Foetal oestrogens and autism

Towards understanding sex differences in autism spectrum disorders

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by social deficits, repetitive behaviours and lack of empathy. Its significant genetic heritability and potential comorbidities often lead to diagnostic and therapeutic challenges. This review addresses the biological basis of ASD, focusing on the sex differences in gene expression and hormonal influences. ASD is more commonly diagnosed in males at a ratio of 4:1, indicating a potential oversight in female-specific ASD research and a risk of underdiagnosis in females. We consider how ASD manifests differently across sexes by exploring differential gene expression in female and male brains and consider how variations in steroid hormones influence ASD characteristics. Synaptic function, including excitation/inhibition ratio imbalance, is influenced by gene mutations and this is explored as a key factor in the cognitive and behavioural manifestations of ASD. We also discuss the role of micro RNAs (miRNAs) and highlight a novel mutation in miRNA-873, which affects a suite of key synaptic genes, neurexin, neuroligin, SHANK and post-synaptic density proteins, implicated in the pathology of ASD. Our review suggests that genetic predisposition, sex differences in brain gene expression, and hormonal factors significantly contribute to the presentation, identification and severity of ASD, necessitating sex-specific considerations in diagnosis and treatments. These findings advocate for personalized interventions to improve the outcomes for individuals with ASD.

Giftedness and atypical sexual differentiation: enhanced perceptual functioning through estrogen deficiency instead of androgen excess

Syndromic autism spectrum conditions (ASC), such as Klinefelter syndrome, also manifest hypogonadism. Compared to the popular Extreme Male Brain theory, the Enhanced Perceptual Functioning model explains the connection between ASC, savant traits, and giftedness more seamlessly, and their co-emergence with atypical sexual differentiation. Overexcitability of primary sensory inputs generates a relative enhancement of local to global processing of stimuli, hindering the abstraction of communication signals, in contrast to the extraordinary local information processing skills in some individuals. Weaker inhibitory function through gamma-aminobutyric acid type A (GABAA) receptors and the atypicality of synapse formation lead to this difference, and the formation of unique neural circuits that process external information. Additionally, deficiency in monitoring inner sensory information leads to alexithymia (inability to distinguish one's own emotions), which can be caused by hypoactivity of estrogen and oxytocin in the interoceptive neural circuits, comprising the anterior insular and cingulate gyri. These areas are also part of the Salience Network, which switches between the Central Executive Network for external tasks and the Default Mode Network for self-referential mind wandering. Exploring the possibility that estrogen deficiency since early development interrupts GABA shift, causing sensory processing atypicality, it helps to evaluate the co-occurrence of ASC with attention deficit hyperactivity disorder, dyslexia, and schizophrenia based on phenotypic and physiological bases. It also provides clues for understanding the common underpinnings of these neurodevelopmental disorders and gifted populations.

Hippocampal estrogens rescued the decline of synaptic plasticity after surgery and anesthesia by inhibiting microglia overactivation

BACKGROUND

Elderly patients experience postoperative cognitive impairment frequently; therefore, effective interventions are urgently needed. Central nervous inflammation characterized by microglia may promote the progression of POCD by reducing synaptic plasticity. Notably, clinical studies revealed that the incidence of female patients was significantly lower than that of male patients. Besides, the brain estrogens have an anti-inflammatory effect and regulate the microglia at the same times. This study aimed to determine whether suppressing microglia overactivation by hippocampal estrogens can rescue the decrease of synaptic plasticity after surgery and anesthesia.

METHODS

Exploratory laparotomy was used to establish the POCD model in 15-month-old male or female C57BL/6 J mice and animal behavioral tests were performed to test hippocampal-dependent memory capacity. Western blot and immunofluorescence were used to detect the microglial activation and plasticity related protein expressions. Elisa was used to detect the content of estrogens in the hippocampus. Estrogens and estrogen receptor inhibitor were used to replenish the estrogens in the brain and inhibit the effect of estrogens.

RESULTS

Surgery and anesthesia did not cause POCD in female mice (P > 0.05), while the cognitive function decreased significantly after estrogen receptor inhibitor was given(P < 0.05). Male mice experienced cognitive dysfunction after surgery and anesthesia, and their cognitive function improved after estrogens supplementation (P < 0.05). Given estrogens and estrogen receptor inhibitors at the same time, the cognitive function of male mice could not be saved (P < 0.05). By correlation analysis, there was a negative correlation between the content of hippocampal estrogens and microglia (P < 0.05). The number or degree of activation of microglia affected the synaptic plasticity, which ultimately regulated the cognitive function of mice.

CONCLUSION

Hippocampal estrogens rescued the decline of synaptic plasticity after surgery and anesthesia by inhibiting microglia overactivation.

Fetal brain growth and infant autistic traits

BACKGROUND

Structural differences exist in the brains of autistic individuals. To date only a few studies have explored the relationship between fetal brain growth and later infant autistic traits, and some have used fetal head circumference (HC) as a proxy for brain development. These findings have been inconsistent. Here we investigate whether fetal subregional brain measurements correlate with autistic traits in toddlers.

METHODS

A total of 219 singleton pregnancies (104 males and 115 females) were recruited at the Rosie Hospital, Cambridge, UK. 2D ultrasound was performed at 12-, 20- and between 26 and 30 weeks of pregnancy, measuring head circumference (HC), ventricular atrium (VA) and transcerebellar diameter (TCD). A total of 179 infants were followed up at 18-20 months of age and completed the quantitative checklist for autism in toddlers (Q-CHAT) to measure autistic traits.

RESULTS

Q-CHAT scores at 18-20 months of age were positively associated with TCD size at 20 weeks and with HC at 28 weeks, in univariate analyses, and in multiple regression models which controlled for sex, maternal age and birth weight.

LIMITATIONS

Due to the nature and location of the study, ascertainment bias could also have contributed to the recruitment of volunteer mothers with a higher than typical range of autistic traits and/or with a significant interest in the neurodevelopment of their children.

CONCLUSION

Prenatal brain growth is associated with toddler autistic traits and this can be ascertained via ultrasound starting at 20 weeks gestation.

Gonadal hormones impart male-biased behavioral vulnerabilities to immune activation via microglial mitochondrial function

There is a strong male bias in the prevalence of many neurodevelopmental disorders such as autism spectrum disorder. However, the mechanisms underlying this sex bias remain elusive. Infection during the perinatal period is associated with an increased risk of neurodevelopmental disorder development. Here, we used a mouse model of early-life immune activation that reliably induces deficits in social behaviors only in males. We demonstrate that male-biased alterations in social behavior are dependent upon microglial immune signaling and are coupled to alterations in mitochondrial morphology, gene expression, and function specifically within microglia, the innate immune cells of the brain. Additionally, we show that this behavioral and microglial mitochondrial vulnerability to early-life immune activation is programmed by the male-typical perinatal gonadal hormone surge. These findings demonstrate that social behavior in males over the lifespan are regulated by microglia-specific mechanisms that are shaped by events that occur in early development.

Measuring the Autistic Women's Experience (AWE)

We developed a Dutch questionnaire called the Autistic Women's Experience (AWE) and compared its psychometric properties to the Autism Spectrum Quotient (AQ). Whilst attenuated gender differences on the AQ have been widely replicated, this instrument may not fully capture the unique experience of autistic women. The AWE was co-developed with autistic women to include items that reflect autistic women's experience. We investigated the AWE (49 items) and compared it with the AQ (50 items) in Dutch autistic individuals (N = 153, n = 85 women) and in the general population (N = 489, n = 246 women) aged 16+. Both the AQ and AWE had excellent internal consistency and were highly and equally predictive of autism in both women and men. Whilst there was a gender difference on the AQ among non-autistic people (men > women), there was no gender difference among autistic people, confirming all earlier studies. No gender differences were detected on the AWE overall scale, yet subtle gender differences were observed on the subscales. We conclude that the AQ is valid for both genders, but the AWE provides an additional useful perspective on the characteristics of autistic women. The AWE needs further validation in independent samples using techniques that allow for testing gender biases, as well as a confirmatory factor analysis in a larger sample.

Effects of prenatal exposure to synthetic sex hormones on neurodevelopment: a biological mechanism

Since the middle of the 20th century, synthetic sex hormones (estrogens and progestins) have been administered to millions of pregnant or not women worldwide, mainly to avoid miscarriage or for comfort, although their mode of action and their effects on the mother and fetus were ignored. Despite the alerts and the description of somatic and psychiatric disorders in children exposed in utero, synthetic estrogens were prohibited for pregnant women only in the 1970s and 1980s, but some progestins are still authorized. In this review, we summarize the psychiatric disorders described in children exposed in utero to such hormones, focusing particularly on schizophrenia, bipolar disorders, severe depression, eating disorders, suicide and suicide attempts. Moreover, only in 2017 the mechanism of action of these xenohormones has started to be deciphered. Some studies showed that in the fetus exposed in utero, they alter the DNA methylation profile (mainly hypermethylation), and consequently the expression of genes implicated in neurodevelopment and in regulating the sexual organ morphogenesis and also of the promoter of estrogen receptors, located in the amygdala. These deleterious effects may be transmitted also to the next generations, thus affecting the children directly exposed and also the following generations.

Sex-specific and sex-independent steroid-related biomarkers in early second trimester maternal serum associated with autism

BACKGROUND

Prenatal exposure to maternal metabolic conditions associated with inflammation and steroid dysregulation has previously been linked to increased autism risk. Steroid-related maternal serum biomarkers have also provided insight into the in utero steroid environment for offspring who develop autism.

