Marked Sex Differences Research Articles

Evaluation of Health Associations With Height-Normalised Abdominal Body Composition Indices: A Single-Centre Cross-Sectional Study.

Traditional metrics such as body mass index (BMI) and waist circumference (WC) fail to accurately assess the health outcomes associated with abdominal adiposity, because they neglect the intricacies of adipose tissue distribution. Notably, the variability in body composition scaled to height remains underexplored in Chinese demographics. This study introduces height-normalised indices of abdominal adiposity using computed tomography (CT) scans and further assesses their associations with various health outcomes. In a large, diverse Chinese population (n = 1054 healthy individuals; n = 1159 with dyslipidemia; n = 803 with diabetes; n = 1289 with cardio-cerebrovascular diseases; n = 1108 with cancers; and n = 509 with abnormal bone mas), abdominal CT scans were performed and allometric growth model analyses were used to derive height-normalised indices (body composition/heightβ). Logistic regression models assessed the associations between these indices and health outcomes. Distinct scaling powers were observed for visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and total abdominal adipose tissue (TAT), as well as for sagittal diameter (SAD), with marked sex differences. Powers for VAT were 1.786 ± 1.270 for males and 1.274 ± 0.692 for females. Powers for SAT were 2.266 ± 0.856 for males and 1.656 ± 0.497 for females. Powers for TAT were 2.141 ± 0.967 for males and 1.438 ± 0.489 for females. Powers for SAD were 0.646 ± 0.217 for males and 0.678 ± 0.141 for females. After controlling for age, BMI and WC, VAT/heightβ, TAT/heightβ and SAD/heightβ retained their significantly positive associations with the odds of health outcomes, whereas SAT/heightβ did not. Our findings endorse the clinical utility of height-normalised indices, particularly VAT/heightβ, TAT/heightβ and SAD/heightβ, in health outcomes assessment. These indices, grounded in robust empirical data, underscore the necessity of a nuanced approach in obesity-related health evaluations, advocating for a departure from conventional methods like BMI.

6681 Age and Sex Disparity in NASH and the Potential Role of Estradiol Treatment for NASH

Abstract Disclosure: M. Tripathi: None. S. Sakthivel: None. A. Suzuki: None. B.K. Singh: None. P.M. Yen: None. Introduction: NAFLD (nonalcoholic fatty liver disease) and its more severe form, NASH (nonalcoholic steatohepatitis) are sexually dimorphic conditions that exhibit higher prevalence in men than women during reproductive ages but have similar prevalence after menopause. Reproductive age women are protected from hepatic fibrosis relative to men, although they lose this protection after menopause. These sex differences in NASH have been attributed, at least partly, to different circulating estrogen levels. However, the underlying mechanism(s) is not fully understood. We thus conducted animal experiments to investigate: 1) sex differences in the histologic severity of NASH, necroinflammatory and fibrogenic activities, and other relevant pathways in young and old male and female mice and 2) the effects of estradiol administration on these parameters in old male and female mice to evaluate the therapeutic potential of estradiol in NASH. Methodology: Young/reproductive age (12-weeks old) and old/post-reproductive age female and male (48∼50-weeks weeks old) C57BL/6J mice were fed control chow diet (NCD) or high-fat methionine/choline-deficient (MCD) diet for six weeks to induce NASH. The old mice were administered 200nM 17β-estradiol (physiological) in drinking water. We analyzed serum and hepatic NASH parameters, ER stress, and lysosome-autophagy defects. Results and Conclusion: Among reproductive age mice with NASH, females developed less severe histologic inflammation and fibrosis and decreased gene expression of Il1b, Il6, Tgfb, Col1a1, Ccl2, and Ccl5, and lower hepatic collagen than males. Females with NASH also had less inhibition of hepatic autophagy and lysosomal protein expression than males with NASH. Among old mice, post-reproductive age females fed NCD or MCD exhibited more severe hepatic inflammation and fibrosis and had higher gene expression of inflammatory and fibrogenic markers with comparable autophagic inhibition and lysosomal defects as similar age males. Physiological doses of estradiol significantly reduced hepatic gene expression of inflammatory and fibrogenic markers, ER stress and lysosomal-autophagic defects in post-reproductive age females. In conclusion, similar to clinical NASH, we observed marked sex and age-related differences in the severity of NASH. Furthermore, physiological doses of estradiol treatment improved the hepatic histology, lysosome-autophagy, inflammation, and fibrosis in post-reproductive age female mice with NASH and suggests that estradiol supplementation may decrease or reverse NASH progression in post-menopausal women with NASH. Presentation: 6/2/2024

Cluster B personality disorders and psychotropic medications: a focused analysis of trends and patterns across sex and age groups.

