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Stingl JC, Bartels H, Viviani R, Lehmann ML, Brockmöller J. Relevance of UDP-glucuronosyltransferase polymorphisms for drug dosing: A quantitative systematic review. Pharmacol Ther 2013; 141:92-116. [PMID: 24076267 DOI: 10.1016/j.pharmthera.2013.09.002] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 09/10/2013] [Indexed: 01/01/2023]
Abstract
UDP-glucuronosyltransferases (UGT) catalyze the biotransformation of many endobiotics and xenobiotics, and are coded by polymorphic genes. However, knowledge about the effects of these polymorphisms is rarely used for the individualization of drug therapy. Here, we present a quantitative systematic review of clinical studies on the impact of UGT variants on drug metabolism to clarify the potential for genotype-adjusted therapy recommendations. Data on UGT polymorphisms and dose-related pharmacokinetic parameters in man were retrieved by a systematic search in public databases. Mean estimates of pharmacokinetic parameters were extracted for each group of carriers of UGT variants to assess their effect size. Pooled estimates and relative confidence bounds were computed with a random-effects meta-analytic approach whenever multiple studies on the same variant, ethnic group, and substrate were available. Information was retrieved on 30 polymorphic metabolic pathways involving 10 UGT enzymes. For irinotecan and mycophenolic acid a wealth of data was available for assessing the impact of genetic polymorphisms on pharmacokinetics under different dosages, between ethnicities, under comedication, and under toxicity. Evidence for effects of potential clinical relevance exists for 19 drugs, but the data are not sufficient to assess effect size with the precision required to issue dose recommendations. In conclusion, compared to other drug metabolizing enzymes much less systematic research has been conducted on the polymorphisms of UGT enzymes. However, there is evidence of the existence of large monogenetic functional polymorphisms affecting pharmacokinetics and suggesting a potential use of UGT polymorphisms for the individualization of drug therapy.
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Affiliation(s)
- J C Stingl
- Research Division, Federal Institute for Drugs and Medical Devices, Bonn, Germany; Translational Pharmacology, University of Bonn Medical Faculty, Germany.
| | - H Bartels
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, University of Ulm, Germany
| | - R Viviani
- Department of Psychiatry and Psychotherapy III, University of Ulm, Germany
| | - M L Lehmann
- Research Division, Federal Institute for Drugs and Medical Devices, Bonn, Germany
| | - J Brockmöller
- Institute of Clinical Pharmacology, University of Göttingen, Germany
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Luu-The V. Assessment of steroidogenesis and steroidogenic enzyme functions. J Steroid Biochem Mol Biol 2013; 137:176-82. [PMID: 23770321 DOI: 10.1016/j.jsbmb.2013.05.017] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 04/18/2013] [Accepted: 05/25/2013] [Indexed: 10/26/2022]
Abstract
There is some confusion in the literature about steroidogenesis in endocrine glands and steroidogenesis in peripheral intracrine tissues. The objective of the present review is to bring some clarifications and better understanding about steroidogenesis in these two types of tissues. Concerns about substrate specificity, kinetic constants and place of enzymes in the pathway have been discussed. The role of 17α-hydroxylase/17-20 lyase (CYP17A1) in the production of dehydroepiandrosterone and back-door pathways of dihydrotestosterone biosynthesis is also analyzed. This article is part of a Special Issue entitled "Synthesis and biological testing of steroid derivatives as inhibitors".
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Affiliation(s)
- Van Luu-The
- Research Center in Molecular Endocrinology, Oncology and Human Genomics (CREMOGH) and Department of Molecular Medicine, Faculty of Medicine, Laval University and the CHU de Quebec Research Center, Quebec City, Canada.
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Heydel JM, Coelho A, Thiebaud N, Legendre A, Bon AML, Faure P, Neiers F, Artur Y, Golebiowski J, Briand L. Odorant-Binding Proteins and Xenobiotic Metabolizing Enzymes: Implications in Olfactory Perireceptor Events. Anat Rec (Hoboken) 2013; 296:1333-45. [DOI: 10.1002/ar.22735] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 02/01/2013] [Accepted: 02/26/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Jean-Marie Heydel
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Alexandra Coelho
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Nicolas Thiebaud
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Arièle Legendre
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Anne-Marie Le Bon
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Philippe Faure
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Fabrice Neiers
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Yves Artur
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
| | - Jérôme Golebiowski
- Université de Nice Sophia Antipolis; CNRS UMR7272, Institut de Chimie de Nice; F-06108 Nice Cedex 2 France
| | - Loïc Briand
- INRA UMR1324, CNRS UMR6265; Université de Bourgogne, Centre des Sciences du Goût et de l'Alimentation; F-21000 Dijon France
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Perreault M, Gauthier-Landry L, Trottier J, Verreault M, Caron P, Finel M, Barbier O. The Human UDP-glucuronosyltransferase UGT2A1 and UGT2A2 enzymes are highly active in bile acid glucuronidation. Drug Metab Dispos 2013; 41:1616-20. [PMID: 23756265 DOI: 10.1124/dmd.113.052613] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Bile acids (BA) are essential modulators of lipid, glucose, and cholesterol homeostasis, but they exert cytotoxic effects in the cholestatic liver. Glucuronidation, catalyzed by the UDP-glucuronosyltransferase (UGT) enzymes is a pharmacologically relevant BA detoxification process. The present study characterized the BA-conjugating activity of the little-studied human UGTs of subfamily 2A: UGT2A1, 2A2, and 2A3. Recombinant UGT2As, expressed in baculovirus-infected insect cells, were assayed for the glucuronidation of six major bile acids: chenodeoxycholic acid (CDCA), cholic acid (CA), lithocholic acid (LCA), deoxycholic acid (DCA), hyocholic acid (HCA) and hyodeoxycholic acid (HDCA). UGT2A3 exhibited detectable but very low activity with all the tested BA substrates. UGT2A1 was highly efficient in forming LCA-3 and LCA-24G, CDCA-24, DCA-24, HCA-24, and HDCA-24G, whereas UGT2A2 was the most active enzyme for CA-24G and CDCA-24G formation and also was able to generate HDCA-6G, HDCA-24G, LCA-24G, and HCA-24G. The Km values of UGT2A1 varied between 102.2 ± 14.3 µM and 2.4 ± 1.2 mM. With the exception of CA-24G, a low affinity substrate for UGT2A2, all the Km values for UGT2A2 were in the 100 to 400 µM range. We demonstrate the high reactivity of the human UGT2A1 and UGT2A2 for bile acid glucuronidation. The physiologic importance of these reactions to BA disposition remains, however, to be clarified in vivo.
