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Iannella L, Colamonici C, Curcio D, Botrè F, de la Torre X. Detecting the abuse of 19-norsteroids in doping controls: A new gas chromatography coupled to isotope ratio mass spectrometry method for the analysis of 19-norandrosterone and 19-noretiocholanolone. Drug Test Anal 2020; 13:770-784. [PMID: 33242373 DOI: 10.1002/dta.2985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 11/06/2022]
Abstract
The detection of 19-norsteroids abuse in doping controls currently relies on the determination of 19-norandrosterone (19-NA) by gas chromatography-tandem mass spectrometry (GC-MS/MS). An additional confirmatory analysis by gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS) is performed on samples showing 19-NA concentrations between 2.5 and 15 ng/ml and not originated from pregnant female athletes or female treated with 19-norethisterone. 19-Noretiocholanolone (19-NE) is typically produced to a lesser extent as a secondary metabolite. The aim of this work was to improve the GC-C-IRMS confirmation procedure for the detection of 19-norsteroids misuse. Both 19-NA and 19-NE were analyzed as target compounds (TCs), whereas androsterone (A), pregnanediol (PD), and pregnanetriol (PT) were selected as endogenous reference compounds (ERCs). The method was validated and applied to urine samples collected by three male volunteers after the administration of nandrolone-based formulations. Before the instrumental analysis, urine samples (<25 ml) were hydrolyzed with β-glucuronidase from Escherichia coli and extracted with n-pentane. Compounds of interest were purified through a single (for PT) or double (for 19-NE, 19-NA, A, and PD) liquid chromatographic step, to reduce the background noise and eliminate interferences that could have affect the accuracy of δ13 C values. The limit of quantification (LOQ) of 2 ng/ml was ensured for both 19-NA and 19-NE. The 19-NE determination could be helpful in case of "unstable" urine samples, in late excretion phases or when coadministration with 5α-reductase inhibitors occur.
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Affiliation(s)
- Loredana Iannella
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Rome, Italy.,Dipartimento di Chimica e Tecnologia del Farmaco, "Sapienza" Università di Roma, Rome, Italy
| | | | - Davide Curcio
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Rome, Italy
| | - Francesco Botrè
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Rome, Italy.,ISSUL-Institute des sciences du sport, Université de Lausanne, Lausanne, Switzerland
| | - Xavier de la Torre
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Rome, Italy
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2
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Meamar R, Maracy M, Nematollahi S, Yeroshalmi S, Zamani-Moghaddam A, Ghazvini MRA. Effect of taking dietary supplement on hematological and biochemical parameters in male bodybuilders an equation model. IRANIAN JOURNAL OF NURSING AND MIDWIFERY RESEARCH 2016; 20:681-8. [PMID: 26793253 PMCID: PMC4700687 DOI: 10.4103/1735-9066.170004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Background: The improved physical action following administration of supplements to bodybuilders was supported by changes in laboratory parameters. Despite the fact that these supplements are sometimes associated both advantage and side effects, this study were conducted for the purpose of evaluating the possible effects of some commonly used supplements in bodybuilders on the hematological and biochemical parameters. Materials and Methods: In this study, we included 40 male bodybuilders as cases and 40 controls in the age group of 20-40 years. They used different kinds of supplements for 1 year. In general, all the supplements used were classified into two groups: hormonal and non-hormonal. Laboratory tests were requested for evaluation of hematological and biochemical parameters. Results: In an equation model, we found that weight (P = 0.024), duration of bodybuilding (P < 0.001), and duration of hormone supplement consumption (P < 0.001) were loaded significantly on the latent variables, demographic and dietary supplement, respectively. The relationship between dietary supplement and biochemical and hematological parameters was significant (P = 0.01) and some of these parameters including creatinine (P = 0.023), blood aspartate aminotransferase (AST) (P < 0.001), alanine aminotransferase (ALT) (P < 0.001), and red blood cell distribution (RDW) (P = 0.046) had a significant role than others. In a multivariate regression model, we found that WBC (P < 0.001), platelets (P < 0.001), blood urea nitrogen (BUN; P < 0.001), creatinine (P < 0.001), AST (P = 0.005), and ALT (P = 0.001) were higher in athletes than in controls. Conclusions: It is strongly advised that there should be some concerns about possible supplement-induced changes in the laboratory exams for bodybuilders. The available supplements are unchecked and not approved by the US Food and Drug Administration (FDA). More studies should be designed for a better and precise administration of each supplement in athletes.
