Relative androgen excess and increased cardiovascular risk after menopause: a hypothesized relation

Longitudinal Changes in Sex Hormone Binding Globulin (SHBG) and Risk of Incident Diabetes: The Study of Women's Health Across the Nation (SWAN)

OBJECTIVE

To investigate the associations of longitudinal changes in sex hormone binding globulin (SHBG) and testosterone (T) over the menopause transition with the risk of diabetes.

RESEARCH DESIGN AND METHODS

We followed 2,952 participants in the Study of Women's Health Across the Nation (SWAN) who were premenopausal or early perimenopausal and diabetes-free at baseline. SHBG,T, and estradiol (E2) levels were measured at up to 13 follow-up visits (over up to 17 years). We used complementary log-log-based discrete-time survival models anchored at baseline.

RESULTS

Diabetes developed in 376 women. A 5-unit increase in time-varying SHBG was associated with a 10% reduced risk of diabetes (hazard ratio [HR] 0.91, 95% CI 0.87-0.95), adjusting for covariates, and baseline SHBG,T, and E2 levels. Time-varying T was not associated with diabetes risk. Compared with the lowest quartile for annual rate of change of SHBG since baseline (quartile 1 [Q1] -92.3 to -1.5 nmol/L), all other quartiles were associated with a decreased risk of diabetes adjusting for covariates and baseline SHBG; associations persisted after adjusting for rate of change of T and E2 (Q2 [> -1.5 to -0.2 nmol/L] HR 0.33, 95% CI 0.23-0.48; Q3 [> -0.2 to 1.3 nmol/L] HR 0.37, 95% CI 0.25-0.55; Q4 [>1.3 to 82.0 nmol/L] HR 0.43, 95% CI 0.30-0.63).

CONCLUSIONS

Increasing levels of SHBG over the menopause transition were associated with a decreased risk of incident diabetes. Stable to increasing rates of change in SHBG were also independently associated with a decreased risk of diabetes compared with decreasing rates of change, suggesting SHBG may affect glucose through a mechanism beyond androgenicity.

Age at natural menopause and development of chronic diseases in the female population of Kharameh, Iran: A historical cohort study

Background and Aims

Declines in estradiol levels after menopause have been reported to be associated with several health outcomes. This study aimed to determine the effect of age at natural menopause (ANM) on some of the most common chronic diseases.

Methods

This historical cohort study was performed on 2636 postmenopausal women aged 40-70 years participating in phase one of the PERSIAN cohort study in Kharameh, Iran, during 2015-2017. The effect of early (<45 years), intermediate (45-53 years), and late menopause (>53 years) on chronic diseases such as hypertension, diabetes, ischemic heart diseases, stroke, thyroid diseases, and depression was assessed using classic logistic regression for diseases with an incidence rate of more than 10% and Firth's logistic regression for diseases with an incidence of less than this amount.

Results

The mean age of women was 53.48 ± 8.59. Respectively, early and intermediate menopause was associated with ischemic heart disease (odds ratio [OR = 1.61, 95% confidence interval [CI]: 1.08-2.42; p = 0.020), (OR = 1.57, 95% CI: 1.13-2.21; p = 0.008) and thyroid diseases (OR = 3.10, 95% CI: 1.64-6.24; p < 0.001), (OR = 1.83, 95% CI: 1.02-3.57; p = 0.042). furthermore, early menopause was a risk factor for diabetes (OR = 1.46, 95% CI: 1.07-2.00; p = 0.018), depression (OR = 4.79, 95% CI: 2.20-11.79; p = <0.001) and stroke (OR = 3.00, 95% CI: 1.08-9.32; p = 0.034).

Conclusions

In this study, women with diabetes, ischemic heart diseases, stroke, thyroid disorders, and depression had a younger ANM compared to their healthy counterparts. Therefore, applying appropriate strategies to postpone the age of menopause, can reduce the incidence of these types of chronic diseases.

Association between bone mineral density and coronary plaque burden in patients with coronary artery disease: a cross-sectional study using quantitative computed tomography

PURPOSE

To evaluate the association between osteoporosis and coronary calcification and coronary plaque burden in patients with atherosclerosis and coronary artery disease (CAD).

METHODS

This study included 290 men and 177 postmenopausal women with angiography-confirmed atherosclerosis or CAD who underwent chest multidetector row computed tomography covering L1-L2 between September 2020 and October 2021. Quantitative computed tomography was used to measure the lumbar vertebra's bone mineral density (BMD). The coronary artery calcium score (CACS) and total coronary plaque burden were quantified using the Agatston and modified Gensini scores, respectively. Associations between BMD and CACS and modified Gensini scores were assessed using multivariate regression analysis. Lasso regression was used in model selection.

RESULTS

In men, BMD was inversely associated with CACS [ β  = -0.24; 95% confidence interval (CI), -0.35 to -0.13; P  < 0.001) and coronary artery calcification (CAC) presence [odds ratio (OR) = 0.71; 95% CI, 0.52-0.96; P  = 0.03) in the unadjusted model. After adjusting for age, modified Gensini score, prior percutaneous coronary intervention and hypertension, BMD was inversely associated with CACS ( β  = -0.11; 95% CI, -0.22 to -0.01; P  = 0.04). In postmenopausal women, BMD was inversely associated with CACS ( β  = -0.24; 95% CI, -0.39 to 0.10; P  < 0.001) and CAC presence (OR = 0.66; 95% CI, 0.47-0.92; P  = 0.01) in the unadjusted model but no other models ( P  > 0.05). In both sexes, BMD did not correlate with the modified Gensini score or CAD prevalence (all P  > 0.05).

CONCLUSION

In patients with coronary atherosclerosis and CAD, BMD of the lumbar vertebra correlated inversely with CACS in men but not postmenopausal women. Additionally, BMD did not correlate with the modified Gensini score in both sexes.

The association of menopause with cardiometabolic disease risk factors in low- and middle-income countries: a systematic review and meta-analyses

IMPORTANCE

Menopause is an integral part of women's health, and studies in high-income countries have shown an increase in cardiometabolic disease (CMD) risk factors in postmenopausal compared with premenopausal women. However, to date, no study has combined and assessed such studies across low- and middle-income countries. This would better inform early monitoring and intervention strategies for reducing CMD risk factor levels in midlife women in these regions.

OBJECTIVE

This study aimed to evaluate evidence from the literature on differences in CMD risk factors between premenopausal and postmenopausal midlife women living in low- and middle-income countries.

EVIDENCE REVIEW

A systematic review with meta-analysis of original articles of all study designs from the databases PubMed, PubMed Central, Scopus, and ISI Web of Science was conducted from conception until April 24, 2023. Studies that met the inclusion criteria were included in the analysis. Quality assessment of the articles was done using the Newcastle-Ottawa Scale, adapted for each study design. The study protocol was registered with the International Prospective Register of Systematic Reviews and adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. For the meta-analysis, fixed-effects models were used to pool the odds ratios (OR), as measures of association.

FINDINGS

Our search identified 4,849 relevant articles: 44 for the systematic review and 16 for the meta-analysis, in accordance with our inclusion criteria. Compared with premenopausal women, the postmenopausal stage was associated with metabolic syndrome (OR, 1.18 [95% CI, 1.11-1.27]), high waist-to-hip ratio (OR, 1.22 [95% CI, 1.12-1.32]), hypertension (OR, 1.10 [95% CI, 1.04-1.16]), elevated triglycerides (OR, 1.16 [95% CI, 1.11-1.21]), and elevated plasma glucose (OR, 1.21 [95% CI, 1.15-1.28]).

