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1.
Curr Opin Clin Nutr Metab Care ; 16(1): 3-13, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23222704

RESUMO

PURPOSE OF REVIEW: Sarcopenia is a geriatric syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength with a risk of adverse outcomes such as physical disability, poor quality of life, and death. Sarcopenia is a multifactorial process involving the decline of androgens, including dehydroepiandrosterone sulphate (DHEAS) and testosterone. The aim of this review is to highlight the effects of DHEAS and testosterone treatment to counteract sarcopenia, especially in older men. RECENT FINDINGS: DHEAS and, more importantly, testosterone treatment are associated with increased muscle mass, whereas the effects on muscle function and physical performance are less clear. The results of recent randomized placebo controlled trials with DHEAS in older men and women and testosterone in men with mobility limitation are discussed. The novel current and future scenarios to attenuate the detrimental effects and to optimize the efficacy of sex hormone treatment are also addressed. SUMMARY: DHEAS and testosterone are important options in the armamentarium of sarcopenia treatment in older men. Future studies are needed to address new approaches by using selective compounds, targeting the correct form and dosage, tailoring the correct patient to treat, and taking into account the multifactorial origin and the new definition of sarcopenia.


Assuntos
Sulfato de Desidroepiandrosterona/administração & dosagem , Suplementos Nutricionais , Sarcopenia/fisiopatologia , Testosterona/administração & dosagem , Idoso , Androgênios/administração & dosagem , Androgênios/sangue , Sulfato de Desidroepiandrosterona/sangue , Relação Dose-Resposta a Droga , Feminino , Avaliação Geriátrica , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Masculino , Atividade Motora , Músculo Esquelético/fisiopatologia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Testosterona/sangue
2.
Curr Opin Endocrinol Diabetes Obes ; 18(3): 171-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21478748

RESUMO

PURPOSE OF REVIEW: Levels of dehydroepiandrosterone (DHEA) are known to decline with age. In an era of increasing use of supplements to better life, the benefits of DHEA in the aging female population are controversial. The goal of this article is to critically review published studies to determine if there is a role for DHEA supplementation in postmenopausal women. RECENT FINDINGS: Daily administration of oral DHEA achieves serum concentrations similar to those of women in their 20s. Several observational studies have shown that lower DHEA levels are associated with increased cardiovascular risk in women; however, interventional trials show no improvement in atherosclerosis or cardiovascular risk factors, and a lowering of HDL cholesterol levels. DHEA supplementation modestly increases bone mineral density in conjunction with adjuvant therapies and improves cognition in those with mild-to-moderate cognitive impairment, but does not affect cognition in unimpaired women. Use of intravaginal DHEA, but not oral DHEA, alleviates vaginal atrophy and improves sexual function in postmenopausal women. SUMMARY: On the basis of current evidence, there is no role for oral DHEA supplementation in healthy, postmenopausal women. Where benefits have been shown, long-term studies are needed to confirm these benefits and verify the safety profile of DHEA.


Assuntos
Sulfato de Desidroepiandrosterona/metabolismo , Pós-Menopausa/metabolismo , Atrofia/prevenção & controle , Densidade Óssea , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Transtornos Cognitivos/prevenção & controle , Sulfato de Desidroepiandrosterona/administração & dosagem , Suplementos Nutricionais , Feminino , Humanos , Risco , Vagina/patologia
3.
Int Immunopharmacol ; 9(11): 1342-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19646552