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Affiliation(s)
- Martin Perreault
- Laboratory of Molecular Pharmacology, CHU-Québec Research Centre, Faculty of Pharmacy, Laval University, Québec City, Québec, Canada
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55
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The cucurbitacins E, D and I: Investigation of their cytotoxicity toward human chondrosarcoma SW 1353 cell line and their biotransformation in man liver. Toxicol Lett 2013. [DOI: 10.1016/j.toxlet.2012.11.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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56
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Martínez-Brito D, Correa Vidal MT, de la Torre X, García-Mir V, Ledea Lozano O, Granda Fraga M. Reference ranges for the urinary steroid profile in a Latin-American population. Drug Test Anal 2013; 5:619-26. [DOI: 10.1002/dta.1448] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 09/28/2012] [Accepted: 11/20/2012] [Indexed: 11/06/2022]
Affiliation(s)
| | | | | | - V. García-Mir
- Pharmacy and Food Institute; Havana University; Cuba
| | | | - M. Granda Fraga
- Antidoping Laboratory; Sport Medicine Institute; Havana; Cuba
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Schulze J, Johansson M, Thörngren JO, Garle M, Rane A, Ekström L. SULT2A1 Gene Copy Number Variation is Associated with Urinary Excretion Rate of Steroid Sulfates. Front Endocrinol (Lausanne) 2013; 4:88. [PMID: 23874324 PMCID: PMC3709130 DOI: 10.3389/fendo.2013.00088] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 07/01/2013] [Indexed: 11/13/2022] Open
Abstract
Human cytosolic sulfotransferases (SULT) 2A1 is the main enzyme involved in the sulfate conjugation of dehydroepiandrosterone, a weak androgen, and the main androgen precursor, whereas estrogens are mainly conjugated by SULT1A1. Here we have identified a copy number variation (CNV) polymorphism in the SULT2A1 gene in a Swedish population including healthy men (N = 30). Moreover, the CNV of SULT1A1 and SULT2A1 was further characterized in relation to urinary levels of androgen sulfate metabolites before and after an intramuscular dose of 500 mg testosterone enanthate. Individuals expressing two or more CNVs excrete 80 and 40% higher levels of DHEAS (p = 0.02) and androsteroneS (p = 0.01), respectively as compared to individuals with one gene copy. The mean area under the urine concentration time-curve from time 0 (prior to the administration of 500 mg testosterone) to 15 days post dose values were 80% higher for DHEAS (p = 0.046) and testosteroneS (p = 0.019) in individuals with two and three SULT2A1 gene copies as compared to individuals with one gene copy. The SULT1A1 CNV on the other hand did not affect the sulfation activity toward the androgens. In conclusion our results indicate that functional CNV polymorphisms in SULT2A1 and SULT1A1 are common in a Swedish population and that SULT2A1 CNV is associated with the urinary concentrations of androgen sulfate metabolites.
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Affiliation(s)
- Jenny Schulze
- Laboratory Medicine, Division Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Maria Johansson
- Laboratory Medicine, Division Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - John-Olof Thörngren
- Doping Control Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Mats Garle
- Laboratory Medicine, Division Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden
- Doping Control Laboratory, Karolinska University Hospital, Stockholm, Sweden
| | - Anders Rane
- Laboratory Medicine, Division Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Lena Ekström
- Laboratory Medicine, Division Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden
- *Correspondence: Lena Ekström, Division of Clinical Pharmacology, Karolinska University Hospital, C1-68, SE-14186 Stockholm, Sweden e-mail:
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58
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Lundmark J, Gårevik N, Thörngren JO, Garle M, Ekström L, Rane A, Schulze JJ. Non-steroidal anti-inflammatory drugs do not influence the urinary testosterone/epitestosterone glucuronide ratio. Front Endocrinol (Lausanne) 2013; 4:51. [PMID: 23720652 PMCID: PMC3655282 DOI: 10.3389/fendo.2013.00051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 04/18/2013] [Indexed: 11/19/2022] Open
Abstract
The UDP Glucuronosyl Transferase (UGT) enzymes are important in the pharmacokinetics, and conjugation, of a variety of drugs including non-steroidal anti-inflammatory drugs (NSAIDs) as well as anabolic androgenic steroids (AAS). Testosterone glucuronidation capacity is strongly associated with a deletion polymorphism in the UGT2B17 gene. As the use of high doses of NSAIDs has been observed in athletes there is a risk for a drug-drug interaction that may influence the doping tests for AAS. In vitro studies show inhibitory potential on UGT2B7, 2B15, and 2B17 enzymes by NSAIDs. The aim of this study was to investigate if concomitant use of NSAIDs and a single dose of testosterone enanthate would affect the excretion rate of testosterone and epitestosterone glucuronide (TG and EG) as well as the T/E ratio, thereby affecting the outcome of the testosterone doping test. The study was designed as an open, randomized, cross-over study with subjects being their own control. The 23 male healthy volunteers, with either two, one or no allele (ins/ins, ins/del, or del/del) of the UGT2B17 gene, received the maximum recommended dose of NSAID (Ibuprofen or Diclofenac) for 6 days. On day three, 500 mg of testosterone enanthate was administered. Spot urine samples were collected for 17 days. After a wash-out period of 4 months the volunteers received 500 mg testosterone enanthate only, with subsequent spot urine collection for 14 days. The glucuronides of testosterone and epitestosterone were quantified. NSAIDs did not affect the excretion of TG or EG before the administration of testosterone. The concomitant use of NSAIDs and testosterone slightly increased the TG excretion while the EG excretion was less suppressed compared to testosterone use only. The effects of the NSAIDs on the TG and EG excretion did not differ between the UGT2B17 genotype groups. In conclusion, the outcome of testosterone doping tests does not seem to be affected by the use of NSAIDs.
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Affiliation(s)
- Jonas Lundmark
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
| | - Nina Gårevik
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
| | - John-Olof Thörngren
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
| | - Mats Garle
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
| | - Lena Ekström
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
| | - Anders Rane
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
| | - Jenny J. Schulze
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska InstitutetStockholm, Sweden
- *Correspondence: Jenny J. Schulze, Clinical Pharmacology C1:68, Karolinska University Hospital, Huddinge, 141 86 Stockholm, Sweden. e-mail:
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59
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Bang AK, Jørgensen N, Rajpert-De Meyts E, Juul A. UGT2B17 Genotype and the Pharmacokinetic Serum Profile of Testosterone during Substitution Therapy with Testosterone Undecanoate. A Retrospective Experience from 207 Men with Hypogonadism. Front Endocrinol (Lausanne) 2013; 4:94. [PMID: 23908645 PMCID: PMC3725801 DOI: 10.3389/fendo.2013.00094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 07/15/2013] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Testosterone (T) is mainly excreted in the urine as testosterone glucuronide (TG). This glucuronidation is partly dependent on the UGT2B17 genotype, and TG excretion is therefore lower in men having the UGT2B17 deletion. However, the possible influence of UGT2B17 genotype on serum T during androgen therapy is unknown. We retrospectively investigated the possible association between the UGT2B17 gene polymorphism and serum T levels in hypogonadal men during Testosterone undecanoate (TU) substitution therapy. SUBJECTS AND METHODS Two hundred and seven patients treated with TU (Nebido(®)) were genotyped by quantitative polymerase chain reaction for the UGT2B17 deletion polymorphism. All were given 1000 mg TU per injection at 0, 6, and 18 weeks. Blood samples were taken 2 and 6 weeks after the first and second injection, prior to the third injection, and after 2-3 years of treatment. We analyzed for the levels of T, luteinizing hormone (LH), sex-hormone-binding globulin, estradiol, prostate specific antigen, hematocrit, hemoglobin, and total cholesterol. RESULTS The UGT2B17 genotype frequency was: ins/ins: 42%, ins/del: 44%, and del/del: 14%. During the initial 18 weeks of TU treatment, large intra- and inter-individual variations in serum T levels were observed. Large peaks in T levels, ranging from 6.7 to 69.5 nmol/l, were noted 2 weeks after injections, regardless of the genotype. T levels did not differ between the three genotypes prior to the third injection, but the del/del group had significantly lower levels of LH. At follow-up after 2-3 years, the injection interval or daily T dosage was not dependent on the UGT2B17 genotype. CONCLUSION In conclusion, we found large intra- and inter-individual variations in serum T during standard TU treatment regimen in hypogonadal men. Only subtle differences in serum T and LH were noted according to UGT2B17 genotype, which however suggest that the UGT2B17 genotype exert modest influence on the pharmacokinetic profile of T after TU treatment.
