Estrogen actions in the brain and the basis for differential action in men and women: a case for sex-specific medicines

Relation between child maltreatment and human capital: results from a population-based birth cohort

This study aimed to investigate the association between child maltreatment and human capital, measured by intelligence quotient (IQ) at age 18 years and schooling at age 22 years in 3,736 members from a population-based birth cohort in Southern Brazil. A multiple linear regression was used to assess the association between child maltreatment and human capital measurements. Physical and emotional abuse and physical neglect occurring up to 15 years of age were considered child maltreatment. Physical neglect was associated with lower IQ scores in women (β = -4.40; 95%CI: -6.82; -1.99) and men (β = -2.58; 95%CI: -5.17; -0.01) and lower schooling for all sexes: women (β = -1.19; 95%CI: -1.64; -0.74) and men (β = -0.82; 95%CI: -1.34; -0.30). Moreover, men who had experienced one type of child maltreatment and women who had experienced two or more types had lower years of schooling at 22 years (β = -0.41; 95%CI: -0.73; -0.89 and β = -0.57; 95%CI: -0.91; -0.22, respectively) than those who suffered no kind of maltreatment. Efforts to improve future educational and cognitive outcomes must include early prevention and intervention strategies for child maltreatment.

Do Sex and Gender Have Separate Identities?

The largely binary nature of biological sex and its conflation with the socially constructed concept of gender has created much strife in the last few years. The notion of gender identity and its differences and similarities with sex have fostered much scientific and legal confusion and disagreement. Settling the debate can have significant repercussions for science, medicine, legislation, and people's lives. The present review addresses this debate though different levels of analysis (i.e., genetic, anatomical, physiological, behavioral, and sociocultural), and their implications and interactions. We propose a rationale where both perspectives coexist, where diversity is the default, establishing a delimitation to the conflation between sex and gender, while acknowledging their interaction. Whereas sex in humans and other mammals is a biological reality that is largely binary and based on genes, chromosomes, anatomy, and physiology, gender is a sociocultural construct that is often, but not always, concordant with a person' sex, and can span a multitude of expressions.

Exploring the physiological role of the G protein-coupled estrogen receptor (GPER) and its associations with human diseases

Estrogen is a group of hormones that collaborate with the nervous system to impact the overall well-being of all genders. It influences many processes, including those occurring in the central nervous system, affecting learning and memory, and playing roles in neurodegenerative diseases and mental disorders. The hormone's action is mediated by specific receptors. Significant roles of classical estrogen receptors, ERα and ERβ, in various diseases were known since many years, but after identifying a structurally and locationally distinct receptor, the G protein-coupled estrogen receptor (GPER), its role in human physiology and pathophysiology was investigated. This review compiles GPER-related information, highlighting its impact on homeostasis and diseases, while putting special attention on functions and dysfunctions of this receptor in neurobiology and biobehavioral processes. Understanding the receptor modulation possibilities is essential for therapy, as disruptions in receptors can lead to diseases or disorders, irrespective of correct estrogen levels. We conclude that studies on the GPER receptor have the potential to develop therapies that regulate estrogen and positively impact human health.

Prenatal Exposure to Bisphenol A and/or Diethylhexyl Phthalate Impacts Brain Monoamine Levels in Rat Offspring

This study examines the sex-specific effects of gestational exposure (days 6-21) to endocrine-disrupting chemicals such as bisphenol A (BPA), diethylhexyl phthalate (DEHP), or their combination on brain monoamine levels that play an important role in regulating behavior. Pregnant Sprague-Dawley rats were orally administered saline, low doses (5 µg/kg BW/day) of BPA or DEHP, and their combination or a high dose (7.5 mg/kg BW/day) of DEHP alone or in combination with BPA during pregnancy. The offspring were subjected to a behavioral test and sacrificed in adulthood, and the brains were analyzed for neurotransmitter levels. In the paraventricular nucleus, there was a marked reduction in dopamine levels (p < 0.01) in male offspring from the BPA, DEHP, and B + D (HD) groups, which correlated well with their shock probe defensive burying times. Neurotransmitter changes in all brain regions examined were significant in female offspring, with DEHP (HD) females being affected the most, followed by the B + D groups. BPA and/or DEHP (LD) increased monoamine turnover in a region-specific manner in male offspring (p < 0.05). Overall, prenatal exposure to BPA, DEHP, or their combination alters monoamine levels in a brain region-specific, sex-specific, and dose-dependent manner, which could have implications for their behavioral and neuroendocrine effects.

Androgen effects on mesoprefrontal dopamine systems in the adult male brain

Epidemiological data show that males are more often and/or more severely affected by symptoms of prefrontal cortical dysfunction in schizophrenia, Parkinson's disease and other disorders in which dopamine circuits associated with the prefrontal cortex are dysregulated. This review focuses on research showing that these dopamine circuits are powerfully regulated by androgens. It begins with a brief overview of the sex differences that distinguish prefrontal function in health and prefrontal dysfunction or decline in aging and/or neuropsychiatric disease. This review article then spotlights data from human subjects and animal models that specifically identify androgens as potent modulators of prefrontal cortical operations and of closely related, functionally critical measures of prefrontal dopamine level or tone. Candidate mechanisms by which androgens dynamically control mesoprefrontal dopamine systems and impact prefrontal states of hypo- and hyper-dopaminergia in aging and disease are then considered. This is followed by discussion of a working model that identifies a key locus for androgen modulation of mesoprefrontal dopamine systems as residing within the prefrontal cortex itself. The last sections of this review critically consider the ways in which the organization and regulation of mesoprefrontal dopamine circuits differ in the adult male and female brain, and highlights gaps where more research is needed.

Prenatal exposure to multiple environmental chemicals and birth size

BACKGROUND

Epidemiological studies addressing the combined effects of exposure to chemical mixtures at different stages of pregnancy on birth size are scarce.

OBJECTIVE

To evaluate the association between prenatal exposure to chemical mixtures and birth size.

METHODS

Our previous study repeatedly measured the urinary concentrations of 34 chemical substances among 743 pregnant women and identified three distinct clusters of exposed population and six dominant principal components of exposed chemicals in each trimester. In this study, we assessed the associations of these exposure profiles with birth weight, birth length, and ponderal index using multivariable linear regression.

RESULTS

We found that compared with women in cluster 1 (lower urinary chemical concentrations), women in cluster 2 (higher urinary concentrations of metals, benzothiazole, benzotriazole, and some phenols), and women in cluster 3 (higher urinary concentrations of phthalates) were more likely to give birth to children with higher birth length [0.23 cm (95% CI: -0.03, 0.49); 0.29 cm (95%CI: 0.03, 0.54), respectively]. This association was observed only in 1st trimester. In addition, prenatal exposure to PC3 (higher benzophenones loading) was associated with reduced birth length across pregnancy [-0.07 cm (95% CI: -0.18, 0.03) in 1st and 2nd trimester; -0.13 cm (95% CI: -0.24, -0.03) in 3rd trimester]. Exposure to PC6 (higher thallium and BPA loading in 2nd trimester) was associated with increased birth length [0.15 cm (95% CI: 0.05, 0.26)]. Compared with other outcomes, associations of both clusters and PCs with birth length were stronger, and these associations were more pronounced in boys.

IMPACT STATEMENT

Exposure to multiple chemicals simultaneously, the actual exposure situation of pregnant women, was associated with birth size, indicating that chemical mixtures should be taken more seriously when studying the health effects of pollutants.

