Induced Cytochrome P450 in Winter Flounder (Pseudopleuronectes americanus) from Coastal Massachusetts Evaluated by Catalytic Assay and Monoclonal Antibody Probes

1987 ◽  
Vol 44 (7) ◽  
pp. 1270-1277 ◽  
Author(s):  
John J. Stegeman ◽  
Frances Y. Teng ◽  
Elisabeth A. Snowberger
Keyword(s):  
Monoclonal Antibody ◽  
Cytochrome P450 ◽  
Liver Microsomes ◽  
Immunoblot Analysis ◽  
Environmental Chemicals ◽  
Winter Flounder ◽  
Boston Harbor ◽  
Pseudopleuronectes Americanus ◽  
Aryl Hydrocarbon ◽  
Environmental Induction

Levels of hepatic microsomal ethoxyresorufin O-deethylase (EROD) and aryl hydrocarbon hydroxylase (AHH) activities and sensitivity to inhibition by α-naphthoflavone in winter flounder (Pseudopleuronectes americanus) from Deer Island flats in Boston Harbor, off Plymouth Beach, off Nantucket, and at the outer New Bedford Harbor in Buzzards Bay, Massachusetts, suggested induction of cytochrome P450 by environmental chemicals. Levels of activity were higher in fish from Boston Harbor and Plymouth Bay than from Nantucket and Buzzards Bay. In fish from Buzzards Bay the levels of EROD and AHH activities were closely correlated, with some fish there apparently uninduced. Immunoblot analysis of flounder liver microsomes with a monoclonal antibody (1-12-3) against β-naphthofiavone-inducible scup cytochrome P450E revealed a single cross-reacting protein in untreated fish from all four field sites. A similar protein was induced by β-naphthoflavone treatment. Levels of this flounder protein correlated positively with levels of AHH and EROD activity in Buzzards Bay fish, consistent with a conclusion that some fish there were uninduced. The results demonstrate the induction of a P450E counterpart in flounder in Massachusetts waters and indicate its identity as the AHH and EROD catalyst. The results also establish the use of monoclonal anti-P450E in analysis of environmental induction.

scholarly journals Immunochemical evidence for multiple steroid-inducible hepatic cytochromes P-450 in the rat

1987 ◽  
Vol 245 (1) ◽  
pp. 27-33 ◽  
Author(s):  
K A Hostetler ◽  
S A Wrighton ◽  
P Kremers ◽  
P S Guzelian
Keyword(s):  
Monoclonal Antibody ◽  
Liver Microsomes ◽  
Immunoblot Analysis ◽  
Microsomal Protein ◽  
Female Rats ◽  
Regulatory Control ◽  
Male Rats ◽  
Terminal Amino Acid ◽  
Male And Female Rats ◽  
Terminal Amino

It has been established that there are glucocorticoid-inducible hepatic cytochromes P-450 in the rat (P-450p), the rabbit (LM3c) and man (HLp) which share extensive structural, functional and regulatory features. We prepared immunochemical probes to P-450p and identified a unique monoclonal antibody, 1G8, that recognizes purified P-450p, but neither purified LM3c nor HLp, on immunoblot analysis. The N-terminal amino acid sequence of purified samples of P-450p was identical with that previously reported for P-450PCN1 [Gonzalez, Nebert, Hardwick & Kasper (1985) J. Biol. Chem. 260, 7435-7441]. Immunoblot analyses of liver microsomes from untreated male rats revealed two 1G8-reactive proteins, whereas liver microsomes from untreated females contained none. Another monoclonal antibody, 13-7-10, reacted specifically with LM3c and HLp, but not with P-450p. A single 13-7-10-reactive microsomal protein was detected in untreated male and female rats, the latter protein exhibiting a greater apparent Mr. 1G8-reactive proteins were induced to the greatest extent by triacetyloleandomycin, followed by dexamethasone, chlordane, pregnenolone-16 alpha-carbonitrile and 2,4,2′,4′-tetrachlorobiphenyl. In contrast, 13-7-10-reactive proteins were most strongly induced by dexamethasone, only moderately by triacetyloleandomycin and pregnenolone-16 alpha-carbonitrile, weakly by chlordane and not at all by 2,4,2′,4′-tetrachlorobiphenyl. We conclude that the P-450p family in rat liver consists of three or more proteins that are structurally related and yet appear to be under distinct regulatory control.

