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1.
Biomed Chromatogr ; 34(6): e4821, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32150287

ABSTRACT

Polygoni multiflori Radix Praeparata (PMRP) is a traditional medicine used for nourishing essence and blood in China. However, it is unclear which PMRP compounds are responsible for its hematopoietic effect. In this study, spectrum-effect relationship was used to discovery potential hematopoietic compounds. The fingerprints of 20 PMRP batches were established by HPLC and the hematopoietic effect was determined using red blood cell, hemoglobin, hematocrit, and platelet indexes in aplastic anemia model mice. The spectrum-effect relationship between common peaks and hematopoietic efficacy values was established using gray relational analysis and partial least squares analysis. Spectrum-effect relationship results showed that peaks 21 (emodin-8-O-(6´-O-acetyl)-ß-D-glucoside), 15 (2, 3, 5, 4'-tetrahydroxystilbene-2-O-di-glucoside), 16 (cis-2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-D-glucoside), 11 (unknown), 20(unknown, 12 (epicatechin), 29 (carboxyl emodin), and 31 (emodin) in the fingerprints were closely related to the hematopoietic effect. This work successfully established the spectrum-effect relationship between PMRP hematopoietic effect and its fingerprints, which can be used to explain the material basis for the PMRP hematopoietic effect.


Subject(s)
Drugs, Chinese Herbal , Hematinics , Anemia, Aplastic , Animals , Cell Count , Chromatography, High Pressure Liquid , Disease Models, Animal , Drugs, Chinese Herbal/analysis , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Erythrocytes/drug effects , Hematinics/analysis , Hematinics/chemistry , Hematinics/pharmacology , Hematologic Tests , Hemoglobins/analysis , Male , Mice , Mice, Inbred ICR
2.
Br J Sports Med ; 48(10): 842-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24677025

ABSTRACT

Detection methods for erythropoiesis-stimulating agents in sport can be classified into direct and indirect approaches. Direct methods comprise electrophoretic techniques (isoelectric focusing (IEF-), sodium-dodecylsulfate (SDS-), sarcosyl (SAR-) polyacrylamide gel-electrophoreses (-PAGE)), ELISAs and mass spectrometric methods. The haematological module of the Athlete Biological Passport is currently the only applied indirect approach. Newer developments include a mass spectrometric test for peginesatide, sequential exoglycosidase digestion of ertythropoietin (EPO) combined with electrophoresis (SDS/SAR-PAGE), a dipstick method (MAIIA), and a study on the differences in sialic acid O-acetylation of tryptic EPO O-glycopeptides. The focus of this article is on direct detection methods.


Subject(s)
Doping in Sports/prevention & control , Hematinics/analysis , Performance-Enhancing Substances/analysis , Substance Abuse Detection/methods , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Humans , Isoelectric Focusing , Mass Spectrometry
3.
Drug Test Anal ; 14(8): 1377-1386, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35322582

ABSTRACT

The World Anti-Doping Agency (WADA) has recently implemented dried blood spots (DBSs) as a matrix for doping control. However, specifications regarding the analysis of the class of prohibited substances called erythropoietin (EPO) receptor agonists (ERAs) from DBSs are not yet described. The aim of this study was to find optimal conditions (sample volume and storage) to sensitively detect endogenous erythropoietin (hEPO) and prohibited ERAs from DBSs and compare detection limits to WADA-stipulated minimum required performance levels (MRPLs) for ERAs in serum/plasma samples. Venous whole blood was spotted onto Whatman 903 DBS cards with primarily 60 µl of blood, but various volumes from 20 to75 µl were tested. All samples were immunopurified with MAIIA EPO Purification Gel kit (EPGK) and analysed with sodium N-lauroylsarcosinate polyacrylamide gel electrophoresis (SAR-PAGE) and Western blot. Sixty-microliter DBSs allowed the detection of the four main ERAs (BRP, NESP, CERA and EPO-Fc) at concentrations close to WADA's MRPLs described for 500 µl of serum/plasma. Different storage temperatures, from -20°C to 37°C, were evaluated and did not affect ERA detection. A comparison of the detection of endogenous EPO from the different anti-doping matrices (urine, serum and DBSs produced from upper arm capillary blood) from five participants for 6 weeks was performed. Endogenous EPO extracted from DBSs showed intra-individual variations in male and female subjects, but less than in urine. Doping controls would benefit from the stability of ERAs on DBSs: It can be a complementary matrix for ERA analysis, particularly in the absence of EPO signals in urine.


