Estrogen actions in the nervous system

Investigating the shared genetic architecture between schizophrenia and sex hormone traits

Sex hormones are involved in schizophrenia pathogenesis; however, their direction and genetic overlap remain unknown. By leveraging summary statistics from large-scale genome-wide association studies, we quantified the shared genetic architecture between schizophrenia and four sex hormone traits. Linkage disequilibrium score regression and bivariate causal mixture modeling strategies showed significant positive correlations between sex hormone-binding globulin (SHBG), total testosterone, and schizophrenia, while bioavailable testosterone and schizophrenia were negatively correlated. Estradiol showed a weak positive correlation with schizophrenia, with little polygenic overlap. The conjunctional false discovery rate method identified 303 lead single-nucleotide polymorphisms (SNPs) in jointly shared genomic loci between schizophrenia and SHBG, with 130, 52, and 9 SNPs shared between schizophrenia and total testosterone, bioavailable testosterone, and estradiol, respectively. Functional annotation suggests that mitotic sister chromatid segregation and N-glycan biosynthesis may be involved in common mechanisms underlying sex hormone regulation and schizophrenia onset. In conclusion, this study clarified the inherent relationships between schizophrenia and sex hormone traits, highlighted the roles of mitotic sister chromatid segregation and N-glycan biosynthesis in the pathogenesis of schizophrenia, and delivered potential targets for further validation.

Dynamic change of estrogen and progesterone metabolites in human urine during pregnancy

Endogenous estrogen and progesterone and their metabolites play a key role in regulating and maintaining the normal pregnancy process. However, the dynamic change of these estrogen and progesterone metabolites' level across the entire gestational period is not fully revealed. This study systematically measures the temporal changes of estrogen, progesterone, and their metabolites in human urine during normal pregnancy using ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). We find that the levels of estrone, estradiol, estriol, 16-epiestriol, 17-epiestriol, 2-methoxyestradiol, and 4-hydroxyestrone gradually increase during pregnancy. The levels of 2-hydroxyestrone, 2-hydroxyestradiol, and 4-hydroxyestradiol rapidly decrease in the early pregnancy and then maintain at lower levels. The levels of 4-methoxyestradiol, 4-methoxyestrone and 2-methoxyestrone peak in the mid-pregnancy and then gradually decrease. The levels of pregnenolone, 17α-hydroxy pregnenolone, 17α-hydroxy progesterone, pregnanolone, epipregnanolone gradually increase during pregnancy. The levels of progesterone, 20α-hydroxy progesterone, 5α-dihydroprogesterone and 5β-dihydroprogesterone first increase in the mid pregnancy and then decrease in the late pregnancy. In sum, this study comprehensively depicts the dynamic change of estrogen, progesterone, and their metabolites in human urine during pregnancy, which lays the foundation for hormone monitoring and early diagnosis of pregnancy complications, and further mechanistic study of the roles of these metabolites in pregnancy.

Potential Regulation of the Long Non-Coding RNA Metastasis-Associated Lung Adenocarcinoma Transcript1 by Estrogen in Parkinson's Disease

Parkinson's disease (PD) is the second-leading cause of death among neurodegenerative disease after Alzheimer's disease (AD), affecting around 2% of the population. It is expected that the incidence of PD will exceed 12 million by 2040. Meanwhile, there is a recognized difference in the phenotypical expression of the disease and response to treatment between men and women. Men have twice the incidence of PD compared to women, who have a late onset and worse prognosis that is usually associated with menopause. In addition, the incidence of PD in women is associated with the cumulative estrogen levels in their bodies. These differences are suggested to be due to the protective effect of estrogen on the brain, which cannot be given in clinical practice to improve the symptoms of the disease because of its peripheral side effects, causing cancer in both males and females in addition to the feminizing effect it has on males. As PD pathophysiology involves alteration in the expression levels of multiple LncRNAs, including metastatic-associated lung adenocarcinoma transcript 1 (MALAT1), and as estrogen has been illustrated to control the expression of MALAT1 in multiple conditions, it is worth investigating the estrogen-MALAT1 interaction in Parkinson's disease to mimic its protective effect on the brain while avoiding its peripheral side effects. The following literature review suggests the potential regulation of MALAT1 by estrogen in PD, which would enhance our understanding of the pathophysiology of the disease, improving the development of more tailored and effective treatments.

Sexual and Metabolic Differences in Hippocampal Evolution: Alzheimer's Disease Implications

Sex differences in brain metabolism and their relationship to neurodegenerative diseases like Alzheimer's are an important emerging topic in neuroscience. Intrinsic anatomic and metabolic differences related to male and female physiology have been described, underscoring the importance of considering biological sex in studying brain metabolism and associated pathologies. The hippocampus is a key structure exhibiting sex differences in volume and connectivity. Adult neurogenesis in the dentate gyrus, dendritic spine density, and electrophysiological plasticity contribute to the hippocampus' remarkable plasticity. Glucose transporters GLUT3 and GLUT4 are expressed in human hippocampal neurons, with proper glucose metabolism being crucial for learning and memory. Sex hormones play a major role, with the aromatase enzyme that generates estradiol increasing in neurons and astrocytes as an endogenous neuroprotective mechanism. Inhibition of aromatase increases gliosis and neurodegeneration after brain injury. Genetic variants of aromatase may confer higher Alzheimer's risk. Estrogen replacement therapy in postmenopausal women prevents hippocampal hypometabolism and preserves memory. Insulin is also a key regulator of hippocampal glucose metabolism and cognitive processes. Dysregulation of the insulin-sensitive glucose transporter GLUT4 may explain the comorbidity between type II diabetes and Alzheimer's. GLUT4 colocalizes with the insulin-regulated aminopeptidase IRAP in neuronal vesicles, suggesting an activity-dependent glucose uptake mechanism. Sex differences in brain metabolism are an important factor in understanding neurodegenerative diseases, and future research must elucidate the underlying mechanisms and potential therapeutic implications of these differences.

Effectiveness of Tri-Kaysorn-Mas Extract in Ameliorating Cognitive-like Behavior Deficits in Ovariectomized Mice via Activation of Multiple Mechanisms

Postmenopausal women have a higher probability of experiencing cognitive alterations compared to men, suggesting that the decline in female hormones may contribute to cognitive deterioration. Thailand traditionally uses Tri-Kaysorn-Mas (TKM), a blend of three medicinal herbs, as a tonic to stimulate appetite and relieve dyspepsia. Due to its antioxidant and anti-acetylcholinesterase activities, we investigated the effects of TKM (50 and 100 mg/kg/day, p.o., for 8 weeks) on cognitive deficits and their underlying causes in an ovariectomized (OVX) mouse model of menopause. OVX mice showed cognitive impairment in the Y-maze, novel object recognition task (NORT), and Morris water maze (MWM) behavioral tests, along with atrophic changes to the uterus, altered levels of serum 17β-estradiol, and down-regulated expression of estrogen receptors (ERα and ERβ). These behavioral effects were reversed by TKM. TKM decreased malondialdehyde (MDA) levels and mitigated oxidative stress in the brain by enhancing the activity of superoxide dismutase (SOD) and catalase (CAT) and by up-regulating the antioxidant-related gene Nrf2 while down-regulating Keap1. TKM also counteracted OVX-induced neurodegeneration by enhancing the expression of the neurogenesis-related genes BDNF and CREB. The results indicate that TKM extract alleviates oxidative brain damage and neurodegeneration while enhancing cognitive behavior in OVX mice, significantly improving cognitive deficiencies related to menopause/ovariectomy through multiple targets.

