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Murgatroyd, C.

Publications and source records attributed to Murgatroyd, C..

6 recordsLinked to original sources

Regional alignment with sex-typical brain architecture, maternal health and environmental enrichment predict psychiatric symptoms in early life

Robust sex differences in brain morphology and function exist from birth onwards. While traditionally conceptualized as categorical, they were recently shown to be best described along a female-to-male continuum. Here, we probed the under-explored implications of this proposal for understanding early life vulnerability to psychiatric conditions with sex-biased prevalence. We analyzed environmental, clinical and resting state functional neuroimaging data from 411 participants in Developing Human Connectome Project (dHCP) and 214 children from the Oregon ADHD 1000 study. In the dHCP, we identified complementary patterns of neonatal alignment with sex-typical young adult architecture, which overlapped areas rich in nicotinic cholinergic receptors and predicted the same psychiatric symptoms across sexes in toddlerhood. Specifically, for association (compared to sensorimotor) areas, greater alignment with female-typical functional connectivity (FC) patterns foreshadowed higher anxiety, whereas greater alignment with male-typical FC patterns forecasted autism-related problems. The latter effect was weaker among toddlers with an older epigenetic age at birth and exposure to fewer maternal health problems, but greater environmental enrichment. In the independent child sample, patterns of alignment with sex-typical FC, overlapping those observed in neonates, distinguished a history of depression and generalized anxiety (greater alignment with female-typical FC) from a history of separation anxiety, behavioral problems and current ADHD (greater alignment with male-typical FC). Our study speaks to the psychiatric relevance of sex-related functional brain architecture from birth onwards, its value in identifying vulnerable youths and its promise in monitoring the success of environmental interventions.

neuroscience↗

The obesity associated BDNF intron-3 cis-regulatory element, BE5.1, modulates the effects of early-life stress on weight gain, anxiety and gene expression in a sex dependent manner.

Early-life stress (ELS) has been associated with increases in obesity and anxiety and affects males and females in different ways. Animal and human studies indicate that ELS has maladaptive effects on brain development due, in part, to disruptions in the expression of genes that include brain-derived neurotrophic factor (BDNF). Our previous studies identified a cis-regulatory element (CRE, BE5.1) within BDNF intron-3 that harbours a SNP associated with obesity and anxiety. We used maternal separation (MS) to examine the role of BE5.1 in controlling resilience to the maladaptive effects of ELS. At 9-11 weeks, BE5.1KO mice experience a delay in weight gain compared to WT mice, a phenotype partly reversed by MS in BE5.1KO females. The effects of either MS or BE5.1KO decreased anxiety-like behaviour in males whereas MS had little effect in females who displayed increased anxiety-like behaviour in animals lacking BE5.1. We also found that social behaviours are influenced by BE5.1 deletion in females but are more influenced by MS in males. Furthermore, deletion of BE5.1 and MS together significantly decreased marble burying behaviour in male mice, an effect negated by diazepam. RNA-seq analyses suggest that, in hypothalamus, BE5.1 is required to stabilize or down-regulate the transcription of 26 key genes, with diverse neuroregulatory roles, in response to MS as these 26 genes are strongly upregulated in the absence of BE5.1. We also provide evidence that three of these genes; Prkcg, Foxg1 and Mef2c, modulate BE5.1 activity in an allele-specific manner. Taken together, these results suggest that the BE5.1CRE acts as a buffer element that protects against the maladaptive effects of MS on gene expression and later life behaviours in a sex-dependent manner.

molecular biology↗

SKA2 regulated hyperactive secretory autophagy drives neuroinflammation-induced neurodegeneration

High levels of proinflammatory cytokines induce neurotoxicity and catalyze inflammation-driven neurodegeneration, but the specific release mechanisms from microglia remain elusive. We demonstrate that secretory autophagy (SA), a non-lytic modality of autophagy for secretion of vesicular cargo, regulates neuroinflammation-mediated neurodegeneration via SKA2 and FKBP5 signaling. SKA2 inhibits SA-dependent IL-1{beta} release by counteracting FKBP5 function. Hippocampal Ska2 knockdown in mice hyperactivates SA resulting in neuroinflammation, subsequent neurodegeneration and complete hippocampal atrophy within six weeks. The hyperactivation of SA increases IL-1{beta} release, initiating an inflammatory feed-forward vicious cycle including NLRP3-inflammasome activation and Gasdermin D (GSDMD)-mediated neurotoxicity, which ultimately drives neurodegeneration. Results from protein expression and co-immunoprecipitation analyses of postmortem brains demonstrate that SA is hyperactivated in Alzheimers disease. Overall, our findings suggest that SKA2-regulated, hyperactive SA facilitates neuroinflammation and is linked to Alzheimers disease, providing new mechanistic insight into the biology of neuroinflammation.

neuroscience↗

CRISPR disruption and UK Biobank analysis of a highly conserved polymorphic enhancer suggests its role in anxiety and male alcohol intake.

