Role of endogenous androgens on carotid atherosclerosis in non-obese postmenopausal women

Metabolic benefits afforded by estradiol and testosterone in both sexes: clinical considerations

Testosterone (T) and 17β-estradiol (E2) are produced in male and female humans and are potent metabolic regulators in both sexes. When E2 and T production stops or decreases during aging, metabolic dysfunction develops and promotes degenerative metabolic and vascular disease. Here, we discuss the shared benefits afforded by E2 and T for metabolic function human females and males. In females, E2 is central to bone and vascular health, subcutaneous adipose tissue distribution, skeletal muscle insulin sensitivity, antiinflammatory immune function, and mitochondrial health. However, T also plays a role in female skeletal, vascular, and metabolic health. In males, T's conversion to E2 is fundamental to bone and vascular health, as well as prevention of excess visceral adiposity and the promotion of insulin sensitivity via activation of the estrogen receptors. However, T and its metabolite dihydrotestosterone also prevent excess visceral adiposity and promote skeletal muscle growth and insulin sensitivity via activation of the androgen receptor. In conclusion, T and E2 are produced in both sexes at sex-specific concentrations and provide similar and potent metabolic benefits. Optimizing levels of both hormones may be beneficial to protect patients from cardiometabolic disease and frailty during aging, which requires further study.

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.

Yeast Hydrolysate and Postmenopausal Osteoporosis

We used an ovariectomy (OVX) rat model to test whether yeast hydrolysate (YH) has therapeutic effects on postmenopausal osteoporosis-induced bone loss. The rats were separated into five treatment groups: the sham group (sham operation); the control group (no treatment after OVX); the estrogen group (estrogen treatment after OVX); YH 0.5% group (drinking water supplementation with 0.5% YH after OVX); and the YH 1% group (drinking water supplementation with 1% YH after OVX). In addition, the YH treatment restored serum testosterone concentration in the OVX rats up to the normal level. Further, YH treatment affected bone markers; a significant increase in serum calcium concentration was observed after adding YH to the diet. The levels of serum alkaline phosphatase, osteocalcin, and cross-linked telopeptides of type I collagen were reduced by YH supplementation, unlike those in the no-treatment control. Although not statistically significant, YH treatment in OVX rats improved trabecular bone microarchitecture parameters. These results show that YH may ameliorate the bone loss caused by postmenopausal osteoporosis because of the normalization of serum testosterone concentration.

17β-Estradiol Inhibits Proliferation and Oxidative Stress in Vascular Smooth Muscle Cells by Upregulating BHLHE40 Expression

Background: Intimal hyperplasia is a major complication of restenosis after angioplasty. The abnormal proliferation and oxidative stress of vascular smooth muscle cells (VSMCs) are the basic pathological feature of neointimal hyperplasia. 17β-Estradiol can inhibit VSMCs proliferation and inflammation. However, it is still unclear whether and how 17β-Estradiol affects intimal hyperplasia.

Methods: The neointima hyperplasia was observed by hematoxylin/eosin staining. The expression of PCNA, cyclin D1, NOX1, NOX4 and p47^phox in neointima hyperplasia tissues and VSMCs was determined by qRT-PCR and Western blotting. MTS assay, cell counting and EdU staining were performed to detect cells proliferation. The oxidative stress was assessed by ROS staining.

Results: 17β-Estradiol suppressed carotid artery ligation-induced intimal hyperplasia, which is accompanied by an increase of BHLHE40 level. Furthermore, loss- and gain-of-function experiments revealed that BHLHE40 knockdown promotes, whereas BHLHE40 overexpression inhibits TNF-α-induced VSMC proliferation and oxidative stress. 17β-Estradiol inhibited TNF-α-induced VSMC proliferation and oxidative stress by promoting BHLHE40 expression, thereby suppressing MAPK signaling pathways. In addition, enforcing the expression of BHLHE40 leads to amelioration of intimal hyperplasia.

Conclusions: Our study demonstrates that 17β-Estradiol inhibits proliferation and oxidative stress in vivo and in vitro by promotion of BHLHE40 expression.

Differences in association of lower bone mineral density with higher coronary calcification in female and male end-stage renal disease patients

Background

Risk of cardiac events and cardiovascular disease (CVD) in end-stage renal disease (ESRD) patients are predicted by coronary artery calcification (CAC) independently. It is not clear to what extent low bone mineral density (BMD) is associated with higher risk of CAC and if sex interacts. We investigated the sex-specific associations of CAC score with total body BMD (tBMD) as well as with BMD of different skeletal sub-regions.