CONCLUSIONS AND RELEVANCE

This study confirmed that CMD risk factors are present at higher levels in postmenopausal than premenopausal women. This demonstrates an urgent need for public health policies that focus on early monitoring and interventions targeted at reducing CMD risk and related adverse outcomes in midlife women in these nations.

Estrogen-mediated mechanisms in hypertension and other cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of death globally for men and women. Premenopausal women have a lower incidence of hypertension and other cardiovascular events than men of the same age, but diminished sex differences after menopause implicates 17-beta-estradiol (E2) as a protective agent. The cardioprotective effects of E2 are mediated by nuclear estrogen receptors (ERα and ERβ) and a G protein-coupled estrogen receptor (GPER). This review summarizes both established as well as emerging estrogen-mediated mechanisms that underlie sex differences in the vasculature during hypertension and CVD. In addition, remaining knowledge gaps inherent in the association of sex differences and E2 are identified, which may guide future clinical trials and experimental studies in this field.

The Impact of Menopause on Cardiovascular Aging: A Comprehensive Review of Androgen Influences

Menopause represents a critical life stage in women, characterized by hormonal changes that significantly impact cardiovascular health. While the decline in estrogen levels has long been recognized as a major contributor to cardiovascular aging in menopausal women, the role of androgens, particularly testosterone, has gained increasing attention in recent years. This comprehensive review aims to provide a thorough understanding of the impact of menopause on cardiovascular aging, with a specific focus on the influences of androgens. A literature search was conducted to gather relevant studies and clinical evidence exploring the relationship between menopause, androgens, and cardiovascular health. The review integrates findings from various studies to present a holistic view of the topic. The review outlines the changes in hormone levels during menopause and discusses the cardiovascular risk factors associated with this transition. Furthermore, it explores the impact of menopause on cardiovascular structure and function, elucidating the underlying mechanisms that contribute to cardiovascular aging. Androgens' significance in maintaining cardiovascular homeostasis is discussed, followed by exploring the effects of androgen decline during menopause on lipid profiles, insulin sensitivity, vascular function, and other cardiovascular parameters. The review delves into the mechanisms of androgen action on the cardiovascular system, emphasizing the role of androgen receptors and the intricate interplay between androgens, estrogens, and other hormones. Clinical evidence supporting the effects of androgens on cardiovascular aging is presented, including studies investigating the association between androgen levels and cardiovascular outcomes. Additionally, the impact of androgen replacement therapy (ART) on cardiovascular risk markers and events in menopausal women is examined, along with controversies and conflicting findings surrounding the use of androgen therapy in cardiovascular aging. This structured review provides a comprehensive understanding of the impact of menopause on cardiovascular aging, with a specific focus on the role of androgens. By highlighting the significance of androgens in cardiovascular health during menopause, this review aims to create an initial impression and interest among readers, inviting potential citations in the future. The findings underscore the need for further research and offer insights into managing cardiovascular aging in menopausal women, including lifestyle interventions, pharmacological approaches, and the potential role of personalized medicine and precision therapies.

The causal effect of bioavailable testosterone on primary biliary cholangitis in female patients: A Bidirectional Mendelian randomization analysis

BACKGROUND

Primary biliary cholangitis (PBC) primarily affects female in their 4th to 6th decade of life at which stage female's sex hormones change dramatically. Sex hormones have a wide range of effects on the liver and immune system. However, it remains unclear whether sex hormonal changes mediate the onset of PBC.

AIMS

This study investigated the causal effect between total testosterone (TT), bioavailable testosterone (BAT), sex hormone binding globulin (SHBG) in female and PBC using public GWAS summary data.

METHODS

Data on TT, BAT, SHBG in female were obtained from a previous study based on the UK Biobank. PBC GWAS summary data was obtained from a genome-wide meta-analysis. We used several methods to make the conclusion robust. Various sensitivity analyses had been conducted to assess the consistency of our findings.

RESULTS

Our Mendelian randomization analysis revealed that the genetically predicted BAT in female was positively associated with PBC and SHBG in female was negatively associated with PBC. The results obtained from different methods are similar, which proves the reliability of the results.

CONCLUSIONS

Our study supported a causal relationship of BAT and SHBG in female on PBC. To confirm the association between testosterone and PBC, more research should be conducted.

Low endogenous estradiol levels are associated with elevated risk of cardiovascular disease mortality in young and middle-aged men in the United States

BACKGROUND AND AIMS

Evidence for the association of total estradiol (E2) with cardiovascular disease (CVD) in young men is limited. We investigated the association of total E2 or free estradiol (FE2) and CVD mortality in a nationally representative multiracial sample of young and middle-aged men in the United States.

METHODS

Data were from 954 men without CVD, cancer, diabetes and not on androgen therapy or taking anabolic steroids, who participated in the National Health and Nutrition Examination Survey (1988-1991), for whom E2 was measured, and were followed for mortality through to 2015. Fasting serum levels of E2 were measured using competitive electrochemiluminescence immunoassays. Free estradiol was estimated from the levels of estradiol, sex hormone binding globulin, and albumin. International Classification of Diseases codes were used to define CVD mortality. Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

The average age of participants at baseline was 35.7 ± 11.6 years, with 11% and 6% reporting Black and Hispanic race and ethnicity, respectively. During a median follow-up of 25.2 years, 40 CVD deaths were recorded. Controlling for baseline demographic and CVD risk factors, and total testosterone levels, a 1 standard deviation decrement in log E2 (HR: 2.33, 95%CI: 1.11-5.00) or FE2 (HR: 1.89, 95%CI: 1.01-3.57) was associated with elevated risk of CVD mortality. This elevated risk was largely limited to non-Hispanic White men.

CONCLUSIONS

In this study, low levels of E2 or FE2 were associated with elevated risk of CVD mortality.

Associations between endogenous sex hormone levels and adipokine levels in the Multi-Ethnic Study of Atherosclerosis

Background

Differences in sex hormone levels contribute to differences in cardiovascular disease (CVD) risk. Adipokines play a role in cardiometabolic pathways and have differing associations with CVD. Adipokine levels differ by sex; however, the association between sex hormone profiles and adipokines is not well established. We hypothesized that a more androgenic sex hormone profile would be associated with higher leptin and resistin and lower adiponectin levels among postmenopausal women, with the opposite associations in men.

Methods

We performed an analysis of 1,811 adults in the Multi-Ethnic Study of Atherosclerosis who had both sex hormones and adipokines measured an average of 2.6 years apart. Sex hormones [Testosterone (T), estradiol (E2), sex hormone binding globulin (SHBG), and dehydroepiandrosterone (DHEA)] were measured at exam 1; free T was estimated. Serum adipokines (leptin, resistin, adiponectin) were measured at exams 2 or 3. We used multivariable linear regression to examine the cross-sectional associations between sex hormones and adipokines.

Results

The mean (SD) age was 63 (10) years, 48% were women; 59% non-White participants. For leptin, after adjusting for demographics only, higher free T and lower SHBG, were associated with higher leptin in women; this association was attenuated after further covariate adjustment. However in men, higher free T and lower SHBG were associated with greater leptin levels in fully adjusted models. For adiponectin, lower free T and higher SHBG were associated with greater adiponectin in both women and men after adjustment for CVD risk factors. For resistin, no significant association was found women, but an inverse association with total T and bioT was seen in men.

Conclusion

Overall, these results further suggest a more androgenic sex profile (higher free T and lower SHBG) is associated with a less favorable adipokine pattern. These findings may provide mechanistic insight into the interplay between sex hormones, adipokines, and CVD risk.