The role of autophagy in Parkinson's disease: a gender difference overview

Recent studies have demonstrated dysregulation of the autophagy pathway in patients with Parkinson's disease (PD) and in animal models of PD, highlighting its emerging role in disease. In particular, several studies indicate that autophagy, which is an essential degradative process for the damaged protein homeostasis and the management of cell balance, can manifest significant variations according to gender. While some evidence suggests increased autophagic activation in men with PD, women may have distinct regulatory patterns. In this review, we examined the existing literature on gender differences in PD-associated autophagic processes, focusing on the autophagy related proteins (ATGs) and leucine rich repeat kinase 2 (LRRK2) genes. Also, this review would suggest that an in-depth understanding of these gender differences in autophagic processes could open new perspectives for personalized therapeutic strategies, promoting more effective and targeted management of PD.

Chronic Caffeine Consumption, Alone or Combined with Agomelatine or Quetiapine, Reduces the Maximum EEG Peak, As Linked to Cortical Neurodegeneration, Ovarian Estrogen Receptor Alpha, and Melatonin Receptor 2

RATIONALE

Evidence of the effects of chronic caffeine (CAFF)-containing beverages, alone or in combination with agomelatine (AGO) or quetiapine (QUET), on electroencephalography (EEG), which is relevant to cognition, epileptogenesis, and ovarian function, remains lacking. Estrogenic, adenosinergic, and melatonergic signaling is possibly linked to the dynamics of these substances.

OBJECTIVES

The brain and ovarian effects of CAFF were compared with those of AGO + CAFF and QUET + CAFF. The implications of estrogenic, adenosinergic, and melatonergic signaling and the brain-ovarian crosstalk were investigated.

METHODS

Adult female rats were administered AGO (10 mg/kg), QUET (10 mg/kg), CAFF, AGO + CAFF, or QUET + CAFF, once daily for 8 weeks. EEG, estrous cycle progression, and microstructure of the brain and ovaries were examined. Brain and ovarian 17β-estradiol (E2), antimullerian hormone (AMH), estrogen receptor alpha (E2Rα), adenosine receptor 2A (A2AR), and melatonin receptor 2 (MT2R) were assessed.

RESULTS

CAFF, alone or combined with AGO or QUET, reduced the maximum EEG peak, which was positively linked to ovarian E2Rα, negatively correlated to cortical neurodegeneration and ovarian MT2R, and associated with cystic ovaries. A large corpus luteum emerged with AGO + CAFF and QUET + CAFF, antagonizing the CAFF-mediated increased ovarian A2AR and reduced cortical E2Rα. AGO + CAFF provoked TTP delay and increased ovarian AMH, while QUET + CAFF slowed source EEG frequency to δ range and increased brain E2.

CONCLUSIONS

CAFF treatment triggered brain and ovarian derangements partially antagonized with concurrent AGO or QUET administration but with no overt affection of estrus cycle progression. Estrogenic, adenosinergic, and melatonergic signaling and brain-ovarian crosstalk may explain these effects.

Sex differences in the relationship between depression and Alzheimer's disease-mechanisms, genetics, and therapeutic opportunities

Depression and Alzheimer's disease (AD) are prevalent neuropsychiatric disorders with intriguing epidemiological overlaps. Their interrelation has recently garnered widespread attention. Empirical evidence indicates that depressive disorders significantly contribute to AD risk, and approximately a quarter of AD patients have comorbid major depressive disorder, which underscores the bidirectional link between AD and depression. A growing body of evidence substantiates pervasive sex differences in both AD and depression: both conditions exhibit a higher incidence among women than among men. However, the available literature on this topic is somewhat fragmented, with no comprehensive review that delineates sex disparities in the depression-AD correlation. In this review, we bridge these gaps by summarizing recent progress in understanding sex-based differences in mechanisms, genetics, and therapeutic prospects for depression and AD. Additionally, we outline key challenges in the field, holding potential for improving treatment precision and efficacy tailored to male and female patients' distinct needs.

Identification and characterisation of a novel interaction between oestrogen receptor alpha and FOXP2

Forkhead box P2 (FOXP2) regulates expression of various genes and is associated with language, speech and neural development as well as cancer. Since there may be a putative link between sex and language and because transcription factors rarely function in isolation, this study aims to investigate whether FOXP2 directly associates with oestrogen receptor α (ER1), a nuclear receptor responsible for sexual differentiation that is also associated with cancer. Isothermal titration calorimetry and fluorescence anisotropy were used to investigate the interaction between the DNA-binding forkhead domain (FHD) of FOXP2, the N-terminal region (NT) of FOXP2, and the ligand-binding domain (LBD) of ER1. ER1 LBD does not interact with FOXP2 NT but associates with apo-FOXP2 FHD in an enthalpically favourable manner. The affinity of this interaction is inversely correlated to the salt concentration. Additionally, FOXP2 FHD that is bound to ER1 LBD, has reduced ability to interact with its cognate DNA. This research identifies a novel interaction between ER1 LBD and FOXP2 FHD and shows that the interaction is regulated by salt. Moreover, FOXP2 FHD cannot bind to both ER1 LBD and DNA simultaneously, suggesting that this interaction could be involved in regulating the transcriptional pathway of FOXP2 should the interaction be found in vivo. This study could serve as a foundation for uncovering the basis of sexual dimorphism in speech and language development and related disorders and potentially offers an alternate for targeted cancer therapies.

Differential binding of CREB and REST/NRSF to NMDAR1 promoter is associated with the sex-selective cognitive deficit following postnatal PBDE-209 exposure in mice

Neonatal exposure to decabromodiphenyl ether (PBDE-209), a widely used flame retardant, affects cognitive performances in the later stage of life in a sex-dependent manner. PBDE-209 interferes with glutamatergic signaling and N-methyl-D-aspartate receptor (NMDAR) subunits with unresolved regulatory mechanisms. This study exposed male and female mice pups through postnatal day (PND) 3-10 to PBDE-209 (oral dose: 0, 6, or 20 mg/kg body weight). The frontal cortex and hippocampus, collected from neonate (PND 11) and young (PND 60) mice, were analyzed for cAMP response element-binding protein (CREB) and RE1-silencing transcription factor/ Neuron-restrictive silencer factor (REST/NRSF) binding to NMDAR1 promoter and expression of NMDAR1 gene by electrophoretic mobility shift assay and semi-quantitative RT-PCR respectively. Behavioral changes were assessed using spontaneous alternation behavior and novel object recognition tests in young mice. In neonates, the binding of CREB was increased, while REST/NRSF was decreased significantly to their cognate NMDAR1 promoter sequences at the high dose of PBDE-209 in both the sexes. This reciprocal pattern of CREB and REST/NRSF interactions correlates with the up-regulation of NMDAR1 expression. Young males followed a similar pattern of CREB and REST/NRSF binding and NMDAR1 expression as in neonates. Surprisingly, young females did not show any alteration when compared to age-matched controls. Also, we found that only young males showed working and recognition memory deficits. These results indicate that early exposure to PBDE-209 interferes with CREB- and REST/NRSF-dependent regulation of the NMDAR1 gene in an acute setting. However, long-term effects persist only in young males that could be associated with cognitive impairment.

What do measures of gender identity tell us about gender identity over time?

Gender identity is a multifaceted concept and is represented by a wide range of measures and constructs including both self-report and researcher observations of preferences and behaviours. However, despite their similar theoretical underpinning, gender identity measures are rarely found to correlate with one another, and contrasting patterns and trajectories are often found for each construct (Egan & Perry, Developmental Psychology, 37, 2001, 451). Therefore, this systematic review aimed to present a review of the longitudinal research evidence surrounding gender identity development in the absence of formal intervention. Using a systematic search strategy, 21 studies were identified. Narrative synthesis was used to synthesize the data collected in these studies and trajectories were explored for (1) self-identification measures of gender identity, (2) clothing preferences, (3) peer preferences, and (4) object/activity preferences. Overall, the results of this systematic review are consistent with wider research suggesting that distinct developmental patterns can be observed when using different constructs and measures of gender identity.

