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1.
Drug Test Anal ; 15(8): 853-864, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37055939

RESUMEN

The frequent detection of anabolic androgenic steroids (AAS) indicates their popularity among rule-breaking athletes. The so called long-term metabolites play a crucial role in their detection, and non-hydrolysed sulphated metabolites have gained renewed interest, as research has demonstrated their extended detection time compared to the more conventional markers (e.g., for metenolone and mesterolone). Their potential has been investigated using liquid and gas chromatography-mass spectrometry (LC- and GC-MS). However, due to their complementary nature, chances are that the most promising metabolite on one technique does not necessarily exhibit the same behaviour on the other and vice versa. Therefore, a comparison was carried out where as a trial model, metenolone, mesterolone and 17α-methyltestosterone were selected and the most likely long-term sulphated metabolites identified on four mass spectrometric instruments. Additionally, using a modified sample preparation procedure, comparison between conventional and non-hydrolysed sulphated metabolites between different GC-MS instruments was also included. When focusing on each individual marker, no cases were observed where a single metabolite provided a superior detection time on all instruments. Furthermore, for each AAS, there were incidences where a metabolite provided the best detection time on one instrument but could only be detected for a shorter period or not at all on other instruments. This demonstrates that metabolite detection windows and hence their added-value as target substance are unique and dependent on the analytical technique and not only on their pharmacokinetic behaviour. Consequently, in each case, a metabolite versus instrument evaluation is needed to maximise the probabilities of detecting doping offences.


Asunto(s)
Anabolizantes , Doping en los Deportes , Humanos , Anabolizantes/metabolismo , Esteroides Anabólicos Androgénicos , Cromatografía de Gases y Espectrometría de Masas/métodos , Mesterolona/metabolismo , Metenolona , Metiltestosterona/química , Metiltestosterona/metabolismo , Detección de Abuso de Sustancias/métodos , Sulfatos , Espectrometría de Masas en Tándem/métodos
2.
Neurochem Res ; 47(7): 2032-2042, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35415802

RESUMEN

Decreased anabolic androgen levels are followed by impaired brain energy support and sensing with loss of neural connectivity during physiological aging, providing a neurobiological basis for hormone supplementation. Here, we investigated whether nandrolone decanoate (ND) administration mediates hypothalamic AMPK activation and glucose metabolism, thus affecting metabolic connectivity in brain areas of adult and aged mice. Metabolic interconnected brain areas of rodents can be detected by positron emission tomography using 18FDG-mPET. Albino CF1 mice at 3 and 18 months of age were separated into 4 groups that received daily subcutaneous injections of either ND (15 mg/kg) or vehicle for 15 days. At the in vivo baseline and on the 14th day, brain 18FDG-microPET scans were performed. Hypothalamic pAMPKT172/AMPK protein levels were assessed, and basal mitochondrial respiratory states were evaluated in synaptosomes. A metabolic connectivity network between brain areas was estimated based on 18FDG uptake. We found that ND increased the pAMPKT172/AMPK ratio in both adult and aged mice but increased 18FDG uptake and mitochondrial basal respiration only in adult mice. Furthermore, ND triggered rearrangement in the metabolic connectivity of adult mice and aged mice compared to age-matched controls. Altogether, our findings suggest that ND promotes hypothalamic AMPK activation, and distinct glucose metabolism and metabolic connectivity rearrangements in the brains of adult and aged mice.


Asunto(s)
Anabolizantes , Nandrolona , Proteínas Quinasas Activadas por AMP/metabolismo , Anabolizantes/metabolismo , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Suplementos Dietéticos , Fluorodesoxiglucosa F18 , Glucosa/metabolismo , Ratones , Nandrolona/metabolismo , Nandrolona/farmacología , Nandrolona Decanoato , Tomografía de Emisión de Positrones
3.
Environ Sci Pollut Res Int ; 27(5): 5009-5017, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31845274

RESUMEN

Nandrolone decanoate (ND) is a commonly used anabolic-androgenic steroid. These drugs are illegally self-administered by athletes to enhance their sports performance. However, their abuse could influence the testicular function and fertility. The main objective of this study was to evaluate the possible protective effects of Cynara scolymus leaf extract (CLE) on ND-induced testicular dysfunction in rats. Five groups of adult male rats (10 rats each) were used. Group I rats received only saline and served as controls. Group II rats were injected with a vehicle once weekly, while group III rats received intramuscular injections of ND (20 mg/kg/week for 60 days). Group IV rats orally received 1 g/kg/day of CLE and group V rats received ND and CLE at the aforementioned doses. The results revealed that ND has a negative impact on the testicular function as evidenced by the significant increases (p ≤ 0.05) in testicular malondialdehyde concentration and serum non-prostatic acid phosphatase activity, as well as the significant decreases in serum testosterone levels, testicular weight, glutathione concentration, catalase enzyme activity, and total antioxidant capacity. These results were accompanied by considerable alterations of sperm characters and histopathological studies of the testicular tissue. However, co-treatment with CLE extract significantly alleviated (p ≤ 0.05) almost all ND-induced pathological alterations. In conclusion, co-treatment of ND-intoxicated rats with CLE ameliorated the toxic effects of ND on the testicular structure and function, probably due to its antioxidant activity.


