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  • Detection of sulfo-conjugated anabolic steroids metabolites in antidoping initital and confirmatory analysis

    Detection of sulfo-conjugated anabolic steroids metabolites in antidoping initital and confirmatory analysis

    By

    Investigateur principal
    C. Georgakopoulos
    Chercheur
    E. Lyris

    Doping Control Laboratory of Athens

    Grèce   ―   2011   ―   Complété

    Sommaire

    Code: 11A13CG

    Anabolic androgenic steroids (AAS) are the most frequent abused substances in sports and are included in the World Antidoping Agency (WADA) List of prohibited substances. AAS are extensively metabolized in the liver and their target tissues. The metabolic pathways are divided into phase-I and phase-II reactions. Phase-I reactions involve oxidation, hydrolysis and reduction, which introduce new functional groups for the subsequent phase-II reactions (i.e. conjugation).

    For the endogenous androgens and for exogenous AAS the main phase-II reactions are conjugation with glucuronic acid (glucuronidation) or with a sulfo-moiety (sulphatation). The screening methods used by the Antidoping Laboratories usually focus on those metabolites, that are excreted unconjugated or as glucuronides into the urine. Extraction of the gluco- deconjugated steroids from the matrix and concentration of the analytes is performed by liquid-liquid extraction (with diethylether or tertbutylmethylether) or solid phase extraction followed by mass spectrometric detection either by liquid chromatography mass spectrometry or gas chromatography mass spectrometry. By using this initial screening extraction protocol the Antidoping Laboratories substantially ignore the sulfo-conjugated part of AAS. Nevertheless there are AAS for which the longer detected metabolite is a sulfo-conjugate. Sulfo-conjugated AAS are relatively easy to be detected directly since the development of instrumentation providing interfacing of liquid chromatographic (LC) separation to mass spectrometric (MS) detection, especially via electrospray ionisation (ESI), has opened up broad possibilities for the direct analysis of sulfo-conjugated substances. Moreover, sulfo-conjugated substances can be extracted from urine using ethyl acetate, instead of diethylether, as extraction solvent. The objectives of this project will be:

    a) To develop a screening method for the already known sulfo-conjugated metabolites of AAS, and

    b) To investigate the existence of not yet reported sulfo-conjugated metabolites of AAS, that can improve detectability and identification in either initial screening protocol or confirmation methods.

    Main Findings

    Anabolic steroids such as oxandrolone, madol, formebolone, methenolone, 17- methylnandrolone and mesterolone were tested for the existence of sulfo-conjugated metabolites. Metabolic samples from long-term excretion studies were tested for any sulphate metabolite and where any sulphate metabolite was found, an evaluation of its retrospectivity was performed in comparison with their free and gluco-conugated metabolites used for their monitoring in GC/HRMS analysis. In most cases where new metabolites were found, a detailed characterization of their structures based on mass spectrometry techniques was also performed. Additionally, spotted metabolic samples for oxymetholone, drostanolone, norethandrolone, danazol, clostebol, methandriol, calusterone, furazabol, fluoxymesterone, oxymesterone, boldenone, mesterolone, methandienone, methyltestosterone, oral turinabol, methenolone, and tibolone that include the known, up to that time, anabolic steroids with sulphates metabolites, as well as other AASs with unknown sulphate metabolism were tested in order to develop a new screening method for sulphate metabolites. Samples from the above listed steroids were extracted and analyzed using a screening method based on alkaline extraction with ethylacetate and LC/QTOF analysis in a negative mode. Potential sulfate metabolites of these steroids were drawn and the molecular ions were calculated and extracted using the instrument software.

    Conclusions

    The investigation of sulfo-conjugated metabolites of methenolone and mesterolone led to the discovery of new metabolites of at least equal or better retrospectivity compared to the already known gluco-conjugated metabolites detected by GCMS. Furthermore, a sulfo-conjugated long-term metabolite of 17-methylnandrolone was discovered (unpublished results). The analysis of madol, formebolone and oxandrolone didn’t lead to any new (sulfo-) metabolite, at least to a concentration level that would be detectable by the technology used in this study. A screening method for sulfo-conjugated metabolites was developed for several anabolic steroids based on literature data, using accurate mass measurements for the extracted ion chromatograms and leading to a number of new sulfo-conjugated metabolites. Their structures, as well as their retrospectivity for the monitoring of their parent compounds abuse for doping control purposes were not evaluated in the framework of this project.

