Low dehydroepiandrosterone circulating levels in premenopausal obese women with very high body mass index

Role of the Sodium-Dependent Organic Anion Transporter (SOAT/SLC10A6) in Physiology and Pathophysiology

The sodium-dependent organic anion transporter (SOAT, gene symbol SLC10A6) specifically transports 3'- and 17'-monosulfated steroid hormones, such as estrone sulfate and dehydroepiandrosterone sulfate, into specific target cells. These biologically inactive sulfo-conjugated steroids occur in high concentrations in the blood circulation and serve as precursors for the intracrine formation of active estrogens and androgens that contribute to the overall regulation of steroids in many peripheral tissues. Although SOAT expression has been detected in several hormone-responsive peripheral tissues, its quantitative contribution to steroid sulfate uptake in different organs is still not completely clear. Given this fact, the present review provides a comprehensive overview of the current knowledge about the SOAT by summarizing all experimental findings obtained since its first cloning in 2004 and by processing SOAT/SLC10A6-related data from genome-wide protein and mRNA expression databases. In conclusion, despite a significantly increased understanding of the function and physiological significance of the SOAT over the past 20 years, further studies are needed to finally establish it as a potential drug target for endocrine-based therapy of steroid-responsive diseases such as hormone-dependent breast cancer.

Sarcopenia in Menopausal Women: Current Perspectives

Menopause is associated with hormonal changes, which could accelerate or lead to sarcopenia. Functional impairment and physical disability are the major consequences of sarcopenia. In order to hamper these negative health outcomes, it appears necessary to prevent and even treat sarcopenia, through healthy lifestyle changes including diet and regular physical activity or through hormonal replacement therapy when appropriate. Therefore, the purpose of this narrative review will be 1) to present the prevalence of sarcopenia in postmenopausal women; 2) to address the risk factors related to sarcopenia in this specific population; and 3) to discuss how to manage sarcopenia among postmenopausal women.

Role of the Steroid Sulfate Uptake Transporter Soat (Slc10a6) in Adipose Tissue and 3T3-L1 Adipocytes

In addition to the endocrine and paracrine systems, peripheral tissues such as gonads, skin, and adipose tissue are involved in the intracrine mechanisms responsible for the formation of sex steroids via the transformation of dehydroepiandrosterone and dehydroepiandrosterone sulfate (DHEA/DHEAS) into potent androgenic and estrogenic hormones. Numerous studies have examined the relationship between overweight, central obesity, and plasma levels of DHEA and DHEAS. The sodium-dependent organic anion transporter Soat (Slc10a6) is a plasma membrane uptake transporter for sulfated steroids. Significantly increased expression of Slc10a6 mRNA has been previously described in organs and tissues of lipopolysaccharide (LPS)-treated mice, including white adipose tissue. These findings suggest that Soat plays a role in the supply of steroids in peripheral target tissues. The present study aimed to investigate the expression of Soat in adipocytes and its role in adipogenesis. Soat expression was analyzed in mouse white intra-abdominal (WAT), subcutaneous (SAT), and brown (BAT) adipose tissue samples and in murine 3T3-L1 adipocytes. In addition, adipose tissue mass and size of the adipocytes were analyzed in wild-type and Slc10a6^−/− knockout mice. Soat expression was detected in mouse WAT, SAT, and BAT using immunofluorescence. The expression of Slc10a6 mRNA was significantly higher in 3T3-L1 adipocytes than that of preadipocytes and was significantly upregulated by exposure to lipopolysaccharide (LPS). Slc10a6 mRNA levels were also upregulated in the adipose tissue of LPS-treated mice. In Slc10a6^−/− knockout mice, adipocytes increased in size in the WAT and SAT of female mice and in the BAT of male mice, suggesting adipocyte hypertrophy. The serum levels of adiponectin, resistin, and leptin were comparable in wild-type and Slc10a6^−/− knockout mice. The treatment of 3T3-L1 adipocytes with DHEA significantly reduced lipid accumulation, while DHEAS did not have a significant effect. However, following LPS-induced Soat upregulation, DHEAS also significantly inhibited lipid accumulation in adipocytes. In conclusion, Soat-mediated import of DHEAS and other sulfated steroids could contribute to the complex pathways of sex steroid intracrinology in adipose tissues. Although in cell cultures the Soat-mediated uptake of DHEAS appears to reduce lipid accumulation, in Slc10a6^−/− knockout mice, the Soat deletion induced adipocyte hyperplasia through hitherto unknown mechanisms.

Obesity, Body Composition, and Sex Hormones: Implications for Cardiovascular Risk

Cardiovascular disease (CVD) continues to be the leading cause of death in adults, highlighting the need to develop novel strategies to mitigate cardiovascular risk. The advancing obesity epidemic is now threatening the gains in CVD risk reduction brought about by contemporary pharmaceutical and surgical interventions. There are sex differences in the development and outcomes of CVD; premenopausal women have significantly lower CVD risk than men of the same age, but women lose this advantage as they transition to menopause, an observation suggesting potential role of sex hormones in determining CVD risk. Clear differences in obesity and regional fat distribution among men and women also exist. While men have relatively high fat in the abdominal area, women tend to distribute a larger proportion of their fat in the lower body. Considering that regional body fat distribution is an important CVD risk factor, differences in how men and women store their body fat may partly contribute to sex-based alterations in CVD risk as well. This article presents findings related to the role of obesity and sex hormones in determining CVD risk. Evidence for the role of sex hormones in determining body composition in men and women is also presented. Lastly, the clinical potential for using sex hormones to alter body composition and reduce CVD risk is outlined. © 2022 American Physiological Society. Compr Physiol 12:1-45, 2022.

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.

The adrenal gland in stress - Adaptation on a cellular level

Human individuals are constantly confronted to various kinds of stressors and the body's response and adaptation is essential for human health. The adrenal gland as the main producer of stress hormones plays a major role in the response to physiological challenges and is able to adapt to these physiological needs. Proper adaptation is of particular importance since dysregulation of the stress system is the cause of various human diseases including obesity, depression, Parkinson's disease, and post-traumatic stress disorder. Therefore, it is fundamental to understand the physiological, cellular, and molecular underpinnings of the stress adaptation in humans. Because of ethical reasons it is problematic to study the plasticity of the human gland in stress. Hence, various experimental models have been established for the analysis of the functional and cellular role of the adrenal gland adaptation on a translational approach. Here, we summarize the insights of stress-induced adrenal plasticity gained from these models and discuss their relevance to clinical observations.

Increased body fat mass and androgen metabolism - A twin study in healthy young women

OBJECTIVE

Obesity may alter serum steroid concentrations and metabolism. We investigated this in healthy young women with increased body fat and their leaner co-twin sisters.

