Single cell regulatory architecture of human pancreatic islets suggests sex differences in β cell function and the pathogenesis of type 2 diabetes

Biological sex affects the pathogenesis of type 2 and type 1 diabetes (T2D, T1D) including the development of β cell failure observed more often in males. The mechanisms that drive sex differences in β cell failure is unknown. Studying sex differences in islet regulation and function represent a unique avenue to understand the sex-specific heterogeneity in β cell failure in diabetes. Here, we examined sex and race differences in human pancreatic islets from up to 52 donors with and without T2D (including 37 donors from the Human Pancreas Analysis Program [HPAP] dataset) using an orthogonal series of experiments including single cell RNA-seq (scRNA-seq), single nucleus assay for transposase-accessible chromatin sequencing (snATAC-seq), dynamic hormone secretion, and bioenergetics. In cultured islets from nondiabetic (ND) donors, in the absence of the in vivo hormonal environment, sex differences in islet cell type gene accessibility and expression predominantly involved sex chromosomes. Of particular interest were sex differences in the X-linked KDM6A and Y-linked KDM5D chromatin remodelers in female and male islet cells respectively. Islets from T2D donors exhibited similar sex differences in differentially expressed genes (DEGs) from sex chromosomes. However, in contrast to islets from ND donors, islets from T2D donors exhibited major sex differences in DEGs from autosomes. Comparing β cells from T2D and ND donors revealed that females had more DEGs from autosomes compared to male β cells. Gene set enrichment analysis of female β cell DEGs showed a suppression of oxidative phosphorylation and electron transport chain pathways, while male β cell had suppressed insulin secretion pathways. Thus, although sex-specific differences in gene accessibility and expression of cultured ND human islets predominantly affect sex chromosome genes, major differences in autosomal gene expression between sexes appear during the transition to T2D and which highlight mitochondrial failure in female β cells.

Maternal Western diet programs cardiometabolic dysfunction and hypothalamic inflammation via epigenetic mechanisms predominantly in the male offspring

OBJECTIVE

Maternal exposure during pregnancy is a strong determinant of offspring health outcomes. Such exposure induces changes in the offspring epigenome resulting in gene expression and functional changes. In this study, we investigated the effect of maternal Western hypercaloric diet (HCD) programming during the perinatal period on neuronal plasticity and cardiometabolic health in adult offspring.

METHODS

C57BL/6J dams were fed HCD for 1 month prior to mating with regular diet (RD) sires and kept on the same diet throughout pregnancy and lactation. At weaning, offspring were maintained on either HCD or RD for 3 months resulting in 4 treatment groups that underwent cardiometabolic assessments. DNA and RNA were extracted from the hypothalamus to perform whole genome methylation, mRNA, and miRNA sequencing followed by bioinformatic analyses.

RESULTS

Maternal programming resulted in male-specific hypertension and hyperglycemia, with both males and females showing increased sympathetic tone to the vasculature. Surprisingly, programmed male offspring fed HCD in adulthood exhibited lower glucose levels, less insulin resistance, and leptin levels compared to non-programmed HCD-fed male mice. Hypothalamic genes involved in inflammation and type 2 diabetes were targeted by differentially expressed miRNA, while genes involved in glial and astrocytic differentiation were differentially methylated in programmed male offspring. These data were supported by our findings of astrogliosis, microgliosis and increased microglial activation in programmed males in the paraventricular nucleus (PVN). Programming induced a protective effect in male mice fed HCD in adulthood, resulting in lower protein levels of hypothalamic TGFβ2, NF-κB2, NF-κBp65, Ser-pIRS1, and GLP1R compared to non-programmed HCD-fed males. Although TGFβ2 was upregulated in male mice exposed to HCD pre- or post-natally, only blockade of the brain TGFβ receptor in RD-HCD mice improved glucose tolerance and a trend to weight loss.

CONCLUSIONS

Our study shows that maternal HCD programs neuronal plasticity in the offspring and results in male-specific hypertension and hyperglycemia associated with hypothalamic inflammation in mechanisms and pathways distinct from post-natal HCD exposure. Together, our data unmask a compensatory role of HCD programming, likely via priming of metabolic pathways to handle excess nutrients in a more efficient way.

Sex differences in energy metabolism: natural selection, mechanisms and consequences

Metabolic homeostasis operates differently in men and women. This sex asymmetry is the result of evolutionary adaptations that enable women to resist loss of energy stores and protein mass while remaining fertile in times of energy deficit. During starvation or prolonged exercise, women rely on oxidation of lipids, which are a more efficient energy source than carbohydrates, to preserve glucose for neuronal and placental function and spare proteins necessary for organ function. Carbohydrate reliance in men could be an evolutionary adaptation related to defence and hunting, as glucose, unlike lipids, can be used as a fuel for anaerobic high-exertion muscle activity. The larger subcutaneous adipose tissue depots in healthy women than in healthy men provide a mechanism for lipid storage. As female mitochondria have higher functional capacity and greater resistance to oxidative damage than male mitochondria, uniparental inheritance of female mitochondria may reduce the transmission of metabolic disorders. However, in women, starvation resistance and propensity to obesity have evolved in tandem, and the current prevalence of obesity is greater in women than in men. The combination of genetic sex, programming by developmental testosterone in males, and pubertal sex hormones defines sex-specific biological systems in adults that produce phenotypic sex differences in energy homeostasis, metabolic disease and drug responses.

Sex Differences in Cardiovascular Risk Associated With Prediabetes and Undiagnosed Diabetes

INTRODUCTION

Women with Type 2 diabetes (T2D) face up to 50% higher risk of cardiovascular disease than men. This study evaluated the extent to which prediabetes and undiagnosed T2D are associated with a greater excess risk of cardiovascular disease in women versus in men.

METHODS

Data were pooled from 18,745 cardiovascular disease-free individuals from the Atherosclerosis Risk in Communities Study, the Multi-Ethnic Study of Atherosclerosis, and the Jackson Heart Study. The risk of coronary heart disease, ischemic stroke, and atherosclerotic cardiovascular disease (coronary heart disease or stroke) associated with prediabetes or undiagnosed T2D was estimated using Cox models adjusting for sociodemographic factors, concomitant risk factors, medication use, and menopausal status. Data were collected in 2022, and the analysis was performed in 2023.

RESULTS

During a median follow-up of 18.6 years, the associations between prediabetes and risk of atherosclerotic cardiovascular disease were only significant in women (hazard ratio=1.18, 95% CI=1.01, 1.34, p=0.03) but not in men (hazard ratio=1.08, 95% CI=1.00, 1.28, p=0.06) (p-interaction=0.18). The associations between undiagnosed T2D and cardiovascular disease outcomes were significant in both sexes, but the effect was more pronounced in women (coronary heart disease: hazard ratio=1.83, 95% CI=1.4, 2.41, p<0.0001 in women vs hazard ratio=1.6, 95% CI=1.38, 2.07, p=0.007 in men; stroke: hazard ratio=1.99, 95% CI=1.39, 2.72, p<0.0001 vs hazard ratio=1.81, 95% CI=1.36, 2.6, p<0.0001; atherosclerotic cardiovascular disease: hazard ratio=1.86, 95% CI=1.5, 2.28, p<0.0001 vs hazard ratio=1.65, 95% CI=1.4, 1.98, p<0.0001) (all p-interactions≤0.2). Both White and Black patients exhibit similar sex differences.

CONCLUSIONS

Prediabetes or undiagnosed T2D was associated with a greater excess risk of cardiovascular disease in women than in men. The sex differential in cardiovascular disease risk among those without the T2D diagnosis suggests the need for sex-specific guidelines in T2D screening and treatment.

Testosterone Deficiency Promotes Arterial Stiffening Independent of Sex Chromosome Complement

Background

Testosterone plays a vital role in men's health. Lower testosterone level is associated with cardiovascular and cardiometabolic diseases, including inflammation, atherosclerosis, and type 2 diabetes. Testosterone replacement is beneficial or neutral to men's cardiovascular health. Testosterone deficiency is associated with cardiovascular events. Testosterone supplementation to hypogonadal men improves libido, increases muscle strength, and enhances mood. We hypothesized that sex chromosomes (XX and XY) interaction with testosterone plays a role in arterial stiffening.

Methods

We used four core genotype male mice to understand the inherent contribution of sex hormones and sex chromosome complement in arterial stiffening. Age-matched mice were either gonadal intact or castrated for eight weeks, followed by an assessment of blood pressure, pulse wave velocity, echocardiography, and ex vivo passive vascular mechanics.

Results

Arterial stiffening but not blood pressure was more significant in castrated than testes-intact mice independent of sex chromosome complement. Castrated mice showed a leftward shift in stress-strain curves and carotid wall thinning. Sex chromosome complement (XX) in the absence of testosterone increased collagen deposition in the aorta and Kdm6a gene expression.

Conclusion

Testosterone deprivation increases arterial stiffening and vascular wall remodeling. Castration increases Col1α1 in male mice with XX sex chromosome complement. Our study shows decreased aortic contractile genes in castrated mice with XX than XY sex chromosomes.

Sex hormones, sex chromosomes, and microbiota: Identification of Akkermansia muciniphila as an estrogen-responsive microbiota

Microbiota composition is known to be linked to sex. However, separating sex hormones and sex chromosome roles in gut microbial diversity is yet to be determined. To investigate the sex chromosome role independent of sex hormones, we used the four-core genotype mouse model. In this mouse model, males with testes and females with ovaries have XX or XY sex chromosome complement. In gonadectomized four-core genotype mice, we observed a significant decrease in the levels of estradiol (P<0.001) and progesterone (P<0.03) in female and testosterone (P<0.0001) in male mice plasma samples. Independent of sex chromosome complement, microbial α diversity was increased in gonadectomized female but not male mice compared to sex-matched gonad-intact controls. β diversity analysis showed separation between male (P<0.05) but not female XX and XY mice. Importantly, Akkermansia muciniphila was less abundant in gonadectomized compared to gonadal intact female mice (P<0.0001). In the presence of β-estradiol, Akkermansia muciniphila growth exponentially increased, providing evidence for the identification of a female sex hormone-responsive bacterium (P<0.001).