    Voir le projet à propos de Detection of sulfo-conjugated anabolic steroids metabolites in antidoping initital and confirmatory analysis
  • Determination of red blood cell deformability in athletes during the course of the year: Considering gender, ethinic and traning conditions

    Determination of red blood cell deformability in athletes during the course of the year: Considering gender, ethinic and traning conditions

    By

    Investigateur principal
    M. Grau

    German Sport University

    Allemagne   ―   2011   ―   Complété

    Sommaire

    Code: 11D13MG

    Performance-enhancing aids are not new to athletes. Owing to fame, honor and economic benefits arising from success in competitions, there is rather a long history of cheating in sports.  After the usage of erythropoietin could effectively been proven, lots of athletes turned to an older doping procedure: autologous blood doping to increase the number of circulating red blood cells (RBCs). This increases the oxygen delivery through the blood to the working muscle which profoundly enhances an athletes´ performance. The International Olympic Committee (IOC) forbade blood boosting after the 1984 Olympics, despite the fact that no methods had been devised for unequivocal detection. Valid and established methods for the detection of autologous blood doping are still missing but our recent findings indicate that the RBC flexibility represents a useful marker to detect blood doping. The deformability is an essential feature enabling RBCs to access and transit the capillary bed and to deliver oxygen to the muscle cells due to the fact that the vessel diameter of the capillary is smaller than the resting cell diameter. 
    The aim of the presented study is the investigation of RBCs flexibility in male and female endurance athletes and male and female non-athletes during a one-year period. Thereby, a variety of parameters, known to influence RBC deformability like L-arginine and NO levels, are planned to be investigated. Also, the influence of the female hormone cycle on the RBC deformability should be investigated. Furthermore, the influence of competition and training periods and the influence of the ethnic background on RBCs flexibility will be evaluated. The findings obtained with this study will serve as a basis for further investigations and the development of a routinely applicable detection method to detect autologous blood doping.

    Main Findings:

    Autologous blood doping is the practice of boosting the number of red blood cells (RBC) in order to improve aerobic capacity and thus athletic performance and endurance. RBC deformability, the ability of RBC to change their shape under a given level of applied shear stress, is an important cell property to ensure oxygen and nutrient supply to the working tissue in the microcirculation. Thus, RBC deformability may also determine performance capacity. Hypothermic blood storage decreases RBC deformability, thus, monitoring RBC deformability of elite athletes during the course of the year may be suitable to detect for autologous blood doping.  
    But first it was necessary to test for factors that possibly influence deformability in endurance athletes. Among these were age, ethnicity, gender, estrogen levels and training volume.  
    The major results revealed increasing RBC deformability from pre-puberty to adulthood. Further, female athletes who used hormonal contraceptives and who thus showed reduced estrogen levels showed reduced RBC deformability compared to female athletes without hormonal contraception (-HC). An acute response of RBC deformability to increasing estrogen levels was not detected concluding a chronic impact of estrogen on RBC deformability. Both, male and female athletes (-HC) showed higher deformability values compared to respective non-athlete control groups, indicating a correlation of endurance exercise and RBC deformability. RBC deformability did not differ between male athletes and female athletes – HC but deformability values were significantly higher in male athletes compared to female athletes + HC. Female Asian and black athletes (all – HC) showed reduced RBC deformability compared to white female athletes – HC. Also, male Asian and black athletes showed reduced RBC deformability compared to white male athletes.  
    The recent data indicated that RBC deformability is influenced by some variables such as gender or ethnicity. According to the recent data it is suggested to monitor individual RBC deformability values longitudinally to detect abnormalities possibly occurring after autologous blood doping.

    Voir le projet à propos de Determination of red blood cell deformability in athletes during the course of the year: Considering gender, ethinic and traning conditions
  • Development of Reliable Blood Tests for the Detection of Gene Doping after Intramuscular Injection of Recombinant Adeno-Associated Viral Vectors

    Development of Reliable Blood Tests for the Detection of Gene Doping after Intramuscular Injection of Recombinant Adeno-Associated Viral Vectors

    By

    Investigateur principal
    R. Snyder

    University of Florida, Nantes University

    États-Unis, France   ―   2011   ―   Complété

    Sommaire

    Code: 11C9RS

    Aim 1: Assay optimization

    We will evaluate a combined assay format that is based on real-time PCR and ITC readout with a nested PCR pre-step to improve sensitivity. The current single-step qPCR assay has a sensitivity of 3 copies for the macaque Epo cDNA in the presence of 500ng - 1 OOOng macaque gDNA. A qPCR assay has been developed to the homologous locus in the human Epo cDNA with a sensitivity of 10 copies in 500ng human gDNA. A nested PCR assay has been developed for the human Epo cDNA with a sensitivity of 10 copies in 1250ng of human DNA. We will evaluate the enhanced sensitivity of nested PCR combined with the automation and rapid results of qPCR with the aim of reaching a sensitivity of less than 5 copies in 500ng genomic DNA. We will also examine the feasibility of utilizing the ITC assay format with the nested+qPCR approach. Once the assay is developed and tested using plasmids and virions spiked into gDNA and human blood, we will evaluate samples obtained directly from transduced macaques, and macaque PBLs spiked into na"fve human blood. The SV40 polyA site, which is not present in the human genome, but will be present in the rAAV vector used here, is an ideal target since there is no competition with endogenous sequences. The SV40 assay was previously developed [1Jfor the macaque studies and is considered to have the best sensitivity; it will serve as a reference for optimizing the hEPO Exon3-4 assay. Controls (ITC format) will be developed for each assay.