OBJECTIVE

This study examines the link between autism among offspring and early second trimester maternal steroid-related serum biomarkers from pregnancies enriched for prenatal metabolic syndrome (PNMS) exposure.

STUDY DESIGN

Early second trimester maternal steroid-related serum biomarkers (i.e., estradiol, free testosterone, total testosterone, and sex hormone binding globulin) were compared between pregnancies corresponding to offspring with (N = 68) and without (N = 68) autism. Multiple logistic regression analyses were stratified by sex and gestational duration. One-way ANCOVA with post hoc tests was performed for groups defined by autism status and PNMS exposure.

RESULTS

Increased estradiol was significantly associated with autism only in males (AOR = 1.13 per 100 pg/ml, 95% CI 1.01-1.27, p = 0.036) and only term pregnancies (AOR = 1.17 per 100 pg/ml, 95% CI 1.04-1.32, p = 0.010). Autism status was significantly associated with decreased sex hormone binding globulin (AOR = 0.65 per 50 nmol/L, 95% CI 0.55-0.78, p < 0.001) overall and when stratified by sex and term pregnancy status. The inverse association between sex hormone binding globulin and autism was independent of PNMS exposure.

LIMITATIONS

The relative racial and ethnic homogeneity of Utah's population limits the generalizability of study results. Although significant differences by autism status were identified in concentrations of sex hormone binding globulin overall and of estradiol in participant subgroups, differences by PNMS exposure failed to reach statistical significance, which may reflect insufficient statistical power.

CONCLUSION

Both elevated maternal serum estradiol in males only and low maternal serum sex hormone binding globulin in both sexes are associated with increased autism risk. Further investigation is merited to identify how steroid, metabolic, and inflammatory processes can interact to influence neurodevelopment in early second trimester.

Sex differences in placenta-derived markers and later autistic traits in children

Autism is more prevalent in males and males on average score higher on measures of autistic traits. Placental function is affected significantly by the sex of the fetus. It is unclear if sex differences in placental function are associated with sex differences in the occurrence of autistic traits postnatally. To assess this, concentrations of angiogenesis-related markers, placental growth factor (PlGF) and soluble fms-like tyrosine kinase (sFlt-1) were assessed in maternal plasma of expectant women in the late 1^st (mean= 13.5 [SD = 2.0] weeks gestation) and 2^nd trimesters (mean=20.6 [SD = 1.2] weeks gestation), as part of the Generation R Study, Rotterdam, the Netherlands. Subsequent assessment of autistic traits in the offspring at age 6 was performed with the 18-item version of the Social Responsiveness Scale (SRS). Associations of placental protein concentrations with autistic traits were tested in sex-stratified and cohort-wide regression models. Cases with pregnancy complications or a later autism diagnosis (n = 64) were also assessed for differences in placenta-derived markers. sFlt-1 levels were significantly lower in males in both trimesters but showed no association with autistic traits. PlGF was significantly lower in male pregnancies in the 1^st trimester, and significantly higher in the 2^nd trimester, compared to female pregnancies. Higher PlGF levels in the 2^nd trimester and the rate of PlGF increase were both associated with the occurrence of higher autistic traits (PlGF-2^nd: n = 3469,b = 0.24 [SE = 0.11], p = 0.03) in both unadjusted and adjusted linear regression models that controlled for age, sex, placental weight and maternal characteristics. Mediation analyses showed that higher autistic traits in males compared to females were partly explained by higher PlGF or a faster rate of PlGF increase in the second trimester (PlGF-2^nd: n = 3469, ACME: b = 0.005, [SE = 0.002], p = 0.004). In conclusion, higher PlGF levels in the 2^nd trimester and a higher rate of PlGF increase are associated with both being male, and with a higher number of autistic traits in the general population.

Sex and age differences in social and cognitive function in offspring exposed to late gestational hypoxia

Background

Gestational sleep apnea affects 8-26% of pregnancies and can increase the risk for autism spectrum disorder (ASD) in offspring. ASD is a neurodevelopmental disorder associated with social dysfunction, repetitive behaviors, anxiety, and cognitive impairment. To examine the relationship between gestational sleep apnea and ASD-associated behaviors, we used a chronic intermittent hypoxia (CIH) protocol between gestational days (GD) 15-19 in pregnant rats to model late gestational sleep apnea. We hypothesized that late gestational CIH would produce sex- and age-specific social, mood, and cognitive impairments in offspring.

Methods

Timed pregnant Long-Evans rats were exposed to CIH or room air normoxia from GD 15-19. Behavioral testing of offspring occurred during either puberty or young adulthood. To examine ASD-associated phenotypes, we quantified ASD-associated behaviors (social function, repetitive behaviors, anxiety-like behaviors, and spatial memory and learning), hippocampal activity (glutamatergic NMDA receptors, dopamine transporter, monoamine oxidase-A, EGR-1, and doublecortin), and circulating hormones in offspring.

Results

Late gestational CIH induced sex- and age-specific differences in social, repetitive and memory functions in offspring. These effects were mostly transient and present during puberty. In female pubertal offspring, CIH impaired social function, increased repetitive behaviors, and increased circulating corticosterone levels, but did not impact memory. In contrast, CIH transiently induced spatial memory dysfunction in pubertal male offspring but did not impact social or repetitive functions. Long-term effects of gestational CIH were only observed in female offspring, wherein CIH induced social disengagement and suppression of circulating corticosterone levels in young adulthood. No effects of gestational CIH were observed on anxiety-like behaviors, hippocampal activity, circulating testosterone levels, or circulating estradiol levels, regardless of sex or age of offspring.

Conclusions

Our results indicate that hypoxia-associated pregnancy complications during late gestation can increase the risk for ASD-associated behavioral and physiological outcomes, such as pubertal social dysfunction, corticosterone dysregulation, and memory impairments.

Shared and divergent contribution of vitamin A and oxytocin to the aetiology of autism spectrum disorder

Rare genetic variations contribute to the heterogeneity of autism spectrum disorder (ASD) and the responses to various interventions for ASD probands. However, the associated molecular underpinnings remain unclear. Herein, we estimated the association between rare genetic variations in 410 vitamin A (VA)-related genes (VARGs) and ASD aetiology using publicly available de novo mutations (DNMs), rare inherited variants, and copy number variations (CNVs) from about 50,000 ASD probands and 20,000 normal controls (discovery and validation cohorts). Additionally, given the functional relevance of VA and oxytocin, we systematically compared the similarities and differences between VA and oxytocin with respect to ASD aetiology and evaluated their potential for clinical applications. Functional DNMs and pathogenic CNVs in VARGs contributed to ASD pathogenesis in the discovery and validation cohorts. Additionally, 324 potential VA-related biomarkers were identified, 243 of which were shared with previously identified oxytocin-related biomarkers, while 81 were unique VA biomarkers. Moreover, multivariable logistic regression analysis revealed that both VA- and oxytocin-related biomarkers were able to predict ASD aetiology for individuals carrying functional DNM in corresponding biomarkers with an average precision of 0.94. As well as, convergent and divergent functions were also identified between VA- and oxytocin-related biomarkers. The findings of this study provide a basis for future studies aimed at understanding the pathophysiological mechanisms underlying ASD while also defining a set of potential molecular biomarkers for adjuvant diagnosis and intervention in ASD.

Maternal cortisol in 3rd trimester is associated with traits of neurodevelopmental disorder in offspring. Odense Child Cohort

BACKGROUND

Prenatal cortisol exposure is essential for neurodevelopment. Maternal cortisol levels could be associated with offspring autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD).

AIM

To investigate associations between maternal 3rd trimester cortisol and offspring traits of ASD and ADHD.

MATERIAL AND METHODS

Mother-child pairs were included from the prospective study Odense Child Cohort. Morning serum cortisol and 24-hour urine cortisol/cortisone were collected at gestational week 27-30. Offspring ASD and ADHD traits were assessed at age three and five years using the Child Behavior Checklist. Maternal cortisol measurements and offspring ASD and ADHD traits assessment were available in (n = 1131; 52% boys) mother-child pairs at age three and (n = 717; 54% boys) at five years of age. Maternal 24-hour urine measurement was available in a subset, at offspring three years of age (n = 300) and at five years of age (n = 217). Associations between maternal cortisol (continuous and tertiles) and offspring ASD or ADHD traits were examined in regression models adjusted for offspring sex, maternal age, pre-pregnancy BMI, parity, maternal education level, parental psychiatric disorders, and maternal smoking and stratified for offspring sex.

RESULTS

Maternal mean age ( ± SD) was 30 years ( ± 4.4) and median BMI (25%; 75% percentiles) 23.5 kg/m² (21.3; 26.6). Higher maternal serum cortisol levels were associated with higher prevalence of offspring ASD traits at three years of age in the total study cohort and in boys after stratifying for offspring sex. In the total population, tertiles of serum cortisol showed a significant dose-response relationship to ASD traits in unadjusted and adjusted models (p-values for linear trend, p < 0.01 and p = 0.02, respectively). In offspring at five years, associations between maternal cortisol and offspring ASD traits were non-significant (all p-values > 0.2). Maternal cortisol was not associated with offspring ADHD traits (all p-values > 0.07) in offspring at three and five years. Maternal 24-hour urine cortisol, cortisone, or cortisol/cortisone ratio were not associated with offspring ASD or ADHD traits.