Sex differences in cardiometabolic biomarkers during the pre-diabetes stage

Using two large prospective epidemiological studies in the U.S., we examined biomarkers that reflect sex-specific pathophysiological pathways to cardiovascular complications among people with pre-diabetes. Women with pre-diabetes exhibited higher levels of adipokines, while men had lower eGFR. Sex differences in lipoproteins and vascular inflammatory markers during pre-diabetes indicate sex-specific lipoprotein and inflammatory mechanisms to cardiovascular complications.

Sex-specific actions of estradiol and testosterone on human fibroblast and endothelial cell proliferation, bioenergetics, and vasculogenesis

Progress toward the development of sex-specific tissue engineered systems has been hampered by the lack of research efforts to define the effects of sex-specific hormone concentrations on relevant human cell types. Here, we investigated the effects of defined concentrations of estradiol (E2) and dihydrotestosterone (DHT) on primary human dermal and lung fibroblasts (HDF and HLF), and human umbilical vein endothelial cells (HUVEC) from female (XX) and male (XY) donors in both 2D expansion cultures and 3D stromal vascular tissues. Sex-matched E2 and DHT stimulation in 2D expansion cultures significantly increased the proliferation index, mitochondrial membrane potential, and the expression of genes associated with bioenergetics (Na+/K+ ATPase, somatic cytochrome C) and beneficial stress responses (chaperonin) in all cell types tested. Notably, cross sex hormone stimulation, i.e., DHT treatment of XX cells in the absence of E2 and E2 stimulation of XY cells in the absence of DHT, decreased bioenergetic capacity and inhibited cell proliferation. We used a microengineered 3D vasculogenesis assay to assess hormone effects on tissue scale morphogenesis. E2 increased metrics of vascular network complexity compared to vehicle in XX tissues. Conversely, and in line with results from 2D expansion cultures, E2 potently inhibited vasculogenesis compared to vehicle in XY tissues. DHT did not significantly alter vasculogenesis in XX or XY tissues but increased the number of non-participating endothelial cells in both sexes. This study establishes a scientific rationale and adaptable methods for using sex hormone stimulation to develop sex-specific culture systems.

Estetrol Is Safe and Well Tolerated during Treatment of Hospitalized Men and Women with Moderate COVID-19 in a Randomized, Double-Blind Study

Epidemiological data suggest that the severe acute respiratory syndrome coronavirus 2 infection rate is higher in women than in men, but the death rate is lower, while women (>50 years) on menopausal hormone therapy (MHT) have a higher survival rate than those not on MHT. Classical oral estrogen enhances the synthesis of coagulation markers and may increase the risk of thromboembolic events that are common in coronavirus disease 2019 (COVID-19). The favorable hemostatic profile of estetrol (E4) might be suitable for use in women who are receiving estrogen treatment and contract COVID-19. A multicenter, randomized, double-blind, placebo-controlled, phase 2 study (NCT04801836) investigated the efficacy, safety, and tolerability of E4 versus placebo in hospitalized patients with moderate COVID-19. Eligible postmenopausal women and men (aged ≥ 18 years old) were randomized to E4 15 mg or placebo, once daily for 21 days, in addition to the standard of care (SoC). The primary efficacy endpoint of improvement in COVID-19 (percentage of patients recovered at day 28) between the placebo and E4 arms was not met. E4 was well tolerated, with no safety signals or thromboembolic events, suggesting that postmenopausal women can safely continue E4-based therapy in cases of moderate COVID-19 managed with SoC.

Architecture of androgen receptor pathways amplifying glucagon-like peptide-1 insulinotropic action in male pancreatic β cells

Male mice lacking the androgen receptor (AR) in pancreatic β cells exhibit blunted glucose-stimulated insulin secretion (GSIS), leading to hyperglycemia. Testosterone activates an extranuclear AR in β cells to amplify glucagon-like peptide-1 (GLP-1) insulinotropic action. Here, we examined the architecture of AR targets that regulate GLP-1 insulinotropic action in male β cells. Testosterone cooperates with GLP-1 to enhance cAMP production at the plasma membrane and endosomes via: (1) increased mitochondrial production of CO2, activating the HCO3--sensitive soluble adenylate cyclase; and (2) increased Gαs recruitment to GLP-1 receptor and AR complexes, activating transmembrane adenylate cyclase. Additionally, testosterone enhances GSIS in human islets via a focal adhesion kinase/SRC/phosphatidylinositol 3-kinase/mammalian target of rapamycin complex 2 actin remodeling cascade. We describe the testosterone-stimulated AR interactome, transcriptome, proteome, and metabolome that contribute to these effects. This study identifies AR genomic and non-genomic actions that enhance GLP-1-stimulated insulin exocytosis in male β cells.

Effect of menopausal hormone therapy on COVID-19 severe outcomes in women - A population-based study of the US National COVID Cohort Collaborative (N3C) data

Whether menopausal hormone therapy (MHT) lessens the severity of COVID-19 among women is unclear. Leveraging a U.S. national COVID-19 cohort and a cross-sectional analysis, we found MHT use was marginally associated with a lower risk of mortality (odds ratio [OR] 0.73, 95 % CI 0.53-1.01) and significantly associated with a lower risk of prolonged hospital stay (0.7, 0.49-0.99) among inpatient women. When stratifying by MHT type, estrogen-only and estrogen-plus-progestin therapies had a more prominent protective effect than progestin-only therapy, although this difference did not achieve statistical significance. Women with COVID-19 can continue to use MHT. Clinical trials are needed to evaluate MHT's therapeutic effect on COVID-19, especially in terms of severity.

Association Between Metabolic Syndrome Inflammatory Biomarkers and COVID-19 Severity

Context

Metabolic syndrome (MetS) is associated with increased risk of severe COVID-19. MetS inflammatory biomarkers share similarities with those of COVID-19, yet this association is poorly explored.

Objective

Biomarkers of COVID-19 patients with and without MetS, the combination of diabetes, hypertension, obesity, and/or dyslipidemia, were analyzed to identify biological predictors of COVID-19 severity.

Methods

In this prospective observational study, at a large academic emergency department in Boston, Massachusetts, clinical and proteomics data were analyzed from March 24 to April 30, 2020. Patients age ≥18 with a clinical concern for COVID-19 upon arrival and acute respiratory distress were included. The main outcome was severe COVID-19 as defined using World Health Organization COVID-19 outcomes scores ≤4, which describes patients who died, required invasive mechanical ventilation, or required supplemental oxygen.

Results

Among 155 COVID-19 patients, 90 (58.1%) met the definition of MetS and 65 (41.9%) were identified as Control. The MetS cohort was more likely to have severe COVID-19 compared with the Control cohort (OR 2.67 [CI 1.09-6.55]). Biomarkers, including CXCL10 (OR 1.94 [CI 1.38-2.73]), CXCL9 (OR 1.79 [CI 1.09-2.93]), HGF (OR 3.30 [CI 1.65-6.58]), and IL6 (OR 2.09 [CI 1.49-2.94]) were associated with severe COVID-19. However, when stratified by MetS, only CXCL10 (OR 2.39 [CI 1.38-4.14]) and IL6 (OR 3.14 [CI 1.53-6.45]) were significantly associated with severe COVID-19.

Conclusions

MetS-associated severe COVID-19 is characterized by an immune signature of elevated levels of CXCL10 and IL6. Clinical trials targeting CXCL10 or IL6 antagonism in this population may be warranted.

Rising Prediabetes, Undiagnosed Diabetes, and Risk Factors in Young Women

INTRODUCTION

Women of reproductive age are less prone to cardiovascular disease than men. However, diabetes mellitus negates this female advantage. The prevalence change of prediabetes (prediabetes mellitus) and diabetes mellitus and diabetes mellitus‒associated cardiovascular risk factors have not been clearly described in women before menopause.

METHODS

Using National Health and Nutrition Examination Survey data (1999-2018), this study estimated the age-adjusted prevalence of prediabetes mellitus (2005-2018), diagnosed diabetes mellitus, and undiagnosed diabetes mellitus in premenopausal women. Logistic regression was used to examine cardiovascular risk factors, including obesity, central obesity, hypercholesterolemia, hypertension, and hypertriglyceridemia, associated with prediabetes mellitus, diagnosed diabetes mellitus, or undiagnosed diabetes mellitus in premenopausal women. The magnitude of the association among age-matched men and postmenopausal women was compared. The analysis was conducted in 2022.

RESULTS

Premenopausal women experienced an increased prevalence of prediabetes mellitus and undiagnosed diabetes mellitus, contrasting with steady trends in all U.S. adults over the last 2 decades. Premenopausal women with prediabetes mellitus or diabetes mellitus (versus those with normoglycemia) have significant obesity risk, and the risk is equivalent to that among age-matched men and higher than that among postmenopausal women. The association between prediabetes mellitus and hypercholesterolemia or hypertriglyceridemia was significant in premenopausal women only. Hypercholesterolemia and hypertension associated with undiagnosed diabetes mellitus were significant in premenopausal women and men of the same age, respectively. Diagnosed and undiagnosed diabetes mellitus was associated with hypertriglyceridemia in men and postmenopausal women, respectively.

