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Merugu NK, Manapuram S, Chakraborty T, Karanam SK, Imandi SB. Mutagens in commercial food processing and its microbial transformation. Food Sci Biotechnol 2023; 32:599-620. [PMID: 37009045 PMCID: PMC10050501 DOI: 10.1007/s10068-022-01240-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/21/2022] [Accepted: 12/27/2022] [Indexed: 02/01/2023] Open
Abstract
Mutagens are chemical molecules that have the ability to damage DNA. Mutagens can enter into our body upon consumption of improperly cooked or processed food products such as high temperature or prolonged cooking duration. Mutagens are found in the food products can be classified into N-nitroso derivatives, polycyclic aromatic hydrocarbons, and heterocyclic aromatic amines. Food products with high fat and protein content are more prone to mutagenic formation. Microorganisms were found to be a potent weapon in the fight against various mutagens through biotransformation. Therefore, searching for the microorganisms which have the ability to transform mutagens and the development of techniques for the identification as well as detection of mutagens in food products is much needed. In the future, methods for the identification and detection of these mutagens as well as the identification of new and more potent microorganisms which can transform mutagens into non-mutagens are much needed.
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Affiliation(s)
- Narendra Kishore Merugu
- Department of Biotechnology, GITAM School of Technology, Gandhi Institute of Technology and Management (GITAM) Deemed to be University, Gandhi Nagar, Rushikonda, Visakhapatnam, Andhra Pradesh 530 045 India
| | - Saikumar Manapuram
- Department of Biotechnology, GITAM School of Science, Gandhi Institute of Technology and Management (GITAM) Deemed to be University, Gandhi Nagar, Rushikonda, Visakhapatnam, Andhra Pradesh 530 045 India
- Department of Genetic Toxicology, Vipragen Biosciences Private Limited, No. 67B, Hootagalli Industrial Area, Mysuru, Karnataka 570 018 India
| | - Tanushree Chakraborty
- Department of Biotechnology, GITAM School of Technology, Gandhi Institute of Technology and Management (GITAM) Deemed to be University, Gandhi Nagar, Rushikonda, Visakhapatnam, Andhra Pradesh 530 045 India
- Department of Biotechnology, GITAM School of Science, Gandhi Institute of Technology and Management (GITAM) Deemed to be University, Gandhi Nagar, Rushikonda, Visakhapatnam, Andhra Pradesh 530 045 India
| | - Sita Kumari Karanam
- Maharajah’s College of Pharmacy, Phool Baugh, Vizianagaram, Andhra Pradesh 535 002 India
| | - Sarat Babu Imandi
- Department of Biotechnology, GITAM School of Technology, Gandhi Institute of Technology and Management (GITAM) Deemed to be University, Gandhi Nagar, Rushikonda, Visakhapatnam, Andhra Pradesh 530 045 India
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De Buck SS, Augustijns P, Muller CP. Specific antibody modulates absorptive transport and metabolic activation of benzo[a]pyrene across Caco-2 monolayers. J Pharmacol Exp Ther 2005; 313:640-6. [PMID: 15665140 DOI: 10.1124/jpet.104.081034] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It has been shown that oral anticarcinogen antibodies can decrease intestinal absorption of procarcinogens. So far, no attempts have been made to understand the potential modulatory effect of such antibodies on metabolic activation at mucosal surfaces. Moreover, the influence of naturally induced serosal-specific antibodies on absorptive transport of carcinogens remains unknown. In this study, the prototype food carcinogen benzo[a]pyrene (B[a]P) and a specific monoclonal antibody were used to address these questions in a bicompartmental model of polarized intestinal cells (Caco-2). Apical (i.e., luminal) administration of a 30-fold molar excess antibodies increased about 25-fold recovery of unmetabolized B[a]P, concomitantly with a decrease of 80% in both absorptive transport and formation of phenol metabolites. Interestingly, when metabolism was slowed down by antibodies, cross-reactive antibodies also increased at least 5-fold the extracellular levels of the 7,8-diol-B[a]P, interrupting subsequent activation steps. On the other hand, basolateral antibodies changed by 8-fold the rate of carcinogen appearance in the basolateral compartment, albeit without interfering with the apical cellular uptake or sequestration of either B[a]P or 7,8-diol-B[a]P by apical antibodies. Furthermore, basolateral antibodies reduced exposure of Caco-2 monolayers to B[a]P as demonstrated by a 50% decrease in apical efflux of 3-OH-B[a]P. These data show for the first time that both luminal and serosal antibodies may reduce the carcinogenic process by preventing high local concentrations, which would overload DNA repair mechanisms. This study also sheds light on the relevance of both naturally induced and immunoprophylactic antibodies against polycyclic aromatic hydrocarbon carcinogens.
