Evidence for an association between dehydroepiandrosterone sulfate and nonfatal, premature myocardial infarction in males

Modifiable and Non-Modifiable Risk Factors for Premature Coronary Heart Disease (PCHD): Systematic Review and Meta-Analysis

AIM

We aimed to compare the prevalence of modifiable and non-modifiable coronary heart disease (CHD) risk factors among those with premature CHD and healthy individuals.

METHODS

PubMed, CINAHL, Embase, and Web of Science databases were searched (review protocol is registered in PROSPERO CRD42020173216). The quality of studies was assessed using the National Heart, Lung and Blood Institute tool for cross-sectional, cohort and case-control studies. Meta-analyses were performed using Review Manager 5.3. Effect sizes for categorical and continuous variables, odds ratio (OR) and mean differences (MD)/standardised mean differences (SMD) with 95% confidence intervals (CI) were reported.

RESULTS

A total of n=208 primary studies were included in this review. Individuals presenting with premature CHD (PCHD, age ≤65 years) had higher mean body mass index (MD 0.54 kg/m2, 95% CI 0.24, 0.83), total cholesterol (SMD 0.27, 95% CI 0.17, 0.38), triglycerides (SMD 0.50, 95% CI 0.41, 0.60) and lower high-density lipoprotein cholesterol (SMD 0.79, 95% CI: -0.91, -0.68) compared with healthy individuals. Individuals presenting with PCHD were more likely to be smokers (OR 2.88, 95% CI 2.51, 3.31), consumed excessive alcohol (OR 1.40, 95% CI 1.05, 1.86), had higher mean lipoprotein (a) levels (SMD 0.41, 95% CI 0.28, 0.54), and had a positive family history of CHD (OR 3.65, 95% CI 2.87, 4.66) compared with healthy individuals. Also, they were more likely to be obese (OR 1.59, 95% CI 1.32, 1.91), and to have had dyslipidaemia (OR 2.74, 95% CI 2.18, 3.45), hypertension (OR 2.80, 95% CI 2.28, 3.45), and type 2 diabetes mellitus (OR 2.93, 95% CI 2.50, 3.45) compared with healthy individuals.

CONCLUSION

This meta-analysis confirms current knowledge of risk factors for PCHD, and identifying these early may reduce CHD in young adults.

Alterations in gut microbiota and urine metabolomics in infants with yin-deficiency constitution aged 0–2 years

Background

Based on the constitution theroy, infants are classified into balanced constitution (BC) and unbalanced constitution. Yin-deficiency constitution (YINDC) is a common type of unbalanced constitutions in Chinese infants. An infant's gut microbiota directly affects the child's health and has long-term effects on the maturation of the immune and endocrine systems throughout life. However, the gut microbiota of infants with YINDC remains unknown. Herein, we aimed to evaluate the intestinal flora profiles and urinary metabolites in infant with YINDC, find biomarkers to identify YINDC, and promote our understanding of infant constitution classification.

Methods

Constitutional Medicine Questionnaires were used to assess the infants' constitution types. 47 infants with 21 cases of YINDC and 26 cases of BC were included, and a cross-sectional sampling of stool and urine was conducted. Fecal microbiota was characterized using 16S rRNA sequencing, and urinary metabolomics was profiled using UPLC-Q-TOF/MS method. YINDC markers with high accuracy were identified using receiver operating characteristic (ROC) analysis.

Results

The diversity and composition of intestinal flora and urinary metabolites differed significantly between the YINDC and BC groups. A total of 13 obviously different genera and 55 altered metabolites were identified. Stool microbiome shifts were associated with urine metabolite changes. A combined marker comprising two genera may have a high potential to identify YINDC with an AUC of 0.845.

Conclusions

Infants with YINDC had a unique gut microbiota and metabolomic profile resulting in a constitutional microclassification. The altered gut microbiome in YINDC may account for the higher risk of cardiovascular diseases. Metabolomic analysis of urine showed that metabolic pathways, including histidine metabolism, proximal tubule bicarbonate reclamation, arginine biosynthesis, and steroid hormone biosynthesis, were altered in infants with YINDC. Additionally, the combined bacterial biomarker had the ability to identify YINDC. Identifying YINDC in infancy and intervening at an early stage is crucial for preventing cardiovascular diseases.

Hormonal and Metabolic Changes of Aging and the Influence of Lifestyle Modifications

Increased life expectancy combined with the aging baby boomer generation has resulted in an unprecedented global expansion of the elderly population. The growing population of older adults and increased rate of age-related chronic illness has caused a substantial socioeconomic burden. The gradual and progressive age-related decline in hormone production and action has a detrimental impact on human health by increasing risk for chronic disease and reducing life span. This article reviews the age-related decline in hormone production, as well as age-related biochemical and body composition changes that reduce the bioavailability and actions of some hormones. The impact of hormonal changes on various chronic conditions including frailty, diabetes, cardiovascular disease, and dementia are also discussed. Hormone replacement therapy has been attempted in many clinical trials to reverse and/or prevent the hormonal decline in aging to combat the progression of age-related diseases. Unfortunately, hormone replacement therapy is not a panacea, as it often results in various adverse events that outweigh its potential health benefits. Therefore, except in some specific individual cases, hormone replacement is not recommended. Rather, positive lifestyle modifications such as regular aerobic and resistance exercise programs and/or healthy calorically restricted diet can favorably affect endocrine and metabolic functions and act as countermeasures to various age-related diseases. We provide a critical review of the available data and offer recommendations that hopefully will form the groundwork for physicians/scientists to develop and optimize new endocrine-targeted therapies and lifestyle modifications that can better address age-related decline in heath.

Prognostic Value of Dehydroepiandrosterone Sulfate for Patients With Cardiovascular Disease: A Systematic Review and Meta-Analysis

BACKGROUND

The aim of the present study was to estimate the impact of dehydroepiandrosterone sulfate (DHEAS) on the prognosis of patients with cardiovascular disease by performing a systematic review and meta-analysis.

METHODS AND RESULTS

The Embase, PubMed, Web of Science, CNKI, and WanFang databases were searched up to September 5, 2016, to identify eligible studies. The quality of each study was assessed using the Newcastle-Ottawa Scale. The association between DHEAS, either on admission or at discharge, and cardiovascular disease outcomes were reviewed. The overall risk ratio for the effect of DHEAS on all-cause mortality and fatal and nonfatal cardiovascular events was pooled using a fixed-effects or a random-effects model. The publication bias was evaluated using funnel plots. Twenty-five studies were included for systematic review. The follow-up duration ranged from 1 to 19 years. Eighteen studies were included in the meta-analysis. We found that lower DHEAS levels indicated a significant increased risk for all-cause mortality (risk ratio, 1.47; 95% CI, 1.38-1.56 [P<0.00001]), fatal cardiovascular event (risk ratio, 1.58; 95% CI, 1.30-1.91 [P<0.00001]), and nonfatal cardiovascular event (risk ratio, 1.42; 95% CI, 1.24-1.62 [P<0.0001]) in patients with cardiovascular disease.

CONCLUSIONS

Patients with cardiovascular disease who have lower DHEAS levels may have poorer prognosis than those with higher DHEAS levels.

Serum androgen concentrations and subclinical measures of cardiovascular disease in men and women

OBJECTIVES

Most of the observed associations of androgens and sex hormone-binding globulin (SHBG) with subclinical cardiovascular disease (CVD) stem from selected study samples with immunoassay-based hormone measurements. Thus, we used a large population-based sample with total testosterone (TT) and androstenedione (ASD) concentrations measured by liquid chromatography-tandem mass spectrometry.

DESIGN

Data of 2140 individuals (mean age: 60,8 years) from the cohort Study of Health in Pomerania were assessed at baseline and 5-year follow-up.

METHODS

Multivariable regression models were implemented to assess cross-sectional and longitudinal associations of TT, free testosterone (fT), ASD, SHBG and dehydroepiandrosterone-sulphate (DHEAS) with measures of subclinical CVD including intima media thickness (IMT), carotid plaques, left ventricular mass (LVM), fractional shortening (FS), relative wall thickness (RWT), and left ventricular geometry.

