Erythropoietin and blood doping

ELECTROCHEMICAL BIOSENSOR FOR ERYTHROPOIETIN DETECTION IN ATHLETES

ABSTRACT Introduction: The cytokine erythropoietin (EPO) is a crucial hormone for producing RBCs, which carry oxygenated blood to the rest of the body. Objective: This paper aimed to create an electrochemical detection based on Fe2O3-NiO nanoparticles and graphene oxide to measure EPO levels in athletes’ blood. Methods: On a glassy carbon electrode, Fe2O3-NiO@GO was synthesized using the electrochemical deposition method. Results: The Fe2O3-NiO@GO/GCE was validated by structural characterizations using scanning electron microscopy (SEM). The Fe2O3-NiO@GO/GCE was found to be a suitable and stable erythropoietin biosensor with a linear range of 0-500 ng/l and a detection limit of 0.03ng/l in electrochemical tests using the DPV technique. Fe2O3-NiO@GO/erythropoietin was investigated as a biosensor for erythropoietin in athlete's plasma. Conclusion: The results showed that the values obtained for recovery (94.56% to 98.40) and RSD (2.01% to 3.22%) were acceptable, indicating that the suggested technique can be used as a practical erythropoietin biosensor in blood samples. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Synthetic Peptides in Doping Control: A Powerful Tool for an Analytical Challenge

Peptides are very diverse molecules that can participate in a wide variety of biological processes. In this way, peptides are attractive for doping, since these molecules can activate or trigger biological processes that can improve the sports performance of athletes. Peptide molecules are found in the official World Anti-Doping Agency lists, mainly in sections S2, S4, and S5. In most cases, these molecules have a very short half-life in the body and/or are identical to natural molecules in the body, making it difficult to analyze them as performance-enhancing drugs. This article reviews the role of peptides in doping, with special emphasis on the peptides used as reference materials, the pretreatment of samples in biological matrices, the instrumentation, and the validation of analytical methodologies for the analysis of peptides used in doping. The growing need to characterize and quantify these molecules, especially in complex biological matrices, has generated the need to search for robust strategies that allow for obtaining sensitive and conclusive results. In this sense, strategies such as solid phase peptide synthesis (SPPS), seeking to obtain specific peptides, metabolites, or isotopically labeled analogs, is a key tool for adequate quantification of different peptide molecules in biological matrices. This, together with the use of optimal methodologies for sample pretreatment (e.g., SPE or protein precipitation), and for subsequent analysis by high-resolution techniques (mainly hyphenated LC-HRMS techniques), have become the preferred instrumentation to meet the analytical challenge involved in the analysis of peptides in complex matrices.

To Be a Champion of the 24-h Ultramarathon Race. If Not the Heart ... Mosaic Theory?

This comprehensive case analysis aimed to identify the features enabling a runner to achieve championship in 24-h ultramarathon (UM) races. A 36-year-old, multiple medalist of the World Championships in 24-h running, was assessed before, one and 10 days after a 24-h run. Results of his extensive laboratory and cardiological diagnostics with transthoracic echocardiography (TTE) and a one-time cardiopulmonary exercise test (CPET) were analyzed. After 12 h of running (approximately 130 km), the athlete experienced an increasing pain in the right knee. His baseline clinical data were within the normal range. High physical efficiency in CPET (VO₂max 63 mL/kg/min) was similar to the average achieved by other ultramarathoners who had significantly worse results. Thus, we also performed genetic tests and assessed his psychological profile, body composition, and markers of physical and mental stress (serotonin, cortisol, epinephrine, prolactin, testosterone, and luteinizing hormone). The athlete had a mtDNA haplogroup H (HV0a1 subgroup, belonging to the HV cluster), characteristic of athletes with the highest endurance. Psychological studies have shown high and very high intensity of the properties of individual scales of the tools used mental resilience (62–100% depending on the scale), openness to experience (10th sten), coherence (10th sten), positive perfectionism (100%) and overall hope for success score (10th sten). The athlete himself considers the commitment and mental support of his team to be a significant factor of his success. Body composition assessment (%fat 13.9) and the level of stress markers were unremarkable. The tested athlete showed a number of features of the champions of ultramarathon runs, such as: inborn predispositions, mental traits, level of training, and resistance to pain. However, none of these features are reserved exclusively for “champions”. Team support’s participation cannot be underestimated. The factors that guarantee the success of this elite 24-h UM runner go far beyond physiological and psychological explanations. Further studies are needed to identify individual elements of the putative “mosaic theory of being a champion”.