Oxidative and Cellular Stress Markers in Postmenopause Women with Diabetes: The Impact of Years of Menopause

Women live approximately one-third of their lives in postmenopause. Among postmenopausal women, type 2 diabetes mellitus (DM2) is one of the most prevalent chronic diseases. These conditions promote alterations in the oxidative, metabolic, and immune-inflammatory profiles marked by higher extracellular 72 kDa-heat shock protein (eHSP72). Here, we investigated whether the time of menopause is associated with oxidative cellular stress marker levels in postmenopausal women with DM2. Sixty-four women were recruited (56.7 ± 12.6 years old) in the pre- (n = 22) and postmenopause (n = 42) period, with (n = 19) or without DM2 (n = 45), and a fasting blood collection was made for the evaluation of metabolic, oxidative, and inflammatory markers. We found that menopause and DM2 influenced metabolic and oxidative parameters and presented synergistic effects on the plasma lipoperoxidation levels. Also, postmenopausal women had the highest eHSP72 concentration levels associated with the years in postmenopause. We conclude that the time of menopause impacts the markers of cellular stress and increases the risk of oxidative stress, mainly when it is associated with DM2.

Association of serum androgens and coronary artery calcium scores in women

OBJECTIVE

To determine the association between serum androgens measured by high-resolution liquid chromatography-mass spectrometry and coronary artery calcium (CAC) scores.

DESIGN

Cross-sectional study.

SETTING

Academic institution.

PATIENT(S)

A total of 239 women, aged 40-75 years, with CAC testing and complete cardiovascular disease risk evaluation. Total T, DHEA, and androstenedione were measured using high-resolution liquid chromatography-mass spectrometry, whereas E₂ and sex hormone-binding globulin were measured using commercial assays.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Independent associations between CAC scores and sex steroids.

RESULT(S)

Overall, 164 subjects had a CAC score < 10, 48 had a CAC score between 10 and 100, and 27 had a score > 100. There were no differences in sex hormone levels between women with CAC scores > 10 vs. CAC scores ≤ 10. In multivariable models adjusting for age, body mass index, and low-density lipoprotein cholesterol, a higher T/E₂ ratio was associated with an elevated CAC score, with an unadjusted odds ratio associated with 1-SD change in log-transformed T/E₂ of 1.38 (95% confidence interval 1.01-1.89) and adjusted OR 1.02 (95% confidence interval 1.002-1.04). Total T, DHEA, androstenedione, sex hormone-binding globulin, and E₂ levels were not associated with increased CAC.

CONCLUSION(S)

In the general population, there are mixed reports regarding the relationship between serum androgens and risk factors for cardiovascular disease, and limited information on the relationship between androgens and subclinical atherosclerosis. Our study shows that increased androgens relative to estrogens may have a weak but independent association with subclinical atherosclerosis, as measured by CAC scores.

Sex difference: an important issue to consider in epidemiological and clinical studies dealing with serum paraoxonase-1

The aim of this study was to evaluate the influence of sex on serum paraoxonase-1 (PON1) activities and on its relationship with cardiovascular disease risk factors such as overall and central obesity. Arylesterase and lactonase activities of PON1 were assessed in 374 women and 92 men. Both arylesterase and lactonase activities were significantly higher in women compared to men (p<0.001), irrespectively of confounders such as high density lipoprotein-cholesterol, age, smoking and body mass index or waist circumference. Sex also strongly influenced the interplay between PON1 and both fat measures, with only the arylesterase showing a significant and independent inverse correlation with the former parameter (r = -0.248, p<0.001) and the risk of overall obesity (odds ratio: 0.559, 95% confidence interval: 0.340-0.919) in women, but not in men; conversely, neither of the two activities remained associated with waist circumference in men or women after full adjustment. Noteworthy, the association between arylesterase and BMI in the female subsample was significant among women younger than forty-five years (r = -0.453, p<0.001, R ² = 0.207). In conclusion, our study suggests that sex might chiefly influence PON1 activity and its contribution to cardiovascular disease risk. Further studies are needed to confirm and clarify our preliminary findings.

Sex hormones and stroke: Beyond estrogens

Stroke risk and poor stroke outcomes in postmenopausal women have usually beeen attributed to decreased levels of estrogen. However, two lines of evidence suggest that this hormone may not be solely responsible for elevated stroke risk in this population. First, the increased risk for CVD and stroke occurs much earlier than menopause at a time when estrogen levels are not yet reduced. Second, estrogen therapy has not successfully reduced stroke risk in all studies. Other sex hormones may therefore also contribute to stroke risk. Prior to menopause, levels of the gonadotrophin Follicle Stimulating Hormone (FSH) are elevated while levels of the gonadal peptide inhibin are lowered, indicating an overall decrease in ovarian reserve. Similarly, reduced estrogen levels at menopause significantly increase the ratio of androgens to estrogens. In view of the evidence that androgens may be unfavorable for CVD and stroke, this elevated ratio of testosterone to estrogen may also contribute to the postmenopause-associated stroke risk. This review synthesizes evidence from different clinical populations including natural menopause, surgical menopause, women on chemotherapy, and preclinical stroke models to dissect the role of ovarian hormones and stroke risk and outcomes.

Sex difference: an important issue to consider in epidemiological and clinical studies dealing with serum paraoxonase-1

The aim of this study was to evaluate the influence of sex on serum paraoxonase-1 (PON1) activities and on its relationship with cardiovascular disease risk factors such as overall and central obesity. Arylesterase and lactonase activities of PON1 were assessed in 374 women and 92 men. Both arylesterase and lactonase activities were significantly higher in women compared to men (p<0.001), irrespectively of confounders such as high density lipoprotein-cholesterol, age, smoking and body mass index or waist circumference. Sex also strongly influenced the interplay between PON1 and both fat measures, with only the arylesterase showing a significant and independent inverse correlation with the former parameter (r = −0.248, p<0.001) and the risk of overall obesity (odds ratio: 0.559, 95% confidence interval: 0.340–0.919) in women, but not in men; conversely, neither of the two activities remained associated with waist circumference in men or women after full adjustment. Noteworthy, the association between arylesterase and BMI in the female subsample was significant among women younger than forty-five years (r = −0.453, p<0.001, R² = 0.207). In conclusion, our study suggests that sex might chiefly influence PON1 activity and its contribution to cardiovascular disease risk. Further studies are needed to confirm and clarify our preliminary findings.

Sex-related differences in oxidative stress and neurodegeneration

Oxidative stress has been implicated in a number of neurodegenerative diseases spanning various fields of research. Reactive oxygen species can be beneficial or harmful, depending on their concentration. High levels of reactive oxygen species can lead to oxidative stress, which is an imbalance between free radicals and antioxidants. Increased oxidative stress can result in cell loss. Interestingly, sex differences have been observed in oxidative stress generation, which may underlie sex differences observed in neurodegenerative disorders. An enhanced knowledge of the role of sex hormones on oxidative stress signaling and cell loss can yield valuable information, leading to sex-based mechanistic approaches to neurodegeneration.

Gender-Related Differences and Short-Term Outcome of Stroke: Results from a Hospital-Based Registry in Sub-Saharan Africa

BACKGROUND

Studies suggest that sex differences have an impact on patients with stroke, but existing data in Africa remain inconclusive about this inference.

OBJECTIVES

To study sex differences in terms of the clinical profile and short-term outcome of stroke in the Douala General Hospital, Cameroon.

METHODS

A hospital-based prospective cohort study was carried out in a tertiary care hospital over an 8-year period, which included all patients admitted for confirmed acute stroke. Information about the history of stroke with emphasis on clinical profile and outcome was collected. Descriptive statistics, t test, and chi square test were used for comparisons, while the Kaplan-Meier curve was used for survival rate analysis.

