1
|
Shimada T, Takenaka S, Kakimoto K, Murayama N, Lim YR, Kim D, Foroozesh MK, Yamazaki H, Guengerich FP, Komori M. Structure-Function Studies of Naphthalene, Phenanthrene, Biphenyl, and Their Derivatives in Interaction with and Oxidation by Cytochromes P450 2A13 and 2A6. Chem Res Toxicol 2016; 29:1029-40. [PMID: 27137136 PMCID: PMC5293596 DOI: 10.1021/acs.chemrestox.6b00083] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Naphthalene, phenanthrene, biphenyl, and their derivatives having different ethynyl, propynyl, butynyl, and propargyl ether substitutions were examined for their interaction with and oxidation by cytochromes P450 (P450) 2A13 and 2A6. Spectral interaction studies suggested that most of these chemicals interacted with P450 2A13 to induce Type I binding spectra more readily than with P450 2A6. Among the various substituted derivatives examined, 2-ethynylnaphthalene, 2-naphthalene propargyl ether, 3-ethynylphenanthrene, and 4-biphenyl propargyl ether had larger ΔAmax/Ks values in inducing Type I binding spectra with P450 2A13 than their parent compounds. P450 2A13 was found to oxidize naphthalene, phenanthrene, and biphenyl to 1-naphthol, 9-hydroxyphenanthrene, and 2- and/or 4-hydroxybiphenyl, respectively, at much higher rates than P450 2A6. Other human P450 enzymes including P450s 1A1, 1A2, 1B1, 2C9, and 3A4 had lower rates of oxidation of naphthalene, phenanthrene, and biphenyl than P450s 2A13 and 2A6. Those alkynylated derivatives that strongly induced Type I binding spectra with P450s 2A13 and 2A6 were extensively oxidized by these enzymes upon analysis with HPLC. Molecular docking studies supported the hypothesis that ligand-interaction energies (U values) obtained with reported crystal structures of P450 2A13 and 2A6 bound to 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, indole, pilocarpine, nicotine, and coumarin are of use in understanding the basis of possible molecular interactions of these xenobiotic chemicals with the active sites of P450 2A13 and 2A6 enzymes. In fact, the ligand-interaction energies with P450 2A13 4EJG bound to these chemicals were found to relate to their induction of Type I binding spectra.
Collapse
Affiliation(s)
- Tsutomu Shimada
- Laboratory of Cellular and Molecular Biology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Orai-Kita, Izumisano, Osaka 598-8531, Japan
| | - Shigeo Takenaka
- Laboratory of Cellular and Molecular Biology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Orai-Kita, Izumisano, Osaka 598-8531, Japan
| | - Kensaku Kakimoto
- Department of Biological Sciences, Konkuk University, Seoul 143-701, Republic of Korea
| | - Norie Murayama
- Laboratory of Drug Metabolism and Pharmacokinetics, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | - Young-Ran Lim
- Department of Biological Sciences, Konkuk University, Seoul 143-701, Republic of Korea
| | - Donghak Kim
- Department of Biological Sciences, Konkuk University, Seoul 143-701, Republic of Korea
| | - Maryam K. Foroozesh
- Department of Chemistry, Xavier University of Louisiana, New Orleans, Louisiana 70125, United States
| | - Hiroshi Yamazaki
- Laboratory of Drug Metabolism and Pharmacokinetics, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | - F. Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
| | - Masayuki Komori
- Laboratory of Cellular and Molecular Biology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Orai-Kita, Izumisano, Osaka 598-8531, Japan
| |
Collapse
|
2
|
Boyland E, Chasseaud LF. The role of glutathione and glutathione S-transferases in mercapturic acid biosynthesis. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 32:173-219. [PMID: 4892500 DOI: 10.1002/9780470122778.ch5] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
3
|
Upadhyaya P, Rao P, Hochalter JB, Li ZZ, Villalta PW, Hecht SS. Quantitation of N-acetyl-S-(9,10-dihydro-9-hydroxy-10-phenanthryl)-L-cysteine in human urine: comparison with glutathione-S-transferase genotypes in smokers. Chem Res Toxicol 2006; 19:1234-40. [PMID: 16978029 PMCID: PMC2518842 DOI: 10.1021/tx060096w] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