CONCLUSION

Higher maternal serum cortisol in 3rd trimester was associated with offspring ASD traits at three years of age in the whole study cohort and in boys, but not in girls. This association was non-significant at five years of age.

The genetics of autism and steroid-related traits in prenatal and postnatal life

Background

Autism likelihood is a largely heritable trait. Autism prevalence has a skewed sex ratio, with males being diagnosed more often than females. Steroid hormones play a mediating role in this, as indicated by studies of both prenatal biology and postnatal medical conditions in autistic men and women. It is currently unclear if the genetics of steroid regulation or production interact with the genetic liability for autism.

Methods

To address this, two studies were conducted using publicly available datasets, which focused respectively on rare genetic variants linked to autism and neurodevelopmental conditions (study 1) and common genetic variants (study 2) for autism. In Study 1 an enrichment analysis was conducted, between autism-related genes (SFARI database) and genes that are differentially expressed (FDR<0.1) between male and female placentas, in 1st trimester chorionic villi samples of viable pregnancies (n=39). In Study 2 summary statistics of genome wide association studies (GWAS) were used to investigate the genetic correlation between autism and bioactive testosterone, estradiol and postnatal PlGF levels, as well as steroid-related conditions such as polycystic ovaries syndrome (PCOS), age of menarche, and androgenic alopecia. Genetic correlation was calculated based on LD Score regression and results were corrected for multiple testing with FDR.

Results

In Study 1, there was significant enrichment of X-linked autism genes in male-biased placental genes, independently of gene length (n=5 genes, p<0.001). In Study 2, common genetic variance associated with autism did not correlate to the genetics for the postnatal levels of testosterone, estradiol or PlGF, but was associated with the genotypes associated with early age of menarche in females (b=-0.109, FDR-q=0.004) and protection from androgenic alopecia for males (b=-0.135, FDR-q=0.007).

Conclusion

The rare genetic variants associated with autism appear to interact with placental sex differences, while the common genetic variants associated with autism appear to be involved in the regulation of steroid-related traits. These lines of evidence indicate that the likelihood for autism is partly linked to factors mediating physiological sex differences throughout development.

Gender Diversity and Brain Morphology Among Adolescents

Importance

Gender-diverse youths have higher rates of mental health problems compared with the general population, as shown in both clinical and nonclinical populations. Brain correlates of gender diversity, however, have been reported only among youths with gender dysphoria or in transgender individuals.

Objective

To examine brain morphologic correlates of gender diversity among adolescents from a general pediatric population who were assigned male or female at birth, separately.

Design, Setting, and Participants

This cross-sectional study was embedded in Generation R, a multiethnic population-based study conducted in Rotterdam, the Netherlands. Adolescents who were born between April 1, 2002, and January 31, 2006, and had information on self-reported or parent-reported gender diversity and structural neuroimaging at ages 13 to 15 years were included. Data analysis was performed from April 1 to July 31, 2022.

Exposures

Gender-diverse experiences among adolescents were measured with selected items from the Achenbach System of Empirically Based Assessment forms and the Gender Identity/Gender Dysphoria Questionnaire for Adolescents and Adults, as reported by adolescents and/or their parents.

Main Outcomes and Measures

High-resolution structural neuroimaging data were collected using a 3-T magnetic resonance imaging scanner (at a single site). We used linear regression models to examine differences in global brain volumetric measures between adolescents who reported gender diversity and those who did not.

Results

This study included 2165 participants, with a mean (SD) age of 13.8 (0.6) years at scanning. A total of 1159 participants (53.5%) were assigned female at birth and 1006 (46.5%) were assigned male at birth. With regard to maternal country of origin, 1217 mothers (57.6%) were from the Netherlands and 896 (42.4%) were from outside the Netherlands. Adolescents who reported gender diversity did not differ in global brain volumetric measures from adolescents who did not report gender diversity. In whole-brain, vertexwise analyses among adolescents assigned male at birth, thicker cortices in the left inferior temporal gyrus were observed among youths who reported gender diversity compared with those who did not. No associations were observed between gender diversity and surface area in vertexwise analyses.

Conclusions and Relevance

The findings of this cross-sectional study suggest that global brain volumetric measures did not differ between adolescents who reported gender diversity and those who did not. However, these findings further suggest that gender diversity in the general population correlates with specific brain morphologic features in the inferior temporal gyrus among youths who are assigned male at birth. Replication of these findings is necessary to elucidate the potential neurobiological basis of gender diversity in the general population. Future longitudinal studies should also investigate the directionality of these associations.

Exploring potential impacts of pregnancy-related maternal immune activation and extracellular vesicles on immune alterations observed in autism spectrum disorder

Autism Spectrum Disorder (ASD) is a set of neurodevelopmental disorders usually observed in early life, with impacts on behavioral and social skills. Incidence of ASD has been dramatically increasing worldwide, possibly due to increase in awareness/diagnosis as well as to genetic and environmental triggers. Currently, it is estimated that ∼1% of the world population presents ASD symptoms. In addition to its genetic background, environmental and immune-related factors also influence the ASD etiology. In this context, maternal immune activation (MIA) has recently been suggested as a component potentially involved in ASD development. In addition, extracellular vesicles (EVs) are abundant at the maternal-fetal interface and are actively involved in the immunoregulation required for a healthy pregnancy. Considering that alterations in concentration and content of EVs have also been associated with ASD, this article raises a debate about the potential roles of EVs in the processes surrounding MIA. This represents the major differential of the present review compared to other ASD studies. To support the suggested correlations and hypotheses, findings regarding the roles of EVs during pregnancy and potential influences on ASD are discussed, along with a review and update concerning the participation of infections, cytokine unbalances, overweight and obesity, maternal anti-fetal brain antibodies, maternal fever, gestational diabetes, preeclampsia, labor type and microbiota unbalances in MIA and ASD.

Mini-puberty testosterone and infant autistic traits

Background

Levels of steroid hormones in the first three months of life, a period referred to as 'mini-puberty', are one of the earliest physiological differences between typical males and females postnatally. Autistic traits also show consistent typical sex differences in later infancy, after the 18th month of life. Previous studies have shown prenatal testosterone is associated with later levels of autistic traits. Studies testing if postnatal testosterone levels are associated with autistic traits have reported null results. No studies to date have investigated mini-puberty longitudinally or tested for interactions with baseline sex differences or familial likelihood of autism.

Methods

The 'Cambridge Human Imaging and Longitudinal Development Study' (CHILD) is a prospective enriched cohort study in Cambridge, UK. It includes physiological measurements in early infancy, as well as neurodevelopmental follow-ups over the first two years of life. A subset of the cohort also includes children with a family history of autism (a diagnosed parent or sibling). Salivary testosterone levels were assessed at two time-points, just after the 2nd and 6th month of life. Autistic traits were measured using the Quantitative Checklist of Autism in Toddlers (Q-CHAT) when the children were 18 months of age.

Results

Salivary testosterone levels were significantly higher during 'mini-puberty' in the 2nd and 3rd month of life, compared to after the 6th month of life, in both males and females. There was no significant sex difference at either time-point. Log-transformed testosterone levels were not associated with autistic traits (Q-CHAT). There was no interaction effect with infant sex, autism family history or baseline testosterone levels after mini-puberty (at >6 months of age).

Conclusion

Both male and female infants have elevated levels of salivary testosterone during mini-puberty but in this relatively small sample this was not associated with their later autistic traits at 18 months or their family history of autism. This suggests that prenatal rather than postnatal testosterone levels are more relevant for understanding the causes of autism. Future studies should test these relationships in larger samples.

Sex and gender in neurodevelopmental conditions

Health-related conditions often differ qualitatively or quantitatively between individuals of different birth-assigned sexes and gender identities, and/or with different gendered experiences, requiring tailored care. Studying the moderating and mediating effects of sex-related and gender-related factors on impairment, disability, wellbeing and health is of paramount importance especially for neurodivergent individuals, who are diagnosed with neurodevelopmental conditions with uneven sex/gender distributions. Researchers have become aware of the myriad influences that sex-related and gender-related variables have on the manifestations of neurodevelopmental conditions, and contemporary work has begun to investigate the mechanisms through which these effects are mediated. Here we describe topical concepts of sex and gender science, summarize current knowledge, and discuss research and clinical challenges related to autism, attention-deficit/hyperactivity disorder and other neurodevelopmental conditions. We consider sex and gender in the context of epidemiology, behavioural phenotypes, neurobiology, genetics, endocrinology and neighbouring disciplines. The available evidence supports the view that sex and gender are important contributors to the biological and behavioural variability in neurodevelopmental conditions. Methodological caveats such as frequent conflation of sex and gender constructs, inappropriate measurement of these constructs and under-representation of specific demographic groups (for example, female and gender minority individuals and people with intellectual disabilities) limit the translational potential of research so far. Future research and clinical implementation should integrate sex and gender into next-generation diagnostics, mechanistic investigations and support practices.