Asunto(s)
Anabolizantes , Cynara scolymus , Nandrolona , Testículo/fisiología , Anabolizantes/aislamiento & purificación , Anabolizantes/metabolismo , Animales , Cynara scolymus/química , Masculino , Nandrolona Decanoato , Extractos Vegetales , Ratas , Ratas Wistar , Espermatozoides
4.
Br J Nutr ; 117(7): 911-922, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28446262

RESUMEN

Branched-chain amino acids (BCAA) have been clearly demonstrated to have anabolic effects on muscle protein synthesis. However, little is known about their roles in the regulation of net AA fluxes across skeletal muscle in vivo. This study was aimed to investigate the effect and related mechanisms of dietary supplementation of BCAA on muscle net amino acid (AA) fluxes using the hindlimb flux model. In all fourteen 4-week-old barrows were fed reduced-protein diets with or without supplemental BCAA for 28 d. Pigs were implanted with carotid arterial, femoral arterial and venous catheters, and fed once hourly with intraarterial infusion of p-amino hippurate. Arterial and venous plasma and muscle samples were obtained for the measurement of AA, branched-chain α-keto acids (BCKA) and 3-methylhistidine (3-MH). Metabolomes of venous plasma were determined by HPLC-quadrupole time-of-flight-MS. BCAA-supplemented group showed elevated muscle net fluxes of total essential AA, non-essential AA and AA. As for individual AA, muscle net fluxes of each BCAA and their metabolites (alanine, glutamate and glutamine), along with those of histidine, methionine and several functional non-essential AA (glycine, proline and serine), were increased by BCAA supplementation. The elevated muscle net AA fluxes were associated with the increase in arterial and intramuscular concentrations of BCAA and venous metabolites including BCKA and free fatty acids, and were also related to the decrease in the intramuscular concentration of 3-MH. Correlation analysis indicated that muscle net AA fluxes are highly and positively correlated with arterial BCAA concentrations and muscle net BCKA production. In conclusion, supplementing BCAA to reduced-protein diet increases the arterial concentrations and intramuscular catabolism of BCAA, both of which would contribute to an increase of muscle net AA fluxes in young pigs.


Asunto(s)
Aminoácidos de Cadena Ramificada/administración & dosificación , Anabolizantes/administración & dosificación , Dieta con Restricción de Proteínas/veterinaria , Desarrollo de Músculos , Proteínas Musculares/biosíntesis , Músculo Esquelético/metabolismo , Regulación hacia Arriba , Aminoácidos/sangre , Aminoácidos/metabolismo , Aminoácidos de Cadena Ramificada/sangre , Aminoácidos de Cadena Ramificada/metabolismo , Anabolizantes/sangre , Anabolizantes/metabolismo , Animales , China , Cruzamientos Genéticos , Dieta con Restricción de Proteínas/efectos adversos , Ácidos Grasos no Esterificados/sangre , Ácidos Grasos no Esterificados/metabolismo , Miembro Posterior , Técnicas de Dilución del Indicador , Cetoácidos/sangre , Cetoácidos/metabolismo , Masculino , Metabolómica/métodos , Metilhistidinas/sangre , Metilhistidinas/metabolismo , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/crecimiento & desarrollo , Orquiectomía/veterinaria , Flujo Sanguíneo Regional , Sus scrofa , Aumento de Peso
5.
Drug Test Anal ; 8(5-6): 525-34, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27443207