Sex differences in adverse events in Medicare individuals ≥ 66 years of age post glioblastoma treatment

PURPOSE

Glioblastoma (GB) is the most common primary malignant brain tumor with the highest incidence occurring in older adults with a median age at diagnosis of 64 years old. While treatment often improves survival it brings toxicities and adverse events (AE). Here we identify sex differences in treatment patterns and AE in individuals ≥ 66 years at diagnosis with GB.

METHODS

Using the SEER-Medicare dataset sex differences in adverse events were assessed using multivariable logistic regression performed to calculate the male/female odds ratio (M/F OR) and 95% confidence intervals [95% CI] of experiencing an AE adjusted for demographic variables and Elixhauser comorbidity score.

RESULTS

Males with GB were more likely to receive standard of care (SOC; Surgery with concurrent radio-chemotherapy) [20%] compared to females [17%], whereas females were more likely to receive no treatment [26%] compared to males [21%]. Females with GB receiving SOC were more likely to develop gastrointestinal disorders (M/F OR = 0.76; 95% CI,0.64-0.91, p = 0.002) or blood and lymphatic system disorders (M/F OR = 0.79; 95% CI,0.66-0.95, p = 0.012). Males with GB receiving SOC were more likely to develop cardiac disorders (M/F OR = 1.21; 95% CI,1.02-1.44, p = 0.029) and renal disorders (M/F OR = 1.65; 95% CI,1.37-2.01, p < 0.001).

CONCLUSIONS

Sex differences for individuals, 66 years and older, diagnosed with GB exist in treatment received and adverse events developed across different treatment modalities.

Effects of estrogen on spatial navigation and memory

RATIONALE

Animal studies suggest that the so-called "female" hormone estrogen enhances spatial navigation and memory. This contradicts the observation that males generally out-perform females in spatial navigation and tasks involving spatial memory. A closer look at the vast number of studies actually reveals that performance differences are not so clear.

OBJECTIVES

To help clarify the unclear performance differences between men and women and the role of estrogen, we attempted to isolate organizational from activational effects of estrogen on spatial navigation and memory.

METHODS

In a double-blind, placebo-controlled study, we tested the effects of orally administered estradiol valerate (E2V) in healthy, young women in their low-hormone menstrual cycle phase, compared to healthy, young men. Participants performed several first-person, environmentally rich, 3-D computer games inspired by spatial navigation and memory paradigms in animal research.

RESULTS

We found navigation behavior suggesting that sex effects dominated any E2 effects with men performing better with allocentric strategies and women with egocentric strategies. Increased E2 levels did not lead to general improvements in spatial ability in either sex but to behavioral changes reflecting navigation flexibility.

CONCLUSION

Estrogen-driven differences in spatial cognition might be better characterized on a spectrum of navigation flexibility rather than by categorical performance measures or skills.

Estrogen receptor GPR30 in the anterior cingulate cortex mediates exacerbated neuropathic pain in ovariectomized mice

Menopausal women experience neuropathic pain 63% more frequently than men do, which may attribute to the estrogen withdrawal. However, the underlying mechanisms remain unclear. Here, the role of estrogen receptors (ERs) in ovariectomized (OVX) female mice following chronic constriction injury (CCI) was investigated. With 17β-estradiol (E2) supplemented, aggravated mechanical allodynia in OVX mice could be significantly alleviated, particularly after intra-anterior cingulate cortex (ACC) E2 delivery. Pharmacological interventions further demonstrated that the agonist of G-protein-coupled estrogen receptor 30 (GPR30), rather than ERα or ERβ in the ACC, exhibited the similar analgesic effect as E2, whereas antagonist of GPR30 exacerbated allodynia. Furthermore, OVX surgery reduced GPR30 expression in the ACC, which could be restored with estrogen supplementation. Selective downregulation of GPR30 in the ACC of naïve female mice induces mechanical allodynia, whereas GPR30 overexpression in the ACC remarkedly alleviated OVX-exacerbated allodynia. Collectively, estrogen withdrawal could downregulate the ACC GPR30 expression, resulting in exacerbated neuropathic pain. Our findings highlight the importance of GPR30 in the ACC in aggravated neuropathic pain during menopause, and offer a potential therapeutic candidate for neuropathic pain management in menopausal women.

Endocrine Disruptors and Metabolic Changes: Impact on Puberty Control

OBJECTIVE

This study aims to explore the significant impact of environmental chemicals on disease development, focusing on their role in developing metabolic and endocrine diseases. The objective is to understand how these chemicals contribute to the increasing prevalence of precocious puberty, considering various factors, including epigenetic changes, lifestyle, and emotional disturbances.

METHODS

The study employs a comprehensive review of descriptive observational studies in both human and animal models to identify a degree of causality between exposure to environmental chemicals and disease development, specifically focusing on endocrine disruption. Due to ethical constraints, direct causation studies in human subjects are not feasible; therefore, the research relies on accumulated observational data.

RESULTS

Puberty is a crucial life period with marked physiological and psychological changes. The age at which sexual characteristics develop is changing in many regions. The findings indicate a correlation between exposure to endocrine-disrupting chemicals and the early onset of puberty. These chemicals have been shown to interfere with normal hormonal processes, particularly during critical developmental stages such as adolescence. The research also highlights the interaction of these chemical exposures with other factors, including nutritional history, social and lifestyle changes, and emotional stress, which together contribute to the prevalence of precocious puberty.

CONCLUSION

Environmental chemicals significantly contribute to the development of certain metabolic and endocrine diseases, particularly in the rising incidence of precocious puberty. Although the evidence is mainly observational, it adequately justifies regulatory actions to reduce exposure risks. Furthermore, these findings highlight the urgent need for more research on the epigenetic effects of these chemicals and their wider impact on human health, especially during vital developmental periods.

The impact of estradiol on serotonin, glutamate, and dopamine systems

Estradiol, the most potent and prevalent member of the estrogen class of steroid hormones and is expressed in both sexes. Functioning as a neuroactive steroid, it plays a crucial role in modulating neurotransmitter systems affecting neuronal circuits and brain functions including learning and memory, reward and sexual behaviors. These neurotransmitter systems encompass the serotonergic, dopaminergic, and glutamatergic signaling pathways. Consequently, this review examines the pivotal role of estradiol and its receptors in the regulation of these neurotransmitter systems in the brain. Through a comprehensive analysis of current literature, we investigate the multifaceted effects of estradiol on key neurotransmitter signaling systems, namely serotonin, dopamine, and glutamate. Findings from rodent models illuminate the impact of hormone manipulations, such as gonadectomy, on the regulation of neuronal brain circuits, providing valuable insights into the connection between hormonal fluctuations and neurotransmitter regulation. Estradiol exerts its effects by binding to three estrogen receptors: estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), and G protein-coupled receptor (GPER). Thus, this review explores the promising outcomes observed with estradiol and estrogen receptor agonists administration in both gonadectomized and/or genetically knockout rodents, suggesting potential therapeutic avenues. Despite limited human studies on this topic, the findings underscore the significance of translational research in bridging the gap between preclinical findings and clinical applications. This approach offers valuable insights into the complex relationship between estradiol and neurotransmitter systems. The integration of evidence from neurotransmitter systems and receptor-specific effects not only enhances our understanding of the neurobiological basis of physiological brain functioning but also provides a comprehensive framework for the understanding of possible pathophysiological mechanisms resulting to disease states. By unraveling the complexities of estradiol's impact on neurotransmitter regulation, this review contributes to advancing the field and lays the groundwork for future research aimed at refining understanding of the relationship between estradiol and neuronal circuits as well as their involvement in brain disorders.