RESULTS

Of the 818 patients included, 455 (55.6%) were male patients. When compared to males, female patients are more likely to experience a stroke at an older age (mean age 62.3 ± 14.1 vs. 58.4 ± 12.9 years, p < 0.001), to be unmarried, to remain unemployed, and to have higher rates of cardio-embolic stroke (p = 0.049), body mass index (p = 0.031), altered levels of consciousness at presentation (p = 0.005), higher mean HDL cholesterol levels (p = 0.001), and in-hospital complications (p = 0.011), especially urinary tract infections (p = 0.018). Males were more likely to have health insurance, to smoke, to consume alcohol (p < 0.001), and to have higher rates of dysarthria (p = 0.004), higher mean uric acid (p = 0.013), and creatinine (p < 0.001) concentrations. Ischemic and hemorrhagic strokes were more prevalent in men (p = 0.003). There are no sex differences in terms of stroke severity, length-of-hospital stay, case fatality, and functional outcome on admission.

CONCLUSIONS

Sex differences exist in the clinical profile of stroke but not in the outcome. Knowledge of these differences could help influence stroke prevention, thereby improving stroke burden in Africa.

Presence of Androgen Receptor Variant in Neuronal Lipid Rafts

Fast, nongenomic androgen actions have been described in various cell types, including neurons. However, the receptor mediating this cell membrane–initiated rapid signaling remains unknown. This study found a putative androgen receptor splice variant in a dopaminergic N27 cell line and in several brain regions (substantia nigra pars compacta, entorhinal cortex, and hippocampus) from gonadally intact and gonadectomized (young and middle-aged) male rats. This putative splice variant protein has a molecular weight of 45 kDa and lacks an N-terminal domain, indicating it is homologous to the human AR45 splice variant. Interestingly, AR45 was highly expressed in all brain regions examined. In dopaminergic neurons, AR45 is localized to plasma membrane lipid rafts, a microdomain involved in cellular signaling. Further, AR45 protein interacts with membrane-associated G proteins Gαq and Gαo. Neither age nor hormone levels altered AR45 expression in dopaminergic neurons. These results provide the first evidence of AR45 protein expression in the brain, specifically plasma membrane lipid rafts. AR45 presence in lipid rafts indicates that it may function as a membrane androgen receptor to mediate fast, nongenomic androgen actions.

The effects of oestrogens and their receptors on cardiometabolic health

Cardiovascular disease (CVD) is one of the leading causes of mortality in developed countries. The incidence of CVD is sexually dimorphic, and research has focused on the contribution of sex steroids to the development and progression of the cardiometabolic syndrome, which is defined as a clustering of interrelated risk factors that promote the development of atherosclerosis (which can lead to CVD) and type 2 diabetes mellitus. Data are inconclusive as to how sex steroids and their respective receptors increase or suppress the risk of developing the cardiometabolic syndrome and thus CVD. In this Review, we discuss the potential role, or roles, of sex hormones in cardiometabolic health by first focusing on the influence of oestrogens and their receptors on the risk of developing cardiometabolic syndrome and CVD. We also highlight what is known about testosterone and its potential role in protecting against the development of the cardiometabolic syndrome and CVD. Given the inconclusive nature of the data regarding the direct effects of each sex hormone, we advocate and highlight the importance of studying the relative levels and the ratio of sex hormones to each other, as well as the use of cross sex hormone therapy and its effect on cardiometabolic health.

Effect of Menstrual Cycle Phases on Plasma Lipid and Lipoprotein Levels in Regularly Menstruating Women

INTRODUCTION

Physiological cyclic variability in levels of sex hormones during a menstrual cycle may possibly have an impact on lipids, lipoprotein levels and therefore on cardiovascular health status of females.

AIM

To ascertain the effect of menstrual cycle phases on the levels of cardiovascular risk predictors i.e., plasma lipids and lipoproteins in healthy menstruating women.

MATERIALS AND METHODS

In the present study, 111 healthy regularly menstruating females aged 15-45 years were examined at two points of a menstrual cycle i.e., in the follicular phase (10th day) and in the luteal phase (22nd day) to find out the plasma levels of lipids and lipoproteins. The data were statistically analysed using paired t-test.

RESULTS

A significant decrease in the mean levels of Total Cholesterol (TC) (p=0.006), Low Density Lipoprotein Cholesterol (LDL-C) (p=0.004), TC/High Density Lipoprotein Cholesterol (HDL-C) (p=0.006), Low Density Lipoprotein Cholesterol (LDL)/HDL (p=0.01), and Triglyceride (TG)/HDL (p=0.02) was observed in the luteal phase compared to the follicular phase while TG (p=0.18), HDL-C (p=0.16). VLDL-C (p=0.17) did not show a significant difference although lower levels were observed in the luteal phase of TG and VLDL-C and higher levels for HDL-C.

CONCLUSION

The present findings reveal high levels of oestrogen in the luteal phase compared to follicular phase of menstrual cycle. Clinicians should take menstrual cycle phase in account when inferring a women biomarker measurement in the analysis of cardiovascular diseases, particularly females possessing marginal levels. Moreover research studies should take the menstrual cycle phase in consideration which may be a confounding factor in framing and concluding studies on reproductive age group women.

Associations of Steroid Sex Hormones and Sex Hormone-Binding Globulin With the Risk of Type 2 Diabetes in Women: A Population-Based Cohort Study and Meta-analysis

It remains unclear whether endogenous sex hormones (ESH) are associated with risk of type 2 diabetes (T2D) in women. Data of 3,117 postmenopausal women participants of the Rotterdam Study were analyzed to examine whether ESH and sex hormone-binding globulin (SHBG) were associated with the risk of incident T2D. Additionally, we performed a systematic review and meta-analysis of studies assessing the prospective association of ESH and SHBG with T2D in women. During a median follow-up of 11.1 years, we identified 384 incident cases of T2D in the Rotterdam Study. No association was observed between total testosterone (TT) or bioavailable testosterone (BT) with T2D. SHBG was inversely associated with the risk of T2D, whereas total estradiol (TE) was associated with increased risk of T2D. Similarly, in the meta-analysis of 13 population-based prospective studies involving more than 1,912 incident T2D cases, low levels of SHBG and high levels of TE were associated with increased risk of T2D, whereas no associations were found for other hormones. The association of SHBG with T2D did not change by menopause status, whereas the associations of ESH and T2D were based only in postmenopausal women. SHBG and TE are independent risk factors for the development of T2D in women.

Anti-climacterium effects of pomegranate concentrated solutions in ovariectomized ddY mice

In the present study, the complex anti-climacterium potential of standardized pomegranate concentrated solution (PCS) was investigated using bilateral ovariectomy (OVX) female ddY mice. Changes in body weight and gain during experimental periods, food consumption, serum estradiol levels, total body and abdominal fat densities, abdominal fat pads, and uterus weights were observed, along with the histopathology of abdominal fat pads and uterus for anti-obesity and estrogenic effects. In addition, liver weights, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels, and histopathological inspections were performed to explore the hepato-protective effects. Serum total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein, and triglyceride (TG) levels were monitored for hypolipidemic effects with total body and femur mean bone mineral density (BMD), right femur wet, dry and ash weights, strength, serum osteocalcin, bone-specific alkaline phosphatase (bALP) contents, and histological and histomorphometrical analyses for anti-osteoporosis activity. As a result of OVX, notable increases in body weight and gains, food consumption, abdominal fat mass densities, weights of abdominal fat pads deposited in the abdominal cavity, and serum AST, ALT, TC, LDL, TG, and osteocalcin levels were observed, along with decreases in the uterus, liver, and femur weights, mean total body and femur BMD, femur strength, serum bALP, and estradiol levels. In addition, marked hypertrophic alterations in adipocytes located in the deposited abdominal fat pads, liver steatosis, uterine disused atrophic changes, and decreases in bone mass and structures of the femur were also observed in OVX control mice with significant increases in bone resorption markers based on histopathological and histomorphometrical analysis. However, these estrogen-deficient climacterium symptoms were significantly (P<0.05 or P<0.01) inhibited after 84 days of continuous treatment with estradiol and PCS (1, 2 and 4 ml/kg), respectively. The present results suggested that PCS was able to effectively inhibit or refine the climacterium symptoms, including obesity, hyperlipidemia, hepatic steatosis, and osteoporosis, induced by OVX in ddY mice.

