Associations of Endogenous Estradiol and Testosterone Levels With Plaque Composition and Risk of Stroke in Subjects With Carotid Atherosclerosis

Carotid plaque CTA analysis in patients with initial and recurrent ischemic stroke

OBJECTIVES

Recurrent ischemic stroke leads to prolonged hospital stays, deterioration in functional outcomes, increased disability and mortality rates. The composition of plaques is closely related to the occurrence of stroke. Our aim was to explore differences in carotid plaque characteristics between patients with initial and recurrent ischemic stroke.

METHODS

A retrospective study was conducted on 208 anterior circulation stroke patients who had completed head and neck CT angiography (CTA) examinations. Patients were divided into initial cerebral infarction (ICI) group and recurrent cerebral infarction (RCI) group according to clinical and imaging data. The histological and morphological characteristics of the plaques were assessed by using VascuCAP software. The general demographic data, plaque characteristics, and serological indicators were compared between the two groups. Then, the association between plaque characteristics were investigated. To investigate the contribution of plaque characteristics for predicting the risk of stroke recurrence, we have constructed multivariate logistic regression models with plaque characteristics and blood lipid level parameters.

RESULTS

There were significant differences in total carotid plaque volume (P = 0.002) between the ICI and RCI groups. The volume and percentage of Intraplaque Hemorrhage (IPH) and calcification (CALC) in the RCI group were significantly higher than those in the ICI group (P < 0.05). There were also statistically significant differences in IPH volume (P=＜0.001)and IPH percentage (P＜0.001)between the symptomatic and asymptomatic sides in the RCI group. In the ICI group, the difference in the maximum stenosis of the carotid artery lumen was statistically significant between the 2 sides (P = 0.025). The total cholesterol (P = 0.024) and triglyceride levels (P = 0.049) was significantly larger in the ICI group than in the RCI group. Further, there is a significant negative correlation between the volumes and percentages of IPH and CALC in the ICI group (volume, r = -0.225, P = 0.021; percentage, r = -0.293, P = 0.002). In addition, IPH volume and percentage were independent predictors in the logistic model with combined features of plaque volume, plaque percentage and blood lipid level (AUC = 0.755, 95 %CI 0.690-0.820).

CONCLUSION

The volume of total carotid plaque and IPH were significantly different between the ICI group and RCI group. The IPH volume and percentage on the symptomatic side of the RCI group were higher than those on the asymptomatic side. IPH has important indicative significance in identifying patients at risk of recurrent stroke.

ABBREVIATIONS

CTA, computed tomography angiography; ICI, initial cerebral infarction; RCI, recurrent cerebral infarction; IPH, intraplaque hemorrhage; CALC, calcification; AUC, area under the curve; CI, confidence interval.

Associations between testosterone and knee and hand osteoarthritis among males and females from the general population

PURPOSE

The aim of this study was to examine the relationship between testosterone levels (total and free) and the prevalence, incidence and progression of radiographic osteoarthritis (OA) and chronic pain outcomes in the knee and hand joints.

METHODS

This study is embedded in the Rotterdam Study cohort, a population-based prospective study with participants aged 45 and older. The association between testosterone levels and OA was tested in more than 8600 individuals, using generalized linear models and generalized estimating equations models, adjusting for age, body mass index (BMI), lifestyle factors and co-morbidities.

RESULTS

Higher total testosterone (Relative Risk [RR] 0.84, 95% Confidence Interval [CI] 0.69-1.00) and higher free testosterone (RR 0.85, 95% CI 0.70-1.00) were significantly associated with a lower prevalence of radiographic knee OA in females, but not significant in males. Higher free testosterone was significantly associated with lower incidence of chronic knee pain (CKP) in females (RR 0.85, 95% CI 0.71-0.98), but not in males. In contrast, higher free testosterone (RR 1.07, 95% CI 1.02-1.11) and total testosterone (RR 1.08, 95% CI 1.03-1.13) were significantly associated with higher severity of hand OA in males, but not in females. These associations were independent of BMI, other lifestyle factors, co-morbidities and years since menopause.

CONCLUSIONS

Our findings suggest a protective effect of free testosterone for CKP only in females. Future replication of our findings is needed in prospective cohort studies.

Quantitative correlation between carotid or lower limb atherosclerosis and coronary heart disease: a retrospective observational study

Background

Early diagnosis and intervention are key for the treatment of coronary heart disease (CHD). Ultrasound is used to assess risk stratification in patients with coronary artery disease. However, few studies quantify the relationship between carotid or lower limb atherosclerosis and coronary revascularization. The purpose of this study is to demonstrate that the semi-quantitative degree of atherosclerosis in the neck or lower extremity vessels can predict the need for coronary revascularization, thereby establishing a predictive model for coronary revascularization based on peripheral vascular disease.

Methods

Patients who underwent coronary angiography and peripheral vascular ultrasound were randomly selected for semi-quantitative analysis of the degree of coronary artery and peripheral vascular stenosis. Data from 306 patients were collected.

Results

The semiquantitative score, grade score and lower limb score from vascular ultrasound were positively correlated with the Gensini score of coronary artery lesions. The semi-quantitative score (score = 2) predicted the sensitivity and specificity for coronary revascularization at 83.74% and 61.72%, respectively. The graded score (score = 2) predicted the sensitivity and specificity for coronary revascularization at 77.24% and 72.13%, respectively. The lower extremity score (score = 3) predicted the sensitivity and specificity for coronary revascularization at 90.24% and 54.55%, respectively.

Conclusions

Carotid semiquantitative scores, grade scores, and lower limb scores are predictive factors for the need for coronary revascularization and can serve as auxiliary examinations for the early diagnosis of coronary artery disease.

Endogenous sex hormone levels are associated with the revised Framingham Stroke Risk Profile in postmenopausal women: a longitudinal study in a Swedish cohort

BACKGROUND

Endogenous sex hormones in postmenopausal women have been associated with risk of cardiovascular diseases. The aim of this study was to determine the association between endogenous sex hormones and the revised Framingham Stroke Risk Profile (rFSRP) in postmenopausal women.

METHODS

This is an observational cross-sectional study on the Vara-Skövde cohort, a Swedish population-based study for longitudinal surveillance of the development and progress of type 2 diabetes and hypertension. The participants were physically examined in 2002-2005 and sex hormones were analysed with liquid chromatography-tandem mass spectrometry assay (LC-MS/MS). Women who were ≥55 years old, with estradiol levels below 20 pg/mL, not using hormonal therapy, and with no self-reported history of stroke, were included (N = 133). The outcome variable was rFSRP. Regression analyses of log-transformed rFSRP were fitted against levels of sex hormones (17-α-OH-progesterone, estrone, estradiol, progesterone, dihydrotestosterone, dehydroepiandrosterone, testosterone and androstenedione), adjusting for body mass index (BMI) or waist-to-hip ratio (WHR), C-reactive protein (CRP) and cholesterol level.

