Anabolic l'indienne

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Anabolic l'indienne
January 2005 Analytica Chimica Acta 529(1-2):311-316
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New illegal veterinary drugs are produced and distributed on the black market continuously. The anabolic drugs described here were found on the black market for body-builders, but are probably also available for growth promoting purposes in cattle.The residue laboratories are obligated to develop extraction and detection methods to identify and/or quantify the metabolites of these continuously emerging new drugs. In practice, the formation of the metabolites is investigated with animal experiments in which vertebrate animals are treated with the illegal compound. Different matrices of the animal are collected and examined. Because of the complexity and duration of the animal experiment and the method development, a lot of time and money is consumed. Some of these vertebrate experiments can be replaced by invertebrate metabolism experiments [K. De Wasch, S. Poelmans, T. Verslycke, C. Janssen, N. Van Hoof, H. De Brabander, Anal. Chem. Acta 473 (2002) 59; T. Verslycke, K. De Wasch, H. De Brabander, C. Janssen, Gen. Comp. Endocr. 126 (2002) 190; S. Poelmans, K. De Wasch, Y. Martelé, R. Schilt, N. Van Hoof, H. Noppe, T. Verslycke, C.R. Janssen, D. Courtheyn, H.F. De Brabander, Proceedings of the Euro Food Chem XII Strategies for Safe Food, September 24–26, Brugge, Belgium, 2003, p. 74]. By using an invertebrate for the metabolism studies there is a reduction in time and money in comparison with vertebrate animal experiments.In this study an invertebrate model, the mysid crustacean Neomysis integer (Crustacea, Mysidacea) was used as an alternative model for metabolism of some new anabolic drugs.The investigated analytes were dehydroepiandrosterone (DHEA, (3β)-3-hydroxy-androst-5en-17one), maxterone (ADL: 5α-androstan-3β,17β-diol), 5-androstenedione (5AED, 5-androstene-3,17-dione), 5α-androstenedione (5αAED, 1-androstene-3,17-dione) and 1-testosterone (A1T, 1-(5α)T, 1-(5α)-androsten-17β-ol-3-one).
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... Finally, this species has been cultured in our laboratory for a long time and recently it has been used extensively as a model for endocrine disruption research (Heijerick, 1994; Poelmans et al. 2005; 2003a,b,c;2004c). Most of the recent studies on endocrine disruption using N. integer are an integral part of the doctoral dissertation of Tim Verslycke, published in 2003, which focuses on the energy and steroid metabolism of this species. ...
... Finally, this species has been cultured in our laboratory for a long time and recently it has been used extensively as a model for endocrine disruption research (Heijerick, 1994; Poelmans et al. 2005; 2003a,b,c;2004c). Most of the recent studies on endocrine disruption using N. integer are an integral part of the doctoral dissertation of Tim Verslycke, published in 2003, which focuses on the energy and steroid metabolism of this species. ...
... Often not the parent (original) substances have to be detected but also one or more metabolites, depending upon the matrix analysed. Animal experiments are needed for those purposes but also some alternatives have been described [6, 7] . ...
A residue is a trace (microg kg(-1), ng kg(-1)) of a substance, present in a matrix. Residue analysis is a relatively young discipline and a very broad area, including banned (A) substances as well as registered veterinary medicinal products (B substances). The objective of this manuscript is to review future trends in the analysis of residues of veterinary drugs in meat producing animals out of historical perspectives. The analysis of residues in meat producing animals has known a tremendous evolution during the past 35-40 years. In the future, it can be foreseen that this evolution will proceed in the direction of the use of more and more sophisticated and expensive machines. These apparatus, and the necessary human resources for their use, will only be affordable for laboratories with sufficient financial resources and having guarantee for a sufficient throughput of samples.