The impact of resistance training on memory, gait and oxidative stress during periestropause in rats

Aging, especially in female, is complex, involving various factors such as reproductive sensitivity, cognitive and functional decline, and an imbalance in the redox system. This study aims to assess the effectiveness of long-term resistance training as a non-pharmacological strategy to mitigate the impairment of recognition memory, hippocampal redox state, and ambulation in aging female Wistar rats during the periestropause period. Thirty Wistar rats aged 17 months, in periestropause, were distributed into non-trained (NT) and resistance training (RT; stair climbing 3 times per week for 4 months) groups. Before (17 months) and after (21 months) of the RT period, the rats underwent tests for ambulation, elevated plus maze (EPM), open field, and object recognition. Biochemical and histological analyses were conducted on the hippocampus of these animals. Analysis of the results revealed that at 21 months, females in the NT group (21Mo/NT) exhibited a decreased in length (p=0.0458) and an increased in past width (p<0.0479) compared to their measurements at 17 months. However, after 4 months of RT, the female rats aged 21 months (21Mo/RT group) experienced changes in gait components, showing an increase in length (p<0.0008) and a decrease in stride width. Regarding memory, the object recognition test indicated potential cognitive improvement in 21Mo/RT animals, with significant interaction between intervention and age across all three stages of the test (total exploration time, p=0.0001; Test 1, p=0.0003; Test 2, p=0.0014). This response was notable compared to animals in the 21Mo/NT group, which showed a decline in memory capacity (p<0.01). The data showed a significant difference in relation to the age of the animals (p<0.01). The hippocampal redox state markers showed reduced lipid oxidative (p=0.028), catalase (p=0.022), and superoxide dismutase (p=0.0067) in the RT group compared to the NT group. Hippocampal cells from the 21Mo/RT group showed increased citrate synthase enzyme activity (p<0.05) and Nissl body staining (p<0.05). The results of this study demonstrate that RT performed during the periestropause phase leads to significant improvements in functional abilities, cognitive performance, and neuroplasticity in aging female rats.

Estrogen signalling and Alzheimer's disease: Decoding molecular mechanisms for therapeutic breakthrough

In females, Alzheimer's disease (AD) incidences increases as compared to males due to estrogen deficiency after menopause. Estrogen therapy is the mainstay therapy for menopause and associated complications. Estrogen, a hormone with multifaceted physiological functions, has been implicated in AD pathophysiology. Estrogen plays a crucial role in amyloid precursor protein (APP) processing and overall neuronal health by regulating various factors such as brain-derived neurotrophic factor (BDNF), intracellular calcium signalling, death domain-associated protein (Daxx) translocation, glutamatergic excitotoxicity, Voltage-Dependent Anion Channel, Insulin-Like Growth Factor 1 Receptor, estrogen-metabolising enzymes and apolipoprotein E (ApoE) protein polymorphisms. All these factors impact the physiology of postmenopausal women. Estrogen replacement therapies play an important treatment strategy to prevent AD after menopause. However, use of these therapies may lead to increased risks of breast cancer, venous thromboembolism and cardiovascular disease. Various therapeutic approaches have been used to mitigate the effects of estrogen on AD. These include hormone replacement therapy, Selective Estrogen Receptor Modulators (SERMs), Estrogen Receptor Beta (ERβ)-Selective Agonists, Transdermal Estrogen Delivery, Localised Estrogen Delivery, Combination Therapies, Estrogen Metabolism Modulation and Alternative Estrogenic Compounds like genistein from soy, a notable phytoestrogen from plant sources. However, mechanism via which these approaches modulate AD in postmenopausal women has not been explained earlier thoroughly. Present review will enlighten all the molecular mechanisms of estrogen and estrogen replacement therapies in AD. Along-with this, the association between estrogen, estrogen-metabolising enzymes and ApoE protein polymorphisms will also be discussed in postmenopausal AD.

The Effects of Estrogen on the Risk of Developing Dementia: A Cohort Study Using the UK Biobank Data

OBJECTIVES

The protective role of estrogen in the development of dementia remains uncertain. We investigated the role of lifetime cumulative exposure to estrogen in dementia in the UK Biobank.

METHODS

Reproductive characteristics, including estrogen length and history of surgery (hysterectomy/oophorectomy), were used as exposure variables. Cox Proportional Hazard models were used to estimate hazard ratios (HR) for the development of dementia.

RESULTS

A total of 273,260 female participants were included in this study. Compared to women with the shortest estrogen length, women with the longer estrogen length (38-42) had a 28% decreased risk of dementia (HR = 0.718, 95% confidence interval [CI] = 0.651-0.793). Women with later last age at estrogen exposure (50-52) had a 24% decreased risk for dementia (HR = 0.763, 95% CI = 0.695-0.839) compared to women with younger age at last estrogen exposure (≤45). Later age at menarche (≥15) was associated with a 12% increased risk for dementia (HR = 1.121, 95% CI = 1.018-1.234) compared to women with earlier age at menarche (≤12). Women with a history of surgery had an 8% increased risk of dementia (HR = 1.079, 95% CI = 1.002-1.164) compared to women without a history of surgery.

CONCLUSION

This study found that more prolonged exposure to estrogen (longer estrogen length and later age at last estrogen exposure) had a decreased risk for dementia, and shorter exposure to estrogen (later age at menarche and history of reproductive surgery) had an increased risk for dementia. Based on the results of this study, estrogen might have a protective role in women in the development of dementia.

Estradiol enhanced neuronal plasticity and ameliorated astrogliosis in human iPSC-derived neural models

Introduction

17β-Estradiol (E2) is a sex hormone that has been previously demonstrated to have neurotherapeutic effects on animal models of Alzheimer's disease (AD). However, clinical trials on E2 replacement therapy for preventing AD onset yielded inconsistent results. Therefore, it is imperative to clarify the therapeutic effects of E2 on human cells. In this study, we utilized induced pluripotent stem cells (iPSCs) derived from multiple AD donors to explore the therapeutic effects of E2 on the in vitro model of human cells.

Methods

We conducted a systematic review and meta-analysis using a random-effects model of the previously reported AD clinical trials to summarize the effects of E2 replacement therapy on AD prevention. Subsequently, we induced iPSCs from the donors of the healthy control (1210B2 line (female) and 201B7 line (female)), the familial AD (APP V717L line (female) and APP KM670/671NL line (female)), and the sporadic AD (UCSD-SAD3.7 line (APOE ε3/ε3) (male), UCSD-SAD7D line (APOE ε3/ε4) (male), and TMGH-1 line (APOE ε3/ε3) (female)), then differentiated to neurons. In addition to the mono-culture model of the neurons, we also examined the effects of E2 on the co-culture model of neurons and astrocytes.