Methods

In 174 ESRD patients, median age 57 (10th–90th percentiles 29–75) years, 63% males, BMD (measured by dual-energy X-ray absorptiometry; DXA), CAC score (measured by cardiac CT) and circulating inflammatory biomarkers were analysed.

Results

A total of 104 (60%) patients with CAC > 100 AUs were older, had higher prevalence of both clinical CVD and diabetes, higher level of high sensitivity C-reactive protein, tumour necrosis factor, interleukin-6 and lower T-score of tBMD. Female patients had significantly lower tBMD and BMD of all skeletal sub-regions, except head, than male patients. Female patients with high CAC (> 100 AUs) had significantly decreased T-score of tBMD, and lower BMD of arms, legs than those low CAC (≤ 100 AUs); elevated CAC score were associated with tBMD, T-score, Z-score of tBMD and BMD of arms and legs, while no such differences was observed in males. Multivariate generalized linear model (GLM) analysis adjusted for age, diabetes and hsCRP showed that in females per SD higher CAC score (1057 AUs) was predicted by either per SD (0.13 g/cm²) lower tBMD or per SD (0.17 g/cm²) lower BMD at legs. No such associations were found in male ESRD patients.

Conclusions

In female, but not male, lower BMD, in particular sub-regions of legs, was associated with higher CAC score independently. Low BMD has the potential to identify increased risk for high CAC score in ESRD patients.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1235-z) contains supplementary material, which is available to authorized users.

Polycystic ovary syndrome and the risk of cardiometabolic complications in longitudinal studies

The purpose of this study was to perform a review of the longitudinal studies to determine whether polycystic ovary syndrome is associated with higher prevalence of metabolic complications and cardiovascular morbidity and mortality. The primary outcomes included body mass index, metabolic syndrome and its components (waist circumference, lipid profile, arterial hypertension, abnormal glucose metabolism (impaired fasting glucose, impaired glucose tolerance, type 2 diabetes), insulin resistance, and cardiovascular diseases like stroke, angina, and coronary heart disease. Complications in pregnant women were beyond the scope of this review. PubMed database (1992-2018) was searched to identify proper publications. Finally, data from 47 articles were analysed. Studies differed in the design (prospective, retrospective, cohort, observational), research methods, polycystic ovary syndrome diagnostic criteria, studied populations, race, and ethnicity of the participants. Based on the data collected, it appears that women with polycystic ovary syndrome have higher prevalence of obesity, abdominal fat distribution, dyslipidaemia and deterioration of glucose metabolism, but increased prevalence of cardiovascular diseases is not proven.

Rationale and design of a cohort study on primary ovarian insufficiency in female survivors of Hodgkin's lymphoma: influence on long-term adverse effects (SOPHIA)

INTRODUCTION

Hodgkin's lymphoma (HL) has become the prototype of a curable disease. However, many young survivors suffer from late adverse effects of treatment. Both chemotherapy (CT) and radiotherapy (RT) may induce primary ovarian insufficiency (POI), which has been associated with reduced bone mineral density (BMD), neurocognitive dysfunction and possibly cardiovascular disease (CVD). While the general assumption is that POI increases CVD risk, other hypotheses postulate reverse causality, suggesting that cardiovascular risk factors determine menopausal age or that biological ageing underlies both POI and CVD risk. None of these hypotheses are supported by convincing evidence. Furthermore, most studies on POI-associated conditions have been conducted in women with early natural or surgery-induced menopause with short follow-up times. In this study, we will examine the long-term effects of CT-induced and/or RT-induced POI on BMD, cardiovascular status, neurocognitive function and quality of life in female HL survivors.

METHODS AND ANALYSIS

This study will be performed within an existing Dutch cohort of HL survivors. Eligible women were treated for HL at ages 15-39 years in three large hospitals since 1965 and survived for ≥8 years after their diagnosis. Women visiting a survivorship care outpatient clinic will be invited for a neurocognitive, cardiovascular and BMD assessment, and asked to complete several questionnaires and to provide a blood sample. Using multivariable regression analyses, we will compare the outcomes of HL survivors who developed POI with those who did not. Cardiovascular status will also be compared with women with natural POI.

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board of the Netherlands Cancer Institute and has been registered at 'Toetsingonline' from the Dutch Central Committee on Research involving Human Subjects (file no. NL44714.031.13). Results will be disseminated through peer-reviewed publications and will be incorporated in follow-up guidelines for HL survivors.