RESULTS

Levels of estrone and estradiol were positively associated with rFSRP in the crude model (estrone β = 0.208, 95% CI = 0.081;0.336, P = 0.002; estradiol β = 0.170, CI = 0.034;0.305, P = 0.015). Adjustments for BMI revealed significant positive associations between progesterone (β = 0.155 95% CI = 0.025;0.285, P = 0.020), estrone (β = 0.167, 95% CI = 0.037;0.297, P = 0.013) and 17-α-OH-progesterone (β = 0.146, 95% CI = 0.014; 0.277, P = 0.030) and rFSRP, and adjustments for WHR revealed a significant positive association between testosterone and rFSRP (β = 0.152, CI = 0.026;0.278, p = 0.018).

CONCLUSIONS

Increase of estrone was associated with higher rFSRP, also in the fully adjusted model, whereas progesterone, 17-α-OH-progesterone and testosterone were significant only in the models adjusting for BMI and WHR respectively. Larger studies studying stroke events are warranted to confirm these findings.

CLINICAL TRIAL NUMBER

Not applicable.

The causal relationship between steroid hormones and risk of stroke: evidence from a two-sample Mendelian randomization study

It is unclear how steroid hormones contribute to stroke, and conducting randomized controlled trials to obtain related evidence is challenging. Therefore, Mendelian randomization (MR) technique was employed in this study to examine this association. Through genome-wide association meta-analysis, the genetic variants of steroid hormones, including testosterone/17β-estradiol (T/E2) ratio, aldosterone, androstenedione, progesterone, and hydroxyprogesterone, were acquired as instrumental variables. Analysis was done on the impact of these steroid hormones on the risk of stroke subtypes. The T/E2 ratio was associated to an elevated risk of small vessel stroke (SVS) according to the inverse variance weighted approach which was the main MR analytic technique (OR, 1.23, 95% CI: 1.05-1.44, p = 0.009). These findings were solid since no heterogeneity nor horizontal pleiotropy were found. The causal association between T/E2 and SVS was also confirmed in the replication study (p = 0.009). Nevertheless, there was no proof that other steroid hormones increased the risk of stroke. According to this study, T/E2 ratio and SVS are causally related. However, strong evidence for the impact of other steroid hormones on stroke subtypes is still lacking. These findings may be beneficial for developing stroke prevention strategies from steroid hormones levels.

Sex-Related Outcomes in Asymptomatic Carotid Artery Stenosis Undergoing Carotid Endarterectomy

INTRODUCTION

This study aims to retrospectively analyze the perioperative and long-term outcomes of carotid endarterectomy (CEA) performed in asymptomatic patients, stratifying the results by sex.

METHODS

Data on CEAs performed from January 2009 to December 2020 at our institution were collected. A neurologic evaluation was conducted 30 d after surgery to assess the occurrence of neurological events. Instrumental evaluations using Doppler ultrasound were performed within the first 3 mo, at 12 mo, and annually thereafter. The primary endpoints were perioperative mortality, major neurological events, and major complications. Secondary endpoints included long-term overall survival, stroke-free survival, absence of neurological symptoms, and absence of significant (>70%) restenosis.

RESULTS

Two thousand one hundred ninety-four CEAs were performed in asymptomatic patients, with 758 females and 1436 males. There were no differences in perioperative outcomes between the two groups. In the multivariate analysis, female sex was found to be a protective factor for the risk of 30-d stroke (hazard ratio: 0.2; 95% confidence interval: 0.04-0.9; P = 0.05). At a median follow-up of 24 mo, the estimated 10-y overall and stroke-free survival rates were 77.6% in males versus 62.7% in females, P = 0.2 and 70% in males versus 61% in females, P = 0.1, respectively. Also the rates of significant restenosis did not differ between males and females (82.2% versus 87.7%, P = 0.5).

CONCLUSIONS

This study suggests that female sex, by itself, does not represent a risk factor for adverse outcomes after carotid surgery and it appears to be protective in the first 30 d following surgery.

Premature Acute Myocardial Infarction Treated With Invasive Revascularization: Comparing STEMI With NSTEMI in a Population-Based Study of Young Patients

BACKGROUND

Acute myocardial infarction (AMI) usually presents in older populations, in which there are established demographic and outcome differences for ST-elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI). No similar comparisons for AMI in the young population exist.

METHODS

We compared all index NSTEMI and STEMI hospitalizations in young (18-45 years) patients who required revascularization in Alberta, Canada. Outcomes were survival to discharge, and a composite of heart failure hospitalization, cardiac arrest hospitalization, and all-cause mortality at 1 and 5 years.

RESULTS

There were 1679 patients included with an index AMI who required revascularization: 655 (39.0%) NSTEMI and 1024 (61.0%) STEMI. The population was disproportionately male (86%), particularly in STEMI patients (87.3%). Marked dyslipidemia (35%) and active smoking (42%) were common, with similar rates among groups. Percutaneous coronary intervention was used in 98.7% of STEMI and 91.5% of NSTEMI patients (P < 0.001), with the remainder who underwent surgical revascularization. The in-hospital mortality rate during index AMI was higher in STEMI compared with NSTEMI patients (1.7% vs 0%; P < 0.001). The rates of the composite outcome were similar for both groups at 1 and 5 years of follow-up in patients who survived to index hospital discharge. After adjusting for sex, age, heart failure and/or cardiac arrest at index AMI, outcomes remained similar among groups at 1 and 5 years.

CONCLUSIONS

In young patients with AMI, STEMI was a disproportionately male phenomenon and associated with higher mortality at index hospitalization. One-year and 5-year outcomes were similar among STEMI and NSTEMI patients in those discharged alive at index AMI. Smoking and dyslipidemia appear to be major risk factors in the young.

Estradiol Level as a Risk Factor for Cardiovascular Endpoints in Men: A Systematic Review

Cardiovascular disease is a major cause of higher mortality of middle-aged and elderly males in comparison to women. Sex hormones action on cardiovascular system is the most likely explanation of this differences. Nevertheless, estradiol and cardiovascular disease relationship is still unclear. The authors conducted a systematic review to identify the association of endogenous estradiol with cardiovascular endpoints in men. Articles were identified by a MedLine search (1961 — July 2023) and citation tracking. No evidence synthesis was conducted. 24 eligible articles were found. In 10 studies no association of sex hormones and endpoints was found. In 7 studies there was an association of testosterone and endpoints, but no significant results for estradiol. 7 studies have reported significant association of estradiol and cardiovascular endpoints. Inconsistency in evidence is significantly influenced by differences between studies in patient age, follow-up, researched endpoints and quality of estradiol essay. Over 40% of published studies, that researched the association of estradiol and death, found such a link. However, existing body of literature is largely heterogenous and doesn’t provide definite evidence for a pronounced net effect of estradiol on cardiovascular health in general men population. The present systematic review hints, that endogenous estradiol could be linked with cardiovascular risks in white men of young and middle age.

