Sex Differences Research Articles

Sex differences in gray matter, white matter, and regional brain perfusion in young, healthy adults.

Cerebrovascular and neurological diseases exhibit sex-specific patterns in prevalence, severity, and regional specificity, some of which are associated with altered cerebral blood flow (CBF). Females often exhibit higher resting CBF, but understanding the impact of sex per se on CBF is hampered by study variability in age, comorbidities, medications, and control for menstrual cycle or hormone therapies. A majority of studies report whole brain CBF without differentiating between gray and white matter or without assessing regional CBF. Thus fundamental sex differences in regional or whole brain CBF remain unclarified. While controlling for the above confounders, we tested the hypothesis that females will exhibit higher total gray and white matter perfusion as well as regional gray matter perfusion. Adults 18-30 yr old (females = 22 and males = 26) were studied using arterial spin labeling (ASL) magnetic resonance imaging (MRI) scans followed by computational anatomy toolbox (CAT12) analysis in statistical parametric mapping (SPM12) to quantify CBF relative to brain volume. Females displayed 40% higher perfusion globally (females = 62 ± 9 and males = 45 ± 10 mL/100 g/min, P < 0.001), gray matter (females = 75 ± 11 and males = 54 ± 12 mL/100 g/min, P < 0.001), and white matter (females = 44 ± 6 and males = 32 ± 7 mL/100 g/min, P < 0.001). Females exhibited greater perfusion than males in 67 of the 68 regions tested, ranging from 14% to 66% higher. A second MRI approach (4-dimensional flow) focused on large arteries confirmed the sex difference in global CBF. These data indicate strikingly higher basal CBF in females at global, gray, and white matter levels and across dozens of brain regions and offer new clarity into fundamental sex differences in global and regional CBF regulation before aging or pathology.NEW & NOTEWORTHY MRI used to measure cerebral blood flow (CBF) in gray matter, white matter, and 68 regions in healthy men and women. This study demonstrated that CBF is 40% higher in women, the highest sex difference reported, when controlling for numerous important clinical confounders like age, smoking, menstrual cycle, comorbidities, and medications.

The Energetic Saver Profile From Sit-to-Stand Does Not Persist During Very Low-Intensity Physical Activity in Healthy Men and Women.

It is essential to better characterize the energetic profile of individuals during very low-intensity physical activity. The objectives of the present study were to determine whether the saver profile from sit-to-stand persists during light physical activity and characterize patterns in substrate utilization from sit-to-stand and during very low-intensity physical activity in healthy men and women. Sixty-two healthy adults (38 women) performed an experimental sequence that corresponded to 15-minute sitting (SIT1), followed by 15-minute standing (STAND), 15-minute sitting again (SIT2), and finally 15minutes of light cycling. Continuous indirect calorimetry was allowed to calculate energy expenditure (EE) and respiratory quotient through the entire sequence. Savers and nonsavers (<5% and ≥ 5% increase in EE from sitting to standing, respectively) were determined. There was an interaction effect in EE between savers and nonsavers through the whole sequence (P = .008). Only nonsavers (71%) exhibited a significant increase in EE from SIT1 to STAND (P < .001). Nonsavers and savers significantly increased EE during 15minutes of light cycling relative to sitting or standing (P < .001), without any difference between groups. The percentage of change in respiratory quotient from SIT1 to STAND was significantly different between the 2 groups, with increased values in savers and decreased values in nonsavers (P = .03). Significantly lower values in respiratory quotient and EE were found during 15minutes of light cycling in women compared with men (P < .001). It is essential to determine individuals' energetic phenotype to determine those who may benefit more from strategies such as standing or light physical activity. The sexual dimorphism in terms of substrate use during such exercise should be considered.