DESIGN

Age and genetic background both strongly influence serum steroid levels and body composition. This is a cross-sectional study of 13 female monozygotic twin pairs (age, 23-36 years), ten of which were discordant for body mass index (median difference in body weight between the co-twins, 19 kg).

METHODS

We determined body composition by dual energy X-ray absorptiometry and magnetic resonance imaging, serum androgens by liquid chromatography-tandem mass spectrometry, and mRNA expression of genes in subcutaneous adipose tissue and adipocytes.

RESULTS

The heavier women had lower serum dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT), and sex hormone-binding globulin (SHBG) (P < 0.05 for all) compared to their leaner co-twins with no differences in serum testosterone or androstenedione levels. Serum DHEA correlated inversely with %body fat (r = -0.905, P = 0.002), and DHT positively with SHBG (r = 0.842, P = 0.002). In adipose tissue or adipocytes, expressions of STS (steroid sulfatase) and androgen-related genes were significantly higher in the heavier compared to the leaner co-twin, and within pairs, correlated positively with adiposity but were not related to serum androgen levels. None of the serum androgen or SHBG levels correlated with indices of insulin resistance.

CONCLUSIONS

Serum DHEA levels were best predicted by %body fat, and serum DHT by SHBG. These or other serum androgen concentrations did not reflect differences in androgen-related genes in adipose tissue. General or intra-abdominal adiposity were not associated with increased androgenicity in young women.

Obesity as disruptor of the female fertility

Both obesity and overweight are increasing worldwide and have detrimental influences on several human body functions including the reproductive health. In particular, obese women undergo perturbations of the 'hypothalamic pituitary ovarian axis', and frequently suffer of menstrual dysfunction leading to anovulation and infertility. Besides the hormone disorders and subfertility that are common in the polycystic ovary syndrome (PCOS), in obesity the adipocytes act as endocrine organ. The adipose tissue indeed, releases a number of bioactive molecules, namely adipokines, that variably interact with multiple molecular pathways of insulin resistance, inflammation, hypertension, cardiovascular risk, coagulation, and oocyte differentiation and maturation. Moreover, endometrial implantation and other reproductive functions are affected in obese women with complications including delayed conceptions, increased miscarriage rate, reduced outcomes in assisted conception treatments.On the contrary, weight loss programs through lifestyle modification in obese women, have been proven to restore menstrual cyclicity and ovulation and improve the likelihood of conception.

Relation BetweenBglIIPolymorphism in 3β-Hydroxysteroid Dehydrogenase Gene and Adipose Tissue Distribution in Humans

The aim of this study was to investigate the association between a restriction fragment length polymorphism (RFLP) at the 3beta-hydroxysteroid dehydrogenase locus and adipose tissue distribution phenotypes. A total of 132 unrelated individuals from the Quebec Family Study were followed prospectively for an average period of 11.3 years. The BglII polymorphism in exon 4 of the 3beta-HSD gene was detected by PCR. Body mass, body fat, and regional fat distribution indicators were adjusted for age and age2 within each gender. Associations were assessed in unrelated adults with ANOVA across three genotypes. No association was found for the indicators of body mass, body fat, and regional distribution of adipose tissue measured in 1992. In women, the changes (difference between data collected in 1992 and at entry) in the sum of six skinfolds (p=0.04), abdominal skinfold (p=0.01), and abdominal skinfold adjusted (p=0.03) for the sum of six skinfolds at entry were related to the BglII polymorphism at the 3beta-HSD locus. These relations were not found in men, but they gained less body mass and body fat over the 11.3-year period. This suggests that sequence variation at the 3beta-HSD locus or in neighboring genes on chromosome 1 may contribute to individual differences in body fat content and adipose tissue distribution in adult women, particularly in abdominal adipose tissue deposition as they grow older and gain body fat.

Do the interactions between glucocorticoids and sex hormones regulate the development of the metabolic syndrome?

The metabolic syndrome is basically a maturity-onset disease. Typically, its manifestations begin to flourish years after the initial dietary or environmental aggression began. Since most hormonal, metabolic, or defense responses are practically immediate, the procrastinated response do not seem justified. Only in childhood, the damages of the metabolic syndrome appear with minimal delay. Sex affects the incidence of the metabolic syndrome, but this is more an effect of timing than absolute gender differences, females holding better than males up to menopause, when the differences between sexes tend to disappear. The metabolic syndrome is related to an immune response, countered by a permanent increase in glucocorticoids, which keep the immune system at bay but also induce insulin resistance, alter the lipid metabolism, favor fat deposition, mobilize protein, and decrease androgen synthesis. Androgens limit the operation of glucocorticoids, which is also partly blocked by estrogens, since they decrease inflammation (which enhances glucocorticoid release). These facts suggest that the appearance of the metabolic syndrome symptoms depends on the strength (i.e., levels) of androgens and estrogens. The predominance of glucocorticoids and the full manifestation of the syndrome in men are favored by decreased androgen activity. Low androgens can be found in infancy, maturity, advanced age, or because of their inhibition by glucocorticoids (inflammation, stress, medical treatment). Estrogens decrease inflammation and reduce the glucocorticoid response. Low estrogen (infancy, menopause) again allow the predominance of glucocorticoids and the manifestation of the metabolic syndrome. It is postulated that the equilibrium between sex hormones and glucocorticoids may be a critical element in the timing of the manifestation of metabolic syndrome-related pathologies.

Relationship of androgens to body composition, energy and substrate metabolism and aerobic capacity in healthy, young women

OBJECTIVE

To evaluate the role of physiologic levels of androgens and their precursors in the regulation of body composition, energy and substrate metabolism and aerobic capacity in healthy, cycling, premenopausal women.

EXPERIMENTAL

We evaluated 30 young (27±1 year) premenopausal, non-obese (23±0.5 kg/m(2)), normally-cycling women, without clinical or chemical evidence of hyperandrogenism or hyperinsulinemia, for parameters of total and regional body composition, glucose tolerance, aerobic capacity and resting energy expenditure and substrate oxidation. Serum was assayed for androgens and androgen precursors by techniques optimized to assess the low androgen levels in this population.

RESULTS

Higher serum testosterone levels correlated with greater fat mass (r=0.377; p=0.04), but not abdominal adiposity or other metabolic/physiologic variables. Additionally, dehydroepiandrosterone (DHEA) was negatively related to visceral fat content (r=-0.569; p=0.02). Other serum androgens did not correlate with total or regional adiposity, skeletal muscle mass, aerobic capacity, glucose tolerance, or resting energy and substrate metabolism.

CONCLUSION

In this group of non-obese, premenopausal women with no clinical or chemical evidence of hyperandrogenemia, serum testosterone levels were positively related with fat mass, but not with abdominal adiposity; whereas, DHEA was negatively related to visceral adiposity. Our data suggest that within the normal physiologic range, testosterone is a predictor of overall adiposity, but that this effect does not appear to be associated with concomitant alterations in resting energy or substrate metabolism that could predispose to weight gain.

