Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Physiol Behav ; 261: 114071, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584765

RESUMO

Anabolic-androgenic steroids (AAS) and caffeine can induce several behavioral alterations in humans and rodents. Administration of nandrolone decanoate is known to affect defensive responses to aversive stimuli, generally decreasing inhibitory control and increasing aggressivity but whether caffeine intake influences behavioral changes induced by AAS is unknown. The present study aimed to investigate behavioral effects of caffeine (a non-selective antagonist of adenosine receptors) alone or combined with nandrolone decanoate (one of the most commonly AAS abused) in female and male Lister Hooded rats. Our results indicated that chronic administration of nandrolone decanoate (10 mg/kg, i.m., once a week for 8 weeks) decreased risk assessment/anxiety-like behaviors (in the elevated plus maze test), regardless of sex. These effects were prevented by combined caffeine intake (0.1 g/L, p.o., ad libitum). Overall, the present study heralds a key role for caffeine intake in the modulation of nandrolone decanoate-induced behavioral changes in rats, suggesting adenosine receptors as candidate targets to manage impact of AAS on brain function and behavior.


Assuntos
Anabolizantes , Esteróides Androgênicos Anabolizantes , Decanoato de Nandrolona , Receptores Purinérgicos P1 , Animais , Feminino , Masculino , Ratos , Anabolizantes/farmacologia , Esteróides Androgênicos Anabolizantes/farmacologia , Ansiedade/induzido quimicamente , Cafeína/farmacologia , Decanoato de Nandrolona/farmacologia , Receptores Purinérgicos P1/metabolismo
2.
Steroids ; 153: 108526, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669061

RESUMO

Nandrolone decanoate (ND) is one of the most commonly abused anabolic androgenic steroids compounds in the world owing to its ability to improve physical performance but its abuse is associated with several adverse effects. The current study was performed to evaluate the effect of recommended and overdose of nandrolone decanoate (ND) for short and long term on the alterations of biochemical markers related to kidney, liver, adrenal, thyroid gland functions and oxidant and antioxidant activities. Sixty male rats were randomly assigned into two major groups. The first was treated with ND for 6 weeks and the second was treated with same drug for 12 weeks. Each of these groups was further subdivided into three sub groups: 1-Control (untreated rats), 2- Rats intraperitoneally injected with ND 3 mg/kg weekly, 3- Rats intraperitoneally injected with ND 15 mg/kg weekly. Administration of high ND dose for either short or long term significantly elevated kidney function biomarkers, liver enzymes both in serum, cytosol and mitochondria, insignificantly increased thyroid function, significantly increased adrenal function while, decreased ACTH. Moreover, oxidative stress biomarkers were significantly upregulated associated with depression in antioxidants activities. Administration of high ND dose for either short or long term as well as the repeated use of recommended ND dose for long term proved to have harmful effects manifested in impairing the functions of kidneys, liver, thyroid and adrenal glands as well as oxidant antioxidant balance.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Anabolizantes/farmacologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Decanoato de Nandrolona/farmacologia , Glândula Tireoide/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Anabolizantes/administração & dosagem , Animais , Antioxidantes/metabolismo , Biomarcadores/análise , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Rim/metabolismo , Fígado/metabolismo , Masculino , Decanoato de Nandrolona/administração & dosagem , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Glândula Tireoide/metabolismo
3.
Pharm Res ; 35(2): 41, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29404794

RESUMO

PURPOSE: The aim of this study is to use computational approaches to predict the ADME-Tox profiles, pharmacokinetics, molecular targets, biological activity spectra and side/toxic effects of 31 anabolic and androgen steroids in humans. METHODS: The following computational tools are used: (i) FAFDrugs4, SwissADME and admetSARfor obtaining the ADME-Tox profiles and for predicting pharmacokinetics;(ii) SwissTargetPrediction and PASS online for predicting the molecular targets and biological activities; (iii) PASS online, Toxtree, admetSAR and Endocrine Disruptomefor envisaging the specific toxicities; (iv) SwissDock to assess the interactions of investigated steroids with cytochromes involved in drugs metabolism. RESULTS: Investigated steroids usually reveal a high gastrointestinal absorption and a good oral bioavailability, may inhibit someof the human cytochromes involved in the metabolism of xenobiotics (CYP2C9 being the most affected) and reflect a good capacity for skin penetration. There are predicted numerous side effects of investigated steroids in humans: genotoxic carcinogenicity, hepatotoxicity, cardiovascular, hematotoxic and genitourinary effects, dermal irritations, endocrine disruption and reproductive dysfunction. CONCLUSIONS: These results are important to be known as an occupational exposure to anabolic and androgenic steroids at workplaces may occur and because there also is a deliberate human exposure to steroids for their performance enhancement and anti-aging properties.