CONCLUSIONS

Premenopausal women had increased prediabetes mellitus and undiagnosed diabetes mellitus in the past 2 decades. They face a considerable cardiovascular risk burden associated with prediabetes mellitus and diabetes mellitus. Cardiometabolic risk screening and patient education should be improved in young and early middle-aged adults, particularly in women.

Abstract P162: Sex Differences in Cardiometabolic Biomarkers During Pre-Diabetes

Background: Diabetes (DM) diminishes female protection against cardiovascular disease (CVD). Women with DM face excess CVD risk than men partly due to women’s greater deterioration in risk factors before DM. In this study, we compared sex differences in biomarkers that reflect distinct pathophysiological pathways during the pre-diabetes (pre-DM) stage.

Method: A cross-sectional analysis was performed based on pooled data from Atherosclerosis Risk in Communities Study and the Jackson Heart Study. We used multivariable linear regressions to examine the associations between sex and biomarkers (log-transformed) representative of inflammation, lipoprotein, adipokine, kidney function, cardiac injury/stress, and thrombosis, adjusted for age, race, and BMI, among CVD-free individuals with pre-DM. We validated the results in a sensitivity analysis, including those that eventually progressed into DM during the follow-up. We used the false discovery rate method to adjust multiple comparisons.

Results: Among 5975 individuals with pre-DM, the mean age was 54.2 years, 2853 (48%) were women, and 2022 (34%) were non-Hispanic blacks. In the adjusted models, inflammatory biomarkers, including high-sensitivity c-reactive proteins (β coefficient 0.2, P=2.9 x 10 -9 ), fibrinogen (β 0.19, P=2.8E-12), and absolute lymphocyte (β 0.25, P=2.54 x 10 -7 ), and cardiac injury/stress biomarker, NT-proBNT (β 0.14, P=0.0002) were higher in women than men with pre-DM. Additionally, lipoprotein(a) (β 0.19, P=4.96 x 10 -13 ) and apolipoproteins A1 (β 0.61, P=2.81x 10 -120 ), and adipokines including leptin (β 1.1, P=2.62 x 10 -123 ) and adiponectin (β 0.56, P=1.94 x 10 -12 ) were all higher in women with pre-DM. In contrast, kidney function markers, albumin (β -0.24, P=2.79 x 10 -9 ) and creatinine (β -1.1, P=1x 10 -100 ), and thrombosis biomarker, homocysteine (β -0.5, P=9.09 x 10 -19 ) were higher in men with pre-DM than in their women counterparts. These sex differences remained generally unchanged among 2320 individuals that progressed into DM.

Conclusion: Biomarkers differ significantly between sexes during the pre-DM state. The inflammatory, lipoprotein, adipokine, and cardiac stress biomarkers were higher in women with pre-DM, while kidney function and thrombosis biomarkers were higher in men with pre-DM. Future mechanistic studies are warranted to delineate pathophysiological pathways characterized by these biomarkers contributing to sex disparities of CVD risk in DM.

Abstract MP60: Prediabetes and Undiagnosed Diabetes Predisposing Women to Excess Risk of Cardiovascular Disease

Objective: Women with type 2 diabetes (T2DM) have a 25-50% higher risk of cardiovascular disease (CVD) than their men counterparts. The reasons for this sex disparity are incompletely understood. We sought to examine if pre-diabetes (preDM) and undiagnosed T2DM are associated with a greater magnitude of CVD risk in women than in men.

Methods: We pooled CVD-free individuals (N=18,745) from the Atherosclerosis Risk in Communities, the Multi-Ethnic Study of Atherosclerosis, and the Jackson Heart Study. CVD outcomes included incident coronary heart disease (CHD) (myocardial infarction, CHD death, or cardiac procedures including percutaneous coronary interventions, bypass surgery, or coronary revascularization), stroke (ischemic or hemorrhagic stroke), and a composite atherosclerotic CVD (ASCVD) (any CHD condition or stroke). Multivariable Cox models examined the outcomes associated with preDM (fasting glucose [FG] 100-125 mg/dL or HbA1c 5.7-6.4%) or undiagnosed T2DM (FG ≥126 mg/dL or HbA1c ≥6.5% and without a DM diagnosis or anti-diabetes medication use) adjusted for age, race/ethnicity, education, BMI, blood pressure, total cholesterols, smoking, anti-hypertensive and lipid-lowering medications, and cohort indicator. An interaction term sex x preDM or undiagnosed DM was added to models to test the sex modifying effect. We consider p-interaction<0.2 as significant.

Results: During a median follow-up of 17 years, the adjusted model showed that preDM was significantly associated with a higher risk of CHD (Hazard ratio 1.09, 95%CI 1.04-1.14), stroke (1.08, 1.04-1.13), and ASCVD (1.09, 1.04-1.14) in women, but not in men (1.04, 0.99-1.1 for CHD, 1.03, 0.98-1.08 for stroke, and 1.03, 0.98-1.09 for ASCVD, respectively). Undiagnosed T2DM was significantly associated with the risk of CHD (1.27, 1.16-1.4 in women and 1.17, 1.05-1.3 in men), stroke (1.32, 1.21-1.45 in women and 1.2, 1.09-1.32 in men), and ASCVD (1.27, 1.16-1.4 in women and 1.15, 1.03-1.29 in men) in both sexes but with more pronounced effect in women (P-interactions ≤0.11). In racial-stratified analysis, a higher magnitude of CVD risk associated with preDM or undiagnosed DM was also found in non-Hispanic (NH) white women and NH-black women than in their men counterparts.

Conclusions: PreDM and undiagnosed DM predispose women to excess CVD risk, possibly due to women’s higher susceptibility to metabolic dysfunction at a lower glucose level and the prolonged unmanaged time for risk factors relative to men. T2DM screening and risk factor control should be enhanced in both sexes to reduce future CVD risk, particularly in women.

Gender differences in health protective behaviours and its implications for COVID-19 pandemic in Taiwan: a population-based study

Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection produces more severe symptoms and a higher mortality in men than in women. The role of biological sex in the immune response to SARS-CoV-2 is believed to explain this sex disparity. However, the contribution of gender factors that influence health protective behaviors and therefore health outcomes, remains poorly explored.

Methods

We assessed the contributions of gender in attitudes towards the COVID-19 pandemic, using a hypothetical influenza pandemic data from the 2019 Taiwan Social Change Survey. Participants were selected through a stratified, three-stage probability proportional-to-size sampling from across the nation, to fill in questionnaires that asked about their perception of the hypothetical pandemic, and intention to adopt health protective behaviors.

Results

A total of 1,990 participants (median age = 45·92 years, 49% were women) were included. Significant gender disparities (p < .001) were observed. The risk perception of pandemic (OR = 1·28, 95% CI [1·21 − 1·35], p < .001), older age (OR = 1·06, 95% CI [1·05 − 1·07], p < .001), female gender (OR = 1·18, 95% CI [1·09-1·27], p < .001), higher education (OR = 1·10, 95% CI [1·06 − 1·13], p < .001), and larger family size (OR = 1·09, 95% CI [1·06 − 1·15], p < .001) were positively associated with health protective behaviors. The risk perception of pandemic (OR = 1·25, 95% CI [1·15 − 1·36]), higher education (OR = 1·07, 95% CI [1·02 − 1·13], p < .05), being married (OR = 1·17, 95% CI [1·01–1·36, p < .05), and larger family size (OR = 1·33, 95% CI [1·25 − 1·42], p < .001), were positively associated with intention to receive a vaccine. However, female gender was negatively associated with intention to receive a vaccine (OR = 0·85, 95% CI [0·75 − 0·90], p < ·01) and to comply with contact-tracing (OR = 0·95, 95% CI [0·90 − 1·00], p < .05) compared to men. Living with children was also negatively associated with intention to receive vaccines (OR = 0·77, 95% CI [0·66 − 0·90], p < .001).

Conclusion

This study unveils gender differences in risk perception, health protective behaviors, vaccine hesitancy, and compliance with contact-tracing using a hypothetical viral pandemic. Gender-specific health education raising awareness of health protective behaviors may be beneficial to prevent future pandemics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14288-1.

Sex differences in determinants of COVID-19 severe outcomes - findings from the National COVID Cohort Collaborative (N3C)

OBJECTIVE

The impact of comorbidities and biomarkers on COVID-19 severity vary by sex but have not yet been verified in population-based studies. We examined the association of comorbidities, inflammatory biomarkers, and severe outcomes in men and women hospitalized for COVID-19.

DESIGN

This is a retrospective cohort analysis based on the National COVID Cohort Collaborative (N3C). We included 574,391 adult patients admitted for COVID-19 at hospitals or emergency rooms between 01/01/2020 and 12/31/2021.

METHODS

We defined comorbidities at or before the first admission for COVID-19 by Charlson Comorbidity Index (CCI) and CCI components. We used the averaged lab values taken within 15 days before or after the admission date to measure biomarkers including c-reactive protein (CRP), ferritin, procalcitonin, N-terminal pro b-type natriuretic peptide (NT proBNP), d-dimer, absolute lymphocyte counts, absolute neutrophil counts, and platelets. Our primary outcome was all-cause mortality; secondary outcomes were invasive mechanical ventilation (IMV) and hospital length of stay (LOS). We used logistic regression adjusted for age, race, ethnicity, visit type, and medications to assess the association of comorbidities, biomarkers, and mortality disaggregating by sex.

