Projets de recherche

Code: 22C12MH

An emerging concern regarding the misuse of anabolic doping substances in sports is “muscle memory” – as skeletal muscle that has previously been exposed to an anabolic prohibited substance may adapt more readily to retraining. While this phenomenon has been demonstrated in rodents, the underlying mechanisms as well as whether this applies to humans remain unknown. The relevance of studying muscle memory induced by prohibited substances is clear when considering the current anti-doping regulations. One can imagine a scenario where an athlete is banned from competitive events for a few years, but upon return to competitive sport still enjoys an advantage in retraining potential because of anabolic compound-induced muscle memory.

This project will elucidate whether prior treatment of the two commonly misused prohibited anabolic compounds, clenbuterol or testosterone, induces muscle memory and thus improves the hypertrophic response to subsequent resistance training. To this end, two longitudinal randomized placebo-controlled trials will be conducted in healthy volunteers undergoing periods of resistance training. The project will utilize state-of-the-art methodologies to address aspects of myocellular addition, hypertrophy and myocellular reprogramming in muscle biopsies collected during the trials.

Code: 22D05KC

With the increasing participation of female athletes in international competitions, there is growing interest in the specificities of the elite female athlete. Indeed, the elite female athlete is subject to a menstrual cycle, with huge variations in estrogen and progesterone concentrations during the cycle. A relatively large number of elite female athletes suffers from menstrual disorders, often due to intensive training and eating disorders, with inhibition of their hypothalamic-pituitary-gonadal axis, resulting in very low estradiol and progesterone levels. Finally, approximately 1 in 2 high-level female athletes uses hormonal contraception, the estrogen-progestin pill (OOP) being the most frequently used. Female sex hormone levels therefore fluctuate greatly in elite female athletes, with likely a significant impact on blood and urine steroid profiles.

However, most of the time, there is only an approximate estimation of the cycle phase, without direct blood female sex hormones and precursors analysis and if any, on a punctual way. We therefore propose to dose these hormones on a longitudinal way in elite non-hyperandrogenic female athletes, taking into account the duration of the MC, menstrual disorders or the use of OOP, in order to assess their direct impact on the blood steroid profile, in particular on testosterone (TES) and androstenedione (4-AEN), the target compounds selected by WADA for the blood steroid profile. As the environment of the athlete directly modulates the secretion of these female sex hormones, and consequently the steroid profiles, we will in parallel quantify the training load and food intake thanks to questionnaires and investigate the blood level of TSH, T3, prolactin, leptin, DHEA and cortisol, as well as the body composition during the different hormonal status.

Code: 22D02RF

The goal of our research is to investigate the impact of altitude training on blood values in elite athletes preparing for a major competition, with special focus on the biomarkers considered in the framework of the Athlete Biological Passport (ABP). Testing the hypothesis that hypoxic training is related to hematological variations would allow the present ABP model to be refined, and its efficacy strengthened. Our study would challenge the complexity of confounding factors affecting the interpretation of the ABP in elite athletes. In addition, based on the current development of a multi-parametric model previously validated in elite cyclists to compare inferred and actual plasma volume (PV) variations, investigation of the potential confounding effects of altitude exposure, and pre-competition tapering phase, can provide additional experimental evidence towards future improvements of the ABP.

The main objectives of this study are the following: firstly, this study will allow to further investigate the hematological variables of the ABP before, during, after a 3-week altitude training camp and on days before and after a major competition (20 days after the return to see level); furthermore, the potential confounding effect of hypoxic exposure will be evaluated by measuring PV changes or inferring the latter changes from serum biomarkers that are sensitive to PV changes. Overall, our study aims at improving the ABP in its current form and at evaluating the possible implementation of additional biomarkers.

Code: T22M01RTRV - Part 2

12 hours starting from any dose”, which is considered as the cut-off between maximal therapeutic dosagesfor athletes benefiting from a therapeutic use exemption and doses at which a doping effect could begin to be expected from systemic exposure [8]. The WADA established a urinary concentration

Code: T22M01RTRV - Part 1

Salbutamolwas included in the prohibited list of the World Anti-Doping Agency (WADA) in 2004. While systemic salbutamol is banned, inhaled salbutamol is permitted but with dosage regimen restrictions. The dose should indeed not exceed “1600 µg over 24 hours in divided doses not to exceed 800 µg over.

Code: 22D06MT

Several cases of so-called sample swapping have been detected in recent years. During sample swapping an athlete substitutes the presumable positive doping control sample by another negative urine sample in order to circumvent an adverse analytical finding. For the exchange of urine, a sample from the same individual or from a different individual may be used. While the latter can result in a significantly different steroid profile, employing a urine sample from the same individual collected prior to administration of a doping agent will not show any differences in the steroid profile. Here it can be expected that the stored clean sample will be used several times and that this may result in steroid profiles with an atypical similarity. Two cases of this type of sample swapping have already been detected, but only by chance as the similar samples were analyzed in the same laboratory in a timely manner. 
The aim of this research project is the development of a screening tool based on machine learning and artificial intelligence which will enable to detect steroid profiles with an atypical similarity in all steroid profiles determined world-wide in different accredited doping control laboratories. The developed software will be able to search within the existing profiles for similar ones and will be trained to compared new entries to the dataset to existing ones in order to indentify highly similar patterns. Employing artificial intelligence will enable to train the software to become highly sensitive, selective and robust. In order to confirm potentially similar samples to belong to the same athlete, DNA analysis of these urine samples will be applied where applicable.