Steroid hormone pathways, vitamin D and autism: a systematic review

The origins of the male preponderance in autism incidence remain unclear. The idea that perinatal factors associated with sex differentiation (e.g., steroid hormone pathways) may increase the possibility of the emergence of autism is complementary to the hypothesis that female individuals are intrinsically less likely to develop autism. Empirical evidence for the mechanistic roles of in utero steroid hormones in autism etiology is accumulating but inconsistent. We conducted a systematic review using rigorous criteria for the measurements of steroids and vitamin D exposure, to summarize the potential contributing roles of prenatal and early postnatal steroids and vitamin D alterations to the emergence of autism. We searched PubMed, PsychInfo, Scopus, and included 22 studies for qualitative synthesis. Among them, six studies examined the association of autism diagnoses in offspring and levels of steroids and precursor steroid hormones in the fetal environment, eight studies examined the associations between autism and maternal and fetal blood vitamin D levels during pregnancy and at birth, and eight studies examined the associations between offspring autism diagnoses and maternal hyperandrogenemia diagnosed before pregnancy. We identified promising and complex results regarding the relations between steroid metabolism and autism. The interpretation of findings was limited by the mostly observational study designs, insufficient investigation of the effects of offspring sex, confounders and their cumulative effects on the development of the child, and unclear impact of the timing of steroids exposure and their effects on fetal neurodevelopment.

Autism-like behavior of murine offspring induced by prenatal exposure to progestin is associated with gastrointestinal dysfunction due to claudin-1 suppression

Autism spectrum disorders (ASD) are associated with the contribution of many prenatal risk factors; in particular, the sex hormone progestin and vitamin D receptor (VDR) are associated with gastrointestinal (GI) symptoms in ASD development, although the related mechanism remains unclear. We investigated the possible role and mechanism of progestin 17-hydroxyprogesterone caproate (17-OHPC) exposure-induced GI dysfunction and autism-like behaviours (ALB) in mouse offspring. An intestine-specific VDR-deficient mouse model was established for prenatal treatment, while transplantation of haematopoietic stem cells (HSCT) with related gene manipulation was used for postnatal treatment for 17-OHPC exposure-induced GI dysfunction and ALB in mouse offspring. The in vivo mouse experiments found that VDR deficiency mimics prenatal 17-OHPC exposure-mediated GI dysfunction, but has no effect on 17-OHPC-mediated autism-like behaviours (ALB) in mouse offspring. Furthermore, prenatal 17-OHPC exposure induces CLDN1 suppression in intestine epithelial cells, and transplantation of HSCT with CLDN1 expression ameliorates prenatal 17-OHPC exposure-mediated GI dysfunction, but has no effect on 17-OHPC-mediated ALB in offspring. In conclusion, prenatal 17-OHPC exposure triggers GI dysfunction in autism-like mouse offspring via CLDN1 suppression, providing a possible explanation for the involvement of CLDN1 and VDR in prenatal 17-OHPC exposure-mediated GI dysfunction with ASD.

Novel insights into the immune cell landscape and gene signatures in autism spectrum disorder by bioinformatics and clinical analysis

The pathogenesis of autism spectrum disorder (ASD) is not well understood, especially in terms of immunity and inflammation, and there are currently no early diagnostic or treatment methods. In this study, we obtained six existing Gene Expression Omnibus transcriptome datasets from the blood of ASD patients. We performed functional enrichment analysis, PPI analysis, CIBERSORT algorithm, and Spearman correlation analysis, with a focus on expression profiling in hub genes and immune cells. We validated that monocytes and nonclassical monocytes were upregulated in the ASD group using peripheral blood (30 children with ASD and 30 age and sex-matched typically developing children) using flow cytometry. The receiver operating characteristic curves (PSMC4 and ALAS2) and analysis stratified by ASD severity (LIlRB1 and CD69) showed that they had predictive value using the "training" and verification groups. Three immune cell types - monocytes, M2 macrophages, and activated dendritic cells - had different degrees of correlation with 15 identified hub genes. In addition, we analyzed the miRNA-mRNA network and agents-gene interactions using miRNA databases (starBase and miRDB) and the DSigDB database. Two miRNAs (miR-342-3p and miR-1321) and 23 agents were linked with ASD. These findings suggest that dysregulation of the immune system may contribute to ASD development, especially dysregulation of monocytes and monocyte-derived cells. ASD-related hub genes may serve as potential predictors for ASD, and the potential ASD-related miRNAs and agents identified here may open up new strategies for the prevention and treatment of ASD.

Sex hormone receptor expression in children with autism spectrum disorder.. [DOI: 10.21203/rs.3.rs-2345028/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background Sex hormones, especially estrogen, which binds to estrogen receptor β (ERβ), play a vital role in the pathogenesis of mental disorders such as autism spectrum disorder (ASD). The purpose of this study was to analyze the serum levels of hormone receptors, including ERβ, progesterone receptor (PGR) and androgen receptor (AR), and compare these levels between children with ASD and typically developing (TD) children. We also investigated the relationships of ERβ mRNA levels with ASD core symptoms, sleep, and developmental quotients (DQs) from the Gesell Developmental Schedules (GDS) among children with ASD. Methods We compared the mRNA levels of ERβ, AR, and PGR between 56 children with ASD and 37 TD children by using quantitative real-time PCR. Then, a correlation analysis was performed to determine the correlations of ERβ mRNA levels with Childhood Autism Rating Scale (CARS), Autism Behavior Checklist (ABC), and Children’s Sleep Habits Questionnaire (CHSQ) scores as well as DQs among ASD children. Results We found that serum mRNA levels of ERβ in ASD children were significantly lower than those in the TD group. However, we found no correlations of the ERβ mRNA level with CARS, ABC, and CHSQ scores as well as DQs on each GDS domain among ASD children. Conclusions Elevated ERβ mRNA levels in peripheral blood may be related to ASD but this association needs to be validated with a larger sample size.

The Link Between Autism and Sex-Related Neuroanatomy, and Associated Cognition and Gene Expression

OBJECTIVE

The male preponderance in prevalence of autism is among the most pronounced sex ratios across neurodevelopmental conditions. The authors sought to elucidate the relationship between autism and typical sex-differential neuroanatomy, cognition, and related gene expression.

METHODS

Using a novel deep learning framework trained to predict biological sex based on T₁-weighted structural brain images, the authors compared sex prediction model performance across neurotypical and autistic males and females. Multiple large-scale data sets comprising T₁-weighted MRI data were employed at four stages of the analysis pipeline: 1) pretraining, with the UK Biobank sample (>10,000 individuals); 2) transfer learning and validation, with the ABIDE data sets (1,412 individuals, 5-56 years of age); 3) test and discovery, with the EU-AIMS/AIMS-2-TRIALS LEAP data set (681 individuals, 6-30 years of age); and 4) specificity, with the NeuroIMAGE and ADHD200 data sets (887 individuals, 7-26 years of age).

RESULTS

Across both ABIDE and LEAP, features positively predictive of neurotypical males were on average significantly more predictive of autistic males (ABIDE: Cohen's d=0.48; LEAP: Cohen's d=1.34). Features positively predictive of neurotypical females were on average significantly less predictive of autistic females (ABIDE: Cohen's d=1.25; LEAP: Cohen's d=1.29). These differences in sex prediction accuracy in autism were not observed in individuals with ADHD. In autistic females, the male-shifted neurophenotype was further associated with poorer social sensitivity and emotional face processing while also associated with gene expression patterns of midgestational cell types.

CONCLUSIONS

The results demonstrate an increased resemblance in both autistic male and female individuals' neuroanatomy with male-characteristic patterns associated with typically sex-differential social cognitive features and related gene expression patterns. The findings hold promise for future research aimed at refining the quest for biological mechanisms underpinning the etiology of autism.

Sex Differences in Neurodevelopmental Disorders: A Key Role for the Immune System

Sex differences are prominent defining features of neurodevelopmental disorders. Understanding the sex biases in these disorders can shed light on mechanisms leading to relative risk and resilience for the disorders, as well as more broadly advance our understanding of how sex differences may relate to brain development. The prevalence of neurodevelopmental disorders is increasing, and the two most common neurodevelopmental disorders, Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) exhibit male-biases in prevalence rates and sex differences in symptomology. While the causes of neurodevelopmental disorders and their sex differences remain to be fully understood, increasing evidence suggests that the immune system plays a critical role in shaping development. In this chapter we discuss sex differences in prevalence and symptomology of ASD and ADHD, review sexual differentiation and immune regulation of neurodevelopment, and discuss findings from human and rodent studies of immune dysregulation and perinatal immune perturbation as they relate to potential mechanisms underlying neurodevelopmental disorders. This chapter will give an overview of how understanding sex differences in neuroimmune function in the context of neurodevelopmental disorders could lend insight into their etiologies and better treatment strategies.

Maternal androgens and autism spectrum disorder in the MARBLES prospective cohort study

Background

Maternal hormonal risk factors for autism spectrum disorder (ASD) in offspring could intersect genetic and environmental risk factors.

Objectives

This analysis explored ASD risk in association with maternal testosterone, androstenedione, and dehydroepiandrosterone (DHEA) measured in first, second, and third trimesters of pregnancy.

Methods

MARBLES is a prospective pregnancy cohort study based at the MIND Institute in Northern California that enrolls mothers who have at least one child previously diagnosed with ASD and are expecting, or planning to have another child. At 36 months the younger sibling is clinically classified as having ASD, or as non-typically developing (Non-TD), or typically developing (TD). Maternal androgens during pregnancy were measured in serum samples from 196 mothers. Multivariable logistic regression models estimated risk of ASD and Non-TD in offspring compared to TD, in relation to the log-transformed maternal androgen concentrations, at each trimester.