Effects of Oxidative Stress and Testosterone on Pro-Inflammatory Signaling in a Female Rat Dopaminergic Neuronal Cell Line

Parkinson's disease, a progressive neurodegenerative disorder, is associated with oxidative stress and neuroinflammation. These pathological markers can contribute to the loss of dopamine neurons in the midbrain. Interestingly, men have a 2-fold increased incidence for Parkinson's disease than women. Although the mechanisms underlying this sex difference remain elusive, we propose that the primary male sex hormone, testosterone, is involved. Our previous studies show that testosterone, through a putative membrane androgen receptor, can increase oxidative stress-induced neurotoxicity in dopamine neurons. Based on these results, this study examines the role of nuclear factor κ B (NF-κB), cyclooxygenase-2 (COX2), and apoptosis in the deleterious effects of androgens in an oxidative stress environment. We hypothesize, under oxidative stress environment, testosterone via a putative membrane androgen receptor will exacerbate oxidative stress-induced NF-κB/COX2 signaling in N27 dopaminergic neurons, leading to apoptosis. Our data show that testosterone increased the expression of COX2 and apoptosis in dopamine neurons. Inhibiting the NF-κB and COX2 pathway with CAPE and ibuprofen, respectively, blocked testosterone's negative effects on cell viability, indicating that NF-κB/COX2 cascade plays a role in the negative interaction between testosterone and oxidative stress on neuroinflammation. These data further support the role of testosterone mediating the loss of dopamine neurons under oxidative stress conditions, which may be a key mechanism contributing to the increased incidence of Parkinson's disease in men compared with women.

Association of Serum Sex Hormones with Hemostatic Factors in Women On and Off Hormone Therapy: The Multiethnic Study of Atherosclerosis

BACKGROUND

Hormone therapy (HT) is associated with increased risk of both venous and arterial thrombosis, which are multifactorial in origin.

OBJECTIVES

Our objectives were twofold: first, we sought to examine associations between endogenous serum sex hormone levels and biomarkers of thrombosis and/or coagulation in postmenopausal hormone nonusers. Second, we separately studied the associations between serum sex hormone levels and biomarkers of thrombosis and/or coagulation in postmenopausal hormone users considering the fact that pattern of circulating hormones is different in women taking exogenous hormones.

PATIENTS/METHODS

We performed a cross-sectional analysis of postmenopausal women enrolled in a large multiethnic community-based cohort study, The Multiethnic Study of Atherosclerosis. We hypothesized that higher levels of estrogen-related sex hormones would be associated with biomarkers of thrombosis, suggesting mechanisms for differences in thrombotic risk from HT. Women (n = 2878) were included if they were postmenopausal and had thrombotic biomarkers (homocysteine, fibrinogen, C-reactive protein [CRP], factor VIII, and d-dimer) and sex hormone levels (total testosterone [T], bioavailable testosterone, sex hormone binding globulin [SHBG], estradiol [E2], and dehydroepiandrosterone [DHEA]) measured. A smaller random sample of 491 women also had von Willebrand factor (vWF), plasminogen activator inhibitor (PAI-1), and tissue factor pathway inhibitor (TFPI) levels measured.

RESULTS AND CONCLUSIONS

We found that elevated levels of estradiol and SHBG in HT users were associated with elevated levels of CRP and lower levels of TFPI, both of which may be related to a prothrombotic milieu in HT users. HT nonusers had far more prothrombotic associations between elevated serum sex hormone levels and thrombotic biomarkers when compared with HT users.

Cardiovascular risk factors and events in women with androgen excess

Androgen excess (AE) was approximated to be present in 7% of the adult population of women. Polycystic ovary syndrome (PCOS) is the most prevalent among them, followed by idiopathic hirsutism (IH), congenital adrenal hyperplasia (CAH), hyperandrogenic insulin-resistant acanthosis nigricans (HAIRAN) syndrome, and androgen-secreting neoplasms (ASNs). Increased cardiovascular risk was implicated in women with AE. Serum testosterone independently increases risk for cardiovascular disease (CVD), and correlates even with indices of subclinical atherosclerosis in various populations of postmenopausal women. Hyperandrogenism in PCOS is closely related to the aggravation of abdominal obesity, and together with insulin resistance forming the metabolic core for the development of CVD. However, phenotypic variability of PCOS generates significant influence on the cardiometabolic risks. Numerous risk factors in PCOS lead to 5-7 times higher risk for CVD and over 2-fold higher risk for coronary heart disease and stroke. However, issue on the cardiometabolic risk in postmenopausal women with hyperandrogenic history is still challenging. There is a significant overlapping in the CVD characteristics of women with PCOS and variants of CAH. Relevant clinical data on the prevalence and cardiometabolic risk and events in women with IH, HAIRAN syndrome or ASNs are scarce. The effects of various oral contraceptives (OCs) and antiandrogenic compounds on metabolic profile are varying, and could be related to the selected populations and different therapy regiments mainly conducted in women with PCOS. It is assumed relation of OCs containing antiandrogenic progestins to the increased risk of cardiovascular and thromboembolic events.

Sustained use of biogas fuel and blood pressure among women in rural Nepal

BACKGROUND

More than two fifths of the world's population cook with solid fuels and are exposed to household air pollution (HAP). As of now, no studies have assessed whether switching to alternative fuels like biogas could impact cardiovascular health among cooks previously exposed to solid fuel use.

METHODS

We conducted a propensity score matched cross-sectional study to explore if the sustained use of biogas fuel for at least ten years impacts blood pressure among adult female cooks of rural Nepal. We recruited one primary cook ≥ 30 years of age from each biogas (219 cooks) and firewood (300 cooks) using household and measured their systolic (SBP) and diastolic blood pressure (DBP). Household characteristics, kitchen ventilation and 24-h kitchen carbon monoxide were assessed. We matched cooks by age, body mass index and socio-economic status score using propensity scores and investigated the effect of biogas use through multivariate regression models in two age groups, 30-50 years and >50 years to account for any post-menopausal changes.

RESULTS

We found substantially reduced 24-h kitchen carbon monoxide levels among biogas-using households. After matching and adjustment for smoking, kitchen characteristics, ventilation status and additional fuel use, the use of biogas was associated with 9.8 mmHg lower SBP [95% confidence interval (CI), -20.4 to 0.8] and 6.5 mmHg lower DBP (95% CI, -12.2 to -0.8) compared to firewood users among women >50 years of age. In this age group, biogas use was also associated with 68% reduced odds [Odds ratio 0.32 (95% CI, 0.14 to 0.71)] of developing hypertension. These effects, however, were not identified in younger women aged 30-50 years.

CONCLUSIONS

Sustained use of biogas for cooking may protect against cardiovascular disease by lowering the risk of high blood pressure, especially DBP, among older female cooks. These findings need to be confirmed in longitudinal or experimental studies.

