Endogenous testosterone and endothelial function in postmenopausal women

Higher testosterone is associated with higher HDL-cholesterol and lower triglyceride concentrations in older women: an observational study

OBJECTIVE

This study aimed to determine whether concentrations of testosterone and its main precursor after menopause, dehydroepiandrosterone (DHEA), are associated with lipoproteins and other lipids in community-dwelling older women.

METHODS

The Sex Hormones in Older Women (SHOW) study was an observational study of 6358 Australian women, aged at least 70 years, with no prior major adverse cardiovascular event who had sex hormones measured by liquid chromatography-tandem mass spectrometry. Associations between hormones and lipids were examined using multilinear regression adjusted for potential confounders.

RESULTS

The cross-sectional analyses included 3231 participants, median age 74.0 (interquartile range 71.7-77.9) years. Compared with concentrations in the lowest quartile (Q1), testosterone concentrations in the highest quartiles (Q3 and Q4) were positively associated with high-density lipoprotein cholesterol (HDL-C) (p = 0.002 and p < 0.001, respectively) while Q4 testosterone concentrations were positively associated with total cholesterol (p = 0.038). Q2, Q3 and Q4 testosterone concentrations were significantly inversely associated with triglycerides (TG) (p = 0.024, p = 0.003 and p < 0.001, respectively). For DHEA, Q4 concentrations was positively associated with non-HDL-C (p = 0.024).

CONCLUSIONS

In older women, higher endogenous testosterone concentrations are significantly associated with higher HDL-C and lower TG, indicating a less atherogenic profile. These findings suggest a neutral, or potentially protective, cardiovascular disease effect of testosterone in older women.

Testosterone therapy in females is not associated with increased cardiovascular or breast cancer risk: a claims database analysis

BACKGROUND

Testosterone therapy (TTh) has been shown to improve libido in women with sexual dysfunction, but its utilization has been limited due to concern for cardiovascular events and past studies reporting highly variable results.

AIM

To assess the association of TTh in women with major adverse cardiac events (MACEs), including heart attack, stroke, or death, using a large database.

METHODS

The TriNetX Diamond Network was queried from 2009 to 2022. Our study cohort included adult females with ≥3 systemic testosterone prescriptions within a year. Our control cohort excluded females with any testosterone prescriptions, polycystic ovary syndrome, or androgen excess. Both cohorts excluded females with prior heart failure, unstable angina, intersex surgery (female to male), personal history of sex reassignment, or gender identity disorders. Propensity matching between the cohorts was performed. A subanalysis by age was conducted (18-55 and >55 years).

OUTCOMES

We evaluated the association of TTh to the following: MACE, upper or lower emboli or deep vein thrombosis (DVT), pulmonary embolism (PE), breast neoplasm, and hirsutism within 3 years of TTh.

RESULTS

When compared with propensity-matched controls, adult females with TTh had a lower risk of MACE (risk ratio [RR], 0.64; 95% CI, 0.51-0.81), DVT (RR, 0.61; 95% CI, 0.42-0.90), PE (RR, 0.48; 95% CI, 0.28-0.82), and malignant breast neoplasm (RR, 0.48; 95% CI, 0.37-0.62). Similarly, females aged 18 to 55 years with TTh had a lower risk of MACE (RR, 0.49; 95% CI, 0.28-0.85) and DVT (RR, 0.48; 95% CI, 0.25-0.93) and a similar risk of malignant breast neoplasm (RR, 0.62; 95% CI, 0.34-1.12). Females aged ≥56 years with TTh had a similar risk of MACE (RR, 0.84; 95% CI, 0.64-1.10), DVT (RR, 0.82; 95% CI, 0.50-1.36), and PE (RR, 0.52; 95% CI, 0.26-1.05) and a significantly lower risk of malignant breast neoplasm (RR, 0.51; 95% CI, 0.38-0.68). Risk of hirsutism was consistently higher in those with TTh as compared with propensity-matched controls.

CLINICAL IMPLICATIONS

Our results contribute to safety data on TTh, a therapy for sexual dysfunction in women.

STRENGTHS AND LIMITATIONS

The TriNetX Diamond Network allows for significant generalizability but has insufficient information for some factors.

CONCLUSIONS

We found a decreased risk of MACE among women with TTh as compared with matched controls and a similar risk of MACE in postmenopausal women while demonstrating a similar or significantly lower risk of breast cancer on age-based subanalysis.

Testosterone and the heart: friend or foe?

Cardiovascular disease (CVD) is the leading cause of death in women aged 65 years and older. Sex hormones have been implicated as having a critical role in the evolution of CVD, with the focus mainly on estrogens in women. Available data also indicate that low testosterone blood levels may be detrimental to cardiovascular function in women. At blood concentrations considered normal for premenopausal women, testosterone has favorable effects on blood vessel function (relaxation and contraction), much of which is determined by the endothelial cells that line the inside of blood vessels. Testosterone enhances endothelium-dependent and independent brachial artery vasodilation and has an acute systolic blood pressure-lowering effect in postmenopausal women. Advantageous effects of testosterone in animal models have been seen for myocardial function and cardiac electrical signaling. Human data are mainly limited to observational and mechanistic studies, which mostly demonstrate beneficial effects of testosterone on cardiovascular health. Few studies of testosterone use in women, with cardiovascular endpoints as primary outcomes, have been published.

Endothelial and exercise vasodilation are reduced in postmenopausal females with obesity versus lean and overweight

BACKGROUND

Obesity (OB) is highly prevalent in females after menopause, especially visceral adipose tissue (VAT) accumulation which contributes to endothelial dysfunction. The endothelium assists in regulating blood flow (BF) during exercise and is attenuated in females with OB. The purpose of this study was to examine upper and lower limb flow-mediated dilation (FMD) and BF regulation during graded low-intensity submaximal exercises in postmenopausal females with BMI in the lean (LN), overweight (OW) and OB categories.

METHODS

Participants were grouped by body mass index (BMI) into LN (BMI 18.5-24.9 kg/m2; n = 11), OW (BMI 25.0-29.9 kg/m2; n = 15), and OB (BMI 30.0-39.9 kg/m2; n = 13). FMD of the brachial (BA-FMD) and superficial femoral arteries (FA-FMD) were assessed. Subsequently, BF and vascular conductance (VC) in the upper (BA-BF and BA-VC) and lower limbs (FA-BF and FA-VC) were measured during separate 3-stage incremental rhythmic handgrip and plantarflexion exercises.

RESULTS

Significantly lower FA-FMD (P < 0.05) were seen in OB than LN and OW groups with no differences in BA-FMD. Increases in FA-BF and FA-VC were attenuated during the last stage of plantarflexion exercise at 30% of 1RM in OB (both P < 0.001) compared to LN and OW, while upper-body exercise vasodilation was unchanged. FA-BF and FA-VC during plantarflexion exercise were correlated to FA-FMD (FA-BF: r = 0.423, P = 0.007, FA-VC: r = 0.367, P = 0.021) and BMI (FA-BF: r = -0.386, P = 0.015, FA-VC: r = -0.456, P = 0.004).

CONCLUSION

Postmenopausal females with OB have reduced lower-limb endothelial and exercise vasodilator function during submaximal dynamic plantarflexion exercise compared to LN and OW. Our findings indicate that obesity may predict diminished leg endothelial function, BF and VC during exercise in postmenopausal females.