Results

Non-significant associations were observed, and borderline significant associations were only observed in some stratified unadjusted models. Second trimester maternal testosterone was non-significantly associated with ASD in female offspring, although not after adjustment, aRR 1.54 (95% CI 0.71, 3.33), and second trimester maternal DHEA was non-significantly associated with non-TD in male offspring, again not after adjustment, aRR 0.50 (95% CI 0.21, 1.21). Secondary analysis suggested that third trimester androgen concentrations in mothers with male offspring had significant or near significant associations with their child's Social Responsiveness Scale score.

Conclusion

No significant associations were found between maternal androgen concentrations and risk of ASD or Non-TD in the child.

A longitudinal examination of perinatal testosterone, estradiol and vitamin D as predictors of handedness outcomes in childhood and adolescence

The developmental origins of handedness remain elusive, though very early emergence suggests individual differences manifesting in utero could play an important role. Prenatal testosterone and Vitamin D exposure are considered, yet findings and interpretations remain equivocal. We examined n = 767 offspring from a population-based pregnancy cohort (The Raine Study) for whom early biological data and childhood/adolescent handedness data were available. We tested whether 18-week maternal circulatory Vitamin D (25[OH]D), and testosterone and estradiol from umbilical cord blood sampled at birth predicted variance in direction of hand preference (right/left), along with right- and left-hand speed, and the strength and direction of relative hand skill as measured by a finger-tapping task completed at 10 (Y10) and/or 16 (Y16) years. Although higher concentrations of Vitamin D predicted more leftward and less lateralized (regardless of direction) relative hand skill profiles, taken as a whole, statistically significant findings typically did not replicate across time-point (Y10/Y16) or sex (male/female) and were rarely detected across different (bivariate/multivariate) levels of analysis. Considering the number of statistical tests and generally inconsistent findings, our results suggest that perinatal testosterone and estradiol contribute minimally, if at all, to subsequent variance in handedness. Vitamin D, however, may be of interest in future studies.

Effect of a High Estrogen Level in Early Pregnancy on the Development and Behavior of Marmoset Offspring

The use of assisted reproductive technology (ART) has risen steadily worldwide over the past 3 decades and helps many infertile families. However, ART treatments lead to an abnormal internal environment in the uterus, which may increase the risks of health problems for the offspring. Higher maternal estradiol (E₂) is a notable feature in women who use ART treatments, and this has been suggested as a key factor for the risk of diseases in the offspring. In the current study, we have established a marmoset model with a high E₂ level in early pregnancy to examine its potential risk to the development and behavior of the offspring. In comparison with the normal group, babies of the high E₂ group exhibited lower average survival rates and birth weights. However, those who survived in the high E₂ group demonstrated normal vocal production with rich call repertoires, normal speed during locomotion, and normal behaviors in the home cage. In contrast to the normal group, surviving babies of the high E₂ group spent more time sleeping during development without signs of sleep disorders. In summary, our study revealed that high estrogen in early pregnancy may cause low survival rates and birth weights of the offspring, though the surviving infants did not show obvious behavioral deficiencies during development. The current study is a valuable and highly important non-human primate study for evaluating the safety of ART treatments. However, it is worth noting that some results did not reach the significant level, which may be due to the small sample size caused by animal shortage stemming from the COVID-19 epidemic.

Salivary testosterone in male and female youth with and without autism spectrum disorder: considerations of development, sex, and diagnosis

BACKGROUND

Puberty is characterized by significant physical, hormonal, and psychological changes, which may be especially challenging for individuals with autism spectrum disorder (ASD). Although the etiology of ASD remains uncertain, studies suggest imbalances in hormones, such as testosterone, may modulate the autism phenotype. While differences in fetal and postnatal testosterone have been reported, there is limited literature regarding testosterone variations during adolescence in ASD. We investigated morning salivary testosterone levels in youth with ASD and typical development (TD) to explore hypothesized differences, expecting elevated hormonal levels in ASD compared to TD.

METHODS

Youth with ASD (n = 140) and TD (n = 104), ages 10 to 13 years, were enrolled as part of a longitudinal study on pubertal development. Pubertal stage was determined by gold standard physical examination, and salivary testosterone was collected in the morning immediately upon waking and 30 min after waking and averaged across 3 days. Diagnostic (ASD/TD) and sex (male/female) differences, as well as interactions with age and puberty, were examined using robust linear mixed effect models.

RESULTS

Youth with ASD showed significantly elevated testosterone concentrations compared to same-age TD peers. After the inclusion of natural cubic splines to account for nonlinearity in age, a significant age-by-sex interaction emerged with distinct developmental slopes for males and females. At younger ages, females had higher testosterone, until about 11.5 years of age, when levels began to plateau, while male testosterone concentrations continued to rapidly increase and surpass females. As expected, more advanced pubertal development was associated with elevated testosterone. In contrast, no significant effect of parent-reported social communication symptoms was observed.

LIMITATIONS

Limitations include an unequal sex distribution, non-representative sample (e.g., cognition and race/ethnicity), and inability to examine afternoon/evening testosterone due to detection limits.

CONCLUSIONS

Testosterone may play a unique role in the presentation of ASD, especially during periods of dynamic hormonal changes including puberty. Inherent developmental (age, puberty) and sex-based (male, female) factors play a more prominent role in changes in testosterone levels during adolescence. Even so, future research is warranted to determine the differential expression and impact of exposure to excess testosterone during the pubertal transition for youth with ASD.

Drug repurposing candidates to treat core symptoms in autism spectrum disorder

Autism spectrum disorder (ASD) is characterized by high heritability and clinical heterogeneity. The main core symptoms are social communication deficits. There are no medications approved for the treatment of these symptoms, and medications used to treat non-specific symptoms have serious side effects. To identify potential drugs for repurposing to effectively treat ASD core symptoms, we studied ASD risk genes within networks of protein-protein interactions of gene products. We first defined an ASD network from network-based analyses, and identified approved drugs known to interact with proteins within this network. Thereafter, we evaluated if these drugs can change ASD-associated gene expression perturbations in genes in the ASD network. This was done by analyses of drug-induced versus ASD-associated gene expression, where opposite gene expression perturbations in drug versus ASD indicate that the drug could counteract ASD-associated perturbations. Four drugs showing significant (p < 0.05) opposite gene expression perturbations in drug versus ASD were identified: Loperamide, bromocriptine, drospirenone, and progesterone. These drugs act on ASD-related biological systems, indicating that these drugs could effectively treat ASD core symptoms. Based on our bioinformatics analyses of ASD genetics, we shortlist potential drug repurposing candidates that warrant clinical translation to treat core symptoms in ASD.

Where Sex Meets Gender: How Sex and Gender Come Together to Cause Sex Differences in Mental Illness

Sex differences are prevalent in multiple mental disorders. Internalizing disorders are more commonly diagnosed in women, whereas externalizing and neurodevelopmental disorders are more often diagnosed in men. Significant sex/gender differences are reported in prevalence, symptom profile, age of onset, comorbidities, functional impairment, prognosis, as well as in responses to various treatments. In this conceptual article, we discuss theories and empirical studies of sex- and gender-related influences in mental health, by focusing on three examples: autism spectrum disorder (ASD), acknowledged as a disorder whose roots are mainly biological; eating disorders, whose origins are considered to be mainly psychosocial, and posttraumatic stress disorder (PTSD), an environmentally caused disorder with both psychosocial and biological underpinnings. We examine the ways in which sex differences emerge, from conception through adulthood. We also examine how gender dichotomies in exposures, expectations, role assumptions, and cultural traditions impact the expression of our three selected mental illnesses. We are especially interested in how sex-based influences and gender-based influences interact with one another to affect mental illness. We suggest that sex and gender are multi-faceted and complex phenomena that result in variations, not only between men and women, but also within each sex and gender through alterations in genes, hormone levels, self-perceptions, trauma experiences, and interpersonal relationships. Finally, we propose a conceptual diatheses-stress model, depicting how sex and gender come together to result in multiple sex/gender differences across mental disorders. In our model, we categorize diatheses into several categories: biological, intrapersonal, interpersonal, and environmental. These diatheses interact with exposure to stressors, ranging from relatively minor to traumatic, which allows for the sometimes bidirectional influences of acute and long-term stress responses. Sex and gender are discussed at every level of the model, thereby providing a framework for understanding and predicting sex/gender differences in expression, prevalence and treatment response of mental disorders. We encourage more research into this important field of study.

Association between resting-state functional brain connectivity and gene expression is altered in autism spectrum disorder

Gene expression covaries with brain activity as measured by resting state functional magnetic resonance imaging (MRI). However, it is unclear how genomic differences driven by disease state can affect this relationship. Here, we integrate from the ABIDE I and II imaging cohorts with datasets of gene expression in brains of neurotypical individuals and individuals with autism spectrum disorder (ASD) with regionally matched brain activity measurements from fMRI datasets. We identify genes linked with brain activity whose association is disrupted in ASD. We identified a subset of genes that showed a differential developmental trajectory in individuals with ASD compared with controls. These genes are enriched in voltage-gated ion channels and inhibitory neurons, pointing to excitation-inhibition imbalance in ASD. We further assessed differences at the regional level showing that the primary visual cortex is the most affected region in ASD. Our results link disrupted brain expression patterns of individuals with ASD to brain activity and show developmental, cell type, and regional enrichment of activity linked genes.

