The effect of six months treatment with a 100 mg daily dose of dehydroepiandrosterone (DHEA) on circulating sex steroids, body composition and muscle strength in age-advanced men and women

Correlates of circulating androgens in mid-life women: the study of women's health across the nation

CONTEXT

Androgens influence sexual differentiation and behavior, body composition, and physical functioning in men, but their role in women is less well understood. Because circulating androgens decline with age, the use of androgen supplementation for women to improve health and well-being has been increasing.

OBJECTIVE

The aim of this study was to assess the association between androgens and a variety of end points thought to be affected by androgens.

DESIGN

In a community-based baseline cohort of women aged 42-52 yr from the Study of Women's Health Across the Nation, we measured circulating testosterone (T), dehydroepiandrosterone sulfate, and SHBG, and calculated a free androgen index (FAI) in 2961 women.

MAIN OUTCOME MEASURES

Correlations of androgen measures with each other and with body mass index, waist circumference, and waist-hip ratio were computed, and odds ratios (OR) were estimated for the categorical outcomes of functional limitations, functional status, self-reported health, scores indicative of depressed mood, quality of life, sexual desire and arousal, and the presence of the metabolic syndrome.

RESULTS

Androgens, and particularly SHBG, were associated most strongly with body mass index, waist circumference, and waist-hip ratio. SHBG was associated prominently inversely with the metabolic syndrome (OR = 0.32; 95% confidence interval = 0.26-0.39), which was present in 17% of women at baseline. Dehydroepiandrosterone sulfate was associated modestly with functional status and self-reported health. T was associated minimally with increased sexual desire (OR = 1.09; 95% confidence interval = 1.00-1.18). The association of FAI with self-reported health and depressive symptomatology based on the Center for Epidemiologic Studies Depression Scale score was explained more by T than by SHBG, whereas the association of FAI with sexual arousal and metabolic syndrome was due more to SHBG than to T.

CONCLUSIONS

Circulating SHBG and androgens are most strongly associated with physical characteristics and the metabolic syndrome in women in this community-based cohort. Androgens are related weakly to physical functioning and other symptoms to which they commonly are attributed, such as sexual desire, sexual arousal, and well-being.

Supplementation with DHEA: Effect on Muscle Size, Strength, Quality of Life, and Lipids

OBJECTIVE

To evaluate the effects of combination estrogen/androgen therapy on muscle mass, strength and endurance, serum hormone and lipid profiles, and quality of life measures in postmenopausal women.

METHODS

Prospective, randomized, placebo-controlled pilot study at a tertiary care medical center. Fifty postmenopausal women were randomized to a 12-week course of (1) dehydroepiandrostenedione (DHEA) 50 mg daily, (2) conjugated equine estrogen (CEE) 0.625 mg daily, (3) DHEA 50 mg+CEE 0.625 mg daily, or (4) placebo. Main outcome measures of lower extremity muscle (calf) mass, functional muscle parameters, serum hormone and lipid levels, and quality of life (QOL) were obtained at baseline and after treatment. Statistical analysis compared percent change from baseline values and treatment differences among outcomes.

RESULTS

Significant increases in mean DHEA, DHEA sulfate (DHEA-S), testosterone, and androstenedione levels were noted with DHEA alone or combined DHEA/CEE treatments when compared with placebo. Compared with no hormone therapy, none of the supplemental hormone groups caused significant changes in muscle mass, muscle strength, muscle endurance, feelings of well-being, sleep, or sexual function.

CONCLUSIONS

Androgen replacement therapy, with DHEA, to menopausal women increases serum androgen levels without any appreciable effect on muscle cross-sectional area, muscle strength, muscle function, or improvement in health-related QOL.

Sex hormones and brain aging

Sex steroids exert pleiotropic effects in the nervous system, preserving neural function and promoting neuronal survival. Therefore, the age-related decrease in sex steroids may have a negative impact on neural function. Progesterone, testosterone and estradiol prevent neuronal loss in the central nervous system in different experimental animal models of neurodegeneration. Furthermore, progesterone and its reduced derivatives dihydroprogesterone and tetrahydroprogesterone reduce aging-associated morphological abnormalities of myelin and aging-associated myelin fiber loss in rat peripheral nerves. However, the results from hormone replacement studies in humans are thus far inconclusive. A possible alternative to hormonal replacement therapy is to increase local steroidogenesis by neural tissues, which express enzymes for steroid synthesis and metabolism. Proteins involved in the intramitochondrial trafficking of cholesterol, the first step in steroidogenesis, such as the peripheral-type benzodiazepine receptor and the steroidogenic acute regulatory protein, are up-regulated in the nervous system after injury. Furthermore, steroidogenic acute regulatory protein expression is increased in the brain of 24-month-old rats compared with young adult rats. This suggests that brain steroidogenesis may be modified in adaptation to neurodegenerative conditions and to the brain aging process. Furthermore, recent studies have shown that local formation of estradiol in the brain, by the enzyme aromatase, is neuroprotective. Therefore, steroidogenic acute regulatory protein, peripheral-type benzodiazepine receptor and aromatase are attractive pharmacological targets to promote neuroprotection in the aged brain.

Effect of dehydroepiandrosterone replacement on insulin sensitivity and lipids in hypoadrenal women

DHEA (dehydroepiandrosterone) replacement is not part of the current standard of care in hypoadrenal subjects. Animal studies have shown that DHEA administration prevents diabetes. To determine the physiological effect of DHEA replacement on insulin sensitivity in adrenal-deficient women, we performed a single-center, randomized, double-blind, placebo-controlled, crossover study in 28 hypoadrenal women (mean age 50.2 +/- 2.87 years) who received a single 50-mg dose of DHEA daily or placebo. After 12 weeks, insulin sensitivity was assessed using a hyperinsulinemic-euglycemic clamp. DHEA replacement significantly increased DHEA-S (sulfated ester of DHEA), bioavailable testosterone, and androstenedione and reduced sex hormone-binding globulin levels. Fasting plasma insulin and glucagon were lower with DHEA (42 +/- 4.94 vs. 53 +/- 6.58 pmol/l [P = 0.005] and 178 +/- 11.32 vs. 195.04 +/- 15 pmol/l [P = 0.02], respectively). The average amount of glucose needed to maintain similar blood glucose levels while infusing the same insulin dosages was higher during DHEA administration (358 +/- 24.7 vs. 320 +/- 24.6 mg/min; P < 0.05), whereas endogenous glucose production was similar. DHEA also reduced total cholesterol (P < 0.005), triglycerides (P < 0.011), LDL cholesterol (P < 0.05), and HDL cholesterol (P < 0.005). In conclusion, replacement therapy with 50 mg of DHEA for 12 weeks significantly increased insulin sensitivity in hypoadrenal women, thereby suggesting that DHEA replacement could have a potential impact in preventing type 2 diabetes.

Ageing affects the differentiation potential of human myoblasts

The ageing process causes a reduction in the regenerative potential of skeletal muscles eventually leading to diminished muscle strength. In this work we investigated if ageing affects the excitation-contraction coupling mechanism in human myotubes derived from human satellite cells, thereby contributing to the loss in muscle strength in the aged. To test this hypothesis, satellite cells from differently aged donors were differentiated in vitro and the maturation of the excitation-contraction mechanism was followed by the videoimaging technique monitoring the efficiency of such a mechanism in generating intracellular calcium transients. Our experiments showed a delay in the establishment of the excitation-contraction coupling mechanism depending on the age of the donor. Remarkably, the effect was reproducible in human satellite cells from a young donor aged in vitro, suggesting that the delayed functional maturation was strictly dependent on the number of satellite cell divisions and independent from the host environment.

