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Journal articles on the topic 'Beta-naphthoflavone'

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Published: 11 March 2023

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1

Bars, R. G., A. M. Mitchell, C. R. Wolf, and C. R. Elcombe. "Induction of cytochrome P-450 in cultured rat hepatocytes. The heterogeneous localization of specific isoenzymes using immunocytochemistry." Biochemical Journal 262, no. 1 (August 15, 1989): 151–58. http://dx.doi.org/10.1042/bj2620151.

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Primary cultures of rat hepatocytes were exposed to phenobarbitone, clofibric acid, beta-naphthoflavone, isosafrole or dexamethasone for 3 days, and the induction of several cytochrome P-450 isoenzymes was demonstrated by increased catalytic activity, by Western blotting and by immunocytochemistry. The profiles of isoenzymes induced in vitro were compared with those induced in liver microsomes of rats dosed with the same agents. Clofibric acid, an agent which has not been thoroughly investigated previously, was shown to induce both in vivo and in vitro several P-450 isoenzymes normally inducible by phenobarbitone (PB1a, PB3a and PB3b) or steroids (PB2c). Immunocytochemical studies demonstrated that the inducible isoenzymes of cytochrome P-450 are not distributed evenly throughout the hepatocyte population, and increasing concentrations of phenobarbitone or beta-naphthoflavone in the medium results in an increasing proportion of ‘induced’ cells. However, whereas maximal concentrations of beta-naphthoflavone resulted in virtually all cells containing induced levels of MC1b, a maximal concentration of phenobarbitone resulted in only 30% of the cells containing induced levels of PB3a/PB3b. These results are discussed in relation to the heterogeneous distribution and induction of cytochrome P-450 in the intact liver.

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2

Doostzadeh, J., and R. Morfin. "Effects of cytochrome P450 inhibitors and of steroid hormones on the formation of 7-hydroxylated metabolites of pregnenolone in mouse brain microsomes." Journal of Endocrinology 155, no. 2 (November 1, 1997): 343–50. http://dx.doi.org/10.1677/joe.0.1550343.

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Hydroxylations of pregnenolone (PREG) at the 7 alpha- and 7 beta-positions have been reported in numerous murine tissues and organs and responsible cytochrome P450 (CYP) species await identification. Using thin layer chromatography and gas chromatography-mass spectrometry, we report identification of 7 alpha-hydroxy-PREG and 7 beta-hydroxy-PREG metabolites produced in mouse brain microsome digests and kinetic studies of their production with apparent KM values of 0.5 +/- 0.1 microM and 5.1 +/- 0.6 microM for 7 alpha- and 7 beta-hydroxylation respectively. Investigation of CYP inhibitors and of steroid hormone effects on both 7 alpha- and 7 beta-hydroxylations of PREG showed that: (i) different CYP were involved in 7 alpha- and 7 beta-hydroxylation of PREG because solely 7 alpha-hydroxylation was extensively inhibited by metyrapone, alpha-naphthoflavone, ketoconazole and 3 beta-hydroxysteroids, (ii) CYP 1A2, 2D6, 2B1 and 2B11 were not responsible for 7 alpha- and 7 beta-hydroxylation of PREG because respective specific inhibitors furafylline, quinidine and chloramphenicol triggered no inhibition, (iii) CYP 1A1 was responsible for only part of the 7 beta-hydroxylation of PREG because use of alpha-naphthoflavone, which inhibits specifically CYP 1A1, did not suppress entirely 7 beta-hydroxylation, while ketoconazole, metyrapone and antipyrine, which do not inhibit CYP 1A1, decreased part of the 7 beta-hydroxylation, (iv) 7 alpha-hydroxylation of PREG may be shared with other 3 beta-hydroxysteroids such as isoandrosterone and 5-androstene-3 beta,17 beta-diol which were strong inhibitors, but not with dehydroepiandrosterone which was a non-competitive inhibitor as weak as 3-oxosteroids, and (v) 7 beta-hydroxylation of PREG was not markedly changed by other steroids. Taken together, these findings will be of use for identification of the CYP species responsible for 7 alpha- and 7 beta-hydroxylation of PREG and for studies of their activities in brain.

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3

Cantoni, L., M. Rizzardini, M. R. Cabello Porras, R. Carcano, M. Zappone, and M. Carelli. "Interferon beta reduces phenobarbital-and beta-naphthoflavone-mediated induction of cytochrome(s) P-450." Pharmacological Research 31 (January 1995): 364. http://dx.doi.org/10.1016/1043-6618(95)87715-0.

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4

Wilson, JM, MM Vijayan, CJ Kennedy, GK Iwama, and TW Moon. "beta-Naphthoflavone abolishes interrenal sensitivity to ACTH stimulation in rainbow trout." Journal of Endocrinology 157, no. 1 (April 1, 1998): 63–70. http://dx.doi.org/10.1677/joe.0.1570063.

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We report for the first time that beta-naphthoflavone (BNF) abolishes ACTH stimulation of cortisol production in rainbow trout (Oncorhynchus mykiss). There was significantly higher hepatic cytochrome P450 content and ethoxyresorufin O-de-ethylase and uridine-5'-diphosphoglucuronic acid transferase activities in BNF-treated fish than in sham-treated controls. BNF did not significantly affect either plasma turnover or tissue distribution of [3H]cortisol-derived radioactivity. Hepatic membrane fluidity and hepatocyte capacity for cortisol uptake were not altered by BNF as compared with the sham-treated fish. These results taken together suggest that BNF does not affect cortisol-clearance mechanisms in trout. A 3 min handling disturbance period elicited a plasma cortisol response in the sham-treated fish; however, the response in the BNF-treated fish was muted and significantly lower than in the sham fish. This in vivo response corroborates the lack of interrenal sensitivity to ACTH in vitro in the BNF-treated fish, suggesting that BNF affects the ACTH pathway in trout. Our results suggest the possibility that cytochrome P450-inducing compounds may affect cortisol dynamics by decreasing interrenal responsiveness to ACTH stimulation in fish, thereby impairing the physiological responses that are necessary for the animal to cope with the stressor.