Gene expression patterns have been associated with functional activity patterns in the brain. Here the authors determine how gene expression patterns in the human brain supports brain phenotypes obtained from resting state fMRI imaging, identifying brain regions and genes relevant to autism.

Selective effects of perinatal estrogen on proliferation and new neurons in hippocampus and piriform cortex of rats at weaning

BACKGROUND

A recent report links heightened prenatal amniotic estrogen levels to an increased risk of autism spectrum disorder (ASD). In this study, we examined the developmental effects of perinatal estrogen treatment on stem cell activity in weaned rats.

METHODS

Sprague-Dawley rats received ethinyl estradiol (EE2, 10µg/kg/day) or vehicle orally from gestational day 6 until parturition. Offspring were then treated with the same daily dose from postnatal days (PNDs) 1-21. The effects of perinatal estrogen treatment on stem cell activities in the subgranular zone (SGZ) of the hippocampus and the piriform cortex were evaluated in male and female rat pups.

RESULTS

EE₂ treatment increased the total Ki67-immunoreactive (Ki67-ir) cell counts in the SGZ of males and females (p<0.05). However, no treatment or sex differences were detectable in the density of the doublecortin (DCX)-immunoreactive (DCX-ir) deposits in the hippocampus. In the piriform cortex, no treatment or sex differences were detected in Ki67-ir cell counts. However, the EE₂ treatment significantly reduced the DCX-ir cell count in male, but not female rats (male EE₂ group=29₂±22/mm², male vehicle group=402±19/mm², female EE² group=34₂±15/mm², female vehicle group=331±9/mm²).

CONCLUSIONS

Perinatal estrogen treatment increased hippocampal Ki67-ir cell counts in both sexes and selectively reduced DCX-ir cell counts in the piriform cortex of males. These data suggest that exposure to abnormally high levels of estrogens early in life may have an impact on neural cell development. Alterations in development so early in life may have long-term cognitive impact.

Evidence of partner similarity for autistic traits, systemizing, and theory of mind via facial expressions

It has been hypothesised that romantic partners are more similar than chance in relation to autistic traits. To test this theory, we recruited n = 105 heterosexual couples and examined within-couple correlations for autistic traits [measured using the Autism Spectrum Quotient (AQ)], empathizing [measured using the Empathy Quotient (EQ)], and systemizing [measured using the Systemizing Quotient-Revised (SQ-R)]. For a subsample that attended the lab (n = 58 couples), we also investigated theory of mind via facial expressions using the Reading the Mind in the Eyes Test (RMET) and attention to detail, a component within systemizing, using the Embedded Figures Task (EFT). Variable-centred analyses revealed positive within-couple correlations for all measures except EQ, although these effects were only statistically significant for unmarried couples and not for married/engaged couples. Follow-up analyses indicated that the observed couple similarity effects are likely consistent with people pairing with those more similar than chance (initial assortment) rather than becoming alike over time (convergence), and to seeking out self-resembling partners (active assortment) rather than pairing in this manner via social stratification processes (social homogamy). Additionally, a significant within-couple correlation for autistic traits was observed at the meta-analytic level. However, it should be noted that the meta-analytic effect size estimate was small (r = 0.153) and indicates that only ~ 2% of variance in a person’s score on a phenotypic measure of autistic traits can be predicted by that of their partner.

Autistic Traits, Empathizing-Systemizing, and Gender Diversity

Previous research indicates a link between autism and transgender and gender-diverse identities, though the association is not yet fully understood. The current study examined autistic traits (Autism Spectrum Quotient [AQ]), empathizing (Empathizing Quotient-Short [EQ-S]), and systemizing (Systemizing Quotient-Short [SQ-S]) in a sample of 89 adults and aimed to test whether gender-diverse individuals exhibit cognitive profiles consistent with predictions derived from the Extreme Male Brain (EMB) theory. As most research has considered only cisgender people, we recruited a more diverse sample by contacting > 200 UK LGBTQ+ organizations and posting on social media. A range of non-cisgender identities (e.g., transgender male, transgender female, non-binary, genderqueer, transmasculine) and non-heterosexual orientations (e.g., bisexual) were represented, and participants were categorized into one of four groups: (1) assigned female at birth but does not identify as female (transgender AFAB) (n = 32), (2) cisgender female (n = 21), (3) assigned male at birth but does not identify as male (transgender AMAB) (n = 18), and (4) cisgender male (n = 18). After controlling for age and autism diagnostic status, transgender AFAB participants had marginally higher AQ scores, and significantly higher SQ-S and systemizing-relative-to-empathizing (D) scores, compared with the cisgender female group. No such differences were detected between the transgender AMAB and cisgender male groups. Our findings are broadly in line with predictions derived from the EMB theory, though as no transgender AFAB participants reported being heterosexual, it was not possible to determine whether these effects relate specifically to gender identity, to sexual orientation, or to both.

Elevated prenatal maternal sex hormones, but not placental aromatase, are associated with child neurodevelopment

Fetal exposure to testosterone may contribute to vulnerability for autism spectrum disorder (ASD). It is hypothesized that placental aromatase prevents fetal exposure to maternal testosterone, however, this pathway and the implications for child neurodevelopment have not been fully explored. We examined the relationships between prenatal maternal testosterone and estradiol at 19.2 ± 1.3 weeks, cord blood testosterone and estradiol at birth, placental aromatase mRNA expression, and neurodevelopment using the Social Communication Questionnaire (SCQ), the Behavioral Assessment System for Children, 3rd Edition (BASC-3), and the Empathizing Quotient for Children (EQ-C) at 4.5-6.5 years of age in a sample of 270 Nulliparous-Mothers-to-be (nuMoM2b) study participants. Maternal testosterone levels were positively associated with SCQ scores, but the association was not significant after adjusting for maternal age at delivery, nor was there a significant interaction with sex. Maternal estradiol levels were negatively associated with BASC-3 Clinical Probability scores among males (n = 139). We report a significant interaction effect of cord blood testosterone and fetal sex on both total SCQ scores and t-scores on the Developmental Social Disorders subscale. Placental aromatase was not associated with any neurodevelopmental or hormone measure, but under conditions of low placental aromatase expression, high maternal testosterone was positively associated with SCQ scores in males (n = 46). No other associations between hormone levels and neurodevelopment were significant. Our findings provide a foundation for further investigation of the mechanisms through which maternal sex hormones and placental steroidogenesis may affect fetal hormone production and neurobehavior.

An investigation of a novel broad autism phenotype: increased facial masculinity among parents of children on the autism spectrum

The broad autism phenotype commonly refers to sub-clinical levels of autistic-like behaviour and cognition presented in biological relatives of autistic people. In a recent study, we reported findings suggesting that the broad autism phenotype may also be expressed in facial morphology, specifically increased facial masculinity. Increased facial masculinity has been reported among autistic children, as well as their non-autistic siblings. The present study builds on our previous findings by investigating the presence of increased facial masculinity among non-autistic parents of autistic children. Using a previously established method, a 'facial masculinity score' and several facial distances were calculated for each three-dimensional facial image of 192 parents of autistic children (58 males, 134 females) and 163 age-matched parents of non-autistic children (50 males, 113 females). While controlling for facial area and age, significantly higher masculinity scores and larger (more masculine) facial distances were observed in parents of autistic children relative to the comparison group, with effect sizes ranging from small to medium (0.16 ≤ d ≤ .41), regardless of sex. These findings add to an accumulating evidence base that the broad autism phenotype is expressed in physical characteristics and suggest that both maternal and paternal pathways are implicated in masculinized facial morphology.

Sex-related brain connectivity correlates of compensation in adults with autism: insights into female protection

The male preponderance in autism spectrum disorder (ASD) led to the hypothesis that aspects of female biology are protective against ASD. Females with ASD (ASD-F) report more compensatory behaviors (i.e. "camouflaging") to overcome ASD-related social differences, which may be a mechanism of protection. No studies have examined sex-related brain pathways supporting camouflaging in ASD-F, despite its potential to inform mechanisms underlying the ASD sex bias. We used functional connectivity (FC) to investigate "sex-atypical" and "sex-typical" FC patterns linked to camouflaging in adults with ASD and examined multimodal coherence of findings via structural connectometry. Exploratory associations with cognitive/emotional functioning examined the adaptive nature of FC patterns. We found (i) "sex-atypical" FC patterns linked to camouflaging in the hypothalamus and precuneus and (ii) "sex-typical" patterns in the right anterior cingulate and anterior parahippocampus. Higher hypothalamic FC with a limbic reward cluster also correlated with better cognitive control/emotion recognition. Structural connectometry validated FC results with consistent brain pathways/effect patterns implicated in ASD-F. In summary, "male-typical" and "female-typical" brain connectivity patterns support camouflaging in ASD-F in circuits implicated in reward, emotion, and memory retrieval. "Sex-atypical" results are consistent with fetal steroidogenic/neuroinflammatory hypotheses. However, female genetics/biology may contribute to "female-typical" patterns implicated in camouflaging.

Maternal diabetes-mediated RORA suppression contributes to gastrointestinal symptoms in autism-like mouse offspring

BACKGROUND

Retinoic acid-related orphan receptor alpha (RORA) has been reported to be suppressed in autistic patients and is associated with autism spectrum disorders (ASD), although the potential role and mechanism of RORA on gastrointestinal (GI) symptoms in ASD patients is still not reported. In this study, we aim to investigate the contribution of RORA to GI symptoms through a maternal diabetes-mediated autism-like mouse model.