Cardiovascular RiskprofilE - IMaging and gender-specific disOrders (CREw-IMAGO): rationale and design of a multicenter cohort study

Background

Reproductive disorders, such as polycystic ovary syndrome (PCOS), primary ovarian insufficiency (POI) and hypertensive pregnancy disorders (HPD) like pre-eclampsia (PE), are associated with an increased risk of cardiovascular disease (CVD). Detection of early signs of cardiovascular disease (CVD), as well as identification of risk factors among women of reproductive age which improve cardiovascular risk prediction, is a challenge and current models might underestimate long-term health risks. The aim of this study is to assess cardiovascular disease in patients with a history of a reproductive disorder by low-dose computed tomography (CT).

Methods

Women of 45 - 55 years, who experienced a reproductive disorder (PCOS, POI, HPD), are invited to participate in this multicenter, prospective, cohort study. Women will be recruited after regular cardiovascular screening, including assessment of classical cardiovascular risk factors. CT of the coronary arteries (both coronary artery calcium scoring (CACS), and contrast-enhanced coronary CT angiography (CCTA)) and carotid siphon calcium scoring (CSC) is planned in 300 women with HPD and 300 women with PCOS or POI. In addition, arterial stiffness (non-invasive pulse wave velocity (PWV)) measurement and cell-based biomarkers (inflammatory circulating cells) will be obtained.

Discussion

Initial inclusion is focused on women of 45 - 55 years. However, the age range (40 - 45 years and/or ≥ 55 years) and group composition may be adjusted based on the findings of the interim analysis. Participants can potentially benefit from information obtained in this study concerning their current cardiovascular health and expected future risk of cardiovascular events. The results of this study will provide insights in the development of CVD in women with a history of reproductive disorders. Ultimately, this study may lead to improved cardiovascular prediction models and will provide an opportunity for timely adjustment of preventive strategies. Limitations of this study include the possibility of overdiagnosis and the average radiation dose of 3.5 mSv during coronary and carotid siphon CT, although the increased lifetime malignancy risk is negligible.

Trial registration

Netherlands Trial Register, NTR5531. Date registered: October 21st, 2015.

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.

The androgen receptor confers protection against diet-induced atherosclerosis, obesity, and dyslipidemia in female mice

Androgens have important cardiometabolic actions in males, but their metabolic role in females is unclear. To determine the physiologic androgen receptor (AR)–dependent actions of androgens on atherogenesis in female mice, we generated female AR-knockout (ARKO) mice on an atherosclerosis-prone apolipoprotein E (apoE)–deficient background. After 8 weeks on a high-fat diet, but not on a normal chow diet, atherosclerosis in aorta was increased in ARKO females (+59% vs. control apoE-deficient mice with intact AR gene). They also displayed increased body weight (+18%), body fat percentage (+62%), and hepatic triglyceride levels, reduced insulin sensitivity, and a marked atherogenic dyslipidemia (serum cholesterol, +52%). Differences in atherosclerosis, body weight, and lipid levels between ARKO and control mice were abolished in mice that were ovariectomized before puberty, consistent with a protective action of ovarian androgens mediated via the AR. Furthermore, the AR agonist dihydrotestosterone reduced atherosclerosis (−41%; thoracic aorta), subcutaneous fat mass (−44%), and cholesterol levels (−35%) in ovariectomized mice, reduced hepatocyte lipid accumulation in hepatoma cells in vitro, and regulated mRNA expression of hepatic genes pivotal for lipid homeostasis. In conclusion, we demonstrate that the AR protects against diet-induced atherosclerosis in female mice and propose that this is mediated by modulation of body composition and lipid metabolism.—Fagman, J. B., Wilhelmson, A. S., Motta, B. M., Pirazzi, C., Alexanderson, C., De Gendt, K., Verhoeven, G., Holmäng, A., Anesten, F., Jansson, J.-O., Levin, M., Borén, J., Ohlsson, C., Krettek, A., Romeo, S., Tivesten, A. The androgen receptor confers protection against diet-induced atherosclerosis, obesity, and dyslipidemia in female mice.

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.