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Affiliation(s)
- Anne Kirstine Bang
- Department of Growth and Reproduction, Faculty of Health and Medical Sciences, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Anne Kirstine Bang, Department of Growth and Reproduction, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark e-mail:
| | - Niels Jørgensen
- Department of Growth and Reproduction, Faculty of Health and Medical Sciences, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Ewa Rajpert-De Meyts
- Department of Growth and Reproduction, Faculty of Health and Medical Sciences, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Anders Juul
- Department of Growth and Reproduction, Faculty of Health and Medical Sciences, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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Jenkinson C, Petroczi A, Naughton DP. Effects of Dietary Components on Testosterone Metabolism via UDP-Glucuronosyltransferase. Front Endocrinol (Lausanne) 2013; 4:80. [PMID: 23847592 PMCID: PMC3703584 DOI: 10.3389/fendo.2013.00080] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 06/20/2013] [Indexed: 01/27/2023] Open
Abstract
THE POTENTIAL INTERFERENCE IN TESTOSTERONE METABOLISM THROUGH INGESTED SUBSTANCES HAS RAMIFICATIONS FOR: (i) a range of pathologies such as prostate cancer, (ii) medication contra-indications, (iii) disruption to the endocrine system, and (iv) potential confounding effects on doping tests. Conjugation of anabolic steroids during phase II metabolism, mainly driven by UDP-glucuronosyltransferase (UGT) 2B7, 2B15, and 2B17, has been shown to be impaired in vitro by a range of compounds including xenobiotics and pharmaceuticals. Following early reports on the effects of a range of xenobiotics on UGT activity in vitro, the work was extended to reveal similar effects with common non-steroidal anti-inflammatory drugs. Notably, recent studies have evidenced inhibitory effects of the common foodstuffs green tea and red wine, along with their constituent flavonoids and catechins. This review amalgamates the existing evidence for the inhibitory effects of various pharmaceutical and dietary substances on the rate of UGT glucuronidation of testosterone; and evaluates the potential consequences for health linked to steroid levels, interaction with treatment drugs metabolized by the UGT enzyme and steroid abuse in sport.
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Affiliation(s)
- Carl Jenkinson
- School of Life Sciences, Kingston University, Kingston upon Thames, UK
| | - Andrea Petroczi
- School of Life Sciences, Kingston University, Kingston upon Thames, UK
| | - Declan P. Naughton
- School of Life Sciences, Kingston University, Kingston upon Thames, UK
- *Correspondence: Declan P. Naughton, School of Life Sciences, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey KT1 2EE, UK e-mail:
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Bushey RT, Lazarus P. Identification and functional characterization of a novel UDP-glucuronosyltransferase 2A1 splice variant: potential importance in tobacco-related cancer susceptibility. J Pharmacol Exp Ther 2012; 343:712-24. [PMID: 22984225 PMCID: PMC3500542 DOI: 10.1124/jpet.112.198770] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 09/12/2012] [Indexed: 12/13/2022] Open
Abstract
UDP-glucuronosyltransferase (UGT) 2A1 is a respiratory and aerodigestive tract-expressing phase II detoxifying enzyme that metabolizes various xenobiotics including polycyclic aromatic hydrocarbons (PAHs). In the present study, a novel exon 3 deletion splice variant was identified for UGT2A1 (UGT2A1Δexon3). As determined by reverse transcription-polymerase chain reaction (PCR), UGT2A1Δexon3 was shown to be expressed in various tissues including lung, trachea, larynx, tonsil, and colon. The ratio of UGT2A1Δexon3/wild-type UGT2A1 expression was highest in colon (0.79 ± 0.08) and lung (0.42 ± 0.12) as determined by real-time PCR; an antibody specific to UGT2A1 showed splice variant protein (UGT2A1_i2) to wild-type protein (UGT2A1_i1) ratios in the range of 0.5 to 0.9 in these tissues. Using ultra-pressure liquid chromatography, we found that homogenates prepared from UGT2A1_i2-overexpressing human embryonic kidney 293 cells exhibited no glucuronidation activity against PAHs, including benzo[a]pyrene-7,8-dihydrodiol (B[a]P-7,8-diol). An inducible in vitro system was created to determine the effect of UGT2A1_i2 expression on UGT2A1_i1 activity. Increasing UGT2A1_i2 levels resulted in a significant (p < 0.01) decrease in the UGT2A1_i1 V(max) against 1-hydroxy (OH)-pyrene, 3-OH-benzo[a]pyrene, and B[a]P-7,8-diol; no significant changes in K(M) were observed for any of the three substrates. Coimmunoprecipitation experiments suggested the formation of UGT2A1_i1 and UGT2A1_i2 hetero-oligomers and UGT2A1_i1 homo-oligomers; coexpression of UGT2A1_i1 or UGT2A1_i2 with other UGT1A or UGT2B enzymes caused no change in UGT1A or UGT2B glucuronidation activity. These data suggest that a novel UGT2A1 splice variant regulates UGT2A1-mediated glucuronidation activity via UGT2A1-specific protein-protein interactions, and expression of this variant could play an important role in the detoxification of carcinogens within target tissues for tobacco carcinogenesis.
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Affiliation(s)
- Ryan T Bushey
- Department of Pharmacology, Penn State University College of Medicine, Hershey, PA 17033, USA
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Abstract
The large variation in disposition known for most drugs is also true for anabolic androgenic steroids. Genetic factors are probably the single most important cause of this variation. Further, there are reasons to believe that there is a corresponding variation in efficacy of doping agents. Doped individuals employ a large variety of doping strategies in respect of choice of substance, dose, dose interval, duration of treatment and use of other drugs for enforcement of effects or correction of side effects. Metabolic steps up-stream and down-stream of testosterone are genetically variable and contribute substantially to the variation in disposition of testosterone, the most common doping agent in sports and in society. Large inter- and intra-ethnic variation in testosterone glucuronidation and excretion is described as well as the pit-falls in evaluation of testosterone doping test results. The hydrolysis and bioactivation of testosterone enanthate is also genetically variable yielding a 2-3 fold variation in excretion rate and serum concentration, thereby implicating a substantial variation in 'efficacy' of testosterone. Given this situation it is logical to adopt the new findings in the doping control programme. The population based cut-off level for the testosterone : epitestosterone ratio should be replaced by a Bayesian interpretation of consecutive tests in the same individual. When combined with the above genetic information the sensitivity of the test is considerably improved. The combination of the three approaches should reduce the rate of falsely negative or positive results and the number of expensive follow-up tests, stipulated by the World Anti-Doping Agency.
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Affiliation(s)
- Anders Rane
- Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden.
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Human UDP-glucuronosyltransferase UGT2A2: cDNA construction, expression, and functional characterization in comparison with UGT2A1 and UGT2A3. Pharmacogenet Genomics 2012; 19:923-34. [PMID: 19858781 DOI: 10.1097/fpc.0b013e3283330767] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Characterize the expression and glucuronidation activities of the human uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT) 2A2. METHOD UGT2A1 was cloned from nasal mucosa mRNA. Synthetic cDNA for UGT2A2 was constructed assuming exon sharing between UGT2A1 and UGT2A2 (Mackenzie et al., Pharmacogenetics and Genomics 2005, 15:677-685). Exon 1 of UGT2A2 was amplified from genomic DNA and combined with exons 2-6 of UGT2A1. UGT2A3 was cloned from liver mRNA. Quantitative reverse-transcribed-PCR (RT-PCR) was used to evaluate the expression of all the three UGTs of subfamily 2A in different tissues. Recombinant UGT2A1, UGT2A2 and UGT2A3 were expressed in baculovirus-infected insect cells and analyzed for glucuronidation activity towards different substrates. RESULTS DNA sequencing of RT-PCR products from human nasal mucosa mRNA, confirmed exon sharing between UGT2A1 and UGT2A2. In addition, it indicated that the N-terminal signal peptide sequence of UGT2A2 is the longest among the human UGTs. Quantitative RT-PCR revealed that both UGT2A1 and UGT2A2 are mainly expressed in the nasal mucosa, and that their expression level in fetal samples was much higher than in adults. Activity assays with recombinant UGTs 2A1-2A3 showed broad substrate selectivity for UGT2A1 and UGT2A2. Although glucuronidation rates and substrate affinities were mostly higher in UGT2A1, the Km values for UDP-glucuronic acid were similar in both UGTs. In addition, there were regioselectivity differences between the two UGTs and, with a few substrates, particularly ethinylestradiol, the activity of UGT2A2 was higher. CONCLUSION UGT2A2 is mainly expressed in the nasal mucosa and it has glucuronidation activity towards several different endobiotic and xenobiotic substrates.