Sarcopenia of aging and its metabolic impact

Sarcopenia contributes significantly to the morbidity, decrease in quality of life, and health care costs in the elderly. It is characterized by a decrease in muscle mass and strength, starting as early as the fourth decade of life in humans. Distinct muscle changes include a decrease in type 2 muscle fibers and a decrease in myosin heavy chains IIa and IIx mRNA levels. In addition, a decrease in whole body protein turnover, mixed muscle protein synthesis, myosin heavy chain synthesis, and mitochondrial protein synthesis have been reported. Different tissues and organs display different responses to aging, with more oxidative tissue generally having more age-related changes. Exercise has been shown to increase strength, aerobic capacity, and muscle protein synthesis, as well as to increase muscle mitochondrial enzyme activity in both young and older people; however, exercise does not reverse all age-related changes. The metabolic effects of sarcopenia include a decrease in resting metabolic rate secondary to decreased fat-free mass and decreased physical activity, leading to a higher prevalence of insulin resistance, type 2 diabetes mellitus, dyslipidemia, and hypertension. The way in which age-related changes in hormone levels affect muscle remains to be fully understood. The effect of replacing those hormones on sarcopenia has led to some conflicting results, but further investigations are ongoing.

Independent effect of endogenous dehydroepiandrosterone-sulphate levels and birth weight on bone turnover parameters in young adults

Data indicate that bone turnover is higher in young adults born with a low birth weight (LBW). Moreover, several data support the presence of altered adrenal hormone production in this population. The aim of our study was to investigate whether there is any connection between altered bone homeostasis and adrenal hormone levels. Bone mineral density (BMD), serum osteocalcin (OC), and urinary deoxypyridinoline (DPD) excretion were related to dehydroepiandrosterone-sulphate (DHEAS), cortisol, estradiol, testosterone, and sex-hormone binding globulin (SHBG) levels in 47 healthy young women (of those, 33 were LBW) and 65 healthy young men (of those, 49 were LBW). The age of the subjects was 19-21 years. BMD values were normal and did not correlate with any of the factors investigated. Cortisol did not have any independent effect on bone turnover parameters in either men or women. In women, birth weight, DHEAS levels, and free estradiol index were responsible for almost 50% (corrected r2= 0.45) of serum OC variability. Independent positive associations were observed between DHEAS and OC, and between DHEAS and DPD excretion. In men, birth weight and DHEAS levels together were responsible for more than one-third (corrected r(2) = 0.36) of the variability of serum OC. In contrast with women, DHEAS and OC were inversely correlated in men. Our results suggest that bone turnover depends on the subjects' birth weight. Moreover, DHEAS is also an independent determinant. The effect of DHEAS on bone turnover is different in women and men. DHEAS increases bone turnover in fertile women, while it decreases this in 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.

The aging male: testosterone deficiency and testosterone replacement. An up-date

The significance of the age-related decline of androgens remains unclear in terms of cardiovascular risk, mood and cognition, and prostatic health. Although much research has been undertaken in this area and men's health has received still more attention in the latest years, there are no data based on randomized controlled clinical studies in aging men investigating the long-term effects of androgen replacement therapy on various aspects of the cardiovascular system, the immune system, body composition, and the brain. In men receiving long-term androgen replacement therapy, the safety aspects regarding the prostate are also an area of clinical importance. In this paper we present an up-dated review of the experimental and clinical evidence of androgen deficiency and androgen replacement therapy on carbohydrate metabolism, on coagulation and fibrinolysis, inflammatory effects, effects on lipoprotein metabolism, direct arterial effects, effects on body composition, effects on cognitive function and mood, and prostatic effects. The evidence clearly shows that data for the most part are conflicting, with only very few randomized studies available.

Subnormal androgen levels in young female bone marrow transplant recipients with ovarian dysfunction, chronic GVHD and receiving glucocorticoid therapy

Ovarian function and sex hormone production with special focus on androgens (testosterone, androstenedione, dehydroepiandrosterone and its sulfate, DHEAS) was followed up during 1.5-20 (mean 9) years after bone marrow transplantation (BMT) in 24 female subjects aged 16-33 (mean 21) years at the last follow-up. All patients had received TBI and high-dose chemotherapy as the preparative regimen. A total of 24 female patients with conventionally treated pediatric hematologic malignancies served as controls. Four of 24 transplanted patients had spontaneous menstruation several years post transplantation, but in only one of them were serum FSH levels normal. Androgen levels of the BMT patients were lower than those of the conventionally treated patients. Subnormal testosterone levels were observed in 43% of BMT patients and subnormal DHEAS levels in 34% of BMT patients, the latter being a constant finding during glucocorticoid therapy for chronic GVHD (cGVHD). These results indicate that ovarian damage is a common late effect in patients transplanted at a young age, still having a seemingly normal pubertal development. Ovarian damage and cGVHD with glucocorticoid therapy are strongly associated with subnormal androgen levels. The clinical consequences of these changes and possible benefits of putative androgen replacement therapy remain to be elucidated.

Dehydroepiandrosterone and ageing

Dehydroepiandrosterone (DHEA) is the major steroid produced by the adrenal zona reticularis and, in contrast to cortisol and aldosterone, its secretion declines with ageing. This has generated major interest in its putative role as an 'anti-ageing' hormone. However, it is not clear that the age-associated, physiological decline in DHEA secretion represents a harmful deficiency. DHEA exhibits its action mainly by conversion to sex steroids. In addition, DHEA has neurosteroidal properties and may exhibit direct action via specific binding sites on endothelial cells. There is convincing evidence for beneficial effects of DHEA in patients with adrenal insufficiency and future research will hopefully elucidate its role in patients receiving pharmacological glucocorticoid treatment. However, in healthy elderly subjects, current evidence from randomised, controlled trials does not justify the use of DHEA, with no major beneficial effects reported and, in addition, potentially adverse effects on sex steroid-dependent tumour growth need to be considered.

Effects of dehydroepiandrosterone (DHEA) supplementation on hormonal, metabolic and behavioral status in patients with hypoadrenalism

Oral DHEA administration to patients with hypoadrenalism, in addition to glucocorticoid and mineralcorticoid replacement, may improve both well-being and hormonal/metabolic parameters. Twenty patients (13 men, 7 women, 26-76 yr, 11 with Addison's disease, 9 with central hypoadrenalism) were recruited in a placebo-controlled, randomized study. Hormone levels, carbohydrate and lipid parameters, bone metabolism, body composition and psychological parameters were evaluated at baseline and after treatment with DHEA 50 mg/day or placebo for 4 months. After 4 months of DHEA administration, serum DHEAS levels raised both in men (from 0.71+/-0.18 to 8.28+/-1.66 micropmol/l, p<0.005) and in women (from 0.25+/-0.07 to 5.65+/-1.93 micromol/l, p<0.05). Only in hypoadrenal women an increase in testosterone (T; from 0.4+/-0.1 to 1.45+/-0.26 nmol/l, p<0.05) and androstenedione (A; from 0.86+/-0.34 to 2.05+/-0.29 nmol/l, p<0.05) levels was observed. In men no significant modifications in T and 17-hydroxyprogesterone (17-OHP) levels were found, whereas serum SHBG significantly decreased. As far as the metabolic parameters are concerned, only in patients with Addison's disease a significant decrease in total cholesterol and in low-density lipoproteins after 4 months of DHEA administration was found. No changes in glucose metabolism and insulin sensitivity were observed. In basal conditions, mean serum osteocalcin (OC) was normal and significantly decreased after DHEA treatment. A significant reduction in body fat mass percentage (BF%) after DHEA administration was observed. As far as well-being is concerned, DHEA replacement did not cause any relevant variation of subjective health scales and sexuality in both sexes. Our study confirms that DHEA may be beneficial for female patients with hypoadrenalism, mainly in restoring androgen levels. Concerning the health status, more sensitive and specific instruments to measure the effects of DHEA treatment could be necessary.