Subject(s)
Doping in Sports , Hematinics , Receptors, Erythropoietin , Substance Abuse Detection , Dried Blood Spot Testing , Electrophoresis, Polyacrylamide Gel , Female , Hematinics/analysis , Humans , Male , Receptors, Erythropoietin/agonists , Substance Abuse Detection/methods
5.
Drug Test Anal ; 13(10): 1791-1796, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34342157

ABSTRACT

Erythropoietin receptor agonists (ERAs) are drugs acting on the early erythropoietic stages developed to treat anemia and other erythropoiesis disease and are prohibited by the World Anti-Doping Agency (WADA). As an alternative to ERAs, a new drug, belonging to the transforming growth factor-b inhibitors family, was recently developed to treat diseases linked to ineffective erythropoiesis. This drug, named as Luspatercept (Reblozyl®), is acting on the later stages of erythropoiesis to promote erythrocytes. This drug might be used by cheating athletes either independently or in combination with ERAs. Indeed, it was shown that Luspatercept and recombinant erythropoietin (rEPO) can act synergistically to increase red blood cells production, potentially allowing the use of lower doses for an efficient effect. Our aim was to find a way to combine the detection of ERAs and Luspatercept without impacting the sensitivity and specificity of ERAs detection from the current techniques implemented in antidoping laboratories and to reduce the time of analysis and total sample volume needed. Magnetic beads coated with antibodies were preferred for IP of samples for its potential multiplexing. Then, the following steps of the method were selected considering that SAR/SDS-PAGE are the electrophoretic methods authorized for initial testing procedure by WADA and that biotinylated primary antibodies used for the immunodetection results in the best sensitivity and specificity and is time saving. The method developed in this work for the combined detection of agents affecting erythropoiesis (AAEs) showed specificity, sensitivity, and robustness and is easily and quickly implementable to all antidoping laboratories.


Subject(s)
Activin Receptors, Type II/analysis , Doping in Sports/prevention & control , Hematinics/analysis , Immunoglobulin Fc Fragments/analysis , Recombinant Fusion Proteins/analysis , Substance Abuse Detection/methods , Electrophoresis, Polyacrylamide Gel , Erythropoiesis/drug effects , Humans , Sensitivity and Specificity
6.
J Pharm Sci ; 108(6): 2162-2172, 2019 06.
Article in English | MEDLINE | ID: mdl-30684541

ABSTRACT

Excessive fluid intake, that is, hyperhydration, may be adopted by athletes as a masking method during antidoping sample collection to influence the excretion patterns of doping agents and, therefore, manipulate their detection. The aim of this exploratory study was to assess the hyperhydration effect on the detection sensitivity of recombinant human erythropoietin (rHuEPO) by sodium N-lauroyl sarcosinate ("sarkosyl") polyacrylamide gel electrophoresis analysis. The influence of hyperhydration on the serum and urinary pharmacokinetic (PK) profiles of rHuEPO was also investigated. Seven healthy physically active nonsmoking Caucasian males participated in a 31-day clinical study comprising a baseline (days 0, 1-3, and 8-10) and a drug phase (days 15-17, 22-24, and 29-31). Epoetin beta was administered subcutaneously at a single dose of 3000 IU on days 15, 22, and 29. Hyperhydration was applied in the morning on 3 consecutive days (days 1-3, 8-10, 22-24, and 29-31), that is, 0, 24, and 48 h after first fluid ingestion. Water and a commercial sports drink were used as hyperhydration agents (20 mL/kg body weight). Serum and urinary concentration-time profiles were best described by a one-compartment PK model with zero-order absorption. Delayed absorption was observed after hyperhydration and, therefore, lag time was introduced in the PK model. Results showed no significant difference (p > 0.05) on serum or urinary erythropoietin concentrations under hyperhydration conditions. A trend for decreasing volume of distribution and increasing clearance after hyperhydration was observed, mainly after sports drink consumption. However, no significant differences (p > 0.05) due to hyperhydration for any of the serum PK parameters calculated by noncompartmental PK analysis were observed. Renal excretion of endogenous erythropoietin and rHuEPO, as reflected on the urinary cumulative amount, was increased approximately twice after hyperhydration and this supports the nonsignificant difference on the urinary concentrations. Analysis of serum and urine samples was able to detect rHuEPO up to 72 h after drug administration. The detection window of rHuEPO remained unaffected after water or sports drink ingestion. Hyperhydration had no effect on the detection sensitivity of EPO either in serum or urine samples.