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Abstract
BACKGROUND UGT1A4 is primarily expressed in the liver and exhibits catalytic activities for various drugs. Amongst the few UGT1A4 polymorphisms evaluated, studies support the alteration of UGT1A4-mediated glucuronidation by a few variations including the Pro²⁴Thr and Leu⁴⁸Val variants (referred to as UGT1A4*2 and *3). METHODS We therefore investigated genetic mechanisms that might contribute to interindividual variation in UGT1A4 expression and activity. The UGT1A4 gene was sequenced from -4963 bp relative to the ATG to 2000 bp after the first exon in 184 unrelated Caucasians and African-Americans. RESULTS We identified a large number of genetic variations, including 13 intronic, 39 promoter, as well as 14 exonic polymorphisms, with 10 that lead to amino-acid changes. Of the nucleotide variations found in the -5 kb promoter region, five are located in the proximal region (first 500 bp), and positioned in putative HNF-1 and OCT-1 binding sites. Four of these variants, placed at -163, -219, -419 and -463, are in complete linkage disequilibrium with the Leu⁴⁸Val coding region variant and with several variants in the upstream region of the promoter. Transient transfections of reference and variant promoter constructs (from position -500 to +1) in different cell lines with or without co-expression of HNF-1 and/or OCT-1 showed limited effect of these variations. CONCLUSION Additional functional studies on promoter variants are still required to predict their potential influence on UGT1A4 expression in vivo. Besides, several coding variants significantly modified the enzyme kinetics for tamoxifen and Z-4-hydroxytamoxifen (Val⁴⁸, Asp⁵⁰, Gln⁵⁶, Phe¹⁷⁶, Asn²⁵⁰, Leu²⁷⁶) and are expected to have a potential in vivo effect.
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65
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Okano M, Ueda T, Nishitani Y, Kano H, Ikekita A, Kageyama S. UDP-glucuronosyltransferase 2B17 genotyping in Japanese athletes and evaluation of the current sports drug testing for detecting testosterone misuse. Drug Test Anal 2012; 5:166-81. [DOI: 10.1002/dta.1394] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Revised: 06/19/2012] [Accepted: 07/08/2012] [Indexed: 11/08/2022]
Affiliation(s)
- Masato Okano
- Anti-Doping Laboratory; Mitsubishi Chemical Medience Corporation; 3-30-1 Shimura, Itabashi-ku; Tokyo; 174-8555; Japan
| | - Toshihiko Ueda
- Advanced Medical Science Research Center; Mitsubishi Chemical Medience Corporation; 3-30-1 Shimura, Itabashi-ku; Tokyo; 174-8555; Japan
| | - Yasunori Nishitani
- Anti-Doping Laboratory; Mitsubishi Chemical Medience Corporation; 3-30-1 Shimura, Itabashi-ku; Tokyo; 174-8555; Japan
| | - Hiroko Kano
- Anti-Doping Laboratory; Mitsubishi Chemical Medience Corporation; 3-30-1 Shimura, Itabashi-ku; Tokyo; 174-8555; Japan
| | - Ayako Ikekita
- Anti-Doping Laboratory; Mitsubishi Chemical Medience Corporation; 3-30-1 Shimura, Itabashi-ku; Tokyo; 174-8555; Japan
| | - Shinji Kageyama
- Anti-Doping Laboratory; Mitsubishi Chemical Medience Corporation; 3-30-1 Shimura, Itabashi-ku; Tokyo; 174-8555; Japan
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66
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Jenkinson C, Petroczi A, Barker J, Naughton DP. Dietary green and white teas suppress UDP-glucuronosyltransferase UGT2B17 mediated testosterone glucuronidation. Steroids 2012; 77:691-5. [PMID: 22429924 DOI: 10.1016/j.steroids.2012.02.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 02/03/2012] [Accepted: 02/29/2012] [Indexed: 11/18/2022]
Abstract
The anabolic steroid testosterone can be used by athletes to enhance athletic performance and muscle growth. UDP-glucuronosyltransferase (UGT2B17) is the key enzyme involved in the glucuronidation of testosterone to testosterone glucuronide, which also serves as a marker for the testosterone/epitestosterone (T/E) ratio used to detect testosterone abuse in sport. Inhibitors of testosterone glucuronidation could have an impact on circulating testosterone levels, thus aiding performance, as well as potentially affecting the urinary T/E ratio and therefore masking testosterone abuse. Previous reports have revealed that non-steroidal, anti-inflammatory drugs, diclofenac and ibuprofen, inhibit the UGT2B17 enzyme. The aim of this study is to analyse dietary tea samples for inhibition of testosterone glucuronidation and, where inhibition is present, to identify the active compounds. Analysis of testosterone glucuronidation was conducted by performing UGT2B17 assays with detection of un-glucuronidated testosterone using high performance liquid chromatography. The results from this study showed that testosterone glucuronidation was inhibited by the green and white tea extracts, along with specific catechin compounds, notably: epicatechin, epigallocatechin gallate (EGCG) and catechin gallate. The IC50 inhibition value for EGCG was determined, using a Dixon plot, to be 64 μM, equalling the most active NSAID inhibitor diclofenac. Thus, common foodstuffs and their constituents, for the first time, have been identified as inhibitors of a key enzyme involved in testosterone glucuronidation. Whilst these common compounds are not substrates of the UGT2B17 enzyme, we showed that they inhibit testosterone glucuronidation which may have implications on current doping control in sport.
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Affiliation(s)
- Carl Jenkinson
- School of Life Sciences, Kingston University, London, UK.
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67
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Deshmukh NIK, Barker J, Petroczi A, Naughton DP. Detection of testosterone and epitestosterone in human hair using liquid chromatography-tandem mass spectrometry. J Pharm Biomed Anal 2012; 67-68:154-8. [PMID: 22559991 DOI: 10.1016/j.jpba.2012.04.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 03/30/2012] [Accepted: 04/09/2012] [Indexed: 11/17/2022]
Abstract
The feasibility of using hair analysis as a complimentary test in doping control has received increased attention in the scientific community. The aim of the study was to take a step forward to this goal and develop a method that, for the first time, is able to detect testosterone (T) and epitestosterone (E) in human hair, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and alkali digestion followed by extraction using pentane. The method was linear within the quantification range of 0.25-100 pg/mg for T and 0.5-100 pg/mg for E, with determination coefficient (r²) values >0.9987. The limits of detection for T and E were 0.1 pg/mg and 0.25 pg/mg respectively. The accuracy, precision and extraction recovery of the assay were satisfactory for the detection of T and E when ca. 50 mg hair was processed. The validated method was successfully applied for the analysis of 75 hair samples collected from healthy volunteers (65.3% males), with the concentration of T between 0.7-11.81 pg/mg and 0.33-6.05 pg/mg and the concentration of E between 0.63-8.27 pg/mg and 0.52-3.88 pg/mg in males and in females respectively. In males, the T levels were significantly higher (p=0.020) but there was no difference in the E levels (p=0.359). However, E was not detectable in 34 samples (of which 19 were females). The T and E levels showed linear correlation (r=0.698, p<0.001) with average T/E ratio of 1.32±0.7. The newly developed analytical method was rapid, facile, sensitive, selective, reproducible and reliable for determining the levels of T and E in hair and thus for calculating the T/E ratio in hair.