This study investigated sex and age differences in patterns of psychotropic medication use before and after the initial diagnosis of Cluster B personality disorders (PDs) and analyzed trends over time. Analyzing data from the Quebec Integrated Chronic Disease Surveillance System for individuals newly diagnosed with Cluster B PD (≥ 14 years) between 2002 and 2018 and under the provincial public drug plan, we calculated yearly and monthly proportions of individuals exposed to psychotropic medications during the year before and after their diagnosis by sex and age. Robust Poisson regression models assessed the association between sex and exposure to psychotropic medications after the diagnosis of Cluster B PD. Among 87,778 individuals with a first Cluster B PD diagnosis (mean age: 44.5 years; 57.5% women), the proportion of users increased post-diagnosis. Notably, after diagnosis, females were more likely to receive psychiatric medications (between 78.9% and 83.7% during the study period vs. 72.8% and 76.8%). Males were less likely than females to receive antidepressants (adjusted prevalence ratio (aPR): 0.83; 99% confidence interval (CI): 0.82-0.85) and anxiolytics (aPR: 0.86; 99%CI: 0.84-0.88), whereas they had higher exposure to antipsychotics (aPR: 1.04; 99%CI: 1.02-1.06) and ADHD medications (aPR: 1.14; 99%CI: 1.07-1.2). Age-specific trends showed increased ADHD medication use among younger patients (14-24 years), and anxiolytic use predominated in those aged ≥ 65 years. Psychotropic medication use was high among Cluster B PD patients, with differences in medication classes according to age and sex. The marked sex and age differences in psychotropic medication use among Cluster B PD patients underscore the need for a sex-sensitive and age-specific approach in psychiatric care.

IGF-1 induces sex-specific oxidative damage and mortality in a songbird

The insulin-like growth factor 1 (IGF-1) is a pleiotropic hormone that regulates essential life-history traits and is known for its major contribution to determining individual ageing processes. High levels of IGF-1 have been linked to increased mortality and are hypothesised to cause oxidative stress. This effect has been observed in laboratory animals, but whether it pertains to wild vertebrates has not been tested. This is surprising because studying the mechanisms that shape individual differences in lifespan is important to understanding mortality patterns in populations of free-living animals. We tested this hypothesis under semi-natural conditions by simulating elevated IGF-1 levels in captive bearded reedlings, a songbird species with an exceptionally fast pace of life. We subcutaneously injected slow-release biodegradable microspheres loaded with IGF-1 and achieved a systemic 3.7-fold increase of the hormone within the natural range for at least 24 h. Oxidative damage to lipids showed marked sexual differences: it significantly increased the day after the manipulation in treated males and returned to baseline levels four days post-treatment, while no treatment effect was apparent in females. Although there was no overall difference in survival between the treatment groups, high initial (pre-treatment) IGF-1 and low post-treatment plasma malondialdehyde levels were associated with enhanced survival prospects in males. These results suggest that males may be more susceptible to IGF-1-induced oxidative stress than females and quickly restoring oxidative balance may be related to fitness. IGF-1 levels evolve under opposing selection forces, and natural variation in this hormone’s level may reflect the outcome of individual optimization.

Sex differences in the distribution and density of regulatory interneurons in the striatum.

Dysfunction of the cortico-basal circuitry - including its primary input nucleus, the striatum - contributes to neuropsychiatric disorders, such as autism and Tourette Syndrome (TS). These conditions show marked sex differences, occurring more often in males than in females. Regulatory interneurons, such as cholinergic interneurons (CINs) and parvalbumin-expressing GABAergic fast spiking interneurons (FSIs), are implicated in human neuropsychiatric disorders such as TS, and ablation of these interneurons produces relevant behavioral pathology in male mice, but not in females. Here we investigate sex differences in the density and distribution of striatal interneurons. We use stereological quantification of CINs, FSIs, and somatostatin-expressing (SOM) GABAergic interneurons in the dorsal striatum (caudate-putamen) and the ventral striatum (nucleus accumbens) in male and female mice. Males have a higher density of CINs than females, especially in the dorsal striatum; females have equal distribution between dorsal and ventral striatum. FSIs showed similar distributions, with a greater dorsal-ventral density gradient in males than in females. SOM interneurons were denser in the ventral than in the dorsal striatum, with no sex differences. These sex differences in the density and distribution of FSIs and CINs may contribute to sex differences in basal ganglia function, particularly in the context of psychopathology.

Incidence and prevalence of primary biliary cholangitis in the Netherlands – A nationwide cohort study