Excess neonatal testosterone causes male-specific social and fear memory deficits in wild-type mice

Neurodevelopmental disorders (ND) disproportionately affect males compared to females, and Autism Spectrum Disorder (ASD) in particular exhibits a 4:1 male bias. The biological mechanisms of this female protection or male susceptibility have not been identified. There is some evidence to suggest that fetal/neonatal gonadal hormones, which play pivotal roles in many aspects of development, may contribute. Here, we investigate the role of testosterone administration during a critical period of development, and its effects on social approach and fear learning in C57BL/6J wildtype mice. Male, but not female mice treated with testosterone on the day of birth (PN0) exhibited deficits in both social behavior and contextual fear conditioning, whereas mice treated with the same dose of testosterone on postnatal day 18 (PN18) did not display such impairments. Testosterone administration did not induce anxiogenic effects or lead to changes in body weight compared to the vehicle-treated group. These impairmeants are relevant to ND and may help identify novel treatment targets.

Clinical impacts of n-3 fatty acids supplementation on depression symptoms: an umbrella review of meta-analyses

Several meta-analyses investigating the efficacy of n-3 PUFA in alleviating depression symptoms have reported conflicting findings. In the present study, we aimed to perform an umbrella meta-analysis to provide a definite conclusion. A comprehensive systematic search of PubMed, Scopus, Embase, Web of Science and Cochrane Central Library was performed up to June 2021. Meta-analysis studies evaluating the effects of n-3 PUFA on depression symptoms were included. The quality of the included meta-analyses was assessed using AMSTAR questionnaire. Out of 101 studies, twenty-two studies with twenty-six effect sizes (ES) were eligible for inclusion. Sixteen ES showed significant improving effect of n-3 supplementation on depression symptoms among which eleven ES had small ES. The other studies observed no significant effect. Available evidence suggests that n-3 PUFA (EPA, DHA) supplementation could be considered as an effective add-on therapeutic approach in relieving depression symptoms.

Progesterone Levels in Adolescent Female Athletes May Contribute to Decreased Cognitive Performance During Acute Phase of Sports-Related Concussion

Although many outcome studies pertaining to sports-related concussion exist, female athletes with concussion remain an understudied group. We examined whether neurocognitive performance in adolescent females with sports-related concussion (SRC) is related to menstrual cycle-related hormone levels measured at one-week post-concussion, one-month post-concussion, or both. Thirty-eight female athletes, ages 14-18, were matched into two groups: SRC or healthy control. Self-reported symptom scores were higher among concussed females in the luteal phase, when progesterone levels are highest. Results suggest that progesterone levels may contribute to a heightened experience of symptoms during the acute phase of SRC, providing further evidence of a possible link between progesterone and symptom scores following concussion.

Comparative Transcriptomics Data Profiling Reveals E2F Targets as an Important Biological Pathway Overexpressed in Intellectual Disability Disorder

Intellectual disability (ID) is an early childhood neurodevelopmental disorder that is characterized by impaired intellectual functioning and adaptive behavior. It is one of the major concerns in the field of neurodevelopmental disorders across the globe. Diversified approaches have been put forward to overcome this problem. Among all these approaches, high throughput transcriptomic analysis has taken an important dimension. The identification of genes causing ID rapidly increased over the past 3 to 5 years owing to the use of sophisticated high throughput sequencing platforms. Early monitoring and preventions are much important for such disorder as their progression occurs during fetal development. This study is an attempt to identify differentially expressed genes (DEGs) and upregulated biological processes involved in development of ID patients through comparative analysis of available transcriptomics data. A total of 7 transcriptomic studies were retrieved from National Center for Biotechnology Information (NCBI) and were subjected to quality check and trimming prior to alignment. The normalization and differential expression analysis were carried out using DESeq2 and EdgeR packages of Rstudio to identify DEGs in ID. In progression of the study, functional enrichment analysis of the results obtained from both DESeq2 and EdgeR was done using gene set enrichment analysis (GSEA) tool to identify major upregulated biological processes involved in ID. Our findings concluded that monitoring the level of E2F targets, estrogen, and genes related to oxidative phosphorylation, DNA repair, and glycolysis during the developmental stage of an individual can help in the early detection of ID disorder.

Prevalence and correlates of depressive symptoms among matriculated university students in Singapore during Covid-19 pandemic: findings from a repeated cross-sectional analysis

BACKGROUND

Depression is a common issue among university students and has been particularly exacerbated during the COVID-19 pandemic. However, limited research has specifically focused on depression among university entrants.

OBJECTIVES

This study aimed to determine the prevalence of depression severity and identify associated factors during different phases of the COVID-19 pandemic using health screening questionnaires completed by matriculated university students in Singapore.

METHODS

A repeated cross-sectional study was conducted at a public university in Singapore. Data from health screening questionnaires administered in 2020 and 2021, involving 15,630 newly enrolled university students, were analyzed. The questionnaires covered students' sociodemographic information, physical health status, own and family medical history, lifestyle behaviours, and the Patient Health Questionnaire (PHQ-9). The PHQ-9 was used to measure the severity of depressive symptoms, categorizing into moderate to severe depressive symptoms (MSDS), mild depressive symptoms (MDS), or no depressive symptom (NDS). Multinomial logistic regression was used to assess the sociodemographic, physical and behavioural correlates of depression.

RESULTS

The prevalence of MSDS was 1% in both 2020 and 2021, while the rates for MDS were 1.93% in 2020 and 1.64% in 2021. In the 2020 cohort, male freshmen who reported better health had a lower likelihood of experiencing depression. Conversely, students of Malay ethnicity, those majoring in Engineering, those with multiple chronic diseases, monthly alcohol consumers, current smokers, and those with a family history of mental disorder had a higher likelihood of experiencing depression. Moreover, students who lived on-campus in the 2021 cohort were less likely to experience depression than those living off-campus. However, the associations between academic majors, alcohol consumption, and smoking with depression were not significant in the 2021 cohort.

CONCLUSIONS

This study reported a low prevalence of both MSDS and MDS among university entrants in Singapore. The study further identified three categories of factors associated with depression: sociodemographic, physical, and behavioural. This study suggests policy interventions to enhance targeted social support that address each student group's specific requirements and susceptibilities. A more extensive and comprehensive study is warranted to assess the changes in student mental health status post-COVID-19 pandemic.

Depression in Women: Potential Biological and Sociocultural Factors Driving the Sex Effect

Important sex-related differences have been observed in the onset, prevalence, and clinical phenotype of depression, based on several epidemiological studies. Social, behavioural, and educational factors have a great role in underlying this bias; however, also several biological factors are extensively involved. Indeed, sexually dimorphic biological systems might represent the underlying ground for these disparities, including cerebral structures and neural correlates, reproductive hormones, stress response pathways, the immune system and inflammatory reaction, metabolism, and fat distribution. Furthermore, in this perspective, it is also important to consider and focus the attention on specific ages and life stages of individuals: indeed, women experience during their life specific periods of reproductive transitional phases, which are not found in men, that represent windows of particular psychological vulnerability. In addition to these, other biologically related risk factors, including the occurrence of sleep disturbances and the exposure to childhood trauma, which are found to differentially affect men and women, are also putative underlying mechanisms of the clinical bias of depression. Overall, by taking into account major differences which characterize men and women it might be possible to improve the diagnostic process, as well as treat more efficiently depressed individuals, based on a more personalized medicine and research.