Effect of DHEAS on skeletal muscle over the life span: the InCHIANTI study

BACKGROUND

It has been suggested that the reduced production of dehydroepiandrosterone sulfate (DHEAS) may be partially responsible for the decline of muscle strength and mass that often occurs with aging. However, this hypothesis has been only tested in small series of normal volunteers, with little consideration for potential confounders. Using data from a representative sample of 558 men (20-95 years) we tested the hypothesis that circulating DHEAS is independently associated with muscle strength and mass.

METHODS

Data are from InCHIANTI, an epidemiological study conducted in the Chianti geographic area (Tuscany, Italy). DHEAS serum levels were related to lower extremity muscle strength assessed by hand-held dynamometry and calf muscle area estimated from quantitative computerized tomography. Confounders included age, anthropometrics, physical activity, smoking, energy and alcohol intake, albumin, lipids, interleukin-6, comorbidity, depressive symptoms, and disability in activities of daily living.

RESULTS

In fully adjusted models predicting lower extremity muscle strength and calf muscle area, we found significant age*log DHEAS interactions, suggesting that the relationship between DHEAS levels and muscle parameters differs across the life span. In age-stratified models adjusted for confounders, serum DHEAS was an independent predictor of muscle strength (p <.02) and mass (p <.01), but only for men between 60 and 79 years of age. After adjusting these models for serum-free or bioavailable testosterone, results were unchanged.

CONCLUSIONS

In men aged 60-79 years, circulating DHEAS is an independent correlate of muscle strength and calf muscle area. The possible causal role of declining DHEAS in age-related sarcopenia should be further explored in longitudinal studies.

Androgen replacement therapy in women

OBJECTIVE

Review of literature with regard to androgen replacement therapy in women.

DESIGN

Review of the MEDLINE database and references from articles.

CONCLUSIONS

Androgens affect sexual function, bone health, muscle mass, body composition, mood, energy, and the sense of well-being. Androgen insufficiency clearly has been demonstrated in patients with hypopituitarism, adrenalectomy, oophorectomy, and in some women placed on oral estrogen therapy which increases sex hormone-binding globulin (SHBG) levels and lowers the free and bioavailable forms of T. Symptoms of androgen insufficiency in women may include a diminished sense of well-being, low mood, fatigue, and hypoactive sexual desire disorder with decreased libido, or decreased sexual receptivity and pleasure that causes a great deal of personal distress. The preponderance of evidence from clinical trials supports the correlation of decreased endogenous androgen levels with these symptoms and alleviation of many of the symptoms with the administration of T or, in some cases, DHEA. There are no Food and Drug Administration-approved androgen preparations on the market for treating androgen insufficiency in women. The safety profile of androgens in doses used for the treatment of hypoactive sexual desire disorder has been excellent with only mild acne and hirsutism being noted in a minority of patients.

Prevention and treatment of erectile dysfunction using lifestyle changes and dietary supplements: what works and what is worthless, part II

It seems naïve to believe that some plants or herbs do not contain specific compounds that could benefit patients with ED. Many supplements have not been investigated in a laboratory or clinical research setting before commercial sale, however,which creates a complex situation. If efficacy is or is not demonstrated through adequate research, then the benefit or lack thereof cannot be mentioned on the label. Furthermore, clinicians and the public cannot be made aware of which compounds or supplements are effective because no general standards for sale exist under the current guidelines. Dietary supplements have received a tremendous amount of publicity. The large and growing market for ED treatment seems to have contributed partly to the promotion of numerous supplements and their apparent benefits. Whether these dietary supplements have merit is questionable. Some supplements may produce results opposite to those advertised. Other supplements may be enjoying the benefits of the placebo effect. Because a placebo response of 25% to 50% has been recorded in clinical trials with effective agents, it is understandable that some supplements enjoy financial success despite the limited research espousing their use. If one to two of four individuals or one of three individuals who try a dietary supplement gain some benefit for their ED, the market for these supplements will remain extraordinary. On a larger scale, of 100,000 men who try a supplement, approximately 25,000 to 50,000 will claim some success. The challenge for clinicians is to discuss the placebo response properly and the need for good research before any intervention, especially supplements, can be advocated for general use. Table 2 summarizes some popular ED supplements and general conclusions that can be drawn from clinical investigations. Some dietary supplements may have an active ingredient that benefits patients with certain types of ED. An exciting area of future dietary supplement research is the ability of certain agents to have a synergistic effect with prescription agents for ED, thereby improving response rates in men that have failed approved ED therapy initially, especially with oral agents. Randomized clinical trials are the best method of determining which dietary supplements will become a part of conventional medicine. Therefore, more randomized trials for dietary supplements are needed so that they may have the opportunity to become a part of the mainstream milieu, which means that more funding needs to be made available for ED research. The coming years of research should bring enormous excitement and objectivity to this area of medicine.

The effect of circulating androgens on bone mineral density in postmenopausal women

BACKGROUND

Osteoporosis is a common problem in postmenopausal period. Recent studies have suggested that endogenous and exogenous androgens may influence the bone mineral density in women. There is limited data about the effect of circulating androgens on bone density in postmenopausal women.

AIM

The aim of this study was to evaluate the effect of circulating androgens of ovarian and adrenal origin on bone mineral density in postmenopausal women.

MATERIALS AND METHODS

This cross-sectional study included 178 postmenopausal women, who had never been treated with hormonal therapy or calciotropic agents. Serum free testosterone, dehydroepiandrosterone sulfate and androstenedione levels and their relationship with bone mass (dual X-ray absorptiometry) were evaluated.

RESULTS

Serum free testosterone and DHEAS levels were correlated positively with bone mineral density at lumbar spine and femoral neck (P < 0.001). However, stepwise linear regression analyses revealed a differential effect of androgens on bone density. Serum free testosterone was among the independent predictor of bone density at lumbar spine (trabecular bone), whereas serum DHEAS level was of bone density at femoral neck (cortical bone).

CONCLUSION

This study suggests that endogenous androgens are influential on bone density in postmenopausal women. However, regression analyses revealed a differential effect of androgens on different bone types.

Muscle tissue changes with aging

PURPOSE OF REVIEW

This review article focuses on the changes that occur in muscle with age, specifically the involuntary loss of muscle mass, strength and function, termed sarcopenia. Particular emphasis is given to the metabolic alterations that characterize sarcopenia, and to the potentially treatable causes of this condition, including age-related endocrine and nutritional changes, and inactivity.

RECENT FINDINGS

Recent data reported include those regarding the potential role of insulin resistance in the development of sarcopenia, the potential role of androgens and growth hormone in the treatment of this condition, the usefulness of exercise including both resistance and aerobic training to improve muscle growth and function, and, finally, the possible use of nutritional manipulations to improve muscle mass.

SUMMARY

Sarcopenia is likely a multifactorial condition that impairs physical function and predisposes to disability. It may be prevented or treated with lifestyle interventions and pharmacological treatment. Further long-term investigations are needed, however, to ascertain what type and combinations of interventions are the most efficacious in improving muscle mass and function in older people.