Testosterone Replacement Therapy in Relation With Cardiovascular Disease in Cisgender Women and Transgender People

AIMS

This study aimed to investigate the association of testosterone replacement therapy (TTh) with risk of cardiovascular disease (CVD), and CVD-specific outcomes, in cisgender women and transgender population, and to determine whether this association varies by menopausal status.

METHODS

In 25 796 cisgender women and 1580 transgender people (≥30 years old) who were enrolled in the Optum's deidentified Clinformatics Data Mart Database (2007-2021), we identified 6288 pre- and postmenopausal cisgender women and 262 transgender people diagnosed with incident composite of CVD (coronary artery disease [CAD], congestive heart failure, stroke, and myocardial infarction). Prediagnostic prescription of TTh was ascertained for this analysis. Multivariable adjusted Cox proportional hazards models were used to examine the independent association of TTh with incident CVD.

RESULTS

We found a 24% increased risk of CVD (hazard ratio [HR] = 1.24; 95% CI, 1.15-1.34), 26% risk of CAD (HR = 1.26; 95% CI, 1.14-1.39), and a 29% risk of stroke (HR = 1.29; 95% CI, 1.14-1.45) after comparing cisgender women who used TTh with nonusers. Stratification by age group showed similar effects of TTh on CVD, CAD, and stroke. Among transgender people, TTh did not increase the risk of composite CVD, including by age stratification.

CONCLUSION

Use of TTh increased the risk of CVD, CAD, and stroke among cisgender women but not among transgender people. TTh is becoming more widely accepted in women, and it is the main medical treatment for transgender males. Therefore, use of TTh should be further investigated for the prevention of CVD.

Gender-based research underscores sex differences in biological processes, clinical disorders and pharmacological interventions

Earlier research has presumed that the male and female biology is similar in most organs except the reproductive system, leading to major misconceptions in research interpretations and clinical implications, with serious disorders being overlooked or misdiagnosed. Careful research has now identified sex differences in the cardiovascular, renal, endocrine, gastrointestinal, immune, nervous, and musculoskeletal systems. Also, several cardiovascular, immunological, and neurological disorders have shown differences in prevalence and severity between males and females. Genetic variations in the sex chromosomes have been implicated in several disorders at young age and before puberty. The levels of the gonadal hormones estrogen, progesterone and testosterone and their receptors play a role in the sex differences between adult males and premenopausal women. Hormonal deficiencies and cell senescence have been implicated in differences between postmenopausal and premenopausal women. Specifically, cardiovascular disorders are more common in adult men vs premenopausal women, but the trend is reversed with age with the incidence being greater in postmenopausal women than age-matched men. Gender-specific disorders in females such as polycystic ovary syndrome, hypertension-in-pregnancy and gestational diabetes have attained further research recognition. Other gender-related research areas include menopausal hormone therapy, the "Estrogen Paradox" in pulmonary arterial hypertension being more predominant but less severe in young females, and how testosterone may cause deleterious effects in the kidney while having vasodilator effects in the coronary circulation. This has prompted the National Institutes of Health (NIH) initiative to consider sex as a biological variable in research. The NIH and other funding agencies have provided resources to establish state-of-the-art centers for women health and sex differences in biology and disease in several academic institutions. Scientific societies and journals have taken similar steps to organize specialized conferences and publish special issues on gender-based research. These combined efforts should promote research to enhance our understanding of the sex differences in biological systems beyond just the reproductive system, and provide better guidance and pharmacological tools for the management of various clinical disorders in a gender-specific manner.

The association of hysterectomy with or without ovarian conservation with subclinical atherosclerosis progression in healthy postmenopausal women

OBJECTIVE

While the deleterious associations of surgical menopause after bilateral oophorectomy with cardiovascular disease are documented, less is specifically known concerning subclinical atherosclerosis progression.

METHODS

We used data from 590 healthy postmenopausal women randomized to hormone therapy or placebo in the Early versus Late Intervention Trial with Estradiol (ELITE), which was conducted from July 2005 to February 2013. Subclinical atherosclerosis progression was measured as annual rate of change in carotid artery intima-media thickness (CIMT) over a median 4.8 years. Mixed-effects linear models assessed the association of hysterectomy and bilateral oophorectomy compared with natural menopause with CIMT progression adjusted for age and treatment assignment. We also tested modifying associations by age at or years since oophorectomy or hysterectomy.

RESULTS

Among 590 postmenopausal women, 79 (13.4%) underwent hysterectomy with bilateral oophorectomy and 35 (5.9%) underwent hysterectomy with ovarian conservation, a median of 14.3 years before trial randomization. Compared with natural menopause, women who underwent hysterectomy with and without bilateral oophorectomy had higher fasting plasma triglycerides while women who underwent bilateral oophorectomy had lower plasma testosterone. The CIMT progression rate in bilaterally oophorectomized women was 2.2 μm/y greater than natural menopause ( P = 0.08); specifically, compared with natural menopause, the associations were significantly greater in postmenopausal women who were older than 50 years at the time of bilateral oophorectomy ( P = 0.014) and in postmenopausal women who underwent bilateral oophorectomy more than 15 years before randomization ( P = 0.015). Moreover, the CIMT progression rate in hysterectomized women with ovarian conservation was 4.6 μm/y greater than natural menopause ( P = 0.015); in particular, compared with natural menopause, the association was significantly greater in postmenopausal women who underwent hysterectomy with ovarian conservation more than 15 years before randomization ( P = 0.018).

CONCLUSIONS

Hysterectomy with bilateral oophorectomy and ovarian conservation were associated with greater subclinical atherosclerosis progression relative to natural menopause. The associations were stronger for later age and longer time since oophorectomy/hysterectomy. Further research should continue to examine long-term atherosclerosis outcomes related to oophorectomy/hysterectomy.

Focusing on testosterone levels in male: A half-longitudinal study of polycyclic aromatic hydrocarbon exposure and diastolic blood pressure in coke oven workers

Polycyclic aromatic hydrocarbons (PAHs) can interfere with testosterone levels, and low levels of testosterone are associated with increased cardiovascular events. To explore the role of testosterone in PAHs exposure and cardiovascular health, we used data from the 2011-2016 National Health and Nutrition Examination Survey (NHANES) and a longitudinal database of 332 male coke oven workers from China. The urine PAHs, tobacco metabolites and plasma testosterone levels of coke oven workers were measured. There were inverse associations between serum (plasma) testosterone concentrations and the risk of dysarteriotony and dyslipidemia among the NHANES participants and coke oven workers. The results of the cross-lagged panel analysis among workers showed that the decrease in testosterone preceded the increase in diastolic blood pressure (DBP), and the absolute value of the path coefficient from baseline testosterone to follow-up DBP (β₂ = -8.162, P = 0.077) was significantly larger than the absolute value of the path coefficient from baseline DBP to follow-up testosterone (β₁ = -0.001, P = 0.781). Results from the half-longitudinal mediation analysis showed that baseline hydroxyfluorene predicted significant decreases in plasma testosterone from baseline to follow-up (path a: 0.71, 95% CI: 1.26, -0.16), whereas plasma testosterone at baseline also predicted significant increments in DBP from baseline to follow-up (path b: 9.22, 95% CI: 17.24, -1.19). The indirect effect of PAHs on DBP via plasma testosterone level was marginally significant (test for indirect effects a*b (P = 0.08)). In conclusion, testosterone level is a longitudinal precursor to increased DBP and plays an essential role in the association between PAHs exposure and damage to the cardiovascular system. Coke oven workers with low plasma testosterone levels are more likely to experience adverse changes in blood pressure and lipid levels after exposure to PAHs.