Assuntos
Anabolizantes/farmacologia , Androgênios/farmacologia , Modelos Biológicos , Substâncias para Melhoria do Desempenho/farmacologia , Anabolizantes/química , Androgênios/química , Atletas , Simulação por Computador , Drogas Desenhadas/química , Drogas Desenhadas/farmacologia , Interações Medicamentosas , Uso Indevido de Medicamentos/efeitos adversos , Humanos , Simulação de Acoplamento Molecular , Exposição Ocupacional/efeitos adversos , Substâncias para Melhoria do Desempenho/química , Absorção Cutânea , Drogas Veterinárias/química , Drogas Veterinárias/farmacologia , Local de Trabalho
5.
J Anim Sci ; 92(3): 1219-27, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24492552

RESUMO

This research was designed to evaluate the effect of monensin (Elanco Animal Health, Greenfield, IN) supplementation via mineral or pressed protein block with or without a growth-promoting implant on performance of steers grazing wheat pasture in Arkansas over 2 yr. Preconditioned steers (n = 360, BW = 238 ± 5.1 kg) grazed 15 1.6-ha wheat pastures in the fall (n = 60 steers each fall, stocking rate of 2.5 steers/ha) or 30 0.8-ha wheat pastures in the spring (n = 120 steers each spring, stocking rate of 5 steers/ha). Steers in each pasture were given free-choice access to nonmedicated mineral (CNTRL; MoorMan's WeatherMaster Range Minerals A 646AAA; ADM Alliance Nutrition, Inc., Quincy, IL), or were supplemented with monensin (Elanco Animal Health, Greenfield, IN) via mineral containing 1.78 g monensin/kg (RMIN; MoorMan's Grower Mineral RU-1620 590AR; ADM Alliance Nutrition, Inc.), or pressed protein block containing 0.33 g monensin/kg (RBLCK; MoorMan's Mintrate Blonde Block RU; ADM Alliance Nutrition, Inc.). Additionally, one-half of the steers in each pasture were implanted (IMPL) with 40 mg trenbolone acetate and 8 mg estradiol (Component TE-G with Tylan; Elanco Animal Health). There was no interaction (P ≥ 0.71) between supplement treatment and growth-promoting implants, and ADG for RMIN and RBLCK were increased (P < 0.01) over CNTRL by 0.07 to 0.09 kg/d, respectively. Implanting steers with Component TE-G increased (P < 0.01) ADG by 0.14 kg/d. The combination of these growth-promoting technologies are a cost-effective means of increasing beef production by 22% without increasing level of supplementation or pasture acreage. Utilizing ionophores and implants together for wheat pasture stocker cattle decreased cost of gain by 26%. Utilizing both IMPL and monensin increased net return by $30 to $54/steer for RMIN or $18 to $43/steer for RBLCK compared with UNIMPL CNTRL at Low and High values of BW gain, respectively.


Assuntos
Ração Animal/análise , Criação de Animais Domésticos , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Monensin/farmacologia , Triticum/química , Anabolizantes/administração & dosagem , Anabolizantes/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Implantes de Medicamento , Estradiol/administração & dosagem , Estradiol/farmacologia , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Masculino , Estações do Ano , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia , Tilosina/administração & dosagem , Tilosina/farmacologia
6.
J Anim Sci ; 90(5): 1628-37, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22147469