The complementary roles of iron and estrogen in menopausal differences in cardiometabolic outcomes

Biological hormonal changes are frequently cited as an explanatory factor of sex and menopause differences in cardiometabolic diseases (CMD) and its associated risk factors. However, iron metabolism which varies between sexes and among women of different reproductive stages could also play a role. Recent evidence suggest that iron may contribute to CMD risk by modulating oxidative stress pathways and inflammatory responses, offering insights into the mechanistic interplay between iron and CMD development. In the current review, we provide a critical appraisal of the existing evidence on sex and menopausal differences in CMD, discuss the pitfall of current estrogen hypothesis as sole explanation, and the emerging role of iron in CMD as complementary pathway. Prior to menopause, body iron stores are lower in females as compared to males, but the increase during and after menopause, is tandem with an increased CMD risk. Importantly, basic science experiments show that an increased iron status is related to the development of type 2 diabetes (T2D), and different cardiovascular diseases (CVD). While epidemiological studies have consistently reported associations between heme iron intake and some iron biomarkers such as ferritin and transferrin saturation with the risk of T2D, the evidence regarding their connection to CVD remains controversial. We delve into the factors contributing to this inconsistency, and the limitation of relying on observational evidence, as it does not necessarily imply causation. In conclusion, we provide recommendations for future studies on evaluating the potential role of iron in elucidating the sex and menopausal differences observed in CMD.

Sex hormone-binding globulin exerts sex-related causal effects on lower extremity varicose veins: evidence from gender-stratified Mendelian randomization

Background

The association between serum sex hormones and lower extremity varicose veins has been reported in observational studies. However, it is unclear whether the association reflects a causal relationship. Besides, serum sex hormone-binding globulin (SHBG) has been rarely studied in lower extremity varicose veins. Here, we aim to investigate the association between serum levels of SHBG, testosterone, and estradiol and the risk of lower extremity varicose veins using Mendelian randomization (MR).

Methods

We obtained genome-wide association study summary statistics for serum SHBG levels with 369,002 European participants, serum testosterone levels with 424,907 European participants, serum estradiol levels with 361,194 European participants, and lower extremity varicose veins with 207,055 European participants. First, a univariable MR was performed to identify the causality from SHBG and sex hormone levels to lower extremity varicose veins with several sensitivity analyses being performed. Then, a multivariable MR (MVMR) was performed to further assess whether the causal effects were independent. Finally, we performed a gender-stratified MR to understand the role of genders on lower extremity varicose veins.

Results

Genetically predicted higher serum SHBG levels significantly increased the risk of lower extremity varicose veins in the univariable MR analysis (OR=1.39; 95% CI: 1.13-1.70; P=1.58×10-3). Sensitivity analyses and MVMR (OR=1.50; 95% CI:1.13-1.99; P=5.61×10-3) verified the robustness of the causal relationships. Gender-stratified MR revealed that higher serum SHBG levels were associated with lower extremity varicose veins in both sexes. However, the OR of serum SHBG levels on lower extremity varicose veins risk in females (OR=1.51; 95% CI: 1.23-1.87; P=1.00×10-4) was greater than in males (OR=1.26; 95% CI: 1.04-1.54; P=1.86×10-2).

Conclusions

Serum SHBG levels are positively related to lower extremity varicose veins risk in both sexes, especially in females. This may partly explain the higher prevalence of varicose vines among females.

Sex Differences in Neurological Emergencies Presenting to Multiple Urban Level 1 Trauma Centers

Previous studies have suggested that there are sex differences in the treatment and outcome of neurological emergencies; however, research identifying the role these sex differences play in the management of neurological emergencies is lacking. More knowledge of the way sex factors into the pathophysiology of neurological emergencies will be helpful in improving outcomes for these patients. The aim of this cross-sectional study was to assess the prevalence and management of neurological emergencies while evaluating sex differences in the diagnosis and treatment of these emergencies. We analyzed a cohort of 530 adult patients from four level 1 trauma centers over a period of 4 weeks who had a chief complaint of a neurological emergency, including seizures, cerebrovascular events, headache disorders, traumatic brain injuries, and central nervous system infections. Among patients with neurological emergencies, a significantly lower proportion of female patients underwent neurosurgery and were admitted to the intensive care unit compared to male patients, but there were no significant differences between sexes in the time of symptom onset, type of hospital transportation, amount of neuroimaging performed, admission rates, hospital length of stay, and disposition from the emergency department. Although female patients were more likely to have a chief complaint of headache compared to traumatic injuries in male patients, this was not statistically significant. A significantly higher proportion of female patients had health insurance coverage than male patients.

Early menopause and cardiovascular risk factors: a cross-sectional and longitudinal study

OBJECTIVE

The aim of the study is to evaluate the cross-sectional and longitudinal association of early natural menopause with changes in cardiovascular risk factors (CVRFs).

METHODS

Postmenopausal women from the Swiss CoLaus study, reporting age at natural menopause (ANM) and having CVRFs measurements (blood lipids, blood pressure, glucose, homeostatic model assessment for insulin resistance [HOMA-IR], and inflammatory markers) at baseline (2003-2006) and first follow-up (2009-2012) were eligible for analysis. Age at natural menopause was analyzed as a continuous variable and in categories (ANM <45 and ≥45 y old). Linear regression analysis and linear mixed models were used to assess whether ANM is associated cross-sectionally and longitudinally with changes in CVRFs. Models were adjusted for demographic characteristics, lifestyle-related factors, time since menopause, medication, and clinical conditions.

RESULTS

We analyzed 981 postmenopausal women. The cross-sectional analysis showed that women with ANM younger than 45 years had lower diastolic blood pressure (β = -3.76 mm Hg; 95% confidence interval [CI] = -5.86 to -1.65) compared with women whose ANM was 45 years or older. In the longitudinal analysis, ANM younger than 45 years was associated with changes in log insulin (β = 0.26; 95% CI = 0.08 to 0.45) and log homeostatic model assessment for insulin resistance levels (β = 0.28; 95% CI = 0.08 to 0.48). No associations were found between ANM and other CVRFs.

CONCLUSIONS

Early menopause may be associated with changes in glucose metabolism, while it may have little to no impact on other CVRFs. Larger longitudinal studies are needed to replicate our findings.

