Doping Control Analysis of Bovine Hemoglobin-Based Oxygen Therapeutics in Human Plasma by LC−Electrospray Ionization-MS/MS

Whispers in the Blood: Leveraging MicroRNAs for Unveiling Autologous Blood Doping in Athletes

The prevalence of autologous blood transfusions (ABTs) presents a formidable challenge in maintaining fair competition in sports, as it significantly enhances hemoglobin mass and oxygen capacity. In recognizing ABT as a prohibited form of doping, the World Anti-Doping Agency (WADA) mandates stringent detection methodologies. While current methods effectively identify homologous erythrocyte transfusions, a critical gap persists in detecting autologous transfusions. The gold standard practice of longitudinally monitoring hematological markers exhibits promise but is encumbered by limitations. Despite its potential, instances of blood doping often go undetected due to the absence of definitive verification processes. Moreover, some cases remain unpenalized due to conservative athlete-sanctioning approaches. This gap underscores the imperative need for a more reliable and comprehensive detection method capable of unequivocally differentiating autologous transfusions, addressing the challenges faced in accurately identifying such prohibited practices. The development of an advanced detection methodology is crucial to uphold the integrity of anti-doping measures, effectively identifying and penalizing instances of autologous blood transfusion. This, in turn, safeguards the fairness and equality essential to competitive sports. Our review tackles this critical gap by harnessing the potential of microRNAs in ABT doping detection. We aim to summarize alterations in the total microRNA profiles of erythrocyte concentrates during storage and explore the viability of observing these changes post-transfusion. This innovative approach opens avenues for anti-doping technologies and commercialization, positioning it as a cornerstone in the ongoing fight against doping in sports and beyond. The significance of developing a robust detection method cannot be overstated, as it ensures the credibility of anti-doping efforts and promotes a level playing field for all athletes.

Detection of extracellular hemoglobin from Arenicola marina in doping control serum samples by means of liquid chromatography and high-resolution tandem mass spectrometry

The manipulation of blood and blood components in sports is prohibited at all times, and besides blood transfusions, also hemoglobin-based oxygen carriers (HBOCs) can be employed to artificially improve the oxygen transport capacity of the blood. But while most drug candidates based on stabilized hemoglobin (Hb) were found to be characterized by serious side effects, the natural giant extracellular Hb from the marine invertebrate Arenicola marina (lugworm) could be another candidate for transfusion medicine and cheating athletes, as it was found to be well tolerated in preclinical animal studies. Within this research project, lugworm Hb was implemented into the existing doping control detection method for bovine HBOCs based on ultrafiltration, tryptic digestion, and liquid chromatography coupled with high-resolution tandem mass spectrometry (LC-HRMS/MS). For the mass spectrometric identification of lugworm Hb, two precursor-product ion pairs for a total of four tryptic peptides originating from subunits hbA2 (T6 ), hbB1 (T3 and T6 ), and the linker chain (T16 ) were employed. The modified approach was comprehensively characterized and found to allow for the specific and sensitive detection of lugworm Hb down to concentrations of 10 μg/mL from 50 μL of serum/plasma. Therefore, it can serve as confirmation procedure for lugworm Hb following visual or electrophoretic screening. Moreover, a proof-of-concept rat administration study was conducted, and the observed detection windows of at least 4 (dose: 200 mg/kg) and 8 h (dose: 600 mg/kg) suggest that the approach can be readily employed to efficiently test in-competition doping control samples for the presence of the drug candidate.

Novel biomarker pipeline to probe the oxidation sites and oxidation degrees of hemoglobin in bovine erythrocytes exposed to oxidative stress

Research on biomarkers for protein oxidation might give insight into the mechanistic mode of oxidative stress. In the work present here, a novel pipeline was established to probe the oxidation mechanism of bovine hemoglobin (Hb) with its oxidation products serving as the biomarkers. Reactive oxygen species generated by irradiation were used to mimic oxidative stress conditions to oxidize Hb in bovine erythrocytes. After Hb extraction and digestion, oxidized peptides in the tryptic fragments were assigned by comparison with the extracted ion chromatography spectra of native peptide from the control sample. Subsequent tandem mass spectrometry analysis of these peptides proved that oxidation was limited to partially exposed amino acid residues (α-Phe36 , β-Met1 , β-Trp14 , for instance) in Hb. Quantitation analysis on these oxidized peptides showed that oxidation degrees of target sites had positive correlations with the extended oxidation dose and the oxidation processes were also controlled by residues types. Compared with the conventional protein carbonyl assay, the identified oxidized products were feasibility biomarkers for Hb oxidation, indicating that the proposed biomarker pipeline was suitable to provide specific and valid information for protein oxidation. Copyright © 2015 John Wiley & Sons, Ltd.