    Aim 2: Assay validation

    New or revised clinical diagnostic methods must be validated: defined as the process by which it is established, by laboratory studies, that the performance characteristics of the method meet the requirements for the intended analytical application. Components of validation involve quality control (QC) and quality assurance (QA). We will perform analytical validation of the human Epo assay to ensure specificity, sensitivity, and ruggedness (multiple labs, multiple operators, repeats and replicates). This will involve drafting test records, along with assay specifications, reagent preparation logs, and a validation plan, and executing the assay(s) several times with several replicates in Florida and Mainz. Data will be captured and evaluated statistically to determine the assay performance criteria. For pre-clinical performance validation, we will evaluate spiked (using plasmid DNA) human blood samples with respect to: sex, age, race, medical history (if available), exercise status, general health, and prescription drugs (if known). The rate of false positives and false negatives will be established by testing a statistically significant number of samples. We will screen up to 100 blood samples (50 for each lab in Florida and Mainz) for false positives in order to get an idea of the specificity of our procedures. The Simon Lab will contribute 100 human samples (Germans), and if available, substitute some of the German samples with samples of other ethnicities.

    The assay validation activities support the documentation for eventual regulatory submission and eventual manufacture of an in vitro diagnostic test (IVD) kit. Ultimately, data from the assay development, analytical validation, and pre-clinical performance validation studies will be documented along with a description of each kit (with all required components) in a form suitable for regulatory submission.

    As for regulatory capability and expertise, in addition to his faculty appointment and research activities described in this proposal conducted in the Department of Molecular Genetics and Microbiology, Dr. Snyder is the Director of the Center of Excellence for Regenerative Health Biotechnology at University of Florida (UF CERHB, http://www.cerhb.ufl.edu/ ). Established in 2003, the UF CERHB is committed to translational research in many different biotechnological fields including viral vectors for gene therapy. UF CERHB's biopharmaceutical development operation, offers a wide range of cGMP-compliant biopharmaceutical manufacturing and testing services to the biotechnology industry and to biomedical research institutions. Furthermore, Dr. Moullier runs a similar operation in Nantes called ATLANTIC BIO GMP (ABG). Resources are available (on a fee-for-service basis) at UF CERHB and ABG, Nantes for anti-doping PCR assay kit manufacturing.

    Main Findings

    It is crucial to develop reliable test methods for the detection of gene doping, given that some members of the sports community are seeking for gene transfer technology to improve exercise performance. Based on previous work we established a ´nested real-time PCR´ assay. This is an assay based on the PCR technology which is used in criminology and well-known in the court of law for the identification of genetic material in samples from sites of crime. We adapted this technique to detect single erythropoietin (EPO) DNA molecules that had been introduced into the body by means of gene transfer. Due to its high sensitivity, our technique is principally able to detect genetic modifications of certain parts of the body in conventional blood samples. Here we aimed at providing evidence of the high sensitivity and specificity of our refined procedure that now enables quantification of the artificial DNA in the blood stream.

    Through an inter-laboratory study between Nantes (France), Gainesville (Florida, USA), and Mainz (Germany) two nested real-time assays were validated and utilized for an in vitro blinded study. Both assays showed unique sensitivity and specificity in a large dynamic range. According to the nested assay protocol the detection of ~1 copy of circular transgene molecule in a background of 500 ng gDNA is possible reliably. In a blinded in-vitro study the reliability of the assays to detect between 1000 – 2 copies of transgene molecules and non-template control was proven.

    To validate the suitability of the nested real-time assays for the detection of gene doping a non-human primate study was conducted. Two macaques were injected intramuscularly with a recombinant adeno-associated virus serotype 8 (rAAV8) vector harboring human EPO cDNA sequence. One macaque served as non-injected control. The vector was promoterless to avoid transgene expression. Following the injection of 2.5 x 1011 viral genomes/kg, the transgene molecules were detectable 8-14 weeks.

    The high sensitivity of the nested qPCR assay along with the specificity for transgene detection is essential for gene doping surveillance. The assay can be adapted to other gene doping candidate genes.