There are major interindividual differences in carcinogenic polycyclic aromatic hydrocarbon (PAH) metabolism in humans, and it has been hypothesized that these differences may be related to cancer risk in smokers and other exposed people. One important pathway of PAH metabolism involves the detoxification of the epoxide and diol epoxide metabolites by reaction with glutathione, catalyzed by glutathione-S-transferases (GSTs). Interindividual differences in these pathways have been examined by genotyping methods, investigating polymorphisms in GSTM1 and GSTP1. We are developing a phenotyping approach to assessing individual differences in PAH metabolism by quantifying human urinary metabolites of the ubiquitous PAH phenanthrene (1). In this study, we developed a method for quantitation of a mercapturic acid, N-acetyl-S-(9,10-dihydro-9-hydroxy-10-phenanthryl)-l-cysteine (PheO-NAC, 12), the end product of the reaction of phenanthrene-9,10-epoxide (11) with glutathione. [D(10)]PheO-NAC was added to the urine as internal standard, and the PheO-NAC fraction was enriched by solid-phase extraction. PheO-NAC was quantified by liquid chromatography electrospray ionization tandem mass spectrometry with selected reaction monitoring. The detection limit was approximately 4 fmol/mL of urine. PheO-NAC was detected in the urine of 46 of 104 smokers, mean (S.D.) 57.9 +/- 144 fmol/mL. PheO-NAC was detected significantly more frequently (P < 0.0001) in subjects who were GSTM1 positive than in those who were GSTM1 null, and the levels of PheO-NAC were significantly higher in the GSTM1 positive subjects, consistent with a role for GSTM1 in the detoxification of phenanthrene-9,10-epoxide. There were no significant relationships between PheO-NAC levels and the occurrence of two GSTP1 polymorphisms. The results of this study provide the first evidence for a PAH-derived mercapturic acid in human urine and should be useful in the development of a phenotyping approach to assess individual differences in PAH metabolism.
Collapse
Affiliation(s)
- Pramod Upadhyaya
- The Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Priyanka Rao
- The Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | | | - Zhong-ze Li
- The Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | | | - Stephen S. Hecht
- The Cancer Center, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
4
|
Boyland E, Sims P. The metabolism of benz[a]anthracene and dibenz[a,h]anthracene and their 5,6-epoxy-5,6-dihydro derivatives by rat-liver homogenates. Biochem J 2006; 97:7-16. [PMID: 16749126 PMCID: PMC1264537 DOI: 10.1042/bj0970007] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
1. Benz[a]anthracene was hydroxylated by rat-liver homogenates on the 3,4-,5,6- or 8,9-bond to yield phenols and dihydrodihydroxy compounds. Metabolic action at the 7- and 12-positions was also detected. 5,6-Epoxy-5,6-dihydrobenzanthracene was converted into a phenol that is probably 5-hydroxybenzanthracene and 5,6-dihydro-5,6-dihydroxybenzanthracene. Both substrates yielded a product that is probably S-(5,6-dihydro-6-hydroxy-5-benzanthracenyl)glutathione. 2. Dibenz[a,h]anthracene was hydroxylated by rat-liver homogenates to yield products that are probably 3- and 4-hydroxydibenzanthracene, 1,2-dihydro-1,2-dihydroxydibenzanthracene, 3,4-dihydro-3,4-dihydroxydibenzanthracene and 5,6-dihydro-5,6-dihydroxydibenzanthracene. There was no evidence for metabolic action at the 7- and 14-positions. 5,6-Epoxy-5,6-dihydrodibenzanthracene was converted into a phenol that is probably 5-hydroxydibenzanthracene and 5,6-dihydro-5,6-dihydroxydibenzanthracene. Both substrates yielded a glutathione conjugate that is probably S-(5,6-dihydro-6-hydroxy-5-dibenzanthracenyl)glutathione. 3. The synthesis of 5,6-epoxy-5,6-dihydrodibenzanthracene is described and the reactions of this epoxide and 5,6-epoxy-5,6-dihydrobenzanthracene with water and thiols have been investigated. 4. The oxidation of dibenzanthracene in the ascorbic acid-Fe(2+) ion-oxygen model system is described.
