Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 106
Filtrar
1.
Med Sci Monit ; 27: e934365, 2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34795200

RESUMEN

BACKGROUND Autologous blood-derived products can target specific inflammatory molecular pathways and have potentially beneficial therapeutic effects on inflammatory pathologies. The purpose of this study was to assess in vitro the anti-inflammatory and anti-catabolic potential of an autologous blood product as a possible treatment for COVID-19-induced cytokine storm. MATERIAL AND METHODS Blood samples from healthy donors and donors who had recovered from COVID-19 were incubated using different techniques and analyzed for the presence of anti-inflammatory, anti-catabolic, regenerative, pro-inflammatory, and procatabolic molecules. RESULTS The highest concentrations of therapeutic molecules for targeting inflammatory pathways were found in the blood that had been incubated for 24 h at 37°C, whereas a significant increase was observed after 6 h of incubation in blood from COVID-19-recovered donors. Beneficially, the 6-h incubation process did not downregulate anti-COVID-19 immunoglobulin G concentrations. Unfortunately, increases in matrix metalloproteinase 9, tumor necrosis factor alpha, and interleukin-1 were detected in the product after incubation; however, these increases could be blocked by adding citric acid, with no effect on the concentration of the target therapeutic molecules. Our data allow for safer and more effective future treatments. CONCLUSIONS An autologous blood-derived product containing anti-inflammatory and anti-catabolic molecules, which we term Cytorich, has a promising therapeutic role in the treatment of a virus-induced cytokine storm, including that associated with COVID-19.


Asunto(s)
Anabolizantes/sangre , Antiinflamatorios/sangre , COVID-19/complicaciones , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Adulto , Anabolizantes/aislamiento & purificación , Anabolizantes/uso terapéutico , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/uso terapéutico , COVID-19/sangre , Síndrome de Liberación de Citoquinas/etiología , Femenino , Humanos , Interleucina-1beta/antagonistas & inhibidores , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Metabolismo/efectos de los fármacos , Persona de Mediana Edad , Adulto Joven , Tratamiento Farmacológico de COVID-19
2.
Drug Test Anal ; 13(2): 386-396, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33001574

RESUMEN

Controlling the abuse of prohibited substances such as anabolic steroids, selective androgen receptor modulators, ß-adrenoceptor agonists, and blood doping agents is of great interest to racing authorities. The use of dried blood spots (DBS) as an alternative sampling approach may be a feasible approach for controlling the use of these agents. To assess the feasibility of using DBS in equine blood, an 11-min liquid chromatography-mass spectrometry method was developed on a triple quadrupole mass spectrometer following extraction from Whatman 903 DBS cards. A total of 50 compounds across multiple compound classes were detectable with reproducible results. The stability was assessed with good results after almost 3 months of storage at ambient temperatures. These results suggest that the use of DBS may be a feasible alternative sampling approach in equine drug testing.


Asunto(s)
Anabolizantes/sangre , Andrógenos/sangre , Pruebas con Sangre Seca/métodos , Caballos/sangre , Esteroides/sangre , Animales , Cromatografía Liquida/métodos , Doping en los Deportes , Límite de Detección , Espectrometría de Masas/métodos , Detección de Abuso de Sustancias/métodos
3.
J Agric Food Chem ; 68(41): 11545-11552, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32960588

RESUMEN

Serum analysis has received much attention in regulatory analysis of food-producing animals, especially for anabolic steroids. The possibility of confirming the parent drugs with minimum metabolization enables the detection of intact steroid esters, whose identification represents unequivocal proof of drug administration. This work involved the development and validation of a quantitative LC-MS/MS method to determine 30 steroids and steroid esters in bovine serum. Sensitivity was improved using microwave-assisted chemical derivatization with methoxyamine hydrochloride. The validation was successfully conducted in accordance with the Decision 657/2002/EC guidelines. An in vivo experiment was performed on 12 crossbred steers in which two commercial formulations containing boldenone undecylenate and testosterone propionate were administrated via intramuscular injections. The samples were collected over a period of 120 days, in which both intact esters were identified within 11 days postadministration. 17ß-Boldenone was observed after 92 days for 2 steers and 56 days for the other animals. The applicability of a cut-off level to the ratio between 17ß-testosterone and epitestosterone was evaluated in an attempt to differentiate testosterone abuse from endogenous production. It could be observed that a calculated ratio above this level is strong evidence of drug administration, although a high false-negative rate was obtained.