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68
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Sneitz N, Krishnan K, Covey DF, Finel M. Glucuronidation of the steroid enantiomers ent-17β-estradiol, ent-androsterone and ent-etiocholanolone by the human UDP-glucuronosyltransferases. J Steroid Biochem Mol Biol 2011; 127:282-8. [PMID: 21899827 PMCID: PMC3234363 DOI: 10.1016/j.jsbmb.2011.08.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 07/29/2011] [Accepted: 08/16/2011] [Indexed: 11/22/2022]
Abstract
Steroids enantiomers are interesting compounds for detailed exploration of drug metabolizing enzymes, such as the UDP-glucuronosyltransferases (UGTs). We have now studied the glucuronidation of the enantiomers of estradiol, androsterone and etiocholanolone by the 19 human UGTs of subfamilies 1A, 2A and 2B. The results reveal that the pattern of human UGTs of subfamily 2B that glucuronidate ent-17β-estradiol, particularly 2B15 and 2B17, resembles the glucuronidation of epiestradiol (17α-estradiol) rather than 17β-estradiol, the main physiological estrogen. The UGTs of subfamilies 1A and 2A exhibit higher degree of regioselectivity than enantioselectivity in the conjugation of these estradiols, regardless of whether the activity is primarily toward the non-chiral site, 3-OH (UGT1A1, UGT1A3, UGT1A7, UGT1A8 and, above all, UGT1A10), or the 17-OH (UGT1A4). In the cases of etiocholanolone and androsterone, glucuronidation of the ent-androgens, like the conjugation of the natural androgens, is mainly catalyzed by UGTs of subfamilies 2A and 2B. Nevertheless, the glucuronidation of ent-etiocholanolone and ent-androsterone by both UGT2B7 and UGT2B17 differs considerably from their respective activity toward the corresponding endogenous androgens, whereas UGT2A1-catalyzed conjugation is much less affected by the stereochemistry differences. Kinetic analyses reveal that the K(m) value of UGT2A1 for ent-estradiol is much higher than the corresponding value in the other two high activity enzymes, UGT1A10 and UGT2B7. Taken together, the results highlight large enantioselectivity differences between individual UGTs, particularly those of subfamily 2B.
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Affiliation(s)
- Nina Sneitz
- Centre for Drug Research, Faculty of Pharmacy, University of Helsinki, Finland
- Division of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Helsinki, Finland
| | - Kathiresan Krishnan
- Department of Developmental Biology, Washington University in St. Louis, School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, 63110, USA
| | - Douglas F. Covey
- Department of Developmental Biology, Washington University in St. Louis, School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri, 63110, USA
| | - Moshe Finel
- Centre for Drug Research, Faculty of Pharmacy, University of Helsinki, Finland
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69
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James MO. Steroid catabolism in marine and freshwater fish. J Steroid Biochem Mol Biol 2011; 127:167-75. [PMID: 20955793 DOI: 10.1016/j.jsbmb.2010.10.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2010] [Revised: 10/01/2010] [Accepted: 10/11/2010] [Indexed: 12/20/2022]
Abstract
Steroids play important roles in regulating many physiological functions in marine and freshwater fish. Levels of active steroid in blood and tissues are determined by the balance between synthetic and catabolic processes. This review examines what is known about pathways of catabolism of steroids, primarily sex steroids, in marine and freshwater fish. Cytochrome P450 (P450) isoforms present in hepatic microsomes catalyze steroid hydroxylation to metabolites with lower or no activity at estrogen or androgen receptors. Important pathways of steroid catabolism to readily excreted metabolites are glucuronidation and sulfonation of hydroxyl groups. Estradiol, testosterone, DHEA and hydroxylated metabolites of these and other steroids readily form glucuronide and sulfate conjugates in those fish species where these pathways have been examined. Little is known, however, of the structure and function of the UDP-glucuronosyltransferase (UGT) and sulfotransferase (SULT) enzymes involved in steroid conjugation in fish. Glucuronide and sulfate conjugates of steroids may be transported into and out of cells by organic anion transporter proteins and multi-drug resistance proteins, and there is growing evidence that these proteins play important roles in steroid conjugate transport and elimination. Induction or inhibition of any of these pathways by environmental chemicals can result in alteration of the natural balance of steroid hormones and could lead to disruption of the endocrine system. Recent studies in this area are presented, with particular focus on phase II (conjugative) pathways.
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Affiliation(s)
- Margaret O James
- Department of Medicinal Chemistry, University of Florida, PO Box 100485, 1600 SW Archer Road, Gainesville, FL 32610-0485, United States.
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70
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Wu B, Zhang S, Hu M. Evaluation of 3,3',4'-trihydroxyflavone and 3,6,4'-trihydroxyflavone (4'-O-glucuronidation) as the in vitro functional markers for hepatic UGT1A1. Mol Pharm 2011; 8:2379-89. [PMID: 21985641 DOI: 10.1021/mp200300w] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Identifying uridine 5'-diphospho-(UDP)-glucuronosyltransferase (UGT)-selective probes (substrates that are primarily glucuronidated by a single isoform) is complicated by the enzymes' large overlapping substrate specificity. Here, regioselective glucuronidation of two flavonoids, 3,3',4'-trihydroxyflavone (3,3',4'-THF) and 3,6,4'-trihydroxyflavone (3,6,4'-THF), is used to probe the activity of hepatic UGT1A1. The glucuronidation kinetics of 3,3',4'-THF and 3,6,4'-THF was determined using 12 recombinant human UGT isoforms and pooled human liver microsomes (pHLM). The individual contribution of main UGT isoforms to the metabolism of the two flavonoids in pHLM was estimated using the relative activity factor approach. UGT1A1 activity correlation analyses using flavonoids-4'-O-glucuronidation vs β-estradiol-3-glucuronidation (a well-recognized marker for UGT1A1) or vs SN-38 glucuronidation were performed using a bank of HLMs (n = 12) including three UGT1A1-genotyped HLMs (i.e., UGT1A1*1*1, UGT1A1*1*28, and UGT1A1*28*28). The results showed that UGT1A1 and 1A9, followed by 1A7, were the main isoforms for glucuronidating the two flavonoids, where UGT1A1 accounted for 92 ± 7% and 91 ± 10% of 4'-O-glucuronidation of 3,3',4'-THF and 3,6,4'-THF, respectively, and UGT1A9 accounted for most of the 3-O-glucuronidation. Highly significant correlations (R(2) > 0.944, p < 0.0001) between the rates of flavonoids 4'-O-glucuronidation and that of estradiol-3-glucuronidation or SN-38 glucuronidation were observed across 12 HLMs. In conclusion, UGT1A1-mediated 4'-O-glucuronidation of 3,3',4'-THF and 3,6,4'-THF was highly correlated with the glucuronidation of estradiol (3-OH) and SN-38. This study demonstrated for the first time that regioselective glucuronidation of flavonoids can be applied to probe hepatic UGT1A1 activity in vitro.