Role of DHEA-S on body fat distribution: gender- and depot-specific stimulation of adipose tissue lipolysis

The objective of this work was to study the possible impact of DHEA-S on body fat distribution and the specific action of the hormone on lipolysis from visceral and subcutaneous human adipose tissue. First, a clinical evaluation was performed in 84 obese patients (29 men, 55 women), measuring serum DHEA-S, computed tomography (CT) anthropometric parameters of abdominal fat distribution. In a second experiment, subcutaneous and visceral adipose tissue samples were obtained from 20 obese patients (10 men, 10 women) and cultured in vitro under stimulation with DHEA-S to further assess a possible effect of this hormone on adipose tissue lipolysis. Serum DHEA-S was inversely and specifically associated with visceral fat area (VA) as assessed by CT in men and with waist-to-hip ratio in women. In vitro, DHEA-S increased lipolysis in women's subcutaneous adipose tissue at 2 h, while in men, the effect was evident in visceral tissue and after 24 h of treatment. In conclusion, DHEA-S contributes to gender-related differences in body fat distribution probably by a differential lipolytic action. We have demonstrated for the first time in vitro that DHEA-S stimulates lipolysis preferably in subcutaneous fat in women and in visceral fat in men.

Effect of dehydroepiandrosterone on protein and fat digestibility, body protein and muscular composition in high-fat-diet-fed old rats

The main objective of the present study was to examine the effects of dehydroepiandrosterone (DHEA) on the digestive efficiency of dietary protein and fat. Second, we analysed the specific changes in muscle composition induced by the hormone. DHEA was given in the diet (0·5 %, w/w) to 75-week-old, high-fat-fed Sprague–Dawley rats (n11) for 13 weeks; age- and weight-matched rats fed on the same diet without DHEA supplementation were used as controls (n10). To determine dietary protein and fat apparent digestibility coefficients, 1-week 24 h faecal depositions were collected. In parallel, urine N was assessed. These assays were performed twice, in the short term (2-week treatment) and in the long term (13-week treatment). Body and gastrocnemius muscle compositions were also analysed. The present results show that DHEA decreased energy intake, body weight, body fat, adipocyte size and number (P < 0·001). The feed efficiency ratio indicates that DHEA-treated rats were less efficient in transforming nutrients fed into their own biomass. Also, a short-term reduction in protein digestibility (P < 0·05) and in body-protein degradation (P < 0·01) was found in DHEA-treated rats, resulting in an increased content of body protein (P < 0·05). Gastrocnemius muscles were smaller, as a result of fat (P < 0·05) but not protein reduction. In conclusion, we confirm the slimming effect of DHEA and, for the first time, we demonstrate that DHEA has an effect at the digestive level. The anti-obesity properties of DHEA could be related to a reduction in protein digestibility in the short term and a protective effect on body protein with a selective mass loss from body fat.

Fat tissue metabolism and adrenal steroid secretion

Obesity has reached epidemic proportions in Western societies, contributing to metabolic diseases, hypertension, and vascular diseases. White adipose tissue has traditionally been regarded merely as lipid, and consequently, as energy storage. However, recent data revealed the importance of adipose tissue as a highly active endocrine organ and its involvement in the body's metabolism and homeostasis. Obesity is associated with several endocrine disorders, including adrenocortical malfunction. Because of the central role of adrenal function in the body's homeostasis, adrenal malfunction is important in the development of other obesity-related abnormalities. Therefore, in this short review, we summarize recent data on obesity-induced changes in adrenocortical mineralocorticoid, glucocorticoid, and androgen secretions and their consequences for metabolism.

Effect of two modes of antiandrogen treatment on insulin sensitivity and serum leptin in women with PCOS

Androgens are suggested to interact with leptin production and with insulin sensitivity in both polycystic ovary syndrome (PCOS) and obesity. The aim of the study was to follow these interactions along with two forms of antiandrogen treatment. Twenty women with PCOS were treated with ethinylestradiol and high dose of cyproteroneacetate (EE-CA) and 8 with the gonadotrophin-releasing hormone (GnRH) analogue goserelin for 6 months. The patients were divided into a low and a high body weight group and compared with a group of overweight women without PCOS. Both treatments resulted in a significant reduction of free testosterone but the concentration of leptin remained unchanged. EECA treatment resulted in deterioration and GnRH in improvement of insulin sensitivity. Serum leptin correlated only with body weight and body fat. It is concluded that leptin levels do not adequately reflect changes in insulin sensitivity or androgen levels after short-term antiandrogen or antigonadotropin treatment.

Early carotid atherosclerosis in normotensive severe obese premenopausal women with low DHEA(S)

The aim of this study was to investigate the direct involvement of hyperinsulinaemia, DHEA and DHEA-S [DHEA(S)] in severe obesity in early carotid atherosclerosis, measured as intima-media thickness (IMT). Seventeen normotensive premenopausal women with very high BMI (43.5 +/- 1.6 kg/m2) were recruited for the study. Six women were also evaluated 12 months after laparoscopic adjustable silicone gastric banding (LASGB). Dietary intake, fasting plasma lipid profile, glycemic and insulinemic response to the OGTT, adrenal secretion, at baseline and after ACTH stimulation test, were measured. IMT, common carotid diameter (CD) and left ventricular mass index (LVMi) were measured by B-mode echotomography. All obese subjects showed higher fasting and stimulated insulin levels, but lower DHEA(S) levels than controls, showing a negative correlation between both fasting and stimulated insulin and DHEA(S), either at baseline or after ACTH testing. IMT was higher (p < 0.05) than controls, with a positive correlation with stimulated insulin (p < 0.05) and a strong negative correlation with DHEA(S) (p < 0.001). In a multiple linear regression analysis, insulin response to OGTT maintained an association with DHEA(S) independent of fasting insulin, while DHEA maintained the association with IMT independent of stimulated insulin (p < 0.0001). In the six patients evaluated 12 months after LASGB, fasting insulin levels decreased, while DHEA(S) levels increased (p < 0.05). In conclusion, an early cardiovascular involvement was detected in this group of severe obese with hyperinsulinaemia and low DHEA(S), even in the absence of other well known CVD risk factors.

