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The non-psychoactive cannabinoids cannabidiol (CBD) and cannabidiolic acid (CBDA) are available on the market in different forms, mostly for their anti-inflammatory and potential analgesic properties. These substances are prohibited during equine competitions. CBD and CBDA are naturally present in hemp straw, commonly used as a bedding substitute for wheat straw. Unfortunately, horses can eat it, which therefore could lead to a possible risk of positive findings for CBD/CBDA in biological samples after doping control tests. The goals of this study were, first, to provide recommendations on the use of hemp straw before competition and, second, to assess if discrimination between hemp bedding exposure and CBD oil administration is possible. Several CBD equine in vivo studies have been conducted, including one on hemp straw used as bedding and one after administration of CBD oil by topical and sublingual routes. In hemp straw, CBDA was detected in higher quantities than CBD, and other cannabinoids have been observed. After hemp straw exposure, CBDA was also detected in higher quantities than CBD in all urine samples. It appeared that hemp straw should not be used as bedding for equine competition except if a delay of at least 48 h is respected. Regarding the CBD oil product analysis, CBD was the main compound detected. After administration, 7-hydroxy CBD was identified in the urine. In conclusion, based on these data, we highlighted that it could be possible to discriminate the exposure of a horse to hemp straw from an administration of a CBD oil product thanks to the main presence of CBDA.
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Clodronic acid is designated as a controlled medication for competition horses by the International Federation for Equestrian Sports and, according to the International Federation of Horseracing Authorities, clodronic acid is not to be administered to racehorses younger than 3.5 years or within 30 days prior to a race. In this study, 35 horses involved in competition were treated with a single dose of 1.53 mg clodronic acid/kg bodyweight intramuscularly. Plasma samples were obtained before treatment and 10, 20, 30, and 40 days post-administration. Clodronic acid concentrations were measured using a validated method, and the data were fitted using a nonlinear mixed effects model. The estimated depletion half-life of clodronic acid was 10.6 days (inter-individual variability: 17.9%). Age, body weight, sex, disease severity, dose, training days, training, and competition did not significantly impact the depletion half-life. The percentage of horses predicted via simulation to have clodronic acid concentrations below the assay's limit of quantification of 1.0 ng/mL was 93.9% at day 30 and 99.4% at Day 40. This study provides rationale to the equestrian federations and horse racing authorities to reliably establish a detection time for clodronic acid, assisting equine veterinarians in recommending a competition withdrawal time for the horses under their care.
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Many innovative biotherapeutics have been marketed in the last decade. Monoclonal antibodies (mAbs) and Fc-fusion proteins (Fc-proteins) have been developed for the treatment of diverse diseases (cancer, autoimmune diseases, and inflammatory disorders) and now represent an important part of targeted therapies. However, the ready availability of such biomolecules, sometimes characterized by their anabolic, anti-inflammatory, or erythropoiesis-stimulating properties, raises concerns about their potential misuse as performance enhancers for human and animal athletes. In equine doping control laboratories, a method has been reported to detect the administration of a specific human biotherapeutic in equine plasma; but no high-throughput method has been described for the screening without any a priori knowledge of human or murine biotherapeutic. In this context, a new broad-spectrum screening method involving UHPLC-HRMS/MS has been developed for the untargeted analysis of murine or human mAbs and related macromolecules in equine plasma. This approach, consisting of a "pellet digestion" strategy performed in a 96-well plate, demonstrates reliable performances at low concentrations (pmol/mL range) with high-throughput capability (≈100 samples/day). Targeting species-specific proteotypic peptides located within the constant parts of mAbs enables the "universal" detection of human biotherapeutics only by monitoring 10 peptides. As proof of principle, this strategy successfully detected different biotherapeutics in spiked plasma samples, and allowed, for the first time, the detection of a human mAb up to 10 days after a 0.12 mg/kg administration to a horse. This development will expand the analytical capabilities of horse doping control laboratories towards protein-based biotherapeutics with adequate sensitivity, throughput, and cost-effectiveness.