Subject(s)
Doping in Sports/prevention & control , Electrophoresis, Polyacrylamide Gel/methods , Erythropoietin/analysis , Hematinics/analysis , Organism Hydration Status/physiology , Acrylic Resins/chemistry , Adult , Erythropoietin/administration & dosage , Erythropoietin/pharmacokinetics , Feasibility Studies , Hematinics/administration & dosage , Hematinics/pharmacokinetics , Humans , Injections, Subcutaneous , Male , Models, Biological , Recombinant Proteins/administration & dosage , Recombinant Proteins/analysis , Recombinant Proteins/pharmacokinetics , Renal Elimination/physiology , Reproducibility of Results , Sarcosine/analogs & derivatives , Sarcosine/chemistry , Sensitivity and Specificity
7.
Pak J Pharm Sci ; 21(4): 396-9, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18930861

ABSTRACT

The iron content of ferrous sulphate syrup and tablet, ferroglobin, and Fefol were determined by both titration with cerium (Cerimetric method) proposed by united state pharmacopeias and flame atomic absorption spectrometry (FAAS). In FAAS both external calibration and standard addition method were used to evaluate the matrix effects. In the determination of iron content of ferrous sulphate tablet and syrup FAAS using external standard give approximately the same results as cerimetric methods of analysis. But in the case of ferroglobin syrup and Fefol capsule the external calibration results had large deviation from cerimetric method of analysis. So flame atomic absorption spectrometric involving standard addition is proposed for the analysis of iron content of these pharmaceutical products. The coefficient of variation for the FAAS determinations were in the range of 0.73-5.85 in one day and 2.39-7.51 between different days. Statistical evaluation showed good correlation between two methods.


Subject(s)
Cerium/chemistry , Ferrous Compounds/analysis , Hematinics/analysis , Spectrophotometry, Atomic , Technology, Pharmaceutical/methods , Titrimetry , Calibration , Capsules , Excipients/chemistry , Pharmaceutical Solutions , Spectrophotometry, Atomic/standards , Tablets , Technology, Pharmaceutical/standards , Titrimetry/standards
8.
PDA J Pharm Sci Technol ; 61(6): 423-32, 2007.
Article in English | MEDLINE | ID: mdl-18410043

ABSTRACT

During the period of 1998 to 2002, there was an increase in the incidence of antibody-positive pure red cell aplasia (PRCA) in patients receiving subcutaneous administration of EPREX (epoetinum alfa). As part of the investigation of this event, the aqueous formulation containing polysorbate 80, introduced in 1998, facilitated the leaching of small-molecule, aromatic compounds from the uncoated rubber syringe stoppers. The leachables were identified using Liquid Chromatography-Mass Spectroscopy, Electrospray Ionisation-MS/MS, Dithiothreitol reduction, and Hydrogen/Deuterium exchange. The major leachable was identified as a dialkylphenol disulfide, and the majority of the remaining peaks were identified as structural variants containing different numbers of sulfur atoms in the sulfide bridge. In this report, we describe the strategies and experimental designs that were used to overcome the analytical challenges and that led to successful structural identification of the leachables in EPREX pre-filled syringes with uncoated syringe stoppers.


Subject(s)
Erythropoietin/adverse effects , Erythropoietin/analysis , Hematinics/adverse effects , Hematinics/analysis , Red-Cell Aplasia, Pure/chemically induced , Chemistry, Pharmaceutical , Chromatography, High Pressure Liquid , Drug Contamination , Drug Packaging , Epoetin Alfa , Erythropoietin/radiation effects , Gas Chromatography-Mass Spectrometry , Hematinics/radiation effects , Plastics , Recombinant Proteins , Syringes , Ultraviolet Rays
9.
Am J Sports Med ; 34(10): 1690-8, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16923823

ABSTRACT

Drug testing is now ubiquitous in sport, and it often falls to the team physician to perform a variety of roles including interpreting test results, designing drug-testing programs, acting as medical review officer, and providing therapeutic use exemptions, education, and counseling. Proper understanding of current testing methods for drugs such as anabolic-androgenic steroids, erythropoietin, and growth hormone is essential if the team physician is going to assume these positions. This article outlines the basics of athletic drug testing from the collection process through the interpretation of results to assist the team physician in this field.