    Voir le projet à propos de Development of Reliable Blood Tests for the Detection of Gene Doping after Intramuscular Injection of Recombinant Adeno-Associated Viral Vectors
  • Development of Ultrasensitive DNA Aptamer-Based Tests for Pharmaceutical Grade Recombinant Human Growth

    Development of Ultrasensitive DNA Aptamer-Based Tests for Pharmaceutical Grade Recombinant Human Growth

    By

    Investigateur principal
    J. Bruno

    Operational Technologies Corporation

    États-Unis   ―   2011   ―   Complété

    Sommaire

    Code: 11B1JB

    Operational Technologies Corp. (OpTech) has already demonstrated and published (BrunoJ.G., et al. J. Biomolec. Techniques, In Press, 2011) the ability to develop aptamers (surrogate antibodies composed of DNA) which can discriminate synthetic (recombinant) from natural human growth hormone (hGH) with initial funding from WADA. The aptamers developed by OpTech detect minor amino acid modifications and differences added by E. coli host cells as noted by Hepner et al. (2005 and 2006) to research grade synthetic hGH. Under this follow on grant proposal, OpTech will develop a new set of discriminatory aptamers against one or more pharmaceutical grade recombinant hGH targets (Genotropin, Norditropin, etc.). OpTech has recently demonstrated ultrasensitive (sub-picogram/ml) detection of hGH with some of its original hGH aptamers in an aptamer-magnetic bead sandwich electrochemiluminescence (ECL) format. ECL is already used by Roche Diagnostics for ultrasensitive detection of numerous clinical analytes. Therefore, OpTech will develop several combinations of capture and reporter aptamers to detect pharmaceutical hGH at sub-pg levels. Finally, because ECL is a laboratory-bound technique, OpTech will investigate the potential for presumptive field testing for synthetic hGH in aptamer-based lateral flow test strips using blood or urine samples for preliminary screening of athletes. To enhance sensitivity, OpTech will explore the use of quantum dots (QDs) and fluorescent nanoparticles (FNPs) along with a UV penlight to enhance visual detection of synthetic hGH in lateral flow test strips. Disposable low pressure size-exclusion chromatography columns may be needed to remove creatinine and urea in serum and urine prior to aptamer-based assays. These substances appear to denature aptamer secondary and tertiary structures which are critical to proper folding and binding of aptamers to hGH and other targets. This is anticipated to be a two year project. 

    Main Findings: 

    Operational Technologies Corp. (OpTech) was unable to obtain Genotropin or Norditropin from Pfizer, Novo Nordisk, or other sources.  However, OpTech developed DNA aptamers against the oxidized peptide regions of Genotropin defined by Hepner et al. (2005 and 2006) and thought to be potential sites for discrimination of recombinant vs. natural hGH in ~ 2% of Genotropin molecules. OpTech screened these aptamers against research-grade rhGH and natural pituitary hGH and identified several candidate aptamers (e.g., Hep 5-6R, Hep 6-6R and Hep 6-12R) which may be able to discriminate Genotropin from natural hGH.  However, without access to authentic Genotropin, OpTech could not test this hypothesis fully.  Therefore, OpTech elected to use the remaining funds to explore new and potentially even better approaches to detecting hGH abuse in athletes with aptamer-based assays.  These new approaches were: 1) Development of aptamers to bind human IGF-1 and PIIINP which are both long-lived serum biomarkers of rhGh use.  This work resulted in development of a preliminary enzyme-linked IGF-1 aptamer-magnetic bead sandwich assay which functioned in pure human serum with a lower limit of detection of ~ 30 ng/mL and linear detection to > 1,000 ng/mL.  The top-ranked IGF-1 aptamer candidates (3F and 25R) may bind a region of IGF-1 that is accessible even when IGF-1 is bound by its binding proteins in serum.  Unfortunately, these IGF-1 aptamers also demonstrated significant cross-reactivity with Brain Natriuretic Peptide (BNP), bone collagen Helical Peptide (HP) and rhGH, but much lower affinity for C-telopeptide (CTx) or N-telopeptide (NTx) of bone collagen.  Preliminary data also indicated that development of a PIIINP aptamer assay with linear quantification in the high to mid-ng/mL range was possible using at least 3 different aptamer candidates identified during ELISA-like screening (ELASA).
    2) Development of aptamers against specific peptide regions of the 20kD and 22kD isoforms of hGH to emulate the current ratiometric immunoassay.  OpTech developed aptamers against the 15-amino acid region (EEAYIPKEQKYSFLQ) of 22kD hGH which is not present in 20 kD hGH and also developed aptamers against the fused flanking regions (DTYQEFNPQTSL) resulting from alternative splicing to enable discrimination of unique regions on each isoform of hGH.  Two lead candidates designated “Splice 20-14R and Splice 22-5F” were identified for potential future ratiometric assay development.Both approaches appear promising and, if fully developed, would have the advantage of overcoming lot-to-lot variability associated with antibodies and immunoassays, because aptamer DNA synthesis from known sequences is a very high fidelity process.