Results

The meta-analysis of the clinical trials concluded that E2 replacement therapy reduced the risk of AD onset (OR, 0.69; 95 % confidence interval [CI], 0.53-0.91; I2 = 82 %). Neural models from the iPSCs of AD donors showed an increase in secreted amyloid-beta (Aβ) levels in the mono-culture model and an astrogliosis-like phenotype in the co-culture model. E2 treatment to the neuronal models derived from the iPSCs enhanced neuronal activity and increased neurite complexity. Furthermore, E2 treatment of the co-culture model ameliorated the astrogliosis-like phenotype. However, in contrast to the previous reports using mouse models, E2 treatment did not change AD pathogenesis, including Aβ secretion and phosphorylated tau (pTau) accumulation.

Conclusion

E2 treatment of the human cellular model did not impact Aβ secretion and pTau accumulation, but promoted neuronal plasticity and alleviated the astrogliosis-like phenotype. The limited effects of E2 may give a clue for the mixed results of E2 clinical trials.

Hyaluronic Acid Conjugated with 17β-Estradiol Effectively Alleviates Estropause-Induced Cognitive Deficits in Rats

Women are at a higher risk of cognitive impairments and Alzheimer's disease (AD), particularly after the menopause, when the estrous cycle becomes irregular and diminishes. Numerous studies have shown that estrogen deficiency, especially estradiol (E2) deficiency, plays a key role in this phenomenon. Recently, a novel polymeric drug, hyaluronic acid-17β-estradiol conjugate (HA-E2), has been introduced for the delivery of E2 to brain tissues. Studies have indicated that HA-E2 crosses the blood-brain barrier (BBB) and facilitates a prolonged E2 release profile while lowering the risk of estrogen-supplement-related side effects. In this study, we used ovariohysterectomy (OHE) rats, a postmenopausal cognitive deficit model, to explore the effect of a 2-week HA-E2 treatment (210 ng/kg body weight, twice a week) on the cholinergic septo-hippocampal innervation system, synaptic transmission in hippocampal pyramidal neurons and cognitive improvements. Our study revealed an 11% rise in choline acetyltransferase (ChAT) expression in both the medial septal nucleus (MS nucleus) and the hippocampus, along with a 14-18% increase in dendritic spine density in hippocampal pyramidal neurons, following HA-E2 treatment in OHE rats. These enhancements prompted the recovery of cognitive functions such as spatial learning and memory. These findings suggest that HA-E2 may prevent and improve estrogen-deficiency-induced cognitive impairment and AD.

Role of sex hormones in the effects of sleep deprivation on methamphetamine reward memory

Sleep deficiency is known as an important risk factor for relapse to drug abuse, especially for the powerful psychostimulant methamphetamine (METH). On the other hand, both drug addiction and sleep neurobiology are affected by sex hormones. We, therefore, aimed to examine the probable effects of sleep deprivation (SD) on methamphetamine (METH) reward memory in male and female rats. Moreover, we asked if sex hormones influence the effects of SD on METH reward memory. Adult male and female Wistar rats were divided into two main groups, sham and gonadectomized groups. Three weeks later, they were conditioned to receive METH (2 mg/kg, i.p.) in the conditioned place preference. METH reward memory was then reinstated following a 10-day extinction period. SD was induced for 72 h, either before or after extinction, in different groups. In gonadectomized animals, they daily received either subcutaneous administration of estrogen (5 μg/0.1 ml oil) or progesterone (2 mg/0.1 ml oil) or dihydrotestosterone (25 mg/0.1 ml oil) for thirteen days, from post-conditioning day to reinstatement session. We found that SD facilitated relapse to METH reward memory, depending on the time interval between SD and METH reinstatement. Furthermore, we found that estrogen and SD showed synergistic effects to facilitate METH reward memory, whereas testosterone and progesterone revealed inhibitory effects in the controls, but not in the SD, animals. Our findings would seem to suggest that sex hormones should be considered as determinant factors to manage METH abuse and relapse to METH seeking/taking behavior, especially for those with sleep deficiency.

Estrogen Receptor Signaling in Breast Cancer

Estrogen receptor (ER) signaling is a critical regulator of cell proliferation, differentiation, and survival in breast cancer (BC) and other hormone-sensitive cancers. In this review, we explore the mechanism of ER-dependent downstream signaling in BC and the role of estrogens as growth factors necessary for cancer invasion and dissemination. The significance of the clinical implications of ER signaling in BC, including the potential of endocrine therapies that target estrogens' synthesis and ER-dependent signal transmission, such as aromatase inhibitors or selective estrogen receptor modulators, is discussed. As a consequence, the challenges associated with the resistance to these therapies resulting from acquired ER mutations and potential strategies to overcome them are the critical point for the new treatment strategies' development.

Sex/gender differences in cognitive abilities

Sex/gender differences in cognitive sciences are riddled by conflicting perspectives. At the center of debates are clinical, social, and political perspectives. Front and center, evolutionary and biological perspectives have often focused on 'nature' arguments, while feminist and constructivist views have often focused on 'nurture arguments regarding cognitive sex differences. In the current narrative review, we provide a comprehensive overview regarding the origins and historical advancement of these debates while providing a summary of the results in the field of sexually polymorphic cognition. In so doing, we attempt to highlight the importance of using transdisciplinary perspectives which help bridge disciplines together to provide a refined understanding the specific factors that drive sex differences a gender diversity in cognitive abilities. To summarize, biological sex (e.g., birth-assigned sex, sex hormones), socio-cultural gender (gender identity, gender roles), and sexual orientation each uniquely shape the cognitive abilities reviewed. To date, however, few studies integrate these sex and gender factors together to better understand individual differences in cognitive functioning. This has potential benefits if a broader understanding of sex and gender factors are systematically measured when researching and treating numerous conditions where cognition is altered.

Sex representation in neurodegenerative and psychiatric disorders' preclinical and clinical studies

Many studies show the importance of biological sex for the onset, progression, and response to treatment in brain disorders. In line with these reports, health agencies have requested that all trials, both at the clinical and preclinical level, use a similar number of male and female subjects to correctly interpret the results. Despite these guidelines, many studies still tend to be unbalanced in the use of male and female subjects. In this review we consider three neurodegenerative disorders: Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis, and three psychiatric disorders: Depression, Attention Deficit Hyperactivity Disorder, and Schizophrenia. These disorders were chosen because of their prevalence and their recognized sex-specific differences in onset, progression, and response to treatment. Alzheimer's disease and Depression demonstrate higher prevalence in females, whereas Parkinson's Disease, Amyotrophic lateral sclerosis, Attention Deficit Hyperactivity Disorder, and schizophrenia show higher prevalence in males. Results from preclinical and clinical studies examining each of these disorders revealed sex-specific differences in risk factors, diagnostic biomarkers, and treatment response and efficacy, suggesting a role for sex-specific therapies in neurodegenerative and neuropsychiatric disorders. However, the qualitative analysis of the percentage of males and females enrolled in clinical trials in the last two decades shows that for most of the disorders, there is still a sex bias in the patients' enrolment.