Analytical progresses of the International Olympic Committee and World Anti-Doping Agency Olympic laboratories

The Summer Olympic Games constitute the biggest concentration of human sports and activities in a particular place and time since 776 BCE, when the written history of the Olympic Games in Olympia began. Summer and Winter Olympic anti-doping laboratories, accredited by the International Olympic Committee in the past and the World Anti-Doping Agency in the present times, acquire worldwide interest to apply all new analytical advancements in the fight against doping in sports, hoping that this major human event will not become dirty by association with this negative phenomenon. This article summarizes the new analytical progresses, technologies and knowledge used by the Olympic laboratories, which for the vast majority of them are, eventually, incorporated into routine anti-doping analysis.

Mass spectrometry-based analysis of IGF-1 and hGH

Mass spectrometric approaches have been used to determine various peptide hormones in sports drug testing. While insulin-like growth factor-1 (IGF-1) and its synthetic analogs are qualitatively and/or quantitatively measured by liquid chromatography-tandem mass spectrometry after immunoaffinity purification, methods of uncovering doping rule violations with illegal applications of human growth hormone (hGH) have not yet been established using mass spectrometry-based assays. However, substantial information on the heterogeneity of hGH, splice variants and post-translational modifications with respective locations as elucidated by mass spectrometry are of utmost importance for improving currently employed immunological procedures.

Medicine and science in the fight against doping in sport

The fight against doping in sports commenced as a result of the death of a Danish cyclist during the Rome Olympic Games in 1960. The International Olympic Committee (IOC) established a Medical Commission (IOC-MC) which had the task of designing a strategy to combat the misuse of drugs in Olympic Sport. Some International Sport Federations (IF) and National Sports Federations followed suit, but progress was modest until the world's best male sprinter was found doped with anabolic steroids at the Olympic Games in Seoul in 1988. Further progress was made following the cessation of the cold war in 1989 and in 1999 public authorities around the world joined the Olympic Movement in a unique partnership by creating WADA--the 'World Anti-Doping Agency'. The troubled history of the anti-doping fight from the 1960s until today is reviewed. In particular, the development of detection methods for an ever increasing number of drugs that can be used to dope is described, as are the measures that have been taken to protect the health of the athletes, including those who may need banned substances for medical reasons.

History of mass spectrometry at the Olympic Games

Mass spectrometry has played a decisive role in doping analysis and doping control in human sport for almost 40 years. The standard of qualitative and quantitative determinations in body fluids has always attracted maximum attention from scientists. With its unique sensitivity and selectivity properties, mass spectrometry provides state-of-the-art technology in analytical chemistry. Both anti-doping organizations and the athletes concerned expect the utmost endeavours to prevent false-positive and false-negative results of the analytical evidence. The Olympic Games play an important role in international sport today and are milestones for technical development in doping analysis. This review of the part played by mass spectrometry in doping control from Munich 1972 to Beijing 2008 Olympics gives an overview of how doping analysis has developed and where we are today. In recognizing the achievements made towards effective doping control, it is of the utmost importance to applaud the joint endeavours of the World Anti-Doping Agency, the International Olympic Committee, the international federations and national anti-doping agencies to combat doping. Advances against the misuse of prohibited substances and methods, which are performance-enhancing, dangerous to health and violate the spirit of sport, can be achieved only if all the stakeholders work together.