RESULTS

Cross-sectional analyses yielded an association of TT with IMT in women (β-coefficient per log unit increase: 0.02; 95% CI: 0.007; 0.45) and ASD with FS in both sexes (men: β-coefficient: -2.94; 95% CI: -4.75; -1.12; women: β-coefficient: 1.64; 95% CI: 0.55; 2.73). In longitudinal analyses, DHEAS was positively associated with FS change (β-coefficient: 2.34; 95% CI: -0.59; 4.08). In women, SHBG was positively associated with incident plaques (Q1 vs. Q3 (Ref.): β-coefficient: 1.35; 95% CI: 1.04; 1.74). In both sexes, longitudinal analyses showed no consistent association of TT with subclinical CVD.

CONCLUSIONS

Despite several sex-specific associations of androgens and SHBG with subclinical CVD, the present representative study for the age group ≥45 years among men and women from the general population detected no consistent associations in longitudinal analyses.

Dehydroepiandrosterone sulfate as a risk factor for premature myocardial infarction: a comparative study

Background

This study aimed to evaluate some of the major risk factors of myocardial infarction including dehydroepiandrosterone sulfate in patients with premature myocardial infarction (age <50 years old) and myocardial infarction (age ≥50 years).

Methods

This is a parallel case-control study on 50 premature myocardial infarction patients and 50 myocardial infarction patients. We also recruited 50 matched participants for each of the two groups. Patients and their control groups were assessed for dehydroepiandrosterone sulfate serum level, diabetes mellitus, hyperlipidemia, hypertriglyceridemia, and hypertension. In addition, family history of cardiovascular disease and current smoking was recorded. Univariate and multivariate logistic regression analyses were performed to evaluate predictors of premature myocardial infarction and myocardial infarction.

Results

No significant differences were observed between the demographic data of patients and their controls. The dehydroepiandrosterone sulfate serum level was significantly higher in patients with premature myocardial infarction compared with controls. Multivariate logistic regression analysis revealed only serum dehydroepiandrosterone sulfate dehydroepiandrosterone sulfate level to be significantly associated with premature myocardial infarction (odds ratio, 2.65; 95% confidence interval, 1.44 to 4.877; P = 0.002). Additionally, hypertension was found to be associated with myocardial infarction.

Conclusion

Higher levels of serum dehydroepiandrosterone sulfate level are associated with premature myocardial infarction but not with myocardial infarction, and this association is independent of the effects of other risk factors.

DHEA prevents mineralo- and glucocorticoid receptor-induced chronotropic and hypertrophic actions in isolated rat cardiomyocytes

Corticosteroids have been involved in the genesis of ventricular arrhythmias associated with pathological heart hypertrophy, although molecular mechanisms responsible for these effects have not been completely explained. Because mineralocorticoid receptor (MR) antagonists have been demonstrated to be beneficial on the cardiac function, much attention has been given to the action of aldosterone on the heart. However, we have previously shown that both aldosterone and corticosterone in vitro induce a marked acceleration of the spontaneous contractions, as well as a significant cell hypertrophy in isolated neonate rat ventricular cardiomyocytes. Moreover, a beneficial role of the steroid hormone dehydroepiandrosterone (DHEA) has been also proposed, but the mechanism of its putative cardioprotective function is not known. We found that DHEA reduces both the chronotropic and the hypertrophic responses of cardiomyocytes upon stimulation of MR and glucocorticoid receptor (GR) in vitro. DHEA inhibitory effects were accompanied by a decrease of T-type calcium channel expression and activity, as assessed by quantitative PCR and the patch-clamp technique. Prevention of cell hypertrophy by DHEA was also revealed by measuring the expression of A-type natriuretic peptide and BNP. The kinetics of the negative chronotropic effect of DHEA, and its sensitivity to actinomycin D, pointed out the presence of both genomic and nongenomic mechanisms of action. Although the genomic action of DHEA was effective mostly upon MR activation, its rapid, nongenomic response appeared related to DHEA antioxidant properties. On the whole, these results suggest new mechanisms for a putative cardioprotective role of DHEA in corticosteroid-associated heart diseases.

SULT2A1 Gene Copy Number Variation is Associated with Urinary Excretion Rate of Steroid Sulfates

Human cytosolic sulfotransferases (SULT) 2A1 is the main enzyme involved in the sulfate conjugation of dehydroepiandrosterone, a weak androgen, and the main androgen precursor, whereas estrogens are mainly conjugated by SULT1A1. Here we have identified a copy number variation (CNV) polymorphism in the SULT2A1 gene in a Swedish population including healthy men (N = 30). Moreover, the CNV of SULT1A1 and SULT2A1 was further characterized in relation to urinary levels of androgen sulfate metabolites before and after an intramuscular dose of 500 mg testosterone enanthate. Individuals expressing two or more CNVs excrete 80 and 40% higher levels of DHEAS (p = 0.02) and androsteroneS (p = 0.01), respectively as compared to individuals with one gene copy. The mean area under the urine concentration time-curve from time 0 (prior to the administration of 500 mg testosterone) to 15 days post dose values were 80% higher for DHEAS (p = 0.046) and testosteroneS (p = 0.019) in individuals with two and three SULT2A1 gene copies as compared to individuals with one gene copy. The SULT1A1 CNV on the other hand did not affect the sulfation activity toward the androgens. In conclusion our results indicate that functional CNV polymorphisms in SULT2A1 and SULT1A1 are common in a Swedish population and that SULT2A1 CNV is associated with the urinary concentrations of androgen sulfate metabolites.

Role of DHEA in cardiovascular diseases

Dehydroepiandrosterone (DHEA) is a steroid hormone derived from cholesterol synthesized by the adrenal glands. DHEA and its 3β-sulphate ester (DHEA-S) are the most abundant circulating steroid hormones. In human, there is a clear age-related decline in serum DHEA and DHEA-S and this has suggested that a relative deficiency in these steroids may be causally related to the development of a series of diseases associated with aging including cardiovascular diseases (CVD). This commentary aims to highlight the action of DHEA in CVD and its beneficial effect in therapy. We thus discuss the possible impact of serum DHEA decline and DHEA supplementation in diseases such as hypertension, coronary artery disease and atherosclerosis. More specifically, we provide evidence for a beneficial action of DHEA in the main disease of the pulmonary circulation: pulmonary hypertension. We also examine the potential cellular mechanism of action of DHEA in terms of receptors (membrane/nuclear) and associated signaling pathways (ion channels, calcium signaling, PI3K/AKT/eNos pathway, cGMP, RhoA/RhoK pathway). We show that DHEA acts as an anti-remodeling and vasorelaxant drug. Since it is a well-tolerated and inexpensive drug, DHEA may prove to be a valuable molecule in CVD but it deserves further studies both at the molecular level and in large clinical trials.

Dehydroepiandrosterone sulfate levels and risk of atrial fibrillation: the Rotterdam Study

BACKGROUND

High plasma dehydroepiandrosterone sulfate (DHEAS) levels have been associated with a reduced risk of cardiovascular disease and atherosclerosis. To our knowledge, no previous follow-up study has investigated the association between DHEAS and the development of atrial fibrillation. Our objective was to investigate the association between DHEAS levels and incident atrial fibrillation.

METHODS AND RESULTS

The study was based on a random sample within the prospective population-based Rotterdam Study. The study population comprised 1180 participants without atrial fibrillation at baseline for whom baseline levels of DHEAS were measured in plasma. Atrial fibrillation was ascertained from centre visit electrocardiogram (ECG) assessments as well as medical records. During a mean follow-up period of 12.3 years, 129 participants developed atrial fibrillation. DHEAS levels were inversely associated with the risk of atrial fibrillation (hazard ratio (HR) per standard deviation (SD): 0.74, 95% confidence interval (CI): 0.58-0.94). Subjects in the highest DHEAS quartile had an almost three times lower risk of atrial fibrillation during follow-up, compared to those in the lowest DHEAS quartile (HR: 0.34, 95% CI: 0.18-0.64) adjusted for age, sex and cardiovascular risk factors.