Association of earlier age at menopause with risk of incident dementia, brain structural indices and the potential mediators: a prospective community-based cohort study

BACKGROUND

To date, there is no homogeneous evidence of whether earlier age at menopause is associated with incident dementia. In addition, the underlying mechanism and driven mediators are largely unknown. We aimed to fill these knowledge gaps.

METHODS

This community-based cohort study included 154,549 postmenopausal women without dementia at enrolment (between 2006 and 2010) from the UK Biobank who were followed up until June 2021. We followed up until June 2021. Age at menopause was entered as a categorical variable (<40, 40-49, and ≥50 years) with ≥50 years taken as a reference. The primary outcome was all-cause dementia in a time-to-event analysis and the secondary outcomes included Alzheimer's disease, vascular dementia, and other types of dementia. In addition, we investigated the association between magnetic resonance (MR) brain structure indices with earlier menopause, and explored the potential underlying driven mediators on the relationship between earlier menopause and dementia.

FINDINGS

2266 (1.47%) dementia cases were observed over a median follow-up period of 12.3 years. After adjusting for confounders, women with earlier menopause showed a higher risk of all-cause dementia compared with those ≥50 years (adjusted-HRs [95% CIs]: 1.21 [1.09-1.34] and 1.71 [1.38-2.11] in the 40-49 years and <40 years groups, respectively; P for trend <0.001). No significant interactions between earlier menopause and polygenic risk score, cardiometabolic factors, type of menopause, or hormone-replacement therapy strata were found. Earlier menopause was negatively associated with brain MR global and regional grey matter indices, and positively associated with white matter hyperintensity. The relationship between earlier menopause and dementia was partially mediated by menopause-related comorbidities including sleep disturbance, mental health disorder, frailty, chronic pain, and metabolic syndrome, with the proportion (95% CI) of mediation effect being 3.35% (2.18-5.40), 1.38% (1.05-3.20), 5.23% (3.12-7.83), 3.64% (2.88-5.62) and 3.01% (2.29-4.40), respectively. Multiple mediator analysis showed a combined effect being 13.21% (11.11-18.20).

INTERPRETATION

Earlier age at menopause was associated with risk of incident dementia and deteriorating brain health. Further studies are warranted to clarify the underlying mechanisms by which earlier age at menopause is linked to an increased risk of dementia, and to determine public health strategies to attenuate this association.

FUNDING

National Natural Science Foundation of China, the Science and Technology Program of Guangzhou, the Key Area Research and Development Program of Guangdong Province, the China Postdoctoral Science Foundation, and the Guangdong Basic and Applied Basic Research Foundation.

Neuroprotective effects of novel compound FMDB on cognition, neurogenesis and apoptosis in APP/PS1 transgenic mouse model of Alzheimer's disease

Clinical and experimental studies have shown that the sharp reduction of estrogen is one of the important reasons for the high incidence of Alzheimer's disease (AD) in elderly women, but there is currently no such drug for treatment of AD. Our group first designed and synthesized a novel compound R-9-(4fluorophenyl)-3-methyl-10,10,-Hydrogen-6-hydrogen-benzopyran named FMDB. In this study, our aim is to investigate the neuroprotective effects and mechanism of FMDB in APP/PS1 transgenic mice. 6 months old APP/PS1 transgenic mice were intragastrical administered with FMDB (1.25, 2.5 and 5 mg/kg) every other day for 8 weeks. LV-ERβ-shRNA was injected bilaterally into the hippocampus of APP/PS1 mice to knockdown estrogen receptor β (ERβ). We found that FMDB ameliorated cognitive impairment in the Morris water maze and novel object recognition tests, increased hippocampal neurogenesis and prevented hippocampal apoptotic responses in APP/PS1 mice. Importantly, FMDB activated nuclear ERβ mediated CBP/p300, CREB and brain-derived neurotrophic factor (BDNF) signaling, and membrane ERβ mediated PI3K/Akt, CREB and BDNF signaling in the hippocampus. Our study demonstrated the contributions and mechanism of FMDB to cognition, neurogenesis and apoptosis in APP/PS1 mice. These lay the experimental foundation for the development of new anti-AD drugs.

Epigenetic Modifications by Estrogen and Androgen in Alzheimer's Disease

For the development and maintenance of neuron networks in the brain, epigenetic mechanisms are necessary, as indicated by recent findings. This includes some of the high-order brain processes, such as behavior and cognitive functions. Epigenetic mechanisms could influence the pathophysiology or etiology of some neuronal diseases, altering disease susceptibility and therapy responses. Recent studies support epigenetic dysfunctions in neurodegenerative and psychiatric conditions, such as Alzheimer's disease (AD). These dysfunctions in epigenetic mechanisms also play crucial roles in the transgenerational effects of the environment on the brain and subsequently in the inheritance of pathologies. The possible role of gonadal steroids in the etiology and progression of neurodegenerative diseases, including Alzheimer's disease, has become the subject of a growing body of research over the last 20 years. Recent scientific findings suggest that epigenetic changes, driven by estrogen and androgens, play a vital role in brain functioning. Therefore, exploring the role of estrogen and androgen-based epigenetic changes in the brain is critical for the deeper understanding of AD. This review highlights the epigenetic modifications caused by these two gonadal steroids and the possible therapeutic strategies for AD.

The Impacts of Sex Differences and Sex Hormones on Fear Extinction

Fear extinction memories are strongly modulated by sex and hormonal status, but the exact mechanisms are still being discovered. In humans, there are some basal and task-related features in which male and female individuals differ in fear conditioning paradigms. However, analyses considering the effects of sex hormones demonstrate a role for estradiol in fear extinction memory consolidation. Translational studies are taking advantage of the convergent findings between species to understand the brain structures implicated. Nevertheless, the human brain is complex and the transfer of these findings into the clinics remains a challenge. The promising advances in the field together with the standardization of fear extinction methodologies in humans will benefit the design of new personalized therapies.

Estrogens as a Possible Therapeutic Strategy for the Management of Neuroinflammation and Neuroprotection in COVID-19

The Coronavirus disease 2019 (COVID-19) affects several tissues, including the central and peripheral nervous system. It has also been related to signs and symptoms that suggest neuroinflammation with possible effects in the short, medium, and long term. Estrogens could have a positive impact on the management of the disease, not only due to its already known immunomodulator effect, but also activating other pathways that may be important in the pathophysiology of COVID-19, such as the regulation of the virus receptor and its metabolites. In addition, they can have a positive effect on neuroinflammation secondary to pathologies other than COVID-19. The aim of this study is to analyze the molecular mechanisms that link estrogens with their possible therapeutic effect for neuroinflammation related to COVID-19. Advanced searches were performed in scientific databases as Pub- Med, ProQuest, EBSCO, the Science Citation index, and clinical trials. Estrogens have been shown to participate in the immune modulation of the response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In addition to this mechanism, we propose that estrogens can regulate the expression and activity of the Angiotensin-converting enzyme 2 (ACE2), reestablishing its cytoprotective function, which may be limited by its interaction with SARS-CoV-2. In this proposal, estrogens and estrogenic compounds could increase the synthesis of Angiotensin-(1-7) (Ang-(1-7)) that acts through the Mas receptor (MasR) in cells that are being attacked by the virus. Estrogens can be a promising, accessible, and low-cost treatment for neuroprotection and neuroinflammation in patients with COVID-19, due to its direct immunomodulatory capacity in decreasing cytokine storm and increasing cytoprotective capacity of the axis ACE2/Ang (1-7)/MasR.