RESUMEN

To ensure fair competition and to protect the horse's welfare, horses have to compete on their own merits, without any unfair advantage that might follow the use of drugs. Therefore, regulatory authorities list all substances that are not allowed in competition, including most anabolic-androgenic steroids. As zero-tolerance is retained, the question arose whether the consumption of mouldy feed could lead to the excretion of steroids, due to the biotransformation of plant phytosterols to steroids. A rapid ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analytical method, previously validated according to AORC (Association of Official Racing Chemists) and EC (European Commission) guidelines, was used to measure steroids in different sample types. Multiple mouldy feed samples were tested for the presence of steroids. The effect of digestion was tested by in vitro simulation of the horse's hindgut in batch incubations. In most feed samples no steroids were detected, even when the products were mouldy. Mouldy corn however showed to contain up to 3.0 ± 0.4 µg/kg AED (4-androstenedione), the main testosterone precursor. This concentration increased when mouldy corn (with added phytosterols) was digested in vitro. An herbal phytosupplement also showed to contain α-testosterone. These results demonstrate that it is important to caution against the consumption of any feed or (herbal) supplement of which the detailed ingredients and quantitative analysis are unknown. The consumption of mouldy corn should especially be avoided, not only from a horse health and welfare point of view, but also to avoid possible inadvertent positive doping results. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Anabolizantes/análisis , Andrógenos/análisis , Alimentación Animal/análisis , Alimentación Animal/microbiología , Heces/química , Caballos/orina , Esteroides/análisis , Aerobiosis , Anabolizantes/metabolismo , Anabolizantes/orina , Andrógenos/metabolismo , Andrógenos/orina , Animales , Biotransformación , Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Suplementos Dietéticos/microbiología , Doping en los Deportes , Caballos/metabolismo , Mucor/metabolismo , Mycobacterium/metabolismo , Fitosteroles/análisis , Fitosteroles/metabolismo , Fitosteroles/orina , Esteroides/metabolismo , Esteroides/orina , Espectrometría de Masas en Tándem/métodos , Testosterona/análisis , Testosterona/metabolismo , Testosterona/orina , Zea mays/química , Zea mays/microbiología
6.
J Steroid Biochem Mol Biol ; 152: 180-92, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26094581

RESUMEN

Traditionally, steroids other than testosterone are considered to be synthetic, anabolic steroids. Nevertheless, in stallions, it has been shown that ß-Bol can originate from naturally present testosterone. Other precursors, including phytosterols from feed, have been put forward to explain the prevalence of low levels of steroids (including ß-Bol and ADD) in urine of mares and geldings. However, the possible biotransformation and identification of the precursors has thus far not been investigated in horses. To study the possible endogenous digestive transformation, in vitro simulations of the horse hindgut were set up, using fecal inocula obtained from eight different horses. The functionality of the in vitro model was confirmed by monitoring the formation of short-chain fatty acids and the consumption of amino acids and carbohydrates throughout the digestion process. In vitro digestion samples were analyzed with a validated UHPLC-MS/MS method. The addition of ß-Bol gave rise to the formation of ADD (androsta-1,4-diene-3,17-dione) or αT. Upon addition of ADD to the in vitro digestions, the transformation of ADD to ß-Bol was observed and this for all eight horses' inocula, in line with previously obtained in vivo results, again confirming the functionality of the in vitro model. The transformation ratio proved to be inoculum and thus horse dependent. The addition of pure phytosterols (50% ß-sitosterol) or phytosterol-rich herbal supplements on the other hand, did not induce the detection of ß-Bol, only low concentrations of AED, a testosterone precursor, could be found (0.1 ng/mL). As such, the digestive transformation of ADD could be linked to the detection of ß-Bol, and the consumption of phytosterols to low concentrations of AED, but there is no direct link between phytosterols and ß-Bol.


Asunto(s)
Androstadienos/orina , Androstenodiona/orina , Digestión/fisiología , Fitosteroles/metabolismo , Testosterona/análogos & derivados , Aminoácidos/metabolismo , Anabolizantes/metabolismo , Andrógenos/metabolismo , Androstadienos/metabolismo , Androstenodiona/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Carbohidratos de la Dieta/metabolismo , Ácidos Grasos Volátiles/biosíntesis , Femenino , Caballos , Masculino , Mycobacterium/metabolismo , Esteroides/metabolismo , Espectrometría de Masas en Tándem , Testosterona/metabolismo , Testosterona/orina
7.
Chem Res Toxicol ; 23(6): 1115-26, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20507089

