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Abstracts

LE Magazine November 2006
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DHEA

Effects of dehydroepiandrosterone on gluconeogenic enzymes and glucose uptake in human hepatoma cell line, HepG2.

Dehydroepiandrosterone (DHEA), the most abundant human adrenal steroid, improves insulin sensitivity and obesity in human and model animals. In a previous study, we reported that orally administered DHEA suppresses the elevated activities of hepatic gluconeogenic enzymes like glucose-6-phosphatase (G6Pase) in C57BL/KsJ-db/db mice. However, the molecular mechanisms by which DHEA ameliorates insulin resistance are not clearly understood. In the present study, we cultured the human hepatoma cell line HepG2 with DHEA and measured the enzyme activity and protein expression of G6Pase to investigate the direct effect of DHEA on glucose metabolism in hepatocytes. DHEA significantly suppressed both the activity and protein expression of G6Pase. Moreover, DHEA decreased the gene expression of G6Pase and phosphoenolpyruvate carboxykinase, both of which were maximal at 1 microM DHEA, whereas the mRNA level of glucose-6-phosphate translocase was unchanged. Furthermore, DHEA enhanced 2-deoxyglucose uptake, although its effect was much smaller than that of insulin. These results suggest that DHEA may act at multiple steps in the regulation of glucose metabolism in the liver.

Endocr J. 2005 Dec;52(6):727-33

Effects of early-life stress on behavior and neurosteroid levels in the rat hypothalamus and entorhinal cortex.

Recent evidence support the hypothesis that exposure to stress or trauma during early childhood may disturb the formation of functional brain pathways, in particular, of the limbic circuits. We examined the effects of exposure to early life trauma (juvenile stress) on emotional and cognitive aspects of behavior in adulthood as well as on dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) levels in relevant brain regions. Quantitative assessment of the effects of exposure to juvenile stress was made 1 month post-stress, and obtained by measuring: emotional (utilizing an open field and a startle response tests) and cognitive (Morris water-maze task) functions, as well as neurosteroids concentration (DHEA and its sulfate ester, DHEAS) in the hypothalamus and entorhinal cortex. We report here that an exposure to juvenile stress led to elevated levels of anxiety 1 month post-stress. Moreover, in a spatial learning task, the juvenile stress group performed poorer than the control group. Finally, an exposure to juvenile stress increased DHEAS but not DHEA concentrations both in the hypothalamus and the entorhinal cortex. These findings indicate that an exposure to juvenile stress has long-lasting effects on behavior and DHEAS levels in the hypothalamus and the entorhinal cortex. These effects may be of relevance to our understanding of early life stress-related disorders such as PTSD and major depression.

Brain Res Bull. 2006 Feb 15;68(6):419-24

Placebo-controlled trial of dehydroepiandrosterone (DHEA) for treatment of nonmajor depression in patients with HIV/AIDS.

OBJECTIVE: Subsyndromal major depressive disorder is common among HIV-positive adults. This study was designed to assess the efficacy of dehydroepiandrosterone (DHEA) as a potential treatment. METHOD: One hundred forty-five patients with subsyndromal depression or dysthymia were randomly assigned to receive either DHEA or placebo; 90% (69 of 77) of the DHEA patients and 94% (64 of 68) of the placebo patients completed the 8-week trial. The primary measure of efficacy was a Clinical Global Impression improvement rating of 1 or 2 (much or very much improved) plus a final Hamilton Depression Rating Scale score <or=8. Outcome was assessed by using intent-to-treat analysis, followed by completer analysis. Safety was assessed by queries about side effects at every study visit plus measures of CD4 cell count and HIV RNA viral load at baseline and week 8. DHEA dosing was flexible (100-400 mg/day). RESULTS: On the basis of clinicians’ ratings, DHEA was superior in the intent-to-treat analysis, where the response rate was 56% (43 of 77) for the DHEA group versus 31% (21 of 68) for the placebo group. In the completer analysis, the response rate was 62% (43 of 69) for the DHEA group, compared to 33% (21 of 64) for the placebo patients. The number needed to treat was 4 on the basis of intent-to-treat data and 3.4 on the basis of completer data. Few adverse events were reported in either treatment group, and no significant changes in CD4 cell count or HIV RNA viral load were observed in either group. CONCLUSIONS: Nonmajor but persistent depression is common in patients with HIV/AIDS, and DHEA appears to be a useful treatment that is superior to placebo in reducing depressive symptoms. The low attrition rate in this group of physically ill patients, together with requests for extended open-label treatment, reflect high acceptance of this readily available intervention.