Long-term low-dose dehydroepiandrosterone replacement therapy in aging males with partial androgen deficiency

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) age-related withdrawal is very likely to be involved in the aging process and the onset of age-related diseases, giving rise to the question of whether preventing or compensating the decline of these steroids may have endocrine and clinical benefits. The aim of the present trial was to evaluate the endocrine, neuroendocrine and clinical consequences of a long-term (1 year), low-dose (25 mg/day) replacement therapy in a group of aging men who presented the clinical characteristics of partial androgen deficiency (PADAM). Circulating DHEA, DHEAS, androstenedione, total testosterone and free testosterone, dihydrotestosterone (DHT), progesterone, 17-hydroxyprogesterone, allopregnanolone, estrone, estradiol, sex hormone binding globulin (SHBG), cortisol, follicle stimulating hormone (FSH), luteinizing hormone (LH), growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels were evaluated monthly to assess the endocrine effects of the therapy, while beta-endorphin values were used as a marker of the neuroendocrine effects. A Kupperman questionnaire was performed to evaluate the subjective symptoms before and after treatment. The results showed a great modification of the endocrine profile; with the exception of cortisol levels, which remained unchanged, DHEA, DHEAS, androstenedione, total and free testosterone, DHT, progesterone, 17-hydroxyprogesterone, estrone, estradiol, GH, IGF-1 and beta-endorphin levels increased significantly with respect to baseline values, while FSH, LH and SHBG levels showed a significant decrease. The Kupperman score indicated a progressive improvement in mood, fatigue and joint pain. In conclusion, the present study demonstrates that 25 mg/day of DHEA is able to cause significant changes in the hormonal profile and clinical symptoms and can counteract the age-related decline of endocrine and neuroendocrine functions. Restoring DHEA levels to young adult values seems to benefit the age-related decline in physiological functions but, however promising, placebo-controlled trials are required to confirm these preliminary results.

The contribution of reactive oxygen species to sarcopenia and muscle ageing

Ageing is a complex process that in muscle in usually associated with a decrease in mass, strength, and velocity of contraction. One of the most striking effects of ageing on muscle is known as sarcopenia, a process that is the result of many cellular changes, such as a reduction in the number of motor units coupled with an increase in motor unit size, progressive denervation, decreased synthesis of myofibrillar components, atrophy due to disuse, accumulation of connective tissue, etc. It has been suggested that sarcopenia may be triggered by reactive oxygen species (ROS) that have accumulated throughout one's lifetime. ROS, which are generated by the addition of a single electron to the oxygen molecule, are formed in all tissues including muscle fibres and, especially, in the mitochondrial respiratory chain. Such reactive elements are usually quite harmful and result in oxidative stress that can damage other cellular components such as DNA, proteins, lipids, etc. resulting in further damage to the cells and tissues. As a consequence, the intra and intercellular membranes of the muscle fibers, in particular those of the Sarcoplasmic reticulum, may be modified and the Ca(2+) transport mechanism altered. During the ageing process ROS production may drastically increase because of an altered function of the respiratory chain and an insufficient functioning of the antioxidant cellular defences. How such an oxidative insult plays a role in the age-related decrease of muscle performance and mass has yet to be defined. What does have a clear role in the progression of sarcopenia is the significant reduction of the regenerative potential of muscle fibres. This reduction is due to a reduced pool of satellite cells that are usually recruited to replace damaged fibres and promote their regeneration. Exercise as a method to prevent or at least delay sarcopenia has been discussed in many scientific reports. While on the one hand, it seems clear that exercise is effective in reducing the loss of muscle mass, on the other it appears that physical activity increases both the mechanical damage and the accumulation of free radicals as a result of an increase in the aerobic metabolism of the muscles involved.

Steroid sulfatase gene variation and DHEA responsiveness to resistance exercise in MERET

Genetic influences and endurance exercise have been shown to alter circulating concentrations of dehydroepiandrosterone (DHEA) and its sulfated conjugate, DHEAS. We hypothesized that acute resistance exercise (RE) and training (RET) would increase DHEA steroids, and the magnitude of the increase would be influenced by a steroid sulfatase (STS) gene variation. Fasting blood samples were collected before and after the first ( S1) and last ( S30) session of a 10-wk RET program in 62 men and 58 women [age: 21.0 yr (2.4)]. Acute RE increased both DHEA [+2.8 (0.4), S1; +1.6 ng/ml (0.4), S30; P < 0.001] and DHEAS [+154 ( 24 ), S1; +166 ng/ml ( 15 ), S30; P < 0.001] and decreased DHEAS:DHEA [−27 ( 8 ), S1; −15 ( 7 ), S30; P < 0.01]. RET reduced resting DHEAS (−122 ng/ml, P < 0.01) and decreased DHEA response to RE (−50%, P < 0.05). Subjects with an STS “G” allele ( n = 36) had greater acute changes in DHEA [+4.4 (0.7) vs. +2.0 ng/ml (0.5), S1; +3.2 (0.6) vs. +1.0 ng/ml (0.4), S30; P < 0.01] and DHEAS:DHEA [−37 ( 11 ) vs. 5 ( 7 ), S30, P < 0.05] than those subjects with only an “A” allele ( n = 84). The observed increase in DHEA and DHEAS and decrease in DHEAS:DHEA suggest RE-induced STS activation which is influenced by the STS polymorphism.

Pharmacokinetics of dehydroepiandrosterone and its metabolites after long-term daily oral administration to healthy young men

OBJECTIVE

To determine the effects of dehydroepiandrosterone (DHEA) supplementation on the pharmacokinetics of DHEA and its metabolites and the reproductive axis of healthy young men.

DESIGN

A prospective, randomized, double-blind, placebo-controlled pharmacokinetic study.

SETTING

General Clinical Research Center and laboratories at the Keck School of Medicine of the University of Southern California, Los Angeles, California.

PATIENT(S)

Fourteen healthy men, ages 18-42 years.

INTERVENTION(S)

Daily oral administration of placebo (n = 5), 50 mg DHEA (n = 4), or 200 mg DHEA (n = 5) for 6 months. Blood samples were collected at frequent intervals on day 1 and at months 3 and 6 of treatment.

MAIN OUTCOME MEASURE(S)

Quantification of DHEA, DHEA sulfate (DHEAS), androstenedione, T, E(2), dihydrotestosterone (DHT), and 5alpha-androstane-3alpha-17beta-diol glucuronide (ADG). Physical examination, semen analysis, serum LH, FSH, prostate-specific antigen, and general chemistries were carried out.

RESULT(S)

Baseline DHEA, DHEAS, and ADG levels increased significantly from day 1 to months 3 and 6 in the DHEA treatment groups but not in the placebo group. No significant changes were observed in pharmacokinetic values. Clinical parameters were not affected.

CONCLUSION(S)

DHEA, DHEAS, and ADG increased significantly during 6 months of daily DHEA supplementation. Although the pharmacokinetics of DHEA and its metabolites are not altered, sustained baseline elevation of ADG, a distal DHT metabolite, raises concerns about the potential negative impact of DHEA supplementation on the prostate gland.

DHEAS as a new diagnostic tool

Dehydroepiandrosterone sulfate (DHEAS) is a 19-carbon steroid, situated along the steroid metabolic pathway. It is the most abundant circulating steroid hormone in the body and can be converted to either androgens or estrogens. Their physiological and pathological functions have not yet been fully identified. Serum DHEAS concentrations peak at around age 25 years and then decline steadily over the following decades. Due to its long half-life and high concentration in the blood, the levels of DHEAS remain the same 24 h a day. This makes DHEAS a very interesting new diagnostic tool for both scientific research and clinical diagnostics. Moreover, circulating concentrations of DHEAS can be changed by many factors, such as endogenous production, hormone supplementation, many kinds of drugs, and many types of disease states. As research moves forward to better understand the relationships of DHEAS with health and disease, it is essential that studies should be designed to control for the influence of many factors on serum DHEAS concentrations.