RESULTS

Male offspring of diabetic dams were treated with either superoxide dismutase (SOD) mimetic MnTBAP or RORA agonist SR1078, or were crossbred with intestine epithelial cells (IEC)-specific RORA knockout (RORA^-/-) mouse. Gene expression, oxidative stress and inflammation were measured in brain tissues, peripheral blood mononuclear cells (PBMC) and IEC, and GI symptoms were evaluated. Our results showed that SOD mimetic MnTBAP completely, while RORA agonist SR1078 partly, reversed maternal diabetes-mediated oxidative stress and inflammation in the brain, PBMC and IEC, as well as GI symptoms, including intestine permeability and altered gut microbiota compositions. IEC-specific RORA deficiency either mimicked or worsened maternal diabetes-mediated GI symptoms as well as oxidative stress and inflammation in IEC, while there was little effect on maternal diabetes-mediated autism-like behaviors.

CONCLUSIONS

We conclude that RORA suppression contributes to maternal diabetes-mediated GI symptoms in autism-like mouse offspring, this study provides a potential therapeutical target for maternal diabetes-mediated GI symptoms in offspring through RORA activation.

Placental genomics mediates genetic associations with complex health traits and disease

As the master regulator in utero, the placenta is core to the Developmental Origins of Health and Disease (DOHaD) hypothesis but is historically understudied. To identify placental gene-trait associations (GTAs) across the life course, we perform distal mediator-enriched transcriptome-wide association studies (TWAS) for 40 traits, integrating placental multi-omics from the Extremely Low Gestational Age Newborn Study. At $$P \; < \; 2.5\times {10}^{-6}$$ P < 2.5 × 10 − 6 , we detect 248 GTAs, mostly for neonatal and metabolic traits, across 176 genes, enriched for cell growth and immunological pathways. In aggregate, genetic effects mediated by placental expression significantly explain 4 early-life traits but no later-in-life traits. 89 GTAs show significant mediation through distal genetic variants, identifying hypotheses for distal regulation of GTAs. Investigation of one hypothesis in human placenta-derived choriocarcinoma cells reveal that knockdown of mediator gene EPS15 upregulates predicted targets SPATA13 and FAM214A, both associated with waist-hip ratio in TWAS, and multiple genes involved in metabolic pathways. These results suggest profound health impacts of placental genomic regulation in developmental programming across the life course.

Maternal diabetes-mediated RORA suppression in mice contributes to autism-like offspring through inhibition of aromatase

Retinoic acid-related orphan receptor alpha (RORA) suppression is associated with autism spectrum disorder (ASD) development, although the mechanism remains unclear. In this study, we aim to investigate the potential effect and mechanisms of RORA suppression on autism-like behavior (ALB) through maternal diabetes-mediated mouse model. Our in vitro study in human neural progenitor cells shows that transient hyperglycemia induces persistent RORA suppression through oxidative stress-mediated epigenetic modifications and subsequent dissociation of octamer-binding transcription factor 3/4 from the RORA promoter, subsequently suppressing the expression of aromatase and superoxide dismutase 2. The in vivo mouse study shows that prenatal RORA deficiency in neuron-specific RORA null mice mimics maternal diabetes-mediated ALB; postnatal RORA expression in the amygdala ameliorates, while postnatal RORA knockdown mimics, maternal diabetes-mediated ALB in offspring. In addition, RORA mRNA levels in peripheral blood mononuclear cells decrease to 34.2% in ASD patients (n = 121) compared to the typically developing group (n = 118), and the related Receiver Operating Characteristic curve shows good sensitivity and specificity with a calculated 84.1% of Area Under the Curve for ASD diagnosis. We conclude that maternal diabetes contributes to ALB in offspring through suppression of RORA and aromatase, RORA expression in PBMC could be a potential marker for ASD screening.

Hong Yu, Yanbin Niu, Guohua Jia et al. integrate in vitro, in vivo, and human experiments to examine a link between RORA expression on autism-like behavior. Their results suggest that maternal diabetes may contribute to autism-like behavior via RORA suppression.

Systematic review of prenatal exposure to endocrine disrupting chemicals and autism spectrum disorder in offspring

LAY ABSTRACT

Autism spectrum disorders comprise a complex group with many subtypes of behaviorally defined neurodevelopmental abnormalities in two core areas: deficits in social communication and fixated, restricted, repetitive, or stereotyped behaviors and interests each with potential unique risk factors and characteristics. The underlying mechanisms and the possible causes of autism spectrum disorder remain elusive and while increased prevalence is undoubtable, it is unclear if it is a reflection of diagnostic improvement or emerging risk factors such as endocrine disrupting chemicals. Epidemiological studies, which are used to study the relation between endocrine disrupting chemicals and autism spectrum disorder, can have inherent methodological challenges that limit the quality and strength of their findings. The objective of this work is to systematically review the treatment of these challenges and assess the quality and strength of the findings in the currently available literature. The overall quality and strength were "moderate" and "limited," respectively. Risk of bias due to the exclusion of potential confounding factors and the lack of accuracy of exposure assessment methods were the most prevalent. The omnipresence of endocrine disrupting chemicals and the biological plausibility of the association between prenatal exposure and later development of autism spectrum disorder highlight the need to carry out well-designed epidemiological studies that overcome the methodological challenges observed in the currently available literature in order to be able to inform public policy to prevent exposure to these potentially harmful chemicals and aid in the establishment of predictor variables to facilitate early diagnosis of autism spectrum disorder and improve long-term outcomes.

Prenatal Progestin Exposure-Mediated Oxytocin Suppression Contributes to Social Deficits in Mouse Offspring

Epidemiological studies have shown that maternal hormone exposure is associated with autism spectrum disorders (ASD). The hormone oxytocin (OXT) is a central nervous neuropeptide that plays an important role in social behaviors as well as ASD etiology, although the detailed mechanism remains largely unknown. In this study, we aim to investigate the potential role and contribution of OXT to prenatal progestin exposure-mediated mouse offspring. Our in vitro study in the hypothalamic neurons that isolated from paraventricular nuclei area of mice showed that transient progestin exposure causes persistent epigenetic changes on the OXT promoter, resulting in dissociation of estrogen receptor β (ERβ) and retinoic acid-related orphan receptor α (RORA) from the OXT promoter with subsequent persistent OXT suppression. Our in vivo study showed that prenatal exposure of medroxyprogesterone acetate (MPA) triggers social deficits in mouse offspring; prenatal OXT deficiency in OXT knockdown mouse partly mimics, while postnatal ERβ expression or postnatal OXT peptide injection partly ameliorates, prenatal MPA exposure-mediated social deficits, which include impaired social interaction and social abilities. On the other hand, OXT had no effect on prenatal MPA exposure-mediated anxiety-like behaviors. We conclude that prenatal MPA exposure-mediated oxytocin suppression contributes to social deficits in mouse offspring.

Why not try to predict autism spectrum disorder with crucial biomarkers in cuproptosis signaling pathway?

The exact pathogenesis of autism spectrum disorder (ASD) is still unclear, yet some potential mechanisms may not have been evaluated before. Cuproptosis is a novel form of regulated cell death reported this year, and no study has reported the relationship between ASD and cuproptosis. This study aimed to identify ASD in suspected patients early using machine learning models based on biomarkers of the cuproptosis pathway. We collected gene expression profiles from brain samples from ASD model mice and blood samples from humans with ASD, selected crucial genes in the cuproptosis signaling pathway, and then analysed these genes with different machine learning models. The accuracy, sensitivity, specificity, and areas under the receiver operating characteristic curves of the machine learning models were estimated in the training, internal validation, and external validation cohorts. Differences between models were determined with Bonferroni's test. The results of screening with the Boruta algorithm showed that FDX1, DLAT, LIAS, and ATP7B were crucial genes in the cuproptosis signaling pathway for ASD. All selected genes and corresponding proteins were also expressed in the human brain. The k-nearest neighbor, support vector machine and random forest models could identify approximately 72% of patients with ASD. The artificial neural network (ANN) model was the most suitable for the present data because the accuracy, sensitivity, and specificity were 0.90, 1.00, and 0.80, respectively, in the external validation cohort. Thus, we first report the prediction of ASD in suspected patients with machine learning methods based on crucial biomarkers in the cuproptosis signaling pathway, and these findings may contribute to investigations of the potential pathogenesis and early identification of ASD.

Autism-Related Transcription Factors Underlying the Sex-Specific Effects of Prenatal Bisphenol A Exposure on Transcriptome-Interactome Profiles in the Offspring Prefrontal Cortex

Bisphenol A (BPA) is an environmental risk factor for autism spectrum disorder (ASD). BPA exposure dysregulates ASD-related genes in the hippocampus and neurological functions of offspring. However, whether prenatal BPA exposure has an impact on genes in the prefrontal cortex, another brain region highly implicated in ASD, and through what mechanisms have not been investigated. Here, we demonstrated that prenatal BPA exposure disrupts the transcriptome-interactome profiles of the prefrontal cortex of neonatal rats. Interestingly, the list of BPA-responsive genes was significantly enriched with known ASD candidate genes, as well as genes that were dysregulated in the postmortem brain tissues of ASD cases from multiple independent studies. Moreover, several differentially expressed genes in the offspring's prefrontal cortex were the targets of ASD-related transcription factors, including AR, ESR1, and RORA. The hypergeometric distribution analysis revealed that BPA may regulate the expression of such genes through these transcription factors in a sex-dependent manner. The molecular docking analysis of BPA and ASD-related transcription factors revealed novel potential targets of BPA, including RORA, SOX5, TCF4, and YY1. Our findings indicated that prenatal BPA exposure disrupts ASD-related genes in the offspring's prefrontal cortex and may increase the risk of ASD through sex-dependent molecular mechanisms, which should be investigated further.