Inhibition of Cytochrome P450 3A1/2 by Organotin Compound Di-N-Butyl-(4-chlorobenzohydroxamato)tin (IV) Chloride in Rat Liver and BRL Cells

2011 ◽  
Vol 356-360 ◽  
pp. 681-687
Author(s):  
Yun Xia Zhang ◽  
Yun Lan Li ◽  
Qing Shan Li
Keyword(s):  
Cytochrome P450 ◽  
Rat Liver ◽  
Biological Activities ◽  
Liver Microsomes ◽  
Immunoblot Analysis ◽  
Organotin Compound ◽  
Control Group ◽  
Rat Liver Microsomes ◽  
New Paradigm ◽  
Blank Control Group

Organotin compounds are high toxiferous chemicals and ubiquitous in our environment, which also have high biological activities. Di-n-butyl-(4-chlorobenzohydroxamato)tin (IV) chloride (DBDCT) represents a new paradigm for tin-based antitumor complexes with high activity. The inhibitory effect of DBDCT on cytochrome P450 3A(CYP3A) was studied in this article. The adult male SD rats were randomly divided into five groups with six in each and treated separately with saline, lipopolysaccharide (LPS, 5mg/kg), DBDCT (1.25, 2.5 and 5.0mg/kg, respectively) intraperitoneally for 2 days after induced with dexamethasone (DEX) at a dose of 100mg/kg for 4 days. The cytochrome P450 (CYP450) content was assayed by the method of Omura and Santa after the protein concentration detected by BCA assay kit. The activity of CYP3A was determined by the method of Nash. Western blot analysis was used to detect the expression of CYP3A1/2 at protein level in rat liver microsomes and Buffalo Rat Liver (BRL) cells. The results demonstrated that the activity of CYP450 and CYP3A were inhibited by exposure to DBDCT in rat liver compared with that of the blank control group. The expression of CYP3A1 and CYP3A2 proteins in rats treated with 1.25, 2.5 and 5.0mg/kg DBDCT were down-regulated respectively by 22.8% (p<0.01),24.3%(p<0.01), 58.4%(p<0.001) and 37.6%(p<0.001), 41.4%(p<0.001), 49.2%(p<0.001), than that of the blank control group. Immunoblot analysis of protein from BRL cell lysate demonstrated that the expression of CYP3A1 and CYP3A2 protein reduced separately by 11.4% (p<0.05), 34.2%(p<0.001), 45.5%(p<0.001), 64.9%(p<0.001), 78.8%(p<0.001) and 12.8% (p<0.05), 9.9% (p<0.05), 28.0% (p<0.001), 24.9% (p<0.001), 34.2% (p<0.001) after treated with DBDCT at a dose of 1µmol/L (for 24, 36, 48h) and 2µmol/L(for 24 and 48h). The activity of CYP3A in rat liver microsomes was decreased remarkably compared with that of the blank control group. Immunoblot analysis showed that the expression of CYP3A1/2 was inhibited significantly by DBDCT in rat liver and BRL cells.