Collapse
Affiliation(s)
- E Boyland
- Chester Beatty Research Institute, Institute of Cancer Research: Royal Cancer Hospital, London, S.W. 3
| | | |
Collapse
|
5
|
Rihs HP, Pesch B, Kappler M, Rabstein S, Rossbach B, Angerer J, Scherenberg M, Adams A, Wilhelm M, Seidel A, Brüning T. Occupational exposure to polycyclic aromatic hydrocarbons in German industries: association between exogenous exposure and urinary metabolites and its modulation by enzyme polymorphisms. Toxicol Lett 2005; 157:241-55. [PMID: 15917149 DOI: 10.1016/j.toxlet.2005.02.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2004] [Revised: 02/23/2005] [Accepted: 02/24/2005] [Indexed: 10/25/2022]
Abstract
A cross-sectional study was conducted in 170 German workers exposed to polycyclic aromatic hydrocarbons (PAH) to investigate the role of 11 polymorphisms of CYP1A1, CYP1A2, CYP1B1, CYP3A4, EPHX1, GSTM1, GSTT1, and GSTP1 in the association between occupational exposure to PAH and urinary PAH metabolites. Polymorphisms were genotyped with real-time PCR. Exposure to 16 PAH was measured by personal air sampling. Urinary concentrations of 1-hydroxypyrene (1-OHP) and the sum of 1-, 2+9-, 3-, and 4-hydroxyphenanthrenes (OHPhe) were determined post-shift. Urinary 1-OHP and OHPhe correlated significantly with exogenous pyrene (Spearman r=0.52, p<0.0001) and phenanthrene (Spearman r=0.72, p<0.0001), respectively. ANCOVA was applied to investigate potential predictors of the metabolite levels. Current smoking and type of industry turned out to be predictors of 1-OHP but not of OHPhe. CYP1A1 3801TC carriers showed 1.6-fold higher OHPhe levels than 3801TT carriers (p=0.03). EPHX1 113HH was associated with higher and 139RR with lower metabolite levels when compared with the corresponding reference genotypes (113YY; 139HH). In comparison to GSTP1 114AA, carriers of the V allele had 1.5-fold higher 1-OHP (p=0.03) and 2-fold higher OHPhe concentrations (p=0.001). OHPhe turned out to be also a suitable biomarker of occupational PAH exposure. The association with ambient PAH exposure and the influence of polymorphisms was more pronounced for OHPhe.
Collapse
Affiliation(s)
- Hans-Peter Rihs
- Berufsgenossenschaftliches Forschungsinstitut für Arbeitsmedizin (BGFA), Ruhr University of Bochum, Buerkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Jacob J, Seidel A. Biomonitoring of polycyclic aromatic hydrocarbons in human urine. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 778:31-47. [PMID: 12376115 DOI: 10.1016/s0378-4347(01)00467-4] [Citation(s) in RCA: 196] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Measurement of polycyclic aromatic hydrocarbons (PAH) metabolites in human urine is the method of choice to determine occupational and/or environmental exposure of an individual to PAH, in particular, when multiple routes of exposure have to be taken into account. Requirements for methods of biomonitoring PAH metabolites in urine are presented. Studies using 1-hydroxypyrene or phenanthrene metabolites including its phenols and dihydrodiols are summarized. The role of these PAH metabolites as established biomarkers and also more recent developments of PAH biomonitoring are discussed.
