact of the estrous cycle on brain monoamines and behavioral and respiratory responses to CO2 in mice

The prevalence of panic disorder is two to four times higher in women compared to that in men, and hormonal changes during the menstrual cycle play a role in the occurrence of panic attacks. Here, we investigated the effect of the estrous cycle on the ventilatory and behavioral responses to CO2 in mice. Female mice in proestrus, estrus, metestrus, or diestrus were exposed to 20% CO2, and their escape behaviors, brain monoamines, and plasma levels of 17β-estradiol (E2) and progesterone (P4) were measured. Pulmonary ventilation (V̇E), oxygen consumption (V̇O2), and body core temperature (TB) were also measured during normocapnia followed by CO2. Females exposed to 20% CO2 exhibited an escape behavior, but the estrous cycle did not affect this response. Females in all phases of the estrous cycle showed higher V̇E and lower TB during hypercapnia. In diestrus, there was an attenuation of CO2-induced hyperventilation with no change in V̇O2, whereas in estrus, this response was accompanied by a reduction in V̇O2. Hypercapnia also increased the concentration of plasma P4 and central DOPAC, the main dopamine metabolite, in all females. There was an estrous cycle effect on brainstem serotonin, with females in estrus showing a higher concentration than females in the metestrus and diestrus phases. Therefore, our data suggest that hypercapnia induces panic-related behaviors and ventilatory changes that lead to an increase in P4 secretion in female mice, likely originating from the adrenals. The estrous cycle does not affect the behavioral response but interferes in the ventilatory and metabolic responses to CO2 in mice.

APOE4 and Chronic Health Risk Factors are Associated with Sex-Specific Preclinical Alzheimer's Disease Neuroimaging Biomarkers

Introduction

Two thirds of Alzheimer's disease (AD) patients are female. Genetic and chronic health risk factors for AD affect females more negatively compared to males.

Objective

This exploratory multimodal neuroimaging study aimed to examine sex differences in cognitively unimpaired older adults on: (1) amyloid-β via 18F-AV-45 Florbetapir PET imaging, (2) neurodegeneration via T1 weighted MRI volumetrics, (3) cerebral blood flow via ASL-MRI. We identified AD risk factors including genetic (APOE genotype status) and health markers (fasting glucose, mean arterial pressure, waist-to-hip ratio, and android and gynoid body fat) associated with neuroimaging outcomes for which we observed sex differences.

Methods

Participants were sedentary, amyloid-β positive older adults (N = 112, ages 65-87 years) without evidence of cognitive impairment (CDR = 0).

Results

Multivariate analysis of covariance models adjusted for intracranial volume, age, and years of education demonstrated lower volume (F (7, 102) = 2.67, p = 0.014) and higher blood flow F (6, 102) = 4.25, p =<0.001) among females compared to males in regions of interest connected to AD pathology and the estrogen receptor network. We did not observe sex differences in amyloid-β levels. Higher than optimal waist to hip ratio was most strongly associated with lower volume, while higher android fat percentage and APOE ε4 carrier status were most strongly associated with higher blood flow among female participants.

Discussion

Findings suggest genetic and chronic health risk factors are associated with sex-specific AD neuroimaging biomarkers. Underlying sex-specific biological pathways may explain these findings. Our results highlight the importance of considering sex differences in neuroimaging studies and when developing effective interventions for AD prevention and risk reduction.

Unveiling the Neurotransmitter Symphony: Dynamic Shifts in Neurotransmitter Levels during Menstruation

The menstrual cycle is an intricate biological process governed by hormonal changes that affect different facets of a woman's reproductive system. This review provides an overview of neurotransmitter alterations during different menstrual cycle phases and their effects on physiology and psychology. During the follicular phase, rising estrogen levels increase serotonin synthesis, enhancing mood, cognition, and pain tolerance. Estrogen may also influence dopamine levels, promoting motivation and reward sensitivity. GABA, involved in anxiety regulation, may be modulated by estrogen, inducing relaxation. Ovulation involves fluctuating dopamine and serotonin levels, potentially affecting motivation and positive mood. In the luteal phase, rising estrogen and progesterone may reduce serotonin availability, contributing to mood dysregulation, while enhanced GABAergic neurotransmission promotes sedation. Menstruation is characterized by declining estrogen and progesterone, potentially leading to mood disturbances, fluctuating GABAergic and dopaminergic neurotransmitter systems, relaxation, fatigue, motivation, and pleasure variations. Understanding neurotransmitter alterations during the menstrual cycle unveils the neurobiological mechanisms behind menstrual-related symptoms and disorders, facilitating targeted interventions. Pharmacological approaches targeting neurotransmitter systems, nutritional interventions, and lifestyle modifications show promise in managing menstrual symptoms. Future research should focus on further understanding neurotransmitter dynamics, personalized medicine, unexplored neurotransmitter roles, and integrating psychosocial factors. This knowledge will enhance well-being and quality of life for individuals experiencing menstrual-related challenges.

Sex Differences in the Neurobiology of Fear and Anxiety

Although women are diagnosed with anxiety and stress-related disorders at twice the rate of men, there remains a lack of clarity around how to enhance treatment within each sex to reduce disparate rates of anxiety. However, in recent years, a growing literature has identified neural, cognitive, and physiological mechanisms that contribute to sex differences in fear and anxiety, with the promise of informing tailored treatment approaches. Here, we review recent findings, focusing on human studies among healthy populations as well as among patients with generalized anxiety, social anxiety disorder, post-traumatic stress disorder, and panic disorder. The literature reveals nuanced differences in the types of stimuli that preferentially evoke anxiety and stress responses in women and men, as well as sex differences in threat neurocircuitry that mediates the behavioral, physiological, and subjective components of fear and anxiety.

Progestagens and progesterone receptor modulation: Effects on the brain, mood, stress, and cognition in females

Progesterone is a highly lipophilic gonadal hormone that can influence behavior and mental health through its receptors in the brain. Fluctuations in progesterone levels across critical periods of a females life are associated with increased susceptibility to mental conditions. This review highlights the effects of progestagens, including progesterone and synthetic progestins, on the brain, mood, stress, and cognition in females. The primary focus is on experimental pharmacological research that teases out the distinct effects of progestagens from those of estrogens. Additionally, the key literature on puberty, the menstrual cycle, pregnancy, perimenopause, hormonal contraceptives, and menopausal hormone therapy is reviewed, although conclusions are limited by the nested effects of progestagens and estrogens. Single study-findings suggest an influence of progesterone on amygdala reactivity related to processing of emotional stimuli and memory. In patients with premenstrual dysphoric disorder, progesterone receptor modulation improves premenstrual mood symptoms and potentially enhances fronto-cingulate control over emotion processing. The interaction between progestagens and the systems involved in the regulation of stress seems to influence subjective experiences of mood and stress. Sparse studies investigating the effects of progestin-only contraceptives suggest effects of progestagens on the brain, mood, and stress. Progesterone and progestins used for contraception can influence neural processes as myelination and neuroprotection, exerting protective effects against stroke. Concerning menopausal hormonal therapy, the effects of progestins are largely unknown. Levels of progesterone as well as type, administration route, timing, dose regimen, metabolism, and intracellular activity of progestins in hormonal contraceptives and menopausal hormonal therapy are factors whose effects remain to be elucidated. Altogether, current knowledge highlights the potential role of progestagens in females health but also calls for well-designed pharmaco-behavioral studies disentangling the effects of progestagens from those of estrogens.

Survey of patient experience and management of vasomotor symptoms due to menopause from the PatientsLikeMe community

OBJECTIVE

This study aimed to describe menopause and treatment experiences of women with vasomotor symptoms due to menopause in the United States.

METHODS

A cross-sectional survey was administered to women 40-65 years of age recruited from PatientsLikeMe, a dedicated online platform for patients.