Examining the Role of Physical Activity Interventions in Modulating Androgens and Cardiovascular Health in Postmenopausal Women: A Narrative Review

A growing body of literature has examined the role of physical activity (PA) in modifying the effects of estrogen withdrawal on cardiovascular health in postmenopausal women, but the impact of PA on androgens is less clear. Changes in androgen concentrations following regular PA may improve cardiovascular health. This narrative review summarizes the literature assessing the impact of PA interventions on androgens in postmenopausal women. The association between changes in androgen concentrations and cardiovascular health following PA programs is also examined. Randomized controlled trials were included if they (i) implemented a PA program of any type and duration in postmenopausal women and (ii) measured changes in androgen concentrations. Following PA interventions, no changes in androstenedione, conflicting changes in dehydroepiandrosterone/dehydroepiandrosterone-sulfate, and increases in sex hormone-binding globulin concentrations were found. Total testosterone decreased following aerobic PA but increased after resistance training. Most aerobic PA interventions led to reductions in free testosterone. A combination of caloric restriction and/or fat loss enhanced the influence of PA on most androgens. Evidence exploring the relationship between changes in androgens and cardiovascular health indicators was scarce and inconsistent. PA has shown promise in modifying the concentrations of some androgens (free and total testosterone, sex hormone-binding globulin), and remains a well-known beneficial adjuvant option for postmenopausal women to manage their cardiovascular health. Fat loss influences the effect of PA on androgens, but the synergistic role of PA and androgens on cardiovascular health merits further examination. Many research gaps remain regarding the relationship between PA, androgens, and cardiovascular disease in postmenopausal women.

Revisiting the physiological role of androgens in women

INTRODUCTION

Extensive research underlines the critical functions of androgens in females. Nevertheless, the precise mechanisms of their action are poorly understood. Here, we review the existing literature regarding the physiological role of androgens in women throughout life.

AREAS COVERED

Several studies show that androgen receptors (ARs) are broadly expressed in numerous female tissues. They are essential for many physiological processes, including reproductive, sexual, cardiovascular, bone, muscle, and brain health. They are also involved in adipose tissue and liver function. Androgen levels change with the menstrual cycle and decrease in the first decades of life, independently of menopause.

EXPERT OPINION

To date, studies are limited by including small numbers of women, the difficulty of dosing androgens, and their cyclical variations. In particular, whether androgens play any significant role in regulating the establishment of pregnancy is poorly understood. The neural functions of ARs have also been investigated less thoroughly, although it is expressed at high levels in brain structures. Moreover, the mechanism underlying the decline of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) with age is unclear. Other factors, including estrogen's effect on adrenal androgen production, reciprocal regulation of ARs, and non-classical effects of androgens, remain to be determined.

Sex hormones and physical function among the Chinese oldest-old and centenarian women

Background

Physical independence is crucial for overall health in the elderly individuals. The life expectancy of women has been shown to be higher than that of men, which is also known as the “male–female health-survival paradox”. Sex hormones may be one of the explanations. However, the relationships between sex hormones and physical function remain unclear in the elderly females. This study was designed to explore these relationships among the Chinese oldest-old and centenarian women.

Methods

Data from 1226 women were obtained from the China Hainan Centenarian Cohort Study. Home interviews, physical examinations and blood analyses were conducted using standardized procedures. Variables including age, Han ethnicity, illiteracy, smoker, drinker, estradiol (E2), testosterone (T), follicle-stimulating hormone, and luteinizing hormone were used in the multivariate logistic and linear regression analyses.

Results

In all the participants, age [beta (95% confidence interval): − 0.84 (− 0.98, − 0.71)] and E2 levels [beta (95% confidence interval): − 0.22 (− 0.28, − 0.17)] were negatively associated with activities of daily living (ADLs) in the multivariate linear regression analyses (P < 0.05 for all). We also observed significantly negative associations of age [odds ratio (95% confidence interval): 0.90 (0.88, 0.91)] and E2 levels [odds ratio (95% confidence interval): 0.98 (0.98, 0.99)] with physical normality in the multivariate logistic regression analyses (P < 0.05 for all). Age and E2 levels gradually decreased with increases in the ADL quartiles across all the participants (P < 0.05 for all).

Conclusions

This study demonstrated that E2 levels were negatively associated with physical function among the Chinese oldest-old and centenarian women.

Associations between blood sex steroid concentrations and risk of major adverse cardiovascular events in healthy older women in Australia: a prospective cohort substudy of the ASPREE trial

BACKGROUND

Blood testosterone concentrations in women decline during the reproductive years and reach a nadir in the seventh decade, after which concentrations increase and are restored to those of reproductive-aged women early in the eighth decade. We aimed to establish the association between the concentration of testosterone in the blood and risk of major adverse cardiovascular events (MACE) and all-cause mortality in healthy older women.

METHODS

SHOW was a prospective cohort substudy of the longitudinal randomised ASPREE trial. Eligible participants were women aged at least 70 years from Australia with unimpaired cognition, no previous MACE, and a life expectancy of at least 5 years. Participants who were receiving hormonal or steroid therapy were ineligible for inclusion. We measured serum concentrations of sex steroids with liquid chromatography-tandem mass spectrometry and of SHBG with immunoassay. We compared lower concentrations of sex hormones with higher concentrations using four quartiles. Primary endpoints were risk of MACE and all-cause mortality, the associations of which with sex steroid concentrations were assessed using Cox proportional hazards regression that included age, body-mass index, smoking status, alcohol consumption, diabetes, hypertension, dyslipidaemia, impaired renal function, and treatment allocation in the ASPREE trial (aspirin vs placebo). ASPREE is registered with ClinicalTrials.gov, NCT01038583.

FINDINGS

Of the 9180 women recruited to the ASPREE trial between March 10, 2010, and Dec 31 2014, 6358 participants provided sufficient biobank samples at baseline and 5535 were included in the final analysis. Median age at entry was 74·0 years (IQR 71·7-77·7). During a median 4·4 years of follow-up (24 553 person-years), 144 (2·6%) women had a first MACE (incidence 5·9 per 1000 person-years). During a median 4·6 years of follow-up (3·8-5·6), 200 women died (7·9 per 1000 person-years). In the fully adjusted models, higher concentrations of testosterone were associated with a lower incidence of MACE (quartile 4 vs quartile 1: hazard ratio 0·57 [95% CI 0·36-0·91]; p=0·02), as were higher concentrations of DHEA (quartile 4 vs quartile 1: 0·61 [0·38-0·97]; p=0·04). For oestrone, a lower risk of MACE was seen for concentrations in quartile 2 only, compared with quartile 1 (0·55 [0·33-0·92]; p=0·02). In fully adjusted models, no association was seen between SHBG and MACE, or between any hormone or SHBG and all-cause mortality.

INTERPRETATION

Blood concentrations of testosterone and DHEA above the lowest quartile in older women were associated with a reduced risk of a first-ever MACE. Given that the physiological effects of DHEA are mediated through its steroid metabolites, if the current findings were to be replicated, trials investigating testosterone therapy for the primary prevention of ischaemic cardiovascular disease events in older women would be warranted.

FUNDING

The National Health and Medical Research Council of Australia, US National Institute on Aging, the Victorian Cancer Agency, the Commonwealth Scientific and Industrial Research Organisation, and Monash University.