RESUMO

The present study tested the hypothesis that the oral administration of DHEAS enhances the in vitro and the in vivo immune response of young pigs. Crossbred, female pigs (80 days of age; 49+/-2 kg) were separated into two treatment groups (n=4/treatment) receiving either 0mg/kg (control) or 1mg/kg DHEAS twice daily (DHEAS) for 5 weeks. On day 7 pigs were immunized against KLH and ovalbumin. Body weight increased weekly throughout the study but did not differ between treatment groups. While white blood cell counts increased in response to immunization but did not differ between treatments, the neutrophil:lymphocyte ratio was enhanced (P<0.05) in DHEAS-supplemented pigs. Concanavalin A (ConA) induced an in vitro dose-dependent increase (P<0.05) in lymphocyte proliferation, but treatment did not affect proliferation prior to immunization. However, lymphocytes isolated from DHEAS-supplemented pigs displayed a greater increase in proliferation following immunization relative to control pigs (P<0.05). Dexamethasone (DEX) attenuated ConA-induced lymphocyte proliferation, with DHEAS-supplemented pigs retaining a greater proliferative response relative to control pigs (P<0.05). Serum IgG concentrations and relative concentrations of antigen-specific IgG increased after immunization with maximum values attained at 21 and 28 days for control and DHEAS-supplemented pigs, respectively. The DHEAS-supplemented pigs had greater (P<0.05) concentrations of IgG and relative concentrations of antigen-specific IgG compared to control pigs. Collectively these data suggest DHEAS supplementation increases the responsiveness of young pigs to antigenic challenge, and may be beneficial for improving their immune function.


Assuntos
Sulfato de Desidroepiandrosterona/farmacologia , Hemocianinas/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ovalbumina/imunologia , Adjuvantes Imunológicos , Administração Oral , Animais , Peso Corporal , Sulfato de Desidroepiandrosterona/administração & dosagem , Sulfato de Desidroepiandrosterona/sangue , Dexametasona/farmacologia , Feminino , Imunoglobulina G/sangue , Distribuição Aleatória , Suínos , Vacinação
4.
Cell Mol Neurobiol ; 26(7-8): 1505-19, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16758322

RESUMO

1. Dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) are sex hormone precursors which exert marked neurotrophic and/or neuroprotective activity in the central nervous system (CNS). 2. In the present electrophysiological experiments, we studied the effects of peripherally administered DHEAS on responses of the primary somatosensory (SSI) and motor cortices (MI) of (i) anesthetized controls and (ii) MI focal cold-lesioned rats. (iii) The effects of DHEAS on the field excitatory postsynaptic potentials (fEPSPs) were also studied in vitro brain slices. DHEAS (50 mg/kg) was injected subcutaneously 12 h before and immediately after cold lesion induction. The anesthetized rats were fixed in a stereotaxic frame, the SSI and MI were exposed, and control SSI and MI responses were evoked by contralateral whisker pad stimulation. After registration of the evoked responses for a 35-min period, a copper cylinder (2 mm in diameter) cooled with a mixture of acetone and dry ice (-78 degrees C) was applied to produce a lesion in the MI and the registration of the evoked responses was then continued for an additional 360 min. 3. In the controls, DHEAS administration resulted in slight increases in amplitude of both the SSI and the MI responses. After focal cold lesion induction, the most significant reduction in amplitude was observed at the focus of the lesion in the primary MI, but the amplitudes of the SSI responses were also decreased. After 3-5 h of lesion induction, the amplitudes started to increase around the injury in the primary MI, while the SSI response had already started to recover 2 h after induction of the MI lesion. In the course of the postlesion recovery period, the MI responses peripherally to the center of the lesion frequently exhibited extremely high and low amplitudes. The paired-pulse paradigm revealed changing, but basically high levels of disinhibition and facilitation in extended cortical areas after focal cortical cold lesion induction. The deviations (e.g., the extremely augmented responses) in cortical functioning of the anesthetized rats were unambiguously diminished by DHEAS administration, and the period required for the cortical responses to recover was significantly shorter after the steroid treatment. In the in vitro studies, however, DHEAS administration resulted in an enhanced level of disinhibition in extended cortical areas of both the hemispheres. 4. This observation draws attention to the possible differences between the results obtained in different models (in vitro vs. in situ). Nevertheless, all the presented data suggest that DHEAS treatment might have neuroprotective effect on the neocortex at least at a short-time scale.