Anabolic Hormones in Aging Women: Effects of Supplementation vs. Physical Activity

Aging is associated with a decline in bone mass, muscle mass, strength, and physical function, and women are more likely to suffer from these physical changes than men. The model presented in this paper illustrates the age related changes in anabolic hormones and how this may partly explain the diminished physical function of older women. The model can also be used to identify potential sites of intervention that could delay the atrophy of the musculoskeletal system. Various pharmacological hormone therapies have been shown to be beneficial, but there may be health risks associated with their use. There is evidence that regular physical activity is related to higher levels of anabolic hormones in older persons, therefore exercise could be an alternative to drugs for slowing the age related changes in the endocrine system. However, some research suggests that the hormone response to exercise is blunted in older women. This lower hormonal response may not be a consequence of aging per se but instead may result from secondary characteristics of aging such as a decline in physical fitness and exercise intensity or changes in body composition. Further research is needed to determine whether exercise-induced increases in endogenous hormones have clinical significance in improving muscle or bone mass in aging women. Key words: hormone replacement therapy, exercise, sex steroids, growth hormone, IGF-I

Evidence that androgenic and estrogenic metabolites contribute to the effects of dehydroepiandrosterone on cognition in postmenopausal women

Prior studies of the effects of dehydroepiandrosterone (DHEA) on cognition have produced complex and inconsistent results. We hypothesize that these results may arise, in part, because of DHEA's metabolism into estrogens and androgens that produce opposing effects on cognition. Our study administered 50 mg of oral DHEA daily for 4 weeks in a placebo-controlled crossover design to six postmenopausal women. We measured blood levels of androgens (total testosterone, free testosterone, DHEA, DHEAS), estrogens (estradiol, estrone), and cognitive performance on recognition memory, perceptual identification, digit span memory, and visual attentional vigilance under both drug and placebo conditions. Multiple regression models incorporating the factors of age and body mass index (BMI) were used to ascertain the relation between sex steroids and cognitive performance. Our results demonstrated that estrogens produced a positive effect on recognition memory, while androgens produced a negative effect. This pattern reversed in perceptual identification with estrogens producing a negative effect and androgens producing a positive effect. In addition, BMI produced a negative effect on digit span memory, age produced a negative effect on perceptual identification, and androgens produced a negative effect on visual attentional vigilance. These results help, in part, to explain DHEA's complex effects on cognition. The diverse effects of sex steroids across tasks underscore the importance of identifying the specific cognitive mechanisms influenced by sex steroids and emphasizes that one should not expect sex steroids to produce homogeneous effects across cognitive tasks.

Effects of Resistance Training on Older Adults

Using an integrative approach, this review highlights the benefits of resistance training toward improvements in functional status, health and quality of life among older adults. Sarcopenia (i.e. muscle atrophy) and loss of strength are known to occur with age. While its aetiology is poorly understood, the multifactorial sequelae of sarcopenia are well documented and present a major public health concern to our aging population, as both the quality of life and the likelihood of age-associated declines in health status are influenced. These age-related declines in health include decreased energy expenditure at rest and during exercise, and increased body fat and its accompanying increased dyslipidaemia and reduced insulin sensitivity. Quality of life is affected by reduced strength and endurance and increased difficulty in being physically active. Strength and muscle mass are increased following resistance training in older adults through a poorly understood series of events that appears to involve the recruitment of satellite cells to support hypertrophy of mature myofibres. Muscle quality (strength relative to muscle mass) also increases with resistance training in older adults possibly for a number of reasons, including increased ability to neurally activate motor units and increased high-energy phosphate availability. Resistance training in older adults also increases power, reduces the difficulty of performing daily tasks, enhances energy expenditure and body composition, and promotes participation in spontaneous physical activity. Impairment in strength development may result when aerobic training is added to resistance training but can be avoided with training limited to 3 days/week.

Dehydroepiandrosterone as an inducer of mitochondrial permeability transition

This paper reports an investigation upon the effect of dehydroepiandrosterone (DHEA) on some mitochondrial membrane functions, such as electron transport, transmembrane electric gradient and calcium permeability. It was found that the hormone induced the efflux of accumulated matrix Ca(2+), inhibited Site I of the respiratory chain, as well as bringing about the collapse of the transmembrane potential, and mitochondrial swelling. Taking into account that cyclosporin A (CSA) inhibited Ca(2+) release and the collapse of the transmembrane potential, it is concluded that the hormone may induce the opening of a non-specific transmembrane pore. The mechanism of pore opening is ascribed to peroxidation of the membrane lipid bilayer. It should be mentioned that estrone, even at the concentration of 200 microM, failed to reproduce the behavior of dehydroepiandrosterone on mitochondrial functions.

Resting serum dehydroepiandrosterone sulfate level increases after 8-week resistance training among young females

This study examined changes among young females of resting serum dehydroepiandrosterone sulfate (DHEAS) concentration after an 8-week period of resistance training. Nineteen healthy untrained young females [training group: age 18.9 (0.3) years, n=10, control group: age 19.3 (1.0) years, n=9; mean (SD)] were recruited in this study. The training group participated in an 8-week resistance training program (2 days per week on nonconsecutive days). The control group did not involve in any resistance training or regular exercise during the study period. Muscular strength, anthropometry, and resting hormonal levels were measured before and after training in both groups. Serum concentrations of DHEAS, dehydroepiandrosterone (DHEA), testosterone and cortisol were measured by radioimmunoassay. Body mass (2.4%) and lean body mass (2.4%) were significantly increased in the training group ( P<0.05), but not in the control group. The training also significantly increased one-repetition maximum (1-RM) values ( P<0.05). In the training group, resting concentration of serum DHEAS significantly increased after training ( P<0.05). Percent change of DHEAS in the training group was greater than that of the control group ( P<0.05). In the training group, the change of DHEAS level was positively correlated with the change of lean body mass during the training ( r=0.61; P<0.05). Serum DHEA, testosterone and cortisol concentrations did not change in either group during the training. The dramatic increase of resting serum DHEAS concentration after training indicates that DHEAS might be an anabolic hormone marker of adaptation to resistance training among young females. Results are presented as mean (SD).

Interictal EEG discharges, reproductive hormones, and menstrual disorders in epilepsy

We evaluated reproductive endocrine function in women with unilateral temporolimbic epilepsy and normal control subjects to assess the effects of epilepsy, epilepsy laterality, and antiepileptic drug use on the cerebral regulation of hormonal secretion. The findings indicate that reproductive endocrine function differs between women with epilepsy and normal control subjects. Significant differences exist at all levels of the reproductive neuroendocrine axis, that is, hypothalamus, pituitary, and peripheral gland. Differences show significant relationships to the epilepsy itself as well as to medication use. Reproductive neuroendocrine changes occur in a stochastic manner such that the laterality of unilateral temporolimbic discharges is associated with predictable directional changes in hormonal secretion at all levels of the reproductive neuroendocrine axis. These directional changes are consistent with the finding that different reproductive disorders may develop in relation to left- and right-sided temporolimbic epilepsy. Hormonal changes can show close temporal relationship to the occurrence of interictal epileptiform discharges and may vary in relation to the laterality of the discharges. Antiepileptic drugs differ in their effects on reproductive hormone levels. There are notable differences between enzyme-inducing and noninducing drugs. Menstrual disorders are more common among women with interictal discharges as well as women with abnormal hormonal findings.

Dehydroepiandrosterone: is there a role for replacement?

Dehydroepiandrosterone (DHEA) and its sulfated ester are found in high concentrations in the plasma; however, their role in normal human physiology, other than as precursors for sex hormones, remains incompletely defined. Studies of rodent models have shown that these hormones have beneficial effects on a wide variety of conditions, such as diabetes, obesity, immune function, atherosclerosis, and many of the disorders associated with normal aging. However, rodents are not the best models to study the actions of these hormones because they have very little endogenous DHEA; thus, the doses given to these animals are usually suprapharmacological. Human studies have been performed to determine the potential beneficial effects of DHEA replacement in persons with low DHEA levels. Results have been conflicting. Human studies suggest a potential role for DHEA replacement in persons who have undergone adrenalectomy and possibly in the aging population. However, long-term studies assessing the benefits vs adverse effects must be done before DHEA replacement can be recommended.