Asunto(s)
Bovinos/sangre , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Propionato de Testosterona/sangre , Testosterona/análogos & derivados , Anabolizantes/sangre , Animales , Residuos de Medicamentos/química , Masculino , Testosterona/sangre
4.
Drug Test Anal ; 12(9): 1373-1379, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32519780

RESUMEN

Selective androgen receptor modulators (SARMs) are a group of anabolic enhancer drugs posing threats to the integrity of animal sports and the safety of animal-derived foods. The current research describes for the first time the development of a semi-quantitative assay for the monitoring of SARM family compounds in blood and establishes the relative stability of these analytes under various storage conditions prior to analysis. The presented screening method validation was performed in line with current EU legislation for the inspection of livestock and produce of animal origin, with detection capability (CCß) values determined at 0.5 ng/mL (Ly2452473), 1 ng/mL (AC-262536 and PF-06260414), 2 ng/mL (bicalutamide, GLPG0492, LGD-2226, ostarine, S-1, S-6, and S-23), and 5 ng/mL (andarine, BMS-564929, LGD-4033, RAD140, and S-9), respectively. The applicability of the developed assay was demonstrated through the analysis of blood samples from racehorses and cattle. The developed method presents a high-throughput cost-effective tool for the routine screening for a range of SARM compounds in sport and livestock animals.


Asunto(s)
Anabolizantes/análisis , Andrógenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Anabolizantes/sangre , Andrógenos/sangre , Animales , Bovinos , Cromatografía Líquida de Alta Presión/economía , Análisis Costo-Beneficio , Doping en los Deportes , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Ensayos Analíticos de Alto Rendimiento/economía , Caballos , Detección de Abuso de Sustancias/economía , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem/economía
5.
Drug Test Anal ; 12(4): 514-523, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31925932

RESUMEN

The use of anabolic androgenic steroids (AAS) and other performance enhancing substances can change over time, so there is a need to constantly update what substances are used and can be detected. Six women and 30 men anabolic androgenic steroid users were recruited who filled out an anonymous questionnaire about their use of performance enhancing substances during the past year. Sampling took place on a single occasion and included blood and urine collection. Our aim was to identify which doping agents can be detected in men and women self-reporting AAS use. The first choice of substances differed between men (testosterone) and women (oxandrolone). The use of growth hormones was reported among men (10%) and women (50%). Growth hormone releasing factors/secretagogs were reported by about ~ 20% in both genders. Nandrolone was the most frequently detected anabolic androgenic steroid even in those who did not report use in the past year. Of the current male testosterone users, 82% exhibited testosterone/epitestosterone (T/E) ratios of > 4. Men with current testosterone use displayed 4-fold and 6-fold higher median T/E, respectively, when compared with recent and previous testosterone users (P = 0.0001). Dermal testosterone use in women (n = 2) was not associated with a T/E ratio of > 4, but with supra-physiological total serum testosterone concentrations. Changes in gonadotropins and hematological parameters were associated with the time of the last anabolic androgenic steroid intake in men, whereas in women these biomarkers were within the normal range. This highlights gender specific differences and indicates the need for additional biomarkers in female athletes.


Asunto(s)
Anabolizantes/sangre , Anabolizantes/orina , Andrógenos/sangre , Andrógenos/orina , Adulto , Anciano , Atletas , Doping en los Deportes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esteroides/sangre , Esteroides/orina , Detección de Abuso de Sustancias , Testosterona/sangre , Testosterona/orina , Adulto Joven
6.
J Chromatogr A ; 1613: 460686, 2020 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-31735349

RESUMEN

Being performance enhancing hormones, endogenous anabolic androgenic steroids (EAAS) are banned from most competitive sports by the World Anti-doping Agency (WADA). In anti-doping control laboratories, routine assays are mainly performed on urine samples of athletes in and out of competitions. Serum constitutes a promising alternative to urine as it is less subjected to manipulation or contamination that may influence the method sensitivity. The simultaneous determination of EAAS including conjugated metabolites using LC-MS is very challenging due to their contradicting chemical behaviors at the ionization interface of the mass spectrometer. This may prejudice their detection or limit the method sensitivity. Herein, we have addressed these challenges and developed a new method for the simultaneous determination of unconjugated, sulphate- and glucuronide-conjugated EAAS (Androsterone, Etiocholanolone, testosterone, epitestosterone, dihydrotestosterone, dehydroepiandrosterone, androstenedione and 17a-hydroxyprogesterone) in human serum using ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). The use of mass spectrometric detection in full scan mode facilitated the study of the most versatile adducts for detection and quantitation. A solid phase extraction method was developed for the sample preparation prior to analysis. The method limits of quantitation ranged from 0.006 to 7.904 ng/mL and the recoveries ranged from 70.2% to 96.5%. The method calibration was performed in untreated serum representing realistic matrix composition with correlation coeffecients ranged from 0.9859 to 0.9988. Finally, the serum-levels of the investigated steroids were determined in 4 male and 1 female human subjects to provide estimates of baseline levels based on individual values.