Collapse
Affiliation(s)
- Jürgen Jacob
- Biochemisches Institut für Umweltcarcinogene-Prof Dr Gernot Grimmer-Stiftung, Lurup 4, D-22927 Grosshansdorf, Germany.
| | | |
Collapse
|
7
|
BOYLAND E, SIMS P. Metabolism of polycyclic compounds. 21. The metabolism of phenanthrene in rabbits and rats: dihydrodihydroxy compounds and related glucosiduronic acids. Biochem J 1998; 84:571-82. [PMID: 13872198 PMCID: PMC1243716 DOI: 10.1042/bj0840571] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
8
|
SIMS P. Metabolism of polycyclic compounds. 19. The metabolism of phenanthrene in rabbits and rats: phenols and sulphuric esters. Biochem J 1998; 84:558-63. [PMID: 13913240 PMCID: PMC1243714 DOI: 10.1042/bj0840558] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
9
|
BOYLAND E, SIMS P. METABOLISM OF POLYCYCLIC COMPOUNDS. THE METABOLISM OF 9,10-EPOXY-9,10-DIHYDROPHENANTHRENE IN RATS. Biochem J 1996; 95:788-92. [PMID: 14342516 PMCID: PMC1206807 DOI: 10.1042/bj0950788] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
1. 9,10-Epoxy-9,10-dihydrophenanthrene is converted by rats into trans-9,10-dihydro-9,10-dihydroxyphenanthrene and its conjugates and into N-acetyl-S-(9,10-dihydro-9-hydroxy-10-phenanthryl)-l- cysteine. Small amounts of 9-phenanthryl sulphate and glucosiduronate are also formed, together with 9-hydroxy-10-phenanthryl sulphate. 2. The epoxide readily rearranges to 9-hydroxyphenanthrene and reacts with water to give the dihydrodihydroxy compound and with N-acetylcysteine to give the mercapturic acid. One of the diastereoisomeric forms of the methyl ester of the mercapturic acid is identical with the ester of the mercapturic acid excreted by rats dosed with the epoxide or by rats and rabbits dosed with phenanthrene. 3. A rat-liver homogenate converts the epoxide into trans-9,10-dihydrodihydroxyphenanthrene and S-(9,10-dihydro-9-hydroxy-10-phenanthryl)glutathione. The latter compound was not formed when boiled rat-liver homogenate was used, but was formed chemically from the epoxide and glutathione under more vigorous conditions. 4. The results provide further indications that the metabolism of aromatic hydrocarbons involves the intermediary formation of epoxides.
Collapse
|
10
|
Ouyang Z, Greenberg A, Kwei GY, Kauffman FC, Faria E. A Rapid Assay for Urinary Metabolites of Benzo[a]pyrene (B[a]P). Polycycl Aromat Compd 1995. [DOI: 10.1080/10406639408015179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
11
|
Grimmer G, Dettbarn G, Jacob J. Biomonitoring of polycyclic aromatic hydrocarbons in highly exposed coke plant workers by measurement of urinary phenanthrene and pyrene metabolites (phenols and dihydrodiols). Int Arch Occup Environ Health 1993; 65:189-99. [PMID: 8282417 DOI: 10.1007/bf00381155] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A filter combination consisting of an impregnated glass fibre and a control filter was used for the collection of air samples in which gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) were determined. To estimate the loss of lower boiling PAHs, d10-phenanthrene was applied as internal standard. A simple, well-producible method for the determination of 1-, 2-, 3-, 4- and 9-hydroxyphenanthrene, 1,2-, 3,4- and 9,10-dihydroxydihydrophenanthrene, 1-hydroxypyrene and 1,2-dihydroxy-1,2-dihydropyrene is described. By means of personal air samplers the exposure to PAHs of four coke plant employees working at different locations was measured over 4 days. Simultaneously the 24-h urine was collected and stored frozen until analysed. The main excretion product of pyrene is a 1-hydroxypyrene conjugate, whereas phenanthrene is excreted predominantly as dihydrodiol conjugate. As expected, workers on the battery topside were exposed the most and accordingly excreted by far the highest amounts of PAHs. Up to 34.0 micrograms phenanthrol conjugates (total of all isomeric phenols) and 195.5 micrograms dihydrodiol conjugates (total of all isomeric dihydrodiols) were excreted in the 24-h urine (mean of 4 days). The metabolite profiles of five isomeric phenanthrene phenols and three isomeric dihydrodiols exhibited only small percentage variations within one individual whereas significant interindividual differences were observed. These findings may indicate a genetically determined enzyme pattern responsible for the metabolic conversion of PAHs.