Assuntos
Lesões Encefálicas/fisiopatologia , Sulfato de Desidroepiandrosterona/farmacologia , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Córtex Motor/efeitos dos fármacos , Animais , Lesões Encefálicas/tratamento farmacológico , Sulfato de Desidroepiandrosterona/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Injeções Subcutâneas , Masculino , Modelos Biológicos , Córtex Motor/fisiologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Wistar , Córtex Somatossensorial/efeitos dos fármacos
5.
Int J Neurosci ; 116(2): 141-55, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16393880

RESUMO

Previous work has suggested that DHEA supplementation may have adverse cognitive effects in elderly women. This article analyzed 24-h measurements of DHEA, DHEAS, and cortisol to determine if cognitive decrease with treatment is mediated by DHEA's impact on endogenous cortisol. It was found that DHEA administration increased cortisol at several hours during the day. In the treatment group, cortisol was positively associated with cognition at study completion. An increase in negative associations between DHEA(S) levels and cognition was found at completion. Increased cortisol does not explain the cognitive deficits associated with DHEA, suggesting a direct negative effect of exogenous DHEA on cognition.


Assuntos
Cognição/efeitos dos fármacos , Sulfato de Desidroepiandrosterona/sangue , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/sangue , Hidrocortisona/sangue , Pós-Menopausa/sangue , Pós-Menopausa/efeitos dos fármacos , Administração Oral , Idoso , Cognição/fisiologia , Sulfato de Desidroepiandrosterona/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Nootrópicos/administração & dosagem , Nootrópicos/sangue
6.
J Endocrinol Invest ; 28(3 Suppl): 85-93, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16042365

RESUMO

DHEA and its sulfate prohormone DHEAS are the most abundant circulating adrenal steroid hormones in humans. DHEA exerts its actions on peripheral target tissues either indirectly, following its conversion to androgens, estrogens or both, or directly, as a steroid hormone interacting with either a nuclear or a membrane receptor. In humans, DHEA shows a characteristic pattern of secretion throughout life. Serum DHEA concentrations decline with advancing age and vary with gender, ethnicity, and environmental factors. Epidemiological studies show an inverse relationship between plasma DHEA(S) levels in men and age-related illnesses, including cardiovascular and metabolic diseases, immune disorders, malignancies, and neurological dysfunction. This has generated great interest on the putative role of DHEA in age-associated illnesses. Administration of DHEA to rats and mice reduces visceral fat accumulation, and improves insulin resistance in experimental models of diet-induced obesity and/or Type 2 diabetes. In addition, recent studies in vitro have shown that DHEA has the capacity to improve endothelial function by increasing nitric oxide (NO) synthesis. Replacement of DHEA in patients with adrenal insufficiency has been shown to exert beneficial effects on well-being, mood, and sexuality. By contrast, in healthy individuals, the physiological age-associated decline in circulating DHEA(S) per se does not justify DHEA supplementation, since the effects of this hormone on metabolic abnormalities, endothelial function in vivo, and cardiovascular events are contradictory. However, these results do not exclude the possibility that DHEA treatment may prove beneficial in specific subgroups of elderly subjects.


Assuntos
Envelhecimento , Sulfato de Desidroepiandrosterona/sangue , Insuficiência Adrenal , Afeto , Animais , Composição Corporal/efeitos dos fármacos , Densidade Óssea , Sulfato de Desidroepiandrosterona/administração & dosagem , Sulfato de Desidroepiandrosterona/metabolismo , Diabetes Mellitus Tipo 2 , Endotélio Vascular/efeitos dos fármacos , Terapia de Reposição Hormonal , Humanos , Resistência à Insulina , Masculino , Neoplasias , Obesidade
7.
Forensic Sci Int ; 143(2-3): 103-14, 2004 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-15240029