Asunto(s)
Cromatografía Líquida de Alta Presión , Doping en los Deportes/métodos , Espectrometría de Masas , Esteroides/sangre , Anabolizantes/sangre , Femenino , Humanos , Masculino , Extracción en Fase Sólida
7.
Drug Test Anal ; 12(1): 7-26, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31724288

RESUMEN

Within the complex construct of today's antidoping work, continuously updated routine doping controls, as well as advancements in sampling and analysis have been of particular relevance and importance. New analytes of existing classes of prohibited substances are frequently included into sports drug testing assays, analytical approaches are optimized to allow for better sensitivities, selectivity, and/or faster turnaround times, and research dedicated to addressing analytical issues concerning scenarios of both (potentially) inadvertent doping and new emerging doping agents is constantly conducted. By way of reviewing and summarizing, this annual banned-substance review evaluates the literature published between October 2018 and September 2019 offering an in-depth evaluation of developments in these arenas and their potential application to substances reported in WADA's 2019 Prohibited List.


Asunto(s)
Doping en los Deportes , Detección de Abuso de Sustancias/métodos , Anabolizantes/análisis , Anabolizantes/sangre , Anabolizantes/orina , Animales , Hormonas/análisis , Hormonas/sangre , Hormonas/orina , Humanos , Péptidos y Proteínas de Señalización Intercelular/análisis , Péptidos y Proteínas de Señalización Intercelular/sangre , Péptidos y Proteínas de Señalización Intercelular/orina , Espectrometría de Masas/métodos , Sustancias para Mejorar el Rendimiento/análisis , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Manejo de Especímenes/métodos , Esteroides/análisis , Esteroides/sangre , Esteroides/orina
8.
J Anim Sci ; 97(11): 4371-4385, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31541251

RESUMEN

Predominately Angus steers (n = 24; initial BW = 435 ± 28.3 kg) were used to evaluate non-coated (NC) and coated implants (CI) containing equal amounts of trenbolone acetate (TBA; 200 mg) and estradiol benzoate (EB; 28 mg) in finishing steers on sera metabolite responses, gene expression, and immunohistochemical analyses of the Longissimus muscle (LM). Performance data were analyzed as a randomized complete block design, and all other data were analyzed as repeated measures for a completely randomized design. Treatments were no implant (NI), NC (Synovex-PLUS; Zoetis, Parsippany, NJ), and CI (Synovex-One Feedlot) implant. There were 2 pen replicates per treatment (n = 4 steers/pen). LM biopsies, blood, and BW were collected before feeding on days 0, 14, 28, 56, 84, 112, and 133, with final BW being captured on day 140. Genes of interest were determined by RT-qPCR using two housekeeping genes. Sera was analyzed for estradiol-17ß (E2),17ß-trenbolone (TbOH), insulin-like growth factor 1 (IGF-I), NEFA, and urea-N (SUN). An α of 0.10 determined significance for performance and sera data; α of 0.05 was used for gene and histology data. No performance differences (P ≥ 0.10) were detected. An implant × day interaction (P ≤ 0.10) for E2, IGF-I, and SUN was detected; implants elevated (P ≤ 0.10) E2, 17ß-TbOH, and IGF-I; and decreased SUN across day of the study, meaning sera metabolites are not altered with time on feed. An implant × day interaction was detected for myogenic factor 5 (MYF-5) positive cells and proportions of MHCIIX. In LM, CI had greater (P < 0.10) IGF-I in LM over NI. CI increased (P < 0.05) G protein-coupled estrogen receptor 1 (GPER1) expression, as well as, GPER1 semi-quantitative scores over NI and NC. An implant × day interaction (P ≤ 0.05) for estrogen and androgen receptor-positive nuclei was detected; implants had increased (P ≤ 0.05) estrogen and androgen receptor-positive nuclei compared to NI. CIs increase genes associated with muscle tissue growth.


Asunto(s)
Anabolizantes/administración & dosificación , Bovinos/fisiología , Estradiol/análogos & derivados , Esteroides/administración & dosificación , Acetato de Trembolona/administración & dosificación , Anabolizantes/sangre , Alimentación Animal , Animales , Bovinos/sangre , Dieta/veterinaria , Implantes de Medicamentos/administración & dosificación , Ingestión de Alimentos , Estradiol/administración & dosificación , Estradiol/sangre , Inmunohistoquímica/veterinaria , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Músculo Esquelético/metabolismo , Distribución Aleatoria , Carne Roja/análisis , Acetato de Trembolona/sangre
9.
J Clin Endocrinol Metab ; 104(7): 2490-2500, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30753550