Effect of erythropoietin on athletic performance: a systematic review and meta-analysis

Introduction

Athletes have attempted to glean the ergogenic benefits of recombinant human erythropoietin (rHuEPO) since it became available in the 1980s. However, there is limited consensus in the literature regarding its true performance-enhancing effects. In fact, some studies suggest there is no conclusive evidence; therefore, it is necessary to evaluate and quantify the strength of the evidence.

Objective

To determine the effects of erythropoietin on enhancing athletic performance.

Design

At least two independent reviewers conducted citation identification through abstract and full-text screening, and study selection, and extracted raw data on demographics, descriptions of interventions and all outcomes to predesigned abstraction forms. Outcomes were stratified by treatment periods and dosages. Study quality was assessed using the Cochrane Risk of Bias Tool and Cochrane Grading of Recommendations Assessment Development and Education (GRADE) scale. Where appropriate, quantitative analysis was performed.

Data sources

EMBASE, MEDLINE and SPORTDiscus were searched from their inception to January 2020.

Eligibility criteria

Trials that examined any enhancement in sport in healthy participants aged 18-65 using rHuEPO compared with placebo were included.

Results

Overall, there is low-to-moderate quality evidence suggesting rHuEPO may be more beneficial than placebo in enhancing haematological parameters, pulmonary measures, maximal power output and time to exhaustion independent of dosage. However, these improvements are almost exclusively seen during maximal exercise intensities, which may be less relevant to athletic competition conditions.

Conclusion

Due to heterogeneity among trials, more high-quality randomised controlled trials with larger sample sizes in conditions that mirror actual competition are needed to further elucidate these effects.

An effective erythropoietin dose regimen protects against severe nerve injury-induced pathophysiological changes with improved neural gene expression and enhances functional recovery

The functional recovery following non-severing peripheral nerve injury (PNI) is often incomplete. Erythropoietin (EPO) is a pleiotropic hormone and it has been shown to protect peripheral nerves following mild and even moderate severity injuries. However, the effectiveness of EPO in severe PNI is largely unknown. In this study, we sought to investigate the neuroprotective effect of a new dose regimen of EPO in severe sciatic nerve crush injury (SSCI). Adult male mice (8 animals/group) were randomly assigned to sham (normal saline, 0.1 ml/mouse), SSCI (normal saline, 0.1 ml/mouse) and SSCI with EPO (5000 IU/kg) groups. SSCI was performed using calibrated forceps for 30 sec. EPO or normal saline was administered intraperitoneally immediately after the SSCI and at post-injury day1 and 2. The functional recovery after injury was assessed by sciatic function index (SFI), von Frey Test (VFT), and grip strength test. Mice were euthanized on day 7 and 21 and nerves at injury/peri-injury site were processed for gene (quantitative real-time PCR) and protein (immunohistochemistry) expression analysis. EPO significantly improved SFI, VFT, and hind limb paw grip strength from post-injury day 7. EPO demonstrated significant regulatory effects on mRNA expression of inflammatory (IL-1β and TNF-α), anti-inflammatory (IL-10), angiogenesis (VEGF and eNOS), and myelination (MBP) genes. The protein expression of IL-1β, F4/80, CD31, NF-κB p65, NF-H, MPZ, and DHE (redox-sensitive probe) was also significantly modulated by EPO treatment. In conclusion, the new dose regimen of EPO augments sciatic nerve functional recovery by mitigating inflammatory, anti-inflammatory, oxidative stress, angiogenesis, and myelination components of SSCI.

[Doping in elite and popular sport : What orthopedic and trauma surgeons should know]

The spectacular doping raid during the Nordic World Ski Championships in Seefeld in winter this year is not the first time that illegal performance enhancement by taking drugs is in the spotlight of public interest. Kicked off by the so-called Festina scandal of the 1998 Tour de France, the serial exposure of further doping offences continues up to the present day. Less well-known to the general public is the high prevalence of doping under hobby and amateur athletes. Physicians are confronted by this group of patients in the practice much more frequently than by elite athletes, who are mostly treated in closed medical networks. The aim of the article is to provide an overview of the medical aspects including the most frequent substance classes and the current legal foundations of the anti-doping movement. Furthermore, the official definition of doping and the structure of the anti-doping agencies are presented.