CONCLUSION

DHEAS can be regarded as an important indicator of future atrial fibrillation in both men and women, independent of known cardiovascular risk factors.

Relationship between testosterone deficiency and cardiovascular risk and mortality in adult men

Classic male hypogonadism is associated with known adverse effects including decreased libido, erectile dysfunction, osteoporosis, and changes in body composition. Recently, we have come to appreciate that reduction in serum testosterone (T) levels resulting from aging or chronic disease or androgen deprivation therapy (ADT) have consequences similar to those seen in classic male hypogonadism which include increased fat mass, decreased lean body mass, decreased muscle strength, and sexual dysfunction. These data suggest that low T levels may represent a newly recognized cardiometabolic risk factor. Therefore, we carried out a careful review of the literature, focusing on major turning points of research and studies which gave more important and controversial contribution to the cardiovascular role of T. Observational studies and clinical trials investigating the relationship between T levels and cardiovascular disease and mortality were identified byMedline search. The results were synthesized, tabulated, and interpreted. The aim of this review is to discuss the association between low T levels and adverse metabolic profile such as insulin resistance, metabolic syndrome, and diabetes. We will also investigate the potential mechanisms by which male hypogonadism, especially age related or induced by ADT, may increase cardio-metabolic risk. Finally we will detail the emerging relationship between low T and mortality in men addressing also the reverse hypothesis that low T has a protective role by turning off T-dependent functions.

Anabolic status and functional impairment in men with mild chronic heart failure

The purpose of this study was to establish the role of hormonal anabolic deficiencies in exercise intolerance in patients with chronic heart failure One hundred four consecutive men (mean age 53.1 ± 10.6 years) with established diagnoses of chronic heart failure were included. At enrollment, blood samples were taken, and echocardiography and cardiopulmonary exercise testing were carried out. Exercise capacity was expressed as peak oxygen consumption (Vo₂), predicted peak Vo₂, and the ventilatory response to exercise (VE/Vco₂) slope. The mean left ventricular ejection fraction was 29.7 ± 11.9%, and most patients (86%) were in New York Heart Association class I or II, with a mean peak Vo₂ of 18 ml/min/kg. According to the age-adjusted reference values, hormonal deficiencies were present in 29% for total testosterone, 39% for estimated free testosterone, 34% for insulin-like growth factor-1, and 61% for dehydroepiandrosterone sulfate. Dehydroepiandrosterone sulfate showed a significant correlation with peak Vo₂ (r = 0.29, p = 0.007), predicted peak Vo₂ (r = 0.28, p = 0.006), and VE/Vco₂ slope (r = -0.39, p <0.001), whereas total testosterone, estimated free testosterone, and insulin-like growth factor-1 were not significantly correlated. After adjusting in a multivariable model, dehydroepiandrosterone sulfate remained an independent predictor of each exercise parameter. In conclusion, in a cohort of patients with mild chronic heart failure, exercise capacity objectively measured using cardiopulmonary exercise testing was related to anabolic impairment of the adrenal rather than the somatotropic or peripheral axis.

Targeting sigma-1 receptor signaling by endogenous ligands for cardioprotection

INTRODUCTION

The sigma receptors, initially described as a subtype of opioid receptors, are now considered to be a unique receptor expressed in neonatal rat cardiomyocytes and in the plasma membrane of adult rat cardiomyocytes. A number of sigma receptor ligands influence cardiovascular function and the heart has binding sites for sigma receptor ligands that alter contractility both in vivo and in vitro. The human sigma-1 receptor gene contains a steroid-binding component and gonadal steroid dehydroepiandrosterone (DHEA) which interacts with the sigma-1 receptor.

AREAS COVERED

We recently documented that the pathophysiological role of the sigma-1 receptor in the heart and its modulation using DHEA, was cardioprotective. Moreover, agonist-induced activation of the sigma-1 receptor modulates diverse ion channels and thereby regulates heart function. Novel concepts for understanding the pathophysiological relevance of sigma-1 receptors in the progression of heart failure, and developing clinical therapeutics targeting for the receptor in cardiovascular diseases are discussed.

EXPERT OPINION

Future studies should attempt to develop cardiac-specific knockdown of the sigma-1 receptor to observe its downstream signaling. We expect that these observations will lead to a novel therapeutic target for which a new class of antihypertrophic drugs can be designed.

Sugar alters the level of serum insulin and plasma glucose and the serum cortisol:DHEAS ratio in female migraine sufferers

Early work has highlighted that a large percentage of migraineurs may have an altered glucidic methabolis due to carbohydrate-induced hyperinsulinism. The aim of this study was to assess the effect of sucrose on biomarkers of energy metabolism and utilization in migraineous females. A total of 16 participants (8 = Migraine, 8 = Non-migraine) at the mid-point of their menstrual cycle underwent a 15-h fast prior to ingesting 75 g sucrose dissolved in 175 g water. Blood sampling for the assessment of serum insulin, serum cortisol and serum dehydroepiandrosterone sulfate (DHEAS) and plasma glucose was conducted upon arrival at 09:00 h and then at regular 15-min intervals across a 150-min experimental period. The results showed a significant alteration in serum insulin and plasma glucose following sucrose ingestion in the migraine and non-migraine groups. In addition, significant group differences were observed in the level of serum insulin, serum DHEAS, and the cortisol:DHEAS ratio with migraine participants on average recording a higher sucrose-induced serum insulin level and lower DHEAS level and cortisol:DHEAS ratio when group data was compared. It was concluded that while sucrose consumption may potentiate serum insulin in migraineurs this does not result in the development of sucrose-induced hypoglycemia in migraine or non-migraine participants.

DHEA, important source of sex steroids in men and even more in women

A major achievement from 500 million years of evolution is the establishment of a high secretion rate of dehydroepiandrosterone (DHEA) by the human adrenal glands coupled with the indroduction of menopause which stops secretion of estrogens by the ovary. Cessation of estrogen secretion at menopause eliminates the risks of endometrial hyperplasia and cancer which would result from non-opposed estrogen stimulation during the post-menopausal years. In fact, from the time of menopause, DHEA becomes the exclusive and tissue-specific source of sex steroids for all tissues except the uterus. Intracrinology, a term coined in 1988, describes the local formation, action and inactivation of sex steroids from the inactive sex steroid precursor DHEA. Over the past 25 years most, if not all, the genes encoding the human steroidogenic and steroid-inactivating enzymes have been cloned and sequenced and their enzymatic activity characterized. The problem with DHEA, however, is that its secretion decreases from the age of 30 years and is already decreased, on average, by 60% at time of menopause. In addition, there is a large variability in the circulating levels of DHEA with some post-menopausal women having barely detectable serum concentrations of the steroid while others have normal values. Since there is no feedback mechanism controlling DHEA secretion within 'normal' values, women with low DHEA will remain with such a deficit of sex steroids for their remaining lifetime. Since there is no other significant source of sex steroids after menopause, one can reasonably believe that low DHEA is involved, in association with the aging process, in a series of medical problems classically associated with post-menopause, namely osteoporosis, muscle loss, vaginal atrophy, fat accumulation, hot flashes, skin atrophy, type 2 diabetes, memory loss, cognition loss and possibly Alzheimer's disease. A recent randomized, placebo-controlled study has shown that all the signs and symptoms of vaginal atrophy, a classical problem recognized to be due to the hormone deficiency of menopause, can be rapidly improved or corrected by local administration of DHEA without systemic exposure to estrogens. In addition, the four domains of sexual dysfucntion are improved. For the other problems of menopause, although similar large scale, randomized and placebo-controlled studies usually remain to be performed, the available evidence already strongly suggests that they could be improved, corrected or even prevented by exogenous DHEA. In men, the contribution of adrenal DHEA to the total androgen pool has been measured at 40% in 65-75-year-old men. Such data stress the necessity of blocking both the testicular and adrenal sources of androgens in order to achieve optimal benefits in prostate cancer therapy. On the other hand, the comparable decrease in serum DHEA levels observed in both sexes has less consequence in men who continue to receive a practically constant supply of testicular sex steroids during their whole life. In fact, in men, the appearance of hormone-deficiency symptoms common to women is observed at a later age and with a lower degree of severity. Consequently, DHEA replacement has shown much more easily measurable beneficial effects in women. Most importantly, despite the non-scientific and unfortunate availability of DHEA as a food supplement in the United States, a situation that discourages rigorous clinical trials on the crucial physiological and therapeutic role of DHEA, no serious adverse event related to DHEA has ever been reported in the world literature (thousands of subjects exposed) or in the monitoring of adverse events by the FDA (millions of subjects exposed), thus indicating, as expected from its known physiology, the excellent safety profile of DHEA. With today's knowledge, one can reasonably suggest that DHEA offers the promise of a safe and efficient replacement therapy for the multiple problems related to hormone deficiency after menopause without the risks associated with estrogen-based or any other treatments.