Androgen therapy for women after menopause

Androgens are essential hormones in women. Yet, androgen therapy is understudied and underutilized despite showing improvement in postmenopausal hypoactive sexual desire disorder (HSDD) and the genitourinary syndrome of menopause (GSM). Additionally, regulatory concerns have left a significant gap in commercially available testosterone preparations, formulated specifically for women, in most countries. This has led to off-label use of male formulations and compounded therapies which are under-regulated. Beyond HSDD and GSM, testosterone likely influences the brain, breast, cardiovascular and musculoskeletal systems. These effects are not well studied, and therefore it is difficult to counsel patients on testosterone therapy when used for these endpoints. Ultimately, further study is needed to elucidate these effects, create a fuller picture of the risks and benefits, and encourage product development specifically designed for women.

Testosterone attenuates hypoxia-induced hypertension by affecting NRF1-mediated transcriptional regulation of ET-1 and ACE

Hypertension induced by hypoxia at high altitude is one of the typical symptoms of high-altitude reactions (HARs). Emerging evidence indicates that endothelial abnormalities, including increases in angiotensin-2 (Ang-2) and endothelin-1 (ET-1), are closely associated with hypertension. Thus, low blood oxygen-induced endothelial dysfunction through acceleration of Ang-2 and ET-1 synthesis may alleviate HARs. In this study, we investigated the effects of hypoxia on rat blood pressure (BP) and endothelial injury. We found that BP increased by 10 mmHg after treatment with 10% O₂ (~5500 m above sea level) for 24 h. Consistently, serum Ang-2 and ET-1 levels were increased along with decreases in NO levels. In endothelial cells, angiotensin-1-converting enzyme (ACE) and ET-1 expression levels were upregulated. Interestingly, nuclear respiratory factor 1 (NRF1) levels were also upregulated, consistent with the changes in ACE and ET-1 levels. We further demonstrated that NRF1 transcriptionally activated ACE and ET-1 by directly binding to their promoter regions, suggesting that the endothelial cell dysfunction induced by hypoxia was due to NRF1-dependent upregulation of ACE and ET-1. Surprisingly, testosterone supplementation showed significant protective effects on BP, while castration induced even higher BPs in rats exposed to hypoxia. We further showed that physiological testosterone repressed NRF1 expression in vivo and in vitro and thereby reduced Ang-2 and ET-1 levels, which was dependent on hypoxia. In summary, we have identified that physiological testosterone protects against hypoxia-induced hypertension through inhibition of NRF1, which transcriptionally regulates ACE and ET-1 expression.

Use of Testosterone in Postmenopausal Women

The role of testosterone in women and its potential as a therapeutic agent continue to attract controversy. The clinical trials of testosterone therapy for women primarily have focused on treatment of female sexual dysfunction, with the largest placebo-controlled studies being of transdermal testosterone in postmenopausal women. Based on the cumulative data from these studies, loss of sexual desire with associated personal distress currently is the only agreed-on indication for judicious testosterone supplementation for postmenopausal women. This article reviews the physiology of testosterone in women, summarizes the findings from observational studies and clinical trials, and considers indications for testosterone use.

Longitudinal changes over three years in sex steroid hormone levels in women aged 70 years and over

OBJECTIVE

Sex steroid levels in women vary with increasing age from the age of 70 years (70+). Whether this reflects change within individuals with age or a survival advantage is not known. This study aimed to determine the stability of circulating sex steroids and SHBG over time in individual women aged 70+.

DESIGN

A prospective cohort study.

PARTICIPANTS

400 women, aged 70+ not using any sex steroid, anti-androgen/oestrogen or glucocorticoid therapy.

MAIN OUTCOME MEASUREMENTS

Sex steroid concentrations, measured by liquid chromatography-tandem mass spectrometry and sex hormone-binding globulin (SHBG) by immunoassay, in paired blood samples drawn 3 years apart and analysed together.

RESULTS

400 women, median (IQR) age 78.0 (8.6) years, were included in the analysis. Mean testosterone concentrations were statistically significantly higher in follow-up samples compared with baseline. The change was modest (mean change 31 pmol/L, 95% confidence interval (CI) 2.4-59.8; p = .034), and an increase was not observed in all women. There was a statistically significant decline in mean body mass index (mean change -0.4 kg/m² , 95% CI 0.6 to -0.3; p < .001) and a significant increase in the mean serum SHBG concentration (mean change 4.0 nmol/L, 95% CI 2.7-5.4; p < .001). The change observed in testosterone was not explained by the observed change in SHBG. There was no significant change in the mean oestrone or dehydroepiandrosterone concentration.

CONCLUSIONS

Testosterone concentrations in women aged 70+ were more likely to increase than decrease. Whether increasing testosterone concentrations in older women confer a survival advantage needs investigation.

Sex differences in vascular aging in response to testosterone

Large elastic arterial stiffening and endothelial dysfunction are phenotypic characteristics of vascular aging, a major risk factor for age-associated cardiovascular diseases. Compared to men, vascular aging in women appears to be slowed until menopause, whereafter vascular aging accelerates to match that seen in men. These sex differences in vascular aging have been attributed to changes in sex hormones that occur with aging. Although the role of estradiol in vascular aging in women has been highlighted in recent aging research, little is known about the impact of declining testosterone concentrations in both sexes. Importantly, while androgen concentrations generally decline with age in men, there are data that indicate reductions in androgen concentrations in women as well. Evidence suggests that low testosterone is associated with impaired endothelial function and increased arterial stiffness in men, although the effect of androgens on vascular aging in women remains unclear. Testosterone may modulate vascular aging by mitigating the effects of oxidative stress and inflammation, although there is sex specificity to this effect. The purpose of this review is to present and summarize the research regarding sex differences in vascular aging in response to androgens, specifically testosterone. Because exercise is a potent lifestyle factor for slowing and reversing vascular aging, we briefly summarize the available literature regarding the regulatory function of testosterone on vascular adaptations to exercise training.

11-Oxygenated C19 Steroids Do Not Decline With Age in Women

CONTEXT

The ovaries and adrenals are sources of androgens in women. Although dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), and testosterone (T) all decline with age, these C19 steroids correlate poorly with parameters of androgen action in postmenopausal women.

OBJECTIVE

To comprehensively compare the androgen profiles of pre- and postmenopausal women.

METHODS

We quantified 19 steroids-including DHEA; DHEAS; T; androstenedione (A4); and the following adrenal-specific 11-oxygenated C19 steroids (11oxyandrogens): 11β-hydroxytestosterone (11OHT), 11-ketotestosterone (11KT), 11β-hydroxyandrostenedione (11OHA4), and 11-ketoandrostenedione (11KA4)-using liquid chromatography-tandem mass spectrometry in morning serum obtained from 100 premenopausal (age 20 to 40 years) and 100 postmenopausal (age ≥ 60 years) women. Double immunofluorescence of 3β-hydroxysteroid dehydrogenase type 2 (HSD3B2) with cytochrome b5 (CYB5A) or sulfotransferase 2A1 (SULT2A1) was performed in normal adrenal glands obtained from eight premenopausal and eight postmenopausal women.

RESULTS

DHEA, DHEAS, A4, and T were significantly higher in pre- than in postmenopausal women (2.9, 2.8, 2.9, and 1.6-fold, respectively; P < 0.0001). In contrast, the 11-oxyandrogens did not decrease with aging, and the 11OHT/T and 11OHA4/A4 ratios showed strong positive correlations with age (r = 0.5 and 0.8, respectively; P < 0.0001). Double immunofluorescence analysis showed that with the involution of the zona reticularis in the old adrenals, the sharp zonal segregation of HSD3B2 and CYB5A becomes less distinct, and areas of HSD3B2 and CYB5A overlap are observed.