Sex Differences in Carotid Atherosclerosis: A Systematic Review and Meta-Analysis

BACKGROUND

Over the last decades, several individual studies on sex differences in carotid atherosclerosis have been performed covering a wide range of plaque characteristics and including different populations. This systematic review and meta-analysis aims to summarize previously reported results on sex differences in carotid atherosclerosis and present a roadmap explaining next steps needed for implementing this knowledge in clinical practice.

METHODS

We systematically searched PubMed, Embase, Web of Science, Cochrane Central, and Google Scholar for eligible studies including both male and female participants reporting prevalence of imaging characteristics of carotid atherosclerosis and meta-analyzed these studies. Studies had to report at least the following: (1) calcifications; (2) lipid-rich necrotic core; (3) intraplaque hemorrhage; (4) thin-or-ruptured fibrous cap; (5) plaque ulceration; (6) degree of stenosis; (7) plaque size; or (8) plaque inflammation. We prespecified which imaging modalities had to be used per plaque characteristic and excluded ultrasonography.

RESULTS

We included 42 articles in our meta-analyses (ranging from 2 through 23 articles per plaque characteristic). Men had more frequently a larger plaque compared to women and, moreover, had more often plaques with calcifications (odds ratio=1.57 [95% CI, 1.23-2.02]), lipid-rich necrotic core (odds ratio=1.87 [95% CI, 1.36-2.57]), and intraplaque hemorrhage (odds ratio=2.52 [95% CI, 1.74-3.66]), or an ulcerated plaque (1.81 [95% CI, 1.30-2.51]). Furthermore, we found more pronounced sex differences for lipid-rich necrotic core in symptomatic opposed to asymptomatic participants.

CONCLUSIONS

In this systematic review and meta-analysis, we demonstrate convincing evidence for sex differences in carotid atherosclerosis. All kinds of plaque features-plaque size, composition, and morphology-were more common or larger in men compared to women. Our results highlight that sex is an important variable to include in both study design and clinical-decision making. Further investigation of sex-specific stroke risks with regard to plaque composition is warranted.

Sex steroids and sex steroid-binding globulin levels amongst middle-aged and elderly men and women from general population

BACKGROUND AND AIMS

Availability of age- and sex-specific reference values for sex steroids and sex steroid-binding globulin (SHBG) levels allows for appropriate interpretation of research findings and their clinical applications. We report the sex-specific distribution and reference levels of sex steroids, including total estradiol, total testosterone and (calculated) free androgen index (cFAI), SHBG and other androgens dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS) and androstenedione across age.

METHODS

Using data from 3291 participants from the prospective population-based Rotterdam Study (2006-2008), we visualised the distribution of sex steroids and SHBG levels by calculating and depicting the 5th, 25th, 50th, 75th and 95th percentiles per year and per age-year across 5-year age bands to provide reference value ranges in men and women. Total estradiol and SHBG were measured using automated immunoassay and androgens using liquid chromatography-mass spectrometry (LC-MS/MS).

RESULT

Mean age was 56.8 (range 45.6-79.9) years in men and 56.9 (range 45.7-79.9) years in women. Amongst men, total estradiol and SHBG showed an increasing trend from 45 years onwards. In women, total estradiol and SHBG showed a decreasing trend from 45 years until the age of 60. From 60 years onwards, SHBG showed an increasing trend. For total testosterone, a clear declining trend was observed amongst men but not women. Other androgens showed a similar decreasing trend in both sexes from 45 years onwards.

DISCUSSION AND CONCLUSION

Our study underlines sex-specific trends in sex steroids and SHBG levels with ageing. This warrants taking into account sex- and age-specific reference values for sex steroids and SHBG when investigating their impact on health outcomes to prevent controversial results and allow for their appropriate clinical application.

The mediating role of plasma microRNAs in the association of phthalates exposure with arterial stiffness: A panel study

Phthalates exposure has been reported to be linked with arterial stiffness. However, the biological mechanisms underlying this association remain unclear. We conducted a panel study using 338 paired urine-blood samples by repeated measurements of 123 adults across 3 seasons to assess the potential mediating role of plasma microRNAs (miRNAs) in the association of phthalates exposure with arterial stiffness. We measured 10 urinary phthalate metabolites by gas chromatography-tandem mass spectrometry (GC-MS/MS) and 5 candidate arterial stiffness-related miRNAs (miR-146a, miR-222, miR-125b, miR-126, and miR-21) in plasma by real-time PCR. Arterial stiffness parameters including brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) were determined in health examinations during each visit. Linear mixed-effect (LME) models revealed that mono-methyl phthalate (MMP), mono-iso-butyl phthalate (MiBP), mono-n-butyl phthalate (MBP), mono-n-octyl phthalate (MOP), and mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP) were significantly associated with one or more of the 5 plasma miRNAs (all P_FDR < 0.05). Based on weighted quantile sum (WQS) regression, we found positive associations of phthalate metabolites mixture with miR-146a, miR-125b, and miR-222, and individual MMP and MBP were the major contributors. Additionally, miR-146a was inversely related to ABI. Mediation analysis further indicated that miR-146a mediated 31.6% and 21.3% of the relationships of MMP and MiBP with ABI, respectively. Our findings suggested that certain phthalates exposure was related to plasma miRNAs alterations in a dose-response manner and miR-146a might partly mediate phthalate-associated ABI reduction.

An LC-MS/MS Methodological Framework for Steroid Hormone Measurement from Human Serum

Estrogens and androgens are important regulators of sexual development and physiological processes in men and women, acting on numerous organs throughout the body. Moreover, they can contribute to a variety of pathologies, including osteoporosis, cancer, and cardiovascular and neurologic diseases. Analysis of estrogens and androgens in biological samples has been commonly performed using immunoassays for many years. However, these assays are suboptimal, as there is cross-reactivity with similar analytes, and they have moderate specificity and sensitivity. Thus, there is a clinical need to develop highly sensitive and specific methods for the accurate measurement of estrogen and androgen concentrations. Herein, we describe the development of three liquid chromatography coupled tandem mass spectrometry-based methods that incorporate the use of a Triple Quadrupole Mass Spectrometer for quantitative measurement of endogenous concentrations of various steroid hormones in human serum samples: (1) the simultaneous measurement of testosterone, androstenedione, and cortisol, (2) dehydroepiandrosterone (DHEA), and (3) 17β-estradiol (E₂). The use of derivatizing reagents, Girard's reagent P and dansyl chloride, allowed for significant gains in sensitivity in the analysis of DHEA and E2, respectively, relative to the underivatized analyte. These procedures proved efficient and adequately sensitive for steroid hormone analysis in extracted patient sera samples from older men and postmenopausal women, providing reliable data down to low nanogram/ml and sub-nanogram/ml levels. Moreover, utilizing the combination of highly specific mass transitions associated with these analytes and their respective internal deuterated standards provided a high degree of specificity to the identity of these hormones.