Background & AimsAlthough primary biliary cholangitis (PBC) is considered a rare disorder, accurate determination of its incidence and prevalence remains challenging due to limited comprehensive population-based registries. We aimed to assess the incidence and prevalence of PBC in the Netherlands over time through the nation-wide Dutch PBC Cohort Study (DPCS). MethodsDPCS included retrospectively every identifiable patient with PBC in the Netherlands from 1990 onwards in all 71 Dutch hospitals. Incidence and prevalence were assessed between 2008-2018 by Poisson regression between sex and age groups over time. ResultsOn January 1st 2008, there were 1458 patients with PBC in the Netherlands. Between 2008-2018, 2187 individuals were newly diagnosed, 46 were transplanted and 468 died. The yearly incidence of PBC in 2008 was 1.38, and increased to 1.74 per 100.000 persons in 2018. When compared to those aged <45 years, females aged 45-64 years (adjusted Incidence Rate Ratio [aIRR] 4.21, 95%CI 3.76-4.71, p<0.001) and males ≥65 years (aIRR 14.41, 95%CI 9.62-21.60, p<0.001) had the highest risk to be diagnosed with PBC. The male-to-female ratio of patients newly diagnosed with PBC during the study period was 1:14 in those <45 years, 1:10 in patients aged 45-64 years, and 1:4 in those ≥65 years. Point prevalence increased from 11.9 in 2008 to 21.5 per 100.000 persons in 2018. Average annual percent change (AAPC) in this time period was 5.94% (95%CI 5.77-6.15, p<0.05), and was the highest among the population ≥65 years (5.69%, 95%CI 5.32-6.36, p<0.001). ConclusionsIn this nationwide cohort study, we observed an increase in both incidence and prevalence of PBC in the Netherlands over the past decade, with marked age and sex differences. Impact And ImplicationsThis nationwide Dutch PBC cohort study, including all hospitals in the Netherlands, showed that the PBC incidence and prevalence has increased over the last decade. The age-dependent PBC incidence rate differed for males (highest risk ≥65 years) and females (highest risk between 45 and 65 years), which may be related to a difference in the timing of exposure to environmental triggers of PBC. The largest increase in PBC prevalence over time was observed in the population ≥65 years, which may have implications for the use of second line therapies. These results therefore indicate that further studies are needed to elaborate on the advantages and disadvantages of add-on therapies in the elderly population.

Sex-specific effects of dietary restriction on physiological variables in Japanese quails.

Nutritional limitation is a common phenomenon in nature that leads to trade-offs among processes competing for limited resources. These trade-offs are mediated by changes in physiological traits such as growth factors and circulating lipids. However, studies addressing the sex-specific effect of nutritional deficiency on these physiological variables are limited in birds. We used dietary restriction to mimic the depletion of resources to various degrees and investigated sex-specific effects on circulating levels of insulin-like growth factor 1 (IGF-1) and triglycerides in Japanese quails (Coturnix japonica) subjected to adlibitum, 20%, 30% or 40% restriction of their daily requirement, for 2 weeks. We also explored the association of both physiological variables with body mass and egg production. While dietary restriction showed no effects on circulating IGF-1, this hormone exhibited a marked sexual difference, with females having 64.7% higher IGF-1 levels than males. Dietary restriction significantly reduced plasma triglyceride levels in both sexes. Females showed more than six-fold higher triglyceride levels than males. Triglyceride levels were positively associated with body mass in females while showed not association in males. Overall, our findings revealed sex-specific expression of physiological variables under dietary restriction conditions, which coincide with body size.

Sex differences in muscle morphology between male and female sprinters.

There is a marked difference between males and females in sprint running performance, yet a comprehensive investigation of sex differences in the muscle morphology of sprinters, which could explain the performance differences, remains to be completed. This study compared muscle volumes of 23 individual leg muscles and 5 functional muscle groups, assessed with 3 T magnetic resonance imaging, between male (n = 31) and female (n = 22) sprinters, as well as subgroups of elite males (EM, n = 5), elite females (EF, n = 5), and performance-matched (to elite females) males (PMMEF, n = 6). Differences in muscle volume distribution between EM, EF, and unathletic male (UM) controls were also assessed. For the full cohorts, male sprinters were more muscular than their female counterparts, but the differences were nonuniform and anatomically variable, with the largest differences in the hip extensors and flexors. However, among elite sprinters the sex differences in the volume of the functional muscle groups were almost uniform (absolute volume +47-53%), and the muscle volume distribution of EM was more similar to EF than to UM (P < 0.039). For PMMEF, relative hip extensor volume, but not stature or percent body fat, differentiated for performance (PMMEF and EF < EM) rather than sex. In conclusion, although the full cohorts of sprinters showed a marked sex difference in the amount and distribution of muscle mass, elite sprinters appeared to be selected for a common muscle distribution phenotype that for these elite subgroups was a stronger effect than that of sex. Relative hip extensor muscle volume, rather than stature, percent body fat, or total relative muscle volume, appeared to be the primary determinant of the sex difference in performance.NEW & NOTEWORTHY We present novel evidence suggesting muscle volume, specifically relative hip extensor volume, may be a primary deterministic variable for the sex difference in sprint performance, such that with matched sprint times, male and female sprinters may be expected to have equivalent muscle morphology. We highlight striking similarities in distribution of leg muscle mass between elite male and female sprinters and provide evidence for the existence of a muscular distribution phenotype specific to elite sprinters, irrespective of sex.