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Affiliation(s)
- Stefan S De Buck
- Institute of Immunology, National Health Institute of Luxembourg
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Siddhuraju P, Makkar H, Becker K. The effect of ionising radiation on antinutritional factors and the nutritional value of plant materials with reference to human and animal food. Food Chem 2002. [DOI: 10.1016/s0308-8146(01)00398-3] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pereira RA, Koifman S. Associação entre fatores da dieta e tumores de cérebro em adultos: uma revisão da literatura. CAD SAUDE PUBLICA 2001. [DOI: 10.1590/s0102-311x2001000600003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Desenvolveu-se uma revisão da literatura científica publicada entre 1986 e 1999, sobre a associação entre fatores da dieta e os tumores de cérebro em adultos, com o objetivo de descrever as associações observadas e discutir os aspectos metodológicos que possam influenciar os resultados observados. De um modo geral, os estudos revisados parecem apontar na direção de uma associação moderada entre os fatores da dieta e os tumores de cérebro; há evidências de que o consumo de compostos N-nitroso possa favorecer o desenvolvimento desses tumores, e de que o consumo de vegetais e frutas pode ter papel na sua inibição. A participação dos respondentes substitutos nos estudos analisados, pode ter introduzido viés de memória nas informações levantadas e contribuído para a inconsistência dos achados. As investigações epidemiológicas sobre a associação da dieta com estes tumores devem considerar a análise de outros fatores alimentares, além dos compostos N-nitroso. É necessário precisar os períodos de exposição que devem ser investigados e contar com criteriosa metodologia, de modo a prevenir a ocorrência de tendenciosidades relacionadas com a seleção dos controles e minimizar os efeitos do viés de memória.
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Luceri C, De Filippo C, Caderni G, Gambacciani L, Salvadori M, Giannini A, Dolara P. Detection of somatic DNA alterations in azoxymethane-induced F344 rat colon tumors by random amplified polymorphic DNA analysis. Carcinogenesis 2000; 21:1753-6. [PMID: 10964108 DOI: 10.1093/carcin/21.9.1753] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Colon carcinogenesis induced in rats by azoxymethane (AOM) is a useful experimental model as it mimics the human adenoma-carcinoma sequence and allows the study of dietary variation and of the effects of chemopreventive substances. Alterations of specific oncogenes and tumor suppressor genes (APC and K-ras) play roles at different stages of this carcinogenesis process. Recently, it has been suggested that genomic instability is the necessary step for the generation of multiple mutations underlying the occurrence of cancer. We studied the frequency of K-ras and microsatellite instability (MSI) in 30 colorectal tumors induced by AOM (30 mg/kg) in F344 rats. We also used the random amplified polymorphic DNA (RAPD) method to identify genomic alterations in chemically induced aberrant crypt foci (ACF), adenomas and adenocarcinomas. K-ras mutations were identified in 16.7% of the cases (5/30; 9% in adenomas and 37.5% in adenocarcinomas) and MSI in 20% (6/30) of the tumors (only one sample exhibited instability at more than one locus). Of 21 primers used for the RAPD assay, six were very informative. All the analyzed tumors (16/16) showed at least one RAPD profile with lost or additional bands compared with the normal mucosa. A lower level of genomic alteration was present in the ACF analyzed (7/10). In conclusion, K-ras and MSI are not often involved in the AOM carcinogenesis in the rat, whereas extensive genomic instability is always present and can be detected using the RAPD analysis.
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Affiliation(s)
- C Luceri
- Department of Pharmacology, University of Florence, Viale Pieraccini 6, 50139 Florence and USL, 10/H Antella, Florence, Italy
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Abstract
Several markers of colon cancer have been described in humans. The study of polyp recurrence is a reliable procedure, but long and expensive. Mucosal cell proliferation is increased in high-risk subjects, often with a displacement of proliferation toward the lumen. Increased apoptosis in colon crypts is associated with protection against experimental cancer, but the method is not validated for humans. Aberrant crypt foci (ACF) can be scored in humans in resected specimens or visualized endoscopically. ACF and colon cancer risk seem connected in Japan, but not in Europe or North America. In conclusion, assessment of individuals or populations at risk of colon cancer still relies on a combination of different methods.
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Affiliation(s)
- P Dolara
- Department of Pharmacology, University of Florence, Viale Pieraccini 6, 50139, Florence, Italy.