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Affiliation(s)
- Rokhsareh Meamar
- Department of Medical Science, School of Medicine, Najafabad Branch, Islamic Azad University and Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Maracy
- Department of Biostatistics and Epidemiology, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shahrzad Nematollahi
- Department of Biostatistics and Epidemiology, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shemouil Yeroshalmi
- Department of Medical Sciences, Najafabad Branch, Islamic Azad University, Isfahan, Iran
| | - Ali Zamani-Moghaddam
- Sayyd-Al-Shohada Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Reza Aghaye Ghazvini
- Isfahan Center of Health Research, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran
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Timcheh-Hariri A, Balali-Mood M, Aryan E, Sadeghi M, Riahi-Zanjani B. Toxic hepatitis in a group of 20 male body-builders taking dietary supplements. Food Chem Toxicol 2012; 50:3826-32. [PMID: 22809474 DOI: 10.1016/j.fct.2012.07.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 06/23/2012] [Accepted: 07/06/2012] [Indexed: 01/01/2023]
Abstract
Dietary supplements have been used for decades for enhancing muscle growth. The harm caused by some of these products is well documented. We investigated and reported toxic hepatitis in 20 male athletes following self-prescribing of a number of dietary supplements which are lesser known. The patients' ages ranged from 24 to 32 with a mean of 28 years. They had taken three kinds of supplements for 1 year including testosterone optimizer agent T Bomb II, a creatine supplement Phosphagen and an amino acid based supplement Cell-Tech. Based on the history, clinical examination, and laboratory findings the cases were diagnosed as toxic hepatitis. After discontinuation of taking the supplements, clinical recovery and improvement of liver function tests were achieved within 30 days. Causality assessment with the CIOMS (Council for International Organization Medical Sciences) scale showed a "possible" grade of causality (+5 points) for these supplements. It can be concluded that these newer anabolic supplements may induce toxic hepatitis. Since the health risks of them may be severe, the use of these kinds of dietary supplements should be discouraged.
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Affiliation(s)
- Alireza Timcheh-Hariri
- Medical Toxicology Research Center, School of Medicine, Mashhad University of Medical Sciences, and Department of Clinical Bacteriology, Ghaem University Hospital, Mashhad, Iran
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Abstract
Nandrolone or nortestosterone, an anabolic-androgenic steroid, has been prohibited by doping control regulations for more than 30 years. Although its main metabolism in the human body was already known at that time, and detection of its misuse by gas or liquid chromatographic separation with mass spectrometric detection is straightforward, many interesting aspects regarding this doping agent have appeared since.Over the years, nandrolone preparations have kept their position among the prohibited substances that are most frequently detected in WADA-accredited laboratories. Their forms of application range from injectable fatty acid esters to orally administered nandrolone prohormones. The long detection window for nandrolone ester preparations and the appearance of orally available nandrolone precursors have changed the pattern of misuse.At the same time, more refined analytical methods with lowered detection limits led to new insights into the pharmacology of nandrolone and revelation of its natural production in the body.Possible contamination of nutritional supplements with nandrolone precursors, interference of nandrolone metabolism by other drugs and rarely occurring critical changes during storage of urine samples have to be taken into consideration when interpreting an analytical finding.A set of strict identification criteria, including a threshold limit, is applied to judge correctly an analytical finding of nandrolone metabolites. The possible influence of interfering drugs, urine storage or natural production is taken into account by applying appropriate rules and regulations.