RESUMO

The objectives of this study were to determine the effects of supplementation with a single ß-adrenergic agonist (ß-AA) or a sequence of ß-AA on cow performance, carcass characteristics, and mRNA relative abundance of cull cows implanted and fed a concentrate diet. Sixty cull cows were implanted with Revalor-200 (200 mg of trenbolone acetate and 20 mg of estradiol) and assigned to 1 of 4 treatments (n = 15/treatment): CON = fed a concentrate diet only; RH = supplemented with ractopamine-HCl for the last 25 d before slaughter; ZH = supplemented with zilpaterol-HCl for 20 d before a 3-d withdrawal before slaughter; RH + ZH = supplemented with RH for 25 d, followed by ZH for 20 d before a 3-d withdrawal before slaughter. Ractopamine-HCl was supplemented at a dose of 200 mg·animal(-1)·d(-1), and ZH was supplemented at 8.33 mg/kg (100% DM basis) of feed. All cows were fed a concentrate diet for 74 d. Each treatment had 5 cows per pen and 3 replicate pens. Body weights were collected on d 1, 24, 51, and 72. Muscle biopsies from the LM were collected on d 24, 51, and at slaughter from a subsample of 3 cows per pen. Carcass traits were evaluated postslaughter. The 2 ZH treatments averaged 15.3 kg more BW gain, 0.20 kg greater ADG, and 7.8 cm(2) larger LM area than CON and RH treatments, and 21 kg more HCW than CON, but these differences were not significant (P > 0.10), likely due to a sample size of n = 15/treatment. The sequence of RH followed by ZH tended to optimize the combination of HCW, LM area, percent intramuscular fat, and lean color and maturity compared with the ZH treatment. Abundance of ß(2)-adrenergic receptor (AR) mRNA was not altered in the RH + ZH treatment during RH supplementation from d 24 to 51 of feeding. However, the abundance of ß(2)-AR mRNA increased (P < 0.05) the last 23 d of feeding for the RH treatment and tended (P = 0.10) to increase in ZH cows during ZH supplementation. For all cows, abundance of type IIa myosin heavy chain (MHC-IIa) mRNA decreased (P < 0.05) after 24 d of feeding. Abundance of MHC-IIx mRNA increased (P < 0.05) for ZH and RH + ZH treatments the last 23 d of feeding during ZH supplementation. Although few significant differences were observed in performance or carcass traits, mRNA quantification indicated that ß-AA supplementation elicited a cellular response in cull cows. Implanting and feeding cull cows for 74 d, regardless of ß-AA supplementation, added economic value by transitioning cows from a cull cow to what is referred to in industry as a white cow market in which cows have white fat resulting from grain feeding.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Composição Corporal/efeitos dos fármacos , Bovinos/fisiologia , Fenetilaminas/farmacologia , RNA Mensageiro/metabolismo , Compostos de Trimetilsilil/farmacologia , Agonistas Adrenérgicos beta/administração & dosagem , Agonistas Adrenérgicos beta/economia , Anabolizantes/administração & dosagem , Anabolizantes/farmacologia , Ração Animal/economia , Animais , Combinação de Medicamentos , Estradiol/administração & dosagem , Estradiol/farmacologia , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Fenetilaminas/administração & dosagem , Fenetilaminas/economia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Adrenérgicos beta/genética , Receptores Adrenérgicos beta/metabolismo , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia , Compostos de Trimetilsilil/administração & dosagem , Compostos de Trimetilsilil/economia , Aumento de Peso
7.
West Indian med. j ; 60(5): 531-535, Oct. 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-672779

RESUMO

OBJECTIVE: Little is known about anabolic androgenic steroids (AAS) misuse in the Caribbean region in spite of increased popularity among athletes and adolescents. The present study examines the usage of AAS among competitive athletes in Puerto Rico. METHODS: Doping test results of competitive athletes obtained by random sampling out of competition during the 2000-2009 period were analysed. Doping tests were executed by the Centre for Sports, Health and Exercise Sciences (Albergue Olímpico, Salinas, Puerto Rico). A total of 550 athletes were monitored during 2000-2009. Information was collected with regard to competitive sport, gender and AAS compounds whenever a positive test result was encountered. RESULTS: From the total sample of monitored cases during the past decade, 5.4% showed adverse analytical findings. Anabolic androgenic steroids misuse was detected among male (62%) and female (38%) athletes. Weightlifting showed the greatest percentage of positive AAS doping test results (70% of total cases) and stanozolol was the most commonly misused exogenous androgen (60% of abused AAS whether alone or as part of a cocktail). Testosterone was the most common endogenous misused steroid (10% of misused compounds). CONCLUSION: In Puerto Rico, AAS misuse was detected across competitive sports for both genders. Although AAS misuse among Puerto Rican athletes shares some features that are consistent with the international sports community, it is imperative to address AAS misuse in the Caribbean region.


OBJETIVO: Poco se sabe acerca del abuso de los esteroides anabólicos androgénicos (EAA) en la región del Caribe, a pesar de su creciente popularidad entre atletas y adolescentes. El estudio presente examina el uso de EAA entre los atletas de competencia en Puerto Rico. MÉTODOS: Se analizaron los resultados de la prueba de dopaje practicada a atletas de competencia mediante un muestreo aleatorio realizado a partir de competencias celebradas durante el 2000-2009. Las pruebas de dopaje fueron realizadas por el Centro de Deportes, Salud y Ciencias del Ejercicio (Albergue Olímpico, Salinas, Puerto Rico). Se monitorearon un total de 550 atletas durante 2000-2009. Se recogió información en relación con los deportes de competencia, género, y compuestos de EAA, siempre que la prueba arrojara resultados positivos. RESULTADOS: De la muestra total de casos supervisados durante la década pasada, 5.4% mostraron resultados analíticos adversos. Se detectó un uso inapropiado de esteroides anabólicos androgénicos entre los atletas varones (62%) y hembras (38%). El levantamiento de pesas mostró el porcentaje más alto de resultados de dopaje positivos a EAA (70% del total de casos) y el estanozolol fue el andrógeno exógeno más comúnmente mal empleado (60% de los EAA usados inapropiadamente, bien solos o como parte de un cóctel). La testosterona fue el esteroide endógeno más comúnmente abusado (10% de los compuestos mal empleados). CONCLUSIÓN: En Puerto Rico, se detectó uso inapropiado de EAA en los deportes de competencia de ambos géneros. Aunque el abuso de EAA entre los atletas portorriqueños comparte algunas de las características correspondientes a la comunidad internacional de deportes, es absolutamente necesario profundizar en el problema del abuso de los EAA en el área del Caribe.