Adrenal androgen dehydroepiandrosterone sulfate inhibits vascular remodeling following arterial injury

Recent epidemiologic studies have suggested that serum dehydroepiandrosterone sulfate (DHEAS) levels have a significant inverse correlation with the incidence of cardiovascular diseases. However, direct evidence for the association with DHEAS and vascular disorders has not yet been explored. DHEAS significantly reduced neointima formation 28 days after surgery without altering other serum metabolite levels in a rabbit carotid balloon injury model. Immunohistochemical analyses revealed the reduction of proliferating cell nuclear antigen (PCNA) index and increase of TdT-mediated dUTP-biotin Nick End Labeling (TUNEL) index, expressing differentiated vascular smooth muscle cell (VSMC) markers in the media 7 days after surgery. In vitro, DHEAS exhibited inhibitory effects on VSMC proliferation and migration activities, inducing G1 cell cycle arrest with upregulation of one of the cyclin dependent kinase (CDK) inhibitors p16(INK4a) and apoptosis with activating peroxisome proliferator-activated receptor (PPAR)-alpha in VSMCs. DHEAS inhibits vascular remodeling reducing neointima formation after vascular injury via its effects on VSMC phenotypic modulation, functions and apoptosis upregulating p16(INK4a)/activating PPARalpha. DHEAS may play a pathophysiological role for vascular remodeling in cardiovascular disease.

Variation in estrogen-related genes associated with cardiovascular phenotypes and circulating estradiol, testosterone, and dehydroepiandrosterone sulfate levels

BACKGROUND

Younger age at the onset of menopause and lower circulating levels of estrogen are risk factors for cardiovascular disease. Several studies have detected associations between variations in genes encoding estrogen receptors alpha (ESR1) and beta (ESR2), and enzyme aromatase (CYP19A1), which regulates the estrogen to testosterone ratio, and cardiovascular phenotypes in the Framingham Heart Study. To explore potential mechanisms by which these gene variants may contribute to cardiovascular disease, we tested the hypothesis that the polymorphisms were associated with endogenous steroid hormone levels.

METHODS

Multiple regression analysis was used to assess the relation between reported polymorphisms and total serum estradiol, testosterone, and dehydroepiandrosterone sulfate levels in 834 men and 687 women who attended the third and fourth Framingham Heart Study examination cycles.

RESULTS

In men, significant associations were detected between CYP19A1 polymorphisms and estradiol and testosterone levels, and the estradiol to testosterone ratio (P ranges 0.0005-0.01). Specifically, carriers of common haplotype rs700518[G]-(TTTA)(n) [L]-rs726547[C] had higher estradiol levels (5% per copy; P = 0.0004), lower testosterone levels (17% per copy; P = 0.036), and a higher estradiol to testosterone ratio (24% per copy; P < 0.0001) compared with the rs700518[A]-(TTTA)(n) [S]-rs726547[C] carriers. In addition, postmenopausal carriers of the ESR2 (CA)(n) long allele and rs1256031 [C] allele had moderately higher estradiol levels (P < or = 0.03). No significant associations with the ESR1 variants were detected.

CONCLUSIONS

Our findings suggest that variations in CYP19A1 correlate with steroid hormone levels in men. Knowledge that a specific carrier status may predispose to altered steroid hormone levels may lead to targeted intervention strategies to reduce health risks in genetically susceptible individuals.

Dehydroepiandrosterone sulfate and insulin resistance in patients with polycystic ovary syndrome

OBJECTIVE

To test the hypothesis that increasing DHEAS levels is associated with improved insulin resistance in patients with polycystic ovary syndrome (PCOS).

DESIGN

Cross-sectional cohort analysis.

SETTING

Academic medical center.

PATIENT(S)

Three hundred fifty-two women with PCOS.

INTERVENTION(S)

Patients presenting for evaluation of symptoms related to androgen excess were evaluated physically and biochemically through laboratory analysis.

MAIN OUTCOME MEASURE(S)

Circulating DHEAS, total T, free T, sex hormone-binding globulin (SHBG), and 17-hydroxyprogesterone (17-OHP) levels, and calculated homeostasis model assessment of insulin resistance (HOMA-IR).

RESULT(S)

Bivariate analysis indicated that all parameters were associated with HOMA-IR, except 17-OHP and age, and confirmed a negative correlation between DHEAS and HOMA-IR. Multivariate analysis indicated that increases in DHEAS, SHBG, 17-OHP, and age were associated with decreasing HOMA-IR, whereas increases in free T, body mass index (BMI), and waist-to-hip ratio (WHR) were associated with increasing HOMA-IR. In decreasing order of importance, the following variables predicted insulin resistance: BMI > WHR > age > DHEAS > free T > SHBG > 17-OHP.

CONCLUSION(S)

DHEAS is negatively correlated to insulin resistance in patients with PCOS, and in our model ranked just behind other well-established predictors including BMI, WHR, and age. Whether this is due to a direct beneficial effect on insulin action by adrenal androgens such as DHEA, or whether DHEAS simply reflects the circulating levels of hyperinsulinemia, remains to be determined.

Endogenous testosterone and endothelial function in postmenopausal women

OBJECTIVE

It is well known that coronary heart disease incidence increases in women after menopause. This phenomenon was related to reduced levels of female sex hormones. Estrogen decline, however, is not the only hormonal change during the postmenopausal period and estrogen administration did not protect women from cardiovascular disease. Therefore, it is justified to explore other hormonal changes. The role of androgens is still controversial. The aim of the present study was to investigate the relationship between endogenous sex hormones and endothelial function, measuring the brachial artery flow-mediated dilation.

METHODS AND RESULTS

Sixty postmenopausal women were consecutively enrolled and underwent a clinical and biochemical examination. Brachial artery flow-mediated dilation was also evaluated by ultrasound. After correction for confounding variables, testosterone was positively correlated to flow-mediated dilation (beta=0.277, P=0.03). Indeed, women in the lowest testosterone tertile had a flow-mediated dilation smaller than that in the highest tertile (P=0.02).

CONCLUSIONS

This result could suggest that the development of cardiovascular disease after menopause is due not only to estrogen decline but also to androgen decline. More studies are needed to evaluate the role of androgen replacement therapy on postmenopausal women with low level of this hormone.

Testosterone and atherosclerosis in aging men: purported association and clinical implications

Two of the strongest independent risk factors for coronary heart disease (CHD) are increasing age and male sex. Despite a wide variance in CHD mortality between countries, men are consistently twice as likely to die from CHD than their female counterparts. This sex difference has been attributed to a protective effect of female sex hormones, and a deleterious effect of male sex hormones, upon the cardiovascular system. However, little evidence suggests that testosterone exerts cardiovascular harm. In fact, serum levels of testosterone decline with age, and low testosterone is positively associated with other cardiovascular risk factors. Furthermore, testosterone exhibits a number of potential cardioprotective actions. For example, testosterone treatment is reported to reduce serum levels of the pro-inflammatory cytokines interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha, and to increase levels of the anti-inflammatory cytokine IL-10; to reduce vascular cell adhesion molecule (VCAM)-1 expression in aortic endothelial cells; to promote vascular smooth muscle and endothelial cell proliferation; to induce vasodilatation and to improve vascular reactivity, to reduce serum levels of the pro-thrombotic factors plasminogen activator inhibitor (PAI)-1 and fibrinogen; to reduce low-density lipoprotein-cholesterol (LDL-C); to improve insulin sensitivity; and to reduce body mass index and visceral fat mass. These actions of testosterone may confer cardiovascular benefit since testosterone therapy reduces atheroma formation in cholesterol-fed animal models, and reduces myocardial ischemia in men with CHD. Consequently, an alternative hypothesis is that an age-related decline in testosterone contributes to the atherosclerotic process. This is supported by recent findings, which suggest that as many as one in four men with CHD have serum levels of testosterone within the clinically hypogonadal range. Consequently, restoration of serum levels of testosterone via testosterone replacement therapy could offer cardiovascular, as well as other, clinical advantages to these individuals.