Mass spectrometric determination of insulins and their degradation products in sports drug testing

Insulins' anabolic and anti-catabolic properties have supposedly led to its misuse in sport. Hence, doping control assays were developed to allow the unequivocal identification of synthetic insulin analogs and metabolic products derived from human insulin and its artificial counterparts in urine and plasma specimens. Analyses were based on immunoaffinity purification and subsequent characterization of target analytes by top-down sequencing-based approaches, which were conducted with hybrid tandem mass spectrometers that consisted of either quadrupole-linear ion trap or linear ion trap-orbitrap analyzers. Diagnostic product ions and analytical strategies are presented and discussed in light of the need to unambiguously identify misused drugs in urine and plasma specimens for doping control.

Current role of LC–MS(/MS) in doping control

Liquid chromatography-(tandem) mass spectrometry (LC-MS/MS) has revolutionized the detection assays used in doping control analysis over the last decade. New methods have enabled the determination of drugs that were formerly difficult to detect or undetectable at preceding sample concentrations, and complex and/or time-consuming procedures based on alternative chromatographic-mass spectrometric or immunochemical principles have been replaced by faster, more comprehensive and robust assays. A critical overview of the contributions of LC-MS(/MS) to sports drug testing is provided, including recent developments regarding low and high molecular weight drugs.

Mass spectrometry in sports drug testing: Structure characterization and analytical assays

Owing to the sensitive, selective, and unambiguous nature of mass spectrometric analyses, chromatographic techniques interfaced to various kinds of mass spectrometers have become the most frequently employed strategy in the fight against doping. To obtain utmost confidence in analytical assays, mass spectrometric characterization of target analytes and typical dissociation pathways have been utilized as basis for the development of reliable and robust screening as well as confirmation procedures. Methods for qualitative and/or quantitative determinations of prohibited low and high molecular weight drugs have been established in doping control laboratories preferably employing gas or liquid chromatography combined with electron, chemical, or atmospheric pressure ionization followed by analyses using quadrupole, ion trap, linear ion trap, or hyphenated techniques. The versatility of modern mass spectrometers enable specific as well as comprehensive measurements allowing sports drug testing laboratories to determine the misuse of therapeutics such as anabolic-androgenic steroids, stimulants, masking agents or so-called designer drugs in athletes' blood or urine specimens, and a selection of recent developments is summarized in this review.

Recommended criteria for the mass spectrometric identification of target peptides and proteins (<8 kDa) in sports drug testing

Mass spectrometry has become an invaluable tool for the identification of prohibited peptide hormones and proteins in doping control analysis. Regulatory authorities have established criteria for identifying banned drugs in doping control specimens, but these criteria do not address the specific issues for high molecular weight protein drugs such as molecular weight determination of multiply charged molecules, analysis of chemically or enzymatically derived degradation products, identification of amino acid sequence tags, etc. Technical considerations such as sample preparation methods (e.g. immunoaffinity purification), resulting analytes (e.g. intact compounds vs. chemically or enzymatically derived peptides), ionization modes, analyzer resolution, and the information provided by respective techniques are discussed in light of sports drug testing requirements using typical application examples.

Electrophoretic, size-exclusion high-performance liquid chromatography and liquid chromatography-electrospray ionization ion trap mass spectrometric detection of hemoglobin-based oxygen carriers

Hemoglobin-based oxygen carriers (HBOCs) are blood substitutes based on hemoglobin of either bovine or human origin and they can potentially be misused in elite sports to improve endurance performance. Recently, three methods have been proposed in doping control analysis to allow HBOCs screening and identification by application of electrophoresis, size-exclusion chromatography coupled with HPLC and LC coupled with tandem mass spectrometry (LC/MSMS). In view of the Athens 2004 Olympic Games, modifications were introduced in order to increase the specificity of these methods. The sample preparation protocols of the electrophoretic and SEC-HPLC methods were modified with the introduction of sequential ultra filtration steps to remove all heme containing material below 100 kDa, thus leaving only HBOCs material for analysis. Furthermore, a modification of the LC/MSMS methodology was introduced to allow full scan MS-MS spectra of peptide segments arising from the tryptic digestion of bovine HBOCs. These relatively simple methodological modifications have major impact, as far as time and cost effectiveness is concerned in doping control procedures, because they provide a useful tool in order to identify which suspect samples from the initial visual screening are due to hemolysis and exclude them from further analysis.