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5

Hayashi, Hitomi, Eriko Taniai, Reiko Morita, Atsunori Yafune, Kazuhiko Suzuki, Makoto Shibutani, and Kunitoshi Mitsumori. "Threshold dose of liver tumor promoting effect of β-naphthoflavone in rats." Journal of Toxicological Sciences 37, no. 3 (2012): 517–26. http://dx.doi.org/10.2131/jts.37.517.

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6

Chatuphonprasert, Waranya, Thewtas Sangkawat, Nobuo Nemoto, and Kanokwan Jarukamjorn. "Suppression of beta-naphthoflavone induced CYP1A expression and lipid-peroxidation by berberine." Fitoterapia 82, no. 6 (September 2011): 889–95. http://dx.doi.org/10.1016/j.fitote.2011.05.002.

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7

Mohinta, Sonia, Gary Perdew, and Avery August. "Aryl Hydrocarbon Receptor independent production of IL-17A in a murine model of Hypersensitivity Pneumonitis (87.12)." Journal of Immunology 184, no. 1_Supplement (April 1, 2010): 87.12. http://dx.doi.org/10.4049/jimmunol.184.supp.87.12.

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Abstract AhR (Aryl hydrocarbon Receptor) is a cytosolic transcription factor functioning as a sensor for environmental toxins. Recently, AhR has been suggested to have a cardinal role in Th17 biology. Although AhR is not a direct regulatory factor for Th17 differentiation its activation is required for the functional differentiation of Th17 cells, and production IL-22. To study the role of AhR in T cell differentiation we have used selective ligands of AhR in an in vitro assay and found that AhR agonist beta-naphthoflavone enhances IL-17 production whereas an AhR inhibitor suppresses it, both at the level of transcription and translation. The Th2 cytokine IL-4 was suppressed by beta-naphthoflavone and induced by the inhibitor and the Th1 cytokine IFNγ was inhibited by both the compounds. To further investigate the role of AhR in Th17 biology we used a well established Th17 dominated murine model of hypersensitivity pneumonitis mediated by a thermophilic actinomycete Staphylopolyspora rectivirgula (SR). Analysis of the cytokine transcripts from the SR exposed lungs revealed that IL-17 was not only expressed in WT mice but was more highly expressed in Ahr-null mice. These data suggest that the AhR may regulate cytokine production by other T cell subsets, and that the requirement for the AhR in IL-17 expression may be restricted to T cells. Further work is required to determine the role of the AhR in the innate immune cells, which are potential sources of IL-17.

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8

Hsu, Sheng-Yao, Je-Wen Liou, Tsung-Lin Cheng, Shih-Yi Peng, Chi-Chen Lin, Yuan-Yuan Chu, Wei-Cheng Luo, Zheng-Kai Huang, and Shinn-Jong Jiang. "beta-Naphthoflavone protects from peritonitis by reducing TNF-alpha-induced endothelial cell activation." Pharmacological Research 102 (December 2015): 192–99. http://dx.doi.org/10.1016/j.phrs.2015.10.001.

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9

Smith, A. G., and J. E. Francis. "Chemically-induced formation of an inhibitor of hepatic uroporphyrinogen decarboxylase in inbred mice with iron overload." Biochemical Journal 246, no. 1 (August 15, 1987): 221–26. http://dx.doi.org/10.1042/bj2460221.

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An inhibitor of hepatic uroporphyrinogen decarboxylase (EC 4.1.1.37) was demonstrated in heat-treated extracts of livers from C57BL/10ScSn mice with iron overload after a single dose (100 mg/kg; 350 mumol/kg) of hexachlorobenzene (HCB). Inhibition was not due to accumulated uroporphyrin since this could be removed by a SEP-PAK C18 cartridge without affecting inhibitor activity. The presence of the inhibitor could be first demonstrated 2 weeks after mice received HCB and before major elevation of hepatic porphyrin levels. Maximum inhibitory potential was reached at about 8 weeks and was still detected 25 weeks after the chemical, thus paralleling the depression of enzyme activity reported previously [Smith, Francis, Kay, Greig & Stewart (1986) Biochem. J. 238, 871-878]. The inhibitor was not detected following treatment of mice with either iron or HCB alone or after the decarboxylase activity was destroyed in vitro by the combination of uroporphyrin and light. The formation of the inhibitor by inbred mouse strains nominally Ah-responsive (C57BL/6J, C57BL/10ScSn, BALB/c, C3H/HeJ, CBA/J and A/J) and Ah-nonresponsive (SWR, AKR, 129, SJL, LP and DBA/2) did not correlate fully with their reported Ah-phenotype. There was a correlation amongst the Ah-responsive strains only, with hepatic ethoxyphenoxazone de-ethylase activity induced in parallel experiments by treatment with beta-naphthoflavone. De-ethylase activity induced by HCB, however, was considerably less than that with beta-naphthoflavone, which has not been reported as porphyrogenic. Other polyhalogenated chemicals, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,4,2′,3′,4′-hexachlorobiphenyl and hexabromobenzene, also caused the formation of the inhibitor of uroporphyrinogen decarboxylase.