Subject(s)
Doping in Sports/prevention & control , Substance Abuse Detection/methods , Darbepoetin alfa , Erythropoietin/analogs & derivatives , Erythropoietin/analysis , Guideline Adherence , Guidelines as Topic/standards , Hematinics/analysis , Human Growth Hormone/analysis , Humans , Sports Medicine , Steroids/analysis
10.
J Ethnopharmacol ; 182: 129-36, 2016 Apr 22.
Article in English | MEDLINE | ID: mdl-26911525

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Colla Corii Asini is a widely used traditional Chinese medicine to treat anemia with a long history due to its stimulating effect in hematopoiesis, but the components contributing to this effect are still unknown. In this study, we aimed to establish a methodology to isolate the bioactive components and provide pharmacological basis for its usage in treating anemia. METHODS: 5-FU and γ-ray radiation induced anemic mice models were generated by treating with 5-FU at 150mg/kg body weight and γ-rays by a 4MV linear accelerator by total body irradiation using female ICR mice respectively. Oral administration of fraction A was performed by gastric lavage at 1g/kg and 2g/kg body weight for 12 days and 25 days and peripheral blood sample was collected from ocular sinus red blood cell (RBC) and white blood cell (WBC) counts every 3 days and 5 days for 5-FU and radiation induced models, respectively. Next, fraction A was separated to A1 and A2 using cation exchange chromatography (IEC) based on ionic strength. Fraction A1 was further separated using reverse phase chromatography (RPC) based on the hydrophobicity first with 0-10% linear gradient, then 20%, 30%, 50% constant gradient of 60% acetonitrile in neutral Na2HPO4 buffer. Peak fractions were pooled, evaporatively dried, and dissolved in ultrapure water. Finally, fraction A11 was analyzed combining tandem mass spectrometry and proteomic tools and two peptides (peptide 11 and 16) were identified. The hematopoietic effects of multiple fractions and the two peptides were measured using colony-forming units-erythroid (CFU-E), an indication of late erythroid progenitor cells and colony-forming units granulocyte-monocyte (CFU-GM), an indication of granulocyte and monocyte progenitor cells respectively on hematopoietic progenitor cells prepared from bone marrow (Till and Mcculloch 1961). RESULTS: Fraction A at 1g/kg and 2g/kg could increase RBC and WBC counts in 5-FU and radiation induced anemic mice models. Fraction A1 at 0.1mg/ml and 0.5mg/ml, exhibited stronger hematopoietic activity than fraction A2, both of which were subfractions from fraction A using IEX, by elevated CFU-E and CFU-GM of mouse bone marrow cells. Furthermore, fraction A11 at 0.1mg/ml showed stronger CFU-E and CFU-GM than fractions A12 to A14 from RPC separation. Finally, peptide 11 and peptide 16 were identified from tandem mass spectrometry and peptide 11 increased CFU-E and CFU-GM in a dose dependent manner. CONCLUSIONS: We combined multiple approaches including chromatography, mass spectrometry, cell-based assays, as well as animal studies to identify and demonstrate that the hematopoietic effect of Colla Corii Asini is at least in part from the peptidic components identified using our methodology. This is the first time to isolate peptidic components from Colla Corii Asini, and to provide molecular basis for its usage in treating anemia, which may particularly have the potential to benefit cancer patients suffering from myelosuppression due to radiotherapy or chemotherapy.


Subject(s)
Anemia/drug therapy , Collagen/chemistry , Drugs, Chinese Herbal/therapeutic use , Gelatin/therapeutic use , Hematinics/therapeutic use , Peptides/therapeutic use , Anemia/blood , Anemia/chemically induced , Animals , Blood Cell Count , Drugs, Chinese Herbal/pharmacology , Erythroid Precursor Cells/cytology , Erythroid Precursor Cells/drug effects , Female , Fluorouracil , Gamma Rays , Gelatin/pharmacology , Granulocyte-Macrophage Progenitor Cells/cytology , Granulocyte-Macrophage Progenitor Cells/drug effects , Hematinics/analysis , Hematinics/pharmacology , Hematopoiesis/drug effects , Medicine, Chinese Traditional , Mice, Inbred ICR , Peptides/analysis , Peptides/pharmacology
11.
Cancer Epidemiol Biomarkers Prev ; 10(6): 715-9, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11401925