RESUMEN

CONTEXT: The lifetime prevalence of anabolic androgenic steroid (AAS) use is estimated at 1% to 5% worldwide. AAS use occurs primarily male elite athletes and men who want a muscular appearance. The evidence for effective, safe management of AAS cessation and withdrawal is weak. DESIGN: Key studies were extracted from PubMed (1990-2018) and Google Scholar with reference searches from relevant retrieved articles. RESULTS: The proven adverse effects of AASs include suppression of the gonadal axis and infertility, hirsutism and defeminization in women, and erythrocytosis. Alkylated AASs that are taken orally may cause hepatopathy. There is an association between high-dosage AAS use and increased risk of cardiovascular disease. Clues for AAS use include very low serum high-density cholesterol and sex hormone-binding globulin concentrations and unexplained erythrocytosis. For elite athletes, the biological passport (monitoring of blood or urinary androgen and androgen precursor concentrations after determining the athlete's baseline) is useful for detecting AAS use. For nonelite athletes, the best method to confirm AAS use is to inquire in a nonjudgmental manner. Cessation of chronic AAS use is associated with a withdrawal syndrome of anxiety and depression. CONCLUSIONS: Men who use AASs <1 year typically recover normal hypothalamic-pituitary-testicular axis function within 1 year after cessation. Men who have infertility due to high-dosage AAS use ≥1 year might benefit from short-term treatment with clomiphene or human chorionic gonadotropin.


Asunto(s)
Anabolizantes/efectos adversos , Andrógenos/efectos adversos , Sustancias para Mejorar el Rendimiento/efectos adversos , Detección de Abuso de Sustancias/métodos , Trastornos Relacionados con Sustancias/diagnóstico , Anabolizantes/administración & dosificación , Anabolizantes/sangre , Anabolizantes/orina , Andrógenos/administración & dosificación , Andrógenos/sangre , Andrógenos/orina , Atletas/legislación & jurisprudencia , Doping en los Deportes/legislación & jurisprudencia , Doping en los Deportes/prevención & control , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Prevalencia , Factores Sexuales , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/etiología , Trastornos Relacionados con Sustancias/terapia
10.
J Clin Endocrinol Metab ; 103(9): 3215-3224, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29982690

RESUMEN

Context: GlaxoSmithKline (GSK) 2881078 is a nonsteroidal, selective androgen receptor modulator (SARM) under investigation by GSK for treatment of reduced mobility and other functional limitation in men and women with muscle weakness associated with chronic and acute illnesses. Objective: This was a phase 1b study intended to explore across a dose range the pharmacokinetics (PK)-pharmacodynamics relationship and further safety and tolerability data for GSK2881078. This study also evaluated effects of CYP3A4 inhibition on PK of GSK2881078. Methods: This was a randomized, placebo-controlled, parallel-group, repeat-dose, dose-escalation study in healthy older males and postmenopausal females. A total of three cohorts of males and three cohorts of females were studied. Dosing at each dose level was twice daily for the first 3 days followed by once daily for up to 53 days. Repeated dual-energy X-ray absorptiometry and MRI cross-sectional thigh scans were performed. The effect of CYP3A4 inhibition on GSK2881078 PK was evaluated in a separate cohort. Results: GSK2881078 was generally well tolerated and no serious adverse events were reported. Compared with placebo, there was greater lean mass accrual with all dose levels of GSK2881078. Females exhibited a greater response at lower doses than did males. Transient elevations of alanine aminotransferase were observed. The effect of CYP3A4 inhibition on GKS2881078 PK was unlikely to be of clinical significance. Conclusions: GSK2881078 yielded dose-dependent increases in lean mass with evidence of enhanced sensitivity in women. The compound was well tolerated.


Asunto(s)
Anabolizantes/administración & dosificación , Composición Corporal/efectos de los fármacos , Indoles/administración & dosificación , Absorciometría de Fotón/métodos , Anciano , Anabolizantes/efectos adversos , Anabolizantes/sangre , Anabolizantes/farmacología , Composición Corporal/fisiología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Semivida , Voluntarios Sanos , Hormonas/sangre , Humanos , Indoles/efectos adversos , Indoles/sangre , Indoles/farmacología , Lípidos/sangre , Masculino , Persona de Mediana Edad , Caracteres Sexuales
11.
CPT Pharmacometrics Syst Pharmacol ; 7(4): 259-268, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29436172

RESUMEN

A randomized, double-blind clinical trial was conducted to investigate long-term abuse effects of testosterone cypionate (TC). Thirty-one healthy men were randomized into a dose group of 100, 250, or 500 mg/wk and received 14 weekly injections of TC. A pharmacokinetic/pharmacodynamic (PK/PD) model was developed to characterize testosterone concentrations and link exposure to change in luteinizing hormone and spermatogenesis following long-term TC administration. A linear one-compartment model best described the concentration-time profile of total testosterone. The population mean estimates for testosterone were 2.6 kL/day for clearance and 14.4 kL for volume of distribution. Weight, albumin, and their changes from baseline were identified as significant covariates for testosterone. The estimated potency of total testosterone (tT) with respect to suppression of luteinizing hormone (LH) synthesis was 9.33 ng/mL. Simulation based on the indirect response model suggests the suppression of endogenous testosterone secretion, LH synthesis, and spermatogenesis was more severe and of greater duration in the 250 mg and the 500 mg dose groups.