Assuntos
Adulto , Feminino , Humanos , Masculino , Anabolizantes/farmacologia , Atletas , Dopagem Esportivo/estatística & dados numéricos , Prevalência , Porto Rico/epidemiologia , Detecção do Abuso de Substâncias/métodos
8.
Anal Chim Acta ; 700(1-2): 144-54, 2011 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-21742127

RESUMO

Anabolic steroids are banned in food producing livestock in Europe. Efficient methods based on mass spectrometry detection have been developed to ensure the control of such veterinary drug residues. Nevertheless, the use of "cocktails" composed of mixtures of low amounts of several substances as well as the synthesis of new compounds of unknown structure prevent efficient prevention. New analytical tools able to detect such abuse are today mandatory. In this context, metabolomics may represent new emerging strategies for investigating the global physiological effects associated to a family of substances and therefore, to suspect the administration of steroids. The purpose of the present study was to set up, assess and compare two complementary mass spectrometry-based metabolomic strategies as new tools to screen for steroid abuse in cattle and demonstrate the feasibility of such approaches. The protocols were developed in two European laboratories in charge of residues analysis in the field of food safety. Apart from sample preparation, the global process was different in both laboratories from LC-HRMS fingerprinting to multivariate data analysis through data processing and involved both LC-Orbitrap-XCMS and UPLC-ToF-MS-MetAlign strategies. The reproducibility of both sample preparation and MS measurements were assessed in order to guarantee that any differences in the acquired fingerprints were not caused by analytical variability but reflect metabolome modifications upon steroids administration. The protocols were then applied to urine samples collected on a large group of animals consisting of 12 control calves and 12 calves administrated with a mixture of 17ß-estradiol 3-benzoate and 17ß-nandrolone laureate esters according to a protocol reflecting likely illegal practices. The modifications in urine profiles as indicators of steroid administration have been evaluated in this context and proved the suitability of the approach for discriminating anabolic treated animals from control ones. Such an approach may therefore open a new way for the screening of anabolic steroid administration through targeted monitoring of relevant biomarkers highlighted as a result of the metabolomics study.


Assuntos
Anabolizantes/farmacologia , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão/métodos , Metaboloma , Espectrometria de Massas por Ionização por Electrospray/métodos , Esteroides/farmacologia , Animais , Bovinos , Estradiol/farmacologia , Feminino , Masculino , Nandrolona/farmacologia , Detecção do Abuso de Substâncias/métodos
9.
Anat Rec (Hoboken) ; 294(2): 335-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21235008

RESUMO

In the past decades, the therapeutic use of anabolic androgenic steroids (AAS) has been overshadowed by illicit abuse of these drugs by athletes and non-athletes. Since that AAS can affect the reproductive tract, resulting in reproduction and fertilization damages, the purpose of this study was to investigate the nandrolone decanoate (ND) effects, associated or not with physical effort, on the uterine histomorphometric parameters. Female Wistar rats, sedentary or not, were exposed to treatment with ND by intraperitoneal injection (5 mg/kg/day, once a week) during four consecutive weeks. Control animals, sedentary or not, received vehicle alone (propylene glycol) in the same manner. The physical activity was forced swimming (20 min/day). During the experiment, all animals were monitored by daily vaginal smears. After 30 days of treatment, the females were sacrificed and their uteri collected and examined under light microscopy techniques. The ND-treated females showed estrus acyclicity and decreased thickness of both the epithelium and endometrial stroma. A reduction in the number and size of blood vessels was also found in ND-treated rats submitted to physical effort when compared to ND sedentary rats. ND-treated rats, regardless of exercise, exhibited stromal fibrosis and reduced gland ducts that displayed high mitotic activity. A remarkable widespread presence of leukocytes occurred in rats receiving ND and submitted to exercise. These results suggest that ND associated or not with physical effort causes histomorphometric changes to the rat uterus.