RESUMEN

The synthesis and structure-activity relationship studies on 5-trifluoromethylpyrido[4,3-d]pyrimidin-4(3H)-ones as antagonists of the human calcium receptor (CaSR) have been recently disclosed [ Didiuk et al. ( 2009 ) Bioorg. Med. Chem. Lett. 19 , 4555 - 4559 ). On the basis of its pharmacology and disposition attributes, (R)-2-(2-hydroxyphenyl)-3-(1-phenylpropan-2-yl)-5-(trifluoromethyl)pyrido[4,3-d]pyrimidin-4(3H)-one (1) was considered for rapid advancement to first-in-human (FIH) trials to mitigate uncertainty surrounding the pharmacokinetic/pharmacodynamic (PK/PD) predictions for a short-acting bone anabolic agent. During the course of metabolic profiling, however, glutathione (GSH) conjugates of 1 were detected in human liver microsomes in an NADPH-dependent fashion. Characterization of the GSH conjugate structures allowed insight(s) into the bioactivation pathway, which involved CYP3A4-mediated phenol ring oxidation to the catechol, followed by further oxidation to the electrophilic ortho-quinone species. While the reactive metabolite (RM) liability raised concerns around the likelihood of a potential toxicological outcome, a more immediate program goal was establishing confidence in human PK predictions in the FIH study. Furthermore, the availability of a clinical biomarker (serum parathyroid hormone) meant that PD could be assessed side by side with PK, an ideal scenario for a relatively unprecedented pharmacologic target. Consequently, progressing 1 into the clinic was given a high priority, provided the compound demonstrated an adequate safety profile to support FIH studies. Despite forming identical RMs in rat liver microsomes, no clinical or histopathological signs prototypical of target organ toxicity were observed with 1 in in vivo safety assessments in rats. Compound 1 was also devoid of metabolism-based mutagenicity in in vitro (e.g., Salmonella Ames) and in vivo assessments (micronuclei induction in bone marrow) in rats. Likewise, metabolism-based studies (e.g., evaluation of detoxicating routes of clearance and exhaustive PK/PD studies in animals to prospectively predict the likelihood of a low human efficacious dose) were also conducted, which mitigated the risks of idiosyncratic toxicity to a large degree. In parallel, medicinal chemistry efforts were initiated to identify additional compounds with a complementary range of human PK predictions, which would maximize the likelihood of achieving the desired PD effect in the clinic. The back-up strategy also incorporated an overarching goal of reducing/eliminating reactive metabolite formation observed with 1. Herein, the collective findings from our discovery efforts in the CaSR program, which include the incorporation of appropriate derisking steps when dealing with RM issues are summarized.


Asunto(s)
Anabolizantes/química , Anabolizantes/metabolismo , Osteoporosis/tratamiento farmacológico , Piridinas/química , Piridinas/metabolismo , Pirimidinonas/química , Pirimidinonas/metabolismo , Receptores Sensibles al Calcio/antagonistas & inhibidores , Anabolizantes/efectos adversos , Animales , Cristalografía por Rayos X , Humanos , Piridinas/efectos adversos , Pirimidinonas/efectos adversos , Ratas
8.
Handb Exp Pharmacol ; (195): 127-54, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20020363

RESUMEN

Nandrolone or nortestosterone, an anabolic-androgenic steroid, has been prohibited by doping control regulations for more than 30 years. Although its main metabolism in the human body was already known at that time, and detection of its misuse by gas or liquid chromatographic separation with mass spectrometric detection is straightforward, many interesting aspects regarding this doping agent have appeared since.Over the years, nandrolone preparations have kept their position among the prohibited substances that are most frequently detected in WADA-accredited laboratories. Their forms of application range from injectable fatty acid esters to orally administered nandrolone prohormones. The long detection window for nandrolone ester preparations and the appearance of orally available nandrolone precursors have changed the pattern of misuse.At the same time, more refined analytical methods with lowered detection limits led to new insights into the pharmacology of nandrolone and revelation of its natural production in the body.Possible contamination of nutritional supplements with nandrolone precursors, interference of nandrolone metabolism by other drugs and rarely occurring critical changes during storage of urine samples have to be taken into consideration when interpreting an analytical finding.A set of strict identification criteria, including a threshold limit, is applied to judge correctly an analytical finding of nandrolone metabolites. The possible influence of interfering drugs, urine storage or natural production is taken into account by applying appropriate rules and regulations.


Asunto(s)
Anabolizantes/farmacología , Doping en los Deportes , Nandrolona/farmacología , Inhibidores de 5-alfa-Reductasa , Anabolizantes/efectos adversos , Anabolizantes/análisis , Anabolizantes/metabolismo , Anabolizantes/orina , Suplementos Dietéticos , Contaminación de Medicamentos , Inhibidores Enzimáticos/farmacología , Femenino , Contaminación de Alimentos , Humanos , Masculino , Ciclo Menstrual/fisiología , Nandrolona/efectos adversos , Nandrolona/análisis , Nandrolona/metabolismo , Nandrolona/orina , Embarazo , Progestinas/farmacología
9.
Endocrinology ; 150(12): 5606-16, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19854864

RESUMEN

We identified a novel synthetic steroid, S42, as a promising candidate of selective androgen receptor (AR) modulator. Results of the whole-cell binding assay using COS-7 cells exogenously expressing various steroid receptors indicated that S42 specifically binds to AR and progesterone receptor. When orchiectomized Sprague Dawley rats were administered with S42 for 3 wk, the muscle weight of the levator ani was increased as markedly as that induced by 5alpha-dihydrotestosterone (DHT), but the weight of the prostate was not elevated at any doses in contrast to DHT. The plasma concentrations of gonadotropin and adiponectin, those down-regulated by DHT, were unaffected by S42. In addition, although the plasma triglyceride level was unaffected by DHT, it was significantly reduced by S42. This effect of S42 was associated with suppression of the SRBP-1c-mediated lipogenic and insulin-desensitizing pathway in the liver and visceral fat. Taken together, S42 works as an AR agonist in muscle and as an AR antagonist in the prostate, pituitary gland, and liver, accompanying beneficial potentials on lipid metabolism.