Psychosocial distress and health status as risk factors for ten-year major adverse cardiac events and mortality in patients with non-obstructive coronary artery disease

BackgroundWe examined the risk of psychosocial distress, including Type D personality, depressive symptoms, anxiety, positive mood, hostility, and health status fatigue and disease specific and generic quality of life for MACE in patients with non-obstructive coronary artery disease (NOCAD). MethodsIn the Tweesteden mild stenosis (TWIST) study, 546 patients with NOCAD were followed for 10 years to examine the occurrence of cardiac mortality, a major cardiac event, or non-cardiac mortality in the absence of a cardiac event. Cox proportional hazard models were used to examine the impact of psychosocial distress and health status on the occurrence of MACE while adjusting for age, sex, disease severity, and lifestyle covariates. ResultsIn total 19% of the patients (mean age baseline = 61, SD 9 years; 52% women) experienced MACE, with a lower risk for women compared to men. Positive mood (HR 0.97, 95%CI 0.95–1.00), fatigue (HR 1.03, 95%CI 1.00–1.06), and physical limitation (HR 0.99, 95%CI 0.98–1.00) were associated with MACE in adjusted models. No significant interactions between sex and psychosocial factors were present. Depressive symptoms were predictive of MACE, but no longer after adjustment. ConclusionsIn patients with NOCAD fatigue, low positive mood, and a lower physical limitation score were associated with MACE, without marked sex differences. Type D personality, psychosocial factors, and health status were not predictive of adverse outcomes. Reducing psychosocial distress is a valid intervention goal by itself, though it is less likely to affect MACE in patients with NOCAD.

Predicting sex differences in the effects of diuretics in renal epithelial transport during angiotensin II-induced hypertension.

Chronic angiotensin II (ANG II) infusion is an experimental model that induces hypertension in rodents. The natriuresis, diuresis, and blood pressure responses differ between males and females. This is perhaps not unexpected, given the rodent kidney, which plays a key role in blood pressure regulation, exhibits marked sex differences. Under normotensive conditions, compared with males, the female rat nephron exhibits lower Na+/H+ exchanger 3 (NHE3) activity along the proximal tubule but higher Na+ transporter activities along the distal segments. ANG II infusion-induced hypertension induces a pressure natriuretic response that reduces NHE3 activity and shifts Na+ transport capacity downstream. The goals of this study were to apply a computational model of epithelial transport along a rat nephron 1) to understand how a 14-day ANG II infusion impacts segmental electrolyte transport in male and female rat nephrons and 2) to identify and explain any sex differences in the effects of loop diuretics, thiazide diuretics, and K+-sparing diuretics. Model simulations suggest that the NHE3 downregulation in the proximal tubule is a major contributor to natriuresis and diuresis in hypertension, with the effects stronger in males. All three diuretics are predicted to induce stronger natriuretic and diuretic effects under hypertension compared with normotension, with relative increases in sodium excretion higher in hypertensive females than in males. The stronger natriuretic responses can be explained by the downstream shift of Na+ transport load in hypertension and by the larger distal transport load in females, both of which limit the ability of the distal segments to further elevate their Na+ transport.NEW & NOTEWORTHY Sex differences in the prevalence of hypertension are found in human and animal models. The kidney, which regulates blood pressure, exhibits sex differences in morphology, hemodynamics, and membrane transporter distributions. This computational modeling study provides insights into how the sexually dimorphic responses to a 14-day angiotensin II infusion differentially impact segmental electrolyte transport in rats. Simulations of diuretic administration explain how the natriuretic and diuretic effects differ between normotension and hypertension and between the sexes.

Sex-specific alterations in the gut and lung microbiome of allergen-induced mice.

Recent evidence has demonstrated that the microbiome is a driver of the underlying pathophysiological mechanisms of respiratory disease. Studies have indicated that bacterial metabolites produced in the gut and lung can impact lung inflammation and immune cell activity, affecting disease pathology. Despite asthma being a disease with marked sex differences, experimental work linking microbiomes and asthma has not considered the sex variable. To test the hypothesis that the lung and gut microbial composition impacts allergic lung inflammation in a sex-specific manner, we evaluated lung and gut microbiome alterations in a mouse model of allergic inflammation and assessed their association with lung function and inflammation phenotypes. For this, we exposed male and female adult C57BL/6J mice intranasally to 25 µg of a house dust mite extract mix (HDM) daily, or phosphate-buffered saline (PBS) as control, for 5 weeks (n = 4-6/group). DNA from fecal pellets collected before and after the 5-week treatment, and from lung tissue collected at endpoint, was extracted using the ZymoBIOMICS®-96 MagBead DNA Kit and analyzed to determine the 16S microbiome via Targeted Metagenomic Sequencing. The HDM treatment induced a sex-specific allergic inflammation phenotype with significantly higher neutrophilia, lymphocytosis, inflammatory gene expression, and histopathological changes in females than males following exposure to HDM, but higher airway hyperresponsiveness (AHR) in males than females. In addition, sex-specific lung gene expression and associated pathways were identified HDM mix after challenge. These changes corresponded to sex-specific alterations in the gut microbiome, where the Firmicutes to Bacteroidetes ratio (F:B) was significantly reduced in fecal samples from only male mice after HDM challenge, and alpha diversity was increased in males, but decreased in females, after 5-weeks of HDM treatment. Overall, our findings indicate that intranasal allergen challenge triggers sex-specific changes in both gut and lung microbiomes, and induces sex-specific lung inflammation, AHR, and lung inflammatory gene expression pathways, suggesting a contribution of the lung-gut axis in allergic airway disease.