RESULTS

Moderate to severe liver disease, renal disease, metastatic solid tumor, and myocardial infarction were the top four fatal comorbidities among patients who were hospitalized for COVID-19 (adjusted odds ratio [aOR] > 2). These four comorbid conditions remained the most lethal in both sexes, with a higher magnitude of risk in women than in men (p-interaction < 0.05). Abnormal elevations of CRP, ferritin, procalcitonin, NT proBNP, neutrophil, and platelet counts, and lymphocytopenia were significantly associated with the risk of death, with procalcitonin and NT proBNP as the strongest predictors (aOR > 2). The association between the abnormal biomarkers and death was stronger in women than in men (p-interaction < 0.05).

CONCLUSION

There are sex differences in inpatient mortality associated with comorbidities and biomarkers. The significant impact of these clinical determinants in women with COVID-19 may be underappreciated as previous studies stressed the increased death rate in male patients that is related to comorbidities or inflammation. Our study highlights the importance and the need for sex-disaggregated research to understand the risk factors of poor outcomes and health disparities in COVID-19.

Membrane-Initiated Estrogen, Androgen, and Progesterone Receptor Signaling in Health and Disease

Rapid effects of steroid hormones were discovered in the early 1950s, but the subject was dominated in the 1970s by discoveries of estradiol and progesterone stimulating protein synthesis. This led to the paradigm that steroid hormones regulate growth, differentiation, and metabolism via binding a receptor in the nucleus. It took 30 years to appreciate not only that some cellular functions arise solely from membrane-localized steroid receptor (SR) actions, but that rapid sex steroid signaling from membrane-localized SRs is a prerequisite for the phosphorylation, nuclear import, and potentiation of the transcriptional activity of nuclear SR counterparts. Here, we provide a review and update on the current state of knowledge of membrane-initiated estrogen (ER), androgen (AR) and progesterone (PR) receptor signaling, the mechanisms of membrane-associated SR potentiation of their nuclear SR homologues, and the importance of this membrane-nuclear SR collaboration in physiology and disease. We also highlight potential clinical implications of pathway-selective modulation of membrane-associated SR.

Emerging diabetes therapies: Bringing back the β-cells

BACKGROUND

Stem cell therapies are finally coming of age as a viable alternative to pancreatic islet transplantation for the treatment of insulin-dependent diabetes. Several clinical trials using human embryonic stem cell (hESC)-derived β-like cells are currently underway, with encouraging preliminary results. Remaining challenges notwithstanding, these strategies are widely expected to reduce our reliance on human isolated islets for transplantation procedures, making cell therapies available to millions of diabetic patients. At the same time, advances in our understanding of pancreatic cell plasticity and the molecular mechanisms behind β-cell replication and regeneration have spawned a multitude of translational efforts aimed at inducing β-cell replenishment in situ through pharmacological means, thus circumventing the need for transplantation.

SCOPE OF REVIEW

We discuss here the current state of the art in hESC transplantation, as well as the parallel quest to discover agents capable of either preserving the residual mass of β-cells or inducing their proliferation, transdifferentiation or differentiation from progenitor cells.

MAJOR CONCLUSIONS

Stem cell-based replacement therapies in the mold of islet transplantation are already around the corner, but a permanent cure for type 1 diabetes will likely require the endogenous regeneration of β-cells aided by interventions to restore the immune balance. The promise of current research avenues and a strong pipeline of clinical trials designed to tackle these challenges bode well for the realization of this goal.

Efficacy of glucagon-like peptide-1 and estrogen dual agonist in pancreatic islets protection and pre-clinical models of insulin-deficient diabetes

We study the efficacy of a glucagon-like peptide-1 (GLP-1) and estrogen dual agonist (GLP1-E2) in pancreatic islet protection. GLP1-E2 provides superior protection from insulin-deficient diabetes induced by multiple low-dose streptozotocin (MLD-STZ-diabetes) and by the Akita mutation in mice than a GLP-1 monoagonist. GLP1-E2 does not protect from MLD-STZ-diabetes in estrogen receptor-α (ERα)-deficient mice and fails to prevent diabetes in Akita mice following GLP-1 receptor (GLP-1R) antagonism, demonstrating the requirement of GLP-1R and ERα for GLP1-E2 antidiabetic actions. In the MIN6 β cell model, GLP1-E2 activates estrogen action following clathrin-dependent, GLP-1R-mediated internalization and lysosomal acidification. In cultured human islet, proteomic bioinformatic analysis reveals that GLP1-E2 amplifies the antiapoptotic pathways activated by monoagonists. However, in cultured mouse islets, GLP1-E2 provides antiapoptotic protection similar to monoagonists. Thus, GLP1-E2 promotes GLP-1 and E2 antiapoptotic signals in cultured islets, but in vivo, additional GLP1-E2 actions in non-islet cells expressing GLP-1R are instrumental to prevent diabetes.

Menopausal hormone therapy and risk of cardiovascular events in women with prediabetes or type 2 diabetes: A pooled analysis of 2917 postmenopausal women

BACKGROUND AND AIMS

The effect of MHT on cardiovascular disease (CVD) risk among women with prediabetes or type 2 diabetes (PreDM or T2DM) is unclear. We examined the association between ever or early use MHT and CVD risk in postmenopausal women with PreDM or T2DM, and the potential modifying effect of race.

METHODS

2,917 postmenopausal women with PreDM or T2DM were pooled from 3 prospective CVD cohorts (the Atherosclerosis Risk in Communities, the Multi-Ethnic Study of Atherosclerosis, and the Jackson Heart Study). Ever (yes vs no) or early use of MHT (MHT initiated ≤5 vs > 5 years since menopause), and their associations with ischemic stroke, coronary heart disease (CHD), and atherosclerotic cardiovascular disease (ASCVD) were assessed using Cox proportional hazards models.

RESULTS

During a median follow-up of 15 years, 264 stroke, 484 CHD, and 659 ASCVD events were observed. In fully adjusted models, ever use of MHT was associated with reduced risk of stroke (hazard ratio 0.86, 95% CI 0.76-0.98), CHD (0.85, 0.74-0.98), and ASCVD (0.83, 0.73-0.95) in white women with PreDM or T2DM. Early use of MHT was associated with reduced risk of stroke (0.82, 0.72-0.95), CHD (0.85, 0.74-0.98), and ASCVD (0.82, 0.70-0.96) in the white group. No risk reduction with ever or early use of MHT was found for black women with PreDM or T2DM.

CONCLUSIONS

MHT is associated with statistically reduced CVD risk among white but not black women with PreDM or DM. Race is an effect modifier in the association between MHT use and CVD.

Prolonged Islet Allograft Function is Associated With Female Sex in Patients After Islet Transplantation

BACKGROUND

Islet transplantation (ITx) has proved to be effective in preventing severe hypoglycemia and improving metabolic control in selected subjects with type 1 diabetes. Long-term graft function remains a challenge. Estrogens have been shown to protect β cells from metabolic stresses and improve revascularization of transplanted human islets in the mouse. We aimed to evaluate the influence of sex in allograft survival of ITx recipients.

METHODS

We analyzed a retrospective cohort of ITx recipients (n = 56) followed-up for up to 20 years. Allograft failure was defined as a stimulated C-peptide <0.3 ng/mL during a mixed-meal tolerance test. Subjects were divided into recipients of at least 1 female donor (group 1) and recipients of male donors only (group 2).

RESULTS

Group 1 subjects (n = 25) were aged 41.5 ± 8.4 years and group 2 subjects (n = 22) 45.9 ± 7.3 years (P = 0.062). Female recipient frequency was 44.8% (n = 13) in group 1 and 55.2% (n = 16) in group 2 (P = 0.145). Group 2 developed graft failure earlier than group 1 (680 [286-1624] vs 1906 [756-3256] days, P = 0.038). We performed additional analyses on female recipients only from each group (group 1, n = 16; group 2, n = 20). Female recipients in group 1 exhibited prolonged allograft function compared with group 2, after adjustment for confounders (odds ratio, 28.6; 95% CI, 1.3-619.1; P < 0.05).

CONCLUSION

Recipients of islets from at least 1 female donor exhibited prolonged graft survival compared with recipients of islets from exclusively male donors. In addition, female recipients exhibited prolonged survival compared with male recipients following ITx of at least 1 female donor.

Metabolic Syndrome and Acute Respiratory Distress Syndrome in Hospitalized Patients With COVID-19

IMPORTANCE

Obesity, diabetes, and hypertension are common comorbidities in patients with severe COVID-19, yet little is known about the risk of acute respiratory distress syndrome (ARDS) or death in patients with COVID-19 and metabolic syndrome.

OBJECTIVE

To determine whether metabolic syndrome is associated with an increased risk of ARDS and death from COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter cohort study used data from the Society of Critical Care Medicine Discovery Viral Respiratory Illness Universal Study collected from 181 hospitals across 26 countries from February 15, 2020, to February 18, 2021. Outcomes were compared between patients with metabolic syndrome (defined as ≥3 of the following criteria: obesity, prediabetes or diabetes, hypertension, and dyslipidemia) and a control population without metabolic syndrome. Participants included adult patients hospitalized for COVID-19 during the study period who had a completed discharge status. Data were analyzed from February 22 to October 5, 2021.

EXPOSURES

Exposures were SARS-CoV-2 infection, metabolic syndrome, obesity, prediabetes or diabetes, hypertension, and/or dyslipidemia.

MAIN OUTCOMES AND MEASURES

The primary outcome was in-hospital mortality. Secondary outcomes included ARDS, intensive care unit (ICU) admission, need for invasive mechanical ventilation, and length of stay (LOS).