Asunto(s)
Próstata/metabolismo , Receptores Androgénicos/metabolismo , Esteroides/metabolismo , Células 3T3-L1 , Anabolizantes/síntesis química , Anabolizantes/metabolismo , Anabolizantes/farmacología , Antagonistas de Receptores Androgénicos , Andrógenos , Animales , Unión Competitiva , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Evaluación Preclínica de Medicamentos , Humanos , Grasa Intraabdominal/efectos de los fármacos , Grasa Intraabdominal/metabolismo , Ligandos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Estructura Molecular , Células 3T3 NIH , Orquiectomía , Tamaño de los Órganos/efectos de los fármacos , Próstata/efectos de los fármacos , Próstata/crecimiento & desarrollo , Ratas , Ratas Sprague-Dawley , Esteroides/síntesis química , Esteroides/farmacología , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Triglicéridos/sangre , Triglicéridos/metabolismo
10.
J Med Food ; 11(4): 606-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19053849

RESUMEN

As obesity rates continue to climb, there is a pressing need for novel weight loss techniques. However, the energy-restricted diets recommended for weight loss typically result in significant amounts of lean tissue loss, in addition to the desired body fat loss. Leucine, a supported anticatabolic agent, has shown promise in research at many levels. First, leucine is known to stimulate the mammalian target of rapamycin pathway, which initiates translation and protein synthesis in muscle cells. Furthermore, leucine may help to regulate blood glucose levels by promoting gluconeogenesis. Finally, several recent studies provide evidence that leucine aids in the retention of lean mass in a hypocaloric state. The aim of this paper is to review relevant leucine research in the three areas described and assess its potential as supplement for obese individuals.


Asunto(s)
Anabolizantes/metabolismo , Glucemia/metabolismo , Dieta Reductora , Leucina/metabolismo , Músculo Esquelético/metabolismo , Obesidad/dietoterapia , Tejido Adiposo/metabolismo , Suplementos Dietéticos , Homeostasis , Humanos , Obesidad/metabolismo , Transducción de Señal , Pérdida de Peso/fisiología
11.
Steroids ; 73(11): 1143-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18550137

RESUMEN

The classical analytical method for detection of anabolic steroid abuse is gas chromatography followed by mass spectrometry (GC/MS). However, even molecules with a chemical structure typical for this class of substances, are sometimes not identified in routine screening by GC/MS when their precise chemical structure is still unknown. A supplementary approach to identify anabolic steroid abuse could be a structure-independent identification of anabolic steroids based on their biological activity. To test the suitability of such a system, we have analyzed the yeast androgen receptor (AR) reporter gene system to identify anabolic steroids in human urine samples. Analysis of different anabolic steroids dissolved in buffer demonstrated that the yeast reporter gene system is able to detect a variety of different anabolic steroids and their metabolites with high specificity, including the so-called 'designer steroid' tetrahydrogestrinone. In contrast, other non-androgenic steroids, like glucocordicoids, progestins, mineralocordicoids and estrogens had a low potency to stimulate transactivation. To test whether the system would also allow the detection of androgens in urine, experiments with spiked urine samples were performed. The androgen reporter gene in yeast responds very sensitive to 5alpha-dihydrotestosterone (DHT), even at high urine concentrations. To examine whether the test system would also be able to detect anabolic steroids in the urine of anabolic steroid abusers, anonymous urine samples previously characterized by GCMS were analyzed with the reporter gene assay. Even when the concentration of the anabolic metabolites was comparatively low in some positive samples it was possible to identify the majority of positive samples by their biological activity. In conclusion, our results demonstrate that the yeast reporter gene system detects anabolic steroids and corresponding metabolites with high sensitivity even in urine of anabolic steroid abusing athletes. Therefore we believe that this system can be developed towards a powerful (pre) screening tool for the established doping tests. The system is easy to handle, robust, cost-efficient and needs no high-tech equipment. But most importantly, a biological test system does not require knowledge of the chemical structure of androgenic substances and therefore suitable to detect previously unidentified substances, especially those of the class of so-called designer steroids.