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Affiliation(s)
- Peter Hemmersbach
- Norwegian Doping Control Laboratory, Oslo University Hospital, NO-0514, Oslo, Norway.
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5
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Anabolic and androgenic activity of 19-norandrostenedione after oral and subcutaneous administration--analysis of side effects and metabolism. Toxicol Lett 2009; 188:137-41. [PMID: 19446246 DOI: 10.1016/j.toxlet.2009.03.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 03/23/2009] [Accepted: 03/25/2009] [Indexed: 11/20/2022]
Abstract
One of the most frequently misused steroid precursors (prohormones) is 19-norandrostenedione (estr-4-ene-3,17-dione, NOR). Recently we have show that NOR stimulates skeletal muscle growth after s.c. administration in a highly selective manner but exhibits only weak androgenic activity in rats. Because most abusers take NOR orally, the aim of this study was to compare the anabolic and androgenic potency of NOR between s.c. and oral application. Orchiectomised rats were treated with NOR either s.c. (1 mg/kg BW/day) or orally (0.1, 1 and 10 mg/kg BW/day). The tissue weights of the levator ani, the seminal vesicle and the prostate were analysed to determine the anabolic and androgenic activity. Heart and liver wet weights were examined to identify side effects. Serum concentrations of NOR and its metabolite nandrolone (NT) were determined. GCMC analysis revealed that free and glucuronidated NOR and NT were detectable in the serum after oral and s.c. administration and that NOR was converted to NT in comparable amounts independent of the route of administration. In agreement to our previous study s.c. application of NOR stimulates skeletal muscle growth but has only weak androgenic effects. In contrast, after oral administration of NOR neither stimulation of the prostate nor the levator ani could be observed in the doses administered in this study. Interestingly, and in contrast to s.c. treatment, oral administration of NOR resulted in a dose-dependent decrease of body weight. In summary, oral administration of NOR, at least in the rat, seems to be a very ineffective strategy for stimulating skeletal muscle mass increases but may be associated with side effects.
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Urban NH, Chamberlin B, Ramage S, Roberts Z, Loria RM, Beckman MJ. Effects of alpha/beta-androstenediol immune regulating hormones on bone remodeling and apoptosis in osteoblasts. J Steroid Biochem Mol Biol 2008; 110:223-9. [PMID: 18513951 DOI: 10.1016/j.jsbmb.2008.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Indexed: 01/26/2023]
Abstract
A large body of evidence suggests that the immune system directly impacts bone physiology. We tested whether immune regulating hormones (IRH), 17beta-androstenediol (beta-AED), 7beta,17beta-androstenetriol (beta-AET) or the 17alpha-androstenediol (alpha-AED), and 7alpha,17beta-androstenetriol (alpha-AET) metabolites could directly influence bone remodeling in vitro using human fetal osteoblasts (FOB-9). The impact on bone remodeling was examined by comparing the ratio of RANKL/OPG gene expression in response to AED and AET compounds. The alpha-AED was found to significantly increase in the ratio of RANKL/OPG gene expression and altering the morphology of RANKL stained FOB-9 cells. Cell viability was assessed using a Live/Dead assay. Again alpha-AED was unique in its ability to reduce the proportion of viable cells, and to induce mild apoptosis of FOB-9 cells. Treatment of FOB-9 cells with WY14643, an activator of PPAR-alpha and -gamma, also significantly elevated the percentage of dead cells. This increase was abolished by co-treatment with GW9962, a specific inhibitor of PPAR-gamma. Analysis of PPAR-gamma mRNA by Quantitative RT-PCR and its activation by DNA binding demonstrated that alpha-AED increased PPAR-gamma activation by 19%, while beta-AED conferred a 37% decrease in PPAR-gamma activation. In conclusion, alpha-AED opposed beta-AED by elevating a bone resorption scenario in osteoblast cells. The increase in RANKL/OPG is modulated by an activation of PPAR-gamma that in turn caused mild apoptosis of FOB-9 cells.