The Dehydroepiandrosterone And WellNess (DAWN) study: research design and methods

Levels of dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEAS), the major secretory products of the adrenal gland, decline dramatically with age, concurrent with the onset of degenerative changes and chronic diseases associated with aging. Epidemiological evidences in humans and animal studies suggest that DHEA(S) may have cardioprotective, antiobesity, antidiabetic, and immuno-enhancing properties. These observations led to the proposal that restoration of DHEA to young adult levels may have beneficial effects on age-related conditions. Most clinical trials of DHEA replacement have been limited due to small samples and short duration, restriction to one sex, failure to adjust for baseline endogenous hormone level and age, or lack of placebo comparison groups. We designed a double blind, placebo-controlled randomized trial to determine the acceptability, benefits, and adverse effects of 50 mg daily oral DHEA replacement for one year in 110 men and 115 women, aged 55 to 85, who were healthy and not currently using hormone therapy. A wide range of biological outcomes were studied including bone mineral density and metabolism, body composition and muscle strength, immune function, and cardiovascular risk factors. Steroid hormone levels, bone markers, cytokines, and the IGF-I, IGF binding protein system were measured at baseline and at 3 follow-up clinic visits. Changes in mood and well-being, cognitive function, and sexuality were assessed. Information on potentially confounding covariates such as smoking, alcohol consumption, exercise, diet and dietary supplements were obtained, and potential adverse effects of DHEA administration were monitored. This study enables an examination of the benefits of DHEA administration on the health of older men and women, and the influence of gender, age, and baseline endogenous DHEA level on each outcome variable. Potential mechanisms of DHEA action, including the biotransformation of DHEA to active steroids and steroid metabolites, enhancement of IGF-I bioavailability, and inhibition of IL-6 production can also be evaluated.

Relationship between androgenic hormones and arterial stiffness, based on longitudinal hormone measurements

Circulating testosterone levels (T) decrease with age in men. Low T has been associated with coronary disease and with risk factors for atherosclerosis. This study examines the relationship in men between androgenic hormones and arterial stiffness, a major risk factor for cardiovascular events. T, sex hormone-binding globulin (SHBG), and dehydroepiandrosterone sulfate (DHEAS) were measured longitudinally over 33 yr (follow-up 11.8 +/- 8.3 yr) in 901 men from the Baltimore Longitudinal Study of Aging, of whom 206 (68.1 +/- 13.7 yr) underwent carotid duplex ultrasonography. The 901 men were used to characterize age-associated hormone levels by means of mixed-effects models. Hormone values were estimated for the 206 men at the time of ultrasonography. Free T index (FTI) was calculated by dividing T by SHBG. The arterial stiffness index was calculated from peak systolic and end diastolic diameters of the common carotid artery and simultaneous brachial artery blood pressure. T, FTI, and DHEAS were correlated negatively with age, pulse pressure (PP), and stiffness index (each P < 0.01), whereas SHBG was correlated positively with age and stiffness index (P < 0.01). However, T was the only hormone that predicted the stiffness index after adjustment for age, PP, fasting plasma glucose, body mass index, and total cholesterol. T values 5-10 yr before the carotid study also predicted the stiffness index (P < 0.05). Thus the adverse influence of low T on the cardiovascular system in men may be mediated in part via the effects of T on vascular structure and function.

The decline of androgen levels in elderly men and its clinical and therapeutic implications

Aging in men is accompanied by a progressive, but individually variable decline of serum testosterone production, more than 20% of healthy men over 60 yr of age presenting with serum levels below the range for young men. Albeit the clinical picture of aging in men is reminiscent of that of hypogonadism in young men and decreased testosterone production appears to play a role in part of these clinical changes in at least some elderly men, the clinical relevancy of the age-related decline in sex steroid levels in men has not been unequivocally established. In fact, minimal androgen requirements for elderly men remain poorly defined and are likely to vary between individuals. Consequently, borderline androgen deficiency cannot be reliably diagnosed in the elderly, and strict differentiation between "substitutive" and "pharmacological" androgen administration is not possible. To date, only a few hundred elderly men have received androgen therapy in the setting of a randomized, controlled study, and many of these men were not androgen deficient. Most consistent effects of treatment have been on body composition, but to date there is no evidence-based documentation of clinical benefits of androgen administration to elderly men with normal or moderately low serum testosterone in terms of diminished morbidity or of improved survival or quality of life. Until the long-term risk-benefit ratio for androgen administration to elderly is established in adequately powered trials of longer duration, androgen administration to elderly men should be reserved for the minority of elderly men who have both clear clinical symptoms of hypogonadism and frankly low serum testosterone levels.

Dehydroepiandrosterone Sulfate Induces Acute Vasodilation of Porcine Coronary Arteries In Vitro and In Vivo

Although an inverse relationship between dehydroepiandrosterone sulfate (DHEAS) and coronary artery disease has been demonstrated in men, the vascular effects of DHEAS are not well defined. The vasoactive effects of intracoronary DHEAS and testosterone (0.1 nM to 1 microM) were examined in vivo in 24 pigs. Epicardial cross-sectional area was measured by intravascular ultrasound, and coronary flow velocity by intravascular Doppler velocimetry. We also examined the effects of antagonism of the androgen receptor, nitric oxide synthase, and potassium channels on DHEAS-induced vasodilation in vitro in coronary rings from male and female pig hearts. DHEAS and testosterone induced increases in cross-sectional area, average peak velocity, and coronary blood flow. The maximal increase in coronary blood flow in response to testosterone was 1.26-fold (P=0.02), and in average peak velocity 1.43-fold (P=0.05), greater than that to DHEAS, whereas increases in cross-sectional area were similar. Vasodilation to both hormones was rapid, with maximal responses occurring <10 minutes after administration. In vitro, DHEAS and testosterone induced vasodilation in coronary rings, greater with testosterone. At doses of 0.1 and 1 microM, the vasodilator effects of DHEAS and testosterone were inhibited by the androgen receptor antagonist flutamide but not the estrogen receptor antagonist ICI 182,780. At 10 microM, neither DHEAS- nor testosterone-induced vasorelaxation was inhibited by flutamide, ICI 182,780, L-NAME, or deendothelialization, but both were attenuated by pretreatment with glibenclamide. No gender differences were observed in any of the responses examined. In conclusion, DHEAS is an acute coronary artery vasodilator, but less potent than testosterone. Its effect might be mediated via androgen receptors and may involve ATP-sensitive potassium channels.

Association of decrease in serum dehydroepiandrosterone sulfate levels with the progression to type 2 diabetes in men of a Japanese population: the Funagata Study

Association of serum dehydroepiandrosterone sulfate (DHEAS) levels with insulin resistance and impairment of insulin secretion have been reported. We here examined the association of serum DHEAS levels with type 2 diabetes mellitus (DM) and the progression to DM. The serum DHEAS levels at baseline (from 1995 to 1997) were evaluated in 1709 individuals (998 women and 711 men) from a cohort population (n = 3706) of the Funagata Study. Glucose tolerance was evaluated at baseline as well as at 5-year follow-up examinations (n = 970, follow-up rate, 56.8%) according to the 1985 World Health Organization criteria. The statistical significance of the difference between any 2 groups was determined by the Student t test. Multiple logistic regression analysis determined the association of the traits with the progression to DM at the 5-year follow-up examinations. P < .05 was accepted as statistically significant. The serum DHEAS levels were significantly lower in DM than in normal glucose tolerance. However, this difference was not significant when adjusted for age. In men, the decrease in serum DHEAS levels by the 5-year follow-up examinations was significantly larger in the subjects who became diabetic than in the subjects who remained normal glucose tolerance, even when adjusted for age ( P = .0003). Multiple logistic regression analysis revealed a significant association of the decrease in serum DHEAS levels with the progression to DM, with an odds ratio (per 0.1 log ng/mL) of 1.410 (95% confidence interval [CI], 1.020-1.948, P = .038), independently from age, height, and 2-hour plasma glucose in men. A decrease in serum DHEAS levels seems to be associated with the progression to DM in Japanese men.