RESULTS

A total of 196 women (mean age 55.7 years; 81.2% White) completed the survey and were included in the analyses. The majority (87.2%) reported experiencing bothersome symptoms; 54.3% (100/184) had daytime hot flashes, and 59.2% (109/184) had nighttime sweats and hot flashes, up to 5 times per day on average. Mean postmenopause duration was 10.8 years. Although most (68.5%, 126/184) reported having vasomotor symptoms for less than 5 years, some (14.1%, 26/184) had symptoms for more than a decade. Only 35.2% (69/196) were treated for their symptoms; the most frequently reported prescription treatment was hormone therapy (58%; 40/69), which was administered for less than 3 years in most cases (67.5%, 27/40). Although women were generally satisfied with their interactions with healthcare providers, 23.0% reported inadequate support. Sleep, personal relationships, and physical, emotional, and mental well-being were the most affected by vasomotor symptoms. Healthcare professionals with training in women's health were the most valued resource for dealing with the symptoms associated with menopause.

CONCLUSIONS

Not all women with symptoms were treated. In those whose concerns were addressed by providers, a reluctance to pursue treatment was still observed. A need persists to ensure that this population has the resources and support needed to effectively manage symptoms.

Sexual dimorphism, altered hippocampal glutamatergic neurotransmission, and cognitive impairment in APP knock-in mice

BACKGROUND

It is well established that glutamatergic neurotransmission plays an essential role in learning and memory. Previous studies indicate that glutamate dynamics shift with Alzheimer's disease (AD) progression, contributing to negative cognitive outcomes.

OBJECTIVE

In this study, we characterized hippocampal glutamatergic signaling with age and disease progression in a knock-in mouse model of AD (APPNL-F/NL--F).

METHODS

At 2-4 and 18+ months old, male and female APPNL/NL, APPNL-F/NL-F, and C57BL/6 mice underwent cognitive assessment using Morris water maze (MWM) and Novel Object Recognition (NOR). Then, basal and 70 mM KCl stimulus-evoked glutamate release was measured in the dentate gyrus (DG), CA3, and CA1 regions of the hippocampus using a glutamate-selective microelectrode in anesthetized mice.

RESULTS

Glutamate recordings support elevated stimulus-evoked glutamate release in the DG and CA3 of young APPNL-F/NL-F male mice that declined with age compared to age-matched control mice. Young female APPNL-F/NL-F mice exhibited increased glutamate clearance in the CA1 that slowed with age compared to age-matched control mice. Male and female APPNL-F/NL-F mice exhibited decreased CA1 basal glutamate levels, while males also showed depletion in the CA3. Cognitive assessment demonstrated impaired spatial cognition in aged male and female APPNL-F/NL-F mice, but only aged females displayed recognition memory deficits compared to age-matched control mice.

CONCLUSIONS

These findings confirm a sex-dependent hyper-to-hypoactivation glutamatergic paradigm in APPNL-F/NL-F mice. Further, data illustrate a sexually dimorphic biological aging process resulting in a more severe cognitive phenotype for female APPNL-F/NL-F mice than their male counterparts. Research outcomes mirror that of human AD pathology and provide further evidence of divergent AD pathogenesis between sexes.

Temporal dissociation between local and global functional adaptations of the maternal brain to childbirth: a longitudinal assessment

The maternal brain undergoes significant reorganization during birth and the postpartum period. However, the temporal dynamics of these changes remain unclear. Using resting-state functional magnetic resonance imaging, we report on local and global brain function alterations in 75 mothers in their first postpartum week, compared to 23 nulliparous women. In a subsample followed longitudinally for the next six months, we observed a temporal and spatial dissociation between changes observed at baseline (cluster mass permutation: pFWE < 0.05). Local activity and connectivity changes in widespread neocortical regions persisted throughout the studied time period (ANCOVAs vs. controls: pFDR < 0.05), with preliminary evidence linking these alterations to behavioral and psychological adaptations (interaction effect with postpartum time: uncorrected p < 0.05). In contrast, the initially reduced whole-brain connectivity of putamen-centered subcortical areas returned to control levels within six to nine weeks postpartum (linear and quadratic mixed linear models: pFDR < 0.05). The whole-brain spatial colocalization with hormone receptor distributions (Spearman correlations: pFDR < 0.05) and preliminary blood hormone associations (interaction effect with postpartum time: uncorrected p < 0.05) suggested that the postpartum restoration of progesterone levels may underlie this rapid normalization. These observations enhance our understanding of healthy maternal brain function, contributing to the identification of potential markers for pathological postpartum adaptation processes, which in turn could underlie postpartum psychiatric disorders.

Effect of exercise alone and in combination with time-restricted eating on cardiometabolic health in menopausal women

There is a need to investigate the effect of lifestyle modifications on cardiometabolic health-related issues that occur during menopause. The aim of this study was to compare the effect of resistance and endurance circuit training program alone (exercise group, n = 34) with the effect of time-restricted eating (16:8) combined with a training program (combination group, n = 28) on cardiometabolic health in 62 menopausal women (aged 51.3 ± 4.69 years). Testing was conducted before and after a 12-week period and included an assessment of body composition, glycemic control, lipid panel, blood pressure, and anthropometric measurements. Decreases in body mass index and systolic blood pressure were significantly greater in the combination group than in the exercise group (F(1,60) = 4.482, p = 0.038, η2 = 0.07; F(1,57) = 5.215, p = 0.026, η2 = 0.08, respectively, indicating moderate effects). There were significant decreases in fat mass (p = 0.001, r = 0.654), glucose level (p = 0.017, r = 0.459), insulin level (p = 0.013, r = 0.467), homeostatic model assessment for insulin resistance (p = 0.009, r = 0.499), waist circumference (p = 0.002, r = 0.596), and waist-to-height ratio (p = 0.003, r = 0.588) (indicating moderate effect) in the combination group, while there were no significant changes in the exercise group. There were no changes in lipid panel indicators in either group. This is the first study to investigate the effect of time-restricted eating combined with exercise in menopausal women. The results of the study provide evidence that the combination of time-restricted eating and exercise leads to a greater body mass index reduction than exercise alone in menopausal women.Trial registration: ClinicalTrials.gov, NCT06138015 registered 18 November 2023-Retrospectively registered, https://clinicaltrials.gov/study/NCT06138015 .

The influence of menstrual phase on synaptic plasticity induced via intermittent theta-burst stimulation

BACKGROUND

Ovarian hormones influence the propensity for short-term plasticity induced by repetitive transcranial magnetic stimulation (rTMS). Estradiol appears to enhance the propensity for neural plasticity. It is currently unknown how progesterone influences short-term plasticity induced by rTMS.

OBJECTIVE

The present research investigates whether the luteal versus follicular phase of the menstrual cycle influence short-term plasticity induced by intermittent theta-burst stimulation (iTBS). We tested the hypothesis that iTBS would increase motor evoked potentials (MEPs) during the follicular phase. Further, we explored the effects of the luteal phase on iTBS-induced neural plasticity.

METHOD

Twenty-nine adult females participated in a placebo-controlled study that delivered real and sham iTBS to the left primary motor cortex in separate sessions corresponding to the follicular phase (real iTBS), luteal phase (real iTBS), and a randomly selected day (sham iTBS). Outcomes included corticospinal excitability as measured by the amplitude of MEPs and short-interval intracortical inhibition (SICI) recorded from the right first dorsal interosseous muscle before and following iTBS (612 pulses).

RESULTS

MEP amplitude was increased following real iTBS during the follicular condition. No significant changes in MEP amplitude were observed during the luteal or sham visits. SICI was unchanged by iTBS irrespective of menstrual phase.