Asunto(s)
Anticuerpos Monoclonales , Doping en los Deportes , Caballos , Animales , Humanos , Ratones , Cromatografía Líquida de Alta Presión/métodos , Doping en los Deportes/prevención & control , PéptidosRESUMEN
Nowadays, numerous websites attempt to commercialize over the internet various products, regardless of the lack of approval by the EMA or the FDA either for human or veterinary use. These products are often produced after aborted drug development due to insufficient or deleterious biological effects, synthesized based on natural products, or only based on scientific literature. However, the administration of such products is dangerous, considering the lack of official control over the production of these substances and the absence of approval by health authorities. In this short communication, we provide an extensive analysis of three misbranded and adulterated products sold over the internet named TB500, TB1000, and SGF1000. We confirm that the content of TB500/TB1000 products is not systematically consistent with it's former descriptions, but also that SGF1000 is mainly composed of sheep extracellular matrix (ECM) and blood proteins, and the signal corresponding to the purported growth promoters is excessively diluted.
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Aprobación de Drogas , Estados Unidos , Humanos , Animales , Ovinos , Preparaciones Farmacéuticas , United States Food and Drug AdministrationRESUMEN
In order to overcome the challenge associated with the screening of Anabolic-Androgenic Steroids abuses in animal competitions, a non-targeted liquid chromatography coupled to high resolution mass spectrometry based metabolomics approach was implemented on equine urine samples to highlight potential biomarkers associated with the administration of such compounds, using testosterone esters as model steroids. A statistical model relying on four potential biomarkers intensity could be defined to predict the status of the samples. With a routine application perspective, the monitoring of the highlighted potential biomarkers was first transferred into high-throughput liquid chromatography-selected reaction monitoring (LC-SRM). The model's performances and robustness of the approach were preserved and providing a first demonstration of metabolomics-based biomarkers integration within a targeted workflow using common benchtop MS instrumentation. In addition, with a view to the widespread implementation of such biomarker-based tools, we have transferred the method to a second laboratory with similar instrumentation. This proof of concept allows the development and application of biomarker-based strategies to meet current doping control needs.
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Doping en los Deportes , Testosterona , Animales , Biomarcadores/orina , Caballos , Laboratorios , Metabolómica/métodos , Esteroides/análisis , Congéneres de la TestosteronaRESUMEN
Ciclesonide (CIC) is the first inhaled highly potent corticosteroid that does not cause any cortisol suppression. It has been developed for the treatment of asthma in human and more recently in equine. CIC is the active compound of Aservo® EquiHaler® (Boehringer Ingelheim Vetmedica GmbH), the pre-filled inhaler generating a medicated mist based on Soft Mist™ technology. This prodrug is rapidly converted to desisobutyryl-ciclesonide (des-CIC), the main pharmacologically active compound. Due to its anti-inflammatory properties, CIC is prohibited for use in horse competitions. To set up an appropriate control, the determination of detection times and screening limits are required. Therefore, a highly sensitive analytical method based on supported liquid extraction (SLE) combined with liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) was developed to detect CIC and its active metabolite des-CIC in plasma. The lower limit of detection of CIC and des-CIC was approximately 1 pg/ml in plasma. After a pilot study conducted on a single horse at the recommended dose (eight actuations twice daily corresponding to 5.5 mg/day for the first 5 days, followed by 12 actuations once daily corresponding to 4.1 mg/day in the last 5 days), the same protocol was applied in the main study using six horses. In all horses, CIC and des-CIC levels were less than 5 and 10 pg/ml, respectively, at 36 h after the end of the administration. The outcome of this risk assessment study should be useful to draw any recommendations for horse competitions.
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Pregnenodionas , Profármacos , Animales , Cromatografía Liquida/métodos , Caballos , Proyectos Piloto , Pregnenodionas/análisisRESUMEN
Short half-life doping substances are, quickly eliminated and therefore difficult to control with traditional analytical chemistry methods. Indirect methods targeting biomarkers constitute an alternative to extend detection time frames in doping control analyses. Gene expression analysis (i.e., transcriptomics) has already shown interesting results in both humans and equines for erythropoietin (EPO), growth hormone (GH), and anabolic androgenic steroid (AAS) misuses. In humans, circulating cell-free microRNAs in plasma were described as new potential biomarkers for control of major doping agent (MDA) abuses. The development of a quantitative polymerase chain reaction (qPCR) method allowing the detection of circulating miRNAs was carried out on equine plasma collected on different type of tubes (EDTA, lithium-heparin [LiHep]). Although analyzing plasma collected in EDTA tubes is a standard method in molecular biology, analyzing plasma collected in LiHep tubes is challenging, as heparin is a reverse transcription (RT) and a PCR inhibitor. Different strategies were considered, and attention was paid on both miRNAs extraction quality and detection sensitivity. The detection of endogenous circulating miRNAs was performed and compared between the different types of tubes. In parallel, homologs of human miRNAs characterized as potential biomarkers of doping were sought in equine databases. The miRNA eca-miR-144, described as potential erythropoiesis stimulating agents (ESAs) administration candidate biomarker was retained and assessed in equine post-administration samples. The results about the qPCR method development and optimization are exposed as well as the equine miRNAs detection. To our knowledge, this work is the first study and the proof of concept of circulating miRNAs detection in plasma dedicated to equine doping control.