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Affiliation(s)
- Baojian Wu
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, 1441 Moursund Street, Houston, Texas 77030, United States
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71
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Fabregat A, Pozo OJ, Van Renterghem P, Van Eenoo P, Marcos J, Segura J, Ventura R. Detection of dihydrotestosterone gel, oral dehydroepiandrosterone, and testosterone gel misuse through the quantification of testosterone metabolites released after alkaline treatment. Drug Test Anal 2011; 3:828-35. [DOI: 10.1002/dta.351] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 07/29/2011] [Accepted: 07/29/2011] [Indexed: 12/26/2022]
Affiliation(s)
- Andreu Fabregat
- Bioanalysis Research Group; IMIM, Hospital del Mar; Doctor Aiguader 88; 08003; Barcelona; Spain
| | - Oscar J. Pozo
- Bioanalysis Research Group; IMIM, Hospital del Mar; Doctor Aiguader 88; 08003; Barcelona; Spain
| | - Pieter Van Renterghem
- Doping Control Laboratory (DoCoLab), Ugent; Departament of Clinical Chemistry, Microbiology and Immunology; Technologiepark 30; B-9052; Zwijnaarde; Belgium
| | - Peter Van Eenoo
- Doping Control Laboratory (DoCoLab), Ugent; Departament of Clinical Chemistry, Microbiology and Immunology; Technologiepark 30; B-9052; Zwijnaarde; Belgium
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72
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Anielski P, Simmchen J, Wassill L, Ganghofner D, Thieme D. Epidemiological investigation of the UGT2B17 polymorphism in doping control urine samples and its correlation to T/E ratios. Drug Test Anal 2011; 3:645-51. [PMID: 21928278 DOI: 10.1002/dta.332] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 06/22/2011] [Accepted: 06/27/2011] [Indexed: 11/12/2022]
Abstract
The deletion polymorphism of the enzyme UGT2B17 is known to correlate with the level of the testosterone to epitestosterone (T/E) ratio in urine specimen. Due to the importance of the T/E ratio to detect testosterone abuse in doping analysis, a PCR-ELISA system (Genotype® UGT test, AmplexDiagnostics) was established to identify the UGT2B17 phenotype in urine samples. Epidemiological investigations in a set of 674 routine doping controls (in- and out-of-competition) resulted in 22.8% homozygote gene-deleted and 74.5% UGT2B17-positive athletes. The validated test system has shown to be robust and sensitive: in only 18 cases (2.7%) isolation of cell material from urine failed. Following hydrolysis of glucuronidated conjugates, steroids were analyzed as bis-TMS derivatives by gas chromatography-mass spectrometry (GC-MS), for example, testosterone (T) and epitestosterone (E). Additionally, isotope ration mass spectrometry (IRMS) analysis and luteinizing hormone (LH) measurement were applied. Mean T/E ratios significantly correlated with the UGT2B17 phenotype (del: T/E 0.9; pos: 1.7), however the values did not differ as distinctive as reported in previous studies. Additionally, the T/E ratios in the gene-deleted group did not show a normal curve of distribution (median of T/E 0.5). Obviously, beside the UGT2B17 deletion further influences have to be taken into account, for example, polymorphisms or induction of other metabolizing enzymes. Our results indicate that the UGT2B17 polymorphism might be insufficient when utilized solely as a crucial parameter for individual interpretation of T/E in urine. Nevertheless, the detection of the UGT2B17-gene deletion in urine samples would provide additional information important for gathering evidence in analysis of steroids in doping control.
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Affiliation(s)
- Patricia Anielski
- Institute of Doping Analysis and Sports Biochemistry, Kreischa, Germany.
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73
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Bioavailability of testosterone enanthate dependent on genetic variation in the phosphodiesterase 7B but not on the uridine 5'-diphospho-glucuronosyltransferase (UGT2B17) gene. Pharmacogenet Genomics 2011; 21:325-32. [PMID: 21383644 DOI: 10.1097/fpc.0b013e328344c5c6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVE To study the disposition of serum testosterone and seven of its metabolites before and after 2 days of an intramuscular dose (500 mg) of testosterone enanthate in relation to the phosphodiesterase (PDE7B) and the uridine 5'-diphospho-glucuronosyltransferase (UGT2B17) genotypes. METHODS Patients were genotyped for UGT2B17 deletion polymorphism and single nucleotide polymorphisms in the PDE7B gene. The involvement of PDE7B in hydrolysis of enanthate was assessed in human liver homogenates. RESULTS Genetic variation in the PDE7B gene was found to be associated with the serum level of testosterone. Individuals homozygous for PDE7B rs7774640 G allele had a smaller increase (2.5-fold) in the serum testosterone levels compared with carriers of the A allele (3.9-fold, P=0.0006). In addition, genetic variation in the PDE7B gene significantly influences the testosterone/epitestosterone ratio, a biomarker of testosterone doping. Our in-vitro incubation studies confirmed that PDE7B serves as a catalyst of the hydrolysis of testosterone enanthate. The UGT2B17 deletion polymorphism did not show any significant association with serum testosterone levels or the other androgen metabolites investigated. CONCLUSION We have shown that PDE7B is involved in the hydrolysis of testosterone enanthate and that genetic variation in the PDE7B gene is a determinant of the systemic levels of testosterone after administration of testosterone enanthate. It is reasonable to believe that the genetic variation in testosterone bioavailability may be correlated to varying effects of this androgen, whether it is used for replacement therapy or abused in doping. Thus our results may be important to consider in doping test programmes and in therapeutics with androgens and other esterified drugs.
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74
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Kaivosaari S, Finel M, Koskinen M. N-glucuronidation of drugs and other xenobiotics by human and animal UDP-glucuronosyltransferases. Xenobiotica 2011; 41:652-69. [PMID: 21434773 DOI: 10.3109/00498254.2011.563327] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Metabolic disposition of drugs and other xenobiotics includes glucuronidation reactions that are catalyzed by the uridine diphosphate glucuronosyltransferases (UGTs). The most common glucuronidation reactions are O- and N-glucuronidation and in this review, we discuss both, while the emphasis is on N-glucuronidation. Interspecies difference in glucuronidation is another central issue in this review due to its importance in drug development. Accordingly, the available data on glucuronidation in different animals comes mainly from the species that are used in preclinical studies to assess the safety of drugs under development. Both O- and N-glucuronidation reactions are chemically diverse. Different O-glucuronidation reactions are described and discussed, and many drugs that undergo such reactions are indicated. The compounds that undergo N-glucuronidation include primary aromatic amines, hydroxylamines, amides, tertiary aliphatic amines, and aromatic N-heterocycles. The interspecies variability in N-glucuronidation is particularly high, above all when it comes to aliphatic tertiary amines and aromatic N-heterocycles. The N-glucuronidation rates in humans are typically much higher than in animals, largely due to the activity of two enzymes, the extensively studied UGT1A4, and the more recently identified as a main player in N-glucuronidation, UGT2B10. We discuss both enzymes and review the findings that revealed the role of UGT2B10 in N-glucuronidation.