CONCLUSION

These findings suggest women experience a variable propensity for iTBS-induced short-term plasticity across the menstrual cycle. This information is important for designing studies aiming to induce plasticity via rTMS in women.

Current oral contraceptive use affects explicit and implicit measures of depression in women

Some data suggest that increased depressive symptoms may occur in women using combined oral contraceptives (OCs). However, this idea is controversial and the existing evidence is conflicting. The present study compared negative affect in 53 healthy women (M age = 19.9 years) during intervals of active daily OC hormone intake and during the washout week of the contraceptive cycle when no exogenous estrogens or progestins are used. A prospective counterbalanced repeated-measures study design was employed. Depressive affect was evaluated using standard psychometric tests of explicit (self-perceived) and implicit negative affect. Implicit measures are considered less subject to bias related to social expectations, self-awareness, or willingness to disclose. Other than their usual OCs, participants were medication-free and had been using OCs for a median of 12 mo. We found that measures of implicit affect (e.g., Affect Misattribution Procedure, Emotional Stroop Test) displayed a more depressive-like pattern of performance during active hormone intake, particularly among a subgroup of OC users who reported experiencing high levels of depressive affect more generally. In contrast, participants' self-perceptions suggested that they perceived their negative symptoms to be greater during the 'off' phase of the OC cycle, when OC steroids are withdrawn and menses occurs. The present findings reinforce the possibility of depressive mood effects associated with OC usage, and highlight the utility of including implicit measures, but also illustrate the complexity of mood assessment in OC users.

The Impact of Adverse Childhood Experiences on Cognitive Control Across the Lifespan: A Systematic Review and Meta-analysis of Prospective Studies

Adverse childhood experiences (ACEs) are strongly associated with impaired cognitive control, yet research on ACEs' effects across cognitive control domains-working memory, cognitive flexibility, and inhibitory control-remains sparse. This systematic review and meta-analysis evaluated the overall impact of ACEs on each of these cognitive control domains and explored moderating factors such as age, gender, cognitive control paradigms, and ACEs subtypes based on the dimensional model of adversity and psychopathology. A database search was conducted in SCOPUS, MedLine, PsycINFO, and Web of Science. Only prospective studies were included to ensure temporal order inferences, with at least two data collection points, assessing ACEs at baseline (T1) and cognitive control during follow-up (T2). Thirty-two studies (N = 26,863) producing 124 effect sizes were analyzed. Three-level meta-analyses revealed small-to-medium negative associations between ACEs and overall cognitive control (g = -0.32), and in each domain: working memory (g = -0.28), cognitive flexibility (g = -0.28), and inhibitory control (g = -0.32). The negative associations between ACEs and cognitive control were consistent across age, gender, and cognitive control paradigms. ACEs subtypes moderated the association with cognitive flexibility (p = .04) but not working memory or inhibitory control. Specifically, the deprivation subtype exhibited a stronger negative association with cognitive flexibility compared to threat and threat-and-deprivation subtypes. These findings highlight the pervasive negative impact of ACEs on cognitive control across ages and emphasize the need for targeted interventions. Implications, current gaps, limitations in research, and future study recommendations are discussed.

Thyroid hormone remodels cortex to coordinate body-wide metabolism and exploration

Animals adapt to environmental conditions by modifying the function of their internal organs, including the brain. To be adaptive, alterations in behavior must be coordinated with the functional state of organs throughout the body. Here, we find that thyroid hormone-a regulator of metabolism in many peripheral organs-directly activates cell-type-specific transcriptional programs in the frontal cortex of adult male mice. These programs are enriched for axon-guidance genes in glutamatergic projection neurons, synaptic regulatory genes in both astrocytes and neurons, and pro-myelination factors in oligodendrocytes, suggesting widespread plasticity of cortical circuits. Indeed, whole-cell electrophysiology revealed that thyroid hormone alters excitatory and inhibitory synaptic transmission, an effect that requires thyroid hormone-induced gene regulatory programs in presynaptic neurons. Furthermore, thyroid hormone action in the frontal cortex regulates innate exploratory behaviors and causally promotes exploratory decision-making. Thus, thyroid hormone acts directly on the cerebral cortex in males to coordinate exploratory behaviors with whole-body metabolic state.

Fentanyl self-administration is accelerated by methamphetamine co-use and results in worsened hypodopaminergia in male, but not female rats

Combined use of fentanyl and methamphetamine (FENT + METH) has increased in recent years and has been documented in a growing number overdose deaths each year. The impact of FENT + METH on behavior and neurobiology is not well understood. In this study, male and female Long Evans rats were tested on a limited access, fixed ratio 1 self-administration schedule for increasing doses (1.25-5 μg/kg/infusion; iv) of fentanyl, with and without a single dose (0.1 mg/kg/infusion; iv) of methamphetamine, for 15 days. FENT + METH abolished dose responsiveness to fentanyl in all rats and accelerated intake in males, resulting in patterns of responding that may be more likely to result in adverse effects. Ex vivo slice voltammetry in the nucleus accumbens core showed decreases in dopamine release and reuptake (Vmax) following FENT + METH exposure, compared with saline, fentanyl, and methamphetamine alone groups at baseline parameters. Further, significant decreases in dopamine release were observed across a range of stimulation intensities following FENT + METH exposure. Overall, male and female rats displayed sex-specific behavioral and neurobiological responses to FENT + METH exposure, with males displaying increased vulnerability.

Sex-specific psychological risk profiles of CVD in the HUNT study: the role of neuroticism and extraversion

OBJECTIVE

The aim was to investigate psychological risk profiles of cardiovascular disease (CVD). Depression and anxiety have been linked to CVD, but research has not incorporated personality and sex-specific analyses are warranted. In this study, we examine the role of sex, neuroticism, extraversion, anxiety and depression on the risk of CVD.

METHOD

Using data from the HUNT-study and the mortality register, 32,383 (57.10% men) participants were followed for an average of 10.48 years. During this time, 142 died of myocardial infarction (MI) and 111 of stroke.

RESULTS

Cox regression showed that depression (HR = 1.07, 95% CI = [1.00, 1.14]) and neuroticism (1.23 [1.08, 1.40]) were significantly related to an increased risk of MI. One standard unit increase in depression and neuroticism was associated with 1.22 [CI 1.01, 1.47] increase and 1.43 [CI 1.14, 0.78] increase in the risk of MI respectively. For stroke, there was no significant effect of anxiety, depression or personality. However, we found a significant interaction effect between sex and extraversion where higher extraversion was associated with greater risk of stroke for women only.

CONCLUSIONS

Both neuroticism and depression were related to MI. We observed an interaction between extraversion and sex with stroke, but the effect size was small. The role of extroversion as a risk factor for CVD remains inconclusive.

Early Life Trauma, Emotion Dysregulation and Hormonal Sensitivity Across Female Reproductive Life Events

PURPOSE OF REVIEW

To explore the relationship between early life trauma, hormonal sensitivity, and psychiatric disorders across female-reproductive life events, with a focus on the neurobiological mechanisms.

RECENT FINDINGS

Childhood trauma significantly increases the risk of subsequent mood disorders during periods of intense hormonal fluctuation such as premenstrual, pregnancy, postpartum, and perimenopause. Neurobiological changes resulting from early trauma influence emotion regulation, which emerges as a key predisposing, exacerbating, and perpetuating factor to hormonal sensitivity and subsequent psychiatric symptoms. We identified altered stress response and allopregnanolone imbalance, bias in cognitive processing of emotions, neuroimage correlates and sleep disturbances as potential underlying neurobiological mechanisms. This review integrates cumulative findings supporting a theoretical framework linking early life trauma to hormonal sensitivity and mood disorders. We propose that some women might be more susceptible to such hormonal fluctuations because of emotion dysregulation following significant early life trauma.