Paracetamol use during pregnancy - a call for precautionary action

Paracetamol (N-acetyl-p-aminophenol (APAP), otherwise known as acetaminophen) is the active ingredient in more than 600 medications used to relieve mild to moderate pain and reduce fever. APAP is widely used by pregnant women as governmental agencies, including the FDA and EMA, have long considered APAP appropriate for use during pregnancy when used as directed. However, increasing experimental and epidemiological research suggests that prenatal exposure to APAP might alter fetal development, which could increase the risks of some neurodevelopmental, reproductive and urogenital disorders. Here we summarize this evidence and call for precautionary action through a focused research effort and by increasing awareness among health professionals and pregnant women. APAP is an important medication and alternatives for treatment of high fever and severe pain are limited. We recommend that pregnant women should be cautioned at the beginning of pregnancy to: forego APAP unless its use is medically indicated; consult with a physician or pharmacist if they are uncertain whether use is indicated and before using on a long-term basis; and minimize exposure by using the lowest effective dose for the shortest possible time. We suggest specific actions to implement these recommendations. This Consensus Statement reflects our concerns and is currently supported by 91 scientists, clinicians and public health professionals from across the globe.

Neuroligin 1 expression is linked to plasticity of behavioral and neuronal responses to sex pheromone in the male moth Agrotis ipsilon

In the moth Agrotis ipsilon, the behavioral response of males to the female-emitted sex pheromone increases throughout adult life and following a prior exposure to sex pheromone, whereas it is temporally inhibited after the onset of mating. This behavioral flexibility is paralleled with changes in neuronal sensitivity to pheromone signal within the primary olfactory centers, the antennal lobes. In the present study, we tested the hypothesis that neuroligins, post-synaptic transmembrane proteins known to act as mediators of neuronal remodeling, are involved in the olfactory modulation in A. ipsilon males. We cloned a full-length cDNA encoding neuroligin 1, which is expressed predominantly in brain and especially in antennal lobes. The level of neuroligin 1 expression in antennal lobes gradually raised from day-2 until day-4 of adult life, as well as at 24 h, 48 h and 72 h following pre-exposure to sex pheromone, and the temporal dynamic of these changes correlated with increased sex pheromone responsiveness. By contrast, there was no significant variation in antennal lobe neuroligin 1 expression during the post-mating refractory period. Taken together, these results highlight that age- and odor experience-related increase in sex pheromone responsiveness is linked to the overexpression of neuroligin 1 in antennal lobes, thus suggesting a potential role played by this post-synaptic cell-adhesion molecule in mediating the plasticity of the central olfactory system in A. ipsilon.

A systematic review and meta-analysis of the association between maternal polycystic ovary syndrome and neuropsychiatric disorders in children

There is emerging evidence demonstrating an association between maternal polycystic ovary syndrome (PCOS) and autism spectrum disorder (ASD) in children, however, the cumulative effect of maternal PCOS on the development of ASD or other neuropsychiatry disorders (NPD) in children and separately for males and females has not been examined. We sought to systematically evaluate the influence of maternal PCOS on a wide range of NPD including ASD, attention deficit hyperactivity disorder (ADHD), chronic tic disorder (CDT), other behavior disorders, anxiety, depression, bipolar disorder, schizophrenia in children as well as in women of reproductive age only. We queried electronic databases including PubMed, EMBASE, and Google Scholar, until March 2021. We used DerSimonian and Laird (D-L) random effects method to compute pooled effect size in terms of odds ratio (OR). Nineteen studies (1667851 mothers, 2260622 children) were included in this study. Mothers with PCOS had an increased odds of children diagnosed with ASD (OR = 1.40, p < 0.001), ADHD (OR = 1.42, p < 0.001), CTD (OR = 1.44, p = 0.001), anxiety (OR = 1.33, p < 0.001), as well as other behavioral symptoms (OR = 1.45, p < 0.001) in the adjusted analysis. The association between maternal PCOS and ASD (OR: 1.43 vs. 1.66), ADHD (OR: 1.39 vs. 1.54), and CTD (OR: 1.42 vs. 1.51) was found to be significantly consistent between males and females, respectively. Our data do not suggest increased fetal testosterone exposure is associated with increased autistic traits in children. However, PCOS was significantly associated with increased odds of a wide range of NPD in women themselves. Maternal PCOS is a risk factor for various NPD with a similar extent in their children regardless of their underlying comorbidities. Managing PCOS is essential for women's health as well as for their children's health. More research is needed to determine the mechanisms and links between maternal PCOS and NPD in children.

Placental endocrine function shapes cerebellar development and social behavior

Compromised placental function or premature loss has been linked to diverse neurodevelopmental disorders. Here we show that placenta allopregnanolone (ALLO), a progesterone-derived GABA-A receptor (GABA_AR) modulator, reduction alters neurodevelopment in a sex-linked manner. A new conditional mouse model, in which the gene encoding ALLO's synthetic enzyme (akr1c14) is specifically deleted in trophoblasts, directly demonstrated that placental ALLO insufficiency led to cerebellar white matter abnormalities that correlated with autistic-like behavior only in male offspring. A single injection of ALLO or muscimol, a GABA_AR agonist, during late gestation abolished these alterations. Comparison of male and female human preterm infant cerebellum also showed sex-linked myelination marker alteration, suggesting similarities between mouse placental ALLO insufficiency and human preterm brain development. This study reveals a new role for a placental hormone in shaping brain regions and behaviors in a sex-linked manner. Placental hormone replacement might offer novel therapeutic opportunities to prevent later neurobehavioral disorders.

Prenatal Exposure to Diethylstilbestrol and Multigenerational Psychiatric Disorders: An Informative Family

BACKGROUND

Psychiatric disorders in children exposed in utero to diethylstilbestrol (DES) are still debated. We report here the impact of DES prescribed to suppress lactation on the children born after such treatment and their progeny, focusing particularly on psychiatric disorders.

CASE PRESENTATION

We report here an informative family in which one or more psychiatric problems (e.g., bipolarity, suicide attempts and suicide, eating disorders) were detected in all children of second-generation (DES-exposed children; n = 9), but for II-2 who died at the age of 26 years due to rupture of a congenital brain aneurysm, and were associated with non-psychiatric disorders (particularly, endometriosis and hypospadias). In the third generation, 10 out of 19 DES-exposed grandchildren had psychiatric disorders (autism spectrum disorder, bipolar disorder, dyspraxia and learning disabilities, mood and behavioral disorders, and eating disorders), often associated with comorbidities. In the fourth generation (7 DES-exposed great-grandchildren, aged between 0 and 18 years), one child had dyspraxia and autism spectrum disorder. The first daughter of the second generation (not exposed to DES) and her children and grandchildren did not have any psychiatric symptoms or comorbidities.

CONCLUSIONS

To our knowledge, the high prevalence of psychiatric disorders of various severities in two, and likely three generations, including DES-free pregnancies and DES-exposed pregnancies from the same family, has never been reported. This work strengthens the hypothesis that in utero exposure to DES contributes to the pathogenesis of psychiatric disorders. It also highlights a multigenerational, and possibly transgenerational, effect of DES in neurodevelopment and psychiatric disorders.

Atypical Brain Asymmetry in Autism-A Candidate for Clinically Meaningful Stratification

BACKGROUND

Autism spectrum disorder ("autism") is a highly heterogeneous neurodevelopmental condition with few effective treatments for core and associated features. To make progress we need to both identify and validate neural markers that help to parse heterogeneity to tailor therapies to specific neurobiological profiles. Atypical hemispheric lateralization is a stable feature across studies in autism, but its potential as a neural stratification marker has not been widely examined.

METHODS

In order to dissect heterogeneity in lateralization in autism, we used the large EU-AIMS (European Autism Interventions-A Multicentre Study for Developing New Medications) Longitudinal European Autism Project dataset comprising 352 individuals with autism and 233 neurotypical control subjects as well as a replication dataset from ABIDE (Autism Brain Imaging Data Exchange) (513 individuals with autism, 691 neurotypical subjects) using a promising approach that moves beyond mean group comparisons. We derived gray matter voxelwise laterality values for each subject and modeled individual deviations from the normative pattern of brain laterality across age using normative modeling.

RESULTS

Individuals with autism had highly individualized patterns of both extreme right- and leftward deviations, particularly in language, motor, and visuospatial regions, associated with symptom severity. Language delay explained most variance in extreme rightward patterns, whereas core autism symptom severity explained most variance in extreme leftward patterns. Follow-up analyses showed that a stepwise pattern emerged, with individuals with autism with language delay showing more pronounced rightward deviations than individuals with autism without language delay.

CONCLUSIONS

Our analyses corroborate the need for novel (dimensional) approaches to delineate the heterogeneous neuroanatomy in autism and indicate that atypical lateralization may constitute a neurophenotype for clinically meaningful stratification in autism.