Asunto(s)
Anabolizantes/orina , Andrógenos/orina , Saccharomyces cerevisiae/metabolismo , Detección de Abuso de Sustancias/métodos , Activación Transcripcional , Anabolizantes/metabolismo , Bioensayo , Drogas de Diseño/análisis , Dihidrotestosterona/metabolismo , Dihidrotestosterona/orina , Relación Dosis-Respuesta a Droga , Genes Reporteros , Gestrinona/análogos & derivados , Gestrinona/metabolismo , Gestrinona/orina , Humanos , Masculino , Norpregnenos/metabolismo , Norpregnenos/orina , Receptores Androgénicos/efectos de los fármacos , Receptores Androgénicos/metabolismo , Saccharomyces cerevisiae/genética , Sensibilidad y Especificidad , Testosterona/análogos & derivados , Testosterona/metabolismo , Testosterona/orina , beta-Galactosidasa/metabolismo
13.
Burns ; 29(6): 592-5, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12927986

RESUMEN

PURPOSE OF REVIEW: Much of the morbidity and mortality of severely burned patients is connected with hypermetabolism and catabolism with its accompanying impairment of wound healing and increased infection risks. In order to prevent the erosion of body mass, nutritional support and other strategies to prevent catabolism have become a major focus in the care of severely burned patients. RECENT FINDINGS: Major themes discussed in recent literature are dealing with enteral versus parenteral nutrition and gastric versus duodenal feeding. The possibility of overfeeding is another important aspect of high calorie nutrition as commonly used in burned patients. Specific formulas for enteral nutrition for specific metabolic abnormalities are under evaluation as well as the role of anabolic and anticatabolic agents. SUMMARY: From the clinical literature, total enteral nutrition starting as early as possible without any supplemental parenteral nutrition is the preferred feeding method for burned patients. Using a duodenal approach, especially in the early postburn phase, seems to be superior to gastric feeding. Administration of high calorie total enteral nutrition in any later septic phase should be critically reviewed due to possible impairment of splanchnic oxygen balance. Therefore, measurement of CO(2)-gap should be considered as a monitoring method during small bowel nutrition. The impact on the course of disease of supplements such as arginine, glutamine and vitamins as well as the impact of the use of anabolic and anticatabolic agents is not yet evident. Furthermore, the effect of insulin administration and low blood sugar regimes on wound healing and outcome in burned patients should be evaluated in future studies.


Asunto(s)
Quemaduras/metabolismo , Métodos de Alimentación , Anabolizantes/metabolismo , Quemaduras/terapia , Dieta , Suplementos Dietéticos , Duodeno , Nutrición Enteral/métodos , Humanos , Nutrición Parenteral/métodos , Estómago
14.
Curr Sports Med Rep ; 1(4): 246-52, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12831702

RESUMEN

Testosterone is the primary male sex hormone, and anabolic-androgenic steroids are synthetic derivatives of testosterone. Anabolic steroids are used to enhance athletic performance and appearance. Adverse effects include those on the liver, serum lipids, psyche/behavior, and the reproductive system. Androstenedione is an anabolic-androgenic steroid used to increase blood testosterone levels for the purposes of increasing strength, lean body mass, and sexual performance. However, there is no research indicating androstenedione or its related compounds, significantly increases strength and/or lean body mass by increasing testosterone levels. The long-term health effects of prolonged androstenedione supplementation are unknown. Dehydroepiandrosterone (DHEA) is a weak androgen also used to elevate testosterone levels. DHEA is also advertised as an antiobesity and antiaging supplement capable of improving libido, vitality, and immunity levels. However, research demonstrates that DHEA supplementation does not increase serum testosterone concentrations or increase strength in men, and it may have virilizing effects on women.


Asunto(s)
Anabolizantes , Androstenodiona , Composición Corporal/efectos de los fármacos , Deshidroepiandrosterona , Músculo Esquelético/efectos de los fármacos , Deportes , Anabolizantes/efectos adversos , Anabolizantes/metabolismo , Androstenodiona/efectos adversos , Androstenodiona/metabolismo , Deshidroepiandrosterona/efectos adversos , Deshidroepiandrosterona/metabolismo , Humanos , Libido/efectos de los fármacos , Resistencia Física/efectos de los fármacos , Desempeño Psicomotor/efectos de los fármacos , Trastornos Relacionados con Sustancias/prevención & control
15.
JAMA ; 284(20): 2618-21, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11086369