Serum concentrations of dehydroepiandrosterone sulfate and leptin in obese patients with normal serum cholesterol

Normal (< 200 mg/dL) serum concentrations of cholesterol and a favorable ratio of cholesterol/high-density lipoprotein (HDL)-cholesterol are frequently seen in morbidly obese (body mass index [BMI] > 35 kg/m2) patients. Because it is unknown whether this subgroup is characterized by differences in other potential markers of cardiovascular disease, serum concentrations of dehydroepiandrosterone sulfate (DHEAS) and leptin were determined in 155 obese patients (BMI > 35 kg/m2, aged 20 to 50 years) with normal (n = 72) or with elevated (n = 83) total serum cholesterol. We found that seemingly negative marginal correlations between serum concentrations of DHEAS and cholesterol, as well as between DHEAS and the ratio cholesterol/HDL-cholesterol, were not any more apparent after correction for age, sex, and BMI. A negative correlation between serum leptin concentrations and the ratio cholesterol/HDL-cholesterol persisted after correction for age, sex, and BMI. In morbid obesity, there appears to be an association between serum concentrations of leptin and a more favorable lipid profile, whereas there is no direct interrelation between serum concentrations of cholesterol and DHEAS.

Serum adrenal androgens in women with primary operable breast cancer and their relationship with age and body mass index

Several studies have found elevated levels of adrenal androgens in postmenopausal women and depressed levels in premenopausal women with breast cancer, suggesting a role for adrenal androgens in the aetiology of breast cancer. We have measured serum dehydroepiandrosterone sulphate and androstenedione in 81 women with primary operable breast cancer and 62 age-matched controls. Results showed that serum levels of both adrenal androgens fell significantly with age in women with breast cancer (P=0.003). However, no relationship was observed between serum adrenal androgen levels and body mass index in either women with breast cancer or controls. Dehydroepiandrosterone sulphate levels were elevated in postmenopausal women with breast cancer compared to controls, and this was not due to preoperative stress. No differences were observed in androstenedione levels between premenopausal or postmenopausal women with breast cancer and controls, nor were dehydroepiandrostenedione sulphate levels significantly different between premenopausal women with breast cancer and controls. These results suggest that dehydroepiandrosterone sulphate has a role in the aetiology of postmenopausal breast cancer.

[Comparative study of the type of obesity in pre- and postmenopausal women: Relationship with fat cell data, fatty acid composition and endocrine, metabolic, nutritional and psychological variables]

BACKGROUND

The weight increase that many women experience during menopause may be the result of ageing. However, the precise factors inducing obesity during this period remain to be identified. The object of this study was to determine the type of obesity in a group of women along with its distinctive features, if any, as a function of the menopause stage.

PATIENTS AND METHOD

The sample consisted of 55 women (22 premenopausal and 33 postmenopausal) with grade I and II obesity. Distribution of body fat, composition of the adipose tissue, size and number of adipocytes, lipidic and hormonal profile as well as nutritional and psychological aspects were all taken into account.

RESULTS

Postmenopausal women had an android distribution of fat, whereas it was gynoid in premenopausal women. The adipose tissue showed different cell characteristics, the number of fat cells and content of saturated fatty acids (myristic and palmitic) being significantly lower in the postmenopausal group. Menopause was associated with an increase in plasmatic lipids and a decrease in the levels of certain hormones (dehydroepiandrosterone-sulphate and insulin). Postmenopausal women tended to have healthier eating habits than premenopausal women, with a significantly lower fat intake but higher carbohydrate and fibre intakes. However, the degree of physical activity was lower than in premenopausal women.

CONCLUSIONS

The type of obesity differs as a function of the menopausal status, a finding that should be taken into account when establishing a dietetic treatment.

Physiological levels and action of dehydroepiandrosterone in Yucatan miniature swine

The biological role of dehydroepiandrosterone (DHEA) and its less active sulphated conjugate DHEAS was investigated in two experiments using Yucatan miniature swine. In experiment 1, plasma levels of both DHEA(S) among males were greater than female pigs that ranged in age from 0.3 to 84 mo old (P < 0.0001). In males, DHEA(S) were related inversely to serum triglycerides; DHEA was positively related to triglycerides in females (P < 0.01). In experiment 2, four 2-yr old male pigs, used as their own control, showed a 5% decrease in body weight, 11% increase in energy expenditure, 88% increase in lipid, and 100% decrease in glucose utilization (P < 0.0001) in response to DHEA vs. placebo treatments when adjusted for body weight. Plasma DHEA(S) were not different between treatment conditions. Glucose tolerance and plasma insulin levels were not different from controls. In vivo response to norepinephrine indicated beta-adrenergic sensitivity was altered by DHEA. Present findings suggest DHEA and/or its hormone products are important in modulating energy expenditure and lipid utilization for energy in male animals. The role of DHEA in energy metabolism and the difference between sexes warrant further investigation.

Increased visceral adipose tissue is associated with increased circulating insulin and decreased sex hormone binding globulin levels in massively obese adolescent girls

The current study was designed to examine the relationship between body fat distribution, as evaluated by anthropometry and magnetic resonance imaging (MRI), and circulating insulin, sex hormone and SHBG levels in obese adolescent girls. Twenty-nine obese adolescent girls, aged 12.6-16.9 years with a mean BMI of 30.51+/-1.86 participated in this study. All girls had breast stage B4-5 and pubic hair stage P4-5. Percent obesity and BMI as indices of being overweight were calculated; the waist-to-hip ratio (WHR) and the waist-to-thigh ratio (WTR) were calculated to obtain two anthropometric indices for the pattern of body fat distribution. The areas of visceral (VAT) and subcutaneous adipose tissue (SAT) were evaluated by MRI at the L4-L5 level. Serum concentrations of total T, DHEAS, 17beta-estradiol, progesterone and SHBG were measured. Plasma glucose and insulin concentrations were evaluated during an oral glucose tolerance test. WHR was the only anthropometric parameter that was significantly associated with the area of VAT. Insulin level showed correlation with both WHR and the area of VAT; no correlation was found between insulin levels and WTR. Both WHR and VAT were negatively correlated with serum DHEAS level and positively correlated with T level. There were strong negative correlations between serum SHBG level and the area of VAT and WHR. Inverse correlation was found between serum SHBG level and insulin. Serum 17beta-estradiol and progesterone levels showed no significant correlation with all the patterns of body fat distribution. SAT was not significantly correlated with both anthropometric parameters and any of the sex hormones evaluated. We can draw two main conclusions. Firstly, in massively obese adolescent girls, the WHR seems to be a good indicator for the accumulation of VAT, and abdominal obesity, rather than adiposity per se, appears to be related to biochemical complications. Secondly, increased upper body adiposity and, in particular, the intra-abdominal fat area are associated with increased insulin levels in massively obese adolescent girls. The associated reductions in SHBG and DHEAS levels represent an early general risk factor for the development of metabolic and cardiovascular diseases in this population, as previously described for obese adult women.