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10

Takanaga, Hiromi, Tomoko Yoshitake, Emi Yatabe, Shuntaro Hara, and Manabu Kunimoto. "beta-Naphthoflavone disturbs astrocytic differentiation of C6 glioma cells by inhibiting autocrine interleukin-6." Journal of Neurochemistry 90, no. 3 (August 2004): 750–57. http://dx.doi.org/10.1111/j.1471-4159.2004.02681.x.

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11

Heimark, L. D., and W. F. Trager. "Stereoselective metabolism of conformational analogs of warfarin by .beta.-naphthoflavone-inducible cytochrome P-450." Journal of Medicinal Chemistry 28, no. 4 (April 1985): 503–6. http://dx.doi.org/10.1021/jm00382a021.

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12

Grogan, W. M., V. M. Phillips, E. G. Schuetz, P. S. Guzelian, and C. O. Watlington. "Corticosterone 6 beta-hydroxylase in A6 epithelia: a steroid-inducible cytochrome P-450." American Journal of Physiology-Cell Physiology 258, no. 3 (March 1, 1990): C480—C488. http://dx.doi.org/10.1152/ajpcell.1990.258.3.c480.

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We found microsomal corticosterone 6 beta-hydroxylase (6 beta-OHase) from cultured A6 kidney epithelial cells to be a cytochrome P-450 enzyme with both similarities to and differences from the rat liver steroid 6 beta-OHase P-450p. Enzyme activity was inhibited by CO, alpha-naphthoflavone, metyrapone, and clotrimazole, well-known inhibitors of P-450 enzymes, and increased by known inducers of P-450 enzymes, including dilantin, phenobarbital sodium, and corticosteroids. Moreover, some additional, relatively specific inducers of P-450p (troleandomycin and pregnenolone-16 alpha-carbonitrile) also induced the A6 6 beta-OHase, whereas inducers of other forms of P-450 (aroclor, spironolactone, and isosafrole) appeared to repress the A6 enzyme. The time course of increase in enzyme activity and increased cellular cytochrome P-450 content were consistent with increased levels of enzyme protein. Induction of 6 beta-OHase by the substrate (corticosterone), the metabolite (6 beta-OH-corticosterone), dexamethasone, and aldosterone was biphasic as a function of inducer concentration, with approximate 50% effective concentration (EC50) values of 10(-8)-10(-9) M and 10(-5)-10(-6) M for the respective components of induction. Cortisol also induced the enzyme at 10(-8)-10(-6) M; however, its metabolite 6 beta-OH-cortisol was ineffective or decreased activity at higher concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

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13

Karimzadeh, Katayoon, and Asgar Zahmatkesh. "Biomarker responses in persian sturgeon (Acipenser persicus) exposed to benzo-a-pyrene and beta-naphthoflavone." Archives of Biological Sciences 65, no. 4 (2013): 1397–403. http://dx.doi.org/10.2298/abs1304397k.

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14

karimzadeh, katayoon. "Effects of Beta-Naphthoflavone and 3-Methylcholantheren on Biochemical Markers in Sturgeon Fish, Huso huso." Iranian Jornal of Toxicology 10, no. 3 (February 1, 2016): 13–17. http://dx.doi.org/10.29252/arakmu.10.3.13.

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15

Glöckner, R., and D. Müller. "Ethoxycoumarin O-deethylation (ECOD) activity in rat liver slices exposed to beta-naphthoflavone (BNF) in vitro." Experimental and Toxicologic Pathology 47, no. 4 (January 1995): 319–24. http://dx.doi.org/10.1016/s0940-2993(11)80271-x.

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16

Koleva, Milena R., and Tsanko S. Stoychev. "Effect of nifedipine, verapamil and diltiazem on the enzyme-inducing activity of phenobarbital and beta-naphthoflavone." General Pharmacology: The Vascular System 26, no. 1 (January 1995): 225–28. http://dx.doi.org/10.1016/0306-3623(94)e0044-m.

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17

Beije, B., and L. Möller. "Beta-naphthoflavone pretreatment reduces the genotoxic effect in rat liver by 2-nitrofluorene and 2-acetylaminofluorene." Mutation Research/Environmental Mutagenesis and Related Subjects 216, no. 5 (October 1989): 291. http://dx.doi.org/10.1016/0165-1161(89)90107-6.

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18

Lněničková, Kateřina, Lenka Skálová, Lucie Stuchlíková, Barbora Szotáková, and Petra Matoušková. "Induction of xenobiotic-metabolizing enzymes in hepatocytes by beta-naphthoflavone: Time-dependent changes in activities, protein and mRNA levels." Acta Pharmaceutica 68, no. 1 (March 1, 2018): 75–85. http://dx.doi.org/10.2478/acph-2018-0005.

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Abstract In the present study, time-dependency of the induction effect of a selective inducer on the activity, protein and mRNA levels of cytochromes P450 1A1/2 (CYP1A1/2), NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S-transferases (GSTA), in primary culture of rat hepatocytes was tested and evaluated. To show the differences in responses of tested enzymes, the common aryl hydrocarbon receptor (AhR) ligand agonist, beta-naphthoflavone (BNF), was used. Induction of CYP1A1/2 by BNF was detected at all time intervals and at all levels (i.e., mRNA, protein, enzyme activity). Different responses of NQO1 and GSTA upon BNF treatment were observed. Our results demonstrate that the responses of different xenobiotic-metabolizing enzymes to the inducer vary in time and depend on the measured parameter. For these reasons, an induction study featuring only one-time interval treatment and/ or one parameter testing could produce misleading information.