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Singh A, Rao AR. Modulatory influence of arecanut on the mouse hepatic xenobiotic detoxication system and skin papillomagenesis. TERATOGENESIS, CARCINOGENESIS, AND MUTAGENESIS 1995; 15:135-46. [PMID: 8584985 DOI: 10.1002/tcm.1770150306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The modulatory influence of arecanut, a masticatory in several human populations, on the levels of biotransformation system enzymes in mouse liver has been studied. Swiss albino mice of either sex (4 weeks old) were fed on diets containing 0.25%, 0.5%, or 1% arecanut (w/w) for 5 weeks. In addition, a group of mice received a 1% arecanut diet for 36 weeks. The findings revealed a significant increase in hepatic levels of cytochrome b5, cytochrome P-450, malondialdehyde (MDA), and glutathione S-transferase (GST). The hepatic -SH content was depressed by 0.5% and 1% arecanut diets. Long-term feeding of a 1% arecanut diet elicited changes similar to those seen following treatment for 5 weeks. Arecanut-modulated profiles of biotransformation enzymes and antioxidant levels are suggestive of its influence in the process of carcinogenesis induced by bioactivated electrophilic species of potential chemical carcinogens among habitual arecanut chewers. Arecanut was also tested for its potency either to induce or to alter 7,12-dimethylbenz[a]anthracene (DMBA)-induced papillomagenesis in the skin of the mouse. Animals put on a 1% arecanut diet and treated with a standard two-stage protocol for tumor induction developed a 5.41 tumor burden (control value: 5.76) along with 100% incidence of mice bearing papillomas (control value: 94.4%), thus signifying that dietary intake of 1% arecanut for 18 weeks could not induce/alter the mouse skin tumorigenesis pattern.
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Affiliation(s)
- A Singh
- Cancer Biology Laboratory, School of Life Sciences, Jawaharlal Nehur University, New Delhi, India
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Abstract
Salted, sun-dried and deep-fried fish and mutton were screened for their mutagenicity by the Ames test, single cell gel electrophoresis assay (SCG), chromosomal aberrations (CA), and micronucleus test. Fish and mutton given at 20% in the diet to the rats daily for 2 months resulted in cytogenetic damage which could not be repaired on withdrawal. However, the temporary damage was reversed at a 10% dose upon withdrawal after the same period. The maximum chromatid damage, found as breaks and gaps, was in agreement with the increased number of strand breaks. Treated rats also showed DNA strand breaks in hepatocytes and lymphocytes, more so in hepatocytes. Lime and onion extracts inhibited the nitrosation of fish and mutton, and were antitoxic.
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Affiliation(s)
- S Taj
- Department of Microbiology and Tumor Biochemistry, Cancer Institute, Adyar, Madras, India
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Ceci A, de Terlizzi M, Colella R, Loiacono G, Balducci D, Surico G, Castello M, Testi AM, De Bernardi B, Indolfi P. Langerhans cell histiocytosis in childhood: results from the Italian Cooperative AIEOP-CNR-H.X '83 study. MEDICAL AND PEDIATRIC ONCOLOGY 1993; 21:259-64. [PMID: 8469220 DOI: 10.1002/mpo.2950210405] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Ninety patients with biopsy-proven Langerhans cell histiocytosis (LCH) were enrolled from June, 1983, to December, 1988, in the multicenter AIEOP-CNR-H.X. '83 study. They were divided into two groups: poor prognosis (PP), comprising 11 children with organ dysfunction (OD), and good prognosis (GP), made up of 79 patients without OD. Eighty-four patients were evaluable for treatment results. Among GP patients, 16 with a single lesion received only local treatment, while 59 entered a clinical trial of immunotherapy and/or monochemotherapy with vinblastine (VBL). Nonresponders, sequentially received doxorubicin (ADM) and then etoposide (VP16). PP patients were treated with 4 week cycles of vincristine, ADM, cyclophosphamide, and prednisone for nine courses. The overall survival was 92.8% (100% for GP patients and 45.5% for PP patients) at 48 months. The complete response (CR) rates for immunotherapy, VBL, ADM, and VP16 were 10%, 62.9%, 42.8%, and 88.2%, respectively. Two of the 11 PP patients had a CR (18.2%), while six died and three are still alive with recurrent disease. The overall incidence of disease-related disabilities was 47.7%, while that of diabetes insipidus was 20%. Monochemotherapy is probably adequate in GP patients, while more effective treatments are needed for PP patients.