Chronic Variable Stress and Cafeteria Diet Combination Exacerbate Microglia and c-fos Activation but Not Experimental Anxiety or Depression in a Menopause Model

The menopause transition is a vulnerable period for developing both psychiatric and metabolic disorders, and both can be enhanced by stressful events worsening their effects. The present study aimed to evaluate whether a cafeteria diet (CAF) combined with chronic variable stress (CVS) exacerbates anxious- or depressive-like behavior and neuronal activation, cell proliferation and survival, and microglia activation in middle-aged ovariectomized (OVX) rats. In addition, body weight, lipid profile, insulin resistance, and corticosterone as an index of metabolic changes or hypothalamus-pituitary-adrenal (HPA) axis activation, and the serum pro-inflammatory cytokines IL-6, IL-β, and TNFα were measured. A CAF diet increased body weight, lipid profile, and insulin resistance. CVS increased corticosterone and reduced HDL. A CAF produced anxiety-like behaviors, whereas CVS induced depressive-like behaviors. CVS increased serum TNFα independently of diet. A CAF and CVS separately enhanced the percentage of Iba-positive cells in the hippocampus; the combination of factors further increased Iba-positive cells in the ventral hippocampus. A CAF and CVS increased the c-fos-positive cells in the hippocampus; the combination of factors increased the number of positive cells expressing c-fos in the ventral hippocampus even more. The combination of a CAF and CVS generates a slight neuroinflammation process and neuronal activation in a hippocampal region-specific manner and differentially affects the behavior.

Gender gap in deep brain stimulation for Parkinson's disease: preliminary results of a retrospective study

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment of PD for both women and men. However, discussions have been reported about the impact of STN-DBS surgery in PD. The aim of our study is to identify differences between men and women in terms of pre- and post-DBS symptoms and try to explain the possible causes. In the current study, we evaluated the gender impact on STN-DBS in PD at the Department of Neurosurgery of University of Naples "Federico II" from 2013 to 2021. Motor and non-motor symptoms were evaluated. To compare the data before and after surgery and between the genders, Wilcoxon-Mann-Whitney tests were performed. A total of 43 patients with PD were included; of them, 17 (39%) were female. Baseline evaluation revealed no gender differences in the age of onset (p = 0.87). Not significant differences were noted in the Unified Parkinson's Disease Rating Scale (UPDRS) pre-surgery score, but if we consider UPDRS subscores of motor examination, significant clinical improvement was reported in both male and female in terms of UPDRS pre- and post-surgery (p < 0.001). STN-DBS is a highly effective treatment for motor and non-motor symptoms of PD for both women and men but our study hints towards gender-specific outcomes in motor domains. Improving our knowledge in this field can allow us to implement strategies to identify new directions in the development of an adequate treatment of PD in terms of surgical intervention and in consideration of the gender.

Prevalence of anxiety and depression among Lebanese women using oral contraceptives: a cross-sectional study

BACKGROUND

Oral contraceptives (OCs) are used worldwide, including Lebanese women. However, the association between OCs use and anxiety or depression remains unclear. This study aims to assess the prevalence of anxiety and depression among Lebanese women using oral contraceptive pills and investigate the differential impact of combined oral contraceptives (COCs) versus progestogen-only pills (POPs) on mental health outcomes.

METHODS

A cross-sectional study was conducted among a sample of Lebanese women using OCs between January and March 2023. Nine hundred nighty seven out of the 2051 women who took part in the survey met our criteria and were included in this study. Data on anxiety and depression were collected using validated and reliable scales, the Arabic versions of the Generalized Anxiety Disorder-7 Questionnaire (GAD-7) and the Patient Health Questionnaire-9 (PHQ-9). Statistical analyses, including multivariate analysis, were performed to assess the association between OCs type (COC vs. POP) and anxiety/depression.

RESULTS

The prevalence of anxiety and depression among Lebanese women taking OCs was found to be 39.9% and 64.3%, respectively. Furthermore, the study revealed that POP users had 2.8 times higher odds of developing anxiety (adjusted odds ratio ORadj = 2.8 with 95% confidence interval CI of 1.770 to 4.435) p-value < 0.001 and 9.2 times higher odds of developing depression (adjusted odds ratio ORadj = 9.2 with 95% confidence interval CI of 5.790 to 14.506) p-value < 0.001 compared to COC users.

CONCLUSION

The results of this study shed light on the elevated prevalence of anxiety and depression among Lebanese women using OCs and emphasized the varying effects of COCs and POPs on their mental health outcomes. Further research is needed to comprehensively understand this association, considering both the dosage and specific type of oral contraceptive to improve the overall well-being of women using these contraceptives.

The impact of 17β-estradiol on the estrogen-deficient female brain: from mechanisms to therapy with hot flushes as target symptoms

Sex steroids are essential for whole body development and functions. Among these steroids, 17β-estradiol (E2) has been known as the principal "female" hormone. However, E2's actions are not restricted to reproduction, as it plays a myriad of important roles throughout the body including the brain. In fact, this hormone also has profound effects on the female brain throughout the life span. The brain receives this gonadal hormone from the circulation, and local formation of E2 from testosterone via aromatase has been shown. Therefore, the brain appears to be not only a target but also a producer of this steroid. The beneficial broad actions of the hormone in the brain are the end result of well-orchestrated delayed genomic and rapid non-genomic responses. A drastic and steady decline in circulating E2 in a female occurs naturally over an extended period of time starting with the perimenopausal transition, as ovarian functions are gradually declining until the complete cessation of the menstrual cycle. The waning of endogenous E2 in the blood leads to an estrogen-deficient brain. This adversely impacts neural and behavioral functions and may lead to a constellation of maladies such as vasomotor symptoms with varying severity among women and, also, over time within an individual. Vasomotor symptoms triggered apparently by estrogen deficiency are related to abnormal changes in the hypothalamus particularly involving its preoptic and anterior areas. However, conventional hormone therapies to "re-estrogenize" the brain carry risks due to multiple confounding factors including unwanted hormonal exposure of the periphery. In this review, we focus on hot flushes as the archetypic manifestation of estrogen deprivation in the brain. Beyond our current mechanistic understanding of the symptoms, we highlight the arduous process and various obstacles of developing effective and safe therapies for hot flushes using E2. We discuss our preclinical efforts to constrain E2's beneficial actions to the brain by the DHED prodrug our laboratory developed to treat maladies associated with the hypoestrogenic brain.

Developmental and adult stress: effects of steroids and neurosteroids

In humans, exposure to early life adversity has profound implications for susceptibility to developing neuropsychiatric disorders later in life. Studies in rodents have shown that stress experienced during early postnatal life can have lasting effects on brain development. Glucocorticoids and sex steroids are produced in endocrine glands and the brain from cholesterol; these molecules bind to nuclear and membrane-associated steroid receptors. Unlike other steroids that can also be made in the brain, neurosteroids bind specifically to neurotransmitter receptors, not steroid receptors. The relationships among steroids, neurosteroids, and stress are multifaceted and not yet fully understood. However, studies demonstrating altered levels of progestogens, androgens, estrogens, glucocorticoids, and their neuroactive metabolites in both developmental and adult stress paradigms strongly suggest that these molecules may be important players in stress effects on brain circuits and behavior. In this review, we discuss the influence of developmental and adult stress on various components of the brain, including neurons, glia, and perineuronal nets, with a focus on sex steroids and neurosteroids. Gaining an enhanced understanding of how early adversity impacts the intricate systems of brain steroid and neurosteroid regulation could prove instrumental in identifying novel therapeutic targets for stress-related conditions.

Transition to a market economy and chronic psychosocial stress in northern Laos: An exploratory study of urinary free cortisol in rural residents

OBJECTIVES

The indigenous population in northern Laos has experienced a transition from self-sufficiency to a market-oriented economy, which may have brought about unprecedented chronic psychosocial stress. This study examined the association between the transition to a market economy and urinary free cortisol (UFC) concentration as a stress biomarker among rural residents of three villages with different degrees of integration into the market economy.

METHODS

An interview survey and urine sample collection were conducted in August 2018 and March 2019. We measured the UFC concentration in spot urine samples collected in the morning from participants aged 20-60 years (n = 168) using an enzyme-linked immunosorbent assay. Multiple linear regression analysis was performed to examine differences in UFC concentrations among villages by sex, with time of arrival for the survey, age, and body mass index included as covariates.