The Use of Dehydroepiandrosterone Therapy in Clinical Practice

Dehydroepiandrosterone (DHEA) therapy is controversial due to sensationalized reports of epidemiologic studies and the over-the-counter availability of DHEA. Human clinical trials have investigated the potential efficacy of DHEA therapy in multiple conditions with resultant inconsistencies in findings. DHEA is unique compared with other adrenal steroids because of the fluctuation in serum levels found from birth into advancing age. The lower endogenous levels of DHEA and DHEA sulfate found in advancing age have been correlated with a myriad of health conditions. Also, some studies suggest gender-specific actions of endogenous and exogenous DHEA. We reviewed only pharmacokinetic studies and human clinical trials investigating the efficacy of DHEA therapy that were placebo-controlled as these provided the most reliable scientific basis for the evaluation of DHEA therapy. Pharmacodynamic studies suggest that doses of 30-50mg of oral DHEA may produce physiologic androgen levels, especially in women. These studies report a dose-dependent effect and lack of accumulation of serum androgen levels. Pharmacologic studies also reveal a gender-specific response to DHEA therapy such that testosterone levels are increased in women but not in men. Clinical trials suggest that 50mg of oral DHEA, but not <30mg, can increase serum androgen levels to within the physiologic range for young adults with primary and secondary adrenal insufficiency, possibly improve sexual function, improve mood and self-esteem, and decrease fatigue/exhaustion. Whereas DHEA replacement therapy may be effective in treating patients with adrenal insufficiency, human clinical trials investigating its efficacy in conditions such as systemic lupus erythematosus, HIV, Alzheimer disease, advancing age, male sexual dysfunction, perimenopausal symptoms, depression, and cardiovascular disease have not provided consistent findings.

Effects of the long-acting calcium channel blockers, amlodipine, manidipine and cilnidipine on steroid hormones and insulin resistance in hypertensive obese patients

OBJECTIVE

To demonstrate that calcium channel blockers can improve insulin resistance clinically, we investigated the effects of the calcium channel blockers, amlodipine, manidipine and cilnidipine on serum levels of steroid hormones and insulin.

SUBJECTS AND METHODS

Thirty hypertensive obese patients [15 men and 15 women; mean age 55.9 years, mean body mass index (BMI) 27.6] were divided into three groups and treated with either 5 mg of amlodipine, 20 mg of manidipine or 10 mg of cilnidipine. Blood pressure (BP), fasting plasma glucose (FPG), HbA1c, fasting serum immunoreactive insulin (F-IRI), insulin resistance index [as assessed by the homeostasis model assessment (HOMA-R)], serum DHEA, serum DHEA-S, plasma ACTH, serum cortisol, plasma renin activity (PRA), and serum aldosterone, were measured before and after 1, 2, 3 and 6 months of treatment.

RESULTS

In all three groups, BP decreased significantly after 1 month and F-IRI and HOMA-R decreased significantly after 2-3 months. A concurrent rise in serum DHEA and DHEA-S levels was also observed, however, the differences were not significant. No changes in FPG, HbA1c, ACTH, cortisol, PRA or aldosterone levels were observed during treatment.

CONCLUSIONS

We conclude that amlodipine, manidipine and cilnidipine all improve insulin resistance and consequently increase serum levels of DHEA and DHEA-S.

Endogenous sex hormones and cardiovascular disease in men

Unlike women, men do not experience an abrupt reduction in endogenous sex hormone production. It has, however, become clear that an age-associated decrease in the levels of (bioactive) sex hormones does occur. Whether endogenous sex hormones have an impact on cardiovascular disease has for many years remained largely unknown, but during the last decade more attention has been drawn to the importance of testosterone, estrogens, and adrenal androgens in etiology, prevention, and treatment of male cardiovascular disease. The purpose of this article is to summarize the evidence currently available on the association between endogenous sex hormones and cardiovascular disease in males. Published studies dealing with the relationship between circulating levels of sex hormones and cardiovascular disease in males were reviewed. The studies reviewed in this article suggest that circulating endogenous sex hormones and estrogens have a neutral or beneficial effect on cardiovascular disease in men.

Dehydroepiandrosterone modulates endothelial nitric oxide synthesis via direct genomic and nongenomic mechanisms

Dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) are the major circulating steroid hormones in humans, and their levels progressively decline with age. Epidemiological studies suggest that DHEA/DHEAS concentrations may be inversely related to cardiovascular risk, but disagreement exists on this issue. Preliminary studies show that DHEA regulates vascular function, but few data have been published on the mechanisms. We show that DHEA administration to human endothelial cells triggers nitric oxide synthesis, due to enhanced expression and stabilization of endothelial nitric oxide synthase (eNOS). Additionally, DHEA rapidly activates eNOS, through a nontranscriptional mechanism that depends on ERK1/2 MAPK, but not on phosphatidylinositol 3-kinase/Akt. DHEA is not converted to estrogens or androgens by endothelial cells, and its genomic and nongenomic effects are not blocked by antagonists of the estrogen, progesterone, glucocorticoid, or androgen receptors, suggesting that DHEA acts through a specific receptor. Oral DHEA administration to ovariectomized Wistar rats dose-dependently restores aortic eNOS levels and eNOS activity, confirming the effects of DHEA in vivo. Our present data suggest that DHEA may have direct genomic and nongenomic effects on the vascular wall that are not mediated by other steroid hormone receptors, leading to eNOS activation and induction.

The effect of dehydroepiandrosterone on coronary blood flow in prepubertal anaesthetized pigs

Extensive research suspecting an association between plasma levels of dehydroepiandrosterone and the risk of coronary heart disease has not been conclusive. The present study was designed to investigate the effect of dehydroepiandrosterone on the coronary circulation and to determine the mechanisms involved. In prepubertal pigs of both sexes anaesthetized with sodium pentobarbitone, changes in left circumflex or anterior descending coronary flow caused by intravenous infusion of dehydroepiandrosterone were assessed using an electromagnetic flowmeter. Changes in heart rate and arterial pressure were prevented by atrial pacing and by connecting the arterial system to a pressurized reservoir containing Ringer solution. In 20 pigs, infusion of 1 mg h-1 of dehydroepiandrosterone caused a decrease in coronary flow without affecting left ventricular dP/dtmax (rate of change of left ventricular systolic pressure) and filling pressures of the heart. In a further eight pigs, a dose-response curve was obtained by graded increases in the infused dose of hormone between 0.03 and 4 mg h-1. The mechanisms of the above response were studied in the 20 pigs by repeating the experiment after haemodynamic variables had returned to the control values observed before infusion. Blockade of muscarinic cholinoceptors with intravenous atropine (five pigs) and of alpha-adrenoceptors with intravenous phentolamine (five pigs) did not affect the dehydroepiandrosterone-induced coronary vasoconstriction. This response was abolished by blockade of beta-adrenoceptors with intravenous propranolol (five pigs) and of coronary nitric oxide synthase with intracoronary injection of Nomega-nitro-L-arginine methyl ester (five pigs) even after reversing the increase in arterial pressure and coronary vascular resistance caused by the two blocking agents with intravenous infusion of papaverine. The present study showed that intravenous infusion of dehydroepiandrosterone primarily caused coronary vasoconstriction. The mechanisms of this response were shown to involve the inhibition of a vasodilatory beta-adrenergic receptor-mediated effect related to the release of nitric oxide.

Androgens and coronary artery disease

A significant and independent association between endogenous testosterone (T) levels and coronary events in men and women has not been confirmed in large prospective studies, although cross-sectional data have suggested coronary heart disease can be associated with low T in men. Hypoandrogenemia in men and hyperandrogenemia in women are associated with visceral obesity; insulin resistance; low high-density lipoprotein (HDL) cholesterol (HDL-C); and elevated triglycerides, low-density lipoprotein cholesterol, and plasminogen activator type 1. These gender differences and confounders render the precise role of endogenous T in atherosclerosis unclear. Observational studies do not support the hypothesis that dehydroepiandrosterone sulfate deficiency is a risk factor for coronary artery disease. The effects of exogenous T on cardiovascular mortality or morbidity have not been extensively investigated in prospective controlled studies; preliminary data suggest there may be short-term improvements in electrocardiographic changes in men with coronary artery disease. In the majority of animal experiments, exogenous T exerts either neutral or beneficial effects on the development of atherosclerosis. Exogenous androgens induce both apparently beneficial and deleterious effects on cardiovascular risk factors by decreasing serum levels of HDL-C, plasminogen activator type 1 (apparently deleterious), lipoprotein (a), fibrinogen, insulin, leptin, and visceral fat mass (apparently beneficial) in men as well as women. However, androgen-induced declines in circulating HDL-C should not automatically be assumed to be proatherogenic, because these declines may instead reflect accelerated reverse cholesterol transport. Supraphysiological concentrations of T stimulate vasorelaxation; but at physiological concentrations, beneficial, neutral, and detrimental effects on vascular reactivity have been observed. T exerts proatherogenic effects on macrophage function by facilitating the uptake of modified lipoproteins and an antiatherogenic effect by stimulating efflux of cellular cholesterol to HDL. In conclusion, the inconsistent data, which can only be partly explained by differences in dose and source of androgens, militate against a meaningful assessment of the net effect of T on atherosclerosis. Based on current evidence, the therapeutic use of T in men need not be restricted by concerns regarding cardiovascular side effects. Available data also do not justify the uncontrolled use of T or dehydroepiandrosterone for the prevention or treatment of coronary heart disease.

DHEA and sport

Dehydroepiandrosterone (DHEA), a 19-carbon steroid, is situated along the steroid metabolic pathway. It is the most abundant circulating hormone in the body and can be converted to either androgens or estrogens. It is readily conjugated to its sulphate ester DHEAS, and they are designated as DHEA(S) here when used together. Its secretion reaches a peak in early adulthood and thereafter decreases, until approximately age 70 years when it reaches a concentration of approximately 20%. Many hormonal changes may take place with aging but none is as marked as this. This "relative DHEA deficiency" resulted in DHEA being enthusiastically labelled by some as a fountain of youth or an antidote to aging that would prove to be the panacea they are seeking. Its use was also taken up enthusiastically by the athletic community and used as a prohormone in the belief or hope that it would be converted mainly to testosterone in the body.

Dehydroepiandrosterone activates endothelial cell nitric-oxide synthase by a specific plasma membrane receptor coupled to Galpha(i2,3)

The adrenal steroid dehydroepiandrosterone (DHEA) has no known cellular receptor or unifying mechanism of action, despite evidence suggesting beneficial vascular effects in humans. Based on previous data from our laboratory, we hypothesized that DHEA binds to specific cell-surface receptors to activate intracellular G-proteins and endothelial nitric-oxide synthase (eNOS). We now pharmacologically characterize a putative plasma membrane DHEA receptor and define its associated G-proteins. The [3H]DHEA binding to isolated plasma membranes from bovine aortic endothelial cells was of high affinity (K(d) = 48.7 pm) and saturable (B(max) = 500 fmol/mg protein). Structurally related steroids failed to compete with DHEA for binding. The putative DHEA receptor was functionally coupled to G-proteins, because guanosine 5'-O-(3-thio)triphosphate (GTPgammaS) inhibited [3H]DHEA binding to plasma membranes by 69%, and DHEA increased [35S]GTPgammaS binding by 157%. DHEA stimulated [35S]GTPgammaS binding to Galpha(i2) and Galpha(i3), but not to Galpha(i1) or Galpha(o). Pretreatment of plasma membranes with antibody to Galpha(i2) or Galpha(i3), but not to Galpha(i1), inhibited the DHEA activation of eNOS. Thus, DHEA receptors are expressed on endothelial cell plasma membranes and are coupled to eNOS activity through Galpha(i2) and Galpha(i3). These novel findings should allow us to isolate the putative receptor and reevaluate the physiological role of DHEA activity.

Oral nutritional supplements and heart disease: a review

The use of nutritional supplements in the treatment of cardiovascular disease is rapidly growing in the United States. Many substances are marketed with anecdotal claims of efficacy. Most have not been scientifically studied. Excitement exists in the lay press about the homocysteine hypothesis of coronary artery disease and vitamin cures. A MEDLINE search and review of papers covering the study of popular nutritional supplements were undertaken. The papers were limited to peer-review journals using patient series reports, double-blinded prospective studies, and population studies. A compendium of the available data was obtained and an analysis of each paper's methodology was done. A review of the most popular and most studied oral nutritional supplements for the treatment of heart disease demonstrated relatively few well-founded indications for the widespread application of substances with the exception of the bioflavonoids. Some modest effects for endothelial dysfunction were noted for vitamins C and E. Red wines and beers were also noted to be beneficial. The majority of substances either had no effect or were deleterious.

Low dehydroepiandrosterone and ischemic heart disease in middle-aged men: prospective results from the Massachusetts Male Aging Study

The adrenal steroid dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) have been characterized as "protective" against ischemic heart disease (IHD), especially in men, on the basis of sparse epidemiologic evidence. The authors used data from the Massachusetts Male Aging Study, a random sample prospective study of 1,709 men aged 40-70 years at baseline, to test whether serum levels of DHEA or DHEAS could predict incident IHD over a 9-year interval. At baseline (1987-1989) and follow-up (1995-1997), an interviewer-phlebotomist visited each subject in his home to obtain comprehensive health information, body measurements, and blood samples for hormone and lipid analysis. Incident IHD between baseline and follow-up was ascertained from hospital records and death registries, supplemented by self-report and evidence of medication. In the analysis sample of 1,167 men, those with serum DHEAS in the lowest quartile at baseline (<1.6 microg/ml) were significantly more likely to incur IHD by follow-up (adjusted odds ratio = 1.60, 95 percent confidence interval: 1.07, 2.39; p = 0.02), independently of a comprehensive set of known risk factors including age, obesity, diabetes, hypertension, smoking, serum lipids, alcohol intake, and physical activity. Low serum DHEA was similarly predictive. These results confirm prior evidence that low DHEA and DHEAS can predict IHD in men.

The plasma levels of dehydroepiandrosterone sulfate are decreased in patients with chronic heart failure in proportion to the severity

Dehydroepiandrosterone sulfate (DHEAS) is the major secretory steroid of the human adrenal glands. The secretion of DHEAS decreases with aging. The incidence of heart failure also rises in the elderly population. We measured the plasma levels of DHEAS and cortisol in 49 patients with chronic heart failure (CHF) and 32 age-matched controls and assessed its relation to plasma levels of A-type natriuretic peptide and B-type natriuretic peptide, biochemical markers of heart failure. Plasma levels of DHEAS were significantly lower in patients with CHF than in controls, whereas there was no significant difference in plasma levels of cortisol between the two groups. In stepwise regression analysis, the plasma level of DHEAS was significantly and independently correlated with age (beta = -0.451; P < 0.0001) and the plasma level of B-type natriuretic peptide (beta = -0.338; P < 0.001), and the plasma cortisol/DHEAS ratio was significantly and independently correlated with the plasma levels of A-type natriuretic peptide (beta = 0.598; P < 0.0001) and thiobarbituric acid-reactive substances (a marker of oxidative stress; beta = 0.252; P < 0.01) and age (beta = 0.171; P < 0.05). These results indicate that the plasma levels of DHEAS are decreased in patients with CHF in proportion to its severity and that oxidative stress is associated with decreased levels of DHEAS in patients with CHF.