CONCLUSIONS

Unlike DHEA, DHEAS, A4, and T, the 11oxyandrogens do not decline in aging women. Structural changes within the adrenal cortex might explain the evolution of androgen profiles in aging women.

Sex differences in endothelial function important to vascular health and overall cardiovascular disease risk across the lifespan

Diseases of the cardiovascular system are the leading cause of morbidity and mortality in men and women in developed countries, and cardiovascular disease (CVD) is becoming more prevalent in developing countries. The prevalence of atherosclerotic CVD in men is greater than in women until menopause, when the prevalence of CVD increases in women until it exceeds that of men. Endothelial function is a barometer of vascular health and a predictor of atherosclerosis that may provide insights into sex differences in CVD as well as how and why the CVD risk drastically changes with menopause. Studies of sex differences in endothelial function are conflicting, with some studies showing earlier decrements in endothelial function in men compared with women, whereas others show similar age-related declines between the sexes. Because the increase in CVD risk coincides with menopause, it is generally thought that female hormones, estrogens in particular, are cardioprotective. Moreover, it is often proposed that androgens are detrimental. In truth, the relationships are more complex. This review first addresses female and male sex hormones and their receptors and how these interact with the cardiovascular system, particularly the endothelium, in healthy young women and men. Second, we address sex differences in sex steroid receptor-independent mechanisms controlling endothelial function, focusing on vascular endothelin and the renin-angiotensin systems, in healthy young women and men. Finally, we discuss sex differences in age-associated endothelial dysfunction, focusing on the role of attenuated circulating sex hormones in these effects.

Intersection between gonadal function and vascular aging in women

Vascular aging, characterized by endothelial dysfunction and large elastic arterial stiffening, is a major risk factor for age-associated cardiovascular disease (CVD). Although women have a lower prevalence of CVD until midlife, prevalence rates increase rapidly coincident with the menopausal transition to match those observed in men. The menopausal transition, or perimenopause, is a chaotic period that is associated with increased symptoms (e.g., hot flashes, depressed mood, anxiety, sleep disturbances) and CVD risk factors due to changes in the hormonal environment. Because these quality of life factors and CVD risk factors also change with aging, the arteries of women appear to endure a double insult. Our laboratory has been investigating how changes in gonadal function and hormone levels with the menopause transition impacts the vascular aging process in healthy women. Our work has shown that vascular endothelial function progressively declines, and large elastic arterial stiffness is greater across the stages of the menopausal transition. This acceleration in vascular aging may be due to the loss of vasodilatory, antioxidant, anti-inflammatory, and antiproliferative effects of estradiol on the vascular wall. This minireview discusses the impact of changes in gonadal function and hormones with the menopausal transition on vascular aging in women and areas for investigations to further our understanding of the intersection between gonadal function and vascular aging.

Intravaginal Testosterone Improves Sexual Satisfaction and Vaginal Symptoms Associated With Aromatase Inhibitors

CONTEXT

Intravaginal testosterone (IVT) is a potential treatment of vulvovaginal atrophy (VVA) associated with aromatase inhibitor (AI) use.

OBJECTIVE

To investigate the effects of IVT on sexual satisfaction, vaginal symptoms, and urinary incontinence (UI) associated with AI use.

DESIGN

Double-blind, randomized, placebo-controlled trial.

SETTING

Academic clinical research center.

PARTICIPANTS

Postmenopausal women taking an AI with VVA symptoms.

INTERVENTION

IVT cream (300 μg per dose) or identical placebo, self-administered daily for 2 weeks and then thrice weekly for 24 weeks.

MAIN OUTCOMES AND MEASURES

The primary outcome was the change in the sexual satisfaction score on the Female Sexual Function Index (FSFI). Secondary outcomes included vaginal symptoms and responses to the Profile of Female Sexual Function, the Female Sexual Distress Scale-Revised (FSDS-R), and the Questionnaire for UI Diagnosis. Serum sex steroids were measured.

RESULTS

A total of 44 women were randomly assigned and 37 provided evaluable data, (mean age 56.4 years, SD 8.8 years). At 26 weeks, the mean between-group difference in the baseline-adjusted change in FSFI satisfaction scores was significantly greater for the IVT group than the placebo group (mean difference 0.73 units; 95% CI, 0.02 to 1.43; P = 0.043). IVT cream resulted in significant improvements, compared with placebo, in FSDS-R scores (P = 0.02), sexual concerns (P < 0.001), sexual responsiveness (P < 0.001), vaginal dryness (P = 0.009), and dyspareunia (P = 0.014). Serum sex steroid levels did not change. Few women had UI symptoms, with no treatment effect.

CONCLUSION

IVT significantly improved sexual satisfaction and reduced dyspareunia in postmenopausal women on AI therapy. The low reporting of UI among women on AI therapy merits further investigation.

Androgens in postmenopausal women: a review

There is significant interest in the use of androgen therapy for postmenopausal women. This review provides background on endogenous androgens in women, describes factors that affect circulating androgen concentrations, and examines the relationship between low levels of androgens and sexual problems. Possible effects of androgens in postmenopausal women beyond sexual function also are discussed. Clinical trials of androgen therapy for the treatment of hypoactive sexual desire disorder are reviewed, with a discussion of potential risks. A practical approach to using androgens to treat low sexual desire with associated distress is presented, accompanied by an illustrative case.

Androgens and cardiovascular disease in women and men

Cardiovascular disease is the leading cause of death in both women and men. Its pathogenesis is multifactorial, with sex hormones playing an important role. Androgens have both direct and indirect effects on the vasculature. This review summarizes evidence on the association of both endogenous and exogenous androgens with subclinical and overt cardiovascular disease in women and men. Concerning women, both high and low levels of endogenous androgens have been associated with cardiovascular disease, while other studies have reported no association. Adiposity, impaired glucose metabolism, dyslipidemia and estrogen levels may mediate the observed associations. Regarding testosterone therapy in women, there have been no large prospective studies on cardiovascular outcomes. Concerning men, most studies indicate that low levels of circulating testosterone are associated with increased rates of cardiovascular disease in the general population; the causality, however, of this association remains to be proven. Testosterone replacement therapy in men with symptoms of hypogonadism and low serum testosterone merits caution with regard to cardiovascular safety, as evidence is still conflicting.

Ischemic preconditioning: Interruption of various disorders

Ischemic heart diseases are the leading cause of morbidity and mortality worldwide. Reperfusion of an ischemic heart is necessary to regain the normal functioning of the heart. However, abrupt reperfusion of an ischemic heart elicits a cascade of adverse events that leads to injury of the myocardium, i.e., ischemia-reperfusion injury. An endogenous powerful strategy to protect the ischemic heart is ischemic preconditioning, in which the myocardium is subjected to short periods of sublethal ischemia and reperfusion before the prolonged ischemic insult. However, it should be noted that the cardioprotective effect of preconditioning is attenuated in some pathological conditions. The aim of this article is to review present knowledge on how menopause and some metabolic disorders such as diabetes and hyperlipidemia affect myocardial ischemic preconditioning and the mechanisms involved.