RESULTS

The UFC concentration was higher in men living in the village with the highest degree of integration into the market economy than in those in the two villages with a lower dependence on cash, possibly linking increased stress levels with a change in employment type. This trend was not observed in women.

CONCLUSION

Socioeconomic changes incidental to a transition to a market economy may increase the stress levels of men in northern Laos.

Sex Differences in Stress Response: Classical Mechanisms and Beyond

Neuropsychiatric disorders, which are associated with stress hormone dysregulation, occur at different rates in men and women. Moreover, nowadays, preclinical and clinical evidence demonstrates that sex and gender can lead to differences in stress responses that predispose males and females to different expressions of similar pathologies. In this curated review, we focus on what is known about sex differences in classic mechanisms of stress response, such as glucocorticoid hormones and corticotrophin-releasing factor (CRF), which are components of the hypothalamicpituitary- adrenal (HPA) axis. Then, we present sex differences in neurotransmitter levels, such as serotonin, dopamine, glutamate and GABA, as well as indices of neurodegeneration, such as amyloid β and Tau. Gonadal hormone effects, such as estrogens and testosterone, are also discussed throughout the review. We also review in detail preclinical data investigating sex differences caused by recentlyrecognized regulators of stress and disease, such as the immune system, genetic and epigenetic mechanisms, as well neurosteroids. Finally, we discuss how understanding sex differences in stress responses, as well as in pharmacology, can be leveraged into novel, more efficacious therapeutics for all. Based on the supporting evidence, it is obvious that incorporating sex as a biological variable into preclinical research is imperative for the understanding and treatment of stress-related neuropsychiatric disorders, such as depression, anxiety and Alzheimer's disease.

Editors' Choice-Review-The Future of Carbon-Based Neurochemical Sensing: A Critical Perspective

Carbon-based sensors have remained critical materials for electrochemical detection of neurochemicals, rooted in their inherent biocompatibility and broad potential window. Real-time monitoring using fast-scan cyclic voltammetry has resulted in the rise of minimally invasive carbon fiber microelectrodes as the material of choice for making measurements in tissue, but challenges with carbon fiber's innate properties have limited its applicability to understudied neurochemicals. Here, we provide a critical review of the state of carbon-based real-time neurochemical detection and offer insight into ways we envision addressing these limitations in the future. This piece focuses on three main hinderances of traditional carbon fiber based materials: diminished temporal resolution due to geometric properties and adsorption/desorption properties of the material, poor selectivity/specificity to most neurochemicals, and the inability to tune amorphous carbon surfaces for specific interfacial interactions. Routes to addressing these challenges could lie in methods like computational modeling of single-molecule interfacial interactions, expansion to tunable carbon-based materials, and novel approaches to synthesizing these materials. We hope this critical piece does justice to describing the novel carbon-based materials that have preceded this work, and we hope this review provides useful solutions to innovate carbon-based material development in the future for individualized neurochemical structures.

Aromatase enzyme: Paving the way for exploring aromatization for cardio-renal protection

Documented male-female differences in the risk of cardiovascular and chronic kidney diseases have been largely attributed to estrogens. The cardiovascular and renal protective effects of estrogens are mediated via the activation of estrogen receptors (ERα and ERβ) and G protein-coupled estrogen receptor, and involve interactions with the renin-angiotensin-aldosterone system. Aromatase, also called estrogen synthase, is a cytochrome P-450 enzyme that plays a pivotal role in the conversion of androgens into estrogens. Estrogens are biosynthesized in gonadal and extra-gonadal sites by the action of aromatase. Evidence suggests that aromatase inhibitors, which are used to treat high estrogen-related pathologies, are associated with the development of cardiovascular events. We review the potential role of aromatization in providing cardio-renal protection and highlight several meta-analysis studies on cardiovascular events associated with aromatase inhibitors. Overall, we present the potential of aromatase enzyme as a fundamental contributor to cardio-renal protection.

Increased palmitoylation improves estrogen receptor alpha-dependent hippocampal synaptic deficits in a mouse model of synucleinopathy

Parkinson's disease (PD) is characterized by conversion of soluble α-synuclein (αS) into intraneuronal aggregates and degeneration of neurons and neuronal processes. Indications that women with early-stage PD display milder neurodegenerative features suggest that female sex partially protects against αS pathology. We previously reported that female sex and estradiol improved αS homeostasis and PD-like phenotypes in E46K-amplified (3K) αS mice. Here, we aimed to further dissect mechanisms that drive this sex dimorphism early in disease. We observed that synaptic abnormalities were delayed in females and improved by estradiol, mediated by local estrogen receptor alpha (ERα). Aberrant ERα distribution in 3K compared to wild-type mice was paired with its decreased palmitoylation. Treatment with ML348, a de-palmitoylation inhibitor, increased ERα availability and soluble αS homeostasis, ameliorating synaptic plasticity and cognitive and motor phenotypes. Our finding that sex differences in early-disease αS-induced synaptic impairment in 3KL mice are in part mediated by palmitoylated ERα may have functional and pathogenic implications for clinical PD.

Environmental exposure to paraben and its association with blood pressure: A cross-sectional study in China

Parabens (PBs) are the most widely used preservatives. Recent epidemiological studies have indicated that environmental exposure to parabens has adverse health effects, such as increased metabolic diseases risk. However, limited information is available on the cardiovascular effect of paraben exposure. Hence, we conducted a cross-sectional study investigating the associations between exposure to parabens with high blood pressure risk and blood pressure levels among the general Chinese population. In this study, we enrolled 1405 individuals from a medical center in Wuhan, China. Urinary methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP) and butylparaben (BuP) concentrations were determined. Multivariable logistic and linear regression models were applied to analyze the associations between urinary parabens and high blood pressure risk and blood pressure level changes. Bayesian kernel machine regression (BKMR) models were applied to estimate the combined effect of the four parabens. Compared with the first quartile group, participants with the fourth quartile of EtP, PrP, and ∑parabens (∑PBs) concentrations had a 2.10-fold (95% CI: 1.40, 3.00), 1.83-fold (95% CI: 1.27, 2.62) and 1.84-fold (95% CI: 1.27, 2.65) increased the risk of hypertension, respectively. High urinary EtP, PrP, and ∑PBs levels were found to increase the levels of systolic and diastolic blood pressure (SBP and DBP), mean arterial pressure (MAP), and mid-blood pressure (MBP). BKMR models indicated the overall effects of the paraben mixture were significantly associated with high blood pressure risk and blood pressure level changes. Furthermore, after stratification by sex, the associations of EtP exposure and blood pressure levels were more pronounced in males. Our results suggest that environmental exposure to parabens might elevate blood pressure levels and increase the risk of high blood pressure.

Male violence disrupts estrogen receptor β signaling in the female hippocampus

Women are the main target of intimate partner violence (IPV), which is escalating worldwide. Mechanisms subtending IPV-related disorders, such as anxiety, depression and PTSD, remain unclear. We employed a mouse model molded on an IPV scenario (male vs. female prolonged violent interaction) to unearth the neuroendocrine alterations triggered by an aggressive male mouse on the female murine brain. Experimental IPV (EIPV) prompted marked anxiety-like behavior in young female mice, coincident with high circulating/cerebral corticosterone levels. The hippocampus of EIPV-inflicted female animals displayed neuronal loss, reduced BrdU-DCX-positive nuclei, decreased mature DCX-positive cells, and diminished dendritic arborization level in the dentate gyrus (DG), features denoting impaired neurogenesis and neuronal differentiation. These hallmarks were associated with marked down-regulation of estrogen receptor β (ERβ) density in the hippocampus, especially in the DG and dependent prosurvival ERK signaling. Conversely, ERα expression was unchanged. After EIPV, the DG harbored lowered local BDNF pools, diminished TrkB phosphorylation, and elevated glucocorticoid receptor phosphorylation. In unison, ERβ KO mice had heightened anxiety-like behavior and curtailed BDNF levels at baseline, despite enhanced circulating estradiol levels, while dying prematurely during EIPV. Thus, reiterated male-to-female violence jeopardizes hippocampal homeostasis in the female brain, perturbing ERβ/BDNF signaling, thus instigating anxiety and chronic stress.