    Voir le projet à propos de Development of Ultrasensitive DNA Aptamer-Based Tests for Pharmaceutical Grade Recombinant Human Growth
  • Direct gene doping detection: generation, characterisation and validation of a synthetic reference material for routine testing

    Direct gene doping detection: generation, characterisation and validation of a synthetic reference material for routine testing

    By

    Investigateur principal
    A. Baoutina

    Commonwealth of Australia

    Australie   ―   2011   ―   Complété

    Sommaire

    Code: 11C12AB 

    The anti-doping community is focusing efforts on developing methods to detect gene doping, a new threat to the world of sport. 
    Methodology with potential to detect ‘doping’ genes in blood samples from athletes has recently been developed by us and other researchers. It involves PCR assays targeting intronless cDNA sequences that are present in doping genes but absent in intron-containing endogenous genes.  Acceptance of this methodology for routine gene doping testing requires reference materials as controls to ensure the method performs as intended. A positive control containing the cDNA sequence for the candidate doping gene is commonly used in method development. Inadvertent cross-contamination of a tested sample with this type of control would lead to a false positive test result. Hence, it is not suitable for routine testing because of legal implications. 
    We propose to develop a DNA reference material for a positive control in gene doping testing that will overcome this problem. Using erythropoietin as a model doping gene, we will produce a reference material that will be detectable by the PCR assays with similar specificity and sensitivity as the doping gene. However, the reference material and gene doping products will differ, allowing easy discrimination between true positive and false positive test results. We will characterise this reference material for purity and quantity using latest technologies including digital PCR and next generation sequencing. In addition, using this reference material we will in vitro validate the complete erythropoietin gene doping detection method from sample processing to PCR detection. 
    This model system will serve as a prototype for preparing reference materials for detecting doping with other candidate genes. 
    The proposed research is crucial in the development of a routine method for direct detection of gene doping and for ensuring the method is reliable, reproducible and robust and will withstand legal scrutiny. 

    Main Findings: 

    The anti-doping community is focusing efforts on developing methods to detect gene doping, a new threat to the world of sport. Recently, methodology with potential to detect ‘doping’ genes in blood samples from athletes has been developed by us and other researchers. 
    Acceptance and implementation of this methodology for routine gene doping testing requires Reference Material (RM) as a control to ensure the method performs as intended. Existing ‘in-house’ controls based on complementary DNA (cDNA) for targeted genes will not withstand legal scrutiny since any cross-contamination will generate ‘false positive’ test results. 
    In this project, we generated and characterised a DNA RM that will overcome this problem. Using EPO as a model doping gene, we produced three forms of the RM. Each form is detectable by the PCR assays that target a doping EPO gene. However, the products generated in these assays from the RM and a doping gene differ, allowing easy discrimination between true positive and ‘false positive’ test results. We characterised these three forms of the RM for purity, quantity and stability, and studied their performance in gene doping detection assays. Finally, the three forms were in vitro validated in the complete EPO gene doping detection method from sample processing to PCR detection. 
    This model system will serve as a prototype for preparing RM for detecting doping with other candidate genes. The produced RM is crucial in the development and acceptance of a routine test for direct detection of gene doping and for ensuring the method is reliable, reproducible and robust and will withstand legal scrutiny.

    Voir le projet à propos de Direct gene doping detection: generation, characterisation and validation of a synthetic reference material for routine testing
  • Direct urinalysis of steroids

    Direct urinalysis of steroids

    By

    Investigateur principal
    P. Van Eenoo

    Ghent University

    Belgique   ―   2011   ―   Complété

    Sommaire

    Code: 11A17PV

    Anabolic steroids are the most frequently detected prohibited substances in sports. Analysis for these substances is routinely performed using gas chromatography-mass spectrometry (GCMS) and liquid chromatography mass spectrometry (LC-MS). Although the detection capabilities of LC-MS are limited for the detection of steroids with androstanediol as a back bone to their structure, LC-MS is often more sensitive for many other steroids. Moreover, recently several publications have shown that LC-MS can detect steroids (glucuronides) directly in urine without any sample preparation.

    The advantages for such a direct urinalysis are multi-fold. It reduces costs, required volume of sample and analysis time, but also it allows for the direct detection of intact conjugated steroids rather than the liberated steroid molecules after hydrolysis.

    In the past several small scale attempts have been made to detect these intact steroid conjugates in urine. These attempts were quite successful, but did not meet WADA’s minimum required performance limits. Recently however several scientific improvements have been made, including more sensitive instruments, optimized mobile phase compositions (e.g. methanol
    instead of acetonitrile), which now allow for the detection of several steroids well below WADA’s MRPL. These preliminary results (e.g. 19-norandrosterone glucuronide) show that the direct urinalysis of steroid conjugates at concentrations at or below the MRPL is achievable.