Endothelial maintenance in health and disease: Importance of sex differences

The vascular endothelium has emerged as more than just an inert monolayer of cells lining the vascular bed. It represents the interface between the blood stream and vessel wall, and has a strategic role in regulating vascular homeostasis by the release of vasoactive substances. Endothelial dysfunction contributes to the development and progression of cardiovascular disease. Recognition of sex-specific factors implicated in endothelial cell biology is important for the identification of clinically relevant preventive and/or therapeutic strategies. This review aims to give an overview of the recent advances in understanding the importance of sex specific observations in endothelial maintenance, both in healthy and diseased conditions. The female endothelium is highlighted in the context of polycystic ovary syndrome and pre-eclampsia. Furthermore, sex differences are explored in chronic kidney disease, which is currently appreciated as one of public health priorities. Overall, this review endorses integration of sex analysis in experimental and patient-oriented research in the exciting field of vascular biology.

Endothelial dysfunction and vascular disease - a 30th anniversary update

The endothelium can evoke relaxations of the underlying vascular smooth muscle, by releasing vasodilator substances. The best-characterized endothelium-derived relaxing factor (EDRF) is nitric oxide (NO) which activates soluble guanylyl cyclase in the vascular smooth muscle cells, with the production of cyclic guanosine monophosphate (cGMP) initiating relaxation. The endothelial cells also evoke hyperpolarization of the cell membrane of vascular smooth muscle (endothelium-dependent hyperpolarizations, EDH-mediated responses). As regards the latter, hydrogen peroxide (H₂ O₂ ) now appears to play a dominant role. Endothelium-dependent relaxations involve both pertussis toxin-sensitive G_i (e.g. responses to α₂ -adrenergic agonists, serotonin, and thrombin) and pertussis toxin-insensitive G_q (e.g. adenosine diphosphate and bradykinin) coupling proteins. New stimulators (e.g. insulin, adiponectin) of the release of EDRFs have emerged. In recent years, evidence has also accumulated, confirming that the release of NO by the endothelial cell can chronically be upregulated (e.g. by oestrogens, exercise and dietary factors) and downregulated (e.g. oxidative stress, smoking, pollution and oxidized low-density lipoproteins) and that it is reduced with ageing and in the course of vascular disease (e.g. diabetes and hypertension). Arteries covered with regenerated endothelium (e.g. following angioplasty) selectively lose the pertussis toxin-sensitive pathway for NO release which favours vasospasm, thrombosis, penetration of macrophages, cellular growth and the inflammatory reaction leading to atherosclerosis. In addition to the release of NO (and EDH, in particular those due to H₂ O₂ ), endothelial cells also can evoke contraction of the underlying vascular smooth muscle cells by releasing endothelium-derived contracting factors. Recent evidence confirms that most endothelium-dependent acute increases in contractile force are due to the formation of vasoconstrictor prostanoids (endoperoxides and prostacyclin) which activate TP receptors of the vascular smooth muscle cells and that prostacyclin plays a key role in such responses. Endothelium-dependent contractions are exacerbated when the production of nitric oxide is impaired (e.g. by oxidative stress, ageing, spontaneous hypertension and diabetes). They contribute to the blunting of endothelium-dependent vasodilatations in aged subjects and essential hypertensive and diabetic patients. In addition, recent data confirm that the release of endothelin-1 can contribute to endothelial dysfunction and that the peptide appears to be an important contributor to vascular dysfunction. Finally, it has become clear that nitric oxide itself, under certain conditions (e.g. hypoxia), can cause biased activation of soluble guanylyl cyclase leading to the production of cyclic inosine monophosphate (cIMP) rather than cGMP and hence causes contraction rather than relaxation of the underlying vascular smooth muscle.

Androgens modulate male-derived endothelial cell homeostasis using androgen receptor-dependent and receptor-independent mechanisms

BACKGROUND

Sex-related differences in the role of androgen have been reported in cardiovascular diseases and angiogenesis. Moreover, androgen receptor (AR) has been causally involved in the homeostasis of human prostate endothelial cells. However, levels of expression, functionality and biological role of AR in male- and female-derived human endothelial cells (ECs) remain poorly characterized. The objectives of this work were (1) to characterize the functional expression of AR in male- and female-derived human umbilical vein endothelial cell (HUVEC), and (2) to specifically analyze the biological effects of DHT, and the role of AR on these effects, in male-derived HUVECs (mHUVECs).

RESULTS

Immunohistochemical analyses of tissue microarrays from benign human tissues confirmed expression of AR in ECs from several androgen-regulated and non-androgen-regulated human organs. Functional expression of AR was validated in vitro in male- and female-derived HUVECs using quantitative RT-PCR, immunoblotting and AR-mediated transcriptional activity assays. Our results indicated that functional expression of AR in male- and female-derived HUVECs was heterogeneous, but not sex dependent. In parallel, we analyzed in depth the biological effects of DHT, and the role of AR on these effects, on proliferation, survival and tube formation capacity in mHUVECs. Our results indicated that DHT did not affect mHUVEC survival; however, DHT stimulated mHUVEC proliferation and suppressed mHUVEC tube formation capacity. While the effect of DHT on proliferation was mediated through AR, the effect of DHT on tube formation did not depend on the presence of a functional AR, but rather depended on the ability of mHUVECs to further metabolize DHT.

CONCLUSIONS

(1) Heterogeneous expression of AR in male- and female-derived HUVEC could define the presence of functionally different subpopulations of ECs that may be affected differentially by androgens, which could explain, at least in part, the pleiotropic effects of androgen on vascular biology, and (2) DHT, and metabolites of DHT, generally thought to represent progressively more hydrophilic products along the path to elimination, may have differential roles in modulating the biology of human ECs through AR-dependent and AR-independent mechanisms, respectively.

Association of free testosterone and sex hormone binding globulin with metabolic syndrome and subclinical atherosclerosis but not blood pressure in hypertensive perimenopausal women

INTRODUCTION

Data on the role of androgens as potential mediators of increasing cardiovascular risk in women at midlife are controversial. The aim of the study was to analyze the relationship of free testosterone (FT) and sex hormone binding globulin (SHBG) with blood pressure and subclinical organ damage and metabolic syndrome (MS) in middle aged hypertensive women.

MATERIAL AND METHODS

One hundred and fifty-two women with newly diagnosed arterial hypertension were included in the study. In all subjects blood pressure measurements were performed as well as echocardiographic examination with left ventricular structure and function assessment (GE Vivid 7.0), carotid ultrasound with measurement of intima-media thickness (IMT), and carotid-femoral pulse wave velocity (PWV) measurement (Sphygmocor). A fasting blood sample was taken to measure glucose and lipid concentrations. Serum testosterone and SHBG were measured. Free testosterone was calculated according to the Vermeulen formula. Metabolic syndrome was defined following the International Diabetes Federation (IDF) recommendations.

RESULTS

Free testosterone was significantly higher and SHBG lower in women with MS independently of menopausal status. The odds ratio of MS per quartile increment in FT after adjustment for covariates was 2.06 (95% CI: 1.16-3.65). There was no correlation between FT, SHBG and blood pressure. Free testosterone was associated with decreased left ventricular diastolic function (E/A ratio β = -0.19, p = 0.05) and subclinical atherosclerosis (IMT β = 0.34, p = 0.009), but not arterial stiffness.

CONCLUSIONS

Free testosterone and SHBG independently of menopause status are related to MS. Free testosterone is associated with worse metabolic profile, subclinical atherosclerosis and impaired diastolic function of the left ventricle.