De laatste jaren is er een toenemende maatschappelijke bezorgdheid en wetenschappelijke discussie ontstaan rond de verspreiding en de mogelijke effecten van stoffen met een vermoedelijke of bekende hormoonverstorende werking. Het huidige doctoraatsonderzoek kadert binnen deze problematiek en beschrijft de ontwikkeling en validatie van meetmethoden voor de detectie van oestrogenen en chlorotriazine pesticiden in verschillende milieumatrices zoals water, sediment, materie in suspensie en aquatische organismen. Meer specifiek wordt de methodiek voor de detectie van lage ng.l-1 of ng.g-1 concentraties van deze hormoonverstorende stoffen (HVS) in verschillende complexe matrices beschreven. Verder ook wordt er ook een overzicht gegeven van het voorkomen van deze stoffen in een estuarien ecosysteem zoals het Schelde estuarium (België-Nederland). In hoofdstuk I wordt een inleiding gegeven tot de problematiek van hormoonverstoring en de recente ontwikkelingen in de milieuchemie. Dit doctoraatsonderzoek werd uitgevoerd binnen een interdisciplinair onderzoeksproject, Endis-Risks. Dit 4-jarig project had tot doel het bestuderen van het voorkomen van, de blootstelling aan en de mogelijke effecten van HVS in het Schelde estuarium. In dit onderzoekswerk wordt de nadruk gelegd op 2 groepen van HVS, namelijk de oestrogenen en de chlorotriazine pesticiden. Om een idee te krijgen van de mogelijke risico’s verbonden aan de aanwezigheid van deze stoffen in het milieu wordt een overzicht gegeven van hun chemische eigenschappen, hun gebruik, hun voorkomen in het milieu en de wetgeving hieromtrent en/of omtrent het misbruik in de vetmesterij. Als laatste in dit hoofdstuk wordt de risicoschatting procedure behandeld. In hoofdstuk II.1. wordt de ontwikkeling en de validatieprocedure beschreven van een GC-EI-MS-MS methode die de routine analyse van 4 oestrogenen (E1, E2, E3 en EE2) in milieuwaterstalen in het lage ng.l-1 gebied toelaat. Deze methode omvat extractie met behulp van speedisk extractie en detectie met gaschromatografie gekoppeld aan massaspectrometrie in electron impact mode (GC-EI-MS-MS). Daarnaast worden de eigenschappen van de methode zoals terugvinding, specificiteit, precisie, kalibratie, detectielimieten en stabiliteit van de componenten beschreven voor elk van de oestrogenen die onderzocht werden. Toepassing van deze Belac geaccrediteerde methode voor de analyse van waterstalen van het Schelde estuarium toonde aan dat oestrone (E1), het afbraakprodukt van oestradiol (E2), het belangrijkste natuurlijke oestrogeen, het meest frequent en in de hoogste concentraties werd gevonden. In hoofdstuk II.2. worden de resultaten van 4 jaar (2002-2005) onderzoek betreffende het voorkomen van oestrogenen in het Schelde estuarium (België-Nederland) beschreven. Extractie van de waterstalen werd uitgevoerd met behulp van speedisk extractie zoals beschreven in hoofdstuk II.1.. Materie in suspensie, sediment en biota stalen werden geëxtraheerd met behulp van Accelerated Solvent Extraction (ASE). Extracten werden verder geanalyseerd met behulp van GC-EI-MS-MS. In alle matrices die in beschouwing werden genomen, nl. water, materie in suspensie, sediment en biota werden oestrone (E1) en oestradiol (E2) gevonden, waarbij E1 het vaakst en in de hoogste concentraties. Concentraties van oestriol (E3), het afbraakproduct van E1 en ethinylestradiol (EE2), het meest prominente oestrogeen in contraceptiva, waren lager dan de detectielimiet. Deze studie toonde aan dat de oestrogeen concentraties in het Schelde estuarium van dezelfde grootte-orde zijn als deze die beschreven zijn voor (zoetwater) oppervlaktewater en afvalwaters. In hoofdstuk II.3. wordt een case-study beschreven betreffende de detectie van oestrogenen in een ongekend waterstaal, verdacht voor het bevatten van groeipromotoren. Hiervoor werden verschillende analytische methoden aangewend. Ten eerste werden in vivo muistesten uitgevoerd waarbij dit ongekend waterstaal werd toegediend aan muizen via drinkwater en onderhuids inspuiten. Daarnaast werd er een in vitro screening uitgevoerd met de Yeast Estrogenic Screen (YES)-test. Na extractie van het staal door middel van speedisk extractie (gebaseerd op de methode beschreven in hoofdstuk II.1.) en HPLC-fractionatie werden de stalen geanalyseerd met behulp van gaschromatografie en vloeistofchromatografie gekoppeld aan massaspectrometrie (GC- en LC-MS-MS). In dit waterstaal werden uiteindelijk ng.l-1 concentraties gedetecteerd van E1 en EE2. Hoofdstuk II.4. beschrijft de ontwikkeling van een routine methode voor de detectie van ng.l-1 niveaus van EGAs (oestrogenen, gestagenen en androgenen) en corticosteroïden in waterige stalen (zoals vb. drinkwater en/of supplementen) die op de zwarte markt verkocht worden. Hiervoor werden stalen geëxtraheerd met behulp van speedisk extractie en gefractioneerd met behulp van HPLC-fractionatie (cfr. Hoofdstukken II.1. en II.3.). Screening voor EGAs werd uitgevoerd met GC-EI-MS-MS en voor corticosteroïden met behulp van gaschromatografie gekoppeld aan massaspectrometrie in de negatieve chemische ionisatie mode (GC-NCI-MS). Voor de corticosteroïden werd, indien het staal verdacht was voor dexamethasone (Dxm) of betamethasone (Btm), vloeistofstofchromatografie gekoppeld aan massaspectrometrie (LC-ESI-MS-MS) ingezet ter bevestiging. Dit onderzoek toonde aan dat de combinatie van GC- en LC-MS-MS de detectie van steroïdhormonen in lage ng.l-1 concentraties in ongekende waterige stalen mogelijk maakt. In dit hoofdstuk worden 2 case-studies beschreven waarbij medroxyprogesterone acetaat (MPA) en Btm werden teruggevonden in verdachte waterstalen aan lage ng.l-1 concentraties. In hoofdstuk III wordt het voorkomen van de chlorotriazine herbiciden atrazine, simazine en terbutylazine in de verschillende matrices van het Schelde estuarium beschreven over een periode van 4 jaar (2002-2005). Deze studie toonde aan dat, in de waterstalen, atrazine het vaakst en in de hoogste concentraties werd gevonden, gevolgd door simazine en terbutylazine. Ook in de materie in suspensie werden atrazine en simazine aan lage ng.g-1 concentraties gedetecteerd. Sporen van deze herbiciden werden teruggevonden in sedimenten, doch aan niveaus beneden de detectielimiet. Als laatste werd de toxiciteit van atrazine voor Neomysis integer, een mysidsoort in het Schelde estuarium, bestudeerd. Hiervoor werden N. integer juvenielen (< 24 u oud) blootgesteld aan verschillende atrazine concentraties om de acute (mortaliteit) en chronische effecten op vervelling en groei te evalueren. Deze studie toonde aan dat atrazine toxisch kan zijn voor deze mysids doch dat bij blootstelling aan concentraties die gemeten werden in het Schelde estuarium mogelijks geen mortaliteit en effecten op de groei optreden. In hoofdstuk V worden de algemene conclusies en toekomstperspectieven van dit doctoraatsonderzoek geformuleerd. Samenvattend kan gesteld worden dat het hoofddoel van dit onderzoek de detectie van HVS was, in het lage ng.l-1 of ng.g-1 concentratiegebied en in verschillende complexe matrices.
Drostanolone is one of the most frequently detected anabolic androgenic steroids in doping control analysis. Here, we studied drostanolone urinary metabolic profiles using liquid chromatography quadruple time of flight mass spectrometry (LC-QTOF-MS) in full scan and targeted MS/MS modes with accurate mass measurement. The drug was administered to one healthy male volunteer and liquid-liquid extraction along with direct-injection were used to analyze urine samples. Chromatographic peaks for potential metabolites were identified with the theoretical [M-H]- as a target ion in a full scan experiment and actual deprotonated ions were analyzed in targeted MS/MS mode. Eleven metabolites including five new sulfates, five glucuronide conjugates, and one free metabolite were confirmed for drostanolone. Due to the absence of useful fragment ions to illustrate the steroid ring structure of drostanolone phase II metabolites, gas chromatography mass spectrometry (GC-MS) was used to obtain structural details of the trimethylsilylated phase I metabolite released after enzymatic hydrolysis and a potential structure was proposed using a combined MS approach. Metabolite detection times were recorded and S4 (2α-methyl-5α-androstan-17-one-6β-ol-3α-sulfate) and G1 (2α-methyl- -5α-androstan-17-one-3α-glucuronide) were thought to be new potential biomarkers for drostanolone misuse which can be detected up to 24 days by liquid-liquid extraction and 7 days by direct-injection analysis after intramuscular injection. S4 and G1 were also detected in two drostanolone-positive routine urine samples.
Current evidence suggests that neo formation of the anabolic steroid boldenone (androsta-1,4-diene-17-ol-3-one) occurs in calves' faecal material, making it difficult to distinguish between illegally administered boldenone and its potential endogenous presence. This strengthens the urgent need to elucidate the pathway leading to boldenone formation. In our laboratory, the invertebrate Neomysis integer (Crustacea, Mysidacea) was used since 2004 as an alternative model for the partial replacement of vertebrate animals in metabolisation studies with illegal growth promotors and veterinary drugs, e.g. boldenone. The present study evaluates the metabolic capacity of other invertebrates, the brine shrimp Artemia franciscana and maggots of the greenbottle fly Lucilia sericata. The first results indicate that maggots of L. sericata are able to convert phytosterols and -stanols, nowadays in substantial amounts added to animal feed, into androsta-1,4-diene-3,17-dione (ADD), the precursor of boldenone, at a yield of 0.10-0.14% (p<0.001, significance compared to endogenous excretion of maggots) but not to boldenone itself. Furthermore, beta-testosterone, an endogenous hormone, was transformed into androst-4-ene-3,17-dione (AED), ADD and beta-boldenone at a significant (p<0.001, significance compared to endogenous excretion of maggots) yield of circa 13%, 0.80% and 2.2%, respectively. In future studies these results are of value to further evaluate the use of maggots of L. sericata as an invertebrate model in metabolisation studies.