RESUMEN

CONTEXT: Several anabolic steroids are sold over-the-counter (OTC) in the United States, and their production is not regulated by the US Food and Drug Administration. Reports have suggested that use of these supplements can cause positive urine test results for metabolites of the prohibited steroid nandrolone. OBJECTIVES: To assess the content and purity of OTC androstenedione and to determine if androstenedione and 19-norandrostenedione administration causes positive urine test results for 19-norandrosterone, a nandrolone metabolite. DESIGN: Randomized controlled trial of androstenedione, open-label trial of 19-norandrostenedione, and mass spectrometry of androstenedione preparations, conducted between October 1998 and April 2000. SETTING: Outpatient facility of a university hospital. PARTICIPANTS: A total of 41 healthy men aged 20 to 44 years. INTERVENTION: Participants were randomly assigned to receive oral androstenedione, 100 mg/d (n = 13) or 300 mg/d (n = 11) for 7 days, or no androstenedione (n = 13); in addition, 4 patients received 10 microg of 19-norandrostenedione. MAIN OUTCOME MEASURES: Content of OTC androstenedione preparations; level of 19-norandrosterone in urine samples, determined by mass spectrometry, compared among the 3 randomized groups at day 1 and day 7, and among the participants who received 19-norandrostenedione from October 1998 to April 2000. RESULTS: All urine samples from participants treated with androstenedione contained 19-norandrosterone, while no samples from the no-androstenedione group did. Urinary concentrations were averaged for day 1 vs day 7 measurements; mean (SD) 19-norandrosterone concentrations in the 100-mg/d and 300-mg/d groups were 3.8 (2.5) ng/mL and 10.2 (6.9) ng/mL, respectively (P =. 006). The 19-norandrosterone content exceeded the cutoff for reporting positive cases (>2.0 ng/mL) in 20 of 24. The androstenedione preparation used was pure at a sensitivity of 0.1%, but at 0.001% 19-norandrostenedione was found. For the 4 participants to whom 10 microg of 19-norandrostenedione was administered, 19-norandrosterone was found in all urine samples. Of 7 brands of androstenedione analyzed at the 1% level, 1 contained no androstenedione, 1 contained 10 mg of testosterone, and 4 more contained 90% or less of the amount stated on the label. CONCLUSION: Our study suggests that trace contamination of androstenedione with 19-norandrostenedione is sufficient to cause urine test results positive for 19-norandrosterone, the standard marker for nandrolone use. Oral steroid doses as small as 10 microg are absorbed and excreted in urine. Some brands of androstenedione are grossly mislabeled. Careful analysis of androstenedione preparations is recommended in all studies of its biological effects. JAMA. 2000;284:2618-2621.


Asunto(s)
Anabolizantes/metabolismo , Androstenodiona/análogos & derivados , Androstenodiona/metabolismo , Contaminación de Medicamentos , Estranos/orina , Nandrolona/metabolismo , Medicamentos sin Prescripción , Adulto , Androstenodiona/química , Androstenodiona/farmacología , Suplementos Dietéticos , Humanos , Masculino , Espectrometría de Masas , Detección de Abuso de Sustancias , Estados Unidos , Urinálisis
16.
Curr Opin Pediatr ; 12(4): 382-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10943821

RESUMEN

Ergogenic aids are taken to enhance energy utilization by producing more, controlling its use, or increasing mechanical efficiency. Most athletes are looking toward enhancing performance by proper training modalities and methods; however, some look to the biochemical route for a "quick fix." Thus, the use of chemical agents is on the rise. Herein is provided information on the anabolic-androgenic agents androstenedione, dehydroepiandrosterone, and the "parent" compound, testosterone. The former two, at best, have equivocal activity, but testosterone is both anabolic and androgenic in doses that adolescents might receive. Growth hormone and insulin-like growth factor-1 are anabolic, nonandrogenic compounds with undoubted effects on the lean body mass compartment. Both are expensive, not readily available, and subject to the art of counterfeiting. Thus, very few data are available in non-growth hormone-deficient adolescents. The discussion of these agents ends with issues of fairness, ethics, and the message we attempt to project to our teenagers, whether athletes or not.


Asunto(s)
Anabolizantes , Suplementos Dietéticos , Hormona de Crecimiento Humana , Adolescente , Anabolizantes/efectos adversos , Anabolizantes/metabolismo , Androstenodiona/metabolismo , Deshidroepiandrosterona/fisiología , Hormonas Esteroides Gonadales/metabolismo , Gonadotropinas/metabolismo , Hormona de Crecimiento Humana/fisiología , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Leptina/fisiología , Deportes , Testosterona/metabolismo
17.
Clin Sports Med ; 18(3): 667-89, ix, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10410848

RESUMEN

Athletes have been searching for an "edge" in competition as long as there has been a reward for success. Anabolic-androgenic steroids have been the most popular of these ergogenic aids when winning is the only goal. The authors present a concise review of these substances, their prevalence, efficacy, adverse effects, and legality. This article also presents a steroid user profile and discusses physician perception and management of a patient who uses these drugs. The popular precursors of testosterone, dehydroepiandrosterone, and androstenedione are discussed with a review of the limited available data on these substances.