Assuntos
Anabolizantes/farmacologia , Nandrolona/análogos & derivados , Natação/fisiologia , Útero/efeitos dos fármacos , Útero/patologia , Animais , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Fibrose , Modelos Animais , Nandrolona/farmacologia , Decanoato de Nandrolona , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar , Útero/fisiopatologia
10.
West Indian Med J ; 60(5): 531-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22519228

RESUMO

OBJECTIVE: Little is known about anabolic androgenic steroids (AAS) misuse in the Caribbean region in spite of increased popularity among athletes and adolescents. The present study examines the usage of AAS among competitive athletes in Puerto Rico. METHODS: Doping test results of competitive athletes obtained by random sampling out of competition during the 2000-2009 period were analysed. Doping tests were executed by the Centre for Sports, Health and Exercise Sciences (Albergue Olímpico, Salinas, Puerto Rico). A total of 550 athletes were monitored during 2000-2009. Information was collected with regard to competitive sport, gender and AAS compounds whenever a positive test result was encountered. RESULTS: From the total sample of monitored cases during the past decade, 5.4% showed adverse analytical findings. Anabolic androgenic steroids misuse was detected among male (62%) and female (38%) athletes. Weightlifting showed the greatest percentage of positive AAS doping test results (70% of total cases) and stanozolol was the most commonly misused exogenous androgen (60% of abused AAS whether alone or as part of a cocktail). Testosterone was the most common endogenous misused steroid (10% of misused compounds). CONCLUSION: In Puerto Rico, AAS misuse was detected across competitive sports for both genders. Although AAS misuse among Puerto Rican athletes shares some features that are consistent with the international sports community, it is imperative to address AAS misuse in the Caribbean region.


Assuntos
Anabolizantes/farmacologia , Atletas , Dopagem Esportivo/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Prevalência , Porto Rico/epidemiologia , Detecção do Abuso de Substâncias/métodos
11.
Rev. bras. med. esporte ; 16(3): 191-195, maio-jun. 2010. graf, tab
Artigo em Português | LILACS | ID: lil-551078

RESUMO

O uso dos esteroides anabolizantes vem se tornando um problema de saúde pública ao longo dos últimos anos. No bojo do uso abusivo, muitos efeitos deletérios são observados, na sua totalidade por disfunções dos vários sistemas fisiológicos. Sendo assim, o objetivo do estudo foi o de avaliar o eixo hipófise-gonadal, a função hormonal, as transaminases hepáticas e o perfil de hemograma de 61 voluntários distribuídos em três grupos: 20 usuários de esteroides anabolizantes praticantes de exercício físico resistido, 21 praticantes de exercício resistido sem uso de esteroides anabolizantes e 20 sedentários. Foi observada elevação do nível de creatina quinase nos dois grupos de indivíduos que se exercitavam de maneira resistida, em relação ao grupo de sedentários (p < 0,001). Redução das gonadotrofinas LH e FSH do grupo de usuários de esteroides anabolizantes e elevação do nível de estradiol, em comparação ao grupo sedentário e treinado que não usa esteroides anabolizantes (p < 0,001). Ainda, foi observada redução da fração HDL do colesterol, em relação aos dois grupos estudados (p < 0,001). Desta maneira, o uso dos esteroides anabolizantes causa alterações bioquímicas que podem levar a instalação de efeitos colaterais.


The use of anabolic asteroids has become a public health problem over the last years. Concerning their abusive use, many deleterious effects caused in their totality by dysfunction of the various physiological systems can be observed. Therefore, the aim of the present study was to assess the hypophyseal-gonadal axis, hormone function, hepatic transaminases and hemogram profile of 61 volunteers distributed in three groups: 20 anabolic steroid users, practitioners of resisted physical exercise; 21 practitioners of resisted physical exercise with no use of anabolic steroids and 20 sedentary subjects. Increase of the creatine kinase level was observed in the two exercised groups in comparison to the sedentary group (p < 0.001). Reduction of the LH and FSH gonadotrpins of the steroid users group and increase in the estradiol level were observed in comparison to the sedentary and with no steroid use groups (p < 0.001). Moreover, reduction of the HDL cholesterol fraction was observed in comparison to the two studied groups (p < 0.001). Thus, the use of anabolic steroids causes biochemical alterations which can lead to the installation of collateral effects.