    Main Findings: 

    The aim of this project was to study intact conjugated anabolic steroids in urine in comparison with the traditional methods where the aglycones are detected after enzymatic hydrolysis. This approach permitted the detection of anabolic steroids misuse by liquid chromatography mass spectrometer since the glucuronide and sulfate groups are easy to ionize by ESI. Consequently, steroids with a sulphated or glucuronidated androstane framework could be detected. Research resulted in the development of a multi-target analytical method for the screening of different exogenous anabolic steroids and also for the quantification of endogenous anabolic steroids.

    The use of a dilute-and-shoot strategy allowed to minimize sample preparation yielding a short turnaround time. Additionally a small volume of urine can be used. This is a great advantage compared with traditional methodologies where liquid-liquid extraction or solid phase extraction after enzymatic hydrolysis and detection by LC-MS or GC-MS (after derivatisation step) is applied.

    The use of excretion studies or synthesis in vitro are of great interest since the number of conjugated anabolic steroids commercially available is still very low. With this methodology new conjugated anabolic steroids were detected and included in the multitarget method.

    Voir le projet à propos de Direct urinalysis of steroids
  • Effects of glucocorticoid during repeated bouts of high-intensity exercise

    Effects of glucocorticoid during repeated bouts of high-intensity exercise

    By

    Investigateur principal
    M.C Do

    Laboratory CIAMS

    France   ―   2011   ―   Complété

    Sommaire

    Code: 11D7MD 

    This project, which constitutes a follow-up from two previous works funded by WADA aims at widening our understanding of the effects of glucocorticoids (GC) on muscle function, exercise performance, postural control and health risks. Indeed, we demonstrated in our previous works that short-term but not acute GC administration improves performance during endurance exercise lasting at least 40 minutes, without any gender effect. However, no study, to our knowledge, has focused on the ergogenic effects of GC during repeated bouts of high-intensity exercises. In the same way, whether the numerous deleterious effects of chronic (>1 month) GC intake are well known, there is no consensus on health risks after short-term (1 week) systemic GC intake. 
    We therefore propose to study whether short-term GC administration would improve performance during repeated bouts of high-intensity exercise. In parallel, we will investigate with complementary methods the repercussions of GC administration on biomechanical (especially the magnitude of the braking of the fall during the swing phase), and physiological parameters (cardio-respiratory, muscular and inflammatory) in order to assess both GC ergogenic effects and health risks induced by short-term high dosage treatment.

    Main Findings: 

    In the project “Effects of glucocorticoid during repeated bouts of high-intensity exercise” we tested the ergogenic effects and health risks of short-term GC administration. Physiological and biomechanical parameters were analyzed. Several results can be highlighted: 
    - No ergogenic effect of short-term systemic GC (i.e. 60 mg prednisone/day/7 days) was found during repeated bouts of brief intense exercise. Muscle oxygenation parameters measured with the near infrared spectroscopy technique were not altered by short-term GC administration at rest and during repeated bouts of high-intensity exercise. These suggest that GC treatment had no effect on the blood oxygen transport capacity and on the muscle oxygen extraction during exercise. The unaltered oxygen availability at the muscle level seems to be in accordance with the lack of improvement in performance during the last sequence of hopping with the GC treatment.  
    - Regarding hormone responses during exercise, while no change was found in saliva testosterone, GC intake induced changes in saliva cortisol and DHEA concentrations. In parallel, blood IL-6 and IL-10 were altered at rest and during the exercise performed. It is interesting to note that the anti-inflammatory effects of prednisone were maximal and stable from the beginning of treatment, in the resting and exercise conditions. However, hormonal concentrations continued to decline during short-term intake. Lastly, our study shows that short-term prednisone treatment affects the circadian pattern of saliva DHEA but not testosterone in our recreationally trained subjects.  
    - Regarding baroreflex sensitivity (BRS), heart rate (HR) and systolic blood pressure (SBP) variability (HRV, SBPV) short-term GC intake did not change SBP. However, a low frequency (LF) SBPV increase associated with a LF-BRS decrease and a HR increase was observed, indicating a sympathetic cardiovascular stimulus.  
    - Regarding EMG activities in the ankle extensors EMG during single leg hopping, and balance control during single stance of the first step in gait initiation, no GC effect was noted compared to placebo.