Asunto(s)
Anabolizantes/farmacología , Andrógenos/farmacología , Modelos Biológicos , Testosterona/análogos & derivados , Adulto , Anabolizantes/administración & dosificación , Anabolizantes/sangre , Andrógenos/administración & dosificación , Andrógenos/sangre , Método Doble Ciego , Voluntarios Sanos , Humanos , Hormona Luteinizante/sangre , Masculino , Espermatogénesis/efectos de los fármacos , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/farmacología , Adulto Joven
12.
Curr Opin Crit Care ; 24(2): 124-130, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29389741

RESUMEN

PURPOSE OF REVIEW: Skeletal muscle mass with aging, during critical care, and following critical care is a determinant of quality of life and survival. In this review, we discuss the mechanisms that underpin skeletal muscle atrophy and recommendations to offset skeletal muscle atrophy with aging and during, as well as following, critical care. RECENT FINDINGS: Anabolic resistance is responsible, in part, for skeletal muscle atrophy with aging, muscle disuse, and during disease states. Anabolic resistance describes the reduced stimulation of muscle protein synthesis to a given dose of protein/amino acids and contributes to declines in skeletal muscle mass. Physical inactivity induces: anabolic resistance (that is likely exacerbated with aging), insulin resistance, systemic inflammation, decreased satellite cell content, and decreased capillary density. Critical illness results in rapid skeletal muscle atrophy that is a result of both anabolic resistance and enhanced skeletal muscle breakdown. SUMMARY: Insofar as atrophic loss of skeletal muscle mass is concerned, anabolic resistance is a principal determinant of age-induced losses and appears to be a contributor to critical illness-induced skeletal muscle atrophy. Older individuals should perform exercise using both heavy and light loads three times per week, ingest at least 1.2 g of protein/kg/day, evenly distribute their meals into protein boluses of 0.40 g/kg, and consume protein within 2 h of retiring for sleep. During critical care, early, frequent, and multimodal physical therapies in combination with early, enteral, hypocaloric energy (∼10-15 kcal/kg/day), and high-protein (>1.2 g/kg/day) provision is recommended.


Asunto(s)
Cuidados Críticos , Enfermedad Crítica/terapia , Ingestión de Energía/fisiología , Nutrición Enteral , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/fisiopatología , Anabolizantes/sangre , Protocolos Clínicos , Humanos , Atrofia Muscular/prevención & control , Necesidades Nutricionales
13.
Nutr Hosp ; 34(5): 1155-1162, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-29130715

RESUMEN

INTRODUCTION: Specific macronutrient distribution and training can alter acute and chronic hormone behavior and, subsequently, sport performance. OBJECTIVE: The main aim was to examine relationships between dietary intake and anabolic/catabolic hormone response in elite female volleyball players during a 29-week season. METHODS: Twenty-two elite female volleyballers (26.4 ± 5.6 years; 178 ± 9 cm; 67.1 ± 7.5 kg) had dietary intake (seven-day dietary recall and food frequency questionnaire), blood concentration of anabolic/catabolic hormones concentration, physical performance, and body composition assessed at four time points: a) T1: baseline/pre-testing; b) T2: eleven weeks after T1; c) T3: ten weeks after T2; and d) T4: eight weeks after T3. Hormones evaluated were: total testosterone (TT), free testosterone (FT) adrenocorticotropic hormone (ACTH), and cortisol (C), along with hormone ratios. RESULTS: Positive correlations were observed between carbohydrate/protein ratio with ΔFT (r = 0.955; p < 0.001), ΔTT/C ratio (r = 0.638; p = 0.047), and ΔFT/C ratio (r = 0.909; p < 0.001). Significant and negative correlations were found between protein intake with ΔTT (r = -0.670; p = 0.034), and FT (r = -0.743; p < 0.001), carbohydrate intake and ΔACTH (r = -0.658; p = 0.006). No relationships were observed regarding Δcortisol. On the other hand, there was no change (p > 0.05) in body mass or body mass index at any time point, and the sum of six skinfolds improved (p < 0.05) from T1 (86.5 ± 6.9 mm) to T4 (75.2 ± 5.6 mm) as did muscle mass (T1: 28.9 ± 0.7 kg vsT4: 30.1 ± 0.8 kg). Vertical jump, spike-jump and speed improved (p < 0.05) from T1 to T4. CONCLUSIONS: A high carbohydrate/protein ratio was associated with positive changes in anabolism, while high protein and low carbohydrates (CHO) were associated with an attenuated anabolic response.