Antipsychotic-induced movement disorders: integrative review

Objective: To identify movement disorders induced by antipsychotics. Methods: We selected clinical trials from MEDLINE and LILACS databases without publication date restriction. Studies of antipsychotics as a pharmacological intervention, compared or not to other interventions were included (combined treatments were not included). The primary outcome was movement disorders. Two independent reviewers analyzed the studies and summarized them in an electronic spreadsheet. We assessed the quality of the selected studies using the PEDro scale. Results: Five studies were included in this review. In these studies, it was possible to identify the main psychiatric symptoms and their severity, as well as dyskinetic movements. When a reduction in dyskinetic movements was observed in treatments with both atypical and typical antipsychotics, there were adverse effects. Those included excessive sedation, loss of body mass, vomiting, and leukocytopenia. Conclusion: This study verified the findings in literature on the effects of antipsychotics, including the type of medication, dosage, and form of administration, as well as instruments used to assess the outcome related to movement disorders. It was not possible to determine the best therapeutic dose for managing the disorders due to the significant distinction in dosages and medications. All five studies had some effect related to the drug use or its withdrawal.

Estradiol and Estrogen-like Alternative Therapies in Use: The Importance of the Selective and Non-Classical Actions

Estrogen is one of the most important female sex hormones, and is indispensable for reproduction. However, its role is much wider. Among others, due to its neuroprotective effects, estrogen protects the brain against dementia and complications of traumatic injury. Previously, it was used mainly as a therapeutic option for influencing the menstrual cycle and treating menopausal symptoms. Unfortunately, hormone replacement therapy might be associated with detrimental side effects, such as increased risk of stroke and breast cancer, raising concerns about its safety. Thus, tissue-selective and non-classical estrogen analogues have become the focus of interest. Here, we review the current knowledge about estrogen effects in a broader sense, and the possibility of using selective estrogen-receptor modulators (SERMs), selective estrogen-receptor downregulators (SERDs), phytoestrogens, and activators of non-genomic estrogen-like signaling (ANGELS) molecules as treatment.

Gender differences in progressive supranuclear palsy

The gender differences in progressive supranuclear palsy (PSP) are not extensively studied. The objective of this study was to determine the gender differences in the phenotypic expression and progression in PSP. We did a retrospective review of medical records of patients diagnosed with PSP over a 21-year period. The interval between disease onset and attainment of the five clinical disability milestones namely wheel chair dependency, unintelligible speech, severe dysphagia, severe cognitive impairment and urinary catheterization was used to determine the progression. Data was analysed from the case records of 334 patients with PSP. 209 patients (62.2%) were male and 125 (37.4%) among the patients were women (male:female ratio = 1.6:1). Males had older age at onset with longer duration of illness at time of presentation. Tremors were more common, PSP-P phenotype was more frequent and time to attain wheelchair dependency was earlier in males. Falls within 1 year of disease onset, apathy and executive dysfunction were more frequent and time to attain unintelligible speech, severe dysphagia and cognitive impairment were earlier in females. This study in a large cohort of clinically diagnosed cases of PSP has showed that gender differences exist in PSP in terms of clinical characteristics, progression of the disease.

The Association Between HIV Status, Estradiol, and Sex Hormone Binding Globulin Among Premenopausal Women in the Women's Interagency HIV Study

Background: Characterizing estradiol among women with HIV may have implications for breast cancer and cardiovascular disease risk but has not been adequately explored. We quantified differences in total (E2), free (FE2) estradiol, and sex hormone binding globulin (SHBG) by HIV and viral suppression status. Methods: Women from a substudy (2003-2006) within the Women's Interagency HIV Study (IRB approved at each participating site) were included if they reported: a period in the last six months, were not pregnant/breastfeeding, no oophorectomy, and no exogenous hormone use in the prior year. Serum was collected on days 2-4 of the menstrual cycle. We assessed differences in biomarkers at 25th, 50th, and 75th percentiles by HIV and viral suppression status using weighted quantile regression. Results: Among 643 women (68% with HIV) median age was 37 years. All E2 percentiles were significantly (p < 0.05) lower in women with suppressed viral load versus women without HIV (4-10 pg/mL). The 25th and 50th percentile of E2 were 4-5 pg/mL lower in women with unsuppressed viral load compared to women without HIV (p < 0.05). The 25th and 50th percentile of SHBG was significantly higher in women with unsuppressed viral load compared to women without HIV (10 and 12 nmol/L, respectively). There were no consistent differences in estradiol or SHBG by suppression status. Conclusions: There were no differences in FE2 but significantly lower E2 and higher SHBG among women with HIV versus without HIV. Further research is merited in a large contemporary sample to clarify the clinical implications of these findings.

Ovariectomy-induced hormone deprivation aggravates Aβ1-42 deposition in the basolateral amygdala and cholinergic fiber loss in the cortex but not cognitive behavioral symptoms in a triple transgenic mouse model of Alzheimer's disease

Alzheimer's disease is the most common type of dementia, being highly prevalent in elderly women. The advanced progression may be due to decreased hormone synthesis during post-menopause as estradiol and progesterone both have neuroprotective potentials. We aimed to confirm that female hormone depletion aggravates the progression of dementia in a triple transgenic mouse model of Alzheimer's disease (3xTg-AD). As pathological hallmarks are known to appear in 6-month-old animals, we expected to see disease-like changes in the 4-month-old 3xTg-AD mice only after hormone depletion. Three-month-old female 3xTg-AD mice were compared with their age-matched controls. As a menopause model, ovaries were removed (OVX or Sham surgery). After 1-month recovery, the body composition of the animals was measured by an MRI scan. The cognitive and anxiety parameters were evaluated by different behavioral tests, modeling different aspects (Y-maze, Morris water maze, open-field, social discrimination, elevated plus maze, light-dark box, fox odor, operant conditioning, and conditioned fear test). At the end of the experiment, uterus was collected, amyloid-β accumulation, and the cholinergic system in the brain was examined by immunohistochemistry. The uterus weight decreased, and the body weight increased significantly in the OVX animals. The MRI data showed that the body weight change can be due to fat accumulation. Moreover, OVX increased anxiety in control, but decreased in 3xTg-AD animals, the later genotype being more anxious by default based on the anxiety z-score. In general, 3xTg-AD mice moved less. In relation to cognition, neither the 3xTg-AD genotype nor OVX surgery impaired learning and memory in general. Despite no progression of dementia-like behavior after OVX, at the histological level, OVX aggravated the amyloid-β plaque deposition in the basolateral amygdala and induced early cholinergic neuronal fiber loss in the somatosensory cortex of the transgenic animals. We confirmed that OVX induced menopausal symptoms. Removal of the sexual steroids aggravated the appearance of AD-related alterations in the brain without significantly affecting the behavior. Thus, the OVX in young, 3-month-old 3xTg-AD mice might be a suitable model for testing the effect of new treatment options on structural changes; however, to reveal any beneficial effect on behavior, a later time point might be needed.