Endocrine, metabolic and nutritional factors in obesity and their relative significance as studied by factor analysis

OBJECTIVE

To evaluate different aspects of obesity, such as body fat distribution, plasma hormone and lipid profiles, adipose tissue composition and dietary intake in an obese population in order to identify the most important factors that contribute to obesity.

DESIGN

Eighty-five obese subjects, 30 men and 55 women (age, 30-70 y; body mass index (BMI), 27-35 kg/m2), were studied using anthropometric measurements, computed tomography, adipose tissue composition, serum hormone and lipid profiles and nutritional evaluations. To determine to what extent individual factors contributed to the general process of obesity, the data were subjected to a factor analysis.

RESULTS

Three patterns of anthropometric and computed tomography data emerged that accounted for 69% of the variance. Factor 1 defined abdominal obesity and explained 30% of the total variance, factor 2 (gynoid obesity) accounted for 26%; and factor 3 (subcutaneous fat) explained 13% of the total variance. When other factors associated with obesity, such as lipid profile, hormonal profile and fat composition, were introduced, obesity itself, especially abdominal obesity, remained the principal factor, accounting for 23% of total variability. All factors were of secondary importance when dietary characteristics were introduced. In the overall factor analysis, more than 40% of the variability in obesity was related to dietary habits, particularly fat intake, followed by energy and saturated fatty acids intake.

CONCLUSION

Even though obesity is a multifactorial phenomenon, the results suggest that dietary intake, especially fat intake, is the most important factor contributing to obesity. Secondary factors include endocrine and metabolic factors.

Adrenal responsiveness to high, low and very low ACTH 1-24 doses in obesity

OBJECTIVE

To investigate adrenal activity in visceral obesity in which adrenal hyperactivity has been hypothesized. This could reflect hypothalamus-pituitary alterations leading to slight hyperfunction of the adrenal. Primary adrenal hypersensitivity to ACTH drive in obesity has also been suggested. However, it has also been reported that dehydroepiondrosterone (DHEA) levels in obesity are reduced and it has been hypothesized that this could play a role in the increased cardiovascular risk in obese patients.

SUBJECTS

We have studied seven obese women with visceral adiposity (OB, age: 33.6+/-3.3 years, BMI: 33.8+/-1.3 kg/m2, WHR: 0.88+/-0.01). The results in OB were compared with those recorded in a group of age-matched normal women (NS, age: 30+/-1.3 years, BMI: 19.9+/-0.4 kg/m2, WHR: 0.76+/-0.02).

METHODS

We have studied the cortisol (F), aldosterone (A) and DHEA responses to ACTH 1-24 administered at low (LD, 0.5 microg/m2) or very low (VLD, 0.125 microg/m2) dose followed by a second challenge with supramaximal dose (HD, 250 microg).

RESULTS

Basal F, A and DHEA levels in OB were similar to those in NS. The peak F responses to ACTH were dose-related in both groups. At each dose the F peaks in OB (VLD: 495.6+/-43.9 nmol/l, HD: 722.3+/-67.7 nmol/l; LD: 519.2+/-46.0 nmol/l, HD: 729.6+/-44.7 nmol/l) were similar to those in NS (VLD: 556.7+/-45.9 nmol/l, HD: 704.8+/-20.7 nmol/l; LD: 511.8+/-22.8 nmol/l, HD: 726.7+/-26.5 nmol/l). The peak A responses to ACTH were dose-related in both groups. At each dose, the A peaks in OB (VLD: 0.55+/-0.03 pmol/l, HD: 0.79+/-0.09 pmol/l; LD: 0.63+/-0.04 pmol/l, HD: 0.78+/-0.09 pmol/l) were similar to those in NS (VLD: 0.8+/-0.10 pmol/l, HD: 0.86+/-0.09 pmol/l; LD: 0.8+/-0.10 pmol/l, HD: 0.95+/-0.12 pmol/l). The peak DHEA responses to ACTH were dose-related in both groups. At each dose the DHEA peaks in OB (VLD: 58.6+/-13.3 nmol/l, HD: 61.9+/-13.1 nmol/l; LD: 55.18+/-6.4 nmol/l, HD: 72.3+/-9.8 nmol/l) were similar to those in NS (VLD: 54.3+/-8.2 nmol/l, HD: 57.8+/-8.2 nmol/l; LD: 42.2+/-3.7 nmol/l, HD: 56.9+/-4.3 nmol/l).

CONCLUSIONS

This study shows that the cortisol, aldosterone and dehydroepiondrosterone responses to high, low and very low ACTH doses in obese women overlap with those in age-matched lean controls; these findings suggest normal sensitivity of the different zones of the adrenal cortex to ACTH in obesity.

Low serum testosterone level as a predictor of increased visceral fat in Japanese-American men

OBJECTIVE

To examine the association between baseline testosterone levels and changes in visceral adiposity in Japanese-American men.

DESIGN

Prospective observational study.

SUBJECTS

Second-generation Japanese-American males enrolled in a community-based population study.

MEASUREMENTS

At baseline, 110 men received a 75g oral glucose tolerance test (OGTT), and an assessment of body mass index (BMI); visceral adiposity measured as intra-abdominal fat area (IAF) using computed tomography (CT); fasting insulin and C-peptide levels; and total testosterone levels. IAF was re-measured after 7.5 y. Subcutaneous fat areas were also measured by CT in the abdomen, thorax and thigh. The total fat (TF) was calculated as the sum of IAF and total subcutaneous fat areas (SCF).

RESULTS

After 7.5y, IAF increased by a mean of 8.0 cm2 (95% CI: 0.8, 15.3). Baseline total testosterone was significantly correlated with change in IAF (r= -0.26, P= 0.006), but not to any appreciable degree with change in BMI, TF, or SCF. In a linear regression model with change in IAF as the dependent variable, baseline testosterone was significantly related to this outcome while adjusting for baseline IAF, SCF, BMI, age, diabetes mellitus status (OGTT by the WHO diagnostic criteria) and fasting C-peptide (regression coefficient for baseline testosterone [nmol/l] = -107.13, P = 0.003).

CONCLUSIONS

In this Japanese-American male cohort, lower baseline total testosterone independently predicts an increase in IAF. This would suggest that by predisposing to an increase in visceral adiposity, low levels of testosterone may increase the risk of type 2 diabetes mellitus.