Sex and interspecies differences in ESR2-expressing cell distributions in mouse and rat brains

BackgroundESR2, a nuclear estrogen receptor also known as estrogen receptor β, is expressed in the brain and contributes to the actions of estrogen in various physiological phenomena. However, its expression profiles in the brain have long been debated because of difficulties in detecting ESR2-expressing cells. In the present study, we aimed to determine the distribution of ESR2 in rodent brains, as well as its sex and interspecies differences, using immunohistochemical detection with a well-validated anti-ESR2 antibody (PPZ0506).MethodsTo determine the expression profiles of ESR2 protein in rodent brains, whole brain sections from mice and rats of both sexes were subjected to immunostaining for ESR2. In addition, to evaluate the effects of circulating estrogen on ESR2 expression profiles, ovariectomized female mice and rats were treated with low or high doses of estrogen, and the resulting numbers of ESR2-immunopositive cells were analyzed. Welch’s t-test was used for comparisons between two groups for sex differences, and one-way analysis of variance followed by the Tukey–Kramer test were used for comparisons among multiple groups with different estrogen treatments.ResultsESR2-immunopositive cells were observed in several subregions of mouse and rat brains, including the preoptic area, extended amygdala, hypothalamus, mesencephalon, and cerebral cortex. Their distribution profiles exhibited sex and interspecies differences. In addition, low-dose estrogen treatment in ovariectomized female mice and rats tended to increase the numbers of ESR2-immunopositive cells, whereas high-dose estrogen treatment tended to decrease these numbers.ConclusionsImmunohistochemistry using the well-validated PPZ0506 antibody revealed a more localized expression of ESR2 protein in rodent brains than has previously been reported. Furthermore, there were marked sex and interspecies differences in its distribution. Our histological analyses also revealed estrogen-dependent changes in ESR2 expression levels in female brains. These findings will be helpful for understanding the ESR2-mediated actions of estrogen in the brain.

Sex specific lifetime risk of incident cardiovascular events. Results from a large British population-based cohort study

Abstract Background There are marked sex differences in cardiovascular (CV) disease, most characteristically with men having a higher risk of coronary heart disease and myocardial infarction (MI). The sex differences in the absolute lifetime risk of CV disease as well as the different profiles of first incident CV events remain poorly described. Purpose Using data from a large British population-based cohort study with long follow-up, we aimed to compare the sex differences in the lifetime risk of incident CV events (MI, stroke, atrial fibrillation (AF), heart failure (HF), peripheral artery disease (PAD) and CV mortality). Methods Eligible participants at the study baseline (1993-1998) were included and followed up until March 2018. Cause-specific hazard ratios were ascertained using Weibull regressions. The sex-specific lifetime risks of each outcome were ascertained using Weibull regressions accounting for the competing risk of death. All models were adjusted for time-updated covariates: ethnicity, Townsend index of deprivation, systolic blood pressure, hypercholesterolaemia, diabetes, smoking, alcohol intake, physical activity, body mass index, fruit/vegetable intake, non-cardiovascular conditions and medication. Results 8975 men and 11,330 women aged ≥40 and free of CV disease at baseline were included. The median follow-up was 22.3 years. Compared to women, men were more likely to be older, have higher systolic blood pressure, higher BMI and be less physically active. Men were less likely to have prevalent non-cardiovascular comorbidities. The adjusted cumulative incidence of a CV event ranged between 13.8%-28.2% for men and 7.5%-21.2% for women (Figure 1). The lifetime risk of CV mortality was 28.7% for men and 22.9% for women. Compared to women, the relative risk of incident CV events for men was two-fold higher for MI (cause specific hazard ratio (95% confidence interval) – 2.05 (1.83-2.30)) and PAD (2.02 (1.83-2.23)), 50% higher for HF (1.52 (1.39-1.66)) and AF (1.51 (1.40-1.62)), 42% for cardiovascular mortality (1.42 (1.32-1.53)) and 12% for stroke (1.12 (1.03-1.22)). There were also sex differences in the lifetime incidence of different types of first CV event (Figure 2). Amongst men, MI had the highest incidence as a first CV event throughout lifetime. The earliest incidence rise in MI occurred by 50 years and was followed by AF, PAD, stroke and heart failure over the following decades. In women, the incidence of MI as a first CV event was highest between 50-60 years but was overtaken by AF by 65 years and stroke by 70 years. Conclusions Men had a higher risk of incident cardiovascular disease throughout their lifetime than women, but these sex differences were most pronounced for MI and PAD, followed by AF, HF and CV mortality. These were also reflected in the different sex profiles characterising the type of first incident CV event. These differences highlight the importance of tailoring sex-specific primary preventative strategies.Figure 1Figure 2