Asunto(s)
Atletas , Hormonas/sangre , Voleibol/fisiología , Adulto , Anabolizantes/sangre , Rendimiento Atlético/fisiología , Composición Corporal , Dieta , Carbohidratos de la Dieta , Proteínas en la Dieta , Femenino , Humanos , Adulto Joven
14.
Clin Sci (Lond) ; 131(21): 2643-2653, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28982725

RESUMEN

Leucine modulates muscle protein synthesis (MPS), with potential to facilitate accrual/maintenance of muscle mass. Animal models suggest that leucine boluses shortly after meals may prolong MPS and delay onset of a "muscle-full" state. However, the effects of nutrient "top-ups" in humans, and particularly older adults where deficits exist, have not been explored. We determined the effects of a leucine top-up after essential amino acid (EAA) feeding on anabolic signaling, MPS, and muscle energy metabolism in older men. During 13C6-phenylalanine infusion, 16 men (∼70 years) consumed 15 g of EAA with (n=8, FED + LEU) or without (n=8, FED) 3 g of leucine top-up 90 min later. Repeated blood and muscle sampling permitted measurement of fasting and postprandial plasma EAA, insulin, anabolic signaling including mTOR complex 1 (mTORC1) substrates, cellular ATP and phosphorylocreatine, and MPS. Oral EAA achieved rapid insulinemia (12.5 iU·ml-1 25 min post-feed), essential aminoacidemia (3000 µM, 45-65 min post-feed), and activation of mTORC1 signaling. Leucine top-up prolonged plasma EAA (2800 µM, 135 min) and leucine availability (1050 µM, 135 min post-feed). Fasting FSRs of 0.046 and 0.056%·h-1 (FED and FED + LEU respectively) increased to 0.085 and 0.085%·h-1 90-180 min post-feed and returned to basal rates after 180 min in both groups. Phosphorylation of mTORC1 substrates returned to fasting levels 240 min post-feed in both groups. Feeding had limited effect on muscle high-energy phosphates, but did induce eukaryotic elongation factor 2 (eEF2) phosphorylation. We demonstrate the refractoriness of muscle to nutrient-led anabolic stimulation in the postprandial period; thus, leucine supplements should be taken outside of meals, or with meals containing suboptimal protein in terms of either amount or EAA composition.


Asunto(s)
Envejecimiento/metabolismo , Anabolizantes/administración & dosificación , Suplementos Dietéticos , Metabolismo Energético/efectos de los fármacos , Leucina/administración & dosificación , Músculo Esquelético/efectos de los fármacos , Periodo Posprandial , Biosíntesis de Proteínas/efectos de los fármacos , Adenosina Trifosfato/metabolismo , Factores de Edad , Anciano , Envejecimiento/sangre , Anabolizantes/sangre , Humanos , Insulina/sangre , Leucina/sangre , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina , Complejos Multiproteicos/metabolismo , Músculo Esquelético/metabolismo , Fosfocreatina/metabolismo , Fosforilación , Estudios Prospectivos , Factores Sexuales , Serina-Treonina Quinasas TOR/metabolismo , Factores de Tiempo
15.
Molecules ; 22(6)2017 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-28604639

RESUMEN

In vitro studies show that diclofenac inhibits enzymatic steroid glucuronidation. This study was designed to investigate the influence of diclofenac on the excretion of stanozolol and 3'-hydroxystanozolol via analyses in hair, blood and urine in vivo in a rat study. Brown Norway rats were administered with stanozolol (weeks 1-3) and diclofenac (weeks 1-6). Weekly assessment of steroid levels in hair was complemented with spot urine and serum tests. Levels of both stanozolol and 3'-hydroxystanozolol steadily increased in hair during stanozolol treatment and decreased post-treatment, but remained readily detectable for 6 weeks. In contrast, compared to control rats, diclofenac significantly reduced urinary excretion of 3'-hydroxystanozolol which was undetectable in most samples. This is the first report of diclofenac altering steroid metabolism in vivo, detrimentally affecting detection in urine, but not in hair, which holds considerable advantages over urinalysis for anti-doping tests.


Asunto(s)
Diclofenaco/efectos adversos , Doping en los Deportes , Esteroides/metabolismo , Detección de Abuso de Sustancias/métodos , Anabolizantes/sangre , Animales , Diclofenaco/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Glucurónidos/metabolismo , Cabello/química , Humanos , Ratas , Estanozolol/análogos & derivados , Estanozolol/sangre , Estanozolol/orina
16.
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
17.
Mil Med ; 182(3): e1810-e1818, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28290964