Dehydroepiandrosterone and related steroids alter 3T3-L1 preadipocyte proliferation and differentiation

The purpose of the present study was to determine if the anti-adipogenic effects of dehydroepiandrosterone (DHEA) are mediated solely by DHEA or by one or more of its downstream metabolites. In Experiment 1, preconfluent proliferating cultures of 3T3-L1 preadipocytes were incubated for either 24 or 72 h with 0, 1, 5 or 25 microM DHEA, DHEA sulfate (DHEAS), testosterone, estrone and 17beta-estradiol. Pregnenolone, a precursor of DHEA(S), was also tested at these concentrations. After 24 h of incubation, DHEAS, 17beta-estradiol and estrone at the 1 microM level stimulated preadipocyte proliferation. In contrast, DHEA and 17beta-estradiol at the 25 microM level attenuated proliferation to a greater extent than all other steroids. After 72 h of incubation, DHEA and 17beta-estradiol at the 25 microM level attenuated proliferation to a greater extent than all other steroids. In Experiment 2, post-confluent cultures of differentiating 3T3-L1 preadipocytes were incubated for 6 days with 0, 5, 30, or 60 microM levels of these steroids. Preadipocyte differentiation, as assessed by lipid content and glycerol-3-phosphate dehydrogenase activity, decreased markedly when treated with 30 and 60 microM DHEA, 17beta-estradiol, estrone and pregnenolone. In contrast, DHEAS had no impact on preadipocyte proliferation or differentiation. These results suggest that the anti-adipogenic actions of DHEA in adipose tissue may be mediated, in part, by one or more of its distal metabolites, including 17beta-estradiol.

Relationships between dehydroepiandrosterone-sulphate and anthropometric, metabolic and hormonal variables in a large cohort of obese women

OBJECTIVE

The aim of the present study was to measure dehydroepiandrosterone-sulphate (DHEA-S) levels in obesity and assess the relationships between DHEA-S and anthropometric, metabolic and hormonal variables.

SUBJECTS AND METHODS

We evaluated the serum DHEA-S levels in 217 obese but otherwise normal female subjects (age (mean +/- SEM): 39.4 +/- 0.9, range 18-67 years, body mass index (BMI) = 36.1 +/- 0.4, range 27.1-57.1 kg/m2).

RESULTS

DHEA-S levels showed an age-dependent fall similar to that observed in normal women (n = 156, age 46.2 +/- 1.2, range 22-69 years, BMI < 25 kg/m2). Adjusting for age, obese women had mean DHEA-S levels higher than the control group (P < 0.02). In obese patients, DHEA-S levels were directly associated with serum testosterone, androstendione, IGF-I, fT3 levels and 24 h-urinary cortisol. On the other hand, DHEA-S levels were negatively associated with age, total cholesterol, triglycerides levels and systolic blood pressure. No correlation was found with BMI, waist:hip ratio, basal and post-OGTT insulin and glucose, free fatty acids, GH, PRL, fT4, TSH, SHBG levels or diastolic blood pressure. Multiple regression analysis indicated that in obese women, DHEA-S levels were associated negatively to age and positively to testosterone, androstendione and IGF-I levels and daily urinary cortisol. In a subgroup of 20 obese women, DHEA-S levels significantly (P < 0.001) fell after OGTT without any correlation with the insulin response.

CONCLUSIONS

The present results show that dehydroepiandrosterone-sulphate levels are not reduced in obesity, being slightly increased, particularly in young adulthood. Dehydroepiandrosterone-sulphate levels are positively and independently associated with androgen, 24-h urinary cortisol and IGF-I levels but do not seem associated with insulin levels or cardiovascular risk indices.

Effects of aging on dehydroepiandrosterone sulfate in relation to fasting insulin levels and body composition assessed by bioimpedance analysis

Insulin can inhibit dehydroepiandrosterone (DHEA) biosynthesis in humans, as suggested by several studies performed in induced or spontaneous hyperinsulinemia. The increased insulin resistance documented throughout aging, with its accompanying hyperinsulinemia, may contribute to the age-related decline in DHEA synthesis. The aim of this study was to assess if the aging-related differences in DHEA sulfate (DHEA-S) serum levels can be associated with differences in fasting insulin levels, as well as body composition. Two hundred fifty-two healthy subjects of both sexes aged 19 to 90 years with a body mass index (BMI) less than 30 (mean +/- SD, 23.5 +/- 2.4) were studied DHEA-S and insulin serum levels were determined by a radioimmunologic procedure; body composition was assessed by anthropometry (fat mass percentage [FM%] estimated from four skinfold thicknesses by Durnin and Womersley and Siri equations [FM%-SKF]) and by bioimpedance analysis (BIA) (FM% estimated by equations developed by Segal et al and Deurenberg et al for subjects < and > 62 years, respectively [FM%-BIA]). DHEA-S levels were significantly and inversely related to age in both sexes. No significant aging-related differences were found in fasting insulin levels, although a trend toward an increase was apparent in the women on simple regression analysis. No significant associations were found between DHEA-S and insulin levels. As for body composition, a positive relationship to age was apparent for FM%-SKF, FM%-BIA, and waist to hip ratio (WHR), whereas BMI and phase angle ([PA] a bioelectric parameter considered an index of the ratio between intracellular and extracellular water) were inversely related to age. Fasting insulin levels were positively related to FM% as estimated by both BIA and anthropometry, independently of age in both sexes; in addition, a positive correlation with WHR and with the subscapular to triceps skinfold thickness ratio (SS/TS) was found in men and women, respectively. No significant correlation was apparent between DHEA-S and body composition indices in men, whereas in women a slight negative correlation between DHEA-S and WHR was documented, and was still significant after adjustment for age and fasting insulin. Stepwise multiple regression analysis confirmed that DHEA-S levels are not related to fasting insulin, but are independently related to age and, in women only, to WHR. Our study suggests that the DHEA-S decline due to aging is independent of fasting insulin, at least in healthy, non-obese people. In addition, it is not related to the aging-dependent changes in body composition in terms of FM% and fat-free mass (FFM) percentage (FFM%). Only in women could changes in fat distribution be slightly associated with DHEA-S decline, although such a relation cannot be accounted for by changes in insulin levels.

Dehydroepiandrosterone in morbidly obese adolescents: effects on weight, body composition, lipids, and insulin resistance

The hormone dehydroepiandrosterone (DHEA) has been reported to have beneficial effects on obesity, diabetes mellitus, and serum lipids in animal studies, but results in human studies are less clear. We conducted a randomized double-blind placebo-controlled trial to determine the effects of DHEA treatment on obesity and related physiologic conditions in adolescents and young adults. In this 10-week study, 13 morbidly obese subjects received a placebo for 2 weeks. After this run-in period, patients were randomized, with seven subjects (mean age, 15.5 years; body mass index [BMI, derived by dividing body weight in kilograms by height in meters squared], 48.2 +/- 9.7 [mean +/- SD]) receiving DHEA 40 mg sublingually twice daily for 8 weeks and six subjects (mean age, 18.0 years; BMI, 52.9 +/- 14) receiving placebo. Variables measured included body weight, body composition, resting metabolic rate (RMR), serum lipid levels, insulin sensitivity, and serum steroid levels. Treatment with DHEA resulted in a statistically significant increase in plasma DHEA and DHEA sulfate (DHEAS) concentrations (P < .01). Testosterone (T) levels were significantly increased in females who received DHEA. DHEA administration had no effect on body weight, sense of well-being, or any other measured variables. These findings suggest that DHEA 40 mg administered sublingually twice daily for 8 weeks has no positive effect on body weight, body composition, serum lipids, or insulin sensitivity in extremely obese adolescents and young adults.