Assuntos
Humanos , Masculino , Adulto Jovem , Anabolizantes/efeitos adversos , Anabolizantes/farmacologia , Esteroides/efeitos adversos , Esteroides/farmacologia , Treinamento Resistido
12.
Drugs ; 68(18): 2709-37, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19093708

RESUMO

Recombinant teriparatide (Forteo; Forsteo) is an anabolic (bone forming) agent. Studies have shown that subcutaneous teriparatide 20 microg/day is effective in women with postmenopausal osteoporosis, men with idiopathic or hypogonadal osteoporosis and patients with glucocorticoid-induced osteoporosis. Teriparatide improves bone mineral density (BMD) and alters the levels of bone formation and resorption markers; histomorphometric studies showed teriparatide-induced effects on bone structure, strength and quality. Subcutaneous teriparatide 20 microg/day administered over a treatment period of 11-21 months was effective in reducing the risk of fractures in and in improving BMD in men with idiopathic or hypogonadal osteoporosis, women with postmenopausal osteoporosis and patients with glucocorticoid-induced osteoporosis. Furthermore, the beneficial effects of teriparatide on vertebral fracture prevention and BMD appear to persist following treatment cessation. Teriparatide is generally well tolerated and treatment compliance rates are favourable. However, current limitations on the length of treatment and the high acquisition cost mean that teriparatide is best reserved for the treatment of patients with osteoporosis at high risk of fracture, or for patients with osteoporosis who have unsatisfactory responses to or intolerance of other osteoporosis therapies.


Assuntos
Anabolizantes/uso terapêutico , Osteoporose/tratamento farmacológico , Teriparatida/uso terapêutico , Anabolizantes/economia , Anabolizantes/farmacologia , Análise Custo-Benefício , Humanos , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Osteoporose/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Teriparatida/economia , Teriparatida/farmacologia
13.
Steroids ; 73(4): 430-40, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18241900

RESUMO

This study aimed to develop a quantitative and in vivo magnetic resonance imaging (MRI) approach to investigate the muscle growth effects of anabolic steroids. A protocol of MRI acquisition on a standard clinical 1.5 T scanner and quantitative image analysis was established and employed to measure the individual muscle and organ volumes in the intact and castrated guinea pigs undergoing a 16-week treatment protocol by two well-documented anabolic steroids, testosterone and nandrolone, via implanted silastic capsules. High correlations between the in vivo MRI and postmortem dissection measurements were observed for shoulder muscle complex (R=0.86), masseter (R=0.79), temporalis (R=0.95), neck muscle complex (R=0.58), prostate gland and seminal vesicles (R=0.98), and testis (R=0.96). Furthermore, the longitudinal MRI measurements yielded adequate sensitivity to detect the restoration of growth to or towards normal in castrated guinea pigs by replacing circulating steroid levels to physiological or slightly higher levels, as expected. These results demonstrated that quantitative MRI using a standard clinical scanner provides accurate and sensitive measurement of individual muscles and organs, and this in vivo MRI protocol in conjunction with the castrated guinea pig model constitutes an effective platform to investigate the longitudinal and cross-sectional growth effects of other potential anabolic steroids. The quantitative MRI protocol developed can also be readily adapted for human studies on most clinical MRI scanner to investigate the anabolic steroid growth effects, or monitor the changes in individual muscle and organ volume and geometry following injury, strength training, neuromuscular disorders, and pharmacological or surgical interventions.


Assuntos
Anabolizantes/farmacologia , Imageamento por Ressonância Magnética/métodos , Músculos/efeitos dos fármacos , Esteroides/farmacologia , Animais , Masculino , Músculos/anatomia & histologia , Nandrolona/farmacologia , Tamanho do Órgão/efeitos dos fármacos , Suínos , Testosterona/farmacologia
14.
J Anim Sci ; 84(8): 2168-77, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16864879

RESUMO

Forty Angus-cross steers were used to evaluate 5 beef cattle management regimens for their effect on growth performance, carcass characteristics, and cost of production. A 98-d growing phase was incorporated using grass silage with or without growth promotants (trenbolone acetate + estradiol implants, and monensin in the feed) or soybean meal. Dietary treatments in the finishing phase were developed, with or without addition of the same growth promotants, based on exclusive feeding of forages with minimal supplementation or the feeding of barley-based diets. Overall, ADG for animals treated with growth promotants or fed supplemented diets (soybean meal and barley) was increased (P < 0.01) by 25 and 21%, respectively, compared with steers reared on grass silage alone and not treated with growth promotants. Except for HCW (P < 0.01), the use of growth promotants did not affect carcass measurements. Increasing the proportion of barley in the diet of steers finished on forage produced a heavier HCW (P < 0.01) and a greater (P < 0.01) quality grade. Because of their lower HCW and quality grade, cattle targeted to a forage-fed, nonimplanted beef market would need to garner a 16% premium to be economically competitive with cattle finished conventionally.