ABSTRACT

Folate status is inversely related to the risk of colorectal cancer. Whether conventional blood measurements of folate status accurately reflect folate concentrations in the colorectal mucosa has been a controversial topic. This is an important issue because accurate measures of folate status in the colorectal mucosa are important for ascertaining the risk of colorectal cancer in epidemiological studies and for determining the effects of folate supplementation in clinical trials. We examined whether conventional blood measurements of folate and a more sensitive, inverse indicator of systemic folate status, serum homocysteine, accurately reflect folate concentrations in human colonic mucosa obtained by endoscopic biopsy. Study subjects (n = 20) were participants in a randomized trial that investigated the effect of folate supplementation (5 mg daily for 1 year) on provisional molecular markers of colon cancer. Blood samples and biopsies of normal rectosigmoid mucosa were obtained at baseline, at 6 months, and at 1 year. Serum, RBC, and colonic mucosal folate and serum homocysteine concentrations were determined. Colonic mucosal folate concentrations correlated directly with serum folate concentrators at each time point (r = 0.572-0.845; P < 0.015) and with RBC folate concentrations at 6 months and 1 year (r = 0.747-0.771; P < 0.001). Colonic mucosal folate concentrations correlated inversely with serum homocysteine concentrations at each time point (r = -0.622-0.666; P < 0.008). Systemic measures of folate status did not correlate with colonic mucosal folate concentrations among individuals receiving supplemental folate. Our observations indicate that colonic mucosal concentrations of folate may be predicted accurately by blood measurements of folate status only among individuals not ingesting supraphysiological quantities of folate.


Subject(s)
Adenoma/drug therapy , Colonic Neoplasms/drug therapy , Folic Acid/analysis , Hematinics/analysis , Intestinal Mucosa/chemistry , Adult , Diet , Dietary Supplements , Female , Folic Acid/administration & dosage , Folic Acid/blood , Hematinics/administration & dosage , Hematinics/blood , Homocysteine/blood , Humans , Male , Reproducibility of Results , Sensitivity and Specificity
13.
Sports Med ; 32(2): 125-42, 2002.
Article in English | MEDLINE | ID: mdl-11817997

ABSTRACT

The use of DNA-recombinant human epoetin-alfa (rhEPO) as a pharmacological ergogenic aid for the enhancement of aerobic performance is estimated to be practised by at least 3 to 7% of elite endurance sport athletes. rhEPO is synthesised from Chinese hamster ovary cells, and is nearly identical biochemically and immunologically to endogenous epoetin-alfa (EPO). In a clinical setting, rhEPO is used to stimulate erythrocyte production in patients with end-stage renal disease and anaemia. A limited number of human studies have suggested that rhEPO provides a significant erythropoietic and ergogenic benefit in trained individuals as evidenced by increments in haemoglobin, haematocrit, maximal oxygen uptake (VO2max) and exercise endurance time. The purpose of this review is to summarise the various technologies and methodologies currently available for the detection of illicit use of rhEPO in athletes. The International Olympic Committee (IOC) banned the use of rhEPO as an ergogenic aid in 1990. Since then a number of methods have been proposed as potential techniques for detecting the illegal use of rhEPO. Most of these techniques use indirect markers to detect rhEPO in blood samples. These indirect markers include macrocytic hypochromatic erythrocytes and serum soluble transferrin receptor (sTfr) concentration. Another indirect technique uses a combination of 5 markers of enhanced erythropoiesis (haematocrit, reticulocyte haematocrit, percentage of macrocytic red blood cells, serum EPO, sTfr) to detect rhEPO. The electrophoretic mobility technique provides a direct measurement of urine and serum levels of rhEPO, and is based on the principle that the rhEPO molecule is less negatively charged versus the endogenous EPO molecule. Isoelectric patterning/focusing has emerged recently as a potential method for the direct analysis of rhEPO in urine. Among these various methodologies, the indirect technique that utilises multiple markers of enhanced erythropoiesis appears to be the most valid, reliable and feasible protocol currently available for the detection of rhEPO in athletes. In August 2000, the IOC Medical Commission approved this protocol known as the 'ON model', and it was subsequently used in combination with a second, confirmatory test (isoelectric patterning) to detect rhEPO abusers competing in the 2000 Sydney Summer Olympics. This combined blood and urine test was approved with modifications by the IOC in November 2001 for use in the 2002 Salt Lake City Winter Olympics.