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Affiliation(s)
- Nicole H Urban
- Department of Orthopaedic Surgery, Virginia Commonwealth University School of Medicine, Richmond, VA 23298-0694, USA
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Diel P, Friedel A, Geyer H, Kamber M, Laudenbach-Leschowsky U, Schänzer W, Schleipen B, Thevis M, Vollmer G, Zierau O. The prohormone 19-norandrostenedione displays selective androgen receptor modulator (SARM) like properties after subcutaneous administration. Toxicol Lett 2008; 177:198-204. [DOI: 10.1016/j.toxlet.2008.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Revised: 01/20/2008] [Accepted: 01/21/2008] [Indexed: 11/26/2022]
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Martello S, Felli M, Chiarotti M. Survey of nutritional supplements for selected illegal anabolic steroids and ephedrine using LC-MS/MS and GC-MS methods, respectively. ACTA ACUST UNITED AC 2007; 24:258-65. [PMID: 17364927 DOI: 10.1080/02652030601013729] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Several studies have highlighted that nutritional supplements may contain undeclared substances that are banned by the International Olympic Committee (IOC)/World Anti-Doping Agency (WADA). This paper describes a qualitative liquid chromatography coupled with tandem mass spectrometry detection (LC-MS/MS) method to detect anabolic androgenic steroids (4-androsten-3,17-dion, 4-oestren-3,17-dion, 5alpha-androsten-17beta-ol-3-one, boldenone, nandrolone, nandrolone decanoate, testosterone, and testosterone decanoate) and ephedrine in food supplements. The products are dissolved in methanol and analysed by gas chromatography-mass spectrometry (GC-MS). The methanolic solution was added to testosterone-d(3), evaporated to dryness, mixed with NaOH and extracted with n-pentane:diethylether (9:1). LC-MS/MS analyses were performed in selected reaction monitoring (SRM) on an ion-trap equipped with an atmospheric pressure chemical ionization (APCI) probe operating in positive-ion mode. The method was applied to 64 nutritional supplements. A total of 12.5% of the nutritional supplements analysed contained banned substances not declared on the label (anabolic steroids and ephedrine). Detection limits were in the range 1-25 ng g(-1).
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Affiliation(s)
- S Martello
- Università Cattolia del Sacro Cuore, Istituto Medicina Legale, L.go Francecso Vito, 1, Rome I-00168, Italy.
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9
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Abstract
The dietary supplements androstenedione, dehydroepiandrosterone, and androstenediol are precursors in the endogenous production of testosterone. The efficacy and safety of these prohormones are not well established but are promoted to have the same androgenic effects on building muscle mass and strength as anabolic-androgenic steroids. Studies have demonstrated repeatedly that acute and long-term administration of these oral testosterone precursors does not effectively increase serum testosterone levels and fails to produce any significant changes in lean body mass, muscle strength, or performance improvement compared with placebo. The Anabolic Steroid Control Act of 2004 lists androstenedione as a schedule III controlled substance, and it is regulated by the U.S. Food and Drug Administration. Testosterone precursors are banned by most major sports organizations.
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Affiliation(s)
- Troy M Smurawa
- Northeastern Ohio Universities College of Medicine, 4209 State Route 44, PO Box 95, Rootstown, OH 44272, USA.