Therapeutic Effects Of Combined and Chronic Treatment of Tat-GluA23y and D-Serine on Cognitive Dysfunction in Postmenopausal Rats

BACKGROUND

The incidence of Alzheimer's disease (AD) in female gender compared with male has been addressed as a health concern, particularly in menopausal age. We here hypothesized that co-administration of NMDARs agonist (D-serine) and AMPARs endocytosis inhibitor (Tat-GluA23y) might be a potential target for alleviating memory impairment in sporadic Alzheimer model of rats.

METHODS

Forty-eight female Wistar rats weighing 200-220 randomly divided into six groups. One month later, ovariectomized rats underwent stereotaxic surgery and were cannulated into the brain lateral ventricles. Streptozotocin was injected (3 mg/kg), then animals received the related treatments until the day 51, which experienced acquisition of spatial memory in Morris Water Maze test. Finally, the level of phosphorylated cAMP response element binding protein (CREB) in the hippocampus was measured by Western blotting.

RESULTS

Co-administration of D-serine and GluA23y significantly enhanced the acquisition and retrieval of impaired spatial memory in ovariectomized rats with AD (p < .001). Compared to Glu-A 23, D-serine caused more improvement in the mentioned parameters above, however, these values for both groups were still significantly different from the control group (P < .05).

CONCLUSION

Simultaneous treatment with D-serine and GluA23y synergistically improved STZ induced spatial memory impairment in OVX rat, probably partly via increase in phosphorylated CREB protein.

Exploring sex differences in periodic leg movements during sleep across the lifespan of patients with restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) and periodic leg movements during sleep (PLMS) are prevalent sleep disorders with significant implications for health and well-being. While previous research has highlighted sex-related disparities in RLS and PLMS prevalence, comprehensive understanding of these differences across the lifespan remains limited. This study aims to explore sex differences in RLS and PLMS across diverse age groups, spanning ages 2 to over 80 years, and to investigate the underlying mechanisms influenced by sex hormones.

METHODS

A retrospective analysis was conducted on drug-free patients diagnosed with RLS, including 95 females (age range: 2-83.2 years) and 89 males (age range: 2-79.5 years). Polysomnographic recordings were analyzed to assess leg movement activity, including PLMS index and Periodicity index.

RESULTS

A more rapid increase in PLMS index was observed in women starting before age 10, plateauing lower than men until around age 55. An increase in women occurred after 55, lasting over a decade, while in men, PLMS index continued to rise after 75. Conversely, Periodicity index displayed a simpler pattern, increasing progressively from prepuberty to around 35 in males and 45-50 in females. Females maintained a slightly higher Periodicity index than males for over a decade after this age.

CONCLUSION

These findings underscore the complex interplay between sex hormones, age, and sleep disorders, highlighting the need for tailored approaches to diagnosis and management across diverse demographic cohorts. Further research is warranted to elucidate the underlying mechanisms and develop targeted interventions to optimize sleep health outcomes.

Real-World Effectiveness of Menopausal Hormone Therapy in Preventing Relapse in Women With Schizophrenia or Schizoaffective Disorder

OBJECTIVE

Antipsychotic effectiveness in preventing relapse declines around menopausal age in women with schizophrenia or schizoaffective disorder (SSD). It is not known whether systemic menopausal hormone therapy (MHT) can help to prevent psychosis relapse.

METHODS

A within-subject study design was used to study the effectiveness of MHT in preventing relapse in a Finnish nationwide cohort of women with SSD between 40 and 62 years of age who used MHT during follow-up (1994-2017). Hazard ratios adjusted for age and psychotropic drug use were calculated for psychosis relapse as main outcome and any psychiatric hospitalization as secondary outcome.

RESULTS

The study population comprised 3,488 women using MHT. Use of MHT was associated with a 16% lower relapse risk (adjusted hazard ratio [aHR]=0.84, 95% CI=0.78-0.90) when compared to non-use. Stratified by age, MHT was associated with decreased relapse risks when used between ages 40-49 (aHR=0.86, 95% CI=0.78-0.95) and ages 50-55 (aHR=0.74, 95% CI=0.66-0.83), but not between ages 56-62 (aHR=1.11, 95% CI=0.91-1.37). Similar effectiveness was found for estrogen alone or combined with fixed or sequential progestogens (aHRs between 0.79 and 0.86), transdermal and oral formulations (aHRs 0.75-0.87), and for most specific formulations (aHRs 0.75-0.85), except tibolone (aHR=1.04, 95% CI=0.75-1.44) and formulations with dydrogesterone (aHR=1.05, 95% CI=0.85-1.30). Similar results were observed with any psychiatric hospitalization as outcome measure.

CONCLUSIONS

The findings underscore the potential value of MHT in preventing psychosis relapse among women with SSD of menopausal age. These findings translate clinical evidence on the neuroprotective effects of estrogens to real-world settings, encompassing a group of women for whom current antipsychotic treatment options may be insufficient.

Investigating the influence of estrous cycle-dependent hormonal changes on neurogenesis in adult mice

OBJECTIVE

Neurogenesis is the process of generating new neurons from neural stem cells (NSCs) in the adult brain. Sex hormones play an essential role in the development of the brain. The aim of this study was to evaluate the neurogenic changes in the brain at different phases of the estrous cycle in adult mice.

MATERIALS AND METHODS

Female NMRI mice were divided into four groups: 1- Estrous, 2- Proestrous, 3- Metestrous, and 4- Diestrous. Different stages of the estrous cycle were determined by staining of vaginal smears. The level of estrogen, progesterone, prolactin, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) hormones was evaluated by the enzyme-linked immunosorbent assay (ELISA) method. The expression of brain-derived neurotrophic factor) BDNF), nerve growth factor (NGF), ciliary neurotrophic factor(CNTF)) genes in hippocampal and the expression of glial fibrillary acidic protein (GFAP) in subventricular zone (SVZ) tissue were evaluated.

RESULTS

The serum estrogen and FSH increased significantly in Proestrous group (p < 0.001). Also, progesterone and prolactin hormones were significantly increased in the Diaestrus group (p < 0.001). The expression levels of BDNF, NGF, and CNTF significantly increased in the hippocampal tissue of Proestrous and Diaestrus groups (p < 0.001). The number of GFAP+ cells in SVZ of the Proestrous and Diestrous groups had a significant increase (p < 0.05, p < 0.01, p < 0.001).

CONCLUSION

Our data showed that Changes in sex hormones, especially estrogen in the estrous cycle, can cause the production of new neurons and astrocytes in the hippocampus and SVZ. Therefore, the increase in neurotrophic factors in the Proestrus and Diestrus leads to neurogenesis in adult mice brains.

Effect of menstrual cycle on rewarding properties of alcohol cues in women

OBJECTIVE

Compared with men, women are disproportionately affected by alcohol, including greater risks of behavioral impairment and relapse from abstinence-based treatments. One potential mechanism underlying this disparity is ovarian hormone fluctuations across menstrual cycle phases, particularly estradiol (E2). Preclinical and clinical studies have shown that E2 levels positively correlate with alcohol consumption, suggesting E2 modulates drinking. Rewarding properties of alcohol are thought to mediate this relationship. The present study tested the degree to which women report increased rewarding effects from alcohol and heightened attention to alcohol-related cues when E2 was elevated during the late follicular phase of the menstrual cycle.

METHOD

Fifty women aged 21-29 participated in a within-subjects placebo-controlled study examining how menstrual cycle phase alters the rewarding properties of alcohol and alcohol-associated cues when sober and intoxicated, as measured by their attentional bias toward alcohol-associated cues and subjective reports. Measures were obtained following 0.60 g/kg alcohol and placebo during the early follicular phase when E2 was low and the late follicular phase (i.e., ovulation) when E2 was elevated.