Analysis of the Relationship between Estradiol and Follicle-Stimulating Hormone Concentrations and Polymorphisms of Apolipoprotein E and LeptinGenes in Women Post-Menopause

Background: Menopause is the permanent cessation of menstruation due to loss of ovarian follicular activity. A review of the available literature indicates that correlations between the changes that take place in a woman’s body after menopause and different genetic variants are still being sought. Methods: The study was conducted in 252 women who had completed physiological menopause. The women were divided into groups according to the time elapsed since menopause. The total concentrations of estradiol and follicle-stimulating hormone were determined by means of electrochemiluminescence. The apolipoprotein E (APOE) and lepitn (LEP) genotypes were determined by real-time PCR and polymerase chain reaction–restriction fragment length polymorphism, respectively. Results: We observed that people with the APOE3/E3 genotype entered menopause insignificantly later compared to other genotypes. Additionally, in the group of patients with the APOE3/E3 genotypes, differences in the E2 concentration were significantly related to the time since their last menstruation. There is no association found in the literature between these polymorphisms of the LEP gene and hormones. Conclusions: To date, attempts to formulate a model describing the association between E2 and FSH concentration with the polymorphisms of various genes of menopause in women have not been successful. This relationship is difficult to study because of the number of nongenetic factors. Environmental factors can explain variation in postmenopausal changes in hormone levels.

Low testosterone levels are associated with endothelial dysfunction in oophorectomized early postmenopausal women

BACKGROUND

The actual consequences of low testosterone levels in women remain uncertain.

OBJECTIVE

To assess endogenous testosterone influence on body composition, vascular and metabolic function in recent postmenopausal women.

DESIGN

We studied 81 postmenopausal women under transdermal estradiol (E2) replacement therapy, 36 with bilateral oophorectomy (group O), and 45 controls (group C) through venous occlusion plethysmography, bioimpedance, DEXA, biochemical, hormonal, and inflammatory profile.

RESULTS

Total testosterone level (TT) in group O was 11.0 (4.0-17.75) vs 23.0 (10.0-42.5) ng/dl in group C (P=0.001). Forearm blood flow, in ml/min/100  ml tissue, was lower in group O compared to group C at baseline (1.57 (1.05-2.47) vs 2.19 (1.59-2.66) P=0.036), following reactive hyperemia response (endothelium-dependent flow mediated dilatation, 3.44 (2.38-4.35) vs 4.3 (3.09-5.52), P=0.031) and following nitroglycerin (endothelium-independent dilation, 1.39 (0.99-1.7) vs 1.76 (1.15-2.0), P=0.025), with a positive correlation between TT and all parameters except for the reactive hyperemia response (r=0.233-0.312, P=0.036-0.004). The sVCAM1 levels were negatively correlated with TT (r=-0.320, P=0.005). E2 and other hormone levels, biochemical parameters and body composition did not differ between groups. Multiple linear regressions showed that the levels of TT, compared with other confounding variables, may explain the variation observed on endothelial parameters, with low explanatory power.

CONCLUSION

The absence of ovarian testosterone production in recent postmenopausal oophorectomized women was associated with deleterious effects on endothelial function.

Testosterone in women--the clinical significance

Testosterone is an essential hormone for women, with physiological actions mediated directly or via aromatisation to oestradiol throughout the body. Despite the crucial role of testosterone and the high circulating concentrations of this hormone relative to oestradiol in women, studies of its action and the effects of testosterone deficiency and replacement in women are scarce. The primary indication for the prescription of testosterone for women is loss of sexual desire, which causes affected women substantial concern. That no formulation has been approved for this purpose has not impeded the widespread use of testosterone by women--either off-label or as compounded therapy. Observational studies indicate that testosterone has favourable cardiovascular effects measured by surrogate outcomes; however, associations between endogenous testosterone and the risk of cardiovascular disease and total mortality, particularly in older women, are yet to be established. Adverse cardiovascular effects have not been seen in studies of transdermal testosterone therapy in women. Clinical trials suggest that exogenous testosterone enhances cognitive performance and improves musculoskeletal health in postmenopausal women. Unmet needs include the availability of approved testosterone formulations for women and studies to elucidate the contribution of testosterone to cardiovascular, cognitive, and musculoskeletal health and the risk of cancer.

Effects of testosterone on visuospatial function and verbal fluency in postmenopausal women: results from a functional magnetic resonance imaging pilot study

OBJECTIVE

This study aims to investigate the effects of testosterone on cognitive performance during functional magnetic resonance imaging (fMRI) in healthy estrogen-treated postmenopausal women.

METHODS

This was an open-label study in which postmenopausal women on nonoral estrogen therapy were treated with transdermal testosterone for 26 weeks. Women performed tests of verbal fluency (number of words) and mental rotation (reaction time and accuracy) during pretreatment and posttreatment fMRI. Blood oxygen level-dependent (BOLD) signal intensity was measured during fMRI tasks.

RESULTS

Nine women with a mean (SD) age of 55.4 (3.8) years completed the study. Twenty-six weeks of testosterone therapy was associated with significant decreases in BOLD intensity during the mental rotation task in the right superior parietal, left inferior parietal, and left precuneus regions, and during the verbal fluency task in the left inferior frontal gyrus, left lingual gyrus, and medial frontal gyrus (all P < 0.05), with no change in task performance, accuracy, or speed.

CONCLUSIONS

Testosterone therapy is associated with reduced BOLD signal activation in key anatomical areas during fMRI verbal fluency and visuospatial tasks in healthy estrogen-treated postmenopausal women. Our interpretation is that testosterone therapy facilitates preservation of cognitive function with less neuronal recruitment.

Transdermal testosterone improves verbal learning and memory in postmenopausal women not on oestrogen therapy

OBJECTIVE

The aim of this study was to examine the effects of testosterone on verbal learning and memory in postmenopausal women.

DESIGN

Randomized, placebo-controlled trial in which participants were randomized (1:1) to transdermal testosterone gel 300 mcg/day, or identical placebo, for 26 weeks.

PATIENTS

Ninety-two postmenopausal women aged 55-65 years, on no systemic sex hormone therapy.

MEASUREMENTS

The primary outcome was the score for the International Shopping List Task (ISLT) of CogState. Secondary outcomes included other CogState domains, the Psychological General Well-Being Index (PGWB) and safety variables.

RESULTS

Eighty-nine women, median age 60 years, were included in the primary analysis. Testosterone treatment resulted in statistically significantly better performance for the ISLT (improved verbal learning and memory) compared with placebo, adjusted for age and baseline score (mean difference 1·57; 95%CI 0·13, 3·01) P = 0·03). There were no significant differences for other CogState domains or the PGWB scores. At 26 weeks, the median total testosterone was 1·7 nm (interquartile range (IQR) 1·1, 2·4) in the testosterone group and 0·4 nm (IQR 0·3, 0·5) in the placebo group.

CONCLUSIONS

The small but statistically significant effect of testosterone treatment on verbal learning and memory in postmenopausal women provides the basis for further clinical trials.

The role of hormones and aromatase inhibitors on breast tumor growth and general health in a postmenopausal mouse model

BACKGROUND

Breast cancer is the most frequently diagnosed cancer in women in the United States. Approximately 70% of breast cancers are diagnosed in postmenopausal women. Major clinical trials and experimental studies showed that aromatase inhibitors are effective against postmenopausal breast cancer. Despite their effectiveness in reducing tumor recurrence, aromatase inhibitors have adverse effects on the cardiovascular system and increase osteoporosis and bone fractures. Our study is aimed at investigating the role of natural steroid hormones on serum cardiovascular and bone resorption markers in an established mouse model mimicking postmenopausal breast cancer.