Spontaneous intracerebral hemorrhage among hypertensive patients in Saudi Arabia: Study from a tertiary center

Background:

Objectives:

Patients and Methods:

Results:

Conclusion:

Nuclear Receptors in Myocardial and Cerebral Ischemia-Mechanisms of Action and Therapeutic Strategies

Nearly 18 million people died from cardiovascular diseases in 2019, of these 85% were due to heart attack and stroke. The available therapies although efficacious, have narrow therapeutic window and long list of contraindications. Therefore, there is still an urgent need to find novel molecular targets that could protect the brain and heart against ischemia without evoking major side effects. Nuclear receptors are one of the promising targets for anti-ischemic drugs. Modulation of estrogen receptors (ERs) and peroxisome proliferator-activated receptors (PPARs) by their ligands is known to exert neuro-, and cardioprotective effects through anti-apoptotic, anti-inflammatory or anti-oxidant action. Recently, it has been shown that the expression of aryl hydrocarbon receptor (AhR) is strongly increased after brain or heart ischemia and evokes an activation of apoptosis or inflammation in injury site. We hypothesize that activation of ERs and PPARs and inhibition of AhR signaling pathways could be a promising strategy to protect the heart and the brain against ischemia. In this Review, we will discuss currently available knowledge on the mechanisms of action of ERs, PPARs and AhR in experimental models of stroke and myocardial infarction and future perspectives to use them as novel targets in cardiovascular diseases.

Sex Selection Bias in Schizophrenia Antipsychotic Trials—An Update Systematic Review

The lack of female participation in antipsychotic trials for schizophrenia poses an important issue regarding its applicability, with direct and real-life repercussions to clinical practice. Here, our aim is to systematically review the sampling sex bias among randomized clinical trials (RCTs) of second-generation antipsychotics—namely risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole—as an update to a previous 2005 review. We searched MEDLINE and the Cochrane database for studies published through 7 September 2020 that assessed adult samples of at least 50 subjects with a diagnosis of schizophrenia, schizophrenia spectrum disorder, or broad psychosis, in order to investigate the percentage of women recruited and associated factors. Our review included 148 RCTs, published from 1993 to 2020, encompassing 43,961 subjects. Overall, the mean proportion of women was 34%, but only 17 trials included 50% or more females. Younger samples, studies conducted in North America, pharmaceutical funding and presence of specific exclusion criteria for women (i.e., pregnancy, breast-feeding or lack of reliable contraceptive) were associated with a lower prevalence of women in the trials. Considering the possible different effects of antipsychotics in both sexes, and our lack of knowledge on the subject due to sampling bias, it is imperative to expand actions aimed at bridging this gap.

The Role of Estradiol in Traumatic Brain Injury: Mechanism and Treatment Potential

Patients surviving traumatic brain injury (TBI) face numerous neurological and neuropsychological problems significantly affecting their quality of life. Extensive studies over the past decades have investigated pharmacological treatment options in different animal models, targeting various pathological consequences of TBI. Sex and gender are known to influence the outcome of TBI in animal models and in patients, respectively. Apart from its well-known effects on reproduction, 17β-estradiol (E2) has a neuroprotective role in brain injury. Hence, in this review, we focus on the effect of E2 in TBI in humans and animals. First, we discuss the clinical classification and pathomechanism of TBI, the research in animal models, and the neuroprotective role of E2. Based on the results of animal studies and clinical trials, we discuss possible E2 targets from early to late events in the pathomechanism of TBI, including neuroinflammation and possible disturbances of the endocrine system. Finally, the potential relevance of selective estrogenic compounds in the treatment of TBI will be discussed.

Puerarin suppresses MPP+/MPTP-induced oxidative stress through an Nrf2-dependent mechanism

In this study, we hypothesized that anti-parkinsonian effect of puerarin is attributable to its antioxidant properties via Nrf2-dependent glutathione (GSH) biosynthesis mechanism. Experimentally, we found that puerarin attenuated 1-methyl-4-phenylpyridinium (MPP⁺)-induced oxidative stress through elevating biosynthetic capacity of GSH in PC12 cells. Mechanistically, puerarin suppressed Fyn phosphorylation by GSK-3β-dependent mechanism in MPP⁺-challenged PC12 cells. Furthermore, puerarin induced accumulation of Nrf2 in the nucleus via inhibiting its nuclear exclusion. In parallel, puerarin up-regulated antioxidant response element (ARE)-driven catalytic subunits from glutamate cysteine ligase (GCLc) expression at levels of transcription and translation. Most interestingly, pharmacological inhibitor of GSK-3β or Fyn shRNA blocked puerarin-induced Nrf2 activation in MPP⁺-challenged PC12 cells. Concomitantly, puerarin ameliorated motor deficits and inhibited oxidative stress in the ventral midbrain in MPTP-intoxicated wild-type (WT) mice, but failed to attenuate MPTP neurotoxicity and up-regulate GCLc gene in Nrf2-knockout (Nrf2^-/-) mice, suggesting that anti-parkinsonian effect of puerarin was dependent on Nrf2. Additionally, puerarin regulated Fyn and GSK-3β phosphorylation in the ventral midbrain in MPTP-intoxicated WT mice. Collectively, the results of the study provide molecular insights into the potential therapeutic action of puerarin in Parkinson's disease, suggesting that puerarin may be a promising candidate for the treatment of Parkinson's disease.

Estradiol/GPER affects the integrity of mammary duct-like structures in vitro

High estrogen concentration leads to an inflammatory reaction in the mammary gland tissue in vivo; however, the detailed mechanism underlying its specific effects on the breast duct has not been fully clarified. We used 3D-cultured MCF-10A acini as a breast duct model and demonstrated various deleterious effects of 17-β estradiol (E2), including the destruction of the basement membrane surrounding the acini, abnormal adhesion between cells, and cell death via apoptosis and pyroptosis. Moreover, we clarified the mechanism underlying these phenomena: E2 binds to GPER in MCF-10A cells and stimulates matrix metalloproteinase 3 (MMP-3) and interleukin-1β (IL-1β) secretion via JNK and p38 MAPK signaling pathways. IL-1β activates the IL-1R1 signaling pathway and induces continuous MMP-3 and IL-1β secretion. Collectively, our novel findings reveal an important molecular mechanism underlying the effects of E2 on the integrity of duct-like structures in vitro. Thus, E2 may act as a trigger for ductal carcinoma transition in situ.

Schizophrenia and Sex Hormones: What Is the Link?