    Voir le projet à propos de Effects of glucocorticoid during repeated bouts of high-intensity exercise
  • Evaluation of Solid Phase Microextraction for Improved Multi-Residue Extraction and Analysis of Prohibited Substances by LC-MS/MS

    Evaluation of Solid Phase Microextraction for Improved Multi-Residue Extraction and Analysis of Prohibited Substances by LC-MS/MS

    By

    Investigateur principal
    J. Pawliszyn

    University of Waterloo

    Canada   ―   2011   ―   Complété

    Sommaire

    Code: 11A3JP 

    Recent advances in liquid chromatography–mass spectrometry (LC-MS) have opened the possibility of converting many of the doping control analysis methods to LC-MS platforms. This would increase flexibility and selectivity for many analyses, while obviating the need for derivatization in most cases. A limitation to this switch is the established sample preparation strategies required for the numerous doping control methods. Developed for GC-MS analysis, they are time consuming and not always appropriate for LC-MS analysis. While the LC-MS technology holds the promise of providing a universal screening tool, the varied requirements for sample preparation for the numerous tests limit this potential. Professor Pawliszyn's group has long recognized the bottle-neck that sample preparation presents for the analytical laboratory, and have made significant strides in developing solid phase microextraction (SPME) technology to simplify sample preparation for both GC-MS and LC-MS, while maintaining sensitivity and enhancing options for automation.  
    In this project we will evaluate automated SPME technology as a universal sample preparation strategy, coupled with LC-MS as a universal tool for identification and quantification of prohibited substances. We will develop validated methods for urine analysis for a range of prohibited substances from the S1, S3, S4, S5, S6, S7, S8, S9 and P2 categories. We will apply enzymatic deconjugation of phase II drug metabolites as required and investigate guidelines for confirmatory analysis. SPME technology is also readily applicable to plasma and whole blood analysis and has significant advantages relative to SPE. We will evaluate the performance of the system in these matrices as well. At the conclusion of the project we will have sufficient data to evaluate the suitability of automated SPME coupled with LC-MS as a universal tool in prohibited substance screening. If judged suitable, it will be immediately applicable for introduction to the screening program in WADA accredited facilities. 

    Main Findings: 

    • The potential of automated solid phase microextraction (SPME) in thin film geometry as simple and convenient sample preparation approach for urine, plasma and blood analysis was demonstrated.
    • SPME conditions for each of the studied matrices were carefully optimized. The effect of experimental parameters such as pH, ionic strength, centrifugation and temperature was investigated.
    • Protocols for the multiclass analysis of 110 and 25 prohibited substances in urine and plasma, respectively, were developed and validated.
    • In the case of urine, 100 out of 110 compounds showed R2 above 0.991, intra and inter day precision was below 20 % in most cases, and in terms of accuracy only 6 compounds exhibited more than 20 % deviation from their nominal concentration value. Regarding LOQ, only 15 out of 110 compounds did not meet the MRPL values stipulated by WADA; however, as presented in the final report, by using a more sensitive mass spectrometry analyzer WADA requirements can be fulfilled.
    • In the method developed for plasma analysis, satisfactory results in terms of linearity (R2> 0.99), inter and intra-day accuracy (85 – 130 %), precision (<20 %) and limits of quantitation (0.25 – 10 ng/mL for most compounds) were found.
    • The suitability of the automated system to incorporate a hydrolysis step before SPME extraction was also verified.
    • The most important advantages of SPME in doping controls can be listed as follows:
    1. Minimum sample handling before SPME extraction. No need of centrifugation or protein precipitation (no clogging issues as in SPE).
    2. High-throughput analysis. The automated 96 Concept system allows simultaneous preparation of 96 samples.
    3. Efficient sample clean-up. Elimination or reduction of possible ionization suppression or enhancement effects.
    4. No breakthrough volume issues. The open bed geometry of SPME allows simultaneous quantitation of a wide range of substances without concerning about extraction phase saturation.

    Voir le projet à propos de Evaluation of Solid Phase Microextraction for Improved Multi-Residue Extraction and Analysis of Prohibited Substances by LC-MS/MS
  • GC/C/IRMS analysis of testosterone and nandrolone metabolites after the administration of testosterone enanthate and nandrolone decanoate in healthy volunteers

    GC/C/IRMS analysis of testosterone and nandrolone metabolites after the administration of testosterone enanthate and nandrolone decanoate in healthy volunteers

    By

    Investigateur principal
    A. Rane

    Karolinska Institutet

    Suisse   ―   2011   ―   Complété

    Sommaire

    Code: 11A25AR 

    Anabolic androgenic steroids (AAS) behave differently in the human body. The human organism deals with these compounds differently in respect of uptake, distribution into different organs, metabolism and excretion. We recently demonstrated that ¾ of Oriental people have a severely compromised capacity to excrete testosterone in the urine compared to only 10 % in people from the west. This is a confounder in the doping test program and therefore it is urgent to find new biomarker and approaches. 
    In the way towards personalised test programmes, Bayesian inference techniques are known to suit particularly well. Another approach is to verify the origin of testosterone by using IRMS. 
    To further improve the new individualised steroid profile passport, we will conduct humanstudies with nandrolone and different doses of testosterone in order to assess the sensitivity and specificity of IRMS and to learn more how administrated AAS are metabolized.