RESUMEN

INTRODUCTION: In Estonian Defense Forces that are drawn up on the basis of the conscription model considerable numbers of young men are prematurely discharged from military service for medical reasons, but causes leading to premature dropout of conscripts have not been systematically studied. However, one of the factors involved could be relatively demanding physical training that starts at the beginning of military service in the form of basic military training (BMT). Cumulative training and nontraining stresses experienced by conscripts during BMT may exceed their physiological adaptability and increase the probability of becoming prematurely discharged. Therefore, the primary purpose of this study was to assess physiological responses to 10-week BMT in Estonian conscripts. MATERIALS AND METHODS: The protocol of the study confirmed to the standards set by the Declaration of Helsinki and it was approved by the Research Ethics Committee of the University of Tartu. Mean ± SD age and body mass index of 94 conscripts studied was 20.9 ± 1.7 years and 24.2 ± 3.0 kg · m-2, respectively. Fasting venous blood analysis was performed four times during BMT (October to December) and once 15 weeks after the end of BMT (in March). One-factor (time) repeated measures analysis of variance was used to evaluate the differences within the variables. Statistical significance was set at p < 0.05. Where a significant main effect was observed, Tukey's honesty significant difference post-hoc analysis was used to locate differences between the means. A Pearson product moment coefficient of correlation (r) with α level set at 0.05 was applied to determine the relationship between variables. RESULTS: Significant increases in serum testosterone concentration (60.6%), testosterone to cortisol ratio (61.1%), blood erythrocyte count (4.3%), hemoglobin concentration (3.8%) and hematocrit (2.2%), and decrease in serum ferritin concentration (39.3%) occurred between weeks 1 and 10 during BMT (in all cases p < 0.0001). Fifteen weeks later, these parameters were still at increased or decreased levels, respectively, compared to week 1. The prevalence of vitamin D deficiency (serum 25(OH) D concentration <50 nmol · L-1) increased from 42.6% in week 1 to 80.8% in week 10 and to 91.5% 15 weeks later. Serum 25(OH)D levels did not correlate with testosterone concentrations (r = 0.062, p = 0.552 in Wk-1 and r = -0.079, p = 0.448 in Wk-25). CONCLUSION: These findings suggest that BMT induces anabolic physiological adaptations in conscripts despite vitamin D deficiency and decrease in iron status. However, high prevalence of vitamin D deficiency and decline in iron status may limit physiological adaptations and improvement in physical work capacity to a suboptimal level. Furthermore, as vitamin D influences a variety of functions important for health, deficiency in conscripts should be considered a major concern that needs treatment. An acknowledged limitation of the study is the lack of a control group of conscripts possessing normal vitamin D status and stable serum ferritin levels throughout the study period. Nevertheless, the research design employed enabled to determine two factors that potentially limit physiological adaptability of conscripts to military training loads in ecologically authentic environment.


Asunto(s)
Anabolizantes/análisis , Personal Militar/estadística & datos numéricos , Prevalencia , Deficiencia de Vitamina D/complicaciones , Adolescente , Anabolizantes/sangre , Análisis de Varianza , Índice de Masa Corporal , Educación/tendencias , Recuento de Eritrocitos , Estonia , Hematócrito , Hemoglobinas/análisis , Humanos , Hidrocortisona/análisis , Hidrocortisona/sangre , Hierro/análisis , Hierro/sangre , Estudios Longitudinales , Masculino , Aptitud Física , Testosterona/análisis , Testosterona/sangre , Adulto Joven
18.
Artículo en Inglés | MEDLINE | ID: mdl-28346887

RESUMEN

Recently, steroid hormones quantification in blood showed a promising ability to detect testosterone doping and interesting complementarities with the urinary module of the Athlete Biological Passport (ABP). In this work, an ultra-high pressure liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) method was developed for the quantification of eleven endogenous steroids in serum. The performance of the full scan and targeted SIM acquisition modes was evaluated and compared to the performance of tandem mass spectrometry (MS/MS). Passing-Bablok regressions and Bland-Altman plots were assessed for each analyte of interest, and concentration values measured by HRMS showed high correlation with the ones obtained by MS/MS for all target hormones, with low absolute differences in the majority of cases. A slight decrease in terms of sensitivity was observed with HRMS in both acquisition modes, but performing an analysis of variance multiblock orthogonal partial least squares (AMOPLS) on the dataset obtained with all three methods revealed that only 0.8% of the total variance was related to instrumentation and acquisition methods. Moreover, the evaluation of the testosterone administration effect over time highlighted testosterone itself and dihydrotestosterone as the most promising biomarkers of exogenous testosterone administration. This conclusion suggests that HRMS could provide suitable performance for blood steroid analysis in the anti-doping field.