RESULTS

Attentional bias to alcohol-associated cues was greater during the late follicular phase in both sober and intoxicated states. Women reported rewarding effects from alcohol, but no effects of phase were observed.

CONCLUSIONS

The findings suggest that the rewarding properties of alcohol-associated cues might be enhanced during the late follicular phase of the menstrual cycle when E2 is elevated, possibly increasing the risk for excessive drinking in women during this phase. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Ovariectomy and Estradiol Supplementation Prevents Cyclophosphamide- and Doxorubicin-Induced Spatial Memory Impairment in Tumor-Bearing MMTV-PyVT Mice

Chemotherapy-related cognitive impairments (CRCIs) encompass cognitive deficits in memory, attention, and executive function that arise during and following chemotherapy. CRCI symptoms are predominantly reported by female cancer patients but also occur in males. These impairments may involve reduced estradiol levels, which then increases vulnerability to the impact of tumors and chemotherapy on cognition. This study utilized the MMTV-PyVT mouse model of breast cancer to test the hypothesis that impaired ovarian function and associated estradiol levels play a critical role in CRCI susceptibility. Mice were either ovariectomized (OVX) or underwent sham surgery. The OVX group then received supplemental estradiol (E2) ad libitum in the drinking water to maintain physiological hormone levels. After tumor development, mice were trained in the Morris water maze to assess spatial memory, and subsequently, they received weekly injections of either saline or a combination of cyclophosphamide (CYP; 66.7 mg/kg, i.v.) and doxorubicin (DOX; 6.7 mg/kg, i.v.) for 4 weeks. Spatial memory was reassessed 10 d and then 35 d, after the final injections. Results demonstrated a significant disruption of normal ovarian cycling in sham-operated mice treated with CYP + DOX, as well as significant spatial memory impairments when compared with OVX mice supplemented with E2 This study suggests that chemotherapy-induced ovarian damage and the consequent drop in circulating estrogens significantly contribute to vulnerability to CRCIs, underscoring the importance of estradiol in mitigating CRCI risks.

Estradiol modulates changes in effective connectivity in emotion regulation networks

Hormonal changes in ovarian hormones like estradiol (E2) during the menstrual cycle affect emotional processes, including emotion recognition, memory, and regulation. So far, the neural underpinnings of the effect of E2 on emotional experience have been investigated using task-based functional magnetic resonance imaging (fMRI) and functional connectivity. In the present study, we examined whether the intrinsic network dynamics at rest (i.e., directed effective connectivity) related to emotion regulation are (1) modulated by E2 levels and (2) linked to behavioral emotion regulation ability. Hence, 29 naturally cycling women participated in two resting-state fMRI scans in their early follicular phase after being administered a placebo or an E2 valerate, respectively. Emotion regulation ability was assessed using a standard emotion regulation task in which participants were asked to down-regulate their emotions in response to negative images. The regions of two functionally predefined neural networks related to emotional down-regulation and reactivity were used to investigate effective connectivity at rest using spectral dynamic causal modelling. We found that E2, compared to placebo, resulted in changes in effective connectivity in both networks. In the regulation network, prefrontal regions showed distinct connectivity in the E2 compared to the placebo condition, while mixed results evolved in the emotional reactivity network. Stepwise regressions revealed that in the E2 condition a connection from the parietal to the prefrontal cortex predicted regulation ability. Our results demonstrate that E2 levels influence effective connectivity in networks underlying emotion regulation and emotional reactivity. Thus, E2 and its potential modification via hormonal administration may play a supporting role in the treatment of mental disorders that show a dysregulation of emotions.

[Prediction and timely identification of postpartum depression: results of the longitudinal RiPoD study in the context of the literature]

The first 4-6 weeks after childbirth are defined as the onset time for postpartum depression (PPD). Despite this known time frame there are significant gaps in the identification and treatment of PPD. The risk for postpartum depression (RiPoD) study investigated specific risk factors and predictors of postpartum psychological adjustment processes and the results are presented within the framework of a state of the art review of research. The dynamic neuroplastic changes in the maternal brain during pregnancy and the postpartum period appear to be closely linked to peripartum hormone fluctuations, which jointly influence the development of postpartum mood disorders. Hormonal risk factors such as baby blues and premenstrual syndrome have been found to have a bearing on PPD. The combination of these two factors predicts the risk of PPD with 83% sensitivity within the first week postpartum. Follow-up digital monitoring of symptom development in the first 6 weeks postpartum has enabled an accurate identification of women with PPD. Understanding the interaction between hormone fluctuations, neuroplasticity and psychiatric disorders should be an important target for future research. Early identification and diagnosis of PPD can be easily integrated into the clinical routine and everyday life.

Attentional bias to alcohol-related cues: effects of menstrual cycle phase and sex differences

RATIONALE

A recent study by our group found that women displayed greater attentional bias to alcohol-related cues during the late versus early follicular phase in both sober and intoxicated states, suggesting a greater risk of excessive drinking among women during this phase. Changes in attentional bias as a function of menstrual cycle phase raise questions about potential sex differences in the relative consistency by which women and men display attentional bias to alcohol over time.

OBJECTIVES

The present study tested sex differences in attentional bias to alcohol by comparing the change in women's attentional bias from early to late follicular phase to that observed in men over the same period.

METHODS

Twenty-five men and 25 women aged 21-32 participated in a placebo-controlled study examining sex differences in the rewarding properties of alcohol. Participants completed measures of attentional bias to alcohol-related cues during two sessions following both 0.6 g/kg alcohol and placebo. Test sessions occurred one week apart, and for female participants coincided with the early and late follicular phases.

RESULTS

Men consistently displayed attentional bias to alcohol-related cues across sessions under both doses. By contrast, women showed attentional bias only during the late follicular phase, at a magnitude greater than that observed in men, and persistent under both doses.

CONCLUSIONS

These findings highlight the potential role of sex and menstrual cycle phase in sensitizing drinkers to rewarding properties of alcohol-related cues. Men's motivation to drink may remain relatively consistent, whereas women may be most motivated during the late follicular phase.

Recurrent inhibition refines mental templates to optimize perceptual decisions

Translating sensory inputs to perceptual decisions relies on building internal representations of features critical for solving complex tasks. Yet, we still lack a mechanistic account of how the brain forms these mental templates of task-relevant features to optimize decision-making. Here, we provide evidence for recurrent inhibition: an experience-dependent plasticity mechanism that refines mental templates by enhancing γ-aminobutyric acid (GABA)-mediated (GABAergic) inhibition and recurrent processing in superficial visual cortex layers. We combine ultrahigh-field (7 T) functional magnetic resonance imaging at submillimeter resolution with magnetic resonance spectroscopy to investigate the fine-scale functional and neurochemical plasticity mechanisms for optimized perceptual decisions. We demonstrate that GABAergic inhibition increases following training on a visual (i.e., fine orientation) discrimination task, enhancing the discriminability of orientation representations in superficial visual cortex layers that are known to support recurrent processing. Modeling functional and neurochemical plasticity interactions reveals that recurrent inhibitory processing optimizes brain computations for perpetual decisions and adaptive behavior.