Steroid hormones and neurosteroids in normal and pathological aging of the nervous system

Without medical progress, dementing diseases such as Alzheimer's disease will become one of the main causes of disability. Preventing or delaying them has thus become a real challenge for biomedical research. Steroids offer interesting therapeutical opportunities for promoting successful aging because of their pleiotropic effects in the nervous system: they regulate main neurotransmitter systems, promote the viability of neurons, play an important role in myelination and influence cognitive processes, in particular learning and memory. Preclinical research has provided evidence that the normally aging nervous system maintains some capacity for regeneration and that age-dependent changes in the nervous system and cognitive dysfunctions can be reversed to some extent by the administration of steroids. The aging nervous system also remains sensitive to the neuroprotective effects of steroids. In contrast to the large number of studies documenting beneficial effects of steroids on the nervous system in young and aged animals, the results from hormone replacement studies in the elderly are so far not conclusive. There is also little information concerning changes of steroid levels in the aging human brain. As steroids present in nervous tissues originate from the endocrine glands (steroid hormones) and from local synthesis (neurosteroids), changes in blood levels of steroids with age do not necessarily reflect changes in their brain levels. There is indeed strong evidence that neurosteroids are also synthesized in human brain and peripheral nerves. The development of a very sensitive and precise method for the analysis of steroids by gas chromatography/mass spectrometry (GC/MS) offers new possibilities for the study of neurosteroids. The concentrations of a range of neurosteroids have recently been measured in various brain regions of aged Alzheimer's disease patients and aged non-demented controls by GC/MS, providing reference values. In Alzheimer's patients, there was a general trend toward lower levels of neurosteroids in different brain regions, and neurosteroid levels were negatively correlated with two biochemical markers of Alzheimer's disease, the phosphorylated tau protein and the beta-amyloid peptides. The metabolism of dehydroepiandrosterone has also been analyzed for the first time in the aging brain from Alzheimer patients and non-demented controls. The conversion of dehydroepiandrosterone to Delta5-androstene-3beta,17beta-diol and to 7alpha-OH-dehydroepiandrosterone occurred in frontal cortex, hippocampus, amygdala, cerebellum and striatum of both Alzheimer's patients and controls. The formation of these metabolites within distinct brain regions negatively correlated with the density of beta-amyloid deposits.

Catabolic/anabolic balance and muscle wasting in patients with COPD

BACKGROUND

The mechanisms leading to muscle wasting in patients with COPD are still uncertain. This study was undertaken to evaluate the relationships among circulating levels of catabolic factors (ie, interleukin [IL]-6 and cortisol), anabolic factors (ie, bioavailable testosterone [Tbio], dehydroepiandrosterone sulfate [DHEAS], and insulin-like growth factor [IGF]-I), and mid-thigh muscle cross-sectional area (MTCSA) in patients with COPD.

METHODS

Serum levels of the above factors were measured in 45 men with COPD (mean [+/- SEM] FEV(1), 43 +/- 3% predicted; mean age, 67 +/- 1 years) and 16 sedentary healthy men of similar age. MTCSA was quantified using CT scanning. Patients with COPD were subdivided into two groups according to the MTCSA (< 70 or >or= 70 cm(2)).

RESULTS

There was a greater prevalence of hypogonadism (ie, Tbio, < 2 nmol/L) in patients with COPD compared to control subjects (22% vs 0%, respectively). Patients with an MTCSA of < 70 cm(2) had significantly reduced levels of DHEAS compared to those in healthy subjects (p < 0.01). IL-6 levels were significantly higher in both subgroups of COPD patients compared to those in control subjects (p < 0.005). The cortisol/DHEAS, IL-6/DHEAS, IL-6/Tbio, and IL-6/IGF-I ratios were significantly greater in COPD patients with an MTCSA of < 70 cm(2) compared to those in control subjects (p < 0.05). The cortisol/DHEAS and IL-6/DHEAS ratios were also significantly greater in COPD patients with an MTCSA of < 70 cm(2) than in COPD patients with an MTCSA of >or= 70 cm(2) (p < 0.05). In a stepwise multiple regression analysis, the IL-6/DHEAS ratio explained 20% of the variance in MTCSA (p < 0.005).

CONCLUSION

Catabolic/anabolic disturbances were found in COPD patients leading to a shift toward catabolism and possibly to the development of peripheral muscle wasting.

One- and two-year change in body composition as measured by DXA in a population-based cohort of older men and women

Changing body composition has been suggested as a pathway to explain age-related functional decline. No data are available on the expected changes in body composition as measured by dual-energy X-ray absorptiometry (DXA) in a population-based cohort of older persons. Body composition data at baseline, 1-yr follow-up, and 2-yr follow-up was measured by DXA in 2,040 well-functioning black and white men and women aged 70-79 yr, participants of the Health, Aging, and Body Composition Study. After 2 yr, a small decline in total body mass was observed (men: -0.3%, women: -0.4%). Among men, fat-free mass and appendicular lean soft tissue mass (ALST) decreased by -1.1 and -0.8%, respectively, which was masked by a simultaneous increase in total fat mass (+2.0%). Among women, a decline in fat-free mass was observed after 2 yr only (-0.6%) with no change in ALST and body fat mass. After 2 yr, the decline in ALST was greater in blacks than whites. Change in total body mass was associated with change in ALST (r = +0.58 to +0.70; P < 0.0001). Among participants who lost total body mass, men lost relatively more ALST than women, and blacks lost relatively more ALST than whites. In conclusion, the mean change in body composition after a 1- to 2-yr follow-up was 1-2% with a high interindividual variability. Loss of ALST was greater in men compared with women, and greater in blacks compared with whites, suggesting that men and blacks may be more prone to muscle loss.

The effect of growth hormone replacement therapy on adrenal androgen secretion in adult onset hypopituitarism

OBJECTIVE

Growth hormone replacement therapy in GH-deficient children is associated with enhanced adrenal androgen production, raising the possibility that GH might stimulate adrenocortical hormone secretion. This has not been extensively investigated in adults to date. GH is a potent modulator of the activity of the 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) enzyme and by altering cortisol metabolism can affect the function of the hypothalamo-pituitary-adrenal (HPA) axis and therefore potentially of adrenal androgen secretion. This study examined the effects of GH replacement in GH-deficient adults on adrenal androgen secretion.

DESIGN

Prospective study of the effect of GH replacement therapy on adrenal androgen production in patients with adult onset hypopituitarism over a 12-month period.

PATIENTS AND METHODS

Thirty adult GH-deficient patients were classified into two groups according to their cortisol responses to an insulin-induced hypoglycaemia or a glucagon stimulation test: 13 patients were adrenocorticotropic hormone (ACTH)-sufficient (nine females, age 45.1 +/- 3 years), whereas 17 patients were ACTH-deficient (11 females, age 45.5 +/- 3 years). Serum samples were collected before patients were initiated on GH replacement therapy using a dose titration regimen, and after 6 and 12 months on GH therapy for measurement of serum IGF-I, dehydroepiand-rosterone sulphate (DHEAS), Delta4-Androstenedione (A4), testosterone, cortisol, sex hormone binding globulin (SHBG) and cortisol binding globulin (CBG).

RESULTS

Six months after the initiation of GH replacement therapy, serum IGF-I levels were within the normal age-related reference range in both groups of patients and this was maintained at 12 months [in all patients 0 vs. 6 months: median (interquartile range): 92.5 ng/ml (73-116 ng/ml) vs. 191 ng/ml (159-224 ng/ml), P < 0.01]. In both ACTH-sufficient and -deficient groups of GH-deficient patients, pretreatment serum DHEAS levels were lower than the normal age-related reference range (P < 0.01); the ACTH-deficient patients had significantly lower DHEAS levels than the ACTH-sufficient patients [median (interquartile range): 0.5 micro mol/l (0.4-1.2 micro mol/l) vs. 1.5 micro mol/l (0.6-2.7 micro mol/l), P < 0.05]. Following GH replacement therapy, median levels of serum DHEAS levels rose from 1.5 micro mol/l (0.6-2.7 micro mol/l) to 1.9 micro mol/l (1.9-3.9 micro mol/l) in ACTH-sufficient patients, increasing in 11 of the 13 patients (P < 0.02). In this group, the median percentage increase from baseline was 32% at 6 months (P < 0.05). In contrast, baseline serum DHEAS levels [0.5 micro mol/l (0.4-1.2 micro mol/l)] declined in or from the measurable range in 47% of ACTH-deficient patients [median -16%; range -36-0] and only in one patient a + 0.2 micro mol/l increase was observed. GH dose requirements tended to be lower in ACTH-sufficient patients [1.2 U/day (0.8-1.4 U/day) vs. 1.6 U/day (1.0-2.0 U/day); P = 0.062]. There were no significant changes in serum testosterone, A4, SHBG and/or CBG levels, compared to the pretreatment levels, in either group of patients over the 12 months of GH replacement.