Menopause versus aging: The predictor of obesity and metabolic aberrations among menopausal women of Karnataka, South India

Context:

Increased incidences of cardiovascular disorder and metabolic syndrome particularly after menopause have raised curiosity for the underlying factors. However, it is still a debate whether age or menopausal transition is a greater contributor.

Aims:

To elucidate the inter-relationships of age, menopause, and associated obesity and to assess their independent effects on aggravation of cardio metabolic risk factors in postmenopausal women.

Settings and Design:

Four hundred two women aged between 30 and 75 years were recruited in a cross-sectional study from Southern India. Three hundred sixteen participants exempting exclusion criteria, comprising of 169 premenopausal and 147 postmenopausal women were finally included.

Materials and Methods:

Anthropometric measurements such as weight, height, waist circumference (WC), hip circumference (HC), fat percentage, basal metabolic rate (BMR), and blood pressure were taken. Fasting plasma glucose, postprandial glucose, glycated hemoglobin (HbA1c), lipid profile, and C-reactive protein (CRP) were also measured.

Statistical Analysis Used:

Independent t-test, Analysis of covariates (ANCOVA), Pearson's correlation coefficients and multiple stepwise linear regression model analysis were done.

Results:

A significant increase in physical and metabolic factors was observed in postmenopausal women compared to premenopausal women except WC and HbA1c. Contrastingly, high-density lipoprotein cholesterol (HDL) levels and BMR were significantly decreased. After adjusting for BMI and age, the significant differences in the variables through the menopausal transition persisted, including an increase in WC. Significant correlation was observed between age and measures of general obesity such as BMI (P < 0.05) and fat percentage (P < 0.001) but not with central obesity indices. Menopausal status and WC exerted an independent effect on most of the metabolic risk factors (P < 0.001 or P < 0.01). Fat percentage was the predicting variable for CRP, HbA1c, diastolic blood pressure (P < 0.001), and HDL (P < 0.01). But Age showed independent effect only on HbA1c.

Conclusions:

Menopausal transition brings about anomalies in total body composition characterized by an increased body fat mass and central adiposity. This creates a compatible atmosphere for abnormal metabolism and aggravated cardio metabolic risk factors. Thus, menopausal status and associated obesity is the major predictor of metabolic aberrations over age in menopausal women.

Asthma and the menopause: a systematic review and meta-analysis

OBJECTIVE

To review the available literature to determine whether the menopausal transition is associated with asthma incidence.

METHODS

We performed a systematic review and meta-analysis of cohort and cross-sectional studies providing a definition/assessment of menopausal status, incidence or prevalence of a defined diagnosis of asthma, and providing a measure of the association or of menopausal state and asthma or enough data for a calculation of this association. Where possible these meta-analytic estimates were also stratified by intake of menopausal hormone therapy (MHT).

RESULTS

Of 76 potentially relevant articles, 8 studies met the inclusion criteria and were included in the review, and 6 in the meta-analysis. There was heterogeneity across studies: four studies reported slightly increased prevalence rates of asthma in post-menopause, one large cohort yielded a lower asthma incidence and one cross-sectional study a lower prevalence in post-menopause. Overall, the meta-analysis showed no significant association between menopause and asthma rates. When stratifying by use of MHT, the association between menopause and asthma rates was increased in women reporting use of MHT (RR 1.32, 95%CI 1.01-1.74), but not in women not using MHT.

CONCLUSION

We found no significant association of menopause with asthma prevalence or incidence except for women reporting use of MHT. However, these findings result from a small number of studies, including only 1 large cohort with incidence rates for pre- as well as post-menopause. Further studies are needed addressing more closely subgroup analyses and a possible modification of the association of menopause and asthma by MHT.

Stroke risk in women: the role of menopause and hormone therapy

Although women have a lower risk of stroke during middle age than men, the menopausal transition is a time when many women develop cardiovascular risk factors. Additionally, during the 10 years after menopause, the risk of stroke roughly doubles in women. Endogenous oestrogen concentrations decline by 60% during the menopausal transition, leading to a relative androgen excess, which could contribute to the increased cardiovascular risk factors in women. Earlier onset of menopause might affect the risk of stroke, but the data are not clear. Because of the stroke risk associated with it, hormone therapy is recommended only for treatment of vasomotor symptoms, and some formulations might be safer than others. More research is needed to understand which women are at greatest stroke risk during midlife and to identify the safest formulation, dose, and duration of hormone therapy that can be used to treat vasomotor symptoms without increasing the risk of stroke.

Gender differences in artery wall biomechanical properties throughout life

Elevated large artery stiffness and pulse pressure have emerged as important risk factors for cardiovascular disease. The genders differ in large artery biomechanical properties throughout the lifespan with females displaying higher stiffness than males during the prepubertal years and a dramatic increase after menopause. Males on the other hand experience an increase in arterial stiffness postpuberty and a linear increase thereafter, suggesting that females have intrinsically stiffer large arteries than males, but that such effects are mitigated by sex steroids during the reproductive years. This review discusses anthropometric and sex steroid influences on gender differences in large artery stiffness and pressure dynamics from childhood to senescence. In particular, the sex-specific effects of estrogen, progesterone and testosterone on vascular structure and function and how these influence arterial stiffness are explored. These factors may contribute in part to the observed gender differences in the pathophysiology and clinical manifestations of cardiovascular disease.

Regulation of LKB1 expression by sex hormones in adipocytes

OBJECTIVE

In the adipose tissue, activation of AMP-activated protein kinase (AMPK) by phosphorylation favours local fatty acid oxidation and inhibition of lipogenesis. We have previously shown that the potent androgen dihydrotestosterone (DHT) can inhibit phosphorylation of AMPK in adipose tissue and 3T3-L1 adipocytes in a dose-dependent manner. This negative effect of DHT was reversed by oestrogen treatment. The purpose of this current study was to determine the underlying mechanisms whereby androgens and oestrogens can regulate AMPK phosphorylation in adipocytes, and whether this mechanism is receptor dependent.

RESULTS

Phosphorylation of AMPK was assessed by western blot in cells treated for 24 h with testosterone or DHT (1-1000 nM). Testosterone and DHT significantly inhibited basal phosphorylation of AMPK. Addition of the androgen receptor antagonist Flutamide (1 μM) to the media reversed the negative effect of testosterone and DHT by returning AMPK phosphorylation levels to those of basal. To further dissect the mechanism underlying AMPK inhibition by testosterone or DHT, we examined the mRNA expression of the upstream activator of AMPK, namely LKB1. Testosterone and DHT treatment of murine 3T3-L1 or human SGBS adipocytes for 24 h significantly decreased the mRNA expression of LKB1. In contrast, 17β-estradiol treatment increased LKB1 mRNA, an effect mediated by oestrogen receptor alpha.

CONCLUSION

We conclude that regulation of AMPK phosphorylation by androgens and oestrogens is receptor-dependent, and demonstrate for the first time that LKB1 is regulated by sex hormones in adipocytes.

Effect of ovarian aging on androgen biosynthesis in a cynomolgus macaque model

OBJECTIVE

The role of androgens in chronic disease pathogenesis, cognitive function and libido during menopause is of increasing interest. The aim of this study was to characterize the distribution and expression of androgenic proteins in the macaque ovary and to investigate the relationship between serum androgen concentrations, follicle number, and the persistence of androgenesis in the aging macaque ovary.