The Effects of Menopause Hormone Therapy on Lipid Profile in Postmenopausal Women: A Systematic Review and Meta-Analysis

Importance: The incidence of dyslipidemia increases after menopause. Menopause hormone therapy (MHT) is recommended for menopause related disease. However, it is benefit for lipid profiles is inconclusive. Objective: To conduct a systematic review and meta-analysis of randomized controlled trials to evaluate the effects of MHT on lipid profile in postmenopausal women. Evidence Review: Related articles were searched on PubMed/Medline, EMBASE, Web of Science, and Cochrane Library databases from inception to December 2020. Data extraction and quality evaluation were performed independently by two reviewers. The methodological quality was assessed using the "Cochrane Risk of Bias checklist". Results: Seventy-three eligible studies were selected. The results showed that MHT significantly decreased the levels of TC (WMD: -0.43, 95% CI: -0.53 to -0.33), LDL-C (WMD: -0.47, 95% CI: -0.55 to -0.40) and LP (a) (WMD: -49.46, 95% CI: -64.27 to -34.64) compared with placebo or no treatment. Oral MHT led to a significantly higher TG compared with transdermal MHT (WMD: 0.12, 95% CI: 0.04-0.21). The benefits of low dose MHT on TG was also concluded when comparing with conventional-dose estrogen (WMD: -0.18, 95% CI: -0.32 to -0.03). The results also showed that conventional MHT significantly decreased LDL-C (WMD: -0.35, 95% CI: -0.50 to -0.19), but increase TG (WMD: 0.42, 95%CI: 0.18-0.65) compared with tibolone. When comparing with the different MHT regimens, estrogen (E) + progesterone (P) regimen significantly increased TC (WMD: 0.15, 95% CI: 0.09 to 0.20), LDL-C (WMD: 0.12, 95% CI: 0.07-0.17) and Lp(a) (WMD: 44.58, 95% CI:28.09-61.06) compared with estrogen alone. Conclusion and Relevance: MHT plays a positive role in lipid profile in postmenopausal women, meanwhile for women with hypertriglyceridemia, low doses or transdermal MHT or tibolone would be a safer choice. Moreover, E + P regimen might blunt the benefit of estrogen on the lipid profile. Clinical Trial Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42018092924], identifier [No. CRD42018092924].

High Prevalence of Asymptomatic Intracranial Atherosclerosis in Elder Women With Tubal Ligation: Result From a Community-Based Study in Shandong, China

Background

In addition to traditional cardiovascular risk factors, gender-specific factors may also contribute to intracranial atherosclerosis. This study aimed to comprehensively investigate the association between asymptomatic intracranial atherosclerosis (aICAS) and menstrual or reproductive history (MRH), namely, menstruation, pregnancy, childbirth, menopause, and contraception.

Methods

Participants in this study were selected from the Kongcun town aICAS study. MRH was collected through structured case report forms, in which menarche age, menstrual regularity, dysmenorrhea, number of pregnancies, number of childbirths, age of first pregnancy, breastfeeding, menopause, menopause age, and contraceptive methods were all involved. All characteristics were compared by chi-squared and nonparametric tests as applicable. Logistic regression model and sensitivity analysis were used to analyze the association between aICAS and MRH.

Results

A total of 1,052 female participants were involved in this study, of which 5.7% had moderate to severe aICAS. Tubal ligation was significantly associated with aICAS in univariate analysis [crude odds ratio (OR), 2.85; 95% CI, 1.22–6.62; P = 0.015]. This association was still significant among female participants over 60 years old after multivariate adjustment (adjusted OR, 4.36; 95% CI, 1.55–12.24; P = 0.005). Sensitivity analysis showed a similar result (adjusted OR, 3.76; 95% CI, 1.24–11.41; P = 0.020). Menopause lost significant association with aICAS after multivariate adjustment (adjusted OR, 1.68; 95% CI, 0.66–4.24; P = 0.275). No other MRH factors were found to be associated with aICAS.

Conclusion

Tubal ligation may be associated with a higher prevalence of aICAS in Chinese elderly women. This provides a new perspective to study the epidemiological characteristics of ICAS.

Genetic, Molecular, and Cellular Determinants of Sex-Specific Cardiovascular Traits

Despite the well-known sex dimorphism in cardiovascular disease traits, the exact genetic, molecular, and cellular underpinnings of these differences are not well understood. A growing body of evidence currently points at the links between cardiovascular disease traits and the genome, epigenome, transcriptome, and metabolome. However, the sex-specific differences in these links remain largely unstudied due to challenges in bioinformatic methods, inadequate statistical power, analytic costs, and paucity of valid experimental models. This review article provides an overview of the literature on sex differences in genetic architecture, heritability, epigenetic changes, transcriptomic signatures, and metabolomic profiles in relation to cardiovascular disease traits. We also review the literature on the associations between sex hormones and cardiovascular disease traits and discuss the potential mechanisms underlying these associations, focusing on human studies.

Circulating Exosomal miRNAs as Novel Biomarkers Perform Superior Diagnostic Efficiency Compared With Plasma miRNAs for Large-Artery Atherosclerosis Stroke

Recently, exosomal miRNAs have been reported to be associated with some diseases, and these miRNAs can be used for diagnosis and treatment. However, diagnostic biomarkers of exosomal miRNAs for ischemic stroke have rarely been studied. In the present study, we aimed to identify exosomal miRNAs that are associated with large-artery atherosclerosis (LAA) stroke, the most common subtype of ischemic stroke; to further verify their diagnostic efficiency; and to obtain promising biomarkers. High-throughput sequencing was performed on samples from 10 subjects. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed on exosomes and plasma in the discovery phase (66 subjects in total) and the validation phase (520 subjects in total). We identified 5 candidate differentially expressed miRNAs (miR-369-3p, miR-493-3p, miR-379-5p, miR-1296-5p, and miR-1277-5p) in the discovery phase according to their biological functions, 4 of which (miR-369-3p, miR-493-3p, miR-379-5p, and miR-1296-5p) were confirmed in the validation phase. These four exosomal miRNAs could be used to distinguish LAA samples from small artery occlusion (SAO) samples, LAA samples from atherosclerosis (AS) samples, and LAA samples from control samples and were superior to plasma miRNAs. In addition, composite biomarkers achieved higher area under the curve (AUC) values than single biomarkers. According to our analysis, the expression levels of exosomal miR-493-3p and miR-1296-5p were negatively correlated with the National Institutes of Health Stroke Scale (NIHSS) score. The four identified exosomal miRNAs are promising biomarkers for the diagnosis of LAA stroke, and their diagnostic efficiency is superior to that of their counterparts in plasma.