RESUMO

A simple means of detecting the abuse of steroids that also occur naturally is a problem facing doping control laboratories. Specific markers are required to allow the detection of the administration of these steroids. These markers are commonly measured using a set of data obtained from the screening of samples by gas chromatography-mass spectrometry (GC-MS). Doping control laboratories further need to confirm identified abuse using techniques such as gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). An interesting urinary species was found while following the pharmacokinetics and changes to the steroid profile from single and multiple oral doses of the International Olympic Committee/World Anti Doping Agency (IOC/WADA) prohibited substance, dehydroepiandrosterone (DHEA). The urine samples collected from the administration studies were subject to GC-MS and GC-C-IRMS steroid analysis following cleanup by solid phase extraction techniques. A useful urinary product of DHEA administration was detected in the urine samples from each of the administration studies and was identified by GC-MS experiments to be 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo). This compound occurs naturally but the concentrations of 3alpha,5-cyclo were elevated following both the single DHEA administration (up to 385 ng/mL) and multiple DHEA administrations (up to 1240 ng/mL), in relation to those observed prior to these administrations (70 and 80 ng/mL, respectively). A reference distribution of urine samples collected from elite athletes (n = 632) enabled the natural concentration range of 3alpha,5-cyclo to be established (0-280 ng/mL), with a mean concentration of 22 ng/mL. Based on this an upper 3alpha,5-cyclo concentration limit of 140 ng/mL is proposed as a GC-MS screening marker of DHEA abuse in athletes. GC-C-IRMS analysis revealed significant 13C depletion of 3alpha,5-cyclo following DHEA administration. In the single administration study, the delta13C value of 3alpha,5-cyclo changed from -24.3 per thousand to a minimum value of -31.1 per thousand at 9 h post-administration, before returning to its original value after 48 h. The multiple administration study had a minimum delta13C 3alpha,5-cyclo of -33.9 per thousand during the administration phase in contrast to the initial value of -24.2 per thousand. Preliminary studies have shown 3alpha,5-cyclo to most likely be produced from DHEA sulfate found at high levels in urine. The complementary use of GC-MS and GC-C-IRMS to identify new markers of steroid abuse and the application of screening criteria incorporating such markers could also be adapted by doping control laboratories to detect metabolites of androstenedione, testosterone and dihydrotestosterone abuse.


Assuntos
Androstanos/urina , Sulfato de Desidroepiandrosterona/farmacocinética , Sulfato de Desidroepiandrosterona/urina , Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Adulto , Androstanos/química , Androstanóis/urina , Biomarcadores/urina , Sulfato de Desidroepiandrosterona/administração & dosagem , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Marcação por Isótopo , Isótopos , Masculino , Espectrometria de Massas/métodos , Estrutura Molecular , Valores de Referência
8.
Biomed Sci Instrum ; 35: 279-84, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11143362

RESUMO

Recent studies have documented that conventional administration (orally or injections) of DHEA (Dehydroepiandrosterone) or DHEAS (Dehydroepiandrosterone Sulfate) have induced alteration in tissues of the reproductive track of male rats. However, the exact mechanism of this physiological response has not been extensively studied. In addition, the route of DHEA or DHEAS administration has not been fully investigated. The specific objectives of this study were: (1) to deliver DHEA and DHEAS at a sustained level by means of TCPL delivery system, and (2) to evaluate the ultrastructural changes associated with sustained delivery of DHEA and DHEAS at the reproductive and vital organs level. A total of 12 adult male rats (BW 250-270 gm) were randomly divided into four equal groups. Groups 1-3 were implanted with TCPL ceramic capsules loaded with 200 mg DHEA (low dose), 600 mg DHEA (high dose) and 200 mg DHEAS, respectively. Aseptic surgical techniques were performed throughout the experiment. Blood (2 mls) was collected every other day for biochemical analysis. The weights were recorded bi-weekly. At the end of 21 days post-implantation, all control and experimental animals were sacrificed following standard lab procedure (overdose of Halothane). The reproductive and vital organs were collected, weighed, fixed, embedded, sectioned, and stained (H&E) for histological evaluations. Data obtained from this investigation suggest the following: (1) body weights between the experimental (DHEA and DHEAS) and control were unchanged, (2) weights of the reproductive were significantly different than controls, (3) kidney weights wee the only vital organ that was statistically different than controls, (4) prostatic tissue of the experimental group showed signs of atrophy, and (5) focal atrophy was also evident in the seminferous tubules and testes of DHEA and DHEAS treated rats. Overall conclusion of this study suggest that in male rats, the use of DHEA and DHEAS in a sustained delivery system seems to show some physiological changes in the vital and reproductive organs.