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10
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Friedel A, Geyer H, Kamber M, Laudenbach-Leschowsky U, Schänzer W, Thevis M, Vollmer G, Zierau O, Diel P. 17beta-hydroxy-5alpha-androst-1-en-3-one (1-testosterone) is a potent androgen with anabolic properties. Toxicol Lett 2006; 165:149-55. [PMID: 16621347 DOI: 10.1016/j.toxlet.2006.03.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Revised: 03/07/2006] [Accepted: 03/10/2006] [Indexed: 11/30/2022]
Abstract
Since the begining of the year 2005, the use of steroid precursors (prohormones) is illegal in the United States; nevertheless, there is still an enormous abuse of such substances. One of the most frequently misused steroids, often declared to be a prohormone, is 1-testosterone (17beta-hydroxy-5alpha-androst-1-en-3-one, 1-Testo). In this study, we have characterised molecular mechanisms of its action, determined its tissue specific androgenic and anabolic potency and investigated potential adverse effects. 1-Testo binds highly selective to the androgen receptor (AR) and has a high potency to stimulate AR dependent transactivation. In vivo an equimolar dose of 1-Testo has the same potency to stimulate the growth of the prostate, the seminal vesicles and the androgen sensitive levator ani muscle as the reference compound testosterone propionate (TP). Administration of 1-Testo, in contrast to TP, results in a significant increase of liver weight. Our results demonstrate that 1-Testo, even without being metabolised, is a very potent androgen. It binds selectively to the AR and transactivates AR dependent reporter genes. In vivo it has a high androgenic and anabolic potency and increases liver weight. In summary 1-Testo can be characterised as a typical anabolic steroid. It has to be assumed that consumption of this substance is associated with adverse side effects typical for this class of compounds. Therefore, a strict control of its ban is essential.
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Affiliation(s)
- A Friedel
- Center for Preventive Doping Research, Institute of Cardiovascular Research and Sports Medicine, Department of Molecular and Cellular Sports Medicine, German Sport University Cologne, 50927 Cologne, Germany
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Baume N, Mahler N, Kamber M, Mangin P, Saugy M. Research of stimulants and anabolic steroids in dietary supplements. Scand J Med Sci Sports 2006; 16:41-8. [PMID: 16430680 DOI: 10.1111/j.1600-0838.2005.00442.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose of this study was to analyze the composition of 103 dietary supplements bought on the internet. The supplements were dispatched in four different categories according to their announced contents [creatine, prohormones, "mental enhancers" and branched chain amino acids (BCAA)]. All the supplements were screened for the presence of stimulants and main anabolic steroids parent compounds. At the same time, the research was focused on the precursors and metabolites of testosterone and nandrolone. The study pointed out three products containing an anabolic steroid, metandienone, in a very high amount. The ingestion of such products induced a high quantity of metandienone metabolites in urines that would be considered as a positive antidoping test. The results have also shown that one creatine product and three "mental enhancers" contained traces of hormones or prohormones not claimed on the labels and 14 prohormone products contained substances other than those indicated by the manufacturer. The oral intake of the creatine product revealed the presence of the two main nandrolone metabolites (19-norandrosterone and 19-noretiocholanolone) in urine.
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Affiliation(s)
- N Baume
- Laboratoire Suisse d'Analyse du Dopage, Institut Universitaire de Médecine Légale, Département Universitaire de Médecine et Santé Communautaire, Lausanne, Switzerland.