Am J Psychiatry. 2006 Jan;163(1):59-66

Androgen therapy in women.

Androgens in women either derive from direct ovarian production or from peripheral conversion of the adrenal sex steroid precursor, dehydroepiandrosterone, towards active androgens. Therefore, loss of adrenal or ovarian function, caused by Addison’s disease or consequent to bilateral oophorectomy, results in severe androgen deficiency, clinically often associated with a loss of libido and energy. Importantly, physiological menopause does not necessarily lead to androgen deficiency, as androgen synthesis in the ovaries may persist despite the decline in estrogen production. However, the definition of female androgen deficiency, as recently provided by the Princeton consensus statement, is not precise enough and may lead to over-diagnosis due to the high prevalence of its diagnostic criteria: androgen levels below or within the lower quartile of the normal range and concurrent sexual dysfunction. Importantly, physiological menopause is not necessarily associated with androgen deficiency and therefore does not routinely require androgen therapy. Current replacement options include transdermal testosterone administration or dehydroepiandrosterone treatment, both of which have been shown to result in significant improvements, in particular in libido and mood, while effects on body composition and muscular function are not well documented. It is important to keep in mind that the number of randomized controlled trials is still limited and that currently none of the available preparations is officially approved for use in women. Currently, androgen replacement should be reserved for women with severe androgen deficiency due to an established cause and matching clinical signs and symptoms.

Eur J Endocrinol. 2006 Jan;154(1):1-11

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.

Am J Physiol Endocrinol Metab. 2006 Feb;290(2):E234-42

Short-term dehydroepiandrosterone treatment increases platelet cGMP production in elderly male subjects.

OBJECTIVE: Several clinical and population-based studies suggest that dehydroepiandrosterone (DHEA) and its sulphate (DHEA-S) play a protective role against atherosclerosis and coronary artery disease in human. However, the mechanisms underlying this action are still unknown. It has recently been suggested that DHEA-S could delay atheroma formation through an increase in nitric oxide (NO) production. STUDY DESIGN AND METHODS: Twenty-four aged male subjects [age (mean +/- SEM): 65.4 +/- 0.7 year; range: 58.2-67.6 years] underwent a blinded placebo controlled study receiving DHEA (50 mg p.o. daily at bedtime) or placebo for 2 months. Platelet cyclic guanosine-monophosphate (cGMP) concentration (as marker of NO production) and serum levels of DHEA-S, DHEA, IGF-I, insulin, glucose, oestradiol (E(2)), testosterone, plasminogen activator inhibitor (PAI)-1 antigen (PAI-1 Ag), homocysteine and lipid profile were evaluated before and after the 2-month treatment with DHEA or placebo. RESULTS: At the baseline, all variables in the two groups were overlapping. All parameters were unchanged after treatment with placebo. Conversely, treatment with DHEA (a) increased (P < 0.001 vs. baseline) platelet cGMP (111.9 +/- 7.1 vs. 50.1 +/- 4.1 fmol/10(6) plts), DHEA-S (13.6 +/- 0.8 vs. 3.0 +/- 0.3 micromol/l), DHEA (23.6 +/- 1.7 vs. 15.3 +/- 1.4 nmol/l), testosterone (23.6 +/- 1.0 vs. 17.7 +/- 1.0 nmol/l) and E(2) (72.0 +/- 5.0 vs. 60.0 +/- 4.0 pmol/l); and (b) decreased (P < 0.05 vs. baseline) PAI-1 Ag (27.4 +/- 3.8 vs. 21.5 +/- 2.5 ng/ml) and low-density lipoprotein (LDL) cholesterol (3.4 +/- 0.2 vs. 3.0 +/- 0.2 mmol/l). IGF-I, insulin, glucose, triglycerides, total cholesterol, HDL cholesterol, HDL2 cholesterol, HDL3 cholesterol, apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB) and homocysteine levels were not modified by DHEA treatment. CONCLUSIONS: This study shows that short-term treatment with DHEA increased platelet cGMP production, a marker of NO production, in healthy elderly subjects. This effect is coupled with a decrease in PAI-1 and LDL cholesterol levels as well as an increase in testosterone and E(2) levels. These findings, therefore, suggest that chronic DHEA supplementation would exert antiatherogenic effects, particularly in elderly subjects who display low circulating levels of this hormone.

Clin Endocrinol (Oxf). 2006 Mar;64(3):260-4

Dehydroepiandrosterone inhibited the bone resorption through the upregulation of OPG/RANKL.

