CYTOCHROME-P450 2A OF NASAL EPITHELIUM - REGULATION AND ROLE IN CARCINOGEN METABOLISM

被引:47
作者
BEREZIAT, JC
RAFFALLI, F
SCHMEZER, P
FREI, E
GENESTE, O
LANG, MA
机构
[1] INT AGCY RES CANC,MECHANISMS CARCINOGENESIS UNIT,F-69372 LYON 08,FRANCE
[2] DEUTSCH KREBSFORSCHUNGSZENTRUM,DIV TOXICOL & ENVIRONM CARCINOGENESIS,W-6900 HEIDELBERG,GERMANY
关键词
NITROSAMINES; AFLATOXIN B-1; METABOLISM; CYP2A-5; REGULATION; NASAL EPITHELIUM; RAT;
D O I
10.1002/mc.2940140209
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
In this study, we found that rat nasal coumarin-7-hydroxylase (COH) activity was two orders of magnitude higher than rat hepatic COH activity and could be induced by adding coumarin to the rats' drinking water. In western blot analysis, an anti-cytochrome P450 (Cyp) 2a-5 (mouse liver COH) antibody recognized a sharp band in the microsomal fraction of rat nasal epithelium but not of the liver; the band comigrated with Cyp2a-5. The intensity of the band was increased by the coumarin treatment. Similarly, in northern blot analysis, a cDNA probe specific for Cyp2a-5 recognized an mRNA in the nasal epithelium having the same size as mouse liver Cyp2a-5 mRNA; however, no hybridizable mRNA was recognized in liver preparations. Unlike the protein level, the level of the mRNA was not increased by coumarin. When northern blot analyses were performed with two oligoprobes specific for rat lung CYP2A3, an mRNA of similar size to Cyp2a-5 mRNA was recognized. In immunoinhibition analysis, anti-Cyp2a-5 antibody inhibited rat nasal COH activity and aflatoxin B-1 (AFB(1)) metabolism completely. It inhibited N-nitrosodiethylamine (NDEA) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) metabolism by 80-90%. In contrast, the hepatic metabolism of the four compounds was not affected by the antibody. When coumarin instead of anti-Cyp2a-5 antibody was used, a strong but variable inhibition of the nasal metabolism of AFB(1), NDEA, and NNK was seen. The results suggest that an enzyme or enzymes similar to mouse liver Cyp2a-5, one of which may be CYP2A3, is expressed at high levels in rat nasal epithelium but not in the liver and that its expression is increased by coumarin, an odorant and a substrate of Cyp2a-5. The increase probably occurs by protein stabilization or stimulation of translation. The results also show that the enzyme has a key role in the nasal metabolism of three well-known carcinogens, AFB(1), NDEA, and NNK and may therefore be an important contributing factor in nasal carcinogenesis. (C) 1995 Wiley-Liss, Inc.
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页码:130 / 139
页数:10
相关论文
共 47 条
[21]   IDENTIFICATION OF A NOVEL P450 EXPRESSED IN RAT LUNG - CDNA CLONING AND SEQUENCE, CHROMOSOME MAPPING, AND INDUCTION BY 3-METHYLCHOLANTHRENE [J].
KIMURA, S ;
KOZAK, CA ;
GONZALEZ, FJ .
BIOCHEMISTRY, 1989, 28 (09) :3798-3803
[22]   CLEAVAGE OF STRUCTURAL PROTEINS DURING ASSEMBLY OF HEAD OF BACTERIOPHAGE-T4 [J].
LAEMMLI, UK .
NATURE, 1970, 227 (5259) :680-+
[23]   MOUSE-LIVER P450COH - GENETIC-REGULATION OF THE PYRAZOLE-INDUCIBLE ENZYME AND COMPARISON WITH OTHER P450-ISOENZYMES [J].
LANG, MA ;
JUVONEN, R ;
JARVINEN, P ;
HONKAKOSKI, P ;
RAUNIO, H .
ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS, 1989, 271 (01) :139-148
[24]   METABOLISM OF AFLATOXIN-B1 IN THE BOVINE OLFACTORY MUCOSA [J].
LARSSON, P ;
PETTERSSON, H ;
TJALVE, H .
CARCINOGENESIS, 1989, 10 (06) :1113-1118
[25]   DISPOSITION OF H-3 AFLATOXIN-B1 IN MICE - FORMATION AND RETENTION OF TISSUE BOUND METABOLITES IN NASAL GLANDS [J].
LARSSON, P ;
HOEDAYA, WI ;
TJALVE, H .
PHARMACOLOGY & TOXICOLOGY, 1990, 67 (02) :162-171
[26]   IDENTIFICATION AND BIOCHEMICAL-ANALYSIS OF NOVEL OLFACTORY-SPECIFIC CYTOCHROME-P-450IIA AND UDP-GLUCURONOSYL TRANSFERASE [J].
LAZARD, D ;
TAL, N ;
RUBINSTEIN, M ;
KHEN, M ;
LANCET, D ;
ZUPKO, K .
BIOCHEMISTRY, 1990, 29 (32) :7433-7440
[27]   BIOTRANSFORMATION ENZYMES IN NASAL-MUCOSA AND LIVER OF SPRAGUE-DAWLEY RATS [J].
LONGO, V ;
CITTI, L ;
GERVASI, PG .
TOXICOLOGY LETTERS, 1988, 44 (03) :289-297
[28]   METABOLISM OF DIETHYLNITROSAMINE BY MICROSOMES OF HUMAN RESPIRATORY NASAL-MUCOSA AND LIVER [J].
LONGO, V ;
PACIFICI, GM ;
PANATTONI, G ;
URSINO, F ;
GERVASI, PG .
BIOCHEMICAL PHARMACOLOGY, 1989, 38 (11) :1867-1869
[29]   METABOLISM OF DIETHYLNITROSAMINE BY NASAL-MUCOSA AND HEPATIC MICROSOMES FROM HAMSTER AND RAT - SPECIES SPECIFICITY OF NASAL-MUCOSA [J].
LONGO, V ;
CITTI, L ;
GERVASI, PG .
CARCINOGENESIS, 1986, 7 (08) :1323-1328
[30]  
LOWRY OH, 1951, J BIOL CHEM, V193, P265