Subject(s)
Doping in Sports , Erythropoiesis/drug effects , Erythropoietin/analysis , Hematinics/analysis , Physical Endurance/drug effects , Electrophoresis/methods , Epoetin Alfa , Erythropoiesis/physiology , Erythropoietin/pharmacology , Erythropoietin/physiology , Hematinics/pharmacology , Humans , Isoelectric Focusing , Recombinant Proteins
14.
J Pharm Biomed Anal ; 23(6): 1039-44, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11095306

ABSTRACT

A study of the photolysis of folic acid in aqueous solution by visible radiation in the presence of riboflavin has been made. The second-order rate constants for the bimolecular interaction of folic acid and riboflavin have been determined in the pH range 4.0-9.0. The rate pH profile shows a gradual increase in the rate up to pH 6.2 (pHmax) followed by a decrease up to pH 9.0, depending upon the susceptibility of ionic species involved in the interaction. The rate of photolysis varies from 0.50 x 10(3) M(-1) min(-1) (pH 9.0) and 0.63 x 10(3) M(-1) min(-1) (pH 4.0) to 3.0 x 10(3) M(-1) min(-1) (pH 6.2) in the pH range studied. A HPLC method has been used for the assay of folic acid and its photoproducts, pterine-6-carboxylic acid and p-aminobenzoyl-L-glutamic acid in the presence of riboflavin.


Subject(s)
Folic Acid/analysis , Hematinics/analysis , Photolysis/drug effects , Photosensitizing Agents/pharmacology , Riboflavin/pharmacology , Chromatography, High Pressure Liquid , Hydrogen-Ion Concentration , Kinetics , Regression Analysis , Solutions
15.
Acta Clin Belg ; 69(1): 25-9, 2014.
Article in English | MEDLINE | ID: mdl-24635395

ABSTRACT

The recent Armstrong case, where more than 250 negative doping tests are confronted with the athlete's confession of erythropoietin use, blood doping, steroid, and growth hormone abuse, illustrates the limitations of current laboratory tests in detecting doping in sport. Despite numerous doping controls and simultaneous indications of common doping abuse among professional athletes in the last two decades, the number of positive urine tests for recombinant human erythropoietin (rHuEPO) remains remarkably low. Athletes are using various masking strategies, among them protease inhibitors, intravenous injections of rHuEPO and alternative erythropoiesis stimulating agents. As one of the countermeasures, the Athlete's Biological Passport has been introduced. The sensitivity of the Athlete's Biological Passport is limited if the effect of a low-dose doping remains within the intra-individual reference range. A possible solution could be the use of a novel Epo test (MAIIA Diagnostics). Another performance-enhancing strategy is the return to 'old' doping techniques, such as autologous blood transfusions. Several indirect methods to detect autologous blood transfusions have been proposed with the majority relying on changes in erythropoiesis-sensitive blood markers. Currently, an algorithm based on the haemoglobin (Hb) level concentration and the percentage of reticulocytes (OFF-hr model; Hb(g/l)-60·âˆš%ret) is approved by the World Anti-Doping Agency. Genetic factors have been identified which may interfere with test interpretation. A large inter- and intra-ethnic variation in testosterone glucuronidation and excretion has been described. Consideration of genetic variation should improve performance of the testosterone doping test. Taking into account the pre-analytical care and better tailoring of the threshold values could increase test sensitivity. Anti-doping laboratories should routinely adjust for multiple testing as failure of doping control to detect cheaters could lead to more frequent controls. Finally, despite the huge technological progress, there is a need for increased collaboration between physiologists, analytical chemists, biostatisticians, and ethicists to reduce doping in sport.