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Affiliation(s)
- Sanna Kaivosaari
- Research and Development, Orion Corporation Orion Pharma, Espoo, Finland
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75
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Bushey RT, Chen G, Blevins-Primeau AS, Krzeminski J, Amin S, Lazarus P. Characterization of UDP-glucuronosyltransferase 2A1 (UGT2A1) variants and their potential role in tobacco carcinogenesis. Pharmacogenet Genomics 2011; 21:55-65. [PMID: 21164388 PMCID: PMC3019304 DOI: 10.1097/fpc.0b013e328341db05] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To examine UGT2A1 expression in human tissues, determine its glucuronidation activity against tobacco carcinogens, and assess the potential functional role of UGT2A1 missense single nucleotide polymorphisms on UGT2A1 enzyme activity. METHODS Reverse transcription polymerase chain reaction and real time polymerase chain reaction were used to assess UGT2A1 gene expression in various human tissues. A glucuronidation assay measured by reverse phase ultra-performance liquid chromatography was used to determine UGT2A1 activity. RESULTS UGT2A1 was expressed in aerodigestive tract tissues including trachea, larynx, tonsil, lung, and colon; no expression was observed in breast, whole brain, pancreas, prostate, kidney, liver, or esophagus. UGT2A1 exhibited highest expression in the lung, followed by trachea >tonsil >larynx >colon >olfactory tissue. Cell homogenates prepared from wildtype UGT2A1(75Lys308Gly) overexpressing HEK293 cells showed significant glucuronidation activity against a variety of polycyclic aromatic hydrocarbons including, 1-hydroxy-benzo(a)pyrene, benzo(a)pyrene-7,8-diol, and 5-methylchrysene-1,2-diol. No activity was observed in UGT2A1 overexpressing cell homogenate against substrates that form N-glucuronides, such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), nicotine, or N-OH-2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (N-OH PhIP). A significant (P<0.05) decrease (approximately 25%) in glucuronidation activity (Vmax/KM) was observed against all polycyclic aromatic hydrocarbons substrates for the UGT2A1(75Lys308Gly) variant compared with homogenates from wildtype UGT2A1(75Lys308Gly); no activity was observed for cell homogenates overexpressing the UGT2A1 variant for all substrates tested. CONCLUSION These data suggest that UGT2A1 is an important detoxification enzyme in the metabolism of polycyclic aromatic hydrocarbons within target tissues for tobacco carcinogens and functional polymorphisms in UGT2A1 may play a role in tobacco-related cancer risk.
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Affiliation(s)
- Ryan T. Bushey
- Molecular Epidemiology and Cancer Control Program, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Pharmacology, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Gang Chen
- Molecular Epidemiology and Cancer Control Program, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Public Health Sciences, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Andrea S. Blevins-Primeau
- Molecular Epidemiology and Cancer Control Program, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Pharmacology, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Jacek Krzeminski
- Chemical Carcinogenesis and Chemoprevention Program, Penn State Cancer Institute, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Pharmacology, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Shantu Amin
- Chemical Carcinogenesis and Chemoprevention Program, Penn State Cancer Institute, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Pharmacology, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Philip Lazarus
- Molecular Epidemiology and Cancer Control Program, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Pharmacology, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Department of Public Health Sciences, Penn State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
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76
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Thevis M, Kuuranne T, Geyer H, Schänzer W. Annual banned-substance review: analytical approaches in human sports drug testing. Drug Test Anal 2011; 3:1-14. [DOI: 10.1002/dta.245] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Accepted: 11/19/2010] [Indexed: 12/13/2022]
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77
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Zhang H, Tolonen A, Rousu T, Hirvonen J, Finel M. Effects of cell differentiation and assay conditions on the UDP-glucuronosyltransferase activity in Caco-2 cells. Drug Metab Dispos 2010; 39:456-64. [PMID: 21098645 DOI: 10.1124/dmd.110.036582] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cell differentiation increases UDP-glucuronosyltransferase (UGT) gene expression in Caco-2 cells. Glucuronidation of 13 UGT substrates, 1-naphthol, diclofenac, epitestosterone, estradiol, ethinylestradiol, indomethacin, oxazepam, R- and S-propranolol, propofol, testosterone, trifluoperazine, and zidovudine, were studied to derive a broad view on the effect of cell differentiation on the glucuronidation activities of different human UGTs. In parallel, the glucuronidation of these compounds in human liver microsomes (HLM) and human intestinal microsomes (HIM) was analyzed. Because many of the substrates are highly lipophilic, the effects of dimethyl sulfoxide (DMSO) concentrations in the reaction mixture on glucuronidation rates were tested, as well as the effect of alamethicin, a pore-forming peptide. Large differences were observed in the effects of DMSO and alamethicin between recombinant UGTs and Caco-2 cells and HLM and HIM, and, therefore, the activity assays were performed under multiple conditions. Regardless of the assay conditions, however, the results clearly indicated that although differentiation increases glucuronidation activity, the rates in Caco-2 cells are mostly very low, much lower than those in either HLM or HIM. One clear exception was observed: substrates of UGT1A6, such as 1-naphthol, were glucuronidated at very high rates in both undifferentiated and differentiated Caco-2 cells. It may thus be concluded that Caco-2 cells, even differentiated ones, do not provide a good model system to assess first-pass drug glucuronidation in the intestine.
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Affiliation(s)
- Hongbo Zhang
- Centre for Drug Research, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
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78
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Nicolich RS, Padilha MC, de Aquino Neto FR. Study of the endogenous steroid profile of male athletes from the Brazilian National Soccer Championship 2009. Drug Test Anal 2010; 2:599-602. [DOI: 10.1002/dta.214] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2010] [Revised: 09/25/2010] [Accepted: 09/25/2010] [Indexed: 11/10/2022]
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79
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Hirata H, Hinoda Y, Zaman MS, Chen Y, Ueno K, Majid S, Tripsas C, Rubin M, Chen LM, Dahiya R. Function of UDP-glucuronosyltransferase 2B17 (UGT2B17) is involved in endometrial cancer. Carcinogenesis 2010; 31:1620-6. [PMID: 20554747 DOI: 10.1093/carcin/bgq124] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Endometrial cancer (EC) is a steroid hormone-dependent cancer. Uridine 5'-diphospho-glucuronosyltransferase enzymes conjugate and detoxify endogenous and exogenous steroid hormones and environmental carcinogens. Among these enzymes, the function of UGT2B17 is unknown except for glucuronidation. The messenger RNA expression of UGT2B17 and myeloid cell leukemia-1 (Mcl-1) was significantly increased in EC tissues compared with matched normal endometrial tissues. Therefore, we focused on the function of UGT2B17 in EC. A total of nine patients with confirmed EC were enrolled in this study to investigate the expression of UGT2B17 and target genes. EC cell lines were used for functional tests including cell growth, invasion, apoptosis and cell cycle analyses. To find the target genes of UGT2B17, we performed microarray analysis to see which genes were upregulated or downregulated by UGT2B17-transfected cells. Functional analysis showed decreased numbers of viable cells and increased numbers of apoptotic cells in si-UGT2B17-transfected Ishikawa cells. Among microarray target genes, Mcl-1 was significantly downregulated in si-UGT2B17-transfected cells. We also found upregulation of Puma protein, a target of Mcl-1, in si-UGT2B17-transfected cells. This is the first report to show that UGT2B17 and Mcl-1 expression are upregulated in EC tissues and that UGT2B17 depletion induces inhibition of cell growth and apoptosis in EC cells through Mcl-1 downregulation.
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Affiliation(s)
- Hiroshi Hirata
- Department of Urology, Veterans Affairs Medical Center and University of California at San Francisco, 4150 Clement Street, San Francisco, CA 94121, USA
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80
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Current Opinion in Endocrinology, Diabetes & Obesity. Current world literature. Curr Opin Endocrinol Diabetes Obes 2010; 17:293-312. [PMID: 20418721 DOI: 10.1097/med.0b013e328339f31e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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81
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Heydel JM, Holsztynska EJ, Legendre A, Thiebaud N, Artur Y, Le Bon AM. UDP-glucuronosyltransferases (UGTs) in neuro-olfactory tissues: expression, regulation, and function. Drug Metab Rev 2010; 42:74-97. [PMID: 20067364 DOI: 10.3109/03602530903208363] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This work aims to review uridine diphosphate (UDP)-glucuronosyltransferase (UGT) expression and activities along different neuronal structures involved in the common physiological process of olfaction: olfactory epithelium, olfactory bulb, and olfactory cortex. For the first time, using high-throughput in situ hybridization data generated by the Allen Brain Atlas (ABA), we present quantitative analysis of spatial distribution of UGT genes in the mouse brain. The olfactory area is a central nervous system site with the highest expression of UGTs, including UGT isoforms not previously identified in the brain. Since there is evidence of the transfer of xenobiotics to the brain through the nasal pathway, circumventing the blood-brain barrier, olfactory UGTs doubtlessly share the common function of detoxification, but they are also involved in the metabolism and turnover of exogenous or endogenous compounds critical for physiological olfactory processing in these tissues. The function of olfactory UGTs will be discussed with a special focus on their participation in the perireceptor events involved in the modulation of olfactory perception.