Collapse
Affiliation(s)
- G Grimmer
- Biochemisches Institut für Umweltcarcinogene, Grosshansdorf, Germany
| | | | | |
Collapse
|
12
|
Abstract
Toxicants can be converted in vivo by a variety of biotransformation reactions into substances that are more, equally, or less noxious than the parent compound. Although conjugation with glutathione is a process that usually results in less harmful products, these products might subsequently form new metabolites that exert more toxicity than the parent compound. These conjugation reactions are catalyzed by several classes of glutathione-S-transferase isoenzymes and thus result in the urinary or biliary excretion of N-acetyl-L-cysteine-S-conjugates (mercapturic acids). Inasmuch as GSH-S-transferase activity varies among different tissues, urinary excretion of mercapturic acids might reflect tissue-specific toxicity. Urinary mercapturic acids are biomarkers of internal and, in some cases, effective dose. The utility of these markers is, however, limited to times shortly after exposure. Studies on possible human deficiencies in some GSH-S-transferases might help us better understand interindividual variations in susceptibility to different toxicants and thus the differences in the pathway of mercapturic acid excretion pattern.
Collapse
Affiliation(s)
- E Nelson
- Toxicology Laboratory, University Medical Center, Essen, Germany
| |
Collapse
|
13
|
Norpoth K, Stücker W, Krewet E, Müller G. Biomonitoring of benzene exposure by trace analyses of phenylguanine. Int Arch Occup Environ Health 1988; 60:163-8. [PMID: 3384481 DOI: 10.1007/bf00378692] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
From preliminary experiments it was known that radiolabelled benzene and some of its metabolites during its metabolic activation process produce different in vitro DNA-phenyladducts in mitoplasts. As we reported previously at least one of these adducts, N-7-phenylguanine, is excreted in the urine of rats in measurable amounts, probably through an excision-repair mechanism after an inhalation experiment. Now we found, after i.p. application of benzene in the urine of rats, a compound separated by cation-exchange chromatography that behaves like a synthesized N-7-phenylguanine reference substance with respect to its retention index and the UV-absorption. This finding could be confirmed by HPLC-measurements with reversed-phase carrier materials. Silylation and gas chromatographic/mass spectrometric (GC/MS) separation of the fraction, which contains the phenylguanine, revealed that these fractions contain further phenyl adducts. Furthermore we studied the time-dependent excretion of the DNA-base adduct. Surprisingly the excretion dropped to zero on the fourth day and showed a new increase thereafter.
Collapse
Affiliation(s)
- K Norpoth
- Institute of Hygiene and Occupational Medicine, University of Essen, Federal Republic of Germany
| | | | | | | |
Collapse
|
14
|
Goksøyr A, Solbakken JE, Klungsøyr J. Regioselective metabolism of phenanthrene in Atlantic cod (Gadus morhua): studies on the effects of monooxygenase inducers and role of cytochromes P-450. Chem Biol Interact 1986; 60:247-63. [PMID: 3791491 DOI: 10.1016/0009-2797(86)90056-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The polycyclic aromatic hydrocarbon phenanthrene was converted mainly (greater than 90%) to the 1,2-dihydrodiol when metabolized in vivo by the marine teleost cod. This is also found in other bony fishes, but contrary to what is known from cartilaginous fish, crustaceans and mammals, where the K-region 9,10-dihydrodiol is the main metabolite. When liver microsomal preparations from differently pretreated cod were incubated with phenanthrene in vitro, the metabolic profile was dramatically different from the in vivo pattern, as shown by gas chromatography-mass spectrometry. The microsomes from untreated, phenanthrene, phenobarbital and pregnenolone-16 alpha-carbonitrile-treated cod converted phenanthrene mainly, but to a varying extent, to the 9,10-dihydrodiol. Treatment with beta-naphthoflavone (BNF), however, resulted in a large increase in the oxidation at the 1,2-position, along with a four- to seven-fold increase in specific activity. The major cytochrome P-450 isozyme purified from BNF-treated cod liver (P-450c) showed highest activity with phenanthrene (a turnover of 0.18 nmol/min per nmol P-450), but with about equal selectivity for the 1,2- and 9,10-region of the substrate in a reconstituted system with phospholipid and NADPH-cytochrome P-450 reductase. The low regioselectivity was also observed as a lack of regioselective inhibition of microsomal phenanthrene metabolism with antiserum to cod P-450c. Two of the minor isozymes, cod cytochromes P-450b and d, showed a similar turnover to P-450c, but with a stronger selectivity for the 1,2-position (55-60%). The results indicate that other control systems, in addition to the content of individual P-450-forms in the regulatory systems, in addition to the content of individual P-450-forms in the endoplasmic reticulum, are involved in the in vivo transformation of phenanthrene by cod to the 1,2-dihydrodiol metabolite.