Environmental Risk Factors for Stroke and Cardiovascular Disease

Besides the classical individual stroke risk factors a new class has appeared, the environmental risk factors. After a review of the evidences demonstrating that air pollution is a potent risk factor (Part 1), we propose an update of other physical, chemical, and biological factors, now considered as risk factors (Part 2). One of the challenges is to precise their specific roles as they can be combined in their noxious impacts (traffic air pollution + noise + weather + infections). This knowledge has practical consequences; From now on, medical advices cannot be limited to individual recommendations but must also deal with environmental public health issues.

Strategy for erythroid differentiation in ex vivo cultures: Lentiviral genetic modification of human hematopoietic stem cells with erythropoietin gene

If cultured in appropriate conditions, such as supplementing culture media with costly cytokines and growth factors, hematopoietic stem/progenitor cells (HSPCs) from different origins have shown to be an adequate source of erythroid cells. This requirement turns erythroid cells production into a complicated process to be scaled-up for future applications. The aim of our work was to genetically modify HSPCs with human erythropoietin (hEPO) sequence by lentiviral transgenesis in order for cells to secrete the hormone into the culture medium. Initially, we evaluated erythroid differentiation in colony forming units (CFU) assays and further analyzed cell expansion and erythroid differentiation throughout time in suspension cultures by flow cytometry and May-Grünwald-Giemsa staining. Additionally, we studied hEPO production and its isoforms profile. The different assessment approaches demonstrated erythroid differentiation, which was attributed to the hEPO secreted by the HSPCs. Our data demonstrate that it is possible to develop culture systems in which recombinant HSPCs are self-suppliers of hEPO. This feature makes our strategy attractive to be applied in biotechnological production processes of erythroid cells that are currently under development.

Doping in sport and exercise: anabolic, ergogenic, health and clinical issues

The use of doping agents is evident within competitive sport in senior and junior age groups, where they are taken by non-elite as well as elite participants. They are also taken in non-sporting contexts by individuals seeking to ‘improve’ their physique through an increase in muscle and/or decrease in fat mass. While attaining accurate data on the prevalence of their use has limitations, studies suggest the illicit use of doping agents by athletes and non-athletes may be 1–5% in the population and greater than 50% in some groups; with the prevalence being higher in males. There is conclusive evidence that some doping agents are anabolic and ergogenic. There is also evidence that the use of doping agents such as anabolic androgenic steroids, growth hormone and other anabolic agents, erythropoietin and stimulants conveys considerable health risks that include, but are not limited to: cardiovascular disease, diabetes, cancer, mental health issues, virilisation in females and the suppression of naturally produced androgens in males. This review will outline the anabolic, ergogenic and health impacts of selected doping agents and methods that may be used in both the sporting and physique development contexts. It also provides a brief tabulated overview of the history of doping and how doping agents may impact upon the analyses of clinical samples.

Erythropoietin: a hormone with multiple functions

Erythropoietin (EPO), the main hemopoietic hormone synthesized by the kidney as well as by the liver in fetal life, is implicated in mammalian erythropoiesis. Production and secretion of EPO and the expression of its receptor (EPO-R) are regulated by tissue oxygenation. EPO and EPO-R, expressed in several tissues, exert pleiotropic activities and have different effects on nonhemopoietic cells. EPO is a cytokine with antiapoptotic activity and plays a potential neuroprotective and cardioprotective role against ischemia. EPO is also involved in angiogenesis, neurogenesis, and the immune response. EPO can prevent metabolic alterations, neuronal and vascular degeneration, and inflammatory cell activation. Consequently, EPO may be of therapeutic use for a variety of disorders. Many tumors express EPO and/or EPO-R, but the action of EPO on tumor cells remains controversial. It has been suggested that EPO promotes the proliferation and survival of cancer cells expressing EPO-R. On the other hand, other reports have concluded that EPO-R plays no role in tumor progression. This review provides a detailed insight into the nonhemopoietic role of EPO and its mechanism(s) of action which may lead to a better understanding of its potential therapeutic value in diverse clinical settings.