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19

Weimer, T. L. "Influence of beta-Naphthoflavone on 7,12-Dimethylbenz(a)anthracene Metabolism, DNA Adduction, and Tumorigenicity in Rainbow Trout." Toxicological Sciences 57, no. 2 (October 1, 2000): 217–28. http://dx.doi.org/10.1093/toxsci/57.2.217.

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20

Aubry, É., H. Rime, and G. Monod. "Beta-naphthoflavone inhibits the induction of hepatic oestrogen-dependent proteins by 17alpha-ethynylestradiol in mosquitofish (Gambusia holbrooki)." Biomarkers 10, no. 6 (January 2005): 439–55. http://dx.doi.org/10.1080/13547500500274248.

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21

Dasmahapatra, A. K., B. A. B. Wimpee, K. J. Budsberg, M. O. Dorschner, R. B. Phillips, and R. J. Hutz. "Lack of effect of beta-naphthoflavone on induction of Nramp genes in adult rainbow trout Oncorhynchus mykiss." Marine Environmental Research 50, no. 1-5 (July 2000): 147–51. http://dx.doi.org/10.1016/s0141-1136(00)00113-6.

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22

Popp, R., J. Bauersachs, M. Hecker, I. Fleming, and R. Busse. "A transferable, beta-naphthoflavone-inducible, hyperpolarizing factor is synthesized by native and cultured porcine coronary endothelial cells." Journal of Physiology 497, no. 3 (December 15, 1996): 699–709. http://dx.doi.org/10.1113/jphysiol.1996.sp021801.

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23

Ferreira, Roger Stacke, Cíntia da Cruz Chivittz, Guilherme Senna dos Santos, and Juliano Zanette. "Cytochrome P450 1A mRNA in the guppy Phalloceros caudimaculatus and response to beta-naphthoflavone and environmental samples." Aquatic Toxicology 181 (December 2016): 86–93. http://dx.doi.org/10.1016/j.aquatox.2016.10.023.

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24

Parola, M., M. E. Biocca, G. Leonarduzzi, E. Albano, M. U. Dianzani, K. S. Gilmore, D. J. Meyer, B. Ketterer, T. F. Slater, and K. H. Cheeseman. "Constitutive and inducible profile of glutathione S-transferase subunits in biliary epithelial cells and hepatocytes isolated from rat liver." Biochemical Journal 291, no. 2 (April 15, 1993): 641–47. http://dx.doi.org/10.1042/bj2910641.

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The constitutive and inducible cytosolic glutathione S-transferase (EC 2.5.1.18) subunit compositions of parenchymal cells (hepatocytes) and biliary epithelial cells (BEC) from rat liver have been quantitatively analysed using reverse-phase h.p.l.c. Hepatocytes, analysed in the absence of non-parenchymal cells, expressed constitutively the following subunits, in order of their concentration: 3, 4, 2, 1a, 1b, 8, 6 and 10. BEC express constitutively only four of the GST subunits expressed by hepatocytes and these are, in order of their concentration: subunits 2, 7, 4 and 3. Notable differences from hepatocytes are that BEC completely lack the Alpha-class subunits 1a and 1b that are major subunits in hepatocytes, Mu-class subunits make up a very low proportion of the total, and the Pi-class subunit 7 is a major subunit in BEC, whereas it is essentially absent from hepatocytes. For the first time, the effects of the inducing agents phenobarbitone (PB), beta-naphthoflavone (beta-NF) and ethoxyquin (EQ) have been characterized in a comprehensive and quantitative manner in both cell types. PB, beta-NF and EQ increased total GST protein in hepatocytes by approx. 2-fold, 3-fold and 4-fold respectively. Subunits significantly induced in hepatocytes were (in order of fold-induction): by PB, 1b > 8 > 3 > 2 > 4; by beta-NF, 1b > 8 > 2 > 3 > 4; and by EQ, 7 > 1b > 10 > 8 > 3 > 2 > 1a > 4. In BEC, neither PB nor beta-NF had significant effects on the total amount of GST protein, although PB did significantly induce subunit 3 at the expense of other subunits. EQ increased total GST protein nearly 5-fold in BEC, subunits 7 and 3 being induced dramatically above constitutive levels.

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25

Kessler, F. "Induction of a rat liver benzo[a]pyrene-trans-7,8-dihydrodiol glucuronidating activity by oltipraz and beta-naphthoflavone." Carcinogenesis 18, no. 1 (January 1, 1997): 107–14. http://dx.doi.org/10.1093/carcin/18.1.107.

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26

Shi, Lewis Zhichang, and Charles J. Czuprynski. "Beta-naphthoflavone causes an AhR-independent inhibition of invasion and intracellular multiplication of Listeria monocytogenes in murine hepatocytes." Microbial Pathogenesis 47, no. 5 (November 2009): 258–66. http://dx.doi.org/10.1016/j.micpath.2009.08.004.

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27

Müller, D., R. Glöckner, and M. Rost. "Monooxygenation, cytochrome P4501A1 and P4501A1-mRNA in rat liver slices exposed to beta-naphthoflavone and dexamethasone in vitro." Experimental and Toxicologic Pathology 48, no. 5 (July 1996): 433–38. http://dx.doi.org/10.1016/s0940-2993(96)80053-4.

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28

Cardenas-Vazquez, R., O. Yokosuka, and B. H. Billing. "Enzymic oxidation of unconjugated bilirubin by rat liver." Biochemical Journal 236, no. 3 (June 15, 1986): 625–33. http://dx.doi.org/10.1042/bj2360625.

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The presence of the enzyme bilirubin oxidase, which degrades bilirubin in vitro, was demonstrated in the liver. Subcellular-fractionation experiments indicate that bilirubin oxidase is located in both the inner and outer membranes of the mitochondria. The mean rate of the reaction is 1.57 +/- 0.38 (S.D.) nmol of bilirubin degraded/min per mg of mitochondrial protein (munits/mg of protein). With respect to the overall breakdown of bilirubin, the enzyme has a Km' of 136 microM-bilirubin and a Vmax.' of 9.13 munits/mg of protein. Its activity is influenced by the ionic strength of the media and is inhibited by KCN, thiol reagents, NADH and albumin. The enzyme is aerobic, and between 1 and 1.5 mol of O2 are consumed per mol of bilirubin degraded. The products of the reaction include propentdyopents. The hepatic bilirubin oxidase activity of the jaundiced Gunn-rat liver is not significantly different from that of the Sprague-Dawley rat, and it is not induced by beta-naphthoflavone.

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29

Pinto, Debora P., Cíntia C. Chivittz, Roger S. Ferreira, Mauricio S. Sopezki, and Juliano Zanette. "Beta-naphthoflavone-inducedCYP1A expression in the guppy Jenynsia multidentata: Time-dependent response, anesthetic MS-222 effect and fin analysis." Ecotoxicology and Environmental Safety 113 (March 2015): 38–44. http://dx.doi.org/10.1016/j.ecoenv.2014.11.023.

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30

Oyekan, A. O., J. C. McGiff, and J. Quilley. "Cytochrome P-450-dependent vasodilation of rat kidney by arachidonic acid." American Journal of Physiology-Heart and Circulatory Physiology 261, no. 3 (September 1, 1991): H714—H719. http://dx.doi.org/10.1152/ajpheart.1991.261.3.h714.

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Our previous studies indicated a role for cytochrome P-450-dependent enzymes in generating the mediators of the vasodilator effect of arachidonic acid (AA) in the preconstricted indomethacin-treated perfused kidney of the rat. We report that in vivo induction of cytochrome P-450 enzymes with 3-methylcholanthrene-beta-naphthoflavone or dexamethasone enhanced the renal vasodilator effect of AA in this experimental preparation. Conversely, depletion of cytochrome P-450 enzymes with stannous chloride or cobalt chloride diminished the vasodilator response to AA. Injection of AA resulted in the release of relaxant material into the renal effluent detected by superfusion of rabbit aortic rings. Inhibition of cytochrome P-450 with 7-ethoxyresorufin reduced the release of vasorelaxant material. Metabolism of labeled AA by the kidney revealed four peaks of radioactivity that were recovered from the renal effluent. The heights of these peaks were reduced by 7-ethoxyresorufin. These results provide further evidence for cytochrome P-450-dependent metabolism of AA to one or more vasodilator products by the rat kidney.

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31

Hayashi, Hitomi, Eriko Taniai, Reiko Morita, Masahiro Hayashi, Daichi Nakamura, Atsushi Wakita, Kazuhiko Suzuki, Makoto Shibutani, and Kunitoshi Mitsumori. "Enhanced liver tumor promotion but not liver initiation activity in rats subjected to combined administration of omeprazole and ^|^beta;-naphthoflavone." Journal of Toxicological Sciences 37, no. 5 (2012): 969–85. http://dx.doi.org/10.2131/jts.37.969.

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32

POMPON, Denis. "cDNA cloning and functional expression in yeast Saccharomyces cerevisiae of beta-naphthoflavone-induced rabbit liver P-450 LM4 and LM6." European Journal of Biochemistry 177, no. 2 (November 1988): 285–93. http://dx.doi.org/10.1111/j.1432-1033.1988.tb14375.x.

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33

Gao, Xiyu, Dewei He, Dianfeng Liu, Guiqiu Hu, Yufei Zhang, Tianyu Meng, Yingchun Su, et al. "Beta-naphthoflavone inhibits LPS-induced inflammation in BV-2 cells via AKT/Nrf-2/HO-1-NF-κB signaling axis." Immunobiology 225, no. 4 (July 2020): 151965. http://dx.doi.org/10.1016/j.imbio.2020.151965.

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34

Suzuki, Shugo, Kentaro Takeshita, Yuko Doi, Makoto Asamoto, Satoru Takahashi, Aya Naiki-Ito, and Tomoyuki Shirai. "2-Amino-3,8-Dimethylimidazo[4,5-f ]Quinoxaline (MeIQx)–Induced Hepatocarcinogenesis Is Not Enhanced by CYP1A Inducers, Alpha- and Beta-Naphthoflavone." Toxicologic Pathology 38, no. 4 (May 6, 2010): 583–91. http://dx.doi.org/10.1177/0192623310367808.

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35

Hapgood, J., S. Cuthill, P. Söderkvist, A. Wilhelmsson, I. Pongratz, R. H. Tukey, E. F. Johnson, J. A. Gustafsson, and L. Poellinger. "Liver cells contain constitutive DNase I-hypersensitive sites at the xenobiotic response elements 1 and 2 (XRE1 and -2) of the rat cytochrome P-450IA1 gene and a constitutive, nuclear XRE-binding factor that is distinct from the dioxin receptor." Molecular and Cellular Biology 11, no. 9 (September 1991): 4314–23. http://dx.doi.org/10.1128/mcb.11.9.4314-4323.1991.

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Dioxin stimulates transcription from the cytochrome P-450IA1 promoter by interaction with the intracellular dioxin receptor. Upon binding of ligand, the receptor is converted to a form which specifically interacts in vitro with two dioxin-responsive positive control elements located in close proximity to each other about 1 kb upstream of the rat cytochrome P-450IA1 gene transcription start point. In rat liver, the cytochrome P-450IA1 gene is marked at the chromatin level by two DNase I-hypersensitive sites that map to the location of the response elements and exist prior to induction of transcription by the dioxin receptor ligand beta-naphthoflavone. In addition, a DNase I-hypersensitive site is detected near the transcription initiation site and is altered in nuclease sensitivity by induction. The presence of the constitutive DNase I-hypersensitive sites at the dioxin response elements correlates with the presence of a constitutive, labile factor which specifically recognizes these elements in vitro. This factor appears to be distinct from the dioxin receptor, which is observed only in nuclear extract from treated cells. In conclusion, these data suggest that a certain protein-DNA architecture may be maintained at the response elements at different stages of gene expression.

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Hapgood, J., S. Cuthill, P. Söderkvist, A. Wilhelmsson, I. Pongratz, R. H. Tukey, E. F. Johnson, J. A. Gustafsson, and L. Poellinger. "Liver cells contain constitutive DNase I-hypersensitive sites at the xenobiotic response elements 1 and 2 (XRE1 and -2) of the rat cytochrome P-450IA1 gene and a constitutive, nuclear XRE-binding factor that is distinct from the dioxin receptor." Molecular and Cellular Biology 11, no. 9 (September 1991): 4314–23. http://dx.doi.org/10.1128/mcb.11.9.4314.

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Dioxin stimulates transcription from the cytochrome P-450IA1 promoter by interaction with the intracellular dioxin receptor. Upon binding of ligand, the receptor is converted to a form which specifically interacts in vitro with two dioxin-responsive positive control elements located in close proximity to each other about 1 kb upstream of the rat cytochrome P-450IA1 gene transcription start point. In rat liver, the cytochrome P-450IA1 gene is marked at the chromatin level by two DNase I-hypersensitive sites that map to the location of the response elements and exist prior to induction of transcription by the dioxin receptor ligand beta-naphthoflavone. In addition, a DNase I-hypersensitive site is detected near the transcription initiation site and is altered in nuclease sensitivity by induction. The presence of the constitutive DNase I-hypersensitive sites at the dioxin response elements correlates with the presence of a constitutive, labile factor which specifically recognizes these elements in vitro. This factor appears to be distinct from the dioxin receptor, which is observed only in nuclear extract from treated cells. In conclusion, these data suggest that a certain protein-DNA architecture may be maintained at the response elements at different stages of gene expression.

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Koponen, Kari, Ossi Ritola, Sirpa Huuskonen, Dan Linder, Katalin Monostory, and Pirjo Lindström-Seppä. "Intrastrain and interstrain variability in biotransformation enzyme activities of rainbow trout (Oncorhynchus mykiss)." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 12 (December 1, 1997): 2901–6. http://dx.doi.org/10.1139/f97-191.

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We assessed the intrastrain and interstrain variability of cytochrome P450 enzyme activities and conjugation reactions of different rainbow trout (Oncorhynchus mykiss) strains. The study protocol was divided into two parts: in two separate experiments, monooxygenase (7-ethoxyresorufin O-deethylase, EROD) and conjugation (glutathione S-transferase, GST; UDP-glucuronosyl transferase, UDPGT) enzyme activities were measured from liver and kidney samples of commonly used rainbow trout breeds. In the preliminary study, the differences in the basal biotransformation enzyme activities were detected in two separately cultivated rainbow trout strains. Results indicated significant intrastrain (UDPGT, GST) and interstrain (EROD) differences in biotransformation enzyme activities. In the experimental study, corresponding enzyme activities were measured from three different rainbow trout strains exposed to beta -naphthoflavone (BNF), a polycyclic aromatic hydrocarbon (PAH) type model compound.The results revealed significant interstrain differences, especially in hepatic EROD and GST\b activities. However, UDPGT activities in the liver, as well as the measured monooxygenase and conjugation activities in the kidney, showed no notable variance between strains.The present work addresses intrastrain differences between hatcheries and highlights the need for intercalibration of rainbow trout strains used in experimental studies in aquatic toxicology.

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Hsu, Sheng-Yao, Je-Wen Liou, Tsung-Lin Cheng, Shih-Yi Peng, Chi-Chen Lin, Yuan-Yuan Chu, Wei-Cheng Luo, Zheng-Kai Huang, and Shinn-Jong Jiang. "Corrigendum to “beta-Naphthoflavone protects from peritonitis by reducing TNF-alpha-induced endothelial cell activation” [Pharmacol. Res. 102 (2015) 192–199]." Pharmacological Research 104 (February 2016): 206. http://dx.doi.org/10.1016/j.phrs.2016.01.024.

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KAWAHARA, Shiro, Narisato HIRAI, Mitsuru ARAI, and Norihisa TATARAZAKO. "Effects of in vivo Combined Exposure of Japanese Medaka (Oryzias latipes) to a Proestrogen, trans-Stilbene, and a CYP1A Inducer, .BETA.-naphthoflavone." Journal of Environmental Chemistry 19, no. 3 (2009): 371–80. http://dx.doi.org/10.5985/jec.19.371.

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Szychowski, Konrad A., Kamila Rybczyńska-Tkaczyk, Jan Gmiński, and Anna K. Wójtowicz. "The interference of alpha- and beta-naphthoflavone with triclosan effects on viability, apoptosis and reactive oxygen species production in mouse neocortical neurons." Pesticide Biochemistry and Physiology 168 (September 2020): 104638. http://dx.doi.org/10.1016/j.pestbp.2020.104638.

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Bastien, Marie-Claude, and Jean-Pierre Villeneuve. "Characterization of cytochrome P450 2E1 activity by the [14C]nitrosodimethylamine breath test." Canadian Journal of Physiology and Pharmacology 76, no. 7-8 (July 1, 1998): 756–63. http://dx.doi.org/10.1139/y98-087.

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The objective of this study was to measure the rate of demethylation of nitrosodimethylamine in vivo in the rat and determine its value to assess CYP2E1 activity in intact animals. Nitrosodimethylamine labeled with 14C on both methyl groups was administered to rats and exhaled 14CO2 was collected during 2-3 h. The nitrosodimethylamine breath test was increased by inducers of CYP2E1, such as ethanol (+139%) and 4-methylpyrazole (+115%), and decreased by the inhibitor diallyl sulfide (-53%). In addition, the nitrosodimethylamine breath test was not changed significantly by inducers specific for other cytochrome P450 such as beta-naphthoflavone, dexamethasone, and phenobarbital. The specificity of the induction by 4-methylpyrazole and of the inhibition by diallyl sulfide for CYP2E1 was determined using the [14C]caffeine (CYP1A2), [14C]aminopyrine (CYP2C11), and [14C]erythromycin (CYP3A2) breath tests. 4-Methylpyrazole treatment caused a small increase of the caffeine (+33%) and aminopyrine (+9%) breath tests and no change of the erythromycin breath test. Diallyl sulfide treatment led to a small decrease of the caffeine breath test (-33%) and of the aminopyrine breath test (-13%) but a 23% increase of the erythromycin breath test. It is concluded that the [14C]nitrosodimethylamine breath test is useful to assess CYP2E1 activity in vivo in the rat.Key words: breath test, CYP2E1, nitrosodimethylamine.

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Bars, R. G., and C. R. Elcombe. "Dose-dependent acinar induction of cytochromes P450 in rat liver. Evidence for a differential mechanism of induction of P450IA1 by β-naphthoflavone and dioxin." Biochemical Journal 277, no. 2 (July 15, 1991): 577–80. http://dx.doi.org/10.1042/bj2770577.

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Rats received various doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), Aroclor 1254 (ARO), beta-naphthoflavone (BNF) or phenobarbital (PB), and the hepatic expression of cytochromes P450IA1 and/or P450IIB1/IIB2 was analysed by immunohistochemistry and Western blotting. A clear heterogeneous acinar induction of IA1 was detected when a low dose of TCDD, ARO or BNF was administered. When a low dose of TCDD or ARO was administered, IA1 was found to be induced primarily in hepatocytes located in acinus zone 3, whereas when a low dose of BNF was administered, IA1 was found to be preferentially induced in hepatocytes located in acinus zone 1. A clear zonal induction of IIB1/IIB2 was also observed when a low dose of PB or ARO was administered. Both compounds induced IIB1/IIB2 preferentially in hepatocytes located in acinus zone 3. When rats were administered high doses of TCDD, ARO, BNF or PB there was no zonal pattern of induction of IA1 or IIB1/IIB2; instead, a pan-acinar induction of these enzymes was observed. These results indicate that the overall hepatic concentration of IA1 or IIB1/IIB2 is merely dependent on the proportion of ‘induced hepatocytes’ within the acinus, which in turn depends on the dose of the inducer.

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Mohinta, Sonia, Avery August, and Gary Perdew. "Role of Aryl hydrocarbon receptor and the effect of selective AhR modulators on T cell differentiation (P1201)." Journal of Immunology 190, no. 1_Supplement (May 1, 2013): 50.43. http://dx.doi.org/10.4049/jimmunol.190.supp.50.43.

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Abstract The physiological role of AhR, particularly in immune response remains a key question after identification of AhR as an essential transcription factor for Th17 differentiation. Selective AhR modulators (SAhRMs) are a recently identified class of compounds that are capable of binding to AhR and repress cytokine- driven gene expression. These compounds are interesting therapeutically as they can be used to inhibit Dioxin Response Element (DRE)-mediated while inducing anti-inflammatory responses. Under non-skewing conditions, AhR agonist beta-naphthoflavone (BNF) enhances IL-17A production whereas SGA-360 an inhibitor suppresses it. Under Th17 skewing condition, AhR agonist BNF enhanced Th17 differentiation whereas AhR antagonist GNF and partial antagonist SGA-360 suppressed it. Interestingly, under Treg skewing condition the antagonists enhanced the Foxp3 expression, suggesting that such compounds have therapeutic potential in autoimmune disease by modulating the Th17/Treg balance. We have also examined AhR antagonists after disease development in a murine model of Th17 mediated disease, hypersensitivity pneumonitis mediated by Staphylopolyspora rectivirgula (SR). We find that these antagonists suppress AhR activity and induce IL-4, suggestive of a shift in T helper lineage. This suggests that SAhRMs may be useful in modulating AhR activation to regulate Th17/Treg balance, and that AhR selective ligands have potential for use as therapeutics in Th17 mediated diseases.

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Lee, Y., H. Kim, and J. Lee. "Molecular cloning and expression analysis of Gluttonous goby (Chasmichthys gulosus) liver cytochrome P450 1A (CYP1A) induced by PAHs (beta-naphthoflavone, benzo(a)pyrene)." Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 151, no. 1 (September 2008): S26. http://dx.doi.org/10.1016/j.cbpa.2008.05.099.

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Wang, Chun, Can-Xin Xu, Yiwen Bu, Kathleen M. Bottum, and Shelley A. Tischkau. "Beta-naphthoflavone (DB06732) mediates estrogen receptor-positive breast cancer cell cycle arrest through AhR-dependent regulation of PI3K/AKT and MAPK/ERK signaling." Carcinogenesis 35, no. 3 (October 26, 2013): 703–13. http://dx.doi.org/10.1093/carcin/bgt356.