The accumulation of erythrocytes quantified and visualized by Glycophorin C in carotid atherosclerotic plaque reflects intraplaque hemorrhage and pre-procedural neurological symptoms

The accumulation of erythrocyte membranes within an atherosclerotic plaque may contribute to the deposition of free cholesterol and thereby the enlargement of the necrotic core. Erythrocyte membranes can be visualized and quantified in the plaque by immunostaining for the erythrocyte marker glycophorin C. Hence, we theorized that the accumulation of erythrocytes quantified by glycophorin C could function as a marker for plaque vulnerability, possibly reflecting intraplaque hemorrhage (IPH), and offering predictive value for pre-procedural neurological symptoms. We employed the CellProfiler-integrated slideToolKit workflow to visualize and quantify glycophorin C, defined as the total plaque area that is positive for glycophorin C, in single slides of culprit lesions obtained from the Athero-Express Biobank of 1819 consecutive asymptomatic and symptomatic patients who underwent carotid endarterectomy. Our assessment included the evaluation of various parameters such as lipid core, calcifications, collagen content, SMC content, and macrophage burden. These parameters were evaluated using a semi-quantitative scoring method, and the resulting data was dichotomized as predefined criteria into categories of no/minor or moderate/heavy staining. In addition, the presence or absence of IPH was also scored. The prevalence of IPH and pre-procedural neurological symptoms were 62.4% and 87.1%, respectively. The amount of glycophorin staining was significantly higher in samples from men compared to samples of women (median 7.15 (IQR:3.37, 13.41) versus median 4.06 (IQR:1.98, 8.32), p < 0.001). Glycophorin C was associated with IPH adjusted for clinical confounders (OR 1.90; 95% CI 1.63, 2.21; p = < 0.001). Glycophorin C was significantly associated with ipsilateral pre-procedural neurological symptoms (OR:1.27, 95%CI:1.06–1.41, p = 0.005). Sex-stratified analysis, showed that this was also the case for men (OR 1.37; 95%CI 1.12, 1.69; p = 0.003), but not for women (OR 1.15; 95%CI 0.77, 1.73; p = 0.27). Glycophorin C was associated with classical features of a vulnerable plaque, such as a larger lipid core, a higher macrophage burden, less calcifications, a lower collagen and SMC content. There were marked sex differences, in men, glycophorin C was associated with calcifications and collagen while these associations were not found in women. To conclude, the accumulation of erythrocytes in atherosclerotic plaque quantified and visualized by glycophorin C was independently associated with the presence of IPH, preprocedural symptoms in men, and with a more vulnerable plaque composition in both men and women. These results strengthen the notion that the accumulation of erythrocytes quantified by glycophorin C can be used as a marker for plaque vulnerability.

Viruses in Laboratory Drosophila and Their Impact on Host Gene Expression.

Drosophila melanogaster has one of the best characterized antiviral immune responses among invertebrates. However, relatively few easily transmitted natural virus isolates are available, and so many Drosophila experiments have been performed using artificial infection routes and artificial host-virus combinations. These may not reflect natural infections, especially for subtle phenotypes such as gene expression. Here, to explore the laboratory virus community and to better understand how natural virus infections induce changes in gene expression, we have analysed seven publicly available D. melanogaster transcriptomic sequencing datasets that were originally sequenced for projects unrelated to virus infection. We have found ten known viruses-including five that have not been experimentally isolated-but no previously unknown viruses. Our analysis of host gene expression revealed that numerous genes were differentially expressed in flies that were naturally infected with a virus. For example, flies infected with nora virus showed patterns of gene expression consistent with intestinal vacuolization and possible host repair via the upd3 JAK/STAT pathway. We also found marked sex differences in virus-induced differential gene expression. Our results show that natural virus infection in laboratory Drosophila does indeed induce detectable changes in gene expression, suggesting that this may form an important background condition for experimental studies in the laboratory.

Growth Hormone Action in Somatostatin Neurons Regulates Anxiety and Fear Memory.