Collapse
|
15
|
|
16
|
Jacob J, Schmoldt A, Grimmer G. Influence of monooxygenase inducers on the metabolic profile of phenanthrene in rat liver microsomes. Toxicology 1982; 25:333-43. [PMID: 7157409 DOI: 10.1016/0300-483x(82)90111-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The oxidation of phenanthrene by rat liver microsomes significantly depends on the pretreatment of the animals as shown by means of gas chromatography/mass spectrometry. Whereas untreated animals convert phenanthrene exclusively into the 9,10-dihydrodiol (K-region), pretreatment with various polycyclic aromatic hydrocarbons and related compounds resulted in different rates of additional oxidation at the 1,2- and 3,4-position. Moreover, secondary metabolism to dihydrodiol epoxides, detected as triols, was observed. Despite considerable concentration of the proximate carcinogen of phenanthrene (1,2-dihydrodiol) only low concentrations of the ultimate carcinogen were detected which may explain the carcinogenic inefficiency of this hydrocarbon.
Collapse
|
17
|
Abstract
After oral administration of 400 mg curcumin to rats, about 60% of the dose was absorbed. No curcumin was detectable in urine. The urinary excretion of conjugated glucuronides and sulfates significantly increased. No curcumin was present in heart blood. Only traces (less than 5 microgram/ml) in portal blood and negligible quantities in liver and kidney (< 20 micrograms/tissue) were observed from 15 min upto 24 h after administration of curcumin. At the end of 24 h the concentration of curcumin remaining in the lower part of the gut namely caecum and large intestine amounted to 38% of the quantity administered.
Collapse
|
18
|
|
19
|
|
20
|
Chasseaud LF. The nature and distribution of enzymes catalyzing the conjugation of glutathione with foreign compounds. Drug Metab Rev 1974; 2:185-220. [PMID: 4369329 DOI: 10.3109/03602537409030009] [Citation(s) in RCA: 139] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
21
|
Daly JW, Jerina DM, Witkop B. Arene oxides and the NIH shift: the metabolism, toxicity and carcinogenicity of aromatic compounds. EXPERIENTIA 1972; 28:1129-49. [PMID: 4117670 DOI: 10.1007/bf01946135] [Citation(s) in RCA: 516] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
22
|
Sims P. Epoxy derivatives of aromatic polycyclic hydrocarbons. The preparation of benz( )anthracene 8,9-oxide and 10,11-dihydrobenz( )anthracene 8,9-oxide and their metabolism by rat liver preparations. Biochem J 1971; 125:159-68. [PMID: 5158901 PMCID: PMC1178036 DOI: 10.1042/bj1250159] [Citation(s) in RCA: 41] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The syntheses of 10,11-dihydrobenz[a]anthracene 8,9-oxide, benz[a]anthracene 8,9-oxide and 9-hydroxybenz[a]anthracene are described, together with those of a number of related compounds. The epoxides react both chemically and enzymically with water to yield the corresponding dihydrodiols and with reduced glutathione to form glutathione conjugates, and they react chemically with N-acetylcysteine to yield the corresponding mercapturic acids. 8,9-Dihydro-8,9-dihydroxybenz[a]anthracene, formed enzymically from benz[a]anthracene 8,9-oxide, was identical with a dihydrodiol formed when benz[a]anthracene was metabolized by rat liver homogenates. Similarly 10,11-dihydrobenz[a]anthracene 8,9-oxide yielded a dihydrodiol identical with the product formed when 10,11-dihydrobenz[a]anthracene was metabolized.