Peering into the Brain's Estrogen Receptors: PET Tracers for Visualization of Nuclear and Extranuclear Estrogen Receptors in Brain Disorders

Estrogen receptors (ERs) play a multitude of roles in brain function and are implicated in various brain disorders. The use of positron emission tomography (PET) tracers for the visualization of ERs' intricate landscape has shown promise in oncology but remains limited in the context of brain disorders. Despite recent progress in the identification and development of more selective ligands for various ERs subtypes, further optimization is necessary to enable the reliable and efficient imaging of these receptors. In this perspective, we briefly touch upon the significance of estrogen signaling in the brain and raise the setbacks associated with the development of PET tracers for identification of specific ERs subtypes in the brain. We then propose avenues for developing efficient PET tracers to non-invasively study the dynamics of ERs in the brain, as well as neuropsychiatric diseases associated with their malfunction in a longitudinal manner. This perspective puts several potential candidates on the table and highlights the unmet needs and areas requiring further research to unlock the full potential of PET tracers for ERs imaging, ultimately aiding in deepening our understanding of ERs and forging new avenues for potential therapeutic strategies.

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.

Chronic Stress That Changed Intestinal Permeability and Induced Inflammation Was Restored by Estrogen

Chronic psychological stress affects the health of humans and animals (especially females or pregnant bodies). In this study, a stress-induced model was established by placing eight-week-old female and pregnant mice in centrifuge tubes for 4 h to determine whether chronic stress affects the intestinal mucosal barrier and microbiota composition of pregnant mice. Compared with the control group, we found that norepinephrine (NE), corticosterone (CORT), and estradiol (E2) in plasma increased significantly in the stress group. We then observed a decreased down-regulation of anti-inflammatory cytokines and up-regulation of pro-inflammatory cytokines, which resulted in colonic mucosal injury, including a reduced number of goblet cells, proliferating cell nuclear antigen-positive cells, caspase-3, and expression of tight junction mRNA and protein. Moreover, the diversity and richness of the colonic microbiota decreased in pregnant mice. Bacteroidetes decreased, and pernicious bacteria were markedly increased. At last, we found E2 protects the intestinal epithelial cells after H2O2 treatment. Results suggested that 25 pg/mL E2 provides better protection for intestinal barrier after chronic stress, which greatly affected the intestinal mucosal barrier and altered the colonic microbiota composition.

Reproductive period duration and cognitive function in postmenopausal Latina women in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

OBJECTIVES

A shorter reproductive period, a marker of estrogen exposure, has been related to cognitive impairment among older (>65 years) non-Hispanic White women. We explored whether reproductive period duration, age at menarche, and age at menopause are related to cognitive function among postmenopausal Hispanic/Latina women.

METHODS

This cross-sectional analysis used baseline (Visit 1: 2008-2011) data from 3630 postmenopausal women in the Hispanic Community Health Study/Study of Latinos. Reproductive period duration, age at menarche, and age at menopause were assessed by self-report. Cognitive function variables included global cognition, verbal learning, memory, verbal fluency, and processing speed. Associations between each reproductive event and cognitive function were examined using multivariable linear and logistic regression analyses accounting for the complex survey design of the study and adjusting for socio-demographics, parity, and cardiovascular risk factors. We assessed whether associations differed by type of menopause (natural versus surgical) and hormone therapy use.

RESULTS

The study population was on average aged 59 years, with a mean reproductive period duration of 35 years. Older age at menopause and a longer reproductive period were related to higher verbal learning (β = 0.04, SE = 0.02; p < 0.05) and processing speed (ß = 0.16, SE = 0.04; p < 0.001); associations were more pronounced for women with natural menopause. Older age at menarche was associated with lower scores on the digit symbol substitution test (ß = -0.62, SE = 0.15; p < 0.0001). There were no associations with global cognition.

CONCLUSION

Among postmenopausal Hispanic/Latinas, a longer reproductive period was related to more favorable cognitive measures of verbal learning and processing speed. Our findings support the hypothesis that greater lifetime exposure to estrogens may be associated with higher cognitive performance.

Neuroprotective role for RORA in Parkinson's disease revealed by analysis of post-mortem brain and a dopaminergic cell line

Parkinson's disease (PD) is almost twice as prevalent in men, which has largely been attributed to neuroprotective effect of oestradiol in women. RORA (retinoic acid receptor-related orphan receptor alpha) regulates the transcription of central aromatase, the enzyme responsible for local oestradiol synthesis, simultaneously, RORA expression is regulated by sex hormones. Moreover, RORA protects neurones against oxidative stress, a key mechanism contributing to the loss of dopaminergic neurones in PD. Therefore, we hypothesized that there would be sex differences in RORA expression in the substantia nigra pars compacta (SNpc), which could contribute to sex differences observed in PD prevalence and pathogenesis. In a case control study, qPCR and western blot analyses were used to quantify gene and protein expression in the SNpc of post-mortem brains (n = 14 late-stage PD and 11 age and sex matched controls). The neuroprotective properties of a RORA agonist were then investigated directly using a cell culture toxin-based model of PD coupled with measures of viability, mitochondrial function and apoptosis. RORA was expressed at significantly higher levels in the SNpc from control females' brains compared to males. In PD, we found a significant increase in SNpc RORA expression in male PD compared to female PD. Treatment with a RORA agonist showed a significant neuroprotection in our cell culture model of PD and revealed significant effects on intracellular factors involved in neuronal survival and demise. This study is the first to demonstrate a sex specific pattern of RORA protein and gene expression in the SNpc of controls post-mortem human brains, and to show that this is differentially altered in male and female PD subjects, thus supporting a role for RORA in sex-specific aspects of PD. Furthermore, our in vitro PD model indicates mechanisms whereby a RORA agonist exerts its neuroprotective effect, thereby highlighting the translational potential for RORA ligands in PD.

Sex differences in alpha-synucleinopathies: a systematic review

Background

Past research indicates a higher prevalence, incidence, and severe clinical manifestations of alpha-synucleinopathies in men, leading to a suggestion of neuroprotective properties of female sex hormones (especially estrogen). The potential pathomechanisms of any such effect on alpha-synucleinopathies, however, are far from understood. With that aim, we undertook to systematically review, and to critically assess, contemporary evidence on sex and gender differences in alpha-synucleinopathies using a bench-to-bedside approach.

Methods

In this systematic review, studies investigating sex and gender differences in alpha-synucleinopathies (Rapid Eye Movement (REM) Behavior Disorder (RBD), Parkinson's Disease (PD), Dementia with Lewy Bodies (DLB), Multiple System Atrophy (MSA)) from 2012 to 2022 were identified using electronic database searches of PubMed, Embase and Ovid.

Results

One hundred sixty-two studies were included; 5 RBD, 6 MSA, 20 DLB and 131 PD studies. Overall, there is conclusive evidence to suggest sex-and gender-specific manifestation in demographics, biomarkers, genetics, clinical features, interventions, and quality of life in alpha-synucleinopathies. Only limited data exists on the effects of distinct sex hormones, with majority of studies concentrating on estrogen and its speculated neuroprotective effects.

Conclusion

Future studies disentangling the underlying sex-specific mechanisms of alpha-synucleinopathies are urgently needed in order to enable novel sex-specific therapeutics.