Importance of sex and gender in ischaemic stroke and carotid atherosclerotic disease

Stroke is a leading cause of death and disability worldwide. Women are disproportionately affected by stroke, exhibiting higher mortality and disability rates post-stroke than men. Clinical stroke research has historically included mostly men and studies were not properly designed to perform sex- and gender-based analyses, leading to under-appreciation of differences between men and women in stroke presentation, outcomes, and response to treatment. Reasons for these differences are likely multifactorial; some are due to gender-related factors (i.e. decreased social support, lack of stroke awareness), yet others result from biological differences between sexes. Unlike men, women often present with 'atypical' stroke symptoms. Lack of awareness of 'atypical' presentation has led to delays in hospital arrival, diagnosis, and treatment of women. Differences also extend to carotid atherosclerotic disease, a cause of stroke, where plaques isolated from women are undeniably different in morphology/composition compared to men. As a result, women may require different treatment than men, as evidenced by the fact that they derive less benefit from carotid revascularization than men but more benefit from medical management. Despite this, women are less likely than men to receive medical therapy for cardiovascular risk factor management. This review focuses on the importance of sex and gender in ischaemic stroke and carotid atherosclerotic disease, summarizing the current evidence with respect to (i) stroke incidence, mortality, awareness, and outcomes, (ii) carotid plaque prevalence, morphology and composition, and gene connectivity, (iii) the role of sex hormones and sex chromosomes in atherosclerosis and ischaemic stroke risk, and (iv) carotid disease management.

Menopause and cardiometabolic diseases: What we (don't) know and why it matters

This narrative review discusses the current understanding, knowledge gaps and challenges in expanding our knowledge of the association between menopause and the reproductive aging process and cardiometabolic disease (CMD) in women, with a focus on type 2 diabetes and cardiovascular disease. The physiological changes that occur at different stages of the reproductive life span, as well as type of menopause and timing, are factors widely associated with CMD risk; however, the underlying mechanisms remain either unclear or insufficiently studied. Decreased ovarian estrogen production and relative androgen excess around menopause onset are the most studied factors linking menopause and cardiometabolic health; nevertheless, the evidence is not persuasive and other hypotheses might explain the changes in CMD risk during menopausal transition. In this context, hormone therapy has been widely adopted in the treatment and prevention of CMD, although uncertainty regarding its cardiometabolic effects has raised the need to optimize therapeutic modalities. Mechanisms such as the "iron overload theory" and new "omics" platforms could provide new insights into potential pathways underlying the association between menopause and cardiometabolic health, such as the DNA damage response. Although it has been widely reported that environmental and lifestyle factors affect both menopause and cardiometabolic health, there is little evidence on the role of these exposures in menopause-associated CMD risk.

Expression of Resistin, Chemerin, and Chemerin's Receptor in the Unstable Carotid Atherosclerotic Plaque

[Figure: see text].

Association of Serum Testosterone and Luteinizing Hormone With Blood Pressure and Risk of Cardiovascular Disease in Middle-Aged and Elderly Men

Background

The age‐related decline in testosterone levels is thought to be of great importance for male aging and cardiovascular diseases. However, data are controversial on whether abnormal sex hormones are linked to the presence of cardiovascular diseases and it is also uncertain how blood pressure modifies the association between testosterone levels and major cardiovascular diseases.

Methods and Results

This is a multicenter, population‐based, cross‐sectional study of 6296 men conducted between 2013 and 2016. Basic information and clinical symptoms were obtained by questionnaires. Blood pressure and plasma levels of total testosterone, sex hormone–binding globulin, luteinizing hormone, and free testosterone were determined in men in a multistage random, cluster sampling in 6 provinces of China. There were 5786 Chinese men (mean [SD] age 55.0 [10.1] years) included after exclusion criteria were applied; 37.2% (2150) of them were diagnosed with hypertension. Total testosterone, free testosterone, and sex hormone–binding globulin were inversely associated with the prevalence of hypertension. Age >65 years or body mass index ≥24 negatively impacted the inverse correlation between testosterone levels and hypertension, whereas smoking and family history of hypertension strengthened the correlation. In participants with grade 2 hypertension, total testosterone was positively associated with the presence of stroke, and luteinizing hormone was also positively correlated with cardiovascular and cerebrovascular diseases.

Conclusions

Lower total testosterone could be a promising risk marker for prevalent hypertension. Both low and high levels of testosterone are associated with greater cardiovascular risk. Primary hypogonadism may be a risk marker for major cardiovascular diseases in men with severe hypertension.

Magnetic resonance imaging of carotid plaques: current status and clinical perspectives

Rupture of a vulnerable carotid plaque is one of the leading causes of stroke. Carotid magnetic resonance imaging (MRI) is able to visualize all the main hallmarks of plaque vulnerability. Various MRI sequences have been developed in the last two decades to quantify carotid plaque burden and composition. Often, a combination of multiple sequences is used. These MRI techniques have been extensively validated with histological analysis of carotid endarterectomy specimens. High agreement between the MRI and histological measures of plaque burden, intraplaque hemorrhage (IPH), lipid-rich necrotic core (LRNC), fibrous cap (FC) status, inflammation and neovascularization has been demonstrated. Novel MRI sequences allow to generate three-dimensional isotropic images with a large longitudinal coverage. Other new sequences can acquire multiple contrasts using a single sequence leading to a tremendous reduction in scan time. IPH can be easily identified as a hyperintense signal in the bulk of the plaque on strongly T₁-weighted images, such as magnetization-prepared rapid acquisition gradient echo images, acquired within a few minutes with a standard neurovascular coil. Carotid MRI can also be used to evaluate treatment effects. Several meta-analyses have demonstrated a strong predictive value of IPH, LRNC, thinning or rupture of the FC for ischemic cerebrovascular events. Recently, in a large meta-analysis based on individual patient data of asymptomatic and symptomatic individuals with carotid artery stenosis, it was shown that IPH on MRI is an independent risk predictor for stroke, stronger than any known clinical risk parameter. Expert recommendations on carotid plaque MRI protocols have recently been described in a white paper. The present review provides an overview of the current status and applications of carotid plaque MR imaging and its future potential in daily clinical practice.

A Timing Effect of 17-β Estradiol on Atherosclerotic Lesion Development in Female ApoE-/- Mice

Differences in size or composition of existing plaques at the initiation of estrogen (E2) therapy may underpin evidence of increased risk of atherosclerosis-associated clinical sequelae. We investigated whether E2 had divergent effects on actively-growing versus established-advanced atherosclerotic lesions. Eight weeks of subcutaneous bi-weekly injections of 3 µg/g 17β-estradiol (n = 18) or vehicle control (n = 22) were administered to female Apolipoprotein null-mice aged 25- or 45 weeks old. Histological assessment of lesion size within the brachiocephalic artery was conducted. Lesion composition was also assessed with acellular, calcification and fibrosis areas measured and other cellular features (intimal thickening, foam cells, lipid pools and cholesterol) scored (0–3) for severity. The comparison showed increased lesion size and calcified area with advancing age but no effect of E2. However, subtle changes in composition were observed following E2. Within the younger group, E2 increased intima thickening and acceleration of calcification. In the older group, E2 increased the thickness of the lesion cap. Therefore, this study shows different effects of E2 depending on the underlying stage of lesion development at the time of initiation of treatment. These divergent changes help explain the controversy of the adverse effects of E2 treatment in cardiovascular disease.