Assuntos
Fosfatos de Cálcio , Sulfato de Desidroepiandrosterona/farmacologia , Desidroepiandrosterona/farmacologia , Genitália Masculina/efeitos dos fármacos , Animais , Cerâmica , Desidroepiandrosterona/administração & dosagem , Sulfato de Desidroepiandrosterona/administração & dosagem , Sistemas de Liberação de Medicamentos , Implantes de Medicamento , Genitália Masculina/anatomia & histologia , Rim/anatomia & histologia , Rim/efeitos dos fármacos , Lisina , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fosfatos , Ratos , Ratos Sprague-Dawley
9.
Biochim Biophys Acta ; 1344(3): 201-9, 1997 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-9059510

RESUMO

Alteration in energy metabolism of postmenopausal women might be related to the reduction of dehydroepiandrosterone sulfate (DHEAS). DHEA and DHEAS decline with age, leveling at their nadir near menopause. DHEA and DHEAS modulate fatty acid metabolism by regulating carnitine acyltransferases and CoA. The purpose of this study was to determine whether dietary supplementation with DHEAS would also increase tissue L-carnitine levels, carnitine acetyltransferase (CAT) activity and mitochondrial respiration in oophorectomized rats. Plasma L-carnitine levels rose following oophorectomy in all groups (P < 0.0001). Supplementation with DHEAS was not associated with further elevation of plasma L-carnitine levels, but with increased hepatic total and free L-carnitine (P = 0.021 and P < 0.0001, respectively) and cardiac total L-carnitine concentrations (P = 0.045). In addition, DHEAS supplementation increased both hepatic and cardiac CAT activities (P < 0.0001 and P = 0.05 respectively). CAT activity positively correlated with the total and free carnitine levels in both liver and heart (r = 0.764, r = 0.785 and r = 0.700, r = 0.519, respectively). Liver mitochondrial respiratory control ratio, ADP:O ratio and oxygen uptake were similar in both control and supplemented groups. These results demonstrate that in oophorectomized rats, dietary DHEAS supplementation increases the liver and heart L-carnitine levels and CAT activities. In conclusion, DHEAS may modulate L-carnitine level and CAT activity in estrogen deficient rats. The potential role of DHEAS in the regulation of fatty acid oxidation in postmenopausal women is worthy of investigation.


Assuntos
Carnitina O-Acetiltransferase/metabolismo , Carnitina/metabolismo , Sulfato de Desidroepiandrosterona/farmacologia , Mitocôndrias Hepáticas/metabolismo , Animais , Carnitina O-Acetiltransferase/sangue , Sulfato de Desidroepiandrosterona/administração & dosagem , Dieta , Feminino , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Miocárdio/enzimologia , Miocárdio/metabolismo , Ovariectomia , Consumo de Oxigênio , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Rotenona/metabolismo , Succinatos/metabolismo , Ácido Succínico
10.
Vaccine ; 14(16): 1531-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9014295

RESUMO

Elderly individuals often exhibit a poorer immune response and shorter duration of immunity to vaccines than younger persons. Improvement in vaccine response has been demonstrated when administering the hormone dehydroepiandrosterone sulfate (DHEAS) as an adjuvant in animal trials. Two separate, randomized double-blinded vaccine trials were therefore conducted using DHEAS as an oral adjuvant in individuals age 65 or older. Sixty-six individuals were randomized to DHEAS, 50 mg po bid for 4 days, or a placebo capsule. Tetanus vaccination was given immediately before the fifth dose. At entry the level of protective antibody was age-dependent (P = 0.009), and by 28 days post-vaccination most individuals had protective levels of antibody, with no difference noted between treatment groups. In the second study, 67 individuals received placebo capsules or DHEAS immediately before and 24 h after influenza vaccination. The number of individuals who developed protective titers (> or = 1:40) was not different in the two groups. The mean log increase in HAI response was greater in the DHEAS group to all three vaccine components, although this did not achieve significance. Minimal side-effects of DHEAS administration were noted. Given the trend toward improved response in the elderly to influenza, larger trials using DHEA as an adjuvant in vaccines that are neoantigens may be indicated.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Sulfato de Desidroepiandrosterona/imunologia , Vacinas contra Influenza/imunologia , Toxoide Tetânico/imunologia , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Sulfato de Desidroepiandrosterona/administração & dosagem , Sulfato de Desidroepiandrosterona/sangue , Método Duplo-Cego , Feminino , Humanos , Vacinas contra Influenza/efeitos adversos , Masculino , Toxoide Tetânico/efeitos adversos
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