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Hematínicos , MicroARNs , Animales , Biomarcadores , Ácido Edético , Heparina , Caballos/genética , Reacción en Cadena de la Polimerasa , Reacción en Cadena en Tiempo Real de la Polimerasa/métodosRESUMEN
Synthetic androgenic anabolic steroids (AAS) are banned compounds and considered as major threats by both racing and sports international authorities. Hence, doping control laboratories are continually looking into analytical improvements to increase their detection capabilities, notably by means of emerging technologies. To enhance analytical performances for the detection of synthetic AAS such as stanozolol, specific chromatographic procedures have been developed using recent quaternary liquid chromatography technology originally designed for high-throughput standardized proteomics connected to mass spectrometry. Applying the newly designed elution procedures described in this paper to the analyses of stanozolol and its metabolites in complex matrixes revealed improved sensitivity compared to previously described high-throughput methods. Indeed, we report the consistent and reliable detection of 16ß-hydroxy-stanozolol down to 10 pg/mL in equine urine and being detectable up-to 3 months after a microdosing administration. Furthermore, a five months long elimination of stanozolol and its metabolites could be monitored on horse mane sections after a single dose administration. Our work highlights novel solutions to detect AAS with improved sensitivity. The application of such developments constitutes new landmarks for doping control laboratories and could be extended to other targeted compounds in residue analysis, toxicology, and metabolomics. Based on this work, the developed chromatographic method is now freely available within the Evosep Plus program.
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Anabolizantes , Doping en los Deportes , Animales , Caballos , Esteroides , Detección de Abuso de Sustancias , Espectrometría de Masas en Tándem , Congéneres de la TestosteronaRESUMEN
Clodronate is a non-nitrogen-containing bisphosphonate drug approved in equine veterinary medicine. Clodronate is prohibited for use in competition horses; therefore, to set up an appropriate control, detection times and screening limits are required. The quantitative method in plasma consisted of addition of chloromethylene diphosphonic acid as internal standard. Automated sample preparation comprised a solid phase extraction with weak anion exchange properties on microplate. After methylation of the residue with trimethyl orthoacetate, analysis was conducted by high-performance liquid chromatography-tandem mass spectrometry. Using a weighting factor of 1/(concentration)2 , good linearity was observed in the range of 1 to 500 ng/ml, with low limits of detection and quantification of 0.5 and 1 ng/ml, respectively. Precision and accuracy determined at four concentrations were satisfactory, with an error percentage less than 15%. Absence of carry-over and good stability of clodronic acid in plasma after a long-term storage at -20°C were verified. The method was successfully applied to the quantification of clodronic acid in plasma samples from horses administered with a single intramuscular administration of Osphos® at a mean dose of 1.43 ± 0.07 mg/kg. The observed detection time will be verified in a clinical population study conducted in diseased horses.
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Analgésicos no Narcóticos/sangre , Ácido Clodrónico/sangre , Caballos/sangre , Animales , Automatización , Cromatografía Líquida de Alta Presión , Doping en los Deportes , Inyecciones Intramusculares , Masculino , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Espectrometría de Masas en TándemRESUMEN
According to international sport institutions, the use of peroxisome proliferator activated receptor (PPAR)-δ agonists is forbidden at any time in athlete career due to their capabilities to increase physical and endurance performances. The (PPAR)-δ agonist GW501516 is prohibited for sale but is easily available on internet and can be used by cheaters. In the context of doping control, urine is the preferred matrix because of the non-invasive nature of sampling and providing broader exposure detection times to forbidden molecules but often not detected under its native form due to the organism's metabolism. Even if urinary metabolism of G501516 has been extensively studied in human subjects, knowledge on GW501516 metabolism in horses remains limited. To fight against doping practices in horses' races, GW501516 metabolism has to be studied in horse urine to identify and characterize the most relevant target metabolites to ensure an efficient doping control. In this article, in vitro and in vivo experiments have been conducted using horse S9 liver microsome fractions and horse oral administration route, respectively. These investigations determined that the detection of GW501516 must be performed in urine on its metabolites because the parent molecule was extremely metabolized. To maximize analytical method sensitivity, the extraction conditions have been optimized. In accordance with these results, a qualitative analytical method was validated to detect the abuse of GW501516 based on its most relevant metabolites in urine. This work enabled the Laboratoire des Courses Hippiques (LCH) to highlight two cases of illicit administration of this forbidden molecule in post-race samples.