Erythropoietin and analogs

Erythropoietin (EPO), a glycoprotein hormone, stimulates the growth of red blood cells and as a consequence it increases tissue oxygenation. This performance enhancing effect is responsible for the ban of erythropioetin in sports since 1990. Especially its recombinant synthesis led to the abuse of this hormone, predominatly in endurance sports. The analytical differentiation of endogenously produced erythropoietin from its recombinant counterpart by using isoelectric focusing and double blotting is a milestone in the detection of doping with recombinant erythropoietin. However, various analogous of the initial recombinant products, not always easily detectable by the standard IEF-method, necessitate the development of analytical alternatives for the detection of EPO doping. The following chapter summarizes its mode of action, the various forms of recombinant erythropoietin, the main analytical procedures and strategies for the detection of EPO doping as well as a typical case report.

Detection of testosterone administration based on the carbon isotope ratio profiling of endogenous steroids: international reference populations of professional soccer players

BACKGROUND AND OBJECTIVES

The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined.

METHODS

Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS).

RESULTS

Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases.

CONCLUSIONS

The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids.

Effect of intermittent hypoxia on hematological parameters after recombinant human erythropoietin administration

Recent publications reflect the anti-doping authorities' concern about the use of altitude simulator systems as violating the spirit of sport criterion (Levine 2006; Loland and Murray 2007; Spriggs 2005). The aim of our study was to determine whether intermittent hypoxic treatments could modify the hemoglobin, hematocrit, reticulocytes, and erythropoietic stimulation index (OFF-Hr Score) values after administration of rHuEPO-alpha. Although these hematological parameters are of secondary nature some international sport federations currently exclude athletes who show aberrant values of these parameters from competition. Ten young male Wistar rats were treated, three times a week for 2 weeks, with 500 IU of rHuEPO-alpha. After the treatment, the animals were randomly divided into two groups: normoxic and hypoxic. The normoxic group was maintained at 21% O(2) 24 h a day for 23 days. The hypoxic group was maintained 12 h at 21% O(2) and 12 h at 12% O(2) (~4,000 m) the same time period. After the rHuEPO-alpha treatment, the hypoxic group of animals had a faster recovery rate in the reticulocyte count, elevated concentrations of hemoglobin and hematocrit and a significant increase in the endogenous EPO levels when compared with the normoxic group of animals. These changes led to significant modifications in the OFF-Hr Score between the hypoxic and normoxic animals. Intermittent hypoxic treatments after rHuEPO administration can significantly modify the main hematological parameters tested by the anti-doping authorities. Our results in an animal model suggest checking the described phenomena in humans in order to reach major conclusions.

Drug-induced hematologic syndromes

Objective. Drugs can induce almost the entire spectrum of hematologic disorders, affecting white cells, red cells, platelets, and the coagulation system. This paper aims to emphasize the broad range of drug-induced hematological syndromes and to highlight some of the newer drugs and syndromes. Methods. Medline literature on drug-induced hematologic syndromes was reviewed. Most reports and reviews focus on individual drugs or cytopenias. Results. Drug-induced syndromes include hemolytic anemias, methemoglobinemia, red cell aplasia, sideroblastic anemia, megaloblastic anemia, polycythemia, aplastic anemia, leukocytosis, neutropenia, eosinophilia, immune thrombocytopenia, microangiopathic syndromes, hypercoagulability, hypoprothrombinemia, circulating anticoagulants, myelodysplasia, and acute leukemia. Some of the classic drugs known to cause hematologic abnormalities have been replaced by newer drugs, including biologics, accompanied by their own syndromes and unintended side effects. Conclusions. Drugs can induce toxicities spanning many hematologic syndromes, mediated by a variety of mechanisms. Physicians need to be alert to the potential for iatrogenic drug-induced hematologic complications.

Philosophy on steroids: why the anti-doping position could use a little enhancement

There is currently much concern over the use of pharmaceuticals and other biomedical techniques to enhance athletic performance--a practice we might refer to as doping. Many justifications of anti-doping efforts claim that doping involves a serious moral transgression. In this article, I review a number of arguments in support of that claim, but show that they are not conclusive, suggesting that we do not have good reasons for thinking that doping is wrong.