New Radiobiological Principles for the CNS Arising from Space Radiation Research

Traditionally, the brain has been regarded as a relatively insensitive late-reacting tissue, with radiologically detectable damage not being reported at doses < 60 Gy. When NASA proposed interplanetary exploration missions, it was required to conduct an intensive health and safety evaluation of cancer, cardiovascular, and cognitive risks associated with exposure to deep space radiation (SR). The SR dose that astronauts on a mission to Mars are predicted to receive is ~300 mGy. Even after correcting for the higher RBE of the SR particles, the biologically effective SR dose (<1 Gy) would still be 60-fold lower than the threshold dose for clinically detectable neurological damage. Unexpectedly, the NASA-funded research program has consistently reported that low (<250 mGy) doses of SR induce deficits in multiple cognitive functions. This review will discuss these findings and the radical paradigm shifts in radiobiological principles for the brain that were required in light of these findings. These included a shift from cell killing to loss of function models, an expansion of the critical brain regions for radiation-induced cognitive impediments, and the concept that the neuron may not be the sole critical target for neurocognitive impairment. The accrued information on how SR exposure impacts neurocognitive performance may provide new opportunities to reduce neurocognitive impairment in brain cancer patients.

Sex and Brain: The Role of Sex Chromosomes and Hormones in Brain Development and Parkinson's Disease

Sex hormones and genes on the sex chromosomes are not only key factors in the regulation of sexual differentiation and reproduction but they are also deeply involved in brain homeostasis. Their action is crucial for the development of the brain, which presents different characteristics depending on the sex of individuals. The role of these players in the brain is fundamental in the maintenance of brain function during adulthood as well, thus being important also with respect to age-related neurodegenerative diseases. In this review, we explore the role of biological sex in the development of the brain and analyze its impact on the predisposition toward and the progression of neurodegenerative diseases. In particular, we focus on Parkinson's disease, a neurodegenerative disorder that has a higher incidence in the male population. We report how sex hormones and genes encoded by the sex chromosomes could protect from the disease or alternatively predispose toward its development. We finally underline the importance of considering sex when studying brain physiology and pathology in cellular and animal models in order to better understand disease etiology and develop novel tailored therapeutic strategies.

Genetics, sex, and gender

This review aims to give an overview of what has been discovered so far and what still needs to be analyzed about how sex and gender affect the disease development. These two terms are often confused and indifferently used. In principle, the term "sex" refers to biological differences between males and females, specifically reproductive organs and their functions, while the term "gender" refers to the social context in which people live and which contributes to a subjective sexual identity, masculine or feminine. This dichotomy, however, is not so rigid and both sex and gender influence different aspects of human health, such as brain, health and aging and drug treatment and pharmacokinetics. In particular, we want to focus on genetic differences between men and women: indeed, the expression of the genes mapped on X chromosome or Y chromosome and all epigenetic interactions affect the diseases development. Finally, we will briefly outline sex and gender differences in clinical manifestations of three neurological diseases: Alzheimer's disease, Parkinson's disease, and obsessive compulsive disorder. In the era of personalized medicine, we must not forget the importance of gender medicine to promote personalized care for any kind of patients.

Complexity of Sex Differences and Their Impact on Alzheimer's Disease

Sex differences are present in brain morphology, sex hormones, aging processes and immune responses. These differences need to be considered for proper modelling of neurological diseases with clear sex differences. This is the case for Alzheimer's disease (AD), a fatal neurodegenerative disorder with two-thirds of cases diagnosed in women. It is becoming clear that there is a complex interplay between the immune system, sex hormones and AD. Microglia are major players in the neuroinflammatory process occurring in AD and have been shown to be directly affected by sex hormones. However, many unanswered questions remain as the importance of including both sexes in research studies has only recently started receiving attention. In this review, we provide a summary of sex differences and their implications in AD, with a focus on microglia action. Furthermore, we discuss current available study models, including emerging complex microfluidic and 3D cellular models and their usefulness for studying hormonal effects in this disease.

Are the digit ratio (2D:4D) and hand grip strength related to Parkinson disease in elderly males?

BACKGROUND

Sex hormones affect the pathogenesis of Parkinson patients and it has been suggested that gender is the most important factor in the development and progression of Parkinson's disease. Studies have shown that the second to fourth digit ratio (2D:4D) is affected by the prenatal testosterone and estrogen levels and can predict predisposition to disease. In addition, decreased muscle strength in people with Parkinson's has been repeatedly reported. Hand grip strength (HGS) is a suitable measure to evaluate the musculoskeletal system among the elderly and it is considered as an indicator of the overall strength of the body. This study aimed at investigating the relationship between Parkinson's disease and HGS and 2D:4D ratio.

METHODS

In this study 117 elderly men with Parkinson disease (mean age of 61.66 ± 11.28 years) and 156 healthy control subjects (mean age of 61.86 ± 6.29 years) participated. After determining the level of disability of Parkinson patients by a neurologist (level of disability in the range of 1-4), anthropometric indices (height, weight, length of the second and fourth fingers) and maximum HGS were measured.

RESULTS

Although 2D:4D ratios (right and left hand) of male patients with Parkinson's disease were higher than those of healthy males, this difference was not statistically significant (P = 0.12, P = 0.40; respectively). Conversely, HGS for the right and left hands of Parkinson patients were significantly lower than those of healthy males (P = 0.02, P = 0.03; respectively). The results showed a significant negative relationship between Parkinson disease and the right and left HGS (R = -0.16, P = 0.005; R = -0.17, P = 0.003; respectively). Parkinson disease had no significant relationship with 2D:4D of the right hand, left hand, mean finger ratio and D_R-L 2D:4D (P > 0.05). The regression results showed that the right and left HGS were not able to predict Parkinson disease (P = 0.25, P = 0.16; respectively).

CONCLUSION

We concluded that HGS was negatively associated with the Parkinson disease, but conversely, 2D:4D may not be a valuable biomarker of elevated risk of Parkinson in elderly males.

Type 1 Diabetes and the Menstrual Cycle: Where/How Does Exercise Fit in?

Regular exercise is associated with substantial health benefits for individuals with type 1 diabetes (T1D). However, the fear of hypoglycemia (low blood glucose) due to activity-induced declines in blood glucose levels acts as a major barrier to partaking in exercise in this population. For females with T1D, hormonal fluctuations during the menstrual cycle and their effects on blood glucose levels can act as an additional barrier. The impact that these cyclic changes may have on blood glucose and insulin needs and the consequent risk of hypoglycemia during or after exercise are still unknown in this population. Therefore, in this narrative review, we gathered existing knowledge about the menstrual cycle in T1D and the effects of different cyclic phases on substrate metabolism and glucose response to exercise in females with T1D to increase knowledge and understanding around exercise in this underrepresented population. This increased knowledge in such an understudied area can help to better inform exercise guidelines for females with T1D. It can also play an important role in eliminating a significant barrier to exercise in this population, which has the potential to increase activity, improve mental health and quality of life, and decrease the risk of diabetes-related complications.

Synthesis, Regulatory Factors, and Signaling Pathways of Estrogen in the Ovary

New insights have been thrown for understanding the significant role of estrogen on various systems of humans. Increasing evidences have determined the significant roles of estrogen in female reproductive system. So, the normal synthesis and secretion of estrogen play important roles in maintaining the function of tissues and organs. The ovaries are the main synthetic organs of estrogen. In this review, we summarized the current knowledge of the estrogen synthesis in the ovaries. A series of factors and signaling pathways that regulate the synthesis of estrogen are expounded in detail. Understanding the regulating factors and potential mechanism related to estrogen synthesis will be beneficial for understanding estrogen disorder related diseases and may provide novel therapeutic targets.