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Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias/métodos , Tiazoles/análisis , Administración Oral , Animales , Femenino , Caballos , Masculino , Microsomas Hepáticos/metabolismo , PPAR delta/agonistas , Tiazoles/metabolismo , Tiazoles/orinaRESUMEN
With recent advances in analytical chemistry, liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS) has become an essential tool for metabolite discovery and detection. Even if most of the common drug transformations have already been extensively described, manual search of drug metabolites in LC-HRMS/MS datasets is still a common practice in toxicology laboratories, complicating metabolite discovery. Furthermore, the availability of free open-source software for metabolite discovery is still limited. In this article, we present MetIDfyR, an open-source and cross-platform R package for in silico drug phase I/II biotransformation prediction and mass-spectrometric data mining. MetIDfyR has proven its efficacy for advanced metabolite identification in semi-complex and complex mixtures in in vitro or in vivo drug studies and is freely available at github.com/agnesblch/MetIDfyR.
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Preparaciones Farmacéuticas/análisis , Bibliotecas de Moléculas Pequeñas/análisis , Quimioinformática , Cromatografía Liquida , Estructura Molecular , Preparaciones Farmacéuticas/metabolismo , Bibliotecas de Moléculas Pequeñas/metabolismo , Espectrometría de Masas en TándemRESUMEN
Bisphosphonates are prohibited drugs according to Article 6 of the International Agreement on Breeding, Racing and Wagering of the International Federation of Horseracing Authorities (IFHA) and the International Equestrian Federation (FEI). These compounds are used for the treatment of lameness, navicular and bone diseases in horses and are divided into two groups: non-nitrogen-containing bisphosphonate drugs (e.g. clodronic acid) and nitrogen-containing bisphosphonate drugs (e.g. zoledronic acid). Their hydrophilic properties and the high affinity for the bone matrix make the control of their use quite difficult. Current analytical strategies to detect such compounds often rely on a solid phase extraction (SPE) followed by detection by means of UHPLC-MS/MS after methylation with chemical reagents. To improve the analysis throughput and to eliminate the need for chemical derivatization, an innovative 96-well SPE followed by ion chromatography-mass spectrometry was developed. Analyses are conducted on an ICS-6000 HPIC system coupled to a TSQ Altis™ (Thermo Scientific™). The use of a 96-well SPE allowed 5-fold sample increase and a 6-fold throughput improvement. While preliminary results conducted on horse plasma exhibited similar performances to the method for the detection of non-nitrogen-containing bisphosphonates, the analytical performances of nitrogen-containing bisphosphonates were greatly improved.
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Conservadores de la Densidad Ósea/sangre , Difosfonatos/sangre , Caballos/sangre , Animales , Cromatografía Líquida de Alta Presión , Doping en los Deportes , Extracción en Fase Sólida , Espectrometría de Masas en TándemRESUMEN
Recombinant human erythropoietin (rHuEPO) belongs to the therapeutic class of erythropoiesis stimulating agents (ESAs) due to its implication in the creation pathway of red blood cells and thus enhancement of oxygenation. Because of this bioactivity, rHuEPO has been considered as a major doping agent in sports competitions for decades. Over the years, doping control laboratories designed several analytical strategies applied to human and animal samples to highlight any misuse. Even though multiple analytical approaches have been reported, none has yet been dedicated to racing camels. Here, we describe an analytical strategy to test camel plasma samples at screening using an ELISA assay and a targeted nano-liquid chromatography-high-resolution tandem mass spectrometry for confirmatory analysis. The method was validated and has been successfully applied to post-race samples, allowing the detection of a positive case of rHuEPO administration.