Collapse
|
23
|
|
24
|
|
25
|
|
26
|
Sims P. Qualitative and quantitative studies on the metabolism of a series of aromatic hydrocarbons by rat-liver preparations. Biochem Pharmacol 1970; 19:795-818. [PMID: 5507686 DOI: 10.1016/0006-2952(70)90243-1] [Citation(s) in RCA: 212] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
27
|
Gillham B, Young L. Biochemical studies of toxic agents. The isolation of premercapturic acids from the urine of animals dosed with chlorobenzene and bromobenzene. Biochem J 1968; 109:143-7. [PMID: 5669843 PMCID: PMC1186763 DOI: 10.1042/bj1090143] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
1. A premercapturic acid, i.e. a compound that yields a mercapturic acid when decomposed by acid, was isolated as a dicyclohexylammonium salt from the urine of rats and rabbits that had been dosed with bromobenzene. 2. Another premercapturic acid was isolated as its dicyclohexylammonium salt from the urine of rats that had been dosed with chlorobenzene. 3. When decomposed by acid, the premercapturic acid from the urine of animals dosed with bromobenzene gave p-bromophenylmercapturic acid, m-and p-bromophenol and NN'-diacetylcystine. 4. The premercapturic acid derived from chlorobenzene gave the corresponding chloro compounds together with NN'-diacetylcystine when decomposed by acid. 5. On the basis of these and other observations it is suggested that the premercapturic acid formed in the metabolism of bromobenzene is N-acetyl-S-(4-bromo-1,2-dihydro-2-hydroxyphenyl)-l-cysteine. 6. It is also suggested that the premercapturic acid derived from chlorobenzene has an analogous structure.
Collapse
|
28
|
Smith RL. The biliary excretion and enterohepatic circulation of drugs and other organic compounds. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRESS IN DRUG RESEARCH. PROGRES DES RECHERCHES PHARMACEUTIQUES 1966; 9:299-360. [PMID: 5326644 DOI: 10.1007/978-3-0348-4021-7_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
29
|
Sims P. Metabolism of polycyclic compounds. 25. The metabolism of anthracene and some related compounds in rats. Biochem J 1964; 92:621-31. [PMID: 5837444 PMCID: PMC1206112 DOI: 10.1042/bj0920621] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
30
|
Boyland E, Kumura M, Sims P. Metabolism of polycyclic compounds. 26. The hydroxylation of some aromatic hydrocarbons by the ascorbic acid model hydroxylating system and by rat-liver microsomes. Biochem J 1964; 92:631-8. [PMID: 5891198 PMCID: PMC1206113 DOI: 10.1042/bj0920631] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
31
|
Boyland E, Sims P. Metabolism of polycyclic compounds. 24. The metabolism of benz[alpha]anthracene. Biochem J 1964; 91:493-506. [PMID: 5840709 PMCID: PMC1202983 DOI: 10.1042/bj0910493] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
32
|
Boyland E, Sims P. Metabolism of polycyclic compounds. 23. The metabolism of pyrene in rats and rabbits. Biochem J 1964; 90:391-8. [PMID: 5836889 PMCID: PMC1202629 DOI: 10.1042/bj0900391] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
33
|
BOYLAND E. The mechanism of tumour induction by aromatic amines and other carcinogens. J Cancer Res Clin Oncol 1963; 65:378-84. [PMID: 14014732 DOI: 10.1007/bf00525366] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|