The involvement of gonadal hormones in the pathogenesis of schizophrenia has long been suspected because the psychosis differs in women and men and the illness first makes its appearance shortly after puberty. Changes in sex hormones have been linked with increased vulnerability to mood disorders in women, while testosterone have been associated with increased sexual drive and aggressiveness in men as well as women. Some studies have found abnormal levels of estrogens and testosterone in schizophrenia patients, but the results have been inconsistent and sometimes attributed to the hyperprolactinemia effect of antipsychotics, which may interfere with sex hormones production. The purpose of this review is to present the current knowledge on the link between blood levels of sex-hormones in women during the various stages of the female reproductive life (i.e. puberty, menstrual cycle, pregnancy, contraception, and menopause) and the course of schizophrenia. We also attempt to optimize the clinical approach to women with schizophrenia at these different stages.

The role of neuronal nitric oxide and its pathways in the protection and recovery from neurotoxin-induced de novo hypokinetic motor behaviors in the embryonic zebrafish (Danio rerio)

Neuronal nitric oxide (nNO) has been shown to affect motor function in the brain. Specifically, nNO acts in part through regulation of dopamine (DA) release, transporter function, and the elicitation of neuroprotection/neurodegeneration of neurons in conditions such as Parkinson's disease (PD). Recently, the zebrafish has been proposed to be a new model for the study of PD since neurotoxin damage to their nigrostriatal-like neurons exhibit PD-like motor dysfunctions similar to those of mammalian models and human patients. Results from this study demonstrate that treatment of 5 days post fertilization (dpf) fish with a nNO synthase inhibitor as a co-treatment with 6-OHDA facilitates long-term survival and accelerates the recovery from 6-OHDA-induced hypokinesia-like symptoms. These findings are unique in that under conditions of neurotoxin-induced stress, the inhibition of the NO-related S-nitrosylation indirect pathway dramatically facilitates recovery from 6-OHDA treatment but inhibition of the NO-sGC-cGMP direct pathway is essential for survival in 5 dpf treated fish. In conclusion, these results indicate that nNOS and the inhibition of the NO-linked S-nitrosylation pathway plays an important role in antagonizing the protection and recovery of fish from neurotoxin treatment. These data begin to help in the understanding of the role of NO as a neuroprotectant in dopaminergic pathways, particularly those that influence motor dysfunctions.

Maternal di-(2-ethylhexyl) phthalate exposure inhibits cerebellar granule precursor cell proliferation via down-regulating the Shh signaling pathway in male offspring

Di-(2-ethylhexyl) phthalate (DEHP) is an endocrine disrupting chemical (EDC) widely used as a plasticizer in many materials. Epidemiological investigations have shown that DEHP exposure during early development is related to cerebellar-related adverse neurodevelopmental outcomes. However, animal studies involving the effect of DEHP exposure on cerebellar development have rarely been reported and the potential mechanisms are unclear. The aim of this study was to investigate the effect of maternal DEHP exposure on the proliferation of cerebellar granule cell precursor cells (GCPs) and the mechanisms involved. Wistar rats were randomly assigned to four exposure groups and given 0, 30, 300, or 750 mg/kg/d DEHP by intragastric administration from gestational day (GD) 0 to postnatal day (PN) 21. Exposure to 300 and 750 mg/kg/d DEHP restrained GCPs proliferation and impaired neurodevelopment for males. Furthermore, exposure to 300 and 750 mg/kg/d DEHP decreased male pups protein expressions and mRNA levels of molecules related to proliferation, including Shh, Gli1, N-Myc, CyclinD1. In addition, the estrogen level and aromatase expression also reduced in male pups after maternal exposure to DEHP. However, effects on females were not obvious. These results suggested that 300 and 750 mg/kg/d DEHP exposure inhibit the proliferation of GCPs in male offspring and ultimately contribute to the impairment of neuromotor development. This, may be caused by the down-regulation of Shh signaling. And the susceptibility of male offspring to DEHP exposure may be attributed to the decreased estrogen level and aromatase expression in male pup's cerebellum.

Translational Significance of Selective Estrogen Receptor Modulators in Psychiatric Disorders

Accumulating data from various clinical trial studies suggests that adjuvant therapy with ovarian hormones (estrogens) could be effective in reducing cognitive deficit and psychopathological symptoms in women with psychiatric disorders. However, estrogen therapy poses serious limitations and health issues including feminization in men and increased risks of thromboembolism, hot flashes, breast hyperplasia, and endometrium hyperplasia when used for longer duration in older women (aged ≥ 60 years) or in women who have genetic predispositions. On the other hand, selective estrogen receptor modulators (SERMs), which may (or may not) carry some risks of hot flashes, thromboembolism, breast hyperplasia, and endometrial hyperplasia, are generally devoid of feminization effect. In clinical trial studies, adjuvant therapy with tamoxifen, a triphenylethylene class of SERM, has been found to reduce the frequency of manic episodes in patients with bipolar disorder, whereas addition of raloxifene, a benzothiophene class of SERM, to regular doses of antipsychotic drugs has been found to reduce cognitive deficit and psychological symptoms in men and women with schizophrenia, including women with treatment refractory psychosis. These outcomes together with potent neurocognitive, neuroprotective, and cardiometabolic properties suggest that SERMs could be the potential targets for designing effective and safer therapies for psychiatric disorders.

Prenatal exposure to benzophenone-3 (BP-3) induces apoptosis, disrupts estrogen receptor expression and alters the epigenetic status of mouse neurons

Current evidence indicates that benzophenone-3 (BP-3) can pass through the placental and blood-brain barriers and thus can likely affect infant neurodevelopment. Despite widespread exposure, data showing the effects of BP-3 on the developing nervous system are scarce. This study revealed for the first time that prenatal exposure to BP-3 led to apoptosis and neurotoxicity, altered the levels of estrogen receptors (ERs) and changed the epigenetic status of mouse neurons. In the present study, subcutaneous injections of pregnant mice with BP-3 at 50 mg/kg, which is an environmentally relevant dose, evoked activation of caspase-3 and lactate dehydrogenase (LDH) release as well as substantial loss of mitochondrial membrane potential in neocortical cells of their embryonic offspring. Apoptosis-focused microarray analysis of neocortical cells revealed up-regulation of 22 genes involved in apoptotic cell death. This effect was supported by increased BAX and CASP3 mRNA and protein levels, as evidenced by qPCR, ELISAs and western blots. BP-3-induced apoptosis and neurotoxicity were accompanied by decreases in the mRNA and protein expression levels of ESR1 and ESR2 (also known as ERα and ERβ), with a simultaneous increase in GPER1 (also known as GPR30) expression. In addition to the demonstration that treatment of pregnant mice with BP-3 induced apoptosis, caused neurotoxicity and altered ERs expression levels in neocortical cells of their embryonic offspring, we showed that prenatal administration of BP-3 inhibited global DNA methylation as well as reduced DNMTs activity. BP-3 also caused specific hypomethylation of the genes Gper1 and Bax, an effect that was accompanied by increased mRNA and protein expression levels. In addition, BP-3 caused hypermethylation of the genes Esr1, Esr2 and Bcl2, which could explain the reduced mRNA and protein levels of the estrogen receptors. This study demonstrated for the first time that prenatal exposure to BP-3 caused severe neuronal apoptosis that was accompanied by impaired ESR1/ESR2 expression, enhanced GPER1 expression, global DNA hypomethylation and altered methylation statuses of apoptosis-related and ERs genes. We suggest that the effects of BP-3 in embryonic neurons may be the fetal basis of the adult onset of nervous system disease.