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Camelus/metabolismo , Doping en los Deportes/métodos , Eritropoyetina/análisis , Detección de Abuso de Sustancias/métodos , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Eritropoyetina/química , Humanos , Espectrometría de Masas , Proteínas Recombinantes/análisis , Reproducibilidad de los Resultados , DeportesRESUMEN
There is an urgent need to implement holistic and untargeted doping control protocols with improved discriminatory power, compared to conventional methods that only target doping agents. Metabolomics, which aims to characterize all metabolites present in biological matrices, could fulfill this need. In this context, the aim of this study was to evaluate the impact of environmental factors on the ability to obtain a metabolic signature of stanozolol administration in horse doping situation. Urine samples from 16 horses breeded in two different places were collected over a one-year period, before, during and seven months after the administration of stanozolol, a horse doping agent. Metabolomic analysis was performed using ultra-high pressure reverse phase liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (MS). Results showed a major impact of the nutritional regimen, drug administration (for de-worming purpose) and breeding place on the metabolite profiles of horse urines, which hampered the detection of metabolic perturbations induced by stanozolol administration. After having used MS/MS experiments to characterize some MS features related to these environmental factors, we showed that highlighting and then removing the features impacted by these confounding factors before performing supervised multivariate statistical analyses could address this issue. In conclusion, adequate consideration should be given to environmental and physiological factors; otherwise, they can emerge as confounding factors and conceal doping administration.
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Cromatografía de Fase Inversa/métodos , Doping en los Deportes/métodos , Caballos/orina , Espectrometría de Masas/métodos , Metabolómica/métodos , Prednisolona/orina , Detección de Abuso de Sustancias/métodos , Animales , Cromatografía de Fase Inversa/veterinaria , Límite de Detección , Espectrometría de Masas/veterinaria , Detección de Abuso de Sustancias/veterinariaRESUMEN
Cobra (Naja naja kaouthia) venom contains a toxin called α-cobratoxin (α-Cbtx) containing 71 amino acids (MW 7821 Da) with a reported analgesic power greater than morphine. In 2013, the first analytical method for the detection of α-Cbtx in equine plasma was developed by Bailly-Chouriberry et al, allowing the confirmation of the presence of α-Cbtx at low concentrations (1-5 ng/mL or 130-640 fmol/mL) in plasma samples. To increase the method sensitivity and therefore to improve the detection of α-Cbtx in post-administration plasma samples, a nano-liquid chromatography-mass spectrometry/high resolution mass spectrometry (nLC-MS/HRMS) method was developed. This new method allowed us to confirm the presence of α-Cbtx in plasma samples spiked at 100 pg/mL (12.8 fmol/mL) and the detection of α-Cbtx was obtained in plasma samples collected 72 hours post-administration (50 pg/mL or 6.4 fmol/mL) which was defined as the limit of detection (LOD). The presented method is 20-fold more sensitive compared to the method previously described.
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Analgésicos/sangre , Proteínas Neurotóxicas de Elápidos/sangre , Caballos/sangre , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Cromatografía Liquida/métodos , Doping en los Deportes , Límite de DetecciónRESUMEN
Erythropoiesis Stimulating Agents (ESAs) were developed for therapeutic purposes to stimulate red blood cell (RBC) production. Consequently, tissue oxygenation is enhanced as athlete's endurance and ESAs misuse now benefits doping. Our hypothesis is that most of ESAs should have similar mechanisms and thus have the same effects on metabolism. Studying the metabolome variations could allow suspecting the use of any ESAs with a single method by targeting their effects. In this objective, a metabolomic study was carried out on 3 thoroughbred horses with a single administration of 4.2µg/kg of Mircera®, also called Continuous Erythropoiesis Receptor Activator (CERA). Blood and urine samples were collected from D-17 to D+74 and haematological parameters were followed throughout the study as plasmatic CERA concentration (ELISA). Urine and plasma metabolic fingerprints were recorded by Liquid Chromatography coupled to High Resolution Mass Spectrometry (LC-HRMS) in positive and negative mode. After preprocessing steps, normalized data were analyzed by multivariate statistics to build OPLS models. Hemoglobin concentration and hematocrit showed a significant increase after CERA administration unlike reticulocytes. CERA concentration showed a high intensity peak and then a slow decrease until becoming undetectable after D+31. Models built with multivariate statistics allow a discrimination between pre and post-administration plasma and urine samples until 74days after administration, i.e. 43days longer than ELISA method. By reducing and studying variables (ions), some potential candidate biomarkers were found.
