Benzo pyrene metabolic profile

Wong AKL, Cavalieri E, Rogan E (1986) Dependence of benzo(a]pyrene metabolic profile on the concentration of cumene hydroperoxide with uninduced and induced rat liver microsomes. Biochem Pharmacol 35 1583-1588... 

In this report we compare several properties of hepatic microsomal AHH activity in control and DBA-treated little skates (including metabolic profiles obtained from c-benzo(a)pyrene as elucidated by high pressure liquid chromatography [HPLC]), we describe the partial purification of two different forms of cytochrome P-450 (cytochrome P-448 and cytochrome P-451) from hepatic microsomes of DBA-pretreated little skates and we report polycyclic hydrocarbon-like induction in large numbers of winter flounder assayed in Maine during June, July, and August, which was quite different than data obtained with sheepshead examined in Florida during the same period. 

Nutritional and nutritional status markedly influence xenobiotic metabolism in laboratory animals. Microsomes were prepared from the livers of rats which had been fed chow or modified AIN-76 diets with or without oxidized or unoxidized sulfur amino acids for 7 days. The pattern of benzo(a)pyrene (BaP) metabolites formed by each microsomal preparation in the presence of a NADPH-generating system was determined using high performance liquid chromatography (HPLC). The results indicate that oxidized sulfur amino acids induce different forms of cytochromes P-450 in rat liver Which are reflected by different BaP metabolic profiles. 

A Ramesh, F Inyang, DB Hood, A Archibong, AM Nyanda, ME Knucles. Oral bio availability and metabolic profile of benzo(a)pyrene [B(a)p] in F-344 rats. Proceedings of the International Society for the Study of Xenobiotics, Nashville, 1999, p. 236. 

Jacob J, Schmoldt A, Grimmer G. 1983a. Benzo[e]pyrene metabolism in rat liver microsomes Dependence of the metabolite profile on the pretreatment of rats with various monooxygenase inducers. Carcinogenesis 4(7) 905-910. 

Wood AW, Levin W, Thakker DR, et al. 1979b. Biological activity of benzo[e]pyrene An assessment based on mutagenic activities and metabolic profiles of the polycyclic hydrocarbon and its derivatives. J Biol Chem 254(11) 4408-4415. 

Generally, the PAH components of wood creosote, coal tar creosote, coal tar, and coal tar pitch are metabolized by oxidative enzymes in the liver and lungs to generate active metabolites that can bind to macromolecules. The metabolic profiles vary among species and compounds, but the components follow the same major reaction pathways. Hence, the metabolites are structurally very similar. The proposed metabolic scheme for a representative PAH, benzo[a]pyrene, is presented in Figure 3-4. The principal... 

Comparison of the metabolic profiles of benzo(a)pyrene obtained from primary cell cultures and subcellular fractions derived from normal and methylcholanthrene-induced rat liver. Cancer Letters 5 81-89. 

J. McCann and B. N. Ames, Detection of carcinogens as mutagens in the Salmonella/ microsome test Assay of 300 chemicals, Proc. Natl. Acad. Sci. U.S.A. 72, 5135-5139 (1975). I. Schmeltz, J. Tosk, and G. M. Williams, Comparison of the metabolic profiles of benzo(a)pyrene obtained from primary cell cultures and subcellular fractions derived from normal and methylcholanthrene-induced rat liver. Cancer Lett. 5, 81-89, (1978). 

Each plant tissue tends to have an obviously distinctive profile of flavonoids. The flavonoid content can reach about 0.5% in pollen, 10% in propolis, and about 6 mg/kg in honey. Havonoid aglycones appear to be present only in propolis and honey, while pollen contains flavanols in herosidic forms. The flavonoids in honey and propolis have been identified as flavanones and flavanones/flavanols (Campos et ah, 1990). The antimi-crobially active flavanone pinocembrine was foimd to be a major flavonoid in honey (Bogdanov, 1989). Amiot et ah (1989) studied two blossom and two honeydew Swiss honey samples and foimd that pinocembrine was the main flavonoid. Pinocembrine concentration varied between 2 and 3 mg/kg (Bogdanov, 1989). Berahia et ah (1993) analyzed sunflower honey samples and detected six flavone/flavols, four flavanone/ flavols, and pinocembrin, of which pinocembrin is the main flavonoid. The flavonoids in sunflower honey and propolis were characterized and assessed for their effects on hepatic drug-metabolizing enzymes and benzo [fl]pyrene-DNA adduct formation (Sabatier et ah, 1992 Siess et ah, 1996). 

Several xenobiotics can induce enzymes to influence the rat liver microsomal metabolite profiles of various PAHs. For example, AHH, the cytochrome P-450 isoenzyme believed to be primarily responsible for the metabolism of benzo[a]pyrene and other PAHs, is subject to induction by PAHs. 

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