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82
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Annual banned-substance review: analytical approaches in human sports drug testing. Drug Test Anal 2010; 2:149-61. [DOI: 10.1002/dta.128] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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83
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Schulze JJ, Rane A, Ekström L. Genetic variation in androgen disposition: implications in clinical medicine including testosterone abuse. Expert Opin Drug Metab Toxicol 2010; 5:731-44. [PMID: 19442030 DOI: 10.1517/17425250902976862] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Testosterone replacement therapy in hypogonadal men has been used for > 60 years. The use of testosterone substitution is continuously growing and is given to aging men to improve the quality of life. Because testosterone use is associated with muscle strength enhancing effects, it has become a popular drug to abuse. Doping with anabolic steroids, such as testosterone, is a severe challenge to the vision, moral and ethics in sports and has also become a significant and increasing problem in society. OBJECTIVE The primary aim of this review is to summarize and discuss the contribution of genetic components to inter-individual variation in androgen disposition. CONCLUSION Genetic variation has a large impact on androgen disposition. This variation is of the utmost importance for the interpretation of doping test results and may modulate the effects of testosterone replacement therapy and testosterone doping.
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Affiliation(s)
- Jenny J Schulze
- Karolinska Institutet, Division of Clinical Pharmacology, Stockholm, Sweden
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84
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Sottas PE, Saugy M, Saudan C. Endogenous steroid profiling in the athlete biological passport. Endocrinol Metab Clin North Am 2010; 39:59-73, viii-ix. [PMID: 20122450 DOI: 10.1016/j.ecl.2009.11.003] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The Athlete Biological Passport (ABP) is an individual electronic document that collects data regarding a specific athlete that is useful in differentiating between natural physiologic variations of selected biomarkers and deviations caused by artificial manipulations. A subsidiary of the endocrine module of the ABP, that which here is called Athlete Steroidal Passport (ASP), collects data on markers of an altered metabolism of endogenous steroidal hormones measured in urine samples. The ASP aims to identify not only doping with anabolic-androgenic steroids, but also most indirect steroid doping strategies such as doping with estrogen receptor antagonists and aromatase inhibitors. Development of specific markers of steroid doping, use of the athlete's previous measurements to define individual limits, with the athlete becoming his or her own reference, the inclusion of heterogeneous factors such as the UDPglucuronosyltransferase B17 genotype of the athlete, the knowledge of potentially confounding effects such as heavy alcohol consumption, the development of an external quality control system to control analytical uncertainty, and finally the use of Bayesian inferential methods to evaluate the value of indirect evidence have made the ASP a valuable alternative to deter steroid doping in elite sports. The ASP can be used to target athletes for gas chromatography/combustion/ isotope ratio mass spectrometry (GC/C/IRMS) testing, to withdraw temporarily the athlete from competing when an abnormality has been detected, and ultimately to lead to an antidoping infraction if that abnormality cannot be explained by a medical condition. Although the ASP has been developed primarily to ensure fairness in elite sports, its application in endocrinology for clinical purposes is straightforward in an evidence-based medicine paradigm.
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Affiliation(s)
- Pierre-Edouard Sottas
- Swiss Laboratory for Doping Analyses, University Center of Legal Medicine, West Switzerland, Epalinges, Switzerland.
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85
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Abstract
Phase-II metabolism has a major contribution to androgen metabolism, converting the highly non-polar compounds to a more easily excreted form prior to their excretion in urine. In the human body the main phase-II metabolic reactions are glucuronidation and sulphonation. These reactions are catalysed by enzymes, which are categorised into families and further subfamilies based on their function and similarities of their amino-acid sequences. Due to inter-individual variation of the metabolising enzymes and their activities, the metabolic patterns of prohibited substances should be estimated for efficient doping control. In addition to target analytes the phase-II reactions have an effect on the selection of sample preparation procedure, chromatographic technique and ionisation method of the analysis routine. For method development and identification purposes adequate reference material is required, and to replace the laborious in vivo excretion studies, in vitro methodologies have been implemented to produce intact phase-II metabolites of androgens.
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Affiliation(s)
- Tiia Kuuranne
- Doping Control Laboratory, United Laboratories Ltd, Höyläämötie 14, 00380, Helsinki, Finland.
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86
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Drăgan CA, Buchheit D, Bischoff D, Ebner T, Bureik M. Glucuronide Production by Whole-Cell Biotransformation Using Genetically Engineered Fission Yeast Schizosaccharomyces pombe. Drug Metab Dispos 2009; 38:509-15. [DOI: 10.1124/dmd.109.030965] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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87
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Sten T, Finel M, Ask B, Rane A, Ekström L. Non-steroidal anti-inflammatory drugs interact with testosterone glucuronidation. Steroids 2009; 74:971-7. [PMID: 19643121 DOI: 10.1016/j.steroids.2009.07.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 07/20/2009] [Accepted: 07/20/2009] [Indexed: 10/20/2022]
Abstract
Testosterone and epitestosterone are secreted mainly as glucuronide metabolites and the urinary ratio of testosterone glucuronide to epitestosterone glucuronide, often called T/E, serves as a marker for possible anabolic steroids abuse by athletes. UDP-glucuronosyltransferase (UGT) 2B17 is the most important catalyst of testosterone glucuronidation. The T/E might be affected by drugs that interact with UGT2B17, or other enzymes that contribute to testosterone glucuronidation. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used by sportsmen and we have examined the effect of two NSAIDs, diclofenac and ibuprofen, on testosterone and epitestosterone glucuronidation in human liver microsomes. In parallel, we have studied the inhibitory effect of these NSAIDs on recombinant UGT2B17 and UGT2B15, as well as other human hepatic UGTs that revealed low but detectable testosterone glucuronidation activity, namely UGT1A3, UGT1A4, UGT1A9 and UGT2B7. Both diclofenac and ibuprofen inhibited testosterone glucuronidation in microsomes, as well as UGT2B15 and UGT2B17. Interestingly, UGT2B15 was more sensitive than UGT2B17 to the two drugs, particularly to ibuprofen. Human liver microsomes lacking functional UGT2B17 exhibited significantly higher sensitivity to ibuprofen, suggesting that UGT2B15 plays a major role in the residual testosterone glucuronidation activity in UGT2B17-deficient individuals. Nonetheless, a minor contribution of other UGTs, particularly UGT1A9, to testosterone glucuronidation in such individuals cannot be ruled out at this stage. The epitestosterone glucuronidation activity of human liver microsomes was largely insensitive to ibuprofen and diclofenac. Taken together, the results highlight potential interactions between NSAIDs and androgen glucuronidation with possible implications for the validity of doping tests.
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Affiliation(s)
- Taina Sten
- Division of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Helsinki, FI-00014 Helsinki, Finland
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88
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Wong YC, Zhang L, Lin G, Zuo Z. Structure–activity relationships of the glucuronidation of flavonoids by human glucuronosyltransferases. Expert Opin Drug Metab Toxicol 2009; 5:1399-419. [DOI: 10.1517/17425250903179300] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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89
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Sten T, Kurkela M, Kuuranne T, Leinonen A, Finel M. UDP-Glucuronosyltransferases in Conjugation of 5α- and 5β-Androstane Steroids. Drug Metab Dispos 2009; 37:2221-7. [DOI: 10.1124/dmd.109.029231] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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