Objectives, design and main findings until 2020 from the Rotterdam Study

The Rotterdam Study is an ongoing prospective cohort study that started in 1990 in the city of Rotterdam, The Netherlands. The study aims to unravel etiology, preclinical course, natural history and potential targets for intervention for chronic diseases in mid-life and late-life. The study focuses on cardiovascular, endocrine, hepatic, neurological, ophthalmic, psychiatric, dermatological, otolaryngological, locomotor, and respiratory diseases. As of 2008, 14,926 subjects aged 45 years or over comprise the Rotterdam Study cohort. Since 2016, the cohort is being expanded by persons aged 40 years and over. The findings of the Rotterdam Study have been presented in over 1700 research articles and reports. This article provides an update on the rationale and design of the study. It also presents a summary of the major findings from the preceding 3 years and outlines developments for the coming period.

Associations of Endogenous Sex Hormones with Carotid Plaque Burden and Characteristics in Midlife Women

CONTEXT

Endogenous sex hormones may be involved in the pathogenesis of cardiovascular disease (CVD) in women. Carotid plaque characteristics, such as echogenicity, an ultrasound measure that reflects plaque composition, may identify unstable plaques that are more likely to rupture, precipitating a CVD event. However, few studies have considered sex steroids in relation to carotid plaque and its characteristics.

OBJECTIVE

To evaluate estrone (E1), estradiol (E2), testosterone (T), sex hormone binding globulin (SHBG), and free T (FT) in relation to carotid plaque in women.

DESIGN, SETTING, AND PARTICIPANTS

In MsHeart, a cross-sectional study of 304 women aged 40 to 60 years, participants underwent a carotid artery ultrasound assessment. The current analysis included MsHeart participants with carotid plaque (n = 141, 46%). E1, E2, and T were assayed using liquid chromatography-tandem mass spectrometry; FT was estimated using ensemble allostery models. Regression models were adjusted for sociodemographic characteristics and CVD risk factors.

MAIN OUTCOMES

Carotid plaque burden (number of plaques, total plaque area [TPA]) and characteristics (calcification, echogenicity) were determined using semi-automated software.

RESULTS

SHBG was inversely related to TPA (odds ratio [OR] 0.39; 95% confidence interval [CI] 0.21, 0.74; multivariable) and higher FTs were associated with greater TPA (OR 2.89; 95% CI 1.31, 6.37; multivariable). Higher E1 was related to echogenicity (OR 2.31; 95% CI 1.26, 4.33; multivariable), characteristic of more stable plaque.

CONCLUSIONS

SHBG and FT are related to TPA while E1 is related to plaque echogenicity, suggesting these hormones have different roles in the development of carotid plaque. Our findings highlight the importance of sex hormones in the development of carotid plaque in midlife women.

Plasma Estradiol and Testosterone Levels and Ischemic Stroke in Postmenopausal Women

Background and Purpose- Although exogenous hormone therapy (HT) use has been associated with increased risk of ischemic stroke in postmenopausal women, it remains unknown whether sex hormone levels contribute to ischemic stroke risk. We aimed to estimate associations between plasma sex hormone levels and ischemic stroke risk, by HT status, in a nested case-control study of postmenopausal women from the NHS (Nurses' Health Study). Methods- Women with confirmed incident ischemic stroke (n=419) were matched with controls (n=419) by age, HT use, and other factors. Plasma estradiol and testosterone levels were measured using liquid chromatography tandem mass spectrometry; SHBG (sex hormone-binding globulin) was assayed by electrochemiluminescence immunoassay. Associations of total and free estradiol and testosterone, the estradiol/testosterone ratio, and SHBG with ischemic stroke were estimated using conditional logistic regressions stratified by HT status with adjustment for matching and cardiovascular risk factors. Results- Current HT users had different hormone profiles from never/past users. No clear linear trends were observed between estradiol (total or free) levels or the estradiol/testosterone ratio and ischemic stroke risk among either current users (P_trend>0.1) or never/past users (P_trend>0.6). For both current and never/past users, the associations between some of the sex hormones and ischemic stroke differed by body mass index categories (P_interaction≤0.04). For women with a body mass index <25 kg/m², a higher estradiol/testosterone ratio was associated with significantly elevated ischemic stroke risk among current users (P_trend=0.01), and higher levels of total and free estradiol were significantly associated with higher ischemic stroke risk among never/past users (P_trend≤0.04). Testosterone and SHBG were not associated with ischemic stroke in either current or never/past users. Conclusions- Our findings do not support a role of sex hormone levels in mediating ischemic stroke risk among postmenopausal women. Replications in additional larger studies are required.

The Association of Serum Testosterone Levels With Recurrence and Mortality After Acute Ischemic Stroke in Males

The current study aimed to investigate whether low testosterone predicted the recurrence and clinical outcomes after acute ischemic stroke (AIS) in males. From June 2015 through August 2017, the study prospectively enrolled 110 male AIS patients. All received detailed evaluations at admission and were followed for at least 1 year. The cumulative incidence, overall survival, length of hospital stay, and the percentage of previous stroke were compared between subjects with testosterone <440 ng/dl and >440 ng/dl. The median age was 62 years (range, 35–93 years). The median serum testosterone at admission was 438 [203] ng/dl (range, 44–816 ng/dl); 55 patients (50%) had testosterone <440 ng/dl and were considered as low testosterone. The median follow-up was 23 months. During the period, 12 recurrences and 10 deaths occurred. The 1-year and 3-year cumulative recurrence rate were 8.3% and 11.9%, respectively; the 1-year and 3-year overall survival were 96.3% and 84.6%, respectively. The cumulative recurrence rates were similar between the two testosterone groups (log-rank test, p = .88). Low testosterone was associated with poor survival with marginal significance (log-rank test, p = .079). Men with low testosterone had a higher percentage of previous stroke (29.1% versus 12.7%, p = .035). The mean lengths of hospital stay were similar between the two testosterone groups (16.6 ± 15.8 days versus 14.0 ± 10.6, p = .31). Total testosterone at admission fails to predict stroke recurrence. However, men with low testosterone at admission are more likely to have previous stroke and may have a higher all-cause mortality rate after AIS.