Dysfunctions in growth hormone (GH) secretion increase the prevalence of anxiety and other neuropsychiatric diseases. GH receptor (GHR) signaling in the amygdala has been associated with fear memory, a key feature of posttraumatic stress disorder. However, it is currently unknown which neuronal population is targeted by GH action to influence the development of neuropsychiatric diseases. Here, we showed that approximately 60% of somatostatin (SST)-expressing neurons in the extended amygdala are directly responsive to GH. GHR ablation in SST-expressing cells (SSTΔGHR mice) caused no alterations in energy or glucose metabolism. Notably, SSTΔGHR male mice exhibited increased anxiety-like behavior in the light-dark box and elevated plus maze tests, whereas SSTΔGHR females showed no changes in anxiety. Using auditory Pavlovian fear conditioning, both male and female SSTΔGHR mice exhibited a significant reduction in fear memory. Conversely, GHR ablation in SST neurons did not affect memory in the novel object recognition test. Gene expression was analyzed in a micro punch comprising the central nucleus of the amygdala (CEA) and basolateral (BLA) complex. GHR ablation in SST neurons caused sex-dependent changes in the expression of factors involved in synaptic plasticity and function. In conclusion, GHR expression in SST neurons is necessary to regulate anxiety in males, but not female mice. GHR ablation in SST neurons also decreases fear memory and affects gene expression in the amygdala, although marked sex differences were observed. Our findings identified for the first time a neurochemically-defined neuronal population responsible for mediating the effects of GH on behavioral aspects associated with neuropsychiatric diseases.SIGNIFICANCE STATEMENT Hormone action in the brain regulates different neurological aspects, affecting the predisposition to neuropsychiatric disorders, like depression, anxiety, and posttraumatic stress disorder. Growth hormone (GH) receptor is widely expressed in the brain, but the exact function of neuronal GH action is not fully understood. Here, we showed that mice lacking the GH receptor in a group of neurons that express the neuropeptide somatostatin exhibit increased anxiety. However, this effect is only observed in male mice. In contrast, the absence of the GH receptor in somatostatin-expressing neurons decreases fear memory, a key feature of posttraumatic stress disorder, in males and females. Thus, our study identified a specific group of neurons in which GH acts to affect the predisposition to neuropsychiatric diseases.

Sex- and age-related differences in renal and cardiac injury and senescence in stroke-prone spontaneously hypertensive rats

BackgroundSex differences play a critical role in the incidence and severity of cardiovascular diseases, whereby men are at a higher risk of developing cardiovascular disease compared to age-matched premenopausal women. Marked sex differences at the cellular and tissue level may contribute to susceptibility to cardiovascular disease and end-organ damage. In this study, we have performed an in-depth histological analysis of sex differences in hypertensive cardiac and renal injury in middle-aged stroke-prone spontaneously hypertensive rats (SHRSPs) to determine the interaction between age, sex and cell senescence.MethodsKidneys, hearts and urine samples were collected from 6.5- and 8-month-old (Mo) male and female SHRSPs. Urine samples were assayed for albumin and creatinine content. Kidneys and hearts were screened for a suite of cellular senescence markers (senescence-associated β-galactosidase, p16INK4a, p21, γH2AX). Renal and cardiac fibrosis was quantified using Masson’s trichrome staining, and glomerular hypertrophy and sclerosis were quantified using Periodic acid–Schiff staining.ResultsMarked renal and cardiac fibrosis, concomitant with albuminuria, were evident in all SHRSPs. These sequelae were differentially affected by age, sex and organ. That is, the level of fibrosis was greater in the kidney than the heart, males had greater levels of fibrosis than females in both the heart and kidney, and even a 6-week increase in age resulted in greater levels of kidney fibrosis in males. The differences in kidney fibrosis were reflected by elevated levels of cellular senescence in the kidney in males but not females. Senescent cell burden was significantly less in cardiac tissue compared to renal tissue and was not affected by age or sex.ConclusionsOur study demonstrates a clear sex pattern in age-related progression of renal and cardiac fibrosis and cellular senescence in SHRSP rats. A 6-week time frame was associated with increased indices of cardiac and renal fibrosis and cellular senescence in male SHRSPs. Female SHRSP rats were protected from renal and cardiac damage compared to age-matched males. Thus, the SHRSP is an ideal model to investigate the effects of sex and aging on organ injury over a short timeframe.

Sexual differences in blood parasite infections, circulating carotenoids and body condition in free‐living red‐legged partridges

AbstractA central issue in avian ecology deals with the trade‐off between investment life‐history components, such as reproductive effort, and parasite and disease resistance. During reproduction, differences in the particular needs of males and females may further affect the outcome of such trade‐off. However, most studies performed to date on avian species have focused on males, while less is known about this subject in females. We investigated haemoparasite infections (genera Haemoproteus, Plasmodium and Leucocytozoon) in relation to sex, year, body condition and plasma concentrations of carotenoids in wild‐breeding Red‐legged partridges (Alectoris rufa). Our aim was to examine whether there are differences in infections between sexes and how parasite infections relate to carotenoid levels, physical condition and breeding parameters in non‐passerine wild birds. Males captured early in the breeding season were in better body condition than females, indicating a marked sexual difference in this trait in wild Red‐legged partridges. The prevalence of blood parasites in males was higher than in females. However, we found that females infected by blood parasites had lower plasma carotenoid concentrations than uninfected females, whereas no association between infection and carotenoid levels was found in males. This suggests sex‐related differences in the use of carotenoids to fight infections or for parasite resistance. A possible explanation of this contrasting pattern between sexes is that reproduction may not have to involve the same costs for males and females. We suggest that males would be under strong sexual selection and would trade health for signalling, which could simultaneously explain highest parasite prevalence being found in males and the contrasting patterns in blood carotenoid levels between males and females. Females in contrast, that were in worst body condition during early breeding season, were more sensitive to infections, diverting carotenoids to immune function more than males.