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Affiliation(s)
- A Ceci
- Second Department of Pediatrics, University of Bari, Italy
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Abstract
Extensive epidemiological and experimental studies have suggested that some chemical agents, nutritional deficiencies, and physical factors are associated with the development of esophageal cancer (EC). Recent evidence also suggests an etiologic role of certain microorganisms in esophageal carcinogenesis either by producing carcinogens or promotors or by acting directly on the host cells. The mutagenic and carcinogenic effects of several fungi and bacteria isolated from the grains and foodstuffs in high-risk areas have been shown by in vitro and in vivo studies. Certain viruses, e.g., human papillomavirus, herpes simplex virus, cytomegalovirus, and Epstein-Barr virus, have been implicated in the pathogenesis of a variety of human cancers, and all of them are known to produce tumors in animals and cell transformation in vitro. These viruses also have been shown to infect the esophageal epithelium. Therefore, although many of the key issues of their mechanisms of action are unclear as yet, they should be considered potential etiologic agents of EC. The present review summarizes the data available on the etiology of EC, emphasizing the current evidence implicating an etiologic role of microorganisms in the pathogenesis of this malignancy.
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Affiliation(s)
- F Chang
- Department of Pathology, University of Kuopio, Finland
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Hasegawa R, Shirai T, Hakoi K, Takaba K, Iwasaki S, Hoshiya T, Ito N, Nagao M, Sugimura T. Synergistic enhancement of glutathione S-transferase placental form-positive hepatic foci development in diethylnitrosamine-treated rats by combined administration of five heterocyclic amines at low doses. Jpn J Cancer Res 1991; 82:1378-84. [PMID: 1778761 PMCID: PMC5918350 DOI: 10.1111/j.1349-7006.1991.tb01809.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Potential synergism among 5 heterocyclic amines at low doses in the induction of glutathione S-transferase placental form (GST-P)-positive liver cell foci was examined in an 8-week experiment using male rats initially given diethylnitrosamine (200 mg/kg, ip). The heterocyclic amines applied were 3-amino-1-methyl-5H-pyrido[4,3-b]indole (500 ppm), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]-imidazole (500 ppm), 2-amino-3-methyl-9H-pyrido[2,3-b]indole (800 ppm), 2-amino-9H-pyrido[2,3-b]indole (800 ppm), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP, 400 ppm). Separate groups received each chemical at the dose used in earlier carcinogenicity assays (above doses), at 1/5 or 1/25 of these, or all 5 chemicals together, each at the 1/5 or 1/25 levels. The numbers and areas of GST-P-positive foci were significantly increased with all chemicals, except for PhIP, at the highest dose, the results being consistent with the reported liver carcinogenicity. In the combined treatment at the 1/5 dose levels, synergistic enhancement occurred; the numbers and areas of foci were significantly increased above the sums of individual data. However, this was not the case for the 1/25 dose groups. Although the synergism between pyrolysis products in liver carcinogenesis depended on the dose and combination of chemicals, the findings, together with those from a previous experiment using 5 different heterocyclic amines, are of particular significance since several heterocyclic amines might be simultaneously generated during cooking of foodstuffs.
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Affiliation(s)
- R Hasegawa
- First Department of Pathology, Nagoya City University Medical School
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Abstract
It now appears likely that the development of colonic adenomas and carcinomas involves a series of steps in which environmental or endogenous carcinogens induce or promote neoplasia through the accumulation of multiple, specific genetic mutations. Genetic predisposition to this process may take the form of inherited defects in control of cellular proliferation as in familial polyposis coli, or genetically determined polymorphism which affects enzyme activities relevant to the production or detoxication of carcinogens. Genetic effects may also influence levels of hormones and/or their target cell receptors which regulate the metabolic and proliferative activity of colonocytes. This review highlights data suggesting a role for polymorphism associated with xenobiotic acetylation, hydroxylation, and conjugation with glutathione in the metabolism of potential carcinogens, as well as for dehydroepiandrosterone in the metabolic control of cell proliferation. The study of genetically determined polymorphism in colorectal cancer may provide new insights into the epidemiology of cancer and result in new methods for the detection of higher risk groups.
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Affiliation(s)
- M J Fettman
- Department of Gastroenterology, Queen Elizabeth Hospital, Woodville South, South Australia
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Abstract
Curative surgery is possible in only a small minority of patients with pancreatic cancer and, to date, responses to chemotherapy and radiotherapy have been disappointing. To make any impact on the incidence of the disease a clearer understanding of its aetiology is required. This review explores present knowledge of the aetiology and epidemiology of pancreatic cancer.