Assuntos
Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Composição Corporal/fisiologia , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Carne/normas , Aumento de Peso/fisiologia , Anabolizantes/farmacologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Estradiol/farmacologia , Hordeum/metabolismo , Ionóforos/farmacologia , Masculino , Carne/economia , Monensin/farmacologia , Poaceae , Silagem , Glycine max/metabolismo , Acetato de Trembolona/análogos & derivados , Acetato de Trembolona/farmacologia , Aumento de Peso/efeitos dos fármacos
15.
J Food Prot ; 69(6): 1256-64, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16786843

RESUMO

Eighty steers with a mean body weight of 319 kg were used in a study to evaluate the effect of a growth-promoting implant (trenbolone acetate plus estradiol benzoate), monensin, and oxytetracycline on the steer performance and shedding of some foodborne pathogens. The steers were allotted to one of eight treatment combinations according to a randomized complete block design with 16 pens of five animals. Rectal fecal samples were collected before treatment commenced and over a period of more than 24 weeks to study the influence of treatments on the intestinal microbiology of the animals. Results supported the beneficial effect of the hormonal implant on the performance of feedlot steers (average daily gain, feed efficiency, and fat thickness), on carcass characteristics (hot carcass weight, lean yield), and economic value of the carcasses (P < 0.01). The levels of Escherichia coli in feces were not affected by treatments but remained high throughout the study period. Antibiotic-resistant isolates of E. coli were more frequently found as the study progressed but were not associated with any specific treatment. Also independently of treatment, we observed a reduction over time in the shedding of Campylobacter and Yersinia during the feeding period, whereas the shedding of Enterococcus was increased. The results of this study confirmed the beneficial economic effect of growth-promoting agents in beef production and showed that the agents tested did not specifically affect the overall microbial evolution of the animal gut. However, the study also showed, independently of the growth promoter used, the shedding of Campylobacter, Yersinia, and antibiotic-resistant E. coli in the feedlot environment. These bacteria also may be found in the colonic tissue of steers at slaughter and might be a source of carcasses contamination.


Assuntos
Anabolizantes/farmacologia , Antibacterianos/farmacologia , Bovinos/crescimento & desenvolvimento , Bovinos/microbiologia , Ingestão de Alimentos , Fezes/microbiologia , Anabolizantes/administração & dosagem , Animais , Antibacterianos/administração & dosagem , Campylobacter/efeitos dos fármacos , Campylobacter/isolamento & purificação , Colo/microbiologia , Contagem de Colônia Microbiana , Análise Custo-Benefício , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/isolamento & purificação , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Monensin/administração & dosagem , Monensin/farmacologia , Oxitetraciclina/administração & dosagem , Oxitetraciclina/farmacologia , Distribuição Aleatória , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/análogos & derivados , Acetato de Trembolona/farmacologia , Aumento de Peso/efeitos dos fármacos , Yersinia/efeitos dos fármacos , Yersinia/isolamento & purificação
18.
Int J Sports Med ; 24(5): 344-51, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12868045

RESUMO

Since the abuse of androgenic-anabolic steroids (AAS) has been associated with the occurrence of serious cardiovascular disease in young athletes, we performed two studies to investigate the effects of short-term AAS administration on heart structure and function in experienced male strength athletes, with special reference to dose and duration of drug abuse. In Study 1 the effects of AAS were assessed in 17 experienced male strength athletes (age 31 +/- 7 y) who self-administered AAS for 8 or 12 - 16 weeks and in 15 non-using strength athletes (age 33 +/- 5 y) in a non-blinded design. In Study 2 the effects of administration of nandrolone decanoate (200 mg/wk i. m.) for eight weeks were investigated in 16 bodybuilders in a randomised double blind, placebo controlled design. In all subjects M-mode and two-dimensional Doppler-echocardiography were performed at baseline and after 8 weeks AAS administration. In the athletes of Study 1 who used AAS for 12 - 16 weeks a third echocardiogram was also made at the end of the AAS administration period. Echocardiographic examinations included the determination of the aortic diameter (AD), left atrium diameter (LA), left ventricular end diastolic diameter (LVEDD), interventricular septum thickness (IVS), posterior wall end diastolic wall thickness (PWEDWT), left ventricular mass (LVM), left ventricular mass index (LVMI), ejection fraction (EF) and right ventricular diameter (RVD). For assessment of the diastolic function measurements of E and A peak velocities and calculation of E/A ratio were used. In addition, acceleration and deceleration times of the E-top (ATM and DT, respectively) were determined. For evaluation of factors associated with stroke volume the aorta peak flow (AV) and left ventricular ejection times (LVET) were determined. In Study 1 eight weeks AAS self-administration did not result in changes of blood pressure or cardiac size and function. Additionally, duration of AAS self-administration did not have any impact on these parameters. Study 2 revealed that eight weeks administration of nandrolone decanoate did not induce significant alterations in blood pressure and heart morphology and function. Short-term administration of AAS for periods up to 16 weeks did not lead to detectable echocardiographic alterations of heart morphology and systolic and diastolic function in experienced strength athletes. The administration regimen used nor the length of AAS abuse did influence the results. Moreover, it is concluded that echocardiographic evaluation may provide incomplete assessment of the actual cardiac condition in AAS users since it is not sensitive enough to detect alterations at the cellular level. Nevertheless, from the present study no conclusions can be drawn of the cardiotoxic effects of long term AAS abuse.