Does collecting repeated blood samples from each subject improve the precision of estimated steroid hormone levels?

Measuring levels of steroid hormones in epidemiologic studies is difficult because pulsatile release can cause the levels of many hormones to vary markedly over short intervals, leading to a loss of precision in between-subject comparisons. Clinicians often control this variation by collecting several samples from each subject at defined intervals and pooling these samples for assay. The number of samples per subject that would adequately control such variation in an epidemiologic study has not been fully investigated. This study examines the effects of collecting 1, 2, or 3 samples per subject on the variances of 11 hormones and sex hormone binding globulin in men and 6 hormones in women. Three samples were collected at 30-minute intervals from each of 20 men and 59 women and were assayed separately. Variances that would be obtained in studies collecting one, two, or three samples per subject were then estimated. Collecting more than one sample substantially reduced the variances of several hormones in men but not in women.

Decreased androgen levels and obesity in men

Obesity in males is accompanied by a significant decrease in testosterone levels. This decrease is essentially a consequence of the decrease of the sex hormone binding hormone (SHBG) binding capacity, itself probably the consequence of the increased insulin levels. In moderate obesity, free testosterone levels are normal, however, and there does not exist a real hypogonadism. In massively obese males, on the other hand, there is real hypogonadotrophic hypogonadism, with decreased free testosterone levels. The latter are the consequence of functional alterations at the hypothalamopituitary pole of the testicular axis, characterized by a decreased amplitude of the LH pulses. The decrease in adrenal androgen (DHEAS) levels is moderate and although it has been claimed that the increased insulin levels may play a causal role, the exact mechanism of this decrease is still a matter of controversy.

The antiobesity effect of dehydroepiandrosterone in castrated or noncastrated obese Zucker male rats

Although antiobesity effect of dehydroepiandrosterone (DHEA) has been reported in rats, it remains unclear whether the effect is brought about by itself or mediated by sex steroids converted from DHEA in gonads. In the present study, to clarify this point, the effect of DHEA on growth in obese Zucker male rats was reevaluated under two conditions: with or without castration. Castration did not affect the pattern of growth curve of obese Zucker male rats. Three-months treatment of castrated Zucker rats with 0.3% DHEA in the diet resulted in dramatic decrease of body weight gain in comparison to DHEA-untreated and castrated rats. The degree of antiobesity effect of DHEA in castrated rats was almost same as that observed in non-castrated rats. These results suggest that DHEA exerted its antiobesity effect by itself rather than through conversion to testosterone in testis.

Dehydroepiandrosterone and body fat

Dehydroepiandrosterone sulfate (DHEA-S) is the most abundant circulating adrenal steroid in man, yet its physiologic role and that of its parent compound DHEA are unknown. Age-related decreases in DHEA in association with increases in obesity, insulin resistance, and atherosclerosis are well known. Recent investigations in lower mammals (which do not secrete DHEA) have suggested that DHEA (or its metabolites) may function as an antiobesity agent in these models of obesity independent of food intake. Proposed mechanisms for the decrease in fat mass and lower weight gain when DHEA is given orally include increases in futile cycling and peroxisomal beta-oxidation and decreases in de novo lipogenesis. Alterations in the availability of reducing equivalents for lipid synthesis do not appear to explain this decrease. Changes in pancreatic insulin secretion or insulin sensitivity may also be responsible for some of these effects. Studies in humans have failed to demonstrate a beneficial effect of DHEA on body composition or energy expenditure at either pharmacologic or physiologic replacement doses for 1-3 months. Administration of DHEA to men or women has also not been shown to alter insulin sensitivity as measured by the minimal model or the euglycemic clamp technique. The effect of DHEA on peroxisomal beta-oxidation and de novo lipogenesis is not known. We conclude that a significant role for DHEA in the pharmacologic treatment of human obesity is unlikely.

The relation of body size to plasma levels of estrogens and androgens in premenopausal women (Maryland, United States)

We analyzed data from a cross-sectional study of 107 premenopausal women to evaluate the relations of height, weight, and body mass index (BMI) with plasma hormone levels. Participants were 20- to 40-year old women residing in Maryland (United States), whose reported menstrual cycle lengths were not more than 35 days and whose measured weights for height were 85 to 130 percent of 'desirable' based on 1983 Metropolitan Life Insurance tables. Fasting blood specimens were collected on each of days 5-7, 12-15, and 21-23 of every participant's menstrual cycle and pooled to create follicular, midcycle, and luteal phase samples, respectively, for analysis. Adjusted for age, taller women had significantly higher follicular-phase plasma-estradiol levels (percent difference/cm = 1.5, 95 percent confidence interval [CI] = 0.3-2.7, and heavier women had significantly lower plasma sex-hormone binding globulin (SHBG) levels averaged across the menstrual cycle phases (percent difference/kg = -1.2; CI = -1.9-(-0.6). Body weight within the range studied, however, was not related significantly to the concentration of SHBG-bound estradiol during any phase of the menstrual cycle. The results of this cross-sectional study suggest a possible mechanism by which height may influence breast cancer risk.

Relationship between visceral fat, steroid hormones and insulin sensitivity in premenopausal obese women

OBJECTIVES

The relationships between visceral fat distribution, steroid hormones and peripheral insulin sensitivity were studied.

SETTING

All subjects were hospitalized in the Institute of Internal Medicine of the University of Verona, Italy.

SUBJECTS

Nineteen fertile obese women were studied with ages ranging from 18 to 53 years and body mass indexes ranging from 27.3 to 48.4.

INTERVENTION

Body fat distribution was evaluated by waist-to-hip circumference ratio and by computed tomography. The insulin tolerance test was used to evaluate peripheral insulin sensitivity. Glucose, insulin and C-peptide were measured in fasting conditions and during glucose load; total and free plasma testosterone and urinary cortisol excretion were also determined.

RESULTS

Significant correlations emerged between visceral adipose tissue and fasting glucose, insulin, and C-peptide, but not between visceral adipose tissue and total testosterone, free testosterone or urinary cortisol excretion. A negative correlation emerged between visceral adipose tissue and insulin sensitivity (r = -0.70; P < 0.01). No significant correlations were found between insulin sensitivity and age, body weight, body mass index, total adipose tissue, subcutaneous adipose tissue or waist-to-hip ratio. Total testosterone correlated with body weight, subcutaneous adipose tissue and total adipose tissue. Free testosterone and urinary cortisol excretion correlated positively with body weight, and negatively with age. No correlation was found between insulin sensitivity and total testosterone, free testosterone or urinary cortisol excretion. The correlation between visceral adipose tissue and insulin sensitivity remained significant even after adjusting for both age and the body mass index.