RESULTS

Among 46 441 patients hospitalized with COVID-19, 29 040 patients (mean [SD] age, 61.2 [17.8] years; 13 059 [45.0%] women and 15713 [54.1%] men; 6797 Black patients [23.4%], 5325 Hispanic patients [18.3%], and 16 507 White patients [57.8%]) met inclusion criteria. A total of 5069 patients (17.5%) with metabolic syndrome were compared with 23 971 control patients (82.5%) without metabolic syndrome. In adjusted analyses, metabolic syndrome was associated with increased risk of ICU admission (adjusted odds ratio [aOR], 1.32 [95% CI, 1.14-1.53]), invasive mechanical ventilation (aOR, 1.45 [95% CI, 1.28-1.65]), ARDS (aOR, 1.36 [95% CI, 1.12-1.66]), and mortality (aOR, 1.19 [95% CI, 1.08-1.31]) and prolonged hospital LOS (median [IQR], 8.0 [4.2-15.8] days vs 6.8 [3.4-13.0] days; P < .001) and ICU LOS (median [IQR], 7.0 [2.8-15.0] days vs 6.4 [2.7-13.0] days; P < .001). Each additional metabolic syndrome criterion was associated with increased risk of ARDS in an additive fashion (1 criterion: 1147 patients with ARDS [10.4%]; P = .83; 2 criteria: 1191 patients with ARDS [15.3%]; P < .001; 3 criteria: 817 patients with ARDS [19.3%]; P < .001; 4 criteria: 203 patients with ARDS [24.3%]; P < .001).

CONCLUSIONS AND RELEVANCE

These findings suggest that metabolic syndrome was associated with increased risks of ARDS and death in patients hospitalized with COVID-19. The association with ARDS was cumulative for each metabolic syndrome criteria present.

Acute estradiol and progesterone therapy in hospitalised adults to reduce COVID-19 severity: a randomised control trial

INTRODUCTION

As of November 2021, COVID-19 has killed more than 5 million people globally, including over 750 000 in the USA. Apart from corticosteroids, most available therapeutic options are at best marginally efficient in reducing disease severity and are extremely expensive. The systematic investigation of clinically approved drugs is a priority to determine what does mitigate disease severity. Oestradiol (E2) and progesterone (P4) produce a state of anti-inflammatory immune responses and immune tolerance, and enhanced antibody production. The goal of this trial is to evaluate the efficacy of a short E2 and P4 therapy, in addition to standard of care (SOC), in mitigating disease severity in COVID-19 hospitalised patients.

METHODS AND ANALYSIS

Phase 2, randomised, double blind, placebo-controlled, single-centre trial. Patients hospitalised for confirmed COVID-19, with scores 3-5 on the 9-point WHO ordinal scale are randomised between two arms: (1) Oestradiol cypionate intramuscular (IM) and micronised progesterone oral (PO), in addition to SOC, and (2) placebo, in addition to SOC. The primary outcome is the proportion of patients improving to scores 1 or 2 on the WHO scale through day 28. Secondary outcomes include length of hospital stay, duration of mechanical ventilation, cause of death, readmission rates, change in inflammatory biomarkers between admission and occurrence of primary endpoint, and adverse events. Study sample size will be up to 120 participants. The trial is currently recruiting subjects.

ETHICS AND DISSEMINATION

The sponsor of this study is the Center of Excellence in Sex-Based Biology & Medicine at Tulane University, New Orleans, Louisiana, USA. Ethical approval was obtained from the Tulane institutional review board on 14 May 2021. The study was reviewed by the US Food and Drug Administration and granted Investigational New Drug #152 499. Results of the study will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT04865029; Pre-results.

Early Menopause and Cardiovascular Disease Risk in Women With or Without Type 2 Diabetes: A Pooled Analysis of 9,374 Postmenopausal Women

OBJECTIVE

Early menopause may be associated with higher cardiovascular disease (CVD) risk. Type 2 diabetes mellitus (T2DM), coupled with early menopause, may result in even greater CVD risk in women. We examined CVD risk in women with early compared with normal-age menopause, with and without T2DM overall, and by race/ethnicity.

RESEARCH DESIGN AND METHODS

We pooled data from the Atherosclerosis Risk in Communities study, the Multi-Ethnic Study of Atherosclerosis, and the Jackson Heart Study. We included women with data on menopausal status, menopausal age, and T2DM, excluding pre- or perimenopausal women and those with prevalent CVD. Outcomes included incident coronary heart disease (CHD), stroke, heart failure (HF), and atherosclerotic cardiovascular disease (ASCVD) (CHD or stroke). We estimated the risk associated with early (<45 years) compared with normal-age menopause using Cox proportional hazards models. Covariates included age, race/ethnicity, education, BMI, blood pressure, cholesterol, smoking, alcohol consumption, antihypertensive medication, lipid-lowering medication, hormone therapy use, and pregnancy history.

RESULTS

We included 9,374 postmenopausal women for a median follow-up of 15 years. We observed 1,068 CHD, 659 stroke, 1,412 HF, and 1,567 ASCVD events. T2DM significantly modified the effect of early menopause on CVD risk. Adjusted hazard ratios for early menopause and the outcomes were greater in women with T2DM versus those without (CHD 1.15 [95% CI 1.00, 1.33] vs. 1.09 [1.03, 1.15]; stroke 1.21 [1.04, 1.40] vs. 1.10 [1.04, 1.16]; ASCVD 1.29 [1.09, 1.51] vs. 1.10 [1.04, 1.17]; HF 1.18 [1.00, 1.39] vs. 1.09 [1.03, 1.16]). The modifying effect of T2DM on the association between early menopause and ASCVD was only statistically significant in Black compared with White women.

CONCLUSIONS

Early menopause was associated with an increased risk for CVD in postmenopausal women. T2DM may further augment the risk, particularly in Black women.

Sex-biased islet β cell dysfunction is caused by the MODY MAFA S64F variant by inducing premature aging and senescence in males

A heterozygous missense mutation of the islet β cell-enriched MAFA transcription factor (p.Ser64Phe [S64F]) is found in patients with adult-onset β cell dysfunction (diabetes or insulinomatosis), with men more prone to diabetes than women. This mutation engenders increased stability to the unstable MAFA protein. Here, we develop a S64F MafA mouse model to determine how β cell function is affected and find sex-dependent phenotypes. Heterozygous mutant males (MafAS64F/+) display impaired glucose tolerance, while females are slightly hypoglycemic with improved blood glucose clearance. Only MafAS64F/+ males show transiently higher MafA protein levels preceding glucose intolerance and sex-dependent changes to genes involved in Ca2+ signaling, DNA damage, aging, and senescence. MAFAS64F production in male human β cells also accelerate cellular senescence and increase senescence-associated secretory proteins compared to cells expressing MAFAWT. These results implicate a conserved mechanism of accelerated islet aging and senescence in promoting diabetes in MAFAS64F carriers in a sex-biased manner.

Androgen-induced insulin resistance is ameliorated by deletion of hepatic androgen receptor in females

Androgen excess is one of the most common endocrine disorders of reproductive-aged women, affecting up to 20% of this population. Women with elevated androgens often exhibit hyperinsulinemia and insulin resistance. The mechanisms of how elevated androgens affect metabolic function are not clear. Hyperandrogenemia in a dihydrotestosterone (DHT)-treated female mouse model induces whole body insulin resistance possibly through activation of the hepatic androgen receptor (AR). We investigated the role of hepatocyte AR in hyperandrogenemia-induced metabolic dysfunction by using several approaches to delete hepatic AR via animal-, cell-, and clinical-based methodologies. We conditionally disrupted hepatocyte AR in female mice developmentally (LivARKO) or acutely by tail vein injection of an adeno-associated virus with a liver-specific promoter for Cre expression in AR^fl/fl mice (adLivARKO). We observed normal metabolic function in littermate female Control (AR^fl/fl ) and LivARKO (AR^fl/fl ; Cre^+/- ) mice. Following chronic DHT treatment, female Control mice treated with DHT (Con-DHT) developed impaired glucose tolerance, pyruvate tolerance, and insulin tolerance, not observed in LivARKO mice treated with DHT (LivARKO-DHT). Furthermore, during an euglycemic hyperinsulinemic clamp, the glucose infusion rate was improved in LivARKO-DHT mice compared to Con-DHT mice. Liver from LivARKO, and primary hepatocytes derived from LivARKO, and adLivARKO mice were protected from DHT-induced insulin resistance and increased gluconeogenesis. These data support a paradigm in which elevated androgens in females disrupt metabolic function via hepatic AR and insulin sensitivity was restored by deletion of hepatic AR.

SARS-CoV-2 infection of the pancreas promotes thrombofibrosis and is associated with new-onset diabetes

Evidence suggests an association between severe acute respiratory syndrome–cornavirus-2 (SARS-CoV-2) infection and the occurrence of new-onset diabetes. We examined pancreatic expression of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), the cell entry factors for SARS-CoV-2, using publicly available single-cell RNA sequencing data sets, and pancreatic tissue from control male and female nonhuman primates (NHPs) and humans. We also examined SARS-CoV-2 immunolocalization in pancreatic cells of SARS-CoV-2–infected NHPs and patients who had died from coronavirus disease 2019 (COVID-19). We report expression of ACE2 in pancreatic islet, ductal, and endothelial cells in NHPs and humans. In pancreata from SARS-CoV-2–infected NHPs and COVID-19 patients, SARS-CoV-2 infected ductal, endothelial, and islet cells. These pancreata also exhibited generalized fibrosis associated with multiple vascular thrombi. Two out of 8 NHPs developed new-onset diabetes following SARS-CoV-2 infection. Two out of 5 COVID-19 patients exhibited new-onset diabetes at admission. These results suggest that SARS-CoV-2 infection of the pancreas may promote acute and especially chronic pancreatic dysfunction that could potentially lead to new-onset diabetes.