Subject(s)
Doping in Sports , Substance Abuse Detection/methods , Blood Transfusion, Autologous , Doping in Sports/methods , Doping in Sports/prevention & control , Hematinics/analysis , Human Growth Hormone/analysis , Humans , Testosterone/analysis
16.
Protein Pept Lett ; 21(10): 986-99, 2014.
Article in English | MEDLINE | ID: mdl-24975672

ABSTRACT

Glycoproteins are becoming increasingly relevant in therapeutics, including tissue plasminogen activator for the treatment of myocardial infarction and strokes, erythropoietin for anemia and various monoclonal antibody-based treatments for cancer. Protein N- and O-glycosylation is perhaps the most crucial and immensely complex posttranslational modification that proteins undergo, and its characterization presents a major challenge. This review will discuss current techniques for the characterization of glycoproteins, with a focus on therapeutic glycoproteins where available. The crucial analytical techniques, such as high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), and mass spectrometry (MS) will be described, alongside the necessary chemical labeling methods for sensitive detection. The well-established chemical and enzymatic methods for oligosaccharide release from proteins will be discussed, as will more modern methods based on exhaustive protein hydrolysis with non-specific proteases.


Subject(s)
Antineoplastic Agents/analysis , Cardiovascular Agents/analysis , Glycoproteins/analysis , Hematinics/analysis , Polysaccharides/analysis , Antineoplastic Agents/chemistry , Carbohydrate Sequence , Cardiovascular Agents/chemistry , Chromatography, High Pressure Liquid , Electrophoresis, Capillary , Fluorescent Dyes , Glycoproteins/chemistry , Glycosylation , Hematinics/chemistry , Humans , Molecular Sequence Data , Polysaccharides/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Staining and Labeling/methods
17.
Bioanalysis ; 4(13): 1681-90, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22831483

ABSTRACT

The misuse of medicines for performance enhancement in sport (doping) is not approved by regulatory agencies, and is illegal in many countries. In addition to the 'traditional' doping agents such as steroids, ß-blockers and blood transfusions, the list of agents and techniques used in doping is increasing and now includes newer medicines such as erythropoiesis-stimulating agents and growth hormones. Innovative new medicines are of particular interest as would-be dopers may believe them to be undetectable by current methods. Close collaboration between the biopharmaceutical industry and anti-doping agencies such as the World Anti-Doping Agency is critical to a successful anti-doping strategy. Industry is ideally placed to identify the doping potential of new medicines at early stages and to support early development of detection assays. A strong, united front between the biopharmaceutical industry and anti-doping agencies is essential to counter the misuse of medicines for performance enhancement, as well as to promote fair play and clean sport.


Subject(s)
Doping in Sports/prevention & control , Drug Industry , Performance-Enhancing Substances/administration & dosage , Public-Private Sector Partnerships , Substance Abuse Detection/methods , Government Agencies , Hematinics/analysis , Humans
18.
Drug Test Anal ; 4(11): 830-45, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22362605

ABSTRACT

Increasing the blood's capacity for oxygen transport by erythropoiesis-stimulating agents (ESAs) constitutes a prohibited procedure of performance enhancement according to the World Anti-Doping Agency (WADA). The advent of orally bio-available small-molecule ESAs such as hypoxia-inducible factor (HIF) stabilizers in the development of novel anti-anaemia therapies expands the list of potential ESA doping techniques. Here, the erythropoiesis-stimulating properties and doping relevance of experimental HIF-stabilizers, such as cobaltous chloride, 3,4-dihydroxybenzoic acid or GSK360A, amongst others, are discussed. The stage of clinical trials is reviewed for the anti-anaemia drug candidates FG-2216, FG-4592, GSK1278863, AKB-6548, and BAY85-3934. Currently available methods and strategies for the determination of selected HIF stabilizers in sports drug testing are based on liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). For the support of further analytical assay development, patents claiming distinct compounds for the use in HIF-mediated therapies are evaluated and exemplary molecular structures of HIF stabilizers presented. Moreover, data concerning the erythropoiesis-enhancing effects of the GATA inhibitors K7174 and K11706 as well as the lipidic small-molecule ESA PBI-1402 are elucidated the context of doping analysis.


Subject(s)
Hematinics/analysis , Hematinics/pharmacology , Hypoxia-Inducible Factor 1/metabolism , Small Molecule Libraries/analysis , Small Molecule Libraries/pharmacology , Substance Abuse Detection/methods , Anemia/drug therapy , Animals , Cobalt/analysis , Cobalt/pharmacology , Doping in Sports , Erythropoiesis/drug effects , GATA Transcription Factors/antagonists & inhibitors , Glycine/analogs & derivatives , Glycine/analysis , Glycine/pharmacology , Humans , Hydroxybenzoates/analysis , Hydroxybenzoates/pharmacology , Quinolones/analysis , Quinolones/pharmacology
19.
Pharmeur Bio Sci Notes ; 2011(1): 66-80, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21619857