METHODS

The subjects were 26 adult female cynomolgus macaques. Ovaries were immunostained for cytochrome P450 17α-hydroxylase/17-20 lyase (P450c17), 3β-hydroxysteroid dehydrogenase (3βHSD), and cytochrome b5 (cytb5). Based on primordial follicle counts, animals were divided into tertiles (low (≤200), intermediate (226-1232), and high (2372-4356)) to evaluate differences in androgen staining and changes in serum androgen concentrations following ovariectomy.

RESULTS

Positive immunostaining for P450c17 and cytb5 within the theca interna layer of growing follicles persisted in advanced atretic follicles and secondary interstitial cells (residual stromal cells). Ovaries with low follicle numbers had less staining for all androgenic proteins compared to ovaries with higher numbers of growing follicles. Immunostaining for cytb5 was the most reliable marker for persistent androgenesis in ovaries with minimal primordial follicle numbers (<100) and residual stromal cells. Following ovariectomy, a significant decrease in testosterone (-27.7%, -30.8%, -27.5%; p < 0.01) and androstenedione (-33.4%, -35.7%, -46.0%; p < 0.01) was observed in monkeys with low, intermediate, and high primordial follicle counts, respectively.

CONCLUSIONS

Despite low follicle numbers, the aging macaque ovary retains the necessary proteins for androgenesis within residual stromal cells and contributes to peripheral androgen concentrations.

Hormone therapy and stroke: is it all about timing?

Although women have a lower incidence of stroke than men in most age groups, women have an overall increased lifetime risk of stroke. Women also have unique risk factors for stroke, including the menopausal transition, the existence of debilitating vasomotor symptoms for some women, and the issues related to hormonal treatment for those symptoms. Although the initial studies of hormone therapy (HT) use in postmenopausal women suggested significant protection against heart disease, there was no obvious protection against stroke. Randomized trials of HT for secondary prevention showed a lack of benefit for both heart disease and stroke, and the suggestion of some early risk after initiation. However, the Women's Health Initiative (WHI), a primary prevention study of the impact of HT on women aged 50 to 79 years, showed an increased risk of stroke, whether the HT was estrogen alone or estrogen combined with progestin. Therefore, HT is not recommended for stroke prevention, and it appears to cause harm. The reason for this increased stroke risk is not understood, but some have suggested that the initiation of HT closest to the time of menopausal transition should decrease the risk. Although there was a lower risk of heart disease when HT was initiated earlier, the risk appeared to be the same for stroke regardless of the timing. This was shown in both the WHI and the Nurses' Health Study cohorts. Therefore, more research is needed to understand the mechanisms for the increased stroke risk and to identify those who may be at risk because of HT for vasomotor symptoms, atrophic vaginitis, or osteoporosis, the three remaining indications for HT use in women. Trials are under way to assess the intermediate outcomes of HT on subclinical vascular disease in perimenopausal/early postmenopausal women.

Assessing cardiovascular risk in Mediterranean women with polycystic ovary syndrome

BACKGROUND

Although dyslipidemia is common in the polycystic ovary syndrome (PCOS), current diagnostic guidelines suggest to evaluate only plasma HDL-cholesterol and triglyceride concentrations, assuming that, in this disorder, cardiovascular risk is mainly due to the presence of the metabolic syndrome (MS). In the US, MS has been found in up to 50% of PCOS, but in other countries its prevalence is lower.

METHODS

We compared the prevalence of MS with that of increased LDL- and non-HDL-cholesterol levels in 350 Mediterranean PCOS women (244 anovulatory and 106 ovulatory), and 95 normo-weight and 90 body mass index (BMI)- matched controls.

RESULTS

The prevalence of MS was 7.1% in PCOS, higher than normoweight and BMI-matched controls (2.4% and 3.5%, respectively, p < 0.05 for both). The prevalence of elevated LDL- and non-HDL-cholesterol levels in PCOS was respectively, 14.9% and 8.6%, higher than normoweight (2.1% and 1.0%, respectively, p < 0.01 for both) and BMI-matched controls (4.4% and 2.2%, respectively, p<0.05 for both). In PCOS, increased LDL-cholesterol was twice more prevalent than MS or non-HDL-cholesterol. Only a minority of PCOS with MS had increased LDL-cholesterol while increased non-HDL-cholesterol was generally associated to increased LDL-cholesterol.

CONCLUSIONS

We have found that in Mediterranean PCOS the prevalence of MS is relatively low while elevated LDL-cholesterol levels are more prevalent. Therefore, beyond MS, a more comprehensive lipid evaluation, including LDL-cholesterol, is needed for a more effective assessment of cardiovascular risk in PCOS.

SHBG, sex hormones, and inflammatory markers in older women

CONTEXT

In premenopausal and older women, high testosterone and estradiol (E2) and low SHBG levels are associated with insulin resistance and diabetes, conditions characterized by low-grade inflammation.

OBJECTIVE

The aim of the study was to examine the relationship between SHBG, total testosterone, total E2, and inflammatory markers in older women.

DESIGN AND PATIENTS

We conducted a retrospective cross-sectional study of 433 women at least 65 yr old from the InCHIANTI Study, Italy, who were not on hormone replacement therapy or recently hospitalized and who had complete data on SHBG, testosterone, E2, C-reactive protein (CRP), IL-6, soluble IL-6 receptor (sIL-6r), and TNF-α. Relationships between sex hormones and inflammatory markers were examined by multivariate linear regression analyses adjusted for age, body mass index, smoking, insulin, physical activity, and chronic disease.

RESULTS

In fully adjusted analyses, SHBG was negatively associated with CRP (P = 0.007), IL-6 (P = 0.008), and sIL-6r (P = 0.02). In addition, testosterone was positively associated with CRP (P = 0.006), IL-6 (P = 0.001), and TNF-α (P = 0.0002). The negative relationship between testosterone and sIL-6r in an age-adjusted model (P = 0.02) was no longer significant in a fully adjusted model (P = 0.12). E2 was positively associated with CRP (P = 0.002) but not with IL-6 in fully adjusted models. In a final model including E2, testosterone, and SHBG, and all the confounders previously considered, SHBG (0.23 ± 0.08; P = 0.006) and E2 (0.21 ± 0.08; P = 0.007), but not testosterone (P = 0.21), were still significantly associated with CRP.

CONCLUSION

In late postmenopausal women not on hormone replacement therapy, SHBG and E2 are, respectively, negative and positive, independent and significant correlates of a proinflammatory state.

Gender differences in the cardiovascular effects of sex hormones

Over the last decade, compelling evidence supports the idea that the different impact of cardiovascular disease (CVD) and the differences in vascular biology in men and women may be, at least in part, related to the cardiovascular and metabolic effects of sex steroid hormones. Indeed, androgens and oestrogens influence a multitude of vascular biological processes and their cardiovascular effects are multifaceted. While in women the effects of androgens mainly depend upon oestrogens' levels and, ultimately, upon the estradiol/testosterone ratio, the effects of androgens in men mostly relate to their aromatization into oestrogens. Oestrogens exert potential beneficial effects on the cardiovascular system in both sexes. In women, the effect of oestrogens, alone or in association with progestins, has been widely investigated, but data obtained from older patient populations have lead the medical community and the general public to misleading conclusions. Growing evidence supports the 'timing hypothesis', which suggests that oestrogen/hormone replacement therapy may increase CVD risk if started late after menopause, but produce beneficial cardiovascular effects in younger postmenopausal women. Because in men adequate interventional studies with testosterone are lacking, specific investigations should be performed.

Androgens associated with advanced glycation end-products in postmenopausal women

OBJECTIVE

Higher frequency of subclinical atherosclerosis has been linked with androgen levels in postmenopausal women. Advanced glycation end-products (AGEs) are well-recognized atherogenic molecules. Therefore, we investigated the association of postmenopausal sex steroid and metabolic status with serum AGE levels.