METHODS

Ovariectomized nude mice were transplanted with MCF-7 breast cancer cells constitutively expressing aromatase. The mice were treated with different combinations and doses of steroids, [estrogen (25 pg, 40 pg, 100 pg), progesterone (6 ng) and testosterone (50 ng)] along with dehydroepiandrostenedione (100 ug). Serum levels of HDL, LDL/VLDL, free and total cholesterol, total and bone specific alkaline phosphatase and triglycerides were analyzed after 5, 10 and 15 months.

RESULTS

Free cholesterol and LDL/VLDL levels in serum were reduced in groups mimicking estrous cycle and menstrual cycle hormones treatment. HDL cholesterol was increased in all the hormone treated groups except the estrous cycle-mimicking group. Bone specific alkaline phosphatase was decreased in menstrual cycle levels of estrogen and progesterone treatment.

CONCLUSIONS

All together our results show that use of natural hormones in appropriate combinations have beneficial effects on cardiac and bone toxicity, along with better tumor reduction than current treatments.

The Effect of Testosterone on Cardiovascular Disease

Cardiovascular disease is the leading cause of death in the United States. Testosterone is the principal male sex hormone and plays an important role in men’s health and well-being. Historically, testosterone was believed to adversely affect cardiovascular function. However, contemporary literature has refuted this traditional thinking; testosterone has been suggested to have a protective effect on cardiovascular function through its effects on the vascular system. Data from modern research indicate that hypogonadism is closely related to the development of various cardiovascular risk factors, including hyperlipidemia and insulin resistance. Several studies have demonstrated beneficial effects of testosterone supplementation therapy on reversing symptoms of hypogonadism and improving cardiovascular disease risk profiles. In this review, we perform a critical analysis on the association between testosterone and cardiovascular disease.

Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease

Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD.

Testosterone protects female embryonic heart H9c2 cells against severe metabolic stress by activating estrogen receptors and up-regulating IES SUR2B

A recent clinical study demonstrated that a testosterone supplementation improves functional capacity in elderly female patients suffering from heart failure. These findings prompted us to consider possible mechanisms of testosterone-induced cardioprotection in females. To address this question we have used a pure female population of rat heart embryonic H9c2 cells. Pre-treatment of cells with testosterone for 24h significantly increased survival of H9c2 cells exposed to 2,4-dinitrophenol (DNP), an inhibitor of oxidative phosphorylation. These cells expressed low level of androgen receptors and the effect of testosterone was not modified by hydroxyflutamide, an antagonist of androgen receptor. In contrast, cyclohexamide, an inhibitor of protein biosynthesis, and tamoxifene, a partial agonist of estrogen receptors, abolished cardioprotection afforded by testosterone. In addition, finasteride, an inhibitor of 5α-reductase, and anastrazole, an inhibitor of α-aromatase, also blocked testosterone-induced cytoprotection. Real time RT-PCR revealed that testosterone did not regulate the expression of nine subunits and accessory proteins of sarcolemmal ATP-sensitive K(+) (K(ATP)) channels. On the other hand, testosterone, as well as 17β-estradiol, up-regulated a putative mitochondrial K(ATP) channel subunit, mitochondrial sulfonylurea receptor 2B intraexonics splice variant (IES SUR2B), without affecting expression of IES SUR2A. Tamoxifene inhibited testosterone-induced up-regulation of IES SUR2B without affecting IES SUR2A. In conclusion, this study has shown that testosterone protect female embryonic heart H9c2 cells against severe metabolic stress by its conversion into metabolites that activate estrogen receptors and up-regulate IES SUR2B.

Androgens for postmenopausal women's health?

Obesity, metabolic syndrome, and diabetes are becoming a leading health concern in the developed Countries, due to their link to cardiovascular disease. These conditions are common in women in the post-menopausal period. Unfortunately, actual lifestyle change strategy fail to prevent cardiovascular events for several reasons, thus specific medications are needed. In addition, it was showed an increased cardiovascular diseases and breast cancer risk in postmenopausal women taking estrogens alone or with progestin, thus the optimal therapy for the prevention of chronic disease in women is still lacking. Androgens exert different actions on organs like adipose tissue, brain, bone, and on cardiovascular system. However, a debate still exists on the positive role of androgens on human health, especially in women. Furthermore, the vascular effects of androgens remain poorly understood and have been controversial for a long time. Sex hormones are important determinants of body composition. Aging is, often, accompanied by a decrease in free testosterone levels, a concomitant reduction in muscle mass and an increase in fat mass. Furthermore, numerous studies showed that total serum testosterone levels were inversely related to the atherosclerosis disease incidence in postmenopausal women. New therapeutic targets may, therefore, arise understanding how androgen could influence the fat distribution, the metabolic disease onset, the vascular reactivity and cardiovascular risk, in both sex.

Testosterone and heart failure

Testosterone deficiency is a generalized phenomenon seen in the course of chronic heart failure (CHF). Reduction in circulating testosterone level is a predictor of deterioration of functional capacity over time, underscoring the role of testosterone deficiency in CHF. Anabolic hormones are determinants of exercise capacity and circulating levels of anabolic hormones strongly determine muscle mass and strength. Testosterone deficiency is involved in the pathophysiology of CHF, contributing to some features of this syndrome, such as the reduced muscle mass, abnormal energy handling, fatigue, dyspnea and, finally, cachexia. This review summarizes current knowledge on the role of testosterone deficiency in the pathophysiology of CHF, gaining insights from the potential implications of testosterone as supplementation therapy.

Testosterone enhances estradiol's cardioprotection in ovariectomized rats

After menopause, the development of cardiovascular disease (CVD) is due not only to estrogen decline but also to androgen decline. This study examined the effects of either estradiol (E(2)) or testosterone replacement alone or E(2)-testosterone combination on isolated myocytes in ovariectomized (Ovx) rats subjected to ischemia/reperfusion (I/R). Furthermore, we determined whether the effects are associated with β(2)-adrenoceptor (β(2)-AR). Five groups of adult female Sprague-Dawley rats were used: Sham operation (Sham) rats, bilateral Ovx rats, Ovx rats with E(2) 40 μg/kg per day (Ovx+E), Ovx rats with testosterone 150 μg/kg per day (Ovx+T), and Ovx rats with E(2) 40 μg/kg per day+testosterone 150 μg/kg per day (Ovx+E/T). We determined the lactate dehydrogenase (LDH) release, percentage of rod-shaped cells and apoptosis of ventricular myocytes from rats of all groups subjected to I/R. Then, we determined the above indices and contractile function with or without a selective β(2)-AR antagonist ICI 118 551. We also determined the expression of β(2)-AR. Our data show that either E(2) or testosterone replacement alone or E(2) and testosterone in combination decreased the LDH release, increased the percentage of rod-shaped cells, reduced apoptotic cells (%), and combination treatment appeared to be more effective than either E(2) or testosterone replacement alone. ICI 118 551 abolished the effects of the three. Combination supplementation also enhanced the expression of β(2)-AR. We concluded that in Ovx rats, testosterone enhances E(2)'s cardioprotection, while E(2) and testosterone in combination was more effective and the protective effects may be associated with β(2)-AR. The study highlights the potential therapeutic application for CVD in postmenopausal women.