Current evidence suggests that the biocide tributyltin (TBT) causes the development of imposex, a state of pseudohermaphrodism in which females exhibit functional secondary male characteristics, by altering the biotransformation or elimination of testosterone. Imposex in gastropods following TBT exposure is the most complete example of the effects of an endocrine disrupter on marine invertebrates. Previous studies have demonstrated that the estuarine mysid Neomysis integer converts testosterone into multiple polar and nonpolar metabolites resulting from both phase I and phase II biotransformations. In this study, the effects of TBT chloride (TBTCl) on the phase I and II testosterone metabolism of N. integer were evaluated. The TBTCl was highly toxic to N. integer (96-h median lethal concentration [LC50] of 164 ng/L). To assess the effects on testosterone metabolism, mysids were exposed for 96 h to different concentrations of TBTCl (control, 10, 100, and 1,000 ng/L), and testosterone elimination as polar hydroxylated, nonpolar oxido-reduced, and glucose- and sulfate-conjugated metabolites was examined. The TBTCl differentially affected testosterone metabolism. The effect of TBTCl on phase I metabolism was unclear and has been shown to vary among species, likely depending on the inducibility or presence of certain P450 isozyme families. Reductase activity and metabolic androgenization were induced in the 10-ng/L treatment, whereas higher concentrations resulted in a reduction of sulfate conjugation. The exact mechanisms underlying TBT-induced imposex and alterations in the steroid metabolism need to be further elucidated.
The review summarizes current knowledge on the possible illegal use of the anabolic steroid boldenone. The presence of' boldenone and metabolites in different animal species and the possibility of the occurrence of endogenous boldenone and metabolites is assessed, as are the methods of analysis used for detection. Different laboratories in the European Union have examined the occurrence of boldenone and its metabolites. The results were discussed at different meetings of a European Commission DG-SANCO Working Party) and summarized in an expert report. The situation of the different laboratories at this time is also covered herein. The overall conclusion of the Working Party was that there was a necessity for further research to distinguish between naturally occurring and illegally used boldenone forms. The confirmation of the presence of boldenone metabolites (free and conjugated forms) in certain matrices of animals is proposed as a marker for the illegal treatment with boldenone.
Phase I and phase II chemical detoxication processes were elucidated in Daphnia magna using in vivo techniques and [14C]testosterone as a substrate. Testosterone was used because this compound undergoes multiple biotransformations and its metabolites are well characterized in other species. In addition, regulation of these processes by the endogenous steroid hormone, 20-hydroxyecdysone, was investigated. Daphnids produced at least ten polar phase I metabolites and four nonpolar phase I metabolites of testosterone. Six of the ten polar metabolites have been identified as monohydroxy-products of testosterone. The polar metabolites were preferentially excreted while the nonpolar metabolites were preferentially retained by the daphnids. In addition, testosterone and all phase I metabolites were also excreted as glucose conjugates. A polar metabolite designated ‘C’ was preferentially conjugated with glucose over the other metabolites. Testosterone and its polar phase I metabolites were also excreted as sulfate conjugates with 2α-hydroxytestosterone being the predominant sulfate-conjugated metabolite. In contrast to glucose conjugation, no nonpolar phase I metabolites of testosterone were sulfate conjugated. Twenty-four hour pre-exposure of daphnids to 4.2 μM 20-hydroxyecdysone did not affect phase I metabolism of testosterone, but differentially modulated phase II conjugation in a manner suggesting the presence of at least two glucosyltransferases and two sulfotransferases. Treatment with 20-hydroxyecdysone significantly increased the elimination of sulfate conjugates due largely to increased sulfate conjugation of unmetabolized testosterone. These results demonstrate that daphnids can convert polycyclic compounds to multiple polar and nonpolar metabolites resulting from both phase I and phase II biotransformations, and that some phase II activities are under the regulatory control of 20-hydroxyecdysone.
The continuous production of new illegal veterinary drugs and related products requires residue laboratories to initiate research into developing fast and accurate extraction and detection methods for the identification (and/or quantification) of the major analyte or metabolites of these compounds. In practice, animal experiments are carried out in which vertebrate animals (bovine, porcine, …) are treated orally or intramuscularly with the illegal compound. Different matrices (urine, faeces, blood) are collected over 2 or 3 weeks until the animal is sacrificed. Edible matrices (meat, liver, kidney,…) are collected. Because of the complexity of the animal experiment and the method development, a lot of valuable time and money is consumed.Recent studies have shown that some of these vertebrate experiments can be replaced by invertebrates metabolism studies. Vertebrate-type steroids such as testosterone have been used as substrates t
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Teen se masturbe avec une bouteille
Ils l'ont mis dans la voiture et lui ont baisé le cul