Excessive alcohol intake is associated with 5.9% of global deaths. However, this figure is especially acute in men such that 7.6% of deaths can be attributed to alcohol intake. Previous studies identified a significant interaction between genotypes of the galanin (GAL) gene with anxiety and alcohol abuse in different male populations but were unable to define a mechanism. To address these issues the current study analysed the human UK Biobank cohort and identified a significant interaction (n=115,865; p=0.0007) between allelic variation (GG or CA genotypes) in the highly conserved human GAL5.1 enhancer, alcohol intake (AUDIT questionnaire scores) and anxiety in men that was consistent with these previous studies. Critically, disruption of GAL5.1 in mice using CRISPR genome editing significantly reduced GAL expression in the amygdala and hypothalamus whilst producing a corresponding reduction in ethanol intake in KO mice. Intriguingly, we also found evidence of reduced anxiety-like behaviour in male GAL5.1KO animals mirroring that seen in humans. Using bioinformatic analysis and co-transfection studies we further identified the EGR1 transcription factor, that is co expressed with GAL in amygdala and hypothalamus, as being important in the protein kinase C (PKC) supported activity of the GG genotype of GAL5.1 but less so in the CA genotype. Our unique study uses a novel combination of human association analysis, CRISPR genome editing in mice, animal behavioural analysis and cell culture studies to identify a highly conserved regulatory mechanism linking anxiety and alcohol intake that might contribute to increased susceptibility to anxiety and alcohol abuse in men.

genetics↗

Discrimination Exposure and DNA Methylation of Stress-Related Genes in Latina Mothers

Latina mothers, who have the highest fertility rate among all ethnic groups in the US, are often exposed to discrimination. The biological impacts of this discrimination are unknown. This study is the first to explore the relationship between discrimination and DNA methylation of stress regulatory genes in Latinas. Our sample was Latina women (n = 147) with a mean age of 27.6 years who were assessed at 24-32 weeks gestation (T1) and 4-6 weeks postpartum (T2) and reside in the U.S. Blood was collected at T1, and the Everyday Discrimination Scale (EDS) was administered at T1 and T2. DNA Methylation at candidate gene regions was determined by bisulphite pyrosequencing. Associations between EDS and DNA methylation were assessed via zero-inflated Poisson models, adjusting for covariates and multiple-test comparisons. Discrimination was negatively associated with methylation at CpG sites within the glucocorticoid receptor (NR3C1) and brain-derived neurotrophic factor (BDNF) genes that were consistent over time. In addition, discrimination was negatively associated with methylation of a CpG in the glucocorticoid binding protein (FKBP5) at T1 but not at T2. This study underscores the complex biological pathways between discrimination and epigenetic modification in Latina women that warrant further investigation to better understand the genetic and psychopathological impact of discrimination on Latino mothers and their families.

genomics↗

Maternal depression and child behaviours: sex-dependent mediation by glucocorticoid receptor gene methylation in a longitudinal study from pregnancy to age 5 years

BackgroundEvolutionary hypotheses predict that male fetuses are more vulnerable to poor maternal conditions than females (Sex-biased Maternal Investment), but that the adaptive female fetus, with a more responsive hypothalamic-pituitary-adrenal (HPA) axis, is put at later risk of glucocorticoid mediated disorders where there is a mismatch between fetal and postnatal environments (Predictive Adaptive Response). Self-report measures of prenatal and postnatal depression and maternal report of child anxious depressed symptoms at 2.5, 3.5 and 5.0 years were obtained from an extensive sample of first time mothers recruited from the general population (N = 794). Salivary NR3C1 1-F promoter methylation was assayed at 14 months in an intensive subsample (N = 176) stratified during pregnancy by psychosocial risk. Generalised structural equation models (SEM) were fitted and estimated by maximum likelihood to allow inclusion of participants from both intensive and extensive samples.\n\nResultsPostnatal depression was associated with NR3C1 methylation and with anxious-depressed symptoms in the daughters of mothers lacking the hypothesised protective effect of high prenatal depression (prenatal-postnatal depression interaction for methylation, p =.00001; for child symptoms, p = .011). In girls, NR3C1 methylation mediated the association between maternal depression and child anxious-depressed symptoms. The effects were greater in girls than boys, and the test of the sex differences in the effect of the prenatal-postnatal depression interaction on both outcomes gave {chi}2(2) = 5.95 (p=.051).\n\nConclusionsThis is the first study to show in humans that, as a result of sex-biased reproductive investment and fetal adaptation, epigenetic and early behavioural outcomes may arise through different mechanisms in males and females. Epigenetic effects at the NR3C1 promoter mediated mismatch between prenatal and postnatal maternal conditions and child anxious-depressed symptoms, specifically in females.

genetics↗