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Affiliation(s)
- G Haddock
- University Department of Surgery, Royal Infirmary, Edinburgh, UK
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Howes AJ, Chan VS, Caldwell J. Structure-specificity of the genotoxicity of some naturally occurring alkenylbenzenes determined by the unscheduled DNA synthesis assay in rat hepatocytes. Food Chem Toxicol 1990; 28:537-42. [PMID: 2242826 DOI: 10.1016/0278-6915(90)90152-d] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A number of alkenylbenzenes related to safrole and estragole are known to be hepatocarcinogenic in rats and/or mice, apparently by a genotoxic mechanism. However, they are not bacterial mutagens in the Ames test. We have studied the ability of a series of carcinogenic and non-carcinogenic congeners to induce unscheduled DNA synthesis (UDS) in freshly isolated rat hepatocytes in primary culture. The cytotoxicity of these compounds was assessed by lactate dehydrogenase leakage. There was an excellent correlation between UDS induction and known rodent hepatocarcinogenicity, with safrole, estragole and methyleugenol all inducing UDS. Anethole, isosafrole, eugenol and allylbenzene, for which evidence of carcinogenicity is equivocal or negative, did not induce UDS. All compounds were markedly cytotoxic at concentrations between 10(-3) and 10(-2) M, irrespective of their structural features. The data are discussed with reference to the known structure dependence of the disposition of the alkenylbenzenes, notably their metabolic activation, with which there are excellent correlations. The demonstration of the genotoxicity of rodent hepatocarcinogenic alkenylbenzenes in cells cultured from the in vivo target organ will allow the direct investigation of factors influencing these processes and facilitate the safety evaluation of these important natural flavours.
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Affiliation(s)
- A J Howes
- Department of Pharmacology and Toxicology, St Mary's Hospital Medical School, London, UK
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Tucker JD, Carrano AV, Allen NA, Christensen ML, Knize MG, Strout CL, Felton JS. In vivo cytogenetic effects of cooked food mutagens. Mutat Res 1989; 224:105-13. [PMID: 2770773 DOI: 10.1016/0165-1218(89)90009-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Using a variety of in vivo cytogenetic endpoints, we have investigated the effects of several compounds formed during the cooking of meat. C57Bl/6 mice were used to test for an increase in the frequency of sister-chromatid exchanges (SCEs), chromosomal aberrations, and micronucleated erythrocytes by 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx). 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). MeIQx and DiMeIQx did not induce SCEs in mouse bone marrow cells. PhIP induced sister-chromatid exchanges, but not chromosomal aberrations in bone marrow. In peripheral blood lymphocytes, PhIP did induce aberrations at 100 mg/kg, the highest dose tested. PhIP induced a low but significantly increased frequency of micronuclei in normochromatic but not polychromatic erythrocytes in bone marrow and peripheral blood. However, dose responses were not observed. With the exception of the SCEs induced by PhIP, these results contrast with observations made in vitro, where these compounds were found to have significant genotoxicity in mammalian cells and a very high mutation frequency in prokaryotic systems.
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Affiliation(s)
- J D Tucker
- Biomedical Sciences Division, Lawrence Livermore National Laboratory, CA 94550
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Ayrton AD, Ioannides C, Walker R. Induction of rat hepatic cytochrome P-450 I proteins by the antimutagen anthraflavic acid. Food Chem Toxicol 1988; 26:909-15. [PMID: 3209131 DOI: 10.1016/0278-6915(88)90088-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Administration of the antimutagen anthraflavic acid to rats gave rise to significant increases in the hepatic microsomal O-deethylations of ethoxyresorufin and ethoxycoumarin, but not in the O-dealkylation of pentoxyresorufin nor in cytosolic glutathione S-transferase activity. Immunoblot studies of solubilized microsomes from anthraflavic acid-treated rats revealed that anthraflavic acid induced the apoproteins P-450 I A1 and A2 but not P-450 B1 and B2. Pretreatment with anthraflavic acid resulted in a marked increase in the in vitro bioactivation of 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole and 2-amino-3,2-amino-3-methylimidazomethylimidazo[4,5-f]-quinoline (IQ) to mutagenic intermediate(s); IQ is a carcinogen against which anthraflavic acid has displayed strong antimutagenic effect in the Ames test when incorporated into the metabolic activation system. The increase in mutagenicity of IQ was the result of enhancement of both the microsomal and cytosolic activation steps. It is concluded that anthraflavic acid is a specific inducer of P-450 I proteins in the rat and this compound is not only unlikely to exhibit any anticarcinogenic effect in vivo but may act as a co-carcinogen.
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Affiliation(s)
- A D Ayrton
- Department of Biochemistry, University of Surrey, Guildford, England
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