The plasma level of dehydroepiandrosterone (DHEA) decreases gradually along with aging. The beneficial effects of DHEA as an anti-aging steroid, such as the stimulatory effect on immune system, anti-diabetes mellitus, anti-atherosclerosis, anti-dementia, anti-obesity and anti-osteoporosis have been demonstrated in experiment both in vitro and in vivo. It is important to investigate the effective mechanism of DHEA in therapeutics for postmenopausal osteoporosis. Having isolated and cultured osteoblasts (OBs) and osteoclasts (OCs), we analysed the effect of DHEA on osteoblastic viability, regulation of DHEA on the expression of osteoprotegerin (OPG)/receptor activator of NF-kappaB ligand (RANKL) mRNA in OBs, and then observed the action of DHEA on bone resorption of OCs in the presence or absence of OBs. The results showed that DHEA improved viability of OBs within the concentration range of 0.01-1 microM, especially at the concentration of 0.1 microM. DHEA could apparently increase the ratio of OPG/RANKL mRNA in OBs. In the presence of OBs, DHEA could decrease the number and area of absorption lacuna of specula. We concluded, therefore, only in the presence of OBs, DHEA could inhibit the bone resorption of OCs, which may be mediated by OPG/RANKL of OBs.

Cell Mol Immunol. 2006 Feb;3(1):41-5

Role of androgens and DHEA in bone metabolism.

Androgens have a major role in the growth and the maintenance of both cancellous and cortical bone mass in men. Androgen receptor is expressed in osteoblasts, osteoclasts and bone marrow stromal cells. Androgens have been shown to regulate the expression and the activity of several cytokines and growth factors, and control the homeostasis in bones. Dehydroepiandrosterone (DHEA) has a protective effect against osteoporosis in women after menopause through the intracrine mechanism in osteoblasts, which DHEA is converted to estrogen through the aromatase activity.

Clin Calcium. 2006 Jan;16(1):61-6

Dehydroepiandrosterone increases beta-cell mass and improves the glucose-induced insulin secretion by pancreatic islets from aged rats.

The effect of dehydroepiandrosterone (DHEA) on pancreatic islet function of aged rats, an animal model with impaired glucose-induced insulin secretion, was investigated. The following parameters were examined: morphological analysis of endocrine pancreata by immunohistochemistry; protein levels of insulin receptor, IRS-1, IRS-2, PI 3-kinase, Akt-1, and Akt-2; and static insulin secretion in isolated pancreatic islets. Pancreatic islets from DHEA-treated rats showed an increased beta-cell mass accompanied by increased Akt-1 protein level but reduced IR, IRS-1, and IRS-2 protein levels and enhanced glucose-stimulated insulin secretion. The present results suggest that DHEA may be a promising drug to prevent diabetes during aging.

FEBS Lett. 2006 Jan 9;580(1):285-90

Relationship between serum sex steroids and Aging Male Symptoms score and International Index of Erectile Function.

OBJECTIVES: To determine the relationship between the total and subscale scores of the Aging Male Symptoms (AMS) and International Index of Erectile Function (IIEF) questionnaires, age, and serum sex steroids levels. METHODS: A total of 348 patients enrolled in the study answered the AMS and IIEF questionnaires. Hormonal analysis, including total testosterone, free testosterone (FT), estradiol (E2), and dehydroepiandrosterone-sulphate (DHEA-S) measurement, were performed. The patients with a total AMS score of 29 were considered to have aging male symptoms and the patients with an IIEF score of less than 26 were considered to have sexual dysfunction. RESULTS: Although DHEA-S levels were significantly lower and E2 levels were greater in the men with aging male symptoms according to the AMS, the DHEA-S and FT levels were significantly lower in the men with sexual dysfunction, as determined by the IIEF score. Serum DHEA-S and FT levels and age correlated significantly with the IIEF scores. The total AMS score correlated significantly only with age. Although serum total testosterone, FT, and DHEA-S levels correlated significantly with the andrologic symptoms of AMS, the serum E2 levels correlated with psychological symptoms of AMS. CONCLUSIONS: Although aging male symptoms and the effects of hormonal changes on these symptoms have been controversial, DHEA-S and E2 might play some important roles in the symptoms of aging men.

Urology. 2005 Sep;66(3):597-601

Endogenous sex hormones and metabolic syndrome in aging men.