CONCLUSIONS

This study shows that median serum DHEAS levels are significantly lower in GH-deficient patients, even those with intact ACTH reserve, than in aged-matched controls. GH replacement therapy is associated with a significant increase in mean serum DHEAS only in ACTH-sufficient patients. These findings are consistent with either (i) GH stimulation of adrenal androgen production in the permissive presence of ACTH or (ii) an inhibitory effect of GH on 11beta-HSD type 1 activity leading to enhanced cortisol clearance, subsequent activation of the HPA axis and ACTH-mediated androgen secretion.

Anabolic and catabolic hormonal responses to experimental two-set low-volume resistance exercise in sedentary and active elderly people

BACKGROUND AND AIMS

The influence of acute low-volume resistance exercise on serum growth hormone (GH), insulin-like growth factor I (IGF-I), dehydroepiandrosterone sulphate (DHEAS), total testosterone (TT) and cortisol was ascertained in elderly subjects.

METHODS

Forty-seven independent, community-dwelling volunteers aged >65 years were recruited: 23 (11 men, 12 women) were sedentary individuals, and 24 (12 men, 12 women) had been regularly involved in physical activity for several years. The protocol consisted of two sets of leg extensions: one graded by loading to reach maximal power; the other consisted of 10 consecutive leg extensions using a load corresponding to maximal power.

RESULTS

IGF-I levels increased immediately after exercise, returning almost completely to pre-exercise values by the 15-minute post-exercise time point. The changes in all four study groups were similar. Not any of the groups presented systematic exercise-induced changes in circulating GH, DHEAS and TT levels. With respect to pre-exercise cortisol levels, significant decreases were observed both at the immediate and at the 15-minute post-exercise time points. These changes were independent of gender and physical activity level.

CONCLUSIONS

Our data indicate that low-volume resistance exercise may decrease cortisol levels and increase serum anabolic/catabolic hormone ratios. In view of the experimental character of our resistance training protocol and the lack of control-day data, these results should be corroborated by long-term low-volume resistance training programs.

The effect of dehydroepiandrosterone (DHEA) on recognition memory decision processes and discrimination in postmenopausal women

In this article, the theoretical distinction between recognition memory decision and discrimination processes is used to explore the effect of dehydroepiandrosterone (DHEA) in postmenopausal women. DHEA is an adrenal steroid that diminishes with aging. It has enhanced memory in laboratory animals. An 8-week placebo-controlled, double-blind experiment in which 30 women (ages 39-70) received a 50-mg/day oral dose of DHEA for 4 weeks demonstrated that DHEA made subjects more conservative (i.e., less likely to call test items "old") in their recognition memory decisions and enhanced recognition memory discrimination for items presented briefly. The former result may reflect an empirical regularity (Hirshman, 1995) in which recent strong memory experiences make participants more conservative. The latter result may reflect the effect of DHEA on visual perception, with consequent effects on memory. These results suggest the methodological importance of focusing on decision processes when examining the effects of hormones on memory.

Gender differences in resistance-training-induced myofiber hypertrophy among older adults

We tested the hypothesis that older men (n = 9, 69 +/- 2 years) would experience greater resistance-training-induced myofiber hypertrophy than older women (n = 5, 66 +/- 1 years) following knee extensor training 3 days per week at 65-80% of one-repetition maximum for 26 weeks. Vastus lateralis biopsies were analyzed for myofiber areas, myosin heavy chain isoform distribution, and levels of mRNA for insulin-like growth factor 1 (IGF-1), IGFR1, and myogenin. Gender x Training interactions (p <.05) indicate greater myofiber hypertrophy for all three primary fiber types (I, IIa, IIx) and enhanced one-repetition maximum strength gain in men compared with women (p <.05). Covarying for serum IGF-1, dehydroepiandrosterone sulfate, or each muscle mRNA did not negate these interactions. In both genders, type IIx myofiber area distribution and myosin heavy chain type IIx distribution decreased with a concomitant increase in type IIa myofiber area distribution (p <.05). In summary, gender differences in load-induced myofiber hypertrophy among older adults cannot be explained by levels of circulating IGF-1 or dehydroepiandrosterone sulfate, or by expression of the myogenic transcripts examined.

Role of hormones in the pathogenesis and management of sarcopenia

There is growing evidence to indicate that age-related declines in growth hormone (GH), insulin-like growth factor (IGF)-1, and androgen and estrogen production play a role in the pathogenesis of sarcopenia (an age-related decline in muscle mass and quality). Although GH supplementation has been reported to increase lean body mass in elderly individuals, the high incidence of adverse effects combined with a very high cost has limited the applicability of this form of therapy. The assessment of an alternative approach to enhance the GH/IGF-1 axis in the elderly by using GH-releasing hormone and other secretagogues is currently under way and is showing some promise. Testosterone replacement therapy may increase muscle mass and strength and decrease body fat in hypogonadal elderly men. Long-term randomised, controlled trials are needed, however, to better define the risk-benefit ratio of this form of therapy before it can be recommended. Available data are currently insufficient to decide what role estrogen replacement therapy may play in the management of sarcopenia. Therefore, although the evidence linking age-related hormonal changes to the development of sarcopenia is rapidly growing, it is still too early to determine the clinical utility of hormonal supplementation in the management of sarcopenia.

Pharmacology And Therapeutic Effects of Dehydroepiandrosterone In Older Subjects

Man and higher primates have adrenals that secrete large amounts of dehydroepiandrosterone (DHEA) [prasterone] and its sulphate (DHEAS) [PB 008]. A remarkable feature of plasma DHEAS levels in humans is their great decrease with aging. Researchers have postulated that this age-related decline of DHEAS levels may explain some of the degenerative changes associated with aging. Moreover, administration of DHEA to laboratory animals has demonstrable beneficial effects such as prevention of diabetes mellitus, obesity, cancer, heart disease and positive immunomodulator effects. However, in rodents DHEA(S) circulating levels are so low that it is impossible to detect any significant age-related decrease. Therefore results from rodent experiments are not relevant to human beings. Three mechanisms of action of DHEA(S) have been identified. DHEA and DHEAS are precursors of testosterone and estradiol, DHEAS is a neurosteroid which modulates neuronal excitability via specific interactions with neurotransmitter receptors and DHEA is an activator of calcium-gated potassium channels. Randomised, placebo-controlled clinical trials which included healthy individuals aged 60 years and over treated with (near) physiological doses of DHEA (50-100 mg/day) have yielded very few positive results. Impact of DHEA replacement treatment was assessed on mood, well being, cognitive and sexual functions, bone mass, body composition, vascular risk factors, immune functions and skin. The major limitations of these trials were their short duration (maximum 1 year) and the low number of study participants involved (maximum 280). Many elderly people in western countries take DHEA without medical supervision. In the US, DHEA is even classified as food supplement. At present there is no scientific evidence to recommend DHEA replacement in the elderly. Further studies are needed to form conclusions about the efficacy and the safety of DHEA replacement in elderly, and to better understand the mechanisms of action of DHEA at the molecular and cellular levels.