Code: 22C05MT

Higenamine is a non-selective β2-agonist, which has been described as a key component of a great variety of natural plants such as Nandina domestica, Tinospora crispa, and Annona squamosa. Although higenamine has never been approved as a drug by the US Food and Drug Administration (FDA), it plays an important role in traditional Chinese herbal medicine (it has been approved for clinical research by the China Food and Drug Administration - CFDA), and has been found to be an ingredient - often unlabeled - of different weight loss and sports supplements, which has been suspected or proven to have caused cases of unintentional anti-doping rule violations.
Within the scope of a previous elimination study aiming at the urinary quantification of higenamine after administration of tropical fruit plants from the Annonaceae family, it could be shown that single-dose administrations of these fruit species are rather unlikely to lead to AAFs in sports. The aim of this project is to conduct further investigation which complement the previous datasey. For that purpose, stability evaluation of componuds of interest, and specific contribution of the different higenamine conjugates will be performed. Besides, two different administrations studies with a total of 6 healthy volunteers  (3 x ♂, 3 x ♀) are planned. Each participant will eat 3 servings on Annona fruit puree with 24 h (8:00 am, 6:00 pm, and next day 8:00 am) and, at after washout, a single dose of two different higenamine-containing nutritional supplements. Urine samples will be collected up to three days following administration in both study phases, and comprehensive analyses are planned to support result management and decision-making processes in case of higenamine findings in sports drug testing programs, preferably by means of new potential biomarkers of plant-derived higenamine administrations.

Code: 22B06XZ

Upon our previous research, a variant in the EPO gene can encode a variant EPO (VAR-EPO) which has a similar molecule weight with recombinant EPO (rEPO), thus cannot be distinguished using the current method of rEPO analysis. Though WADA has established a detailed procedure for investigation and further analysis, it is a burden for both laboratories, Testing Authoity and WADA, nevertheless, rEPO abused by this variant carriers can be hardly detected. For this situation, we are going to develop an effective confirmation method that can discriminate the wild-type EPO, VAR-EPO and rEPO directly, by removing or eliminating the detection of VAR-EPO using the VAR-specific antibody. Two methods will be developed and validated in this project:: reverse-normal immunopurification and step-recognition western blotting. The rEPO administration study on individuals who carry this varient will also be conducted. The collected positive urine and blood samples will be used to evaluate the method. With out goals, the new method can not only protect the "clean" athlete with that variant but also effectively penalize the rEPO abused athelete whether he or she carries that variant. Another significant advantage, this method would be easily adopted by other WADA accredited anti-doping laboratories.

Code: 22B05PC

Erythropoietin receptor agonists (ERAs), e.g. darbepoetins (dEPO), erythropoietins (EPO), EPO-Fc were listed in WADA's Prohibited List under Class S2.1. Traditional polyacrylamide gel-electrophoretic analytic methods were applied by most of the WADA certified laboratories for ERAs detection for the last 20 years. In this project, a novel photoclick hydrogel electrophoretic and in situ immunoblotting method for the screening of ERAs in urine and blood samples of athletes will be developed with high sensitivity and high throughput. A tetrazole-functionalized photoclick hydrogel based chip will be designed first which can satisfy the processing of 15 samples simultaneously. Optimization of the parameters in SAR-PAGE and intensity immunoblotting assay will be carried out on this chip to realize the separation of ERAs, especially the distinguishment of endogenous EPO and recombinant human EPO )rhEPO). Along with the confocal microscope for image acquisition, the LOD of this method can be lower than 1 IU/L (plasma) and 0.1 IU/L (urine) with limited sample volumes. Meanwhile, the whole analysis time can be reduced within 6 hours for plasma samples. Finally, an intravenous administration of rhEPO drugs on healthy subjects will be carried out to verify the practicability of this new method.

Code: 22A10JP

There is a high demand for rapid screening methods using mass spectrometry (MS) that can decrease the turnaround time, cost, and limits of quantitation of existing methodologies. It is important to emphasize that appropriate sample preparation is required to perform proper sample cleanup and analyte enrichment. We are focused on using matrix-compatible SPME-based devices for direct immersion extraction of small molecules from biofluids and direct coupling to MS. In this context, matrix-compatible SPME-based devices have extraction phases comprised of high-capacity sorbent embedded in a polyacrylonitrile binder that ensures small molecules can be extracted while minimizing the co-extraction of macromolecules. This provides better performance and more sensitive analysis of a wide range of small molecules including many of those found on the 2022 Prohibited List. Futhermore, we are focused on couple SPME-based devices to MS via the microfluidic open interface (MOI) and coated blade spray (CBS) technology, as well as developing more efficient ways to separate isobaric/isomeric analytes in the gas phase before MS detection using ion mobility spectrometry (IMS). These developments are critical to decrease the detection limits and discern between permitted and prohibited substances while increasing the speed of analysis and the range of screened and quantified molecules. In this proposal, we build on this success and propose applying SPME technologies directly to MS which have been recently developed in our laboratory to further improve the speed of screening directly during sports events. In the long term, the goal of the team's research is to take advantage of ongoing advances to develop powerful new analytical technologies to assist in the ongoing fight against doping in sport, with an emphasis on lowering the detection limits to better distinguish between permitted from prohibited use, as well as improving the detection window of prohibited substances.