Sex Differences In Proportional Numbers Of Top Performances Within Elite Youth Track And Field Athletes

Sex Differences In Proportional Numbers Of Top Performances Within Elite Youth Track And Field Athletes

Sex differences in clinical presentation, treatment response, and side effects of nutritional therapy among patients at nutritional risk - a secondary analysis of the randomized clinical trial effort

Sex differences in clinical presentation, treatment response, and side effects of nutritional therapy among patients at nutritional risk - a secondary analysis of the randomized clinical trial effort

Sex Difference In Muscle Sympathetic Nerve Activity During Passive Leg Raising

Sex Difference In Muscle Sympathetic Nerve Activity During Passive Leg Raising

Sex Differences in Fitness, LVEF, and Mortality in Cardiac Rehabilitation Patients

Sex Differences in Fitness, LVEF, and Mortality in Cardiac Rehabilitation Patients

Sex Differences In The Efficacy Of The Short Bouts Of Exercise For Preschoolers (STEP) Intervention

Sex Differences In The Efficacy Of The Short Bouts Of Exercise For Preschoolers (STEP) Intervention

Sex differences in clinical and biological cardiometabolic adaptations following a 12-week citrulline supplementation combined with HIIT in obese older adults

Sex differences in clinical and biological cardiometabolic adaptations following a 12-week citrulline supplementation combined with HIIT in obese older adults

AVIAN HAEMOSPORIDIANS IN GREATER SCAUP (AYTHYA MARILA) AND LESSER SCAUP (AYTHYA AFFINIS) FROM WISCONSIN.

Avian haemosporidians are a diverse group of protozoan parasites that infect a wide range of host species. Waterfowl are an ecologically and economically important group of hosts that have been underrepresented in studies of haemosporidians. Diving ducks have unique life history traits, and morphological, behavioral, and dietary differences separate them from more common dabbling ducks. Greater scaup (Aythya marila) and lesser scaup (Aythya affinis) are closely related diving ducks with declining population trends in North America. To better understand the diversity of haemosporidians within diving ducks and factors related to host infections in scaup, we surveyed 82 hunter-donated waterfowl from 8 species of divers, sea ducks, and dabblers from Green Bay, Wisconsin from 2019 to 2021. We used molecular detection methods and phylogenetic and statistical analyses to describe the diversity, host associations, and prevalence of haemosporidians. We detected 14 unique genetic lineages of haemosporidians, including 4 novel lineages. We identified at least 1 lineage of haemosporidian in each of the 8 host species of divers, sea ducks, and dabblers examined. Lesser scaup had more diverse haemosporidian communities than did greater scaup, but lineages showed no clustering among these hosts when incorporated in phylogenetic analyses with lineages from other Nearctic waterfowl. Female lesser scaup had the highest infection prevalence, but there was no effect of host age or year of sampling. Our findings underscore the importance of species and sex differences that could lead to a higher risk of infections. Our results also fill an important geographical sampling gap for haemosporidians along a key migratory route. Increased monitoring of haemosporidians in waterfowl could contribute to insights into parasite evolution and ecology and the conservation and management of host populations.

Sex differences in clinical and biological muscle adaptations following a 12-week citrulline supplementation combined with HIIT in obese older adults

Sex differences in clinical and biological muscle adaptations following a 12-week citrulline supplementation combined with HIIT in obese older adults

Sex Differences In Biomarkers Of End-organ Damage In Exertional Heat Stroke

Sex Differences In Biomarkers Of End-organ Damage In Exertional Heat Stroke

Epigenetic Clock at Birth and Childhood Blood Pressure Trajectory: A Prospective Birth Cohort Study.

The impact of methylation gestational age (GAmAge; a biomarker of fetal maturity) at birth on childhood blood pressure (BP) trajectories is unknown. This cohort study included 500 boys and 440 girls with data on cord blood DNA methylation and BP at 3 to 15 years of age. Systolic BP (SBP) and diastolic BP percentiles were calculated based on clinical guidelines. Time-series K-means clustering identified 4 distinct SBP and diastolic BP percentile trajectories: high-steady, high-decrease, normal-increase, and normal-steady. GAmAge was estimated using an existing pediatric epigenetic clock. Extrinsic age acceleration was calculated as residuals of associations between GAmAge and chronological gestational age. Intrinsic age acceleration was calculated using the same method adjusting for cord blood cell compositions. Extrinsic age acceleration and intrinsic age acceleration were inversely associated with repeated measures of BP percentiles. Significant inverse associations were observed between extrinsic age acceleration and SBP percentiles in boys (β=-2.02; P=0.02) but not in girls (β=-0.49; P=0.58). Both extrinsic age acceleration and intrinsic age acceleration were inversely associated with SBP percentiles in girls born preterm (<37 weeks; βEAA=-2.95; βIAA=-3.00; P<0.05). Compared with the normal-steady SBP trajectory, significant inverse associations were observed between intrinsic age acceleration and high-steady, high-decrease, and normal-increase SBP trajectories in boys (odds ratio, 0.73-0.81; P<0.03), and significant positive associations were observed for high-decrease and normal-increase SBP trajectories in girls (odds ratio, 1.26-1.38; P<0.01). Significant sex differences were observed (Psex-interaction<2×10-16). GAmAge acceleration at birth was inversely associated with child BP, and such association was more pronounced in boys than in girls. Our findings may shed new light on the developmental origins of high BP and sex differences in cardiovascular risk.