Menstrual cycle-driven hormone concentrations co-fluctuate with white and gray matter architecture changes across the whole brain

Cyclic fluctuations in hypothalamic-pituitary-gonadal axis (HPG-axis) hormones exert powerful behavioral, structural, and functional effects through actions on the mammalian central nervous system. Yet, very little is known about how these fluctuations alter the structural nodes and information highways of the human brain. In a study of 30 naturally cycling women, we employed multidimensional diffusion and T1-weighted imaging during three estimated menstrual cycle phases (menses, ovulation, and mid-luteal) to investigate whether HPG-axis hormone concentrations co-fluctuate with alterations in white matter (WM) microstructure, cortical thickness (CT), and brain volume. Across the whole brain, 17β-estradiol and luteinizing hormone (LH) concentrations were directly proportional to diffusion anisotropy (μFA; 17β-estradiol: β1 = 0.145, highest density interval (HDI) = [0.211, 0.4]; LH: β1 = 0.111, HDI = [0.157, 0.364]), while follicle-stimulating hormone (FSH) was directly proportional to CT (β1 = 0 .162, HDI = [0.115, 0.678]). Within several individual regions, FSH and progesterone demonstrated opposing relationships with mean diffusivity (Diso) and CT. These regions mainly reside within the temporal and occipital lobes, with functional implications for the limbic and visual systems. Finally, progesterone was associated with increased tissue (β1 = 0.66, HDI = [0.607, 15.845]) and decreased cerebrospinal fluid (CSF; β1 = -0.749, HDI = [-11.604, -0.903]) volumes, with total brain volume remaining unchanged. These results are the first to report simultaneous brain-wide changes in human WM microstructure and CT coinciding with menstrual cycle-driven hormone rhythms. Effects were observed in both classically known HPG-axis receptor-dense regions (medial temporal lobe, prefrontal cortex) and in other regions located across frontal, occipital, temporal, and parietal lobes. Our results suggest that HPG-axis hormone fluctuations may have significant structural impacts across the entire brain.

The interplay of oxytocin and sex hormones

The neuropeptide oxytocin has historically been associated with reproduction and maternal behavior. However, more recent research has uncovered that oxytocin has a much wider range of roles in physiology and behavior. Despite the excitement surrounding potential therapeutical applications of intranasally administered oxytocin, the results of these intervention studies have been inconsistent. Various reasons for these mixed results have been proposed, which tend to focus on methodological issues, such as study design. While methodological issues are certainly important, emerging evidence suggests that the interaction between oxytocin and sex hormones may also account for these varied findings. To better understand the purpose and function of the interaction of oxytocin with sex hormones, with a focus on estrogens, progesterone, and testosterone, we conducted a comprehensive thematic review via four perspectives: evolutionary, developmental, mechanistic, and survival. Altogether, this synergistic approach highlights the critical function of sex hormone activity for accomplishing the diverse roles of oxytocin via the modulation of oxytocin release and oxytocin receptor activity, which is also likely to contribute to the heterogeneity of outcomes after oxytocin administration.

Menopause depression: Under recognised and poorly treated

Menopause is a biological process experienced by all people assigned female at birth. A significant number of women experience mental ill health related to the major brain gonadal hormone shifts that occur in their midlife. There is poor understanding and management of the complex mental ill health issues, with the biological brain hormone changes receiving little formal attention. The current treatment advice is to manage this special type of mental ill health in the same way that all mental ill health is managed. This leads to poor outcomes for women and their families. Many women leave the workforce earlier than expected due to menopause-related depression and anxiety, with subsequent loss of salary and superannuation. Others describe being unable to adequately parent or maintain meaningful relationships - all ending in a poor quality of life. We are a large and diverse group of national and international clinicians, lived experience and social community advocates, all working together to innovate the current approaches available for women with menopausal mental ill health. Above all, true innovation is only possible when the woman with lived experience of menopause is front and centre of this debate.

Comparison of autogenous and reactive type obsessive-compulsive disorders in terms of clinical characteristics: A meta-analysis study

Obsessive-compulsive disorder (OCD) has been divided into two subgroups autogenous and reactive types, based on obsessive symptoms. To our knowledge, no meta-analysis study compares sociodemographic and clinical characteristics. Investigation of the differences between the two groups in terms of these basic characteristics may provide information about the accuracy of this classification. This is the first meta-analysis to examine gender, age at onset and some clinical differences between patients with autogenous and reactive OCD. Electronic bibliographic databases of Scopus and PubMed were searched up to March 2024. Random effect models were conducted for this meta-analysis. The analysis was carried out using the standardized mean difference as the outcome measure. Publication bias was evaluated using the Begg and Eggers funnel plot, and fail-safe N calculation using the Rosenthal approach. The current meta-analysis summarizes the data from primary studies comparing the gender rates, age at onset of OCD, severity of obsessive-compulsive symptoms, and severity of depression and anxiety symptoms between autogenous and reactive types of OCD. The results of this study showed that the rate of male gender was higher in the autogenous type OCD. In addition, increased severity of anxiety, and depression were associated with autogenous type OCD. There was no significant difference between groups regarding the severity of obsessive-compulsive symptoms. Age of OCD onset findings were insignificant, but excluding an outlier study suggested earlier onset in autogenous type OCD. These results support the distinction between autogenous and reactive type OCD.

Sex Differences in Alcohol Use: Is It All About Hormones?

Risky alcohol use and alcohol use disorders (AUD) are a rising problem in women, yet a major disparity in our understanding of what drives alcohol consumption in women remains. Historically biomedical research has focused on male subjects; however, recent increases in reporting of females, have highlighted major differences between the sexes. Here we review the current literature of the effect of gonadal steroid hormones (estrogens, androgens, and progestins), neurosteriods, and neurobiological factors on alcohol use in clinical and preclinical studies of both sexes. Further, we briefly discuss how fundamental sex differences in genetics, metabolism, neuroimmune, and stress responses may influence sex differences in alcohol intake. Comparing the sexes could aid in the discovery of novel therapeutics to treat AUD, and implementation of current treatment options in women.

Physical reserve and its underpinning functional neural networks moderate the relationship between white matter hyperintensity and postural balance in older adults with subcortical ischemic vascular cognitive impairment

White matter hyperintensities (WMH) are markers of subcortical ischemic vascular cognitive impairment (SIVCI) associated with impaired postural balance. Physical reserve (PR) is a recently established construct that reflects one's capacity to maintain physical function despite brain pathology. This cross-sectional study aims to map functional networks associated with PR, and examining the relationship between PR, WMH, and postural balance. PR was defined in 22 community-dwelling older adults with SIVCI. Functional networks of PR were computed using general linear model. Subsequent analyses examined whether PR and relevant networks moderated the relationship between WMH and postural balance under two conditions-eyes open while standing on foam (EOF) or on floor (EONF). We found that PR and the relevant networks-frontoparietal network (FPN) and default mode network (DMN)-significantly moderated the association between WMH and postural balance. For individuals with high PR, postural balance remained stable regardless of the extent of WMH load; whereas for those with low PR, postural balance worsened as WMH load increased. These results suggest the attenuated effects of WMH on postural stability due to PR may be underpinned by functional neural network reorganization in the FPN and DMN as a part of compensatory processes.

Associations of endogenous estrogens, plasma Alzheimer's disease biomarkers, and APOE4 carrier status on regional brain volumes in postmenopausal women

Background

Women carrying the APOE4 allele are at greater risk of developing Alzheimer's disease (AD) from ages 65-75 years compared to men. To better understand the elevated risk conferred by APOE4 carrier status among midlife women, we investigated the separate and interactive associations of endogenous estrogens, plasma AD biomarkers, and APOE4 carrier status on regional brain volumes in a sample of late midlife postmenopausal women.

Methods

Participants were enrolled in MsBrain, a cohort study of postmenopausal women (n = 171, mean age = 59.4 years, mean MoCA score = 26.9; race = 83.2% white, APOE4 carriers = 40). Serum estrone (E1) and estradiol (E2) levels were assessed using liquid chromatography-tandem mass spectrometry. APOE genotype was determined using TaqMan SNP genotyping assays. Plasma AD biomarkers were measured using single molecule array technology. Cortical volume was measured and segmented by FreeSurfer software using individual T1w MPRAGE images. Multiple linear regression models were conducted to determine whether separate and interactive associations between endogenous estrogen levels, plasma AD biomarkers (Aβ42/Aβ40, Aβ42/p-tau181), and APOE4 carrier status predict regional brain volume (21 regions per hemisphere, selected a priori); and, whether significant interactive associations between estrogens and AD biomarkers on brain volume differed by APOE4 carrier status.