Do Anti-androgens Have Potential as Therapeutics for COVID-19?

Coronavirus disease 2019 (COVID-19) is characterized by a gender disparity in severity, with men exhibiting higher hospitalization and mortality rates than women. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, infects cells following recognition and attachment of the viral spike glycoprotein to the angiotensin-converting enzyme 2 transmembrane protein, followed by spike protein cleavage and activation by cell surface transmembrane protease serine 2 (TMPRSS2). In prostate cancer cells, androgen acting on the androgen receptor increases TMPRSS2 expression, which has led to the hypothesis that androgen-dependent expression of TMPRSS2 in the lung may increase men's susceptibility to severe COVID-19 and that, accordingly, suppressing androgen production or action may mitigate COVID-19 severity by reducing SARS-CoV-2 amplification. Several ongoing clinical trials are testing the ability of androgen deprivation therapies or anti-androgens to mitigate COVID-19. This perspective discusses clinical and molecular advances on the rapidly evolving field of androgen receptor (AR) action on cell surface transmembrane protease serine 2 (TMPRSS2) expression and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and the potential effect of anti-androgens on coronavirus disease 2019 (COVID-19) severity in male patients. It discusses limitations of current studies and offers insight for future directions.

Endothelial cell infection and dysfunction, immune activation in severe COVID-19

Rationale: Pulmonary vascular endotheliitis, perivascular inflammation, and immune activation are observed in COVID-19 patients. While the initial SARS-CoV-2 infection mainly infects lung epithelial cells, whether it also infects endothelial cells (ECs) and to what extent SARS-CoV-2-mediated pulmonary vascular endotheliitis is associated with immune activation remain to be determined. Methods: To address these questions, we studied SARS-CoV-2-infected K18-hACE2 (K18) mice, a severe COVID-19 mouse model, as well as lung samples from SARS-CoV-2-infected nonhuman primates (NHP) and patient deceased from COVID-19. We used immunostaining, RNAscope, and electron microscopy to analyze the organs collected from animals and patient. We conducted bulk and single cell (sc) RNA-seq analyses, and cytokine profiling of lungs or serum of the severe COVID-19 mice. Results: We show that SARS-CoV-2-infected K18 mice develop severe COVID-19, including progressive body weight loss and fatality at 7 days, severe lung interstitial inflammation, edema, hemorrhage, perivascular inflammation, systemic lymphocytopenia, and eosinopenia. Body weight loss in K18 mice correlated with the severity of pneumonia, but not with brain infection. We also observed endothelial activation and dysfunction in pulmonary vessels evidenced by the up-regulation of VCAM1 and ICAM1 and the downregulation of VE-cadherin. We detected SARS-CoV-2 in capillary ECs, activation and adhesion of platelets and immune cells to the vascular wall of the alveolar septa, and increased complement deposition in the lungs, in both COVID-19-murine and NHP models. We also revealed that pathways of coagulation, complement, K-ras signaling, and genes of ICAM1 and VCAM1 related to EC dysfunction and injury were upregulated, and were associated with massive immune activation in the lung and circulation. Conclusion: Together, our results indicate that SARS-CoV-2 causes endotheliitis via both infection and infection-mediated immune activation, which may contribute to the pathogenesis of severe COVID-19 disease.

Sex disparities in COVID-19 outcomes of inpatients with diabetes: insights from the CORONADO study

OBJECTIVE

Male sex is one of the determinants of severe coronavirus diseas-e-2019 (COVID-19). We aimed to characterize sex differences in severe outcomes in adults with diabetes hospitalized for COVID-19.

METHODS

We performed a sex-stratified analysis of clinical and biological features and outcomes (i.e. invasive mechanical ventilation (IMV), death, intensive care unit (ICU) admission and home discharge at day 7 (D7) or day 28 (D28)) in 2380 patients with diabetes hospitalized for COVID-19 and included in the nationwide CORONADO observational study (NCT04324736).

RESULTS

The study population was predominantly male (63.5%). After multiple adjustments, female sex was negatively associated with the primary outcome (IMV and/or death, OR: 0.66 (0.49-0.88)), death (OR: 0.49 (0.30-0.79)) and ICU admission (OR: 0.57 (0.43-0.77)) at D7 but only with ICU admission (OR: 0.58 (0.43-0.77)) at D28. Older age and a history of microvascular complications were predictors of death at D28 in both sexes, while chronic obstructive pulmonary disease (COPD) was predictive of death in women only. At admission, C-reactive protein (CRP), aspartate amino transferase (AST) and estimated glomerular filtration rate (eGFR), according to the CKD-EPI formula predicted death in both sexes. Lymphocytopenia was an independent predictor of death in women only, while thrombocytopenia and elevated plasma glucose concentration were predictors of death in men only.

CONCLUSIONS

In patients with diabetes admitted for COVID-19, female sex was associated with lower incidence of early severe outcomes, but did not influence the overall in-hospital mortality, suggesting that diabetes mitigates the female protection from COVID-19 severity. Sex-associated biological determinants may be useful to optimize COVID-19 prevention and management in women and men.

Epigenetic Programming Reverses Cardiometabolic Dysfunctions and Modulates Hypothalamic Genes Involved in Oxidative Stress and Inflammation in Angiotensin II-Treated Male Mice

Cardiometabolic disease is a global health issue that affects millions of people worldwide. Environmental perinatal exposure affects the health outcomes of the offspring and determines their disease susceptibility later in life. Angiotensin-II (Ang-II) is a peptide known to cause vasoconstriction, elevated blood glucose levels and inflammation. Previously, we reported that perinatal exposure to a hypercaloric diet (HD) results in elevated blood pressure (BP), weight gain, fasting hyperglycemia and glucose intolerance only in male mice. In addition, subcutaneous infusion of a sub-pressor dose of Ang-II was associated with a normalization in fasting blood glucose levels and a reversal of glucose intolerance only in programmed male mice. We hypothesize that epigenetic programming blocks the deleterious effects of Ang-II by altering its inflammatory signaling pathway. C57BL6/J dams were fed HD or regular diet (RD) for 1 month before mating with RD-fed males. After weaning, offspring of HD dams (programmed) and of RD dams (controls) were maintained on RD until 3 months of age. Mice then underwent 24 h BP recording (telemetry) and were implanted with Ang-II osmotic pumps (200 ng/kg/min/2 weeks). BP (24 h) was recorded weekly for 2 weeks. Mice were then sacrificed and hypothalami were harvested for mRNA sequencing (Illumina NextSeq). Programmed mice had lower 24 h systolic BP levels compared to control males (area under the curve: 41844 ±263.2 vs. 44522 ±275.6; p<0.0001). For RNAseq analysis, data showed 62 differentially expressed genes (DEG) in programmed males compared to controls. Using iPathway analysis, we found that some of the DEG are correlated to cholinergic synapse pathway (p=0.005) and neuroactive ligand-receptor interaction pathway (p=0.003). Nicotinic acetylcholine alpha-7 receptor (Chrna7) gene, known for its anti-inflammatory and hypoglycemic effects was upregulated in programmed males (p=0.024). On the other hand, genes involved in metabolic pathways and oxidative stress were differentially expressed as well. Phospholipase A2 group 3 (Pla2g3) gene, known to be overexpressed in oxidative stress was downregulated in programmed males (p=0.04). Moreover, Thiosulfate sulfurtransferase (Tst) gene, an antioxidant enzyme and used as a marker for enhanced insulin sensitivity was upregulated (p=0.023) in programmed males. Interestingly, female mice did not show any changes in BP or gene expression between the two groups. In conclusion, perinatal exposure to HD alters the cardiovascular response to Ang-II possibly through the modulation of gene expression of Chrna7 gene and genes involved in oxidative stress. Future experiments will be investigating the signaling pathways used in epigenetic programming to affect inflammation and oxidative stress in male mice.

Sex differences in soluble prorenin receptor in patients with type 2 diabetes

Background

The soluble prorenin receptor (sPRR), a member of the renin-angiotensin system (RAS), is elevated in plasma of patients with preeclampsia, hypertension, chronic kidney disease (CKD), and type 2 diabetes. Our goal was to examine the relationship between sPRR and RAS activation to define whether sexual dimorphisms in sPRR might explain sex disparities in renal outcomes in patients with type 2 diabetes.

Methods

Two hundred sixty-nine participants were included in the study (mean age, 48 ± 16 years; 42% men, 58% women), including 173 controls and 96 subjects with type 2 diabetes. In plasma and urine, we measured sPRR, plasma renin activity (PRA), and prorenin. In the urine, we also measured angiotensinogen along with other biomarkers of renal dysfunction.

Results

Plasma sPRR and PRA were significantly higher in women with type 2 diabetes compared to men. In these women, plasma sPRR was positively correlated with PRA, age, and body mass index (BMI). In contrast, in men the sPRR in urine but not in plasma positively correlated with eGFR in urine, but negatively correlated with urine renin activity, plasma glucose, age, and BMI.

Conclusions

In patients with type 2 diabetes, sPRR contributes to RAS stimulation in a sex-dependent fashion. In diabetic women, increased plasma sPRR parallels the activation of systemic RAS; while in diabetic men, decreased sPRR in urine matches intrarenal RAS stimulation. sPRR might be a potential indicator of intrarenal RAS activation and renal dysfunction in men and women with type 2 diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13293-021-00374-3.

Gender Differences in Health Protective Behaviors During the COVID-19 Pandemic in Taiwan: An Empirical Study

INTRODUCTION

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection produces more severe symptoms and a higher mortality in men than in women. The role of biological sex in the immune response to SARS-CoV-2 is believed to explain this sex disparity. However, the contribution of gender factors that influence health protective behaviors and therefore health outcomes, remains poorly explored.