[DHEA: desire and resistance]

DHEA is a prohormone that is secreted by the corticoadrenal glands on a nyctohemeral rhythm alike to that of testosterone. Its plasmatic level gets reduced with ageing in a great amount of individuals, but not in all. Moreover, DHEA is a neurosteroid synthesized by certain neurons. As shown by correlation studies, lowered levels of DHEA wre linked to a higher death rate, in part of the studied population. Besides, an improvement in well being as well as in some mental functions, after a 50 mg daily intake, was shown in preliminary studies. Many well-conducted studies followed which only partially confirmed the previous ones. Nowadays, it seems to be taken for granted that DHEA becomes estrogens and androgens and that its action on women is mainly an androgenic one. DHEA becomes active after intracellular transformation, which varies according to the enzymatic set of cells. Some effect on elderly women's libido, and improvement in erectile dysfunction in men without vascular pathology but a lowered DHEA level, has been observed. Thus, using DHEA in order to cure sexual troubles might be considered, although the possible negative effects of DHEA, especially on breast and prostate, have not been discarded yet. The conditions under which it could have a beneficial effect on mental functions remains to be discovered. Acknowledgement of those pathological situations, in which DHEA could prove useful, as well as the administration posology is, therefore, crucial.

Transformations of DHEA and its metabolites by rat liver

Because dehydroepiandrosterone (DHEA) has a wide variety of weak beneficial effects in experimental animals and humans, we searched for metabolites of this steroid in the hope of finding more active compounds that might qualify for the title "steroid hormone." Incubation of DHEA with rat liver homogenate fortified with energy-yielding substrates resulted in rapid hydroxylation at the 7alpha-position of the molecule and subsequent conversion to other 7-oxygenated steroids in the sequence DHEA --> 7alpha-hydroxyDHEA --> 7-oxoDHEA --> 7beta-hydroxyDHEA, with branching to diols, triols, and sulfate esters. The ability of these metabolites to induce the formation of liver thermogenic enzyme activity increased from left to right in that sequence. A total of 25 different steroids were characterized, and at least six additional structures that are currently under study were produced from DHEA. 7-OxoDHEA is more effective than DHEA in enhancing memory performance in old mice and in reversing the amnesic effects of scopolamine.

Sarcopenia, weight loss, and nutritional frailty in the elderly

The progression of the aging process leads to a decreased margin of homeostatic reserve and a reduced ability to accommodate metabolic challenges, including nutritional stress. Nutritional frailty refers to the disability that occurs in old age owing to rapid, unintentional loss of body weight and loss of lean body mass (sarcopenia). Sarcopenia, a loss of muscle mass and strength, contributes to functional impairment. Weight loss is commonly due to a reduction in food intake; its possible etiology includes a host of physiological and nonphysiological causes. The release of cytokines during chronic disease may also be an important determinant of frailty. In addition to being anorectic, cytokines also contribute to lipolysis, muscle protein breakdown, and nitrogen loss. Whereas the multiple causes of nutritional frailty are not completely understood, clinical interventions for weight loss, sarcopenia, and cytokine alterations have been used with modest success.

Is there a relationship between fat-free soft tissue mass and low cognitive function? Results from a study of 7,105 women

OBJECTIVES

To test the hypothesis that low fat-free soft tissue mass and cognitive impairment are independently associated.

DESIGN

Cross-sectional study.

SETTING

Five geographic areas of France.

PARTICIPANTS

Seven thousand one hundred five community-dwelling women aged 75 and older recruited from electoral rolls between 1992 and 1994.

MEASUREMENTS

Fat-free soft tissue mass, body fat mass, and bone mineral density were measured using dual-energy x-ray absorptiometry. Study participants were assessed for cognitive impairment using the Short Portable Mental Status Questionnaire and divided into two groups according to their scores. Logistic regression models were used to calculate multivariate-adjusted differences in body composition between two groups of subjects according to their cognitive function.

RESULTS

After adjustment for confounders, compared with women in the highest quartile of fat-free soft tissue mass, women in the lowest quartile had an odds ratio of 1.43 (95% confidence interval (CI) = 1.07-1.91) for cognitive impairment. Low fat mass was also associated with lower cognitive function, with an odds ratio of 1.35 (95% CI = 1.01-1.79) for the lower quartile of fat mass compared with the highest quartile. There was no association between cognitive impairment and bone mineral density.

CONCLUSIONS

This finding supports the hypothesis that low muscle mass is associated with cognitive impairment in older women. These two components represent major causes of frailty and functional decline in older people and could have some common mechanisms. Nevertheless, these results do not predict the causal variable.

[Relation between physical activity, muscle function and IGF-1, testosterone and DHEAS concentrations in the elderly]

OBJECTIVE

Lower amounts of circulating anabolic hormones are thought to accelerate the age related decline in muscle mass and function. Replacement therapies are promising interventions but there are problems with these therapies. Thus alternative strategies should be developed. The age related changes in hormonal status may be probably influenced by exercise. The purpose of this study was: a) to confirm with other methods, more adapted for elderly people, the results of a previous study that has shown relationship between physical activity (PA) and quadriceps muscle function with dehydroepiandrosterone sulphate (DHEAS), insulin like growth factor-1 (IGF-1). Quadriceps muscle power (Pmax) is measured in this new work with a recently developed leg extensor machine and, b) to complete the results of the first study examining simultaneously the relationship between PA, Pmax and cardiorespiratory fitness (VO2max) with DHEAS, IGF-1 and testosterone in a group of healthy elderly people.

METHODS

Fifty independent, community dwelling elderly subjects (25 mens and 25 womens) aged from 66 to 84 volunteered to participate in the study. PA was evaluated by the questionnaire and expressed using two activity indices: mean habitual daily energy expenditure (MHDEE) and the daily energy expenditure corresponding to leisure time sports activities (Sports Activity). Pmax and optimal shortening velocity (vopt) were measured on a Ergopower dynamometer. The Pmax was expressed relative to body mass, Pmax/kg (W kg-1), and relative to the mass of the two quadriceps muscles, Pmax/Quadr (W.kgQuadr-1). VO2max has been measured during a maximal treadmill exercise.

RESULTS

In women, IGF-1 correlated significantly with MHDEE (r = 0.54, P = 0.004), Pmax/kg (r = 0.54, P = 0.004) and Pmax/Quadr (r = 0.46, P = 0.02), whereas DHEAS with MHDEE (r = 0.54, P = 0.004), Sports Activity (r = 0.65, P < 0.001), VO2max (r = 0.46, P = 0.02), Pmax/kg (r = 0.46, P = 0.02) and Pmax/Quadr (r = 0.55, P = 0.004). No such correlation was found in men.

CONCLUSION

These findings confirm that in healthy elderly women physical activity, cardiorespiratory fitness and quadriceps muscle function are similarly related to levels of circulating DHEAS and IGF-1 suggesting a favourable influence of exercise on anabolic hormonal production in the elderly.

DHEA treatment: myth or reality?

Dehydroepiandrosterone (DHEA) and its sulfate ester are major secretory products of the human adrenal. Serum DHEA concentrations decline with advancing age and DHEA supplementation in elderly people has been advertized as anti-aging medication. However, such claims are based on experiments in rodents with a fundamentally different DHEA physiology. In humans, DHEA is a crucial precursor of sex steroid biosynthesis and exerts indirect endocrine and intracrine actions following conversion to androgens and estrogens. In addition, it acts as a neurosteroid via effects on neurotransmitter receptors in the brain. DHEA has considerable effects on mood, well-being and sexuality in patients with adrenal insufficiency, and also in those with mood disorders. However, subjects with a physiological, age-related decline in DHEA secretion show little benefit from DHEA administration. Future research should focus on DHEA treatment for adrenal insufficiency, and DHEA administration in both patients receiving chronic glucocorticoid treatment and women with androgen deficiency.

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.