Androgen replacement therapy in women

Female androgens are derived from either the adrenal and peripheral conversion of the adrenal sex steroid precursor, dehydroepiandrosterone, or from direct ovarian production. Adrenal insufficiency or bilateral oophorectomy (surgical menopause) result in severe androgen deficiency, which can be clinically associated with impaired libido, drive and energy. Physiological menopause does not necessarily lead to androgen deficiency. The previously suggested definition of female androgen deficiency syndrome, as the concurrent presence of low androgen levels and low libido, is not precise enough and may lead to overdiagnosis. Current replacement options include transdermal testosterone or oral dehydroepiandrosterone treatment, both of which have been shown to result in significant improvements, in particular in libido and mood, while long-term effects on body composition, cardiovascular and cancer risk are less documented. Owing to these concerns, androgen replacement should be reserved for women with severe androgen deficiency due to an established cause and matching clinical symptoms.

Effect modification of obesity on associations between endogenous steroid sex hormones and arterial calcification in women at midlife

OBJECTIVE

The aim of this study was to examine whether obesity modifies the effects of endogenous steroid sex hormones on arterial calcification in women at midlife.

METHODS

Associations between estradiol, testosterone, sex hormone-binding globulin, and free androgen index and the presence and extent of coronary and aortic calcification were evaluated in 187 obese (body mass index, ≥30 kg/m) and 281 nonobese (body mass index, <30 kg/m) women from the Study of Women's Health Across the Nation. Logistic and linear regressions were used as appropriate.

RESULTS

Prevalence rates of coronary and aortic calcification were significantly higher among obese compared with nonobese women (P < 0.001, for both). In multivariable analyses, steroid sex hormones were not associated with the presence of coronary calcification. However, for the extent of coronary calcification, significant interactions were found between obesity and both sex hormone-binding globulin (P < 0.0001) and free androgen index (P = 0.008). In nonobese women, higher sex hormone-binding globulin (P = 0.0006) and lower free androgen index (P = 0.01) were associated with a greater extent of coronary calcification, whereas lower sex hormone-binding globulin was associated with greater extent of coronary calcification in obese women (P = 0.05). For aortic calcification outcomes, higher sex hormone-binding globulin was associated with the presence of aortic calcification among nonobese women (odds ratio, 1.64; 95% CI, 1.16-2.32, for each 1-SD greater sex hormone-binding globulin).

CONCLUSIONS

Associations between endogenous steroid sex hormones and arterial calcification vary by obesity status among perimenopausal women. Further research is needed to better understand the possible mechanisms of these associations.

Cardiovascular risk in postmenopausal women with the polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the commonest endocrine disorders, affecting 5-10% of the female population of reproductive age. "Classic" PCOS is characterized by clinical or biochemical hyperandrogenism and oligo-ovulation. According to the 2003 Rotterdam criteria, two additional phenotypes are recognized: (1) the ovulatory patient with androgen excess and polycystic ovarian morphology and (2) the anovulatory patient with polycystic ovarian morphology without androgen excess. PCOS is associated with an adverse cardiometabolic profile, consisting of increased total or central adiposity, increased blood pressure, a pro-atherogenic lipid profile, increased inflammatory markers, insulin resistance and abnormal glucose metabolism. Furthermore, the incidence of overt or gestational diabetes mellitus, as well as of preeclampsia is significantly higher in PCOS patients. Among the various PCOS phenotypes, those with evidence of androgen excess have the highest burden of cardiovascular risk. Studies evaluating the incidence of cardiovascular disease in postmenopausal women with PCOS are extremely sparse. The available data so far indicate that coronary heart disease, as well as cerebrovascular disease is more common in postmenopausal PCOS patients. Persisting high androgen levels through the menopause, obesity and maturity onset diabetes mellitus are proposed as the main mechanisms accounting for the increased risk.

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.

The effects of endogenous and exogenous androgens on cardiovascular disease risk factors and progression

Cardiovascular disease incidence rates have long been known to significantly differ between the two sexes. Estrogens alone fail to explain this phenomenon, bringing an increasing amount of attention to the role of androgens. Contrary to what was initially hypothesized, androgens seem to have an overall cardioprotective effect, especially in men. Recent studies and published data continue to support this notion displaying a consistent inverse correlation with atherosclerosis progression and cardiovascular disease both in regressive and prospective study models. Clinical studies have also revealed what seems to be a differential androgenic effect on various cardiovascular risk factors between men and women. Further insight indicates that in order to avoid confusion it may be also preferable to separately examine the effects of endogenous androgen levels from exogenous testosterone administration, as well as discern the differential results of low to normal and supraphysiological administration doses. This review summarizes old and recent data according to the above distinctions, in an attempt to further our understanding of the role of androgens in cardiovascular disease.