The Pharmacokinetics of Hemoglobin-Based Oxygen Carrier Hemoglobin Glutamer-200 Bovine in the Horse

Hemoglobin-glutamer-200 (HBOC-200) is a hemoglobin (Hb)-based oxygen carrier (HBOC) comprising glutaraldehyde-polymerized bovine Hb. In this study, we sought to determine the pharmacokinetics of this first generation HBOC after IV infusion of 32.5 g of HBOC-200 solution in horses. Quantification of HBOC-200 in equine plasma and urine was performed using a method recently developed by our laboratory. The elimination from plasma was based on size distribution of the bovine Hb polymer. The decline of plasma concentration-time curve of HBOC-200 was described by a noninterchanging 2-compartmental model. The median elimination half-lives of the small and large aggregates were 1.3 and 12.0 h, respectively. Of the HBOC-200 infused, 47.0% was eliminated as the smaller molecular weight and 53% as the larger molecular weight polymers. The area under the plasma concentration-time curve was 5143.1 microg.h(-1).mL(-1). The volumes of distribution of the small and large aggregates were 86.9 and 63.9 mL/kg and the clearances were 42.1 and 3.8 mL.kg(-1).h(-1), respectively. In conclusion, elimination of first generation HBOCs was shown to be more complex than previously assumed because of the heterogeneous nature of these solutions. Mammalian species dispose of Hb using similar mechanisms, and there is no unique metabolic process in the horse that would not allow a logical extension of the general interpretation of this study.

N-Terminal Adducts of Bovine Hemoglobin with Glutaraldehyde in a Hemoglobin-Based Oxygen Carrier

Hemoglobin-based oxygen carriers (HBOCs) are being developed for the medical field, but because they could increase an athlete's performance, they are misapplied for doping purposes. We previously presented a screening method to detect Oxyglobin (Biopure Corp.) and PolyHeme (Northfield Laboratories Inc.) in serum samples using total acid hydrolysis followed by electrospray mass spectrometry analyses. An alternative mass spectrometric method involving enzymatic hydrolysis is here presented. Digestion of Oxyglobin by endoproteinase Glu-C and LC/MS analyses of the mixture allowed the detection of unique peptidic fragments in comparison with a bovine hemoglobin digest. Tandem mass spectrometry experiments of these peptide ions were performed, and two specific species were actually identified as the N-terminal enzymatic fragment of the beta chain carrying two different modifications. Sequential MS3 experiments using an ion trap mass spectrometer permitted us to locate the chemical modification by the glutaraldehyde on the NH2-terminal group and to propose a structure for the modified peptides. In another set of experiments, screening of these two diagnostic ions into Oxyglobin-spiked serums using precursor ion scan mode in a triple quadrupole instrument allowed the detection of this HBOC with a detection limit of 2 g L(-1).

Simple Identification of A Cross-Linked Hemoglobin by Tandem Mass Spectrometry in Human Serum

Hemoglobin-based oxygen therapeutics are prepared by reaction of hemoglobin with cross-linking molecules and are utilized as blood substitutes. They can be used as doping agents to increase the oxygen-carrying capacity of hemoglobin. We have compared a glutaraldehyde-polymerized bovine hemoglobin (Oxyglobin, Biopure Corp.) with natural bovine hemoglobin by mass spectrometry in order to detect specific fragment ions of the cross-linked protein for further potential applications in doping control of human blood samples. HCl acid (6 N) hydrolysis was performed in parallel on both proteins. Hydrolysates were then analyzed by direct infusion electrospray mass spectrometry (ESIMS) using a triple quadrupole mass spectrometer. Confirmation and precision were obtained by LC-ESIMS(n) experiments performed on an ion trap mass spectrometer. Chromatographic and mass spectrometry data allowed detection of two potential Oxyglobin-specific ions--m/z 299 and 399--that were shown to lose a 159 u neutral fragment under collision-induced dissociation conditions. Thus, monitoring of constant neutral loss of 159 u on acid hydrolysates of human serum samples spiked with different amounts of Oxyglobin has proved to be an efficient screening method to specifically detect and identify Oxyglobin. LC-MS of the spiked serum sample hydrolysates enabled detection of Oxyglobin at a detection limit of 4 g x L(-1).