Assuntos
Anabolizantes/farmacologia , Coração/efeitos dos fármacos , Levantamento de Peso , Adulto , Análise de Variância , Estudos de Casos e Controles , Método Duplo-Cego , Ecocardiografia , Coração/anatomia & histologia , Coração/fisiologia , Humanos , Masculino , Estudos Prospectivos , Inquéritos e Questionários
19.
Anal Chem ; 74(10): 2261-73, 2002 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12038750

RESUMO

Metabonomic characterization of long-lasting although weak physiological events such as anabolic disruptions remains poorly investigated. We have validated 1H-13C HMBC-NMR as a suitable generator of instrumental variables that are strongly linked to the concentration of endogenous metabolites in biological fluids. This method is interfaced to multivariate pattern recognition procedures. Fingerprints established from urine sample collected on cattle treated with anabolic steroids were used to validate this method. Four main results arise from this study. (i) 2D NMR is as informative as 1D NMR. (ii) 2D NMR variable clustering highlights successfully a contingent redundancy of variables, although a relevant hierarchical model of statistical correlations covering from structural relationships to physiologic links can also be evidenced. (iii) To enhance pattern recognition performances, we have validated a variable selection algorithm for accurate prediction of unknown individuals belonging to predetermined groups achieved by linear discriminant analysis (LDA). This algorithm synthesizes the whole information contained in the data set by selecting preferentially nonredundant variables. Parameters generating variable subsets are validated by predicted variance efficiency obtained when minimizing error rates calculated by cross-validation methods. (iv) Provided variables are correctly filtered, LDA fairly competes with partial least-squares methods for both classification of individuals and statistical interpretation of metabolic responses obtained in such a physiological disruption context.


Assuntos
Metabolismo , Ressonância Magnética Nuclear Biomolecular/métodos , Reconhecimento Automatizado de Padrão , Algoritmos , Anabolizantes/administração & dosagem , Anabolizantes/farmacologia , Animais , Isótopos de Carbono , Bovinos , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/metabolismo , Feminino , Masculino , Ressonância Magnética Nuclear Biomolecular/instrumentação , Prótons , Urina/química
20.
Eur J Obstet Gynecol Reprod Biol ; 98(1): 72-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11516803

RESUMO

OBJECTIVE: To assess the effect of hormone replacement therapy on neural transmission in postmenopausal women using tibolone by a non-invasive, objective way. STUDY DESIGN: In a randomised, 3 cycle, placebo-controlled study, neurovisual transmission in optic pathways were evaluated by measuring visual evoked potentials (VEP). After neuroophtalmologic examination, eligible subjects were randomised into two groups. Treatment group (n=38) were given tibolone 2.5mg daily continuously for 3 months and control group (n=20) were treated with placebo. A baseline VEP measurement before the treatment and then at the end of first, second and third month were obtained by the EMG-evoked system in the Department of Neurology, University of Celal Bayar, Manisa, Turkey. RESULTS: Data from 31 women from treatment group and 16 from control group were available for evaluation. The mean P(100) latency values, which indicate the transition time period between the optic stimuli and electrical change recorded on the occipital area by the skin electrodes, have showed a significant decrease for the study group (from 100.39+/-0.58 to 97.90+/-0.65 ms, P<0.01) at the end of the first month of treatment according to the baseline values. This difference between two groups has remained constant during the study period. CONCLUSION: The change in latency measurements of VEP, reflecting the functional status in optic pathways from retina to occipital cortex were significantly different in the treatment group than in that of control. We concluded that a facilitating effect of tibolone was observed on neurovisual transmission.


Assuntos
Anabolizantes/uso terapêutico , Potenciais Evocados Visuais/efeitos dos fármacos , Terapia de Reposição Hormonal , Norpregnenos/uso terapêutico , Pós-Menopausa , Anabolizantes/farmacologia , Feminino , Humanos , Pessoa de Meia-Idade , Norpregnenos/farmacologia , Lobo Occipital/fisiologia , Placebos , Retina/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Vias Visuais/efeitos dos fármacos , Vias Visuais/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA