Beta naphthoflavone

Details of some inducible P450 forms that play key roles in the metabolism of xenobiotics are shown in Table 2.4. P450s belonging to family lA are induced by various lipophilic planar compounds including PAHs, coplanar PCBs, TCDD and other dioxins, and beta naphthoflavone (Monod 1997). As noted earlier, such planar compounds are also substrates for P450 lA. In many cases, the compounds induce the enzymes that will catalyze their own metabolism. Exceptions are refractory compounds such as 2,3,7,8-TCDD, which is a powerful inducer for P450 lA but a poor substrate. 

Oikari, A. and B. Jimenez. 1992. Effects of hepatotoxicants on the induction of microsomal monooxygenase activity in sunfish liver by beta-naphthoflavone and benzo[a]pyrene. Ecotoxicol. Environ. Safety 23 89-102. 

Patriarca, C. et al., Popliteal lymph node response to procainamide and isoniazid. Role of beta-naphthoflavone, phenobarbitone and S9-mix pretreatment. Toxicol. Lett., 66, 21, 1993... 

Moochhala. 1 Methyl 4 phenyh 1,2,3, 6 tetrahydropyridine induced neuro-toxicity partial protection against striato-nigral dopamine depletion in C57BL/6J mice by cigarette smoke ex-posure and by beta-naphthoflavone-pretreatment. Neurosci Lett 1991 127(2) 247-250. 

Celander, M. and Forlin, L. (1992). Quantification of cytochrome P450 lAl and catalytic activities in liver microsomes of isosafiol-treated and beta-naphthoflavone-treated rainbow trout Oncorhynchus mykiss). Marine Environmental Research, 34 123-126. 

Melancon, M.J., C.R. Elcombe, M.J. Vodicnik and J.J. Lech. Induction of cytochromes P450 and mixed-function oxidase activity by polychlorinated biphenyls and beta-naphthoflavone in carp (Cyprinus carpio). Comp. Biochem. Physiol. 69C 219-226, 1981. 

Monod, G., M.A. Boudry and C. Gillet. Biotransformation enzymes and their induction by beta-naphthoflavone during embryolarval development in salmonid species. Comp. Biochem. Physiol. 114C 45-50, 1996. 

Schlenk, D., D.M. Stresser, J.C. McCants, A.C. Nimrod and W.H. Benson. Influence of beta-naphthoflavone and methoxychlor pretreatment on the biotransformation and estrogenic activity of methoxychlor in channel catfish (Ictalurus punctatus). Toxicol. Appl. Pharmacol. 145 349-356, 1997. 

Fong, A.T., J.D. Hendricks, R.H. Dashwood, S. Vanwinkle, B.C. Lee and G.S. Bailey. Modulation of diethylnitrosamine-induced hepatocarcinogenesis and O-6-ethylguanine formation in rainbow trout by indole-3-carbinol, beta-naphthoflavone and aroclor-1254. Toxicol. Appl. Pharmacol. 96 93-100, 1988. 

Takahashi, N., C.L. Miranda, M.C. Henderson, D.R. Buhler, D.E. Williams and G.S. Bailey. Inhibition of in vitro aflatoxin B1 DNA binding in rainbow trout by CYP1A inhibitors - alpha-naphthoflavone, beta-naphthoflavone and trout CYP1A1 peptide antibody. Comp. Biochem. Physiol. 110C 273 -280, 1995. 

Weber, L.P. and D.M. Janz. Effects of beta-naphthoflavone and dimethylbenz[a]anthracene on apoptosis and HSP70 expression in juvenile channel catfish (Ictalurus punctatus) ovary. Aquat. Toxicol. 54 39-50, 2001. 

Guengerich, F. P., Dannan, G. A., Wright, S. T, Martin, M. V., and Kaminsky, L. S. (1982). Purification and characterization of liver microsomal cytochromes p-450 Electrophoretic, spectral, catalytic, and immunochemical properties and inducibility of eight isozymes isolated from rats treated with phenobarbital or beta-naphthoflavone. Biochemistry 21, 6019-6030. 

The cytochrome P450 inducers phenobarbital and beta-naphthoflavone slightly inhibited the growth of C. roseus suspension cultures. Phenobarbital increased serpentine accumulation in cells in a production medium, but not in cells grown in a normal B5-growth medium. The cytochrome P450 inhibitor ketoconazole was found to inhibit serpentine production (114). No measurements of GlOH activities were performed. 

Washburn, B. S., Vines, C. A., Baden, D. G. et al.. Differential effects of brevetoxin and [beta]-naphthoflavone on xenobiotic metabolizing enzymes in striped bass (Morone saxatilis), Aquat. Toxicol. 35,1, 1996. 

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