Testing for recombinant erythropoietin

Erythropoietin (Epo) is a glycoprotein hormone that promotes the production of red blood cells. Recombinant human Epo (rhEpo) is illicitly used to improve performance in endurance sports. Doping in sports is discouraged by the screening of athletes for rhEpo. Both direct tests (indicating the presence of exogeneous Epo isoforms) and indirect tests (indicating hematological changes induced by exogenous Epo administration) can be used for Epo detection. At present, the test adopted by the World Anti Doping Agency is based on a combination of isoelectric focusing and double immunoblotting, and distinguishes between endogenous and rhEpo. However, the adopted monoclonal anti-Epo antibodies are not monospecific. Therefore, the test can occasionally lead to the false-positive detection of rhEpo (epoetin-beta) in post-exercise, protein-rich urine, or in case of contamination of the sample with microorganisms. An improved preanalytical care may counteract a lot of these problems. Adaptation of the criteria may be helpful to further refine direct Epo testing. Indirect tests have the disadvantage that they require blood instead of urine samples, but they can be applied to detect a broader range of performance improving techniques which are illicitly used in sports.

The use of medication and nutritional supplements during FIFA World Cups 2002 and 2006

Objective:

To examine medication use in male top-level football players prior to and during international tournaments.

Design:

Prospective survey.

Material:

2944 team physicians’ reports on players’ medication intake.

Methods:

Each team physician was asked to document all medication and nutritional supplements taken in the 72 h prior to each match.

Results:

A total of 10 384 substances were reported (1.8 substances/player/match); 4450 (42.9%) of these were medicinal and 5934 (57.1%) nutritional supplements. The medications prescribed most frequently were non-steroidal anti-inflammatory agents (n = 2092; 20.1%); more than half of the players took these at least once during a tournament and more than 10% prior to every match (156 out of 1472). β-2-Agonists were reported for 1.4% (n = 20) and inhaled corticosteroids for 1.6% (n = 23) of participating players. Injected corticosteroids were reported for 73 players.

Conclusions:

The high intake of medication in international football – especially of non-steroidal anti-inflammatory drugs – is alarming and should be addressed. The results raise questions as to whether the medication was taken solely for therapeutic reasons. In view of the potential side effects, more restrictive recommendations for sport need to be developed.

Erythropoietin and other blood-boosting methods

Dating back to the earliest Olympics, athletes have been searching for a performance edge. Recombinant human erythropoietin was made commercially available in 1987 to treat various diseases associated with anemia. Within a few years, elite endurance athletes capitalized on its potential as an undetectable performance-enhancing agent. Although antidoping agencies have developed a test to detect its use, there are pitfalls. More importantly, athletes continue to add more sophisticated doping practices to their armamentarium, challenging regulatory agencies, putting their health at great risk, and tainting the spirit of fair competition.

Blood transfusions in athletes. Old dogmas, new tricks

Blood doping consists of any illicit means used to increase and optimize oxygen delivery to the muscles and includes blood transfusions, administration of erythropoiesis-stimulating substances, blood substitutes, natural or artificial altitude facilities, and innovative gene therapies. The use of blood transfusion, an extremely straightforward, practical and effective means of increasing an athlete's red blood-cell supply in advance of competition, became rather popular in the 1970s, but it has suddenly declined following the widespread use of recombinant human erythropoietin among elite endurance athletes. Most recently, following implementation of reliable tests to screen for erythropoiesis-stimulating substances, blood transfusions have made a strong resurgence, as attested by several positive doping tests. Doping by blood transfusion can be classified as homologous, where the blood is infused into someone other than the donor, and autologous, where the blood donor and transfusion recipient are the same. The former case produces more clinically relevant side effects, but is easily detectable using current antidoping protocols based on erythrocyte phenotyping by flow cytometry and, eventually, erythrocyte genotyping by DNA testing. Since the donor and recipient blood are identical in autologous blood doping, this is less risky, though much more challenging to detect. Indirect strategies, relying on significant deviations from individual hematological profiles following autologous blood donation and reinfusion, are currently being investigated. For the time being, the storage of athletes' blood samples to allow testing and sanctioning of guilty athletes once a definitive test has been introduced may represent a reliable deterrent policy.