METHODS

We assessed the contributions of gender in attitudes towards the COVID-19 pandemic, using a hypothetical influenza pandemic data from the 2014 Taiwan Social Change Survey. Participants were selected through a stratified, three-stage probability proportional-to-size sampling from across the nation, to fill in questionnaires that asked about their perception of the hypothetical pandemic, and intention to adopt health protective behaviors.

RESULTS

A total of 1,990 participants (median age 45.92 years, 49% women) were included. Significant gender disparities (p<0.001) were observed. The risk perception of pandemic (OR=1.28, 95% CI=1.21-1.35, p<0.001), older age (1.06, 95%=1.05-1.07, p<0.001), female gender (OR = 1.18, 95% CI = 1.09□1.27, p<0.001), higher education (OR=1.10, 95% CI=1.06-1.13, p<0.001), and larger family size (OR=1.09, 95% CI=1.06-1.15, p<0.001) were positively associated with health protective behaviors. The risk perception of pandemic (OR=1.25, 95% CI=1.15-1.36), higher education (OR=1.07, 95% CI=1.02-1.13, p<0.05), being married (OR=1.17, 95% CI=1.01-1.36, p<0.05), and larger family size (OR=1.33, 95% CI=1.25-1.42, p<0.001), were positively associated with intention to receive a vaccine. However, female gender was negatively associated with intention to receive a vaccine (OR=0.85, 95% CI=0.75-0.90, p<0.01) and to comply with contact-tracing (OR=0.95, 95% CI=0.90-1.00, p<0.05) compared to men. Living with children was also negatively associated with intention to receive vaccines (OR=0.77, 95% CI=0.66-0.90, p<0.001).

CONCLUSION

This study unveils gender differences in risk perception, health protective behaviors, vaccine hesitancy, and compliance with contact-tracing using a hypothetical viral pandemic. Gender-specific health education raising awareness of health protective behaviors may be beneficial to prevent future pandemics.

Sex- and Gender-Based Pharmacological Response to Drugs

In humans, the combination of all sex-specific genetic, epigenetic, and hormonal influences of biologic sex produces different in vivo environments for male and female cells. We dissect how these influences of sex modify the pharmacokinetics and pharmacodynamics of multiple drugs and provide examples for common drugs acting on specific organ systems. We also discuss how gender of physicians and patients may influence the therapeutic response to drugs. We aim to highlight sex as a genetic modifier of the pharmacological response to drugs, which should be considered as a necessary step toward precision medicine that will benefit men and women. SIGNIFICANCE STATEMENT: This study discusses the influences of biologic sex on the pharmacokinetics and pharmacodynamics of drugs and provides examples for common drugs acting on specific organ systems. This study also discusses how gender of physicians and patients influence the therapeutic response to drugs.

Clinical characteristics and outcomes in women and men hospitalized for coronavirus disease 2019 in New Orleans

Objectives

Determine if sex differences exist in clinical characteristics and outcomes of adults hospitalized for coronavirus disease 2019 (COVID-19) in a US healthcare system.

Design

Case series study.

Setting and participants

Sequentially hospitalized adults admitted for COVID-19 at two tertiary care academic hospitals in New Orleans, LA, between 27 February and 15 July 2020.

Measures and outcomes

Measures included demographics, comorbidities, presenting symptoms, and laboratory results. Outcomes included intensive care unit admission (ICU), invasive mechanical ventilation (IMV), and in-hospital death.

Results

We included 776 patients (median age 60.5 years; 61.4% women, 75% non-Hispanic Black). Rates of ICU, IMV, and death were similar in both sexes. In women versus men, obesity (63.8 vs 41.6%, P < 0.0001), hypertension (77.6 vs 70.1%, P = 0.02), diabetes (38.2 vs 31.8%, P = 0.06), chronic obstructive pulmonary disease (COPD, 22.1 vs 15.1%, P = 0.015), and asthma (14.3 vs 6.9%, P = 0.001) were more prevalent. More women exhibited dyspnea (61.2 vs 53.7%, P = 0.04), fatigue (35.7 vs 28.5%, P = 0.03), and digestive symptoms (39.3 vs 32.8%, P = 0.06) than men. Obesity was associated with IMV at a lower BMI (> 35) in women, but the magnitude of the effect of morbid obesity (BMI ≥ 40) was similar in both sexes. COPD was associated with ICU (adjusted OR (aOR), 2.6; 95%CI, 1.5–4.3) and IMV (aOR, 1.8; 95%CI, 1.2–3.1) in women only. Diabetes (aOR, 2.6; 95%CI, 1.2–2.9), chronic kidney disease (aOR, 2.2; 95%CI, 1.3–5.2), elevated neutrophil-to-lymphocyte ratio (aOR, 2.5; 95%CI, 1.4–4.3), and elevated ferritin (aOR, 3.6; 95%CI, 1.7–7.3) were independent predictors of death in women only. In contrast, elevated D-dimer was an independent predictor of ICU (aOR, 7.3; 95%CI, 2.7–19.5), IMV (aOR, 6.5; 95%CI, 2.1–20.4), and death (aOR, 4.5; 95%CI, 1.2–16.4) in men only.

Conclusions

This study highlights sex disparities in clinical determinants of severe outcomes in COVID-19 patients that may inform management and prevention strategies to ensure gender equity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13293-021-00359-2.

Intracrine Testosterone Activation in Human Pancreatic β-Cells Stimulates Insulin Secretion

Testosterone (T) affects β-cell function in men and women. T is a prohormone that undergoes intracrine conversion in target tissues to the potent androgen dihydrotestosterone (DHT) via the enzyme 5α-reductase (5α-R) or to the active estrogen 17β-estradiol (E2) via the aromatase enzyme. Using male and female human pancreas sections, we show that the 5α-R type 1 isoform (SRD5A1) and aromatase are expressed in male and female β-cells. We show that cultured male and female human islets exposed to T produce DHT and downstream metabolites. In these islets, exposure to the 5α-R inhibitors finasteride and dutasteride inhibited T conversion into DHT. We did not detect T conversion into E2 from female islets. However, we detected T conversion into E2 in islets from two out of four male donors. In these donors, exposure to the aromatase inhibitor anastrozole inhibited E2 production. Notably, in cultured male and female islets, T enhanced glucose-stimulated insulin secretion (GSIS). In these islets, exposure to 5α-R inhibitors or the aromatase inhibitor both inhibited T enhancement of GSIS. In conclusion, male and female human islets convert T into DHT and E2 via the intracrine activities of SRD5A1 and aromatase. This process is necessary for T enhancement of GSIS.

Effect of conjugated estrogens and bazedoxifene on glucose, energy and lipid metabolism in obese postmenopausal women

OBJECTIVE

Combining conjugated estrogens (CE) with the selective estrogen receptor modulator bazedoxifene (BZA) is a novel, orally administered menopausal therapy. We investigated the effect of CE/BZA on insulin sensitivity, energy metabolism, and serum metabolome in postmenopausal women with obesity.

DESIGN

Randomized, double-blind, crossover pilot trial with washout was conducted at Pennington Biomedical Research Center. Eight postmenopausal women (age 50-60 years, BMI 30-40 kg/m2) were randomized to 8 weeks CE/BZA or placebo. Primary outcome was insulin sensitivity (hyperinsulinemic-euglycemic clamp). Secondary outcomes included body composition (DXA); resting metabolic rate (RMR); substrate oxidation (indirect calorimetry); ectopic lipids (1H-MRS); fat cell size, adipose and skeletal muscle gene expression (biopsies); serum inflammatory markers; and serum metabolome (LC/MS).

RESULTS

CE/BZA treatment produced no detectable effect on insulin sensitivity, body composition, ectopic fat, fat cell size, or substrate oxidation, but resulted in a non-significant increase in RMR (basal: P = 0.06; high-dose clamp: P = 0.08) compared to placebo. CE/BZA increased serum high-density lipoprotein (HDL)-cholesterol. CE/BZA also increased serum diacylglycerol (DAG) and triacylglycerol (TAG) species containing long-chain saturated, mono- and polyunsaturated fatty acids (FAs) and decreased long-chain acylcarnitines, possibly reflecting increased hepatic de novo FA synthesis and esterification into TAGs for export into very low-density lipoproteins, as well as decreased FA oxidation, respectively (P < 0.05). CE/BZA increased serum phosphatidylcholines, phosphatidylethanolamines, ceramides, and sphingomyelins, possibly reflecting the increase in serum lipoproteins (P < 0.05).

CONCLUSIONS

A short treatment of obese postmenopausal women with CE/BZA does not alter insulin action or ectopic fat but increases serum markers of hepatic de novo lipogenesis and TAG production.

Preclinical efficacy of the GPER-selective agonist G-1 in mouse models of obesity and diabetes

Human obesity has become a global health epidemic, with few safe and effective pharmacological therapies currently available. The systemic loss of ovarian estradiol (E2) in women after menopause greatly increases the risk of obesity and metabolic dysfunction, revealing the critical role of E2 in this setting. The salutary effects of E2 are traditionally attributed to the classical estrogen receptors ERα and ERβ, with the contribution of the G protein-coupled estrogen receptor (GPER) still largely unknown. Here, we used ovariectomy- and diet-induced obesity (DIO) mouse models to evaluate the preclinical activity of GPER-selective small-molecule agonist G-1 (also called Tespria) against obesity and metabolic dysfunction. G-1 treatment of ovariectomized female mice (a model of postmenopausal obesity) reduced body weight and improved glucose homeostasis without changes in food intake, fuel source usage, or locomotor activity. G-1-treated female mice also exhibited increased energy expenditure, lower body fat content, and reduced fasting cholesterol, glucose, insulin, and inflammatory markers but did not display feminizing effects on the uterus (imbibition) or beneficial effects on bone health. G-1 treatment of DIO male mice did not elicit weight loss but prevented further weight gain and improved glucose tolerance, indicating that G-1 improved glucose homeostasis independently of its antiobesity effects. However, in ovariectomized DIO female mice, G-1 continued to elicit weight loss, reflecting possible sex differences in the mechanisms of G-1 action. In conclusion, this work demonstrates that GPER-selective agonism is a viable therapeutic approach against obesity, diabetes, and associated metabolic abnormalities in multiple preclinical male and female models.