BACKGROUND: Sex hormone levels in men change during aging. These changes may be associated with insulin sensitivity and the metabolic syndrome. METHODS: We studied the association between endogenous sex hormones and characteristics of the metabolic syndrome in 400 independently living men between 40 and 80 yr of age in a cross-sectional study. Serum concentrations of lipids, glucose, insulin, total testosterone (TT), SHBG, estradiol (E2), and dehydroepiandrosterone sulfate (DHEA-S) were measured. Bioavailable testosterone (BT) was calculated using TT and SHBG. Body height, weight, waist-hip circumference, blood pressure, and physical activity were assessed. Smoking and alcohol consumption was estimated from self-report. The metabolic syndrome was defined according to the National Cholesterol Education Program definition, and insulin sensitivity was calculated by use of the quantitative insulin sensitivity check index. RESULTS: Multiple logistic regression analyses showed an inverse relationship according to 1 sd increase for circulating TT [odds ratio (OR) = 0.43; 95% confidence interval (CI), 0.32-0.59], BT (OR = 0.62; 95% CI, 0.46-0.83), SHBG (OR = 0.46; 95% CI, 0.33-0.64), and DHEA-S (OR = 0.76; 95% CI, 0.56-1.02) with the metabolic syndrome. Each sd increase in E2 levels was not significantly associated with the metabolic syndrome (OR = 1.16; 95% CI, 0.92-1.45). Linear regression analyses showed that higher TT, BT, and SHBG levels were related to higher insulin sensitivity; beta-coefficients (95% CI) were 0.011 (0.008-0.015), 0.005 (0.001-0.009), and 0.013 (0.010-0.017), respectively, whereas no effects were found for DHEA-S and E2. Estimates were adjusted for age, smoking, alcohol consumption, and physical activity score. Further adjustment for insulin levels and body composition measurements attenuated the estimates, and the associations were similar in the group free of cardiovascular disease and diabetes. CONCLUSIONS: Higher testosterone and SHBG levels in aging males are independently associated with a higher insulin sensitivity and a reduced risk of the metabolic syndrome, independent of insulin levels and body composition measurements, suggesting that these hormones may protect against the development of metabolic syndrome.

J Clin Endocrinol Metab. 2005 May;90(5):2618-23

Effect of DHEA on abdominal fat and insulin action in elderly women and men: a randomized controlled trial.

CONTEXT: Dehydroepiandro-sterone (DHEA) administration has been shown to reduce accumulation of abdominal visceral fat and protect against insulin resistance in laboratory animals, but it is not known whether DHEA decreases abdominal obesity in humans. DHEA is widely available as a dietary supplement without a prescription. OBJECTIVE: To determine whether DHEA replacement therapy decreases abdominal fat and improves insulin action in elderly persons. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled trial conducted in a US university-based research center from June 2001 to February 2004. PARTICIPANTS: Fifty-six elderly persons (28 women and 28 men aged 71 [range, 65-78] years) with age-related decrease in DHEA level. INTERVENTION: Participants were randomly assigned to receive 50 mg/d of DHEA or matching placebo for 6 months. MAIN OUTCOME MEASURES: The primary outcome measures were 6-month change in visceral and subcutaneous abdominal fat measured by magnetic resonance imaging and glucose and insulin responses to an oral glucose tolerance test (OGTT). RESULTS: Of the 56 men and women enrolled, 52 underwent follow-up evaluations. Compliance with the intervention was 97% in the DHEA group and 95% in the placebo group. Based on intention-to-treat analyses, DHEA therapy compared with placebo induced significant decreases in visceral fat area (-13 cm2 vs +3 cm2, respectively; P = .001) and subcutaneous fat (-13 cm2 vs +2 cm2, P = .003). The insulin area under the curve (AUC) during the OGTT was significantly reduced after 6 months of DHEA therapy compared with placebo (-1119 muU/mL per 2 hours vs +818 muU/mL per 2 hours, P = .007). Despite the lower insulin levels, the glucose AUC was unchanged, resulting in a significant increase in an insulin sensitivity index in response to DHEA compared with placebo (+1.4 vs -0.7, P = .005). CONCLUSION: DHEA replacement could play a role in prevention and treatment of the metabolic syndrome associated with abdominal obesity.

JAMA. 2004 Nov 10;292(18):2243-8

Is dehydroepiandrosterone a hormone?