Asunto(s)
Anabolizantes/sangre , Cromatografía Líquida de Alta Presión/métodos , Esteroides/sangre , Espectrometría de Masas en Tándem/métodos , Testosterona/sangre , Dihidrotestosterona/sangre , Doping en los Deportes , Humanos , Límite de Detección , Masculino , Espectrometría de Masas/métodos
19.
Clin Nutr ; 36(6): 1716-1719, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28017449

RESUMEN

BACKGROUND: Ageing and type 2 diabetes mellitus (T2DM) are risk factors for skeletal muscle loss. We investigated whether anabolic resistance to feeding might underlie accelerated muscle loss in older people with T2DM and whether dysregulated mTOR signalling was implicated. SUBJECTS: 8 obese men with T2DM, and 12 age-matched controls were studied (age 68 ± 3 vs. 68±6 y; BMI: 30 ± 2 vs. 27 ± 5 kg m-2). METHODS: Body composition was measured by dual-X-ray absorptiometry. Insulin and glucose were clamped at post-absorptive concentrations (13 ± 2 vs. 9 ± 3 mU l-1; 7.4 ± 1.9 vs. 4.6 ± 0.4 mmol l-1; T2DM vs. controls). Fractional synthetic rates (FSR) of myofibrillar and sarcoplasmic proteins were measured as the rate of incorporation of [13C] leucine during a primed, constant infusion of [1-13C] α-ketoisocaproic acid, 3 h after 10 or 20 g of essential amino acids (EAA) were orally administered. Protein expression of total and phosphorylated mTOR signalling proteins was determined by Western blot analysis. RESULTS: Despite a significantly lower appendicular lean mass index and a greater fat mass index in T2DM vs. controls, basal myofibrillar and sarcoplasmic and post-prandial myofibrillar FSR were similar. After 20 g EAA, stimulation of sarcoplasmic FSR was slightly blunted in T2DM patients. Furthermore, feeding 20 g EAA increased phosphorylation of mTOR, p70S6k and 4E-BP1 by 60-100% in controls with no response observed in T2DM. CONCLUSIONS: There was clear dissociation between changes in mTOR signalling versus changes in protein synthesis rates. However, the intact anabolic response of myofibrillar FSR to feeding in both groups suggests anabolic resistance may not explain accelerated muscle loss in T2DM.


Asunto(s)
Anabolizantes/administración & dosificación , Diabetes Mellitus Tipo 2/complicaciones , Sarcopenia/etiología , Serina-Treonina Quinasas TOR/metabolismo , Absorciometría de Fotón , Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Anciano , Aminoácidos Esenciales/administración & dosificación , Aminoácidos Esenciales/sangre , Anabolizantes/sangre , Glucemia/metabolismo , Composición Corporal , Índice de Masa Corporal , Estudios de Casos y Controles , Proteínas de Ciclo Celular , Diabetes Mellitus Tipo 2/sangre , Humanos , Insulina/sangre , Cetoácidos/administración & dosificación , Cetoácidos/sangre , Leucina/administración & dosificación , Leucina/sangre , Masculino , Persona de Mediana Edad , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Obesidad/sangre , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Obesidad/genética , Fosfoproteínas/antagonistas & inhibidores , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilación , Periodo Posprandial , Biosíntesis de Proteínas , Proteínas Quinasas S6 Ribosómicas 70-kDa/antagonistas & inhibidores , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Factores de Riesgo , Sarcopenia/sangre , Transducción de Señal
20.
Int J Pharm ; 515(1-2): 721-728, 2016 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-27989828

RESUMEN

Long-term therapy of nandrolone (N) is recommended to increase mineral density and muscle strength. Using a parenteral sustained release drug formulation with nandrolone decanoate (ND), therapeutic N levels can be achieved and maintained. Until now, it is unknown if hydrolysis of ND into N occurs in tissue at the injection site or after systemic absorption. Therefore, hydrolysis studies were conducted to investigate the location and rate of ND hydrolysis after its release from the oil depot. ND hydrolysis was studied in porcine tissues, to mimic the human muscular and subcutaneous tissues. Additionally, the ND hydrolysis was studied in human whole blood, plasma and serum at a concentration range of 23.3-233.3µM. ND hydrolysis only occurred in human whole blood. The hydrolysis did not start immediately, but after a lag time. The mean lag time for all studied concentrations was 34.9±2.5min. Because of a slow penetration into tissue, hydrolysis of ND is found to be very low in surrounding tissue. Therefore the local generation of the active compound is clinically irrelevant. It is argued that after injection of the oil depot, ND molecules will be transported via the lymphatic system towards lymph nodes. From here, it will enter the central circulation and within half an hour it will hydrolyse to the active N compound.


Asunto(s)
Nandrolona/análogos & derivados , Anabolizantes/administración & dosificación , Anabolizantes/sangre , Anabolizantes/farmacocinética , Animales , Líquidos Corporales/metabolismo , Bovinos , Preparaciones de Acción Retardada , Liberación de Fármacos , Humanos , Hidrólisis , Músculo Esquelético/metabolismo , Nandrolona/administración & dosificación , Nandrolona/sangre , Nandrolona/farmacocinética , Nandrolona Decanoato , Porcinos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...