Pharmacotherapy for schizophrenia in postmenopausal women

INTRODUCTION

Reduced estrogen levels at menopause mean a loss of the neuroprotection that is conferred, from puberty until menopause, on women with schizophrenia. The postmenopausal stage of schizophrenia requires therapeutic attention because women with this diagnosis almost invariably experience increased symptoms and increased side effects at this time. So far, few targeted therapies have been successfully developed.

AREAS COVERED

This non-systematic, narrative review is based on the relevant published literature indexed in PubMed. A digital search was combined with a manual check of references from studies in the field of gender differences, menopause and schizophrenia. Aside from the inclusion of a few early classic papers, the review focuses on 21st century basic, psychopharmacologic, and clinical literature on the treatment of women with schizophrenia after menopause.

EXPERT OPINION

Beyond a relatively low dose threshold, all antipsychotic medications have adverse effects, which become more prominent for women at the time of menopause. Estrogen modulators may not help all symptoms of schizophrenia but are, nevertheless, relatively safe and, when used as adjuncts, help to keep antipsychotic doses low, thus reducing the side effect burden. The field is currently moving towards precision medicine and individual genetic profiles will help to determine the efficacy of available treatments in the future.

Lifetime exposure to estrogen and progressive supranuclear palsy: Environmental and Genetic PSP study

BACKGROUND

Studies suggesting a protective effect of estrogen in neurodegenerative diseases prompted us to investigate this relationship in progressive supranuclear palsy (PSP).

METHODS

This case-control study evaluated the self-reported reproductive characteristics and estrogen of 150 women with PSP and 150 age-matched female controls who participated in the Environmental Genetic-PSP study. Conditional logistic regression models were generated to examine associations of PSP with estrogen.

RESULTS

There was no association between years of estrogen exposure duration and PSP. There was a suggestion of an inverse association between composite estrogen score and PSP that did not reach statistical significance (P = .06). Any exposure to estrogen replacement therapy halved the risk of PSP (odds ratio = 0.52; 95% confidence interval = 0.30-0.92; P = .03). Among PSP cases, earlier age at menarche was associated with better performance on Hoehn and Yahr stage (β = -0.60; SE = 0.26; P = .02) and Unified Parkinson's Disease Rating Scale II score (β = -5.19; SE = 2.48; P = .04) at clinical examination.

CONCLUSIONS

This case-control study suggests a protective role of lifetime estrogen exposure in PSP. Future studies will be needed to confirm this association. © 2018 International Parkinson and Movement Disorder Society.

Treating schizophrenia during menopause

OBJECTIVE

The aim of this review is to examine three questions: What are the risks and benefits of treating women with schizophrenia with hormone therapy (HT) at menopause? Should the antipsychotic regimen be changed at menopause? Do early- and late-onset women with schizophrenia respond differently to HT at menopause?

METHODS

MEDLINE databases for the years 1990 to 2016 were searched using the following interactive terms: schizophrenia, gender, menopause, estrogen, and hormones. The selected articles (62 out of 800 abstracts) were chosen on the basis of their applicability to the objectives of this targeted narrative review.

RESULTS

HT during the perimenopause in women with schizophrenia ameliorates psychotic and cognitive symptoms, and may also help affective symptoms. Vasomotor, genitourinary, and sleep symptoms are also reduced. Depending on the woman's age and personal risk factors and antipsychotic side effects, the risk of breast cancer and cardiovascular disease may be increased. Antipsychotic types and doses may need to be adjusted at menopause, as may be the mode of administration.

CONCLUSIONS

Both HT and changes in antipsychotic management should be considered for women with schizophrenia at menopause. The question about differences in response between early- and late-onset women cannot yet be answered.

GPER Agonist G1 Attenuates Neuroinflammation and Dopaminergic Neurodegeneration in Parkinson Disease

OBJECTIVE

Epidemiological studies have shown that women of reproductive age have much less possibility of developing Parkinson disease (PD) than men. The beneficial effect of estrogen also has been well-described in both culture and animal models of PD. G protein-coupled estrogen receptor (GPER) is a membrane-associated estrogen receptor, and displayed a neuroprotective role in a mouse model of PD. Since GPER is highly expressed in microglia, we speculate that GPER mediates the neuroprotective function of estradiol through suppressing the neuroinflammation of PD.

METHODS

We investigated the effects of GPER agonist G1 and GPER antagonist G15 on the neurodegeneration of dopaminergic neuron, the activation of microglia, and the production of IL-1β, TNF-α, and IL-6 in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced animal model of parkinsonism. Furthermore, we confirmed the effects of GPER activation on the production of IL-1β, TNF-α, and IL-6 in an in vitro MPP+ model in BV2 microglial cells.

RESULTS

After 12-day treatment with G1, mice showed an increase in the number of tyrosine hydroxylase-immunoreactive cells, reduced activation of microglia, and the abatement of proinflammatory cytokines, and the anti-inflammatory effect of G1 was abolished by G15. Meanwhile, in vitro studies demonstrated that GPER activation also reduced the release of proinflammatory cytokines from BV2 microglial cells after MPP+ stimulation.

CONCLUSION

Our data suggest that GPER mediates the anti-neuroinflammatory effect of estrogen in experimental PD progression.

Sex Steroids Influence Brain-Derived Neurotropic Factor Secretion From Human Airway Smooth Muscle Cells

Brain derived neurotropic factor (BDNF) is emerging as an important player in airway inflammation, remodeling, and hyperreactivity. Separately, there is increasing evidence that sex hormones contribute to pathophysiology in the lung. BDNF and sex steroid signaling are thought to be intricately linked in the brain. There is currently little information on BDNF and sex steroid interactions in the airway but is relevant to understanding growth factor signaling in the context of asthma in men versus women. In this study, we assessed the effect of sex steroids on BDNF expression and secretion in human airway smooth muscle (ASM). Human ASM was treated with estrogen (E2 ) or testosterone (T, 10 nM each) and intracellular BDNF and secreted BDNF measured. E2 and T significantly reduced secretion of BDNF; effects prevented by estrogen and androgen receptor inhibitor, ICI 182,780 (1 μM), and flutamide (10 μM), respectively. Interestingly, no significant changes were observed in intracellular BDNF mRNA or protein expression. High affinity BDNF receptor, TrkB, was not altered by E2 or T. E2 (but not T) significantly increased intracellular cyclic AMP levels. Notably, Epac1 and Epac2 expression were significantly reduced by E2 and T. Furthermore, SNARE complex protein SNAP25 was decreased. Overall, these novel data suggest that physiologically relevant concentrations of E2 or T inhibit BDNF secretion in human ASM, suggesting a potential interaction of sex steroids with BDNF in the airway that is different from brain. The relevance of sex steroid-BDNF interactions may lie in their overall contribution to airway diseases such as asthma.