Sex Differences In Contraction-induced Microvascular Oxygen Extraction During Intermittent Maximal-effort Contractions

Sex Differences In Contraction-induced Microvascular Oxygen Extraction During Intermittent Maximal-effort Contractions

Global genomic profile of hippocampal endothelial cells by single-nuclei RNA sequencing in female diabetic mice is associated with cognitive dysfunction.

Type II diabetes mellitus (T2D) is a chronic metabolic disease and a risk factor for cardiovascular disease and cerebrovascular dysfunction including vascular dementia. Sex differences in the prevalence of T2D, dementia, and global genomic changes in the brain have been observed; however, most studies have been performed in males. Therefore, our aim was to evaluate the consequence of T2D on cognitive function and decipher the underlying molecular transcriptomic mechanisms of endothelial cells in an important brain memory center, the hippocampus, using a female murine diabetes model. We assessed cognitive function, metabolic parameters, and then performed hippocampal single-nuclei RNA sequencing (snRNA seq) in adult female db/db and control wild-type (WT) mice. db/db mice exhibited characteristic T2D metabolism with hyperglycemia, hyperinsulinemia, and hyperlipidemia when compared with WT mice. Female db/db mice presented cognitive decline compared with wild-type mice, as determined by open field and Morris water maze tests. snRNAseq showed that T2D induced significant changes in the global transcriptomic profile of hippocampal endothelial cells by modulating the expression of not only protein-coding genes but also long noncoding RNAs. These genes regulate cell-cell junctions, cell chemotaxis, actin cytoskeleton organization, and cell adhesion, suggesting that diabetes increases endothelial cell permeability. Observed genomic changes also correlated with the genetics of persons with clinical Alzheimer's disease and vascular dementia. In conclusion, T2D, by transcriptional and posttranscriptional regulation, regulates endothelial cell dysfunction predictive of increased vascular permeability, and negatively impacts cognitive function. Our work has implications for sex-specific molecular therapeutic targets for dementia in females.NEW & NOTEWORTHY Female db/db mice presented cognitive decline as determined by open field and Morris water maze tests. snRNAseq showed that T2D induced changes in the global transcriptomic profile of hippocampal endothelial cells by modulating the expression of not only protein-coding genes but also long noncoding RNAs. These genes regulate cell-cell junctions, cell chemotaxis, or cell adhesion, suggesting increased endothelial permeability. Genomic changes correlated with the genetics of persons with clinical Alzheimer's disease and vascular dementia.

Sex Differences In Use And Knowledge Of Third-party Tested Nutritional Supplements In Collegiate Athletes

Sex Differences In Use And Knowledge Of Third-party Tested Nutritional Supplements In Collegiate Athletes

Sex Differences In The Facial Expressions Of Effort During Exercise

Sex Differences In The Facial Expressions Of Effort During Exercise

Hypertension disrupts the vascular clock in both sexes.