Confirmation and quantification of hemoglobin-based oxygen carriers in equine and human plasma by hyphenated liquid chromatography tandem mass spectrometry

Oxyglobin (OXY) and Hemopure (HMP) are produced from bovine hemoglobin (Hb) and were developed for the treatment of anemia in animal and human patients, respectively. Hemolink (HML) is a blood substitute of human Hb origin under development. The ability of these agents to carry oxygen in circulating blood and their promise to improve oxygen delivery to tissues supports the potential for their abuse in equine and human athletes. To deter athletes from abuse of these agents, a method has been developed for the detection, confirmation and quantification of OXY, HMP, and HML in equine and human plasma. OXY, HMP, and HML were extracted from equine or human plasma by solid-phase extraction using Bond Elut ENV cartridges and were digested by trypsin at 37 degrees C for 3 h. The tryptic digests were analyzed by LC-MS/MS, and tryptic peptides specific for bovine and human Hbs were targeted. OXY and HMP were detected, quantified, and confirmed using the y14 ion and b8 ion of the tryptic peptide from bovine Hb alpha chain residues 69-90, and HML was quantified using the tryptic peptide from human Hb alpha chain residues 63-91. The limit of detection for OXY in equine plasma and HML in human and equine plasma was 50 and 250 microg/mL for HMP in human and equine plasma. The limit of confirmation was 250 microg/mL for OXY in equine plasma, 500 microg/mL for HML in human and equine plasma, and 1000 microg/mL for HMP in human and equine plasma. The linear range for quantification was 50-5000 microg/mL for OXY in equine plasma and for HML in human and equine plasma, and 250-5000 microg/mL for HMP in human and equine plasma. The intraday and interday CV were less than 17% for quantification of OXY in equine plasma with external calibration. OXY was stable for more than 30 days at -20 and -70 degrees C. OXY was detected and quantified in equine plasma up to 24 h following administration of a very low dose of OXY (32.5 g in 2 x 125 mL per horse), and its presence in equine plasma was confirmed up to 12 h postadministration.

Unique Tryptic Peptides Specific for Bovine and Human Hemoglobin in the Detection and Confirmation of Hemoglobin-Based Oxygen Carriers

Hemoglobin-based oxygen carriers (HBOCs) of bovine hemoglobin (Hb) or human Hb origin were developed for replacement or augmentation of blood during transfusion and have the potential to increase oxygen-carrying capacity of circulating blood and thus improve tissue oxygen delivery. Due to their potential for increasing oxygen-carrying capacity of circulating blood, they are excellent candidates for abuse in human and equine athletes. To deter athletes from blood doping with HBOCs such as Hemopure and Oxyglobin (OXY), a method for detection, confirmation, quantification, and distinguishing of HBOCs from native hemoglobin in test samples is needed. The purpose of this study was to identify unique peptides specific for bovine Hb and human Hb that are useful in the detection and confirmation of HBOCs in test samples. The LC-MS chromatographic peak profiles of tryptic digests from OXY, bovine Hb, human Hb, and equine Hb were compared, and unique tryptic peptides specific for bovine Hb, human Hb, and equine Hb were identified. The peptides specific for bovine Hb and OXY are related to bovine Hb alpha chain residues 69-90 and beta chain residues 40-58. The peptides specific for human Hb are related to human Hb alpha chain residues 63-91 and beta chain residues 42-60 and 68-83. The amino acid sequences of these unique tryptic peptides were confirmed by their characteristic MS/MS spectra. MS/MS spectra, b-ion series and y-ion series, and LC retention time of the tryptic peptides are essential pieces of information for the unequivocal identification, detection, and confirmation of HBOCs. The results of this study provide useful and defensible data on identification, detection, and confirmation of HBOCs of bovine Hb or human Hb origin. In addition, in-ESI-source fragmentation of tryptic peptides was observed in this study. The fragmentation was undesired since it decreased intensities of the trypic peptide ions, but it was helpful to elucidating sequences of the tryptic peptides thanks to the fragment peptide ions produced from the fragmentation.