Aging, Male Sex, Obesity, and Metabolic Inflammation Create the Perfect Storm for COVID-19

Coronavirus disease 2019 (COVID-19) is a novel threat that seems to result from the collusion between a new pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and an existing pandemic of metabolic disease driven by obesity. This Perspective explores the evolving epidemiological, clinical, biological, and molecular evidence to propose an unfolding paradigm in which old age, chronic metabolic disease (such as obesity, type 2 diabetes, and metabolic syndrome), and male biological sex produce a deadly symbiosis of dysregulated immunometabolism and chronic systemic inflammation that intensifies virally induced hyperinflammation associated with SARS-CoV-2 infection. It is intended to inspire new research directions and stimulate funding in this field.

Estradiol, Progesterone, Immunomodulation, and COVID-19 Outcomes

Severe outcomes and death from the novel coronavirus disease 2019 (COVID-19) appear to be characterized by an exaggerated immune response with hypercytokinemia leading to inflammatory infiltration of the lungs and acute respiratory distress syndrome. Risk of severe COVID-19 outcomes is consistently lower in women than men worldwide, suggesting that female biological sex is instrumental in protection. This mini-review discusses the immunomodulatory and anti-inflammatory actions of high physiological concentrations of the steroids 17β-estradiol (E2) and progesterone (P4). We review how E2 and P4 favor a state of decreased innate immune inflammatory response while enhancing immune tolerance and antibody production. We discuss how the combination of E2 and P4 may improve the immune dysregulation that leads to the COVID-19 cytokine storm. It is intended to stimulate novel consideration of the biological forces that are protective in women compared to men, and to therapeutically harness these factors to mitigate COVID-19 morbidity and mortality.

Endocrine Significance of SARS-CoV-2's Reliance on ACE2

The current COVID-19 pandemic is the most disruptive event in the past 50 years, with a global impact on health care and world economies. It is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a coronavirus that uses angiotensin-converting enzyme 2 (ACE2) as an entry point to the cells. ACE2 is a transmembrane carboxypeptidase and member of the renin-angiotensin system. This mini-review summarizes the main findings regarding ACE2 expression and function in endocrine tissues. We discuss rapidly evolving knowledge on the potential role of ACE2 and SARS coronaviruses in endocrinology and the development of diabetes mellitus, hypogonadism, and pituitary and thyroid diseases.

Metabolic Syndrome and COVID-19 Mortality Among Adult Black Patients in New Orleans

OBJECTIVE

Coronavirus disease 2019 (COVID-19) mortality is high in patients with hypertension, obesity, and diabetes. We examined the association between hypertension, obesity, and diabetes, individually and clustered as metabolic syndrome (MetS), and COVID-19 outcomes in patients hospitalized in New Orleans during the peak of the outbreak.

RESEARCH DESIGN AND METHODS

Data were collected from 287 consecutive patients with COVID-19 hospitalized at two hospitals in New Orleans, LA from 30 March to 5 April 2020. MetS was identified per World Health Organization criteria.

RESULTS

Among 287 patients (mean age 61.5 years; female, 56.8%; non-Hispanic black, 85.4%), MetS was present in 188 (66%). MetS was significantly associated with mortality (adjusted odds ratio [aOR] 3.42 [95% CI 1.52-7.69]), intensive care unit (ICU) (aOR 4.59 [CI 2.53-8.32]), invasive mechanical ventilation (IMV) (aOR 4.71 [CI 2.50-8.87]), and acute respiratory distress syndrome (ARDS) (aOR 4.70 [CI 2.25-9.82]) compared with non-MetS. Multivariable analyses of hypertension, obesity, and diabetes individually showed no association with mortality. Obesity was associated with ICU (aOR 2.18 [CI, 1.25-3.81]), ARDS (aOR 2.44 [CI 1.28-4.65]), and IMV (aOR 2.36 [CI 1.33-4.21]). Diabetes was associated with ICU (aOR 2.22 [CI 1.24-3.98]) and IMV (aOR 2.12 [CI 1.16-3.89]). Hypertension was not significantly associated with any outcome. Inflammatory biomarkers associated with MetS, CRP, and lactate dehydrogenase (LDH) were associated with mortality (CRP [aOR 3.66] [CI 1.22-10.97] and LDH [aOR 3.49] [CI 1.78-6.83]).

CONCLUSIONS

In predominantly black patients hospitalized for COVID-19, the clustering of hypertension, obesity, and diabetes as MetS increased the odds of mortality compared with these comorbidities individually.

Sex and gender: modifiers of health, disease, and medicine

Clinicians can encounter sex and gender disparities in diagnostic and therapeutic responses. These disparities are noted in epidemiology, pathophysiology, clinical manifestations, disease progression, and response to treatment. This Review discusses the fundamental influences of sex and gender as modifiers of the major causes of death and morbidity. We articulate how the genetic, epigenetic, and hormonal influences of biological sex influence physiology and disease, and how the social constructs of gender affect the behaviour of the community, clinicians, and patients in the health-care system and interact with pathobiology. We aim to guide clinicians and researchers to consider sex and gender in their approach to diagnosis, prevention, and treatment of diseases as a necessary and fundamental step towards precision medicine, which will benefit men's and women's health.

Biological sex impacts COVID-19 outcomes

The current novel coronavirus disease 2019 (COVID-19) pandemic is revealing profound differences between men and women in disease outcomes worldwide. In the United States, there has been inconsistent reporting and analyses of male-female differences in COVID-19 cases, hospitalizations, and deaths. We seek to raise awareness about the male-biased severe outcomes from COVID-19, highlighting the mechanistic differences including in the expression and activity of angiotensin-converting enzyme 2 (ACE2) as well as in antiviral immunity. We also highlight how sex differences in comorbidities, which can be associated with both age and race, impact male-biased outcomes from COVID-19.

SUN-582 Effect of the Combination of Conjugated Estrogens and Bazedoxifene on Muscle and Serum Lipidome in Obese Postmenopausal Women: A Placebo-Controlled Randomized Pilot Trial

Background and Objectives: Menopause is characterized by estrogen deficiency and predisposes women to weight gain and metabolic disturbances including lipid abnormalities. Orally-administered estrogens increase high-density lipoprotein (HDL) and triglycerides (TG) cholesterol and decreases low-density lipoprotein (LDL) cholesterol levels. The increase in serum TGs is not well understood. The objective of this study was to assess the effect of CE/BZA on serum and skeletal muscle lipid species in obese postmenopausal women.

Methods: Randomized double-blind crossover pilot trial in 8 obese postmenopausal women (53± 3 years, BMI 35.7±3.2 kg/m²) assigned to 8 weeks of CE/BZA or placebo with 8 weeks washout in between. At the end of each 8-week treatment period, intrahepatic and skeletal muscle lipids were measured by proton magnetic resonance spectroscopy (¹H-MRS) while serum and skeletal muscle lipidomics were assayed by ultrahigh performance liquid chromatography/mass spectrometry (UHPLC/MS).

Results: No treatment differences were observed in intrahepatic lipid, soleus intramyocellular lipid (IMCL) or extramyocellular lipid (EMCL) as well as tibialis anterior IMCL or EMCL.

The serum metabolome and lipidome comprised a total of 2002 biochemicals. Treatment with CE/BZA was associated with higher levels of diacylglycerols (DAGs) and triacylglycerols (TAGs) composed of long-chain saturated fatty acids (SFA, palmitic C16:0 and arachidic C20:0), monounsaturated FAs (MUFA, palmitoleic C16:1, oleic C18:1 and ecosenoic C20:1), and polyunsaturated FAs (PUFA, linoleic C18:2, arachidonic C20:4, eicosapentaenoic C20:5, and docosahexaenoic C22:6) compared to placebo (all p<0.05). Treatment with CE/BZA was also associated with lower levels of several acylcarnitine species, which are markers of FA oxidation, including long-chain SFA (C14, C16 and C18), MUFA (C18:1 and C24:1) and PUFA (C18:2, C20:2 and C20:4). In addition, treatment with CE/BZA was associated with higher levels of phosphatidylcholines (PCs), phosphatidylinositols (PIs), phosphatidylethanolamines (PEs), sphingomyelins (SMs), and ceramides (CER), as well as lower levels of lysophophatidylcholines (LPCs). There were no treatment differences in carnitine or ketones levels. The skeletal muscle analysis comprised a total of 652 biochemicals, but unlike in serum, no significant treatment differences were observed in the skeletal muscle lipidome.

Conclusions: Our lipidomic analysis supports a model in which CE/BZA (and likely all oral estrogens) increases hepatic de novo FA synthesis and esterification into TAGs for export into TAG-rich very low-density lipoproteins, as well as decreased FA oxidation, respectively. Although CE/BZA treatment inhibits FA oxidation, it is not associated with hepatic lipid accumulation as measured by MRS, or skeletal muscle lipid accumulation measured by MRS and lipidomics.