Blood pressure (BP) displays a circadian rhythm and disruptions in this pattern elevate cardiovascular risk. Although both central and peripheral clock genes are implicated in these processes, the importance of vascular clock genes is not fully understood. BP, vascular reactivity, and the renin-angiotensin-aldosterone system display overt sex differences, but whether changes in circadian patterns underlie these differences is unknown. Therefore, we hypothesized that circadian rhythms and vascular clock genes would differ across sex and would be blunted by angiotensin II (ANG II)-induced hypertension. ANG II infusion elevated BP and disrupted circadian patterns similarly in both males and females. In females, an impact on heart rate (HR) and locomotor activity was revealed, whereas in males hypertension suppressed baroreflex sensitivity (BRS). A marked disruption in the vascular expression patterns of period circadian regulator 1 (Per1) and brain and muscle aryl hydrocarbon receptor nuclear translocator like protein 1 (Bmal1) was noted in both sexes. Vascular expression of the G protein-coupled estrogen receptor (Gper1) also showed diurnal synchronization in both sexes that was similar to that of Per1 and Per2 and disrupted by hypertension. In contrast, vascular expression of estrogen receptor 1 (Esr1) showed a diurnal rhythm and hypertension-induced disruption only in females. This study shows a strikingly similar impact of hypertension on BP rhythmicity, vascular clock genes, and vascular estrogen receptor expression in both sexes. We identified a greater impact of hypertension on locomotor activity and heart rate in females and on baroreflex sensitivity in males and also revealed a diurnal regulation of vascular estrogen receptors. These insights highlight the intricate ties between circadian biology, sex differences, and cardiovascular regulation.NEW & NOTEWORTHY This study reveals that ANG II-induced hypertension disrupts the circadian rhythm of blood pressure in both male and female mice, with parallel effects on vascular clock gene and estrogen receptor diurnal patterns. Notably, sex-specific responses to hypertension in terms of locomotor activity, heart rate, and baroreflex sensitivity are revealed. These findings pave the way for chronotherapeutic strategies tailored to mitigate cardiovascular risks associated with disrupted circadian rhythms in hypertension.

Characterization of Human Shoulder Joint Stiffness Across 3D Arm Postures and Its Sex Differences.

Understanding the characteristics of shoulder joint stiffness can offer insights into how the shoulder joint contributes to arm stability and assists in various arm postures and movements. This study aims to characterize posture-dependent shoulder stiffness in a three-dimensional (3D) space and investigate its potential sex differences. A multi-degree-of-freedom, parallel-actuated shoulder exoskeleton robot was used' to perturb the participant's shoulder joint and measure the resulting torque responses while participants relaxed their shoulder muscles. The group average results of 40 healthy individuals (20 males and 20 females) revealed that arm postures significantly affect shoulder stiffness, particularly in postures involving shoulder flexion/extension and horizontal flexion/extension. Shoulder stiffness consistently increased as the shoulder flexion angle decreased and the shoulder horizontal flexion/extension approached the limit of its range of motion. The comparative group results between males and females indicated that shoulder stiffness in males was greater than that in females across all 15 arm postures measured in this study. Even after normalizing the data by subject body mass, the female group showed significantly lower stiffness than the male group in 12 out of the 15 arm postures. The results highlight that 3D arm postures and sex significantly affect shoulder stiffness even under relaxed muscles. This study provides valuable foundations for future studies aimed at characterizing shoulder stiffness in the context of active muscles and dynamic movement tasks, evaluating changes in shoulder stiffness following neuromuscular injuries, and formulating rehabilitative training protocols for individuals suffering from shoulder problems.

Sex differences in the association between social frailty and diet quality among older adults in Spain

ObjectiveThe aim was to examine the association between social frailty and diet quality in adults over 65 years of age, and whether results differed by sex. DesignPopulation-based cross-sectional study using data from the Spanish National Health Survey. Participants5,071 community-dwelling people ≥65 years from Spain. MeasurementsSocial frailty was deemed to exist when the person both lived alone and had low social support, measured with the Duke-UNC scale. Diet was assessed with the Spanish Healthy Eating Index (S-HEI), ranging from 0 to 100 points (highest diet quality). Means and 95% confidence intervals of the S-HEI score for each social frailty group were calculated using linear regressions, with socially robust people as reference. Analyses were adjusted for main confounders, including sociodemographic, lifestyle and morbidity variables. ResultsThere were no differences in the S-HEI adjusted mean of socially frail (74.3 points, 95%CI: 73.4−75.2) compared to socially robust older adults (75.4 points; 95%CI: 75.1−75.7). In sex-stratified analyses, the S-HEI adjusted mean of socially frail men (71.9 points; 95%CI: 70.6−73.2) was lower than robust men (74.8 points; 95%CI: 74.4−75.3). Specifically, social frailty was associated with lower consumption of vegetables, fruits, dairy and lower diet variety in men. Differences were not observed according to social frailty among older women. ConclusionsSocial frailty was associated with poor diet quality in community-dwelling older men, but not in women in Spain. Gender differences in self-care could partly explain this association. Sex-specific interventions are required to minimize the impact of social frailty on diet quality.

Sex differences in symptoms and response to Mediterranean Diet in diverticular disease

Sex differences in symptoms and response to Mediterranean Diet in diverticular disease