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Wiesenfeld PW, Sapienza PP, Flynn TJ, Ford CE, Ross IA, Sahu S, Kim CS, O'Donnell MW, Collins TFX, Sprando RL. Effects of oral androstenedione on phospholipid fatty acids, ATP, caspase-3, prostaglandin E(2) and C-reactive protein in serum and livers of pregnant and non-pregnant female rats. Food Chem Toxicol 2005; 44:579-87. [PMID: 16289525 DOI: 10.1016/j.fct.2005.09.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 09/12/2005] [Accepted: 09/25/2005] [Indexed: 11/23/2022]
Abstract
Androstenedione, a steroidal dietary supplement taken to enhance athletic performance, could affect serum and liver lipid metabolism, induce liver toxicity or alter inflammatory response depending on dose and duration of exposure. Pregnancy could further exaggerate these effects. To examine this, mature female rats were gavaged with 0, 5, 30 or 60 mg/kg/day androstenedione beginning two weeks prior to mating and continuing through gestation day 19. Non-pregnant female rats were gavaged over the same time frame with 0 or 60 mg/kg/day androstenedione. Serum was collected and livers were removed from dams on gestation day 20 and from non-pregnant rats after 5 weeks of treatment. Androstenedione had no effect on serum total cholesterol, triglycerides or HDL-cholesterol, but significantly decreased C-reactive protein in pregnant rats and prostaglandin E(2) in serum of both pregnant and non-pregnant rats. There were treatment related decreases in liver ATP and, to a lesser degree, caspase-3 and no change in alkaline phosphatase of pregnant female rats. Androstenedione decreased docosahexaenoic acid in both serum and liver phospholipids of pregnant female rats. In conclusion, oral androstenedione did not result in overt hepatotoxicity in pregnant female rats, but produced modest changes in lipid metabolism and may impair regeneration of injured hepatic cells or tissue.
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Affiliation(s)
- P W Wiesenfeld
- US FDA, Center for Food Safety and Applied Nutrition, Office of Applied Research and Safety Assessment, 8301 Muirkirk Road, Laurel, MD 20708, USA.
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Miller KKM, Cai J, Ripp SL, Pierce WM, Rushmore TH, Prough RA. Stereo- and regioselectivity account for the diversity of dehydroepiandrosterone (DHEA) metabolites produced by liver microsomal cytochromes P450. Drug Metab Dispos 2004; 32:305-13. [PMID: 14977864 DOI: 10.1124/dmd.32.3.305] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to quantify the oxidative metabolism of dehydroepiandrosterone (3beta-hydroxy-androst-5-ene-17-one; DHEA) by liver microsomal fractions from various species and identify the cytochrome P450 (P450) enzymes responsible for production of individual hydroxylated DHEA metabolites. A gas chromatography-mass spectrometry method was developed for identification and quantification of DHEA metabolites. 7alpha-Hydroxy-DHEA was the major oxidative metabolite formed by rat (4.6 nmol/min/mg), hamster (7.4 nmol/min/mg), and pig (0.70 nmol/min/mg) liver microsomal fractions. 16alpha-Hydroxy-DHEA was the next most prevalent metabolite formed by rat (2.6 nmol/min/mg), hamster (0.26 nmol/min/mg), and pig (0.16 nmol/min/mg). Several unidentified metabolites were formed by hamster liver microsomes, and androstenedione was produced only by pig microsomes. Liver microsomal fractions from one human demonstrated that DHEA was oxidatively metabolized at a total rate of 7.8 nmol/min/mg, forming 7alpha-hydroxy-DHEA, 16alpha-hydroxy-DHEA, and a previously unidentified hydroxylated metabolite, 7beta-hydroxy-DHEA. Other human microsomal fractions exhibited much lower rates of metabolism, but with similar metabolite profiles. Recombinant P450s were used to identify the cytochrome P450s responsible for DHEA metabolism in the rat and human. CYP3A4 and CYP3A5 were the cytochromes P450 responsible for production of 7alpha-hydroxy-DHEA, 7beta-hydroxy-DHEA, and 16alpha-hydroxy-DHEA in adult liver microsomes, whereas the fetal/neonatal form CYP3A7 produced 16alpha-hydroxy and 7beta-hydroxy-DHEA. CYP3A23 uniquely formed 7alpha-hydroxy-DHEA, whereas other P450s, CYP2B1, CYP2C11, and CYP2D1, were responsible for 16alpha-hydroxy-DHEA metabolite production in rat liver microsomal fractions. These results indicate that the stereo- and regioselectivity of hydroxylation by different P450s account for the diverse DHEA metabolites formed among various species.
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Affiliation(s)
- Kristy K Michael Miller
- Department of Biochemistry and Molecular Biology, The University of Louisville School of Medicine, Louisville, Kentucky 40292, USA
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