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Raza, H., and N. G. Avadhani. "Hepatic mitochondrial cytochrome P-450 system. Purification and characterization of two distinct forms of mitochondrial cytochrome P-450 from beta-naphthoflavone-induced rat liver." Journal of Biological Chemistry 263, no. 19 (July 1988): 9533–41. http://dx.doi.org/10.1016/s0021-9258(19)76575-2.

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Yim, Bora, Hokyun Kim, Jisoo Kim, Haeyeon Kim, Eun-Ji Won, and Young-Mi Lee. "Identification and molecular characterization of cytochrome P450 (CYP450) family genes in the marine ciliate Euplotes crassus : The effect of benzo[ a ]pyrene and beta-naphthoflavone." Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology 196 (June 2017): 71–80. http://dx.doi.org/10.1016/j.cbpc.2017.03.012.

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Callaway, Danielle A., Weiwu Jiang, Lihua Wang, Krithika Lingappan, and Bhagavatula Moorthy. "Oxygen-mediated lung injury in mice lacking the gene for NRF2: Rescue with the cytochrome P4501A-inducer, beta-naphthoflavone (BNF), and differential sex-specific effects." Free Radical Biology and Medicine 160 (November 2020): 208–18. http://dx.doi.org/10.1016/j.freeradbiomed.2020.07.027.

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Morado, Claudio Nona, Magda Fernandes de Andrade-Tubino, Benjamin Carvalho Teixeira Pinto, and Francisco Gerson Araujo. "The Cichlidae fish Geophagus brasiliensis (Quoy & Gaimard, 1824) has suitability as a sentinel species for changes caused by xenobiotics?" Acta Scientiarum. Biological Sciences 44 (July 28, 2022): e59921. http://dx.doi.org/10.4025/actascibiolsci.v44i1.59921.

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Industrial wastewater and agricultural practices are among the main activities discharging organic pollutants, such as Polychlorinated biphenyl (PCB) congeners and organochlorine insecticides (e.g. DDT - dichloro diphenyl trichloroethane), to the environment. In this study, we used the native Cichlidae fish species Geophagus brasiliensis as a sentinel to evaluate the hepatic 7-ethoxyresorufin-O-deethylase EROD activity, a biomarker of exposure to CYP1A-inducing pollutants, to assess the bioavailability of xenobiotics in two reaches of a large lotic system in Southeast Brazil: a less disturbed area (site 1) in the upper stretch, and an area in the middle stretch, which receives various industrial and agricultural effluents from upstream cities (site 2). In addition, G. brasiliensis were exposed to a single dose of 50 mg kg-1 beta-naphthoflavone (BNF) or of 50 mg kg-1 dimethylbenzoanthracene (DMBA) to test the effects on, respectively, the hepatic EROD activity in S9 supernatant fraction, and the frequency of micronucleated erythrocytes three days after the i.p. treatments, and compared to an unexposed group, to test its potential as a sentinel for biomonitoring studies. The EROD activity was approximately two-fold higher in fish from the impacted stretches than in fish from the less disturbed stretches (p < 0.05). Micronuclei (MN) frequency was also significantly different (p < 0.01) in DMBA-treated fish. The induced EROD activity in the impacted site suggests that organochlorinated pollutants are reaching the biota of the Paraíba do Sul River, confirming the suitability of Geophagus brasiliensis as a useful sentinel species to detect changes caused by xenobiotics

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Strobel, Anneli, Roger Lille-Langøy, Helmut Segner, Patricia Burkhardt-Holm, Anders Goksøyr, and Odd André Karlsen. "Xenobiotic metabolism and its physiological consequences in high-Antarctic Notothenioid fishes." Polar Biology 45, no. 2 (December 26, 2021): 345–58. http://dx.doi.org/10.1007/s00300-021-02992-4.

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AbstractThe Antarctic ecosystem is progressively exposed to anthropogenic contaminants, such as polycyclic aromatic hydrocarbons (PAHs). So far, it is largely unknown if PAHs leave a mark in the physiology of high-Antarctic fish. We approached this issue via two avenues: first, we examined the functional response of the aryl hydrocarbon receptor (Ahr), which is a molecular initiating event of many toxic effects of PAHs in biota. Chionodraco hamatus and Trematomus loennbergii served as representatives for high-Antarctic Notothenioids, and Atlantic cod, Gadus morhua as non-polar reference species. We sequenced and cloned the Ahr ligand binding domain (LBD) of the Notothenioids and deployed a GAL4-based luciferase reporter gene assay expressing the Ahr LBD. Benzo[a]pyrene (BaP), beta-naphthoflavone and chrysene were used as ligands for the reporter gene assay. Second, we investigated the energetic costs of Ahr activation in isolated liver cells of the Notothenioids during acute, non-cytotoxic BaP exposure. In the reporter assay, the Ahr LBD of Atlantic cod and the Antarctic Notothenioids were activated by the ligands tested herein. In the in vitro assays with isolated liver cells of high-Antarctic Notothenioids, BaP exposure had no effect on overall respiration, but caused shifts in the respiration dedicated to protein synthesis. Thus, our study demonstrated that high-Antarctic fish possess a functional Ahr that can be ligand-activated in a concentration-dependent manner by environmental contaminants. This is associated with altered cost for cellular protein synthesis. Future studies have to show if the toxicant-induced activation of the Ahr pathway may lead to altered organism performance of Antarctic fish.

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