CONCLUSIONS

Our study shows that visceral fat is more closely associated with aberrations of insulin sensitivity than with obesity itself. Total testosterone, free testosterone and urinary cortisol excretion in our subjects do not seem to be associated with such aberrations.

Interrelationships between intraabdominal fat and total serum testosterone levels in obese women

Thirty-six women aged 18 to 52 years with body mass indexes (BMIs) between 27 and 52 were studied. Visceral and subcutaneous fat areas and body fat were evaluated by computerized tomography with a single scan at the IV-V lumbar vertebra level. Glucose, insulin, and C-peptide levels were measured before and after a glucose load. Total and free serum testosterone and 24-hour urinary cortisol excretion were measured. A stepwise multiple regression equation showed the visceral to subcutaneous fat area ratio to be the most powerful predictor for glucose alterations both during fasting and after a glucose load, and showed BMI to be the most powerful predictor for insulin and C-peptide levels. Total serum testosterone, after matching for age and BMI, demonstrates a significant negative correlation with visceral fat area. We conclude that in obese women, as in men, intraabdominal fat negatively correlates with serum testosterone levels.

Relation between sex hormones and serum lipoprotein and lipoprotein(a) concentrations in premenopausal obese women

Lipoprotein(a) (Lp[a]) is generally considered to be a risk factor for the development of cardiovascular disease, but little is known about the possible influence of obesity on the circulating levels of this lipoprotein. The present study was undertaken to examine this aspect in 136 menstrually active women by comparing the serum concentrations of Lp(a) between 72 obese and 64 age-matched nonobese women. Since an adverse effect of androgens and a protective effect of estrogens have been described for plasma lipoprotein profiles in obese women, the relation between the circulating levels of Lp(a) and those of these other hormones was also investigated in obese patients. In addition, other lipoproteins, anthropometric parameters (body mass index and waist-to-hip ratio), and insulin were evaluated. The levels of Lp(a) were not significantly different (Mann-Whitney U test chi 2, 3.59; p = 0.0582 [NS]) between obese (rank sum, 5,367) and control (rank sum, 3,949) women; in addition, the percentage of patients with high Lp(a) levels (cutoff defined at 30 mg/dL) did not differ between the two groups (obese women, 30%; control, 21.8%; chi 2, 0.90; two-sided p = 0.341 [NS]). Moreover, no correlation was found between Lp(a) and body mass index. Lastly, when the Lp(a) prevalence odds ratio for obesity was examined by adjusting the levels of this lipoprotein for age, triglycerides, total cholesterol, and high density lipoprotein cholesterol, the probability value (0.88) was far from significant. In obese women, no correlation was found between the logarithmically transformed Lp(a) concentrations and all the other variables evaluated in the study. In conclusion, the present study shows that the circulating levels of Lp(a) are not influenced by body weight and cardiovascular risk factors commonly associated with obesity, such as enhanced androgenic activity, hyperinsulinemia, adverse lipoprotein profile, and abdominal fat accumulation.

Increased free testosterone but normal 5 alpha-reduced testosterone metabolites in obese premenopausal women

OBJECTIVE

The aim of the study was to investigate whether the absence of increased 5 alpha-reductase activity explained the absence of hirsutism in premenopausal obese women with increased free testosterone (FT) levels.

DESIGN

As in hyperandrogenicity there generally exists evidence for increased 5 alpha-reductase activity, we measured, as parameters of 5 alpha-reductase activity, plasma levels of 5 alpha-androstane-3 alpha,17 beta-diol glucuronide (ADG) and androsterone glucuronide (ADTG) as well as their precursor levels in obese women without hirsutism, obese hirsute women, non-obese hirsute women, and non-obese, non-hirsute women.

PATIENTS

Eighty-two premenopausal women (20-45 years old) were studied, in four age matched groups: 39 controls, 18 obese without hirsutism, 11 non-obese hirsute and 14 obese hirsute women.

MEASUREMENTS

Blood samples were taken between days 5 and 7 of the menstrual cycle. Steroid hormone levels were measured by radioimmunoassay. Free testosterone levels were measured by equilibrium dialysis.

RESULTS

Compared to controls, mean free testosterone levels were increased (P less than 0.01) in obese, obese hirsute and hirsute patients, whereas mean DHEAS levels were increased in hirsute and obese hirsute (P less than 0.01), but not in obese, women. Mean androstanediol glucuronide levels were markedly increased in hirsute and obese hirsute patients (P less than 0.01), but not in obese women. Plasma androsterone glucuronide levels were increased in hirsute (P less than 0.01), in the normal range in obese hirsute, and decreased in obese women (P less than 0.01).

CONCLUSIONS

These results show that, despite the presence of higher free testosterone levels, neither 5 alpha-reductase activity (as suggested by normal androstanediol glucuronide levels) nor adrenal androgen precursor levels (DHEAS) are increased in obese women without hirsutism.

Influence of free testosterone on antigen levels of plasminogen activator inhibitor-1 in premenopausal women with central obesity

Women with upper body obesity are at increased risk for cardiovascular disease (CVD). Several studies have demonstrated a reduced fibrinolytic activity in these patients, mainly due to an enhanced activity of plasminogen activator inhibitor-1 (PAI-1). Since an increase of androgenic activity is a feature of central obesity in women, the present study was aimed at evaluating the possibility of a relationship between androgens and PAI-1 (antigen and activity) in 20 premenopausal women, 10 with upper body obesity and 10 controls. In obese women, PAI-1 antigen showed a positive Pearson correlation with free testosterone (FT), insulin, c-peptide, triglycerides (TG), and waist to hip ratio (WHR) (P less than .01), whereas PAI-1 activity correlated positively only with insulin and WHR (P less than .01). In control women, PAI-1 antigen and activity were positively related only to TG (P less than .01). When we applied the multiple regression model with stepwise backward method to our data, both PAI-1 antigen and activity did not maintain any significant association. However, when the data from both the groups were pooled (n = 20), and PAI-1 antigen was considered as the dependent variable, body weight (Sig T = 0.0001), TG (Sig T = 0.0053), FT (Sig T = 0.013), and luteinizing hormone (LH) (Sig T = 0.0474) met the stepwise criteria, suggesting an independent effect of each of these parameters on PAI-1 antigen. On the other hand, when PAI-1 activity was tested as the dependent variable, only body weight maintained a significant relationship with this parameter (Sig T = 0.0006).(ABSTRACT TRUNCATED AT 250 WORDS)