    Main Findings:

    The urinary testosterone glucuronide to epitestosterone glucuronide (T/E) ratio is a biomarker included in Steroid Module of the Athlete Biological Passport (ABP) which has improved doping tests for steroids. However, the ratio is greatly affected by a genetic deletion polymorphism in the UGT2B17 enzyme which is the major catalyst of testosterone metabolism. Suspect urine doping tests are further analyzed with gas chromatography-combustion-isotope ratio mass spectrometry (GC/C/IRMS) to determine the origin of the androgen.  
    We investigated the sensitivity of the steroidal module and the IRMS analysis in subjects administered with three doses of testosterone enanthate (500, 250, and 125 mg), in relation to the UGT2B17 polymorphism. All subjects carrying the UGT2B17 enzyme reached the traditionally used threshold, a T/E ratio of 4, after all three administered doses, whereas none of the subjects devoid of this enzyme reached a T/E of 4. However, using the ABP and IRMS analysis, all three doses generated a positive result with a high degree of sensitivity. Our results demonstrate that administration of one single dose, as small as 125 mg testosterone enanthate, could be detected with the ABP in combination with IRMS. Since IRMS is sensitive to testosterone doping independent of UGT2B17 genotype, also very small changes in the steroidal passport should be investigated with IRMS.  In our study of the excretion profile of nandrolone and the 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) metabolites after one single i.m. dose of 150 mg nandrolone decanoate (ND) to healthy volunteers we were able to demonstrate that 19-NA is detectable for 9 months in about half of the individuals. This is the first study where GC-C-IRMS analysis has been performed after an i.m administration of ND in a controlled study group. The absolute δ19-NA (‰) was in the same range as observed previously, with values between -29.1 -and -34.7 in 19-NA positive samples confirming the presence of 19-NA of exogenous origin. The use of the well characterized androsterone (A) as an endogenous reference compound or any other compound not modified by exogenous administration is also possible. Here we show that 11-oxoandrostenedione and pregnanediol may also serve as endogenous reference compounds to detect exogenous origin of 19-NA 3-9 months after one single dose of 150 mg ND. Interesting to note, exogenous 19-NA was traced in GC/C/IRMS in a sample where 19-NA was below the decision limit.   
    In summary, GC/C/IRMS analysis confirmed the presence of exogenous derived steroids in both our studies, regardless of UGT2B17 genotype, dose, and time, further supporting the strength of using this methodology. 

    Voir le projet à propos de GC/C/IRMS analysis of testosterone and nandrolone metabolites after the administration of testosterone enanthate and nandrolone decanoate in healthy volunteers
  • Identification and detection of LH in urine

    Identification and detection of LH in urine

    By

    Investigateur principal
    C. Goebel

    Commonwealth of Australia

    Australie   ―   2011

    Sommaire

    Code: 11B8CG

    Luteinizing hormone (LH) is a naturally occurring hormone which is secreted by the pituitary gland. In males LH stimulates testosterone production by the testes. Recent research has proven that the monitoring of LH is a valuable tool for both the detection of anabolic steroid abuse; where suppression of LH is observed, and gonadotrophin releasing hormone abuse, where elevation of LH levels is observed. The ability to use LH as a marker for the detection of the abuse of other doping substances is limited by the currently available testing techniques. There are numerous commercially available immunoassays but these are only marketed for the testing of serum samples. The use of the available immunoassays for monitoring of LH in urine needs to be carefully cross validated for comparison to ensure suitably of the results for anti doping.

    Furthermore to better understand why there are such differences in the concentrations detected by different immunoassays it is proposed to purify and sequence from urine both naturally present LH as well as from recombinant LH excretion studies. The proposed research will harmonize the measurement of LH in urine for anti doping as well as gain a better understanding of the measurand which will lead to better detection methodologies.

    Main Findings: 

    The Immulite and Delfia assay are able to detect LH in urine even after extended periods of storage at 40°C, 21°C, 4°C and -20°C. The results for the Delfia stability study reflect what was observed for the Immulite stability study, that LH is unstable at room temperature but although it is also unstable when frozen, quantifiable amounts are still able to be detected with the Delfia assay and the Immulite assay. Statistical analysis of 1000 athlete samples gave correlation factors for both the Immulite and the Delfia, enabling a more accurate comparison of results between the two assays. This will be particularly useful to the anti-doping community as different laboratories use only one or the other of the assays for detecting LH in urine. For anti-doping purposes urine is stored frozen which is where urinary endogenous LH is degrading. Sequencing of the beta subunit of LH revealed the C-terminal and N-terminal of the protein are still largely intact meaning that changes to the protein chain must be occurring within the protein backbone. The tertiary structure of LH may be allowing certain areas to more readily degrade due to turns and disulphide bond placements in the structure as well as the influence of post translational modifications such as the single N-linked glycan on the beta subunit.

    Voir le projet à propos de Identification and detection of LH in urine
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