Results

There was no main effect of APOE4 carrier status on regional brain volumes, endogenous estrogen levels, or plasma AD biomarkers. Estrogens did not associate with regional brain volumes, except for positive associations with left caudal middle frontal gyrus and fusiform volumes. The interactive association of estrogens and APOE4 carrier status on brain volume was not significant for any region. The interactive association of estrogens and plasma AD biomarkers predicted brain volume of several regions. Higher E1 and E2 were more strongly associated with greater regional brain volumes among women with a poorer AD biomarker profile (lower Aβ42/40, lower Aβ42/p-tau181 ratios). In APOE4-stratified analyses, these interactions were driven by non-APOE4 carriers.

Conclusion

We demonstrate that the brain volumes of postmenopausal women with poorer AD biomarker profiles benefit most from higher endogenous estrogen levels. These findings are driven by non-APOE4 carriers, suggesting that APOE4 carriers may be insensitive to the favorable effects of estrogens on brain volume in the postmenopause.

Evaluating Sex Steroid Hormone Neuroprotection in Spinal Cord Injury in Animal Models: Is It Promising in the Clinic?

The primary mechanism of traumatic spinal cord injury (SCI) comprises the initial mechanical trauma due to the transmission of energy to the spinal cord, subsequent deformity, and persistent compression. The secondary mechanism of injury, which involves structures that remained undamaged after the initial trauma, triggers alterations in microvascular perfusion, the liberation of free radicals and neurotransmitters, lipid peroxidation, alteration in ionic concentrations, and the consequent cell death by necrosis and apoptosis. Research in the treatment of SCI has sought to develop early therapeutic interventions that mitigate the effects of these pathophysiological mechanisms. Clinical and experimental evidence has demonstrated the therapeutic benefits of sex-steroid hormone administration after traumatic brain injury and SCI. The administration of estradiol, progesterone, and testosterone has been associated with neuroprotective effects, better neurological recovery, and decreased mortality after SCI. This review evaluated evidence supporting hormone-related neuroprotection over SCI and the possible underlying mechanisms in animal models. As neuroprotection has been associated with signaling pathways, the effects of these hormones are observed on astrocytes and microglia, modulating the inflammatory response, cerebral blood flow, and metabolism, mediating glutamate excitotoxicity, and their antioxidant effects. Based on the current evidence, it is essential to analyze the benefit of sex steroid hormone therapy in the clinical management of patients with SCI.

Sex-Specific Mechanisms Underlie Long-Term Potentiation at Hippocampus→Medium Spiny Neuron Synapses in the Medial Shell of the Nucleus Accumbens

Sex differences have complicated our understanding of the neurobiological basis of many behaviors that are key for survival. As such, continued elucidation of the similarities and differences between sexes is necessary to gain insight into brain function and vulnerability. The connection between the hippocampus (Hipp) and nucleus accumbens (NAc) is a crucial site where modulation of neuronal activity mediates reward-related behavior. Our previous work demonstrated that long-term potentiation (LTP) of Hipp→NAc synapses is rewarding, and mice can establish learned associations between LTP of these synapses and the contextual environment in which LTP occurred. Here, we investigated sex differences in the mechanisms underlying Hipp→NAc LTP using whole-cell electrophysiology and pharmacology. We observed similarities in basal synaptic strength between males and females and found that LTP occurs postsynaptically with similar magnitudes in both sexes. However, key sex differences emerged as LTP in males required NMDA receptors (NMDAR), whereas LTP in females utilized an NMDAR-independent mechanism involving L-type voltage-gated Ca2+ channels (VGCCs) and estrogen receptor α (ERα). We also uncovered sex-similar features as LTP in both sexes depended on CaMKII activity and occurred independently of dopamine-1 receptor (D1R) activation. Our results have elucidated sex-specific molecular mechanisms for LTP in an integral pathway that mediates reward-related behaviors, emphasizing the importance of considering sex as a variable in mechanistic studies. Continued characterization of sex-specific mechanisms underlying plasticity will offer novel insight into the neurophysiological basis of behavior, with significant implications for understanding how diverse processes mediate behavior and contribute to vulnerability to developing psychiatric disorders.

The cortisol awakening response is blunted in healthy women early postpartum

INTRODUCTION

The dynamic capacity of the hypothalamic-pituitary-adrenal (HPA) axis supports healthy adaptions to stress and play a key role in maintaining mental health. Perinatal adaptations in the HPA-axis dynamics in terms of the Cortisol Awakening Response (CAR), may be involved in dysregulation of perinatal mental health. We aimed to determine if CAR and absolute evening cortisol early postpartum differed from non-perinatal women and evaluate the association between the CAR and maternal mental well-being.

METHODS

The CAR was computed as the area under the curve with respect to increase from baseline from serial home-sampling of saliva across 0-60 minutes from awakening. We evaluated differences in CAR and absolute evening cortisol between postpartum women (N=50, mean postpartum days: 38, SD: ±11) and non-perinatal women (N=91) in a multiple linear regression model. We also evaluated the association between CAR and maternal mental well-being in a multiple linear regression model.

RESULTS

We found that healthy postpartum women had a blunted CAR (p<0.001) corresponding to 84% reduction and 80% lower absolute evening cortisol (p<0.001) relative to non-perinatal healthy women. In the postpartum group, there was a trend-level association between lower CAR and higher scores on the WHO Well-Being Index (WHO-5) (p=0.048) and lower Edinburgh Postnatal Depression Scale (EPDS) scores (p=0.04).

CONCLUSION

Our data emphasize the unique hormonal landscape during the postpartum period in terms of blunted CAR and lower absolute evening cortisol in healthy women early postpartum compared to non-perinatal. Our findings show a potential association between a reduced CAR and improved mental well-being during early motherhood, which suggests that reduced CAR might reflect healthy adjustment to early motherhood.

Emotion recognition and regulation in males: Role of sex and stress steroids

Understanding emotions in males is crucial given their higher susceptibility to substance use, interpersonal violence, and suicide compared to females. Steroid hormones are assumed to be critical biological factors that affect and modulate emotion-related behaviors, together with psychological and social factors. This review explores whether males' abilities to recognize emotions of others and regulate their own emotions are associated with testosterone, cortisol, and their interaction. Higher levels of testosterone were associated with improved recognition and heightened sensitivity to threatening faces. In contrast, higher cortisol levels positively impacted emotion regulation ability. Indirect evidence from neuroimaging research suggested a link between higher testosterone levels and difficulties in cognitive emotion regulation. However, this notion must be investigated in future studies using different emotion regulation strategies and considering social status. The present review contributes to the understanding of how testosterone and cortisol affect psychological well-being and emotional behavior in males.

Parental status and markers of brain and cellular age: A 3D convolutional network and classification study

Recent research shows prominent effects of pregnancy and the parenthood transition on structural brain characteristics in humans. Here, we present a comprehensive study of how parental status and number of children born/fathered links to markers of brain and cellular ageing in 36,323 UK Biobank participants (age range 44.57-82.06 years; 52% female). To assess global effects of parenting on the brain, we trained a 3D convolutional neural network on T1-weighted magnetic resonance images, and estimated brain age in a held-out test set. To investigate regional specificity, we extracted cortical and subcortical volumes using FreeSurfer, and ran hierarchical clustering to group regional volumes based on covariance. Leukocyte telomere length (LTL) derived from DNA was used as a marker of cellular ageing. We employed linear regression models to assess relationships between number of children, brain age, regional brain volumes, and LTL, and included interaction terms to probe sex differences in associations. Lastly, we used the brain measures and LTL as features in binary classification models, to determine if markers of brain and cellular ageing could predict parental status. The results showed associations between a greater number of children born/fathered and younger brain age in both females and males, with stronger effects observed in females. Volume-based analyses showed maternal effects in striatal and limbic regions, which were not evident in fathers. We found no evidence for associations between number of children and LTL. Classification of parental status showed an Area under the ROC Curve (AUC) of 0.57 for the brain age model, while the models using regional brain volumes and LTL as predictors showed AUCs of 0.52. Our findings align with previous population-based studies of middle- and older-aged parents, revealing subtle but significant associations between parental experience and neuroimaging-based surrogate markers of brain health. The findings further corroborate results from longitudinal cohort studies following parents across pregnancy and postpartum, potentially indicating that the parenthood transition is associated with long-term influences on brain health.