The influence of dehydroepiandrosterone on histology of selected organs in rabbits on an atherogenic diet

The influence of dehydroepiandrosterone (DHEA) in fodder on the histology of selected organs in rabbits with induced hypercholesterolemia and in healthy rabbits was studied. Rabbits were randomly assigned into four groups: (1) control; (2) atherogenic diet; (3) atherogenic diet with addition of DHEA; (4) normal diet with addition of DHEA. After 12 weeks, the rabbits were bled. Tissue samples were collected, fixed in a 0.4% solution of buffered formalin, dehydrated and embedded in paraffin. Fragments of 5-7 microns were stained with hematoxylin and eosin as well as according to the van Gieson method. Histological analysis showed features of steatosis and intense degenerative changes in analyzed organs of animals from group 2, i.e. liver, kidneys, adrenal glands, lungs and bone. The degenerative changes in the group which in addition to a fat-rich diet received DHEA, were similar to group 2, but much less intense. Histological pictures of organs of the rabbits which received DHEA and normal diet did not differ significantly from the control group. In animals with experimental hyperlipidemia, DHEA acts protectively, decreasing degenerative changes in internal organs caused by an atherogenic diet. DHEA does not change the histological picture of organs in healthy animals.

Effects of dehydroepiandrosterone on mitogen-activated protein kinase in human aortic smooth muscle cells

The objective of the present study was to determine whether dehydroepiandrosterone (DHEA) modifies growth factor-induced mitogen-activated protein kinase (MAPK) activation, based on our previous study demonstrating that DHEA attenuates fetal calf serum-induced proliferation in human male aortic smooth muscle cells (human male aortic SMCs). Human male aortic SMCs were used for this study. Platelet-derived growth factor-BB (PDGF-BB), epidermal growth factor (EGF), and basic fibroblast growth factor (bFGF), but not insulin-like growth factor-1 (IGF-1), stimulated MAPK activity. Only MAPK activation induced by PDGF-BB was reduced by pretreatment with DHEA, although DHEA did not affect the MAPK activation induced by EGF or bFGF. The basal and PDGF-stimulated MAPK activity were decreased by two types of cyclic AMP (cAMP) elevating agents and increased by cAMP-dependent protein kinase (PKA) inhibitor in human male aortic SMCs, suggesting that cAMP regulates MAPK negatively. The intracellular cAMP was increased by PDGF-BB. The increase of cAMP by PDGF-BB was augmented by pretreatment with DHEA, although DHEA alone did not affect cAMP. Neither EGF nor bFGF affected cAMP with and without DHEA pretreatment. Secretion of PGE2 induced by PDGF was augmented by pretreatment with DHEA. Stimulatory effects of DHEA on the production of PGE2 and cAMP were partially canceled by aromatase inhibitor and completely canceled by indomethacin or selective inhibitor of cyclooxygenase-2. These results suggest that DHEA inhibited MAPK activation induced by PDGF-BB via PGE2 overproduction and subsequent cAMP-dependent pathway in human male aortic SMCs.

Relation of dehydroepiandrosterone and dehydroepiandrosterone sulfate with cardiovascular disease risk factors in women: longitudinal results from the Massachusetts Women's Health Study

Low circulating levels of the adrenal steroids dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are thought to be associated with increased risk of cardiovascular disease (CVD) in men. In women, either a positive or null association with CVD has been found. The nature of the relation between DHEAS and CVD risk factors in women is unclear and is based on cross-sectional data. We present results from a longitudinal investigation of serum DHEA and DHEAS and cardiovascular disease risk factors in 236 women, initially 50-60 years old, from a population-based prospective (1986-1995) study of the menopausal transition. We used generalized estimating equations to model the relation of serum DHEA and DHEAS to systolic and diastolic blood pressure and serum levels of total cholesterol, high density lipoprotein cholesterol, and apolipoproteins A and B, adjusting for other factors related to CVD. Both DHEA and DHEAS were positively related to diastolic and systolic blood pressure, and DHEAS was negatively related to apolipoprotein A. DHEA and DHEAS were also positively related to smoking, alcohol use, estrone, and estradiol levels, and inversely related to age. Our results suggest that higher levels of DHEA and DHEAS in middle-aged women may indicate increased CVD risk.

von Willebrand factor, tissue plasminogen activator, and dehydroepiandrosterone sulphate predict cardiovascular death in a 10 year follow up of survivors of acute myocardial infarction

BACKGROUND

Haemostasis plays a major part in the process initiating a myocardial infarction. The impact of haemostatic variables on long term prognosis is unknown.

OBJECTIVE

To evaluate von Willebrand factor (vWF), tissue plasminogen activator antigen (t-PA) and its activity before and after venous occlusion, plasminogen activator inhibitor (PAI-1), dehydroepian-drosterone sulphate (DHEAS), and established clinical risk factors as long term predictors for reinfarction and mortality.

PATIENTS

123 consecutive survivors of myocardial infarction followed up for 10 years.

DESIGN

Study entry took place between 1982 and 1983. Fifty seven patients died (54 of cardiovascular disease) during the mean observation time of 10 years.

RESULTS

Cox's univariate regression analysis showed that cardiovascular mortality was significantly associated with age, hypertension, previous history of angina pectoris, DHEAS, mass concentration of t-PA, and vWF. These associations were significant for vWF and mass concentration of t-PA after adjusting for age and hypertension.

CONCLUSIONS

A low concentration of DHEAS and high levels of the endothelially derived haemostatic variables vWF and mass concentration of t-PA are predictors of cardiovascular mortality in survivors of myocardial infarction. This association is independent of established clinical risk factors for mass concentration of t-PA and vWF.

Is there a case for DHEA replacement?

There are many hormonal changes that occur with ageing in humans, of which the most dramatic and intriguing change occurs for the adrenal androgenic steroid dehydroepiandosterone (DHEA). There are tantalizing epidemiological data demonstrating a significant association between the changes in circulating DHEA level and changes in the incidence of malignancy, atherosclerosis, Alzheimer's disease and other age-related changes. The pharmacological effects in animals such as rodents and rabbits have demonstrated many beneficial effects, for example increased immune function, the prevention of atherosclerosis, cancer, diabetes and obesity, and the improvement of memory. Clinical studies carried out in small groups of subjects have clearly demonstrated that the administration of DHEA to the elderly increases many hormone levels, including that of insulin-like growth factor-1, (free and total) testosterone, dihydrotestosterone, oestrone and oestradiol. It remains to be clearly defined whether these changes are clinically beneficial, and there is only insufficient information on the side-effects on long-term use. Results from short-term intervention studies in small groups of subjects have not demonstrated any convincing beneficial effects so far. A judgement on whether DHEA replacement has a place in preventing age-related disabilities could be determined only on the basis of results from studies of long-term DHEA replacement in elderly people.

Dehydroepiandrosterone Supplements: Bringing Sense to Sensational Claims

OBJECTIVE

To summarize the current information about dehydroepiandrosterone (DHEA), a steroid hormone produced in the adrenal cortex.

METHODS

The biochemical and physiologic features of DHEA and its purported effects on overall age-related decline and on various disorders are reviewed. In addition, the potential side effects from administration of DHEA are discussed.

RESULTS

During the normal life cycle, levels of DHEA fluctuate, beginning with production of large quantities in the fetus, stopping at birth, resuming during ages 5 to 7 years, and increasing throughout puberty to maximal production in the 20s. Thereafter, DHEA levels progressively decline. This age-related decline in physiologic levels of DHEA has prompted speculation about a relationship between relative "DHEA deficiency" in older age and diseases of aging as well as the possibility of deriving benefits from administration of DHEA. Certain studies in animals (primarily rodents) have suggested anticancer effects of DHEA in pharmacologic doses and improvement in metabolism. In various studies in animals and humans, discrepant results have been found in the assessment of the association between DHEA levels and coronary artery disease. Likewise, the clinical significance of changes in immune function with DHEA treatment is unknown. Because DHEA is classified as a "nutritional supplement," it is not subjected to government regulation, and a potential exists for inaccurate dosage and impurities.

CONCLUSION

Studies have shown that DHEA influences multiple systems and disease processes in animals and humans; some of these effects could be considered beneficial and others detrimental. To date, no long-term health benefits from DHEA in "replacement" doses have been demonstrated.