Estrogen-mediated protection against coronary heart disease: The role of the Notch pathway

Estrogen regulates a plethora of biological processes, under physiological and pathological conditions, by affecting key pathways involved in the regulation of cell proliferation, fate, survival and metabolism. The Notch receptors are mediators of communication between adjacent cells and are key determinants of cell fate during development and in postnatal life. Crosstalk between estrogen and the Notch pathway intervenes in many processes underlying the development and maintenance of the cardiovascular system. The identification of molecular mechanisms underlying the interaction between these types of endocrine and juxtacrine signaling are leading to a deeper understanding of physiological conditions regulated by these steroid hormones and, potentially, to novel therapeutic approaches to prevent pathologies linked to reduced levels of estrogen, such as coronary heart disease, and cardiotoxicity caused by hormone therapy for estrogen-receptor-positive breast cancer.

Analysis of serum changes in response to a high fat high cholesterol diet challenge reveals metabolic biomarkers of atherosclerosis

Atherosclerotic plaques are characterized by an accumulation of macrophages, lipids, smooth muscle cells, and fibroblasts, and, in advanced stages, necrotic debris within the arterial walls. Dietary habits such as high fat and high cholesterol (HFHC) consumption are known risk factors for atherosclerosis. However, the key metabolic contributors to diet-induced atherosclerosis are far from established. Herein, we investigate the role of a 2-year HFHC diet challenge in the metabolic changes of development and progression of atherosclerosis. We used a non-human primate (NHP) model (baboons, n = 60) fed a HFHC diet for two years and compared metabolomic profiles in serum from animals on baseline chow with serum collected after the challenge diet using two-dimensional gas chromatography time-of-flight mass-spectrometry (2D GC-ToF-MS) for untargeted metabolomic analysis, to quantify metabolites that contribute to atherosclerotic lesion formation. Further, clinical biomarkers associated with atherosclerosis, lipoprotein measures, fat indices, and arterial plaque formation (lesions) were quantified. Using two chemical derivatization (i.e., silylation) approaches, we quantified 321 metabolites belonging to 66 different metabolic pathways, which revealed significantly different metabolic profiles of HFHC diet and chow diet fed baboon sera. We found heritability of two important metabolites, lactic acid and asparagine, in the context of diet-induced metabolic changes. In addition, abundance of cholesterol, lactic acid, and asparagine were sex-dependent. Finally, 35 metabolites correlated (R2, 0.068-0.271, P < 0.05) with total lesion burden assessed in three arteries (aortic arch, common iliac artery, and descending aorta) which could serve as potential biomarkers pending further validation. This study demonstrates the feasibility of detecting sex-specific and heritable metabolites in NHPs with diet-induced atherosclerosis using untargeted metabolomics allowing understanding of atherosclerotic disease progression in humans.

Proteomics and multivariate modelling reveal sex-specific alterations in distinct regions of human carotid atheroma

Background

Atherosclerotic lesions are comprised of distinct regions with different proteomic profiles. Men and women develop differences in lesion phenotype, with lesions from women generally being more stable and less prone to rupture. We aimed to investigate the differences in proteomic profiles between sexes, including distinct lesion regions, to identify altered proteins that contribute to these differences observed clinically.

Methods

Carotid endarterectomy samples (ten men/ten women) were obtained, and intraplaque biopsies from three distinct regions (internal control, fatty streak and plaque) were analysed by tandem-mass spectrometry. Multivariate statistical modelling, using orthogonal partial least square-discriminant analysis, was used to discriminate the proteomes between men and women.

Results

Multivariate discriminant modelling revealed proteins from 16 functional groups that displayed sex-specific associations. Additional statistics revealed ten proteins that display region-specific alterations when comparing sexes, including proteins related to inflammatory response, response to reactive oxygen species, complement activation, transport and blood coagulation. Transport protein afamin and blood coagulation proteins antithrombin-III and coagulation factor XII were significantly increased in plaque region from women. Inflammatory response proteins lysozyme C and phospholipase A2 membrane-associated were significantly increased in plaque region from men. Limitations with this study are the small sample size, limited patient information and lack of complementary histology to control for cell type differences between sexes.

Conclusions

This pilot study, for the first time, utilises a multivariate proteomic approach to investigate sexual dimorphism in human atherosclerotic tissue, and provides an essential proteomic platform for further investigations to help understand sexual dimorphism and plaque vulnerability in atherosclerosis.

Electronic supplementary material

The online version of this article (10.1186/s13293-018-0217-3) contains supplementary material, which is available to authorized users.

Sex differences in metabolism and cardiometabolic disorders

PURPOSE OF REVIEW

Sex differences are pervasive in metabolic and cardiovascular traits, yet they have often been ignored in human and animal model research. Sex differences can arise from reversible hormonal effects, from irreversible organizational (developmental) processes, and from gene expression differences from the X and Y chromosomes. We briefly review our current understanding of the impact of these factors in metabolic traits and disorders, with an emphasis on the recent literature.

RECENT FINDINGS

Novel sex differences continue to be identified for metabolic and cardiovascular traits. For example, it is now clear that gut microbiota tend to differ between men and women, with potentially large implications for disease susceptibility. Also, tissue-specific gene regulation differs between men and women, contributing to differential metabolism. These new insights will open up personalized therapeutic avenues for cardiometabolic diseases.

SUMMARY

Sex differences in body fat distribution, glucose homeostasis, insulin signaling, ectopic fat accumulation, and lipid metabolism during normal growth and in response to hormonal or nutritional imbalance are mediated partly through sex hormones and the sex chromosome complement. Most of these differences are mediated in a tissue-specific manner. Important future goals are to better understand the interactions between genetic variation and sex differences, and to bring an understanding of sex differences into clinical practice.

Coronary artery disease in post-menopausal women: are there appropriate means of assessment?

The recognition of sex differences in cardiovascular disease, particularly the manifestations of coronary artery disease (CAD) in post-menopausal women, has introduced new challenges in not only understanding disease mechanisms but also identifying appropriate clinical means of assessing the efficacy of management strategies. For example, the majority of treatment algorithms for CAD are derived from the study of males, focus on epicardial stenoses, and inadequately account for the small intramyocardial vessel disease in women. However, newer investigational modalities, including stress perfusion cardiac magnetic resonance imaging and positron emission tomography are providing enhanced diagnostic accuracy and prognostication for women with microvascular disease. Moreover, these investigations may soon be complemented by simpler screening tools such as retinal vasculature imaging, as well as novel biomarkers (e.g. heat shock protein 27). Hence, it is vital that robust, sex-specific cardiovascular imaging modalities and biomarkers continue to be developed and are incorporated into practice guidelines that are used to manage women with CAD, as well as gauge the efficacy of any new treatment modalities. This review provides an overview of some of the sex differences in CAD and highlights emerging advances in the investigation of CAD in post-menopausal women.