In vivo brain estrogen receptor density by neuroendocrine aging and relationships with cognition and symptomatology

17β-estradiol, the most biologically active estrogen, exerts wide-ranging effects in brain through its action on estrogen receptors (ERs), influencing higher-order cognitive function and neurobiological aging. However, our knowledge of ER expression and regulation by neuroendocrine aging in the living human brain is limited. This in vivo brain 18F-fluoroestradiol (18F-FES) Positron Emission Tomography (PET) study of healthy midlife women reveals progressively higher ER density over the menopause transition in estrogen-regulated networks. Effects were independent of age, plasma estradiol and sex hormone binding globulin, and were highly consistent, correctly classifying all women as being postmenopausal or premenopausal. Higher ER density in target regions was associated with poorer memory performance for both postmenopausal and perimenopausal groups, and predicted presence of self-reported mood and cognitive symptoms after menopause. These findings provide novel insights on brain ER density modulation by female neuroendocrine aging, with clinical implications for women's health.

Individual differences in the boldness of female zebrafish are associated with alterations in serotonin function

One of the most prevalent axes of behavioral variation in both humans and animals is risk taking, where individuals that are more willing to take risk are characterized as bold while those that are more reserved are regarded as shy. Brain monoamines (i.e. serotonin, dopamine and noradrenaline) have been found to play a role in a variety of behaviors related to risk taking. Using zebrafish, we investigated whether there was a relationship between monoamine function and boldness behavior during exploration of a novel tank. We found a correlation between serotonin metabolism (5-HIAA:5-HT ratio) and boldness during the initial exposure to the tank in female animals. The DOPAC:DA ratio correlated with boldness behavior on the third day in male fish. There was no relationship between boldness and noradrenaline. To probe differences in serotonergic function in bold and shy fish, we administered a selective serotonin reuptake inhibitor, escitalopram, and assessed exploratory behavior. We found that escitalopram had opposing effects on thigmotaxis in bold and shy female animals: the drug caused bold fish to spend more time near the center of the tank and shy fish spent more time near the periphery. Taken together, our findings indicate that variation in serotonergic function has sex-specific contributions to individual differences in risk-taking behavior.

Sexual Dimorphism, Altered Hippocampal Glutamatergic Neurotransmission and Cognitive Impairment in APP Knock-In Mice

Background

It is well established that glutamatergic neurotransmission plays an essential role in learning and memory. Previous studies indicate that glutamate dynamics shift with Alzheimer's disease (AD) progression, contributing to negative cognitive outcomes.

Objective

In this study, we characterized hippocampal glutamatergic signaling with age and disease progression in a knock-in mouse model of AD (APPNL-F/NL-F).

Methods

At 2-4 and 18+ months old, male and female APPNL/NL, APPNL-F/NL-F, and C57BL/6 mice underwent cognitive assessment using Morris water maze (MWM) and Novel Object Recognition (NOR). Then, basal and 70 mM KCl stimulus-evoked glutamate release was measured in the dentate gyrus (DG), CA3, and CA1 regions of the hippocampus using a glutamate-selective microelectrode in anesthetized mice.

Results

Glutamate recordings support elevated stimulus-evoked glutamate release in the DG and CA3 of young APPNL-F/NL-F male mice that declined with age compared to age-matched control mice. Young female APPNL-F/NL-F mice exhibited increased glutamate clearance in the CA1 that slowed with age compared to age-matched control mice. Male and female APPNL-F/NL-F mice exhibited decreased CA1 basal glutamate levels, while males also showed depletion in the CA3. Cognitive assessment demonstrated impaired spatial cognition in aged male and female APPNL-F/NL-F mice, but only aged females displayed recognition memory deficits compared to age-matched control mice. Conclusions: These findings confirm a sex-dependent hyper-to-hypoactivation glutamatergic paradigm in APPNL-F/NL-F mice. Further, data illustrate a sexually dimorphic biological aging process resulting in a more severe cognitive phenotype for female APPNL-F/NL-F mice than their male counterparts. Research outcomes mirror that of human AD pathology and provide further evidence of divergent AD pathogenesis between sexes.

Early-onset vasomotor symptoms and development of depressive symptoms among premenopausal women

BACKGROUND

We investigated the association between vasomotor symptoms (VMSs) and the onset of depressive symptoms among premenopausal women.

METHODS

This cross-sectional study included 4376 premenopausal women aged 42-52 years, and the cohort study included 2832 women without clinically relevant depressive symptoms at baseline. VMSs included the symptoms of hot flashes and night sweats. Depressive symptoms were evaluated using the Center for Epidemiological Studies Depression Scale; a score of ≥16 was considered to define clinically relevant depressive symptoms.

RESULTS

Premenopausal Women with VMSs at baseline exhibited a higher prevalence of depressive symptoms compared with women without VMSs at baseline (multivariable-adjusted prevalence ratio 1.76, 95 % confidence interval [CI] 1.47-2.11). Among the 2832 women followed up (median, 6.1 years), 406 developed clinically relevant depressive symptoms. Women with versus without VMSs had a significantly higher risk of developing clinically relevant depressive symptoms (multivariable-adjusted hazard ratio, 1.72; 95 % CI 1.39-2.14). VMS severity exhibited a dose-response relationship with depressive symptoms (P for trend <0.05).

LIMITATIONS

Self-reported questionnaires were only used to obtain VMSs and depressive symptoms, which could have led to misclassification. We also could not directly measure sex hormone levels.

CONCLUSIONS

Even in the premenopausal stage, women who experience hot flashes or night sweats have an increased risk of present and developed clinically relevant depressive symptoms. It is important to conduct mental health screenings and provide appropriate support to middle-aged women who experience early-onset VMSs.

Test-retest reliability and time-of-day variations of perfusion imaging at rest and during a vigilance task

Arterial spin-labeled perfusion and blood oxygenation level-dependent functional MRI are indispensable tools for noninvasive human brain imaging in clinical and cognitive neuroscience, yet concerns persist regarding the reliability and reproducibility of functional MRI findings. The circadian rhythm is known to play a significant role in physiological and psychological responses, leading to variability in brain function at different times of the day. Despite this, test-retest reliability of brain function across different times of the day remains poorly understood. This study examined the test-retest reliability of six repeated cerebral blood flow measurements using arterial spin-labeled perfusion imaging both at resting-state and during the psychomotor vigilance test, as well as task-induced cerebral blood flow changes in a cohort of 38 healthy participants over a full day. The results demonstrated excellent test-retest reliability for absolute cerebral blood flow measurements at rest and during the psychomotor vigilance test throughout the day. However, task-induced cerebral blood flow changes exhibited poor reliability across various brain regions and networks. Furthermore, reliability declined over longer time intervals within the day, particularly during nighttime scans compared to daytime scans. These findings highlight the superior reliability of absolute cerebral blood flow compared to task-induced cerebral blood flow changes and emphasize the importance of controlling time-of-day effects to enhance the reliability and reproducibility of future brain imaging studies.