METHODS

Serum sex hormones, fasting glucose, fasting insulin, and AGEs were assessed in 106 healthy postmenopausal women. Insulin resistance was estimated by using the homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

Women in the highest testosterone quartile (Q4) had higher serum AGE levels (Q1, 5.22 IU/mL ± 0.50; Q2, 5.08 ± 0.53 IU/mL; Q3, 5.78 ± 1.10 IU/mL vs Q4, 7.35 ± 1.23 IU/mL; P < 0.0005) compared with women in the lowest testosterone quartiles. Accordingly, women in the highest free androgen index (FAI) quartile had higher serum AGE levels (Q1, 5.36 ± 0.59 IU/mL; Q2, 5.28 ± 0.72 IU/mL vs Q4, 6.68 ± 1.48 IU/mL; P < 0.0005) compared with women in the lowest FAI quartile. These findings remained significant after adjustment for age, body mass index, HOMA-IR, and fasting glucose and fasting insulin levels. A highly significant correlation was found for testosterone and FAI with AGEs and persisted after adjustment for age, body mass index, HOMA-IR, and fasting glucose and fasting insulin levels (r = 0.67, P < 0.0005)

CONCLUSIONS

The data from the current study suggest that higher levels of AGEs are positively associated with higher androgen levels. This association, identified for the first time, may provide an additional insight into the pathophysiological mechanisms linking the described higher prevalence of cardiovascular events with higher androgen levels in postmenopausal women.

Lipid levels in polycystic ovary syndrome: systematic review and meta-analysis

OBJECTIVE

To quantify the magnitude and pattern of low-density lipoprotein (LDL) cholesterol and nonhigh-density lipoprotein (HDL) cholesterol levels in women with polycystic ovary syndrome (PCOS) versus control women.

DESIGN

Systematic review and meta-analysis of lipid levels in published cross-sectional studies worldwide where PCOS women and controls were examined and sampled.

MAIN OUTCOME MEASURE(S)

Differences in plasma lipids (including triglycerides, HDL-cholesterol, LDL-cholesterol, and nonHDL-cholesterol) in PCOS versus control subjects were calculated. Comparisons were made with and without body mass index (BMI) matching.

RESULT(S)

Triglyceride levels were 26 mg/dL (95% confidence interval [CI] 17-35) higher and HDL-cholesterol concentrations 6 mg/dL (95% CI 4-9) lower in women with PCOS. Also, LDL-cholesterol and nonHDL-cholesterol concentrations were higher in PCOS: by 12 mg/dL (95% CI 10-16) and 19 mg/dL (95% CI 16-22), respectively. With BMI matching, LDL-cholesterol and nonHDL-cholesterol were still higher in PCOS: by 9 mg/dL (95% CI 6-12) and 16 mg/dL (95% CI 14-19), respectively. LDL-cholesterol and nonHDL-cholesterol differences were greater with National Institutes of Health criteria [15 mg/dL (95% CI 13-17) and 21 mg/dL (95% CI 16-25), respectively] versus Rotterdam criteria [8 mg/dL (95% CI 5-12) and 17 (95% CI 13-22), respectively].

CONCLUSION(S)

Dyslipidemia is common in PCOS. Beyond known alterations in triglycerides and HDL-cholesterol, women with PCOS have higher LDL-cholesterol and nonHDL-cholesterol, regardless of BMI. We recommend that all women with PCOS be screened for dyslipidemia, including LDL-cholesterol and nonHDL-cholesterol determinations, for effective cardiovascular risk prevention.

A single dose of dihydrotestosterone induced a myogenic transcriptional program in female intra-abdominal adipose tissue

Sex steroids are key regulators of adipose tissue (AT) mass, determining gender-specific differences in fat distribution and accumulation. With the aim of exploring the relevance and peculiarities of androgen action in female intra-abdominal AT, we used the serial analysis of gene expression (SAGE) method to analyze the AT transcriptome in four groups of female mice: intact, ovariectomized (OVX), OVX plus dihydrotestosterone (DHT) injection at 3h or 24h before sacrifice (DHT3h, DHT24h). An average of 19555 transcript species was examined in retroperitoneal fat. We found a total of 321 transcripts differentially modulated by DHT and OVX, including 125 novel genes. Several genes involved in energy metabolism/ATP production were up-regulated by DHT, whereas important regulators of lipid metabolism were reduced. Transcripts involved in Ca(2+) uptake/release, cell signalling, cell defence and protein expression were differentially modulated by DHT. A surprising number of myogenic genes were up-regulated, including myosin light and heavy polypeptides, troponins, as well as several actin-binding proteins. These results suggest that DHT24h may have induced a myogenic-like transcriptional program in adipocytes. The present study sheds light on the distinctive female transcriptional pattern acutely induced by androgens in intra-abdominal fat, and may add new insights into the global understanding of menopausal endocrinology and its association to intra-abdominal obesity.

Retaining Residual Ovarian Tissue following Ovarian Failure Has Limited Influence on Bone Loss in Aged Mice

Previous work showed that retaining residual ovarian tissue protects young mice from accelerated bone loss following ovarian failure. The present study was designed to determine whether this protection is also present in aged animals. Aged (9-12 months) C57BL/6Hsd female mice were divided into: CON (vehicle), VCD (160 mg/kg; 15d), or OVX (ovariectomized). Lumbar BMD was monitored by DXA and μCT used to assess vertebral microarchitecture. BMD was not different between VCD and CON at any time point but was lower (P < .05) than baseline, starting 1 month after ovarian failure in VCD and OVX mice. Following μCT analysis there were no differences between CON and VCD, but OVX mice had lower bone volume fraction, trabecular thickness, and a trend for decreased connectivity density. These findings provide evidence that retention of residual ovarian tissue may protect aged follicle-depleted mice from accelerated bone loss to a lesser extent than that observed in young mice.

Extremes of endogenous testosterone are associated with increased risk of incident coronary events in older women

CONTEXT

Few studies have examined whether endogenous testosterone is associated with the development of coronary heart disease (CHD) in women.

OBJECTIVE

This study tested the association of total testosterone (total T) and bioavailable T (BioT) levels with risk of incident coronary events among older community-dwelling women.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective, population-based study of 639 postmenopausal women, aged 50-91 (mean, 73.8) yr who had serum testosterone measurements at baseline (1984-87) and who were followed for incident CHD events through 2004.

MAIN OUTCOME MEASURES

A total of 134 incident CHD events occurred during follow-up [45 nonfatal myocardial infarctions, 79 fatal myocardial infarctions, and 10 coronary revascularizations].

RESULTS

The median follow-up was 12.3 yr. Age-adjusted CHD risk estimates were similar for the four highest total T quintiles relative to the lowest, suggesting a low threshold. In age-adjusted analyses, the lowest total T quintile (</=80 pg/ml) was associated with a 1.62-fold increased risk of incident CHD [95% confidence interval (CI), 1.10-2.39] compared to higher levels. BioT showed a U-shaped association with incident CHD. Age-adjusted risk for the lowest and highest BioT quintiles relative to the third were 1.79 (95% CI, 1.03-3.16) and 1.96 (95% CI, 1.13-3.41), respectively. Additional adjustment for lifestyle, adiposity, estradiol, and ovarian status, or for CHD risk factor covariates, had minimal influence on results.

CONCLUSIONS

An optimal range of testosterone may exist for cardiovascular health in women, with increased risk of CHD events at low levels of testosterone overall and at high levels of the bioavailable fraction of testosterone.