Single-nucleus RNA and ATAC sequencing reveals marked changes and sex differences in the kidney collecting duct principal cell in response to mild dehydration

The kidney principal cells in the connecting tubule (CNTPCs) and collecting duct (CDPCs) function to fine-tune water reabsorption and concentrate the urine upon activation of arginine vasopressin (AVP) receptor-2. Our study aimed to determine the kidney single-nucleus transcriptome and DNA accessibility in response to dehydration, a potent physiological stimulus for AVP secretion. We hypothesized that dehydrated male and female mice would have different responses in the PCs.Male and female C57BL/6J mice at 11 weeks old were subjected to either ad libitum (ad lib) or 9hr of dehydration (n = 1 per group) with samples taken at midnight. 10X Genomics Chromium Next GEM Single Cell Multiome ATAC+Gene Expression Kit was used. The fastq files were processed using CellRanger ARC pipeline and downstream analyses completed with the R packages Seurat and Signac. Gene set enrichment analyses were performed with ToppGene Suite.A total of 22,821 nuclei (median fragments per nucleus = 12,961 ± 336) were sequenced and 34 clusters identified with 586 and 129 nuclei annotated as CDPC and CNTPC, respectively. We found more DEGs in CDPC than in CNTPC (106 vs. 13). The common top 5 most highly expressed genes in both CDPC and CNTPC in the dehydrated state compared to ad lib were Grem2, Pde10a, Pappa, Fam129a, Scg5 (adjusted P values &lt; 0.01). Grem2 encodes a cytokine known to antagonize the bone morphogenic protein family (log2FC adlib/dehydrated for CDPC = -2.18 and CNTPC -1.96). Pde10a is a gene related to cAMP-mediated signaling (log2FC for CDPC = -2.17 and CNTPC -2.02). Pappa encodes a metalloproteinase (log2FC for CDPC = -1.36 and CNTPC -1.24). Fam129a encodes a protein that regulates protein phosphorylation (log2FC for CDPC = -1.17 and CNTPC -1.20). Finally, Scg5 encodes a chaperone protein that regulates pituitary hormone secretion (log2FC for CDPC = -0.84 and CNTPC -0.92). As expected, Aqp2 and Aqp3 were significantly higher in CDPCs from the dehydrated male and female mice. When stratifying by sex, we found more DEGs in female CDPCs than in males (79 vs. 54, χ2 p = 2.68E-8), but in CNTPC there were less in females than in males (1 vs 14, Fisher’s Exact p = 0.016). Pathway analyses determined that in dehydrated male DEGs that were highly expressed were enriched in circulatory system development and response to cAMP signaling pathways. In dehydrated female highly expressed DEGs were enriched in pathways related to renal development. Overall, chromatin analysis showed that changes in gene expression were not driven by changes in accessibility of chromatin.In conclusion, these findings suggest that CDPCs are more responsive to dehydration and that although there are common DEGs in dehydrated male and female mice, unique genes are enriched in different biological processes. NIDDK 1R01DK128001 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Sex-dependent divergence in the effects of GLP-1 agonist exendin-4 on alcohol reinforcement and reinstatement in C57BL/6J mice

RationaleAlcohol use disorder remains a leading cause of preventable deaths, and current treatments have limited efficacy. Glucagon-like peptide 1 (GLP-1) receptor agonists can reduce alcohol drinking in preclinical studies, but mechanisms are still not fully understood, and data in female subjects are scarce.ObjectivesTo assess whether the GLP-1 receptor agonist exendin-4 could decrease alcohol-seeking behavior in the absence of alcohol consumption or intoxication, to compare the potency and efficacy of exendin-4 in the reduction of alcohol seeking vs. alcohol taking, and to compare effects between male and female mice.MethodsMale and female C57BL/6J mice were trained to self-administer 20% alcohol under an FR 1 schedule of reinforcement. After extinction, systemic exendin-4 (saline, 1.8, and 3.2 μg/kg) was tested in cue-induced reinstatement of alcohol seeking. Effects of exendin-4 on alcohol self-administration were tested in a separate group.ResultsExendin-4 suppressed reinstatement of alcohol seeking to extinction levels, at both doses, in the male mice, but had no effect in the female mice. Both doses of exendin-4 also significantly decreased alcohol self-administration in male mice; females again showed less pronounced effects.ConclusionsIn male mice, exendin-4 appeared more effective at suppressing alcohol seeking in the absence of alcohol relative to alcohol self-administration, consistent with modulation of alcohol reward or inhibitory control, rather than satiety or aversive effects of alcohol. We saw marked sex differences with less effect of exendin-4 in female mice, and it will be important to include both sexes in further investigations into GLP-1 receptor agonists.