Dehydroepiandrosterone (DHEA) is not a hormone but it is a very important prohormone secreted in large amounts by the adrenals in humans and other primates, but not in lower species. It is secreted in larger quantities than cortisol and is present in the blood at concentrations only second to cholesterol. All the enzymes required to transform DHEA into androgens and/or estrogens are expressed in a cell-specific manner in a large series of peripheral target tissues, thus permitting all androgen-sensitive and estrogen-sensitive tissues to make locally and control the intracellular levels of sex steroids according to local needs. This new field of endocrinology has been called intracrinology. In women, after menopause, all estrogens and almost all androgens are made locally in peripheral tissues from DHEA which indirectly exerts effects, among others, on bone formation, adiposity, muscle, insulin and glucose metabolism, skin, libido and well-being. In men, where the secretion of androgens by the testicles continues for life, the contribution of DHEA to androgens has been best evaluated in the prostate where about 50% of androgens are made locally from DHEA. Such knowledge has led to the development of combined androgen blockade (CAB), a treatment which adds a pure anti-androgen to medical (GnRH agonist) or surgical castration in order to block the access of the androgens made locally to the androgen receptor. In fact, CAB has been the first treatment demonstrated to prolong life in advanced prostate cancer while recent data indicate that it can permit long-term control and probably cure in at least 90% of cases of localized prostate cancer. The new field of intracrinology or local formation of sex steroids from DHEA in target tissues has permitted major advances in the treatment of the two most frequent cancers, namely breast and prostate cancer, while its potential use as a physiological HRT could well provide a physiological balance of androgens and estrogens, thus offering exciting possibilities for women’s health at menopause.

J Endocrinol. 2005 Nov;187(2):169-96

Correlations between hormones, physical, and affective parameters in aging urologic outpatients.

OBJECTIVE: To determine the relationship between sex hormones, physical complaints, depression, sexuality, and life satisfaction in aging men. METHODS: 263 outpatients aged 40 years and above (M=56.2; 40-84 years) were recruited from 6 andrological outpatient departments in Germany to evaluate “aging male” symptoms. Subjects were assessed by standardised self-report questionnaires, physical, and endocrinological examination. RESULTS: Total and free testosterone as well as DHEA-S (dehydroepiandrosterone-sulfate) levels decreased significantly with age. SHBG (sex hormone binding globulin) and LH (luteinizing hormone) increased; estradiol remained unchanged. Inactivity, lower urinary tract symptoms, erectile and orgasmic dysfunction also increased significantly with age. A low testosterone level was significantly associated with a reduced motivation and a lack of sexual desire. In addition to reduced testosterone levels, a reduced motivation was also predicted by depression and an impaired physical self-concept. Reduced activity, erectile dysfunction, and low testosterone levels contributed significantly to the lack of sexual desire. CONCLUSIONS: Aging men are frequently afflicted with a wide range of physical complaints (e.g. fatigue, prostate symptoms), erectile and orgasmic dysfunction, reflected in a reduced physical self-concept. Assessment and treatment of age-related physical and affective alterations must consider their close interplay with hormonal and lifestyle variables.

Eur Urol. 2005 Jun;47(6):749-55

Steroid sulfatase inhibitors as novel additions to the antipsoriatic armamentarium.

Psoriasis is a clinical conundrum that affects an estimated 1-3% of the world’s population. The psoriatic disease process, characterized by a type 1 cytokine pattern, is supposed to be maintained by a continuing immune response in a “peripheral lymphoid tissue” that forms in lesional skin and is composed of T cells, dendritic cells, and vessels arranged like a T-dependent zone in lymph nodes. Dehydroepiandrosterone (DHEA), produced from dehydroepiandrosterone sulfate (DHEAS) through the enzymatic activity of DHEA-sulfatase, plays a pivotal role in the development of the type 1 immune response generated in peripheral lymphoid organs. Taken together, it could be reasoned that DHEA-sulfatase inhibitors may have utility in the treatment of psoriasis. Furthermore, the addition of DHEA-sulfatase inhibitors to calcipotriol, which encourages type 2 immune response, may provide an additive or synergistic inhibition of the type 1 immune response underlying psoriasis. It has been shown that topical application of cholesterol sulfate in the hairless mouse causes epidermal hyperkeratosis, which can be prevented by co-application of topical cholesterol. Therefore, as the inhibition of conversion of cholesterol sulfate to cholesterol can induce epidermal hyperkeratosis and may thus abbreviate the benefit obtained by inhibition of DHEAS to DHEA conversion, topical sulfatase inhibitors should preferably be co-applied with topical cholesterol, though it is also possible that the beneficial immunological effects of steroid sulfatase inhibitors outweigh their possible hyperkeratosis stimulation. Alternatively, the production of specific DHEA-sulfatase inhibitors can resolve the above concern. DHEA-sulfatase inhibitors may prove invaluable in the treatment of psoriasis.

Med Sci Monit. 2005 Mar;11(3):HY7-9

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