ABSTRACT

A physico-chemical method has been developed as an alternative to the current bioassay in normocythaemic mice for estimating the biological activity of erythropoietin batches. Capillary zone electrophoresis was used for quantification of the isoforms and their substructures were further elucidated by N-glycan mapping techniques. The analytical study was carried out on a total of 40 batches of epoetin beta which were selected to cover an adequate range of precisely established potency values. The relationship between the biological and chemical parameters was evaluated statistically in order to identify suitable covariates for the prediction of the biological activity. Out of several alternatives, a prediction model which is based on the percentages of isoforms per batch and the degree of sialidation was selected and tested. This model is comparable in terms of accuracy to the established in vivo bioassay, but is far superior in terms of precision. Further advantages of the method are improved animal welfare and savings in time and effort. The question whether the prediction model already meets the requirements for replacing the bioassay according to the ICH guideline Q6B is discussed.


Subject(s)
Animal Testing Alternatives , Electrophoresis, Capillary , Erythropoietin/analysis , Hematinics/analysis , Amino Acid Sequence , Animal Testing Alternatives/methods , Animal Testing Alternatives/standards , Animals , Anion Exchange Resins , Biological Assay , Chromatography, Ion Exchange , Erythropoietin/chemistry , Erythropoietin/pharmacology , Erythropoietin/standards , Glycosylation , Hematinics/chemistry , Hematinics/pharmacology , Hematinics/standards , Hematopoiesis/drug effects , Linear Models , Mice , Models, Biological , Molecular Sequence Data , Principal Component Analysis , Protein Conformation , Protein Isoforms , Quality Control , Recombinant Proteins , Reproducibility of Results , Sialic Acids/analysis , Surface Plasmon Resonance
20.
Curr Med Res Opin ; 27(12): 2241-3, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21992082

ABSTRACT

BACKGROUND: Sodium ferric gluconate in complex (SFG) is used to treat iron deficiency anemia in patients aged ≥6 years undergoing chronic hemodialysis and receiving supplemental epoetin therapy. Both the branded product (Ferrlecit, branded SFG) and a new generic version of sodium ferric gluconate in complex (Nulecit; generic SFG) are provided in 5 mL vials. SFG may be administered by slow intravenous (IV) injection of the undiluted product or by 1 h IV infusion after dilution in 100 mL 0.9% sodium chloride. This study evaluated the short-term stability of undiluted and diluted generic SFG at room temperature and under refrigeration. METHODS: Samples of generic SFG undiluted in 10 mL syringes or diluted in IV infusion bags containing 0.9% sodium chloride solution were stored at room temperature or under refrigerated conditions (2-8°C). Samples at room temperature were stored for ≤48 h if undiluted and for ≤24 h if diluted. All refrigerated samples were stored for ≤7 days. Parameters evaluated were elemental iron (Fe) concentration and SFG apparent molecular weight. All tests were performed on two lots of the generic product. RESULTS: Fe concentrations were identical in both lots and did not vary substantially over time under different conditions of storage or dilution. SFG apparent molecular weight varied across all samples from 306,000 to 354,000 Daltons, well within the range of 289,000 to 440,000 Daltons specified as the molecular weight in the FDA-approved prescribing information. CONCLUSION: Iron content and SFG apparent molecular weight were stable under all experimental conditions. Undiluted generic SFG was stable for ≥2 days at room temperature and ≥7 days under refrigerated conditions, and generic SFG diluted in IV infusion bags containing 0.9% sodium chloride solution was stable for ≥1 day at room temperature and ≥7 days under refrigerated conditions.


Subject(s)
Drugs, Generic/analysis , Ferric Compounds/analysis , Hematinics/analysis , Sucrose/analysis , Sweetening Agents/analysis , Adolescent , Adult , Aged , Aged, 80 and over , Anemia/drug therapy , Child , Drug Stability , Drugs, Generic/chemistry , Drugs, Generic/therapeutic use , Female , Ferric Compounds/chemistry , Ferric Compounds/therapeutic use , Hematinics/chemistry , Hematinics/therapeutic use , Humans , Male , Middle Aged , Sucrose/chemistry , Sucrose/therapeutic use , Sweetening Agents/chemistry , Sweetening Agents/therapeutic use
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