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Cromatografía Liquida , Doping en los Deportes/métodos , Eritropoyesis/efectos de los fármacos , Eritropoyetina/farmacología , Caballos , Espectrometría de Masas , Metaboloma/efectos de los fármacos , Polietilenglicoles/farmacología , Animales , Eritropoyetina/sangre , Eritropoyetina/orina , Hematínicos/sangre , Hematínicos/farmacología , Hematínicos/orina , MetabolómicaRESUMEN
The improvement of doping control is an ongoing race. Techniques to fight doping are usually based on the direct detection of drugs or their metabolites by analytical methods such as chromatography hyphenated to mass spectrometry after ad hoc sample preparation. Nowadays, omic methods constitute an attractive development and advances have been achieved particularly by application of molecular biology tools for detection of anabolic androgenic steroids (AAS), erythropoiesis-stimulating agent (ESA), or to control human growth hormone misuses. These interesting results across different animal species have suggested that modification of gene expression offers promising new methods of improving the window of detection of banned substances by targeting their effects on blood cell gene expression. In this context, the present study describes the possibility of using a modified version of the dedicated Human IVD (in vitro Diagnostics) PAXgene® Blood RNA Kit for horse gene expression analysis in blood collected on PAXgene® tubes applied to the horse biological passport. The commercial kit was only approved for human blood samples and has required an optimization of specific technical requirements for equine blood samples. Improvements and recommendations were achieved for sample collection, storage and RNA extraction procedure. Following these developments, RNA yield and quality were demonstrated to be suitable for downstream gene expression analysis by qPCR techniques. Copyright © 2017 John Wiley & Sons, Ltd.
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Perfilación de la Expresión Génica , ARN , Animales , Doping en los Deportes , Caballos , Humanos , ARN/química , Manejo de EspecímenesRESUMEN
Since the availability on the European market of the vaccine Improvac® dedicated to male pig immunological castration, the risk of misuse of this product in horses is now considered as a threat for the horseracing industry. Immunological castration is not allowed by the racing codes (immune system, Article 6). Indeed, this vaccination against the hypothalamic hormone luteinizing hormone-releasing hormone or gonadotropin-releasing hormone (GnRH) will prevent the release from the anterior pituitary of luteinizing hormone and follicle stimulating hormone, which are required for the development and activity of gonads in males (testes) and female (ovaries) and therefore all their subsequent physiological functions. This treatment will induce a strong hormonal variation resulting in a behaviour modification of the animals. In this work, four male standardbreds treated with Improvac® vaccine (two intramuscular injections within 4 weeks) were studied. Monitoring of the total scrotal width showed a decrease of the scrotum size (37%) and production of anti-GnRH antibodies was detected up to 200 days after the first injection. Anti-GnRH antibodies were detected in plasma after caprylic acid precipitation followed by an enzyme-linked immunosorbent assay (ELISA) as a rapid and efficient screening method applicable to routine analysis. These results were correlated to a switch of the sexual status from male group to gelding/female group obtained by a steroidomic approach with urine based on ten endogenous compounds. Copyright © 2017 John Wiley & Sons, Ltd.
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Ensayo de Inmunoadsorción Enzimática/métodos , Hormona Folículo Estimulante/química , Hormona Liberadora de Gonadotropina/química , Hormona Luteinizante/química , Animales , Castración , Femenino , Hormona Folículo Estimulante/metabolismo , Caballos , Hormona Luteinizante/metabolismo , Masculino , Porcinos , VacunaciónRESUMEN
Cobalt is an essential mineral micronutrient and is regularly present in equine nutritional and feed supplements. Therefore, cobalt is naturally present at low concentrations in biological samples. The administration of cobalt chloride is considered to be blood doping and is thus prohibited. To control the misuse of cobalt, it was mandatory to establish an international threshold for cobalt in plasma and/or in urine. To achieve this goal, an international collaboration, consisting of an interlaboratory comparison between 5 laboratories for the urine study and 8 laboratories for the plasma study, has been undertaken. Quantification of cobalt in the biological samples was performed by inductively coupled plasma-mass spectrometry (ICP-MS). Ring tests were based on the analysis of 5 urine samples supplemented at concentrations ranging from 5 up to 500 ng/mL and 5 plasma samples spiked at concentrations ranging from 0.5 up to 25 ng/mL. The results obtained from the different laboratories were collected, compiled, and compared to assess the reproducibility and robustness of cobalt quantification measurements. The statistical approach for the ring test for total cobalt in urine was based on the determination of percentage deviations from the calculated means, while robust statistics based on the calculated median were applied to the ring test for total cobalt in plasma. The inter-laboratory comparisons in urine and in plasma were successful so that 97.6% of the urine samples and 97.5% of the plasma samples gave satisfactory results. Threshold values for cobalt in plasma and urine were established from data only obtained by laboratories involved in the ring test. Copyright © 2017 John Wiley & Sons, Ltd.