Asunto(s)
Anabolizantes , Ejercicio Físico/fisiología , Deportes , Adolescente , Adulto , Anabolizantes/efectos adversos , Anabolizantes/metabolismo , Anabolizantes/farmacología , Androstenodiona , Niño , Deshidroepiandrosterona/metabolismo , Suplementos Dietéticos/efectos adversos , Femenino , Educación en Salud , Humanos , Masculino , Deportes/fisiología , Trastornos Relacionados con Sustancias/complicaciones , Estados Unidos
18.
Sports Med ; 27(2): 97-110, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10091274

RESUMEN

Nutritional strategies of overfeeding, ingesting carbohydrate/protein before and after exercise, and dietary supplementation of various nutrients [e.g. protein, glutamine, branched-chain amino acid, creatine, leucine, beta-hydroxy beta-methyl-butyrate (beta-HMB), chromium, vanadyl sulfate, boron, prasterone (dehydroepiandrosterone [DHEA]) and androstenedione] have been purported to promote gains in fat-free mass during resistance training. Most studies indicate that chromium, vanadyl sulfate and boron supplementation do not affect muscle growth. However, there is evidence that ingesting carbohydrate/protein prior to exercise may reduce catabolism during exercise and that ingesting carbohydrate/protein following resistance-exercise may promote a more anabolic hormonal profile. Furthermore, glutamine, creatine, leucine, and calcium beta-HMB may affect protein synthesis. Creatine and calcium beta-HMB supplementation during resistance training have been reported to increase fat-free mass in athletic and nonathletic populations. Prasterone supplementation has been reported to increase testosterone and fat-free mass in nontrained populations. However, results are equivocal, studies have yet to be conducted on athletes, and prasterone is considered a banned substance by some athletic organisations. This paper discusses rationale and effectiveness of these nutritional strategies in promoting lean tissue accretion during resistance training.


Asunto(s)
Suplementos Dietéticos , Desarrollo de Músculos , Músculo Esquelético/crecimiento & desarrollo , Levantamiento de Peso/fisiología , Anabolizantes/metabolismo , Boro/administración & dosificación , Boro/farmacología , Cromo/administración & dosificación , Cromo/farmacología , Creatina/administración & dosificación , Creatina/farmacología , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/farmacología , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/farmacología , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/farmacología , Glutamina/administración & dosificación , Glutamina/farmacología , Humanos , Leucina/administración & dosificación , Leucina/farmacología , Músculo Esquelético/efectos de los fármacos , Fenómenos Fisiológicos de la Nutrición , Biosíntesis de Proteínas , Testosterona/metabolismo , Valeratos/administración & dosificación , Valeratos/farmacología , Compuestos de Vanadio/administración & dosificación , Compuestos de Vanadio/farmacología
19.
Clin Sports Med ; 17(2): 299-318, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9580843

RESUMEN

A drug-control program requires testing to ensure compliance and to deter use. In the athletic drug testing area, measurement of performance-enhancing substances is complex partly because of the large number of prohibited substances. A number of sophisticated analytical techniques, such as high-resolution mass spectrometry, are increasingly used to provide the maximum detection time window. Endogenous steroids pose an increasing challenge because of their availability in "nutritional supplements". Continued vigilance is required to prevent the pharmacologic enhancement of performance.


Asunto(s)
Doping en los Deportes , Deportes , Detección de Abuso de Sustancias , Anabolizantes/metabolismo , Suplementos Dietéticos , Humanos
20.
Clin Sports Med ; 5(1): 77-89, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3512106

RESUMEN

The use of drugs to enhance athletic performance poses tremendous potential risk to amateur sport. The aquatic sports are not immune from this risk. Although the exact incidence of drug usage among aquatic athletes is not known, empirical evidence would suggest that there are indeed athletes who are using substances in an effort to enhance performance. A number of the commonly used substances have been discussed and their risks and side effects reviewed. Future success in eradicating drug usage in sport will only result from increased efforts directed at enhancement of athlete education, development of strict policies dealing with those athletes who use banned substances, and refinement of drug testing procedures.


Asunto(s)
Doping en los Deportes , Natación , Consumo de Bebidas Alcohólicas , Anfetaminas/efectos adversos , Anabolizantes/efectos adversos , Anabolizantes/metabolismo , Animales , Antiinflamatorios/efectos adversos , Transfusión de Sangre Autóloga , Cafeína/farmacología , Cocaína/efectos adversos , Humanos , Abuso de Marihuana/complicaciones , Simpatomiméticos
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