Ultrastructure of vacuolated cells in the liver of rock sole and winter flounder living in contaminated environments

1990 ◽  
Vol 48 (3) ◽  
pp. 522-523
Author(s):  
Carla Stehr
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Puget Sound ◽  
Light And Electron Microscopy ◽  
Similar Type ◽  
Winter Flounder ◽  
Boston Harbor ◽  
Liver Lesions ◽  
Pseudopleuronectes Americanus ◽  
Vacuolated Cells

Focal and diffuse areas of nonneoplastic vacuolated cells in the liver have been observed with light microscopy in up to 12% of the demersal rock sole (Lepidopsetta bilineata) inhabiting Eagle Harbor, which is a contaminated bay in Puget Sound. A similar type of liver vacuolation has also been observed at higher prevalences in winter flounder (Pseudopleuronectes americanus) inhabiting contaminated areas of Boston Harbor. This paper compares the ultrastructure of vacuolated liver lesions in feral rock sole with that of winter flounder from contaminated areas of Puget Sound and Boston Harbor, respectively.Rock sole from Eagle Harbor, Puget Sound, and winter flounder from Boston Harbor, were collected by bottom trawl from NOAA research vessels. Fish were killed and immediately necropsied. Adjacent pieces of tissue were collected for light and electron microscopy from grossly visible liver lesions or from the center of the liver. Samples collected for histology were fixed in Dietrich's solution, embedded in paraffin and stained with H&E.

Biochemical Evidence that Winter Flounder (Pseudopleuronectes americanus) have Induced Hepatic Cytochrome P-450-Dependent Monooxygenase Activities

1983 ◽  
Vol 40 (7) ◽  
pp. 854-865 ◽  
Author(s):  
Gary L. Foureman ◽  
Nathaniel B. White Jr. ◽  
John R. Bend
Keyword(s):  
Body Weight ◽  
Liver Microsomes ◽  
Weight Ratio ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Body Weight Ratio ◽  
Monooxygenase Activity ◽  
Hepatic Microsomes ◽  
Desert Island ◽  
Cytochrome P 450

Livers from winter flounder (Pseudopleuronectes americanus) captured near Mount Desert Island, Maine, showed marked variation in hepatic benzo[a]pyrene hydroxylase (AHH; from 0.04 to 8.8 FU∙min−1∙mg protein−1) and 7-ethoxyresorufin deethylase activities (7-ERD; from < 2 to 1165 pmol∙min−1∙mg protein−1), and a dichotomy in the effect of 7,8-benzoflavone (ANF) added in vitro on AHH activity. Based on this ANF effect, the flounder could be divided into two groups. One group had high 7-ERD activity and high AHH activity which was inhibited by ANF; the other group had low 7-ERD activity and low AHH activity which was enhanced by ANF. Sex, weight, length, liver weight, gonad weight/body weight ratio, and liver/body weight ratio explained only a small part of the variability in hepatic AHH activities. Electrophoretograms of hepatic microsomes from flounder treated with 1,2,3,4-dibenzanthracene (DBA) or 5,6-benzoflavone (βNF) showed a novel or enriched polypeptide species present near 57 000 daltons, in the molecular weight (MW) range of known cytochrome P-450 isozymes. A polypeptide of similar MW was only faintly discernable in liver microsomes from untreated flounder whose hepatic AHH activity was much lower than that of the treated flounder, whereas a band of this MW was prominent in hepatic microsomes from untreated flounder with high hepatic AHH activity. These results suggest that many of the winter flounder captured near Mount Desert Island, Maine have induced hepatic monooxygenase activity due to exposure to PAH or PAH-like inducers present in their natural habitat.

Deactivation of anti-cancer drug letrozole to a carbinol metabolite by polymorphic cytochrome P450 2A6 in human liver microsomes

Xenobiotica ◽  
2009 ◽  
Vol 00 (00) ◽  
pp. 090901052053001-8
Author(s):  
K. Murai ◽  
H. Yamazaki ◽  
K. Nakagawa ◽  
R. Kawai ◽  
T. Kamataki
Keyword(s):  
Cytochrome P450 ◽  
Human Liver ◽  
Liver Microsomes ◽  
Human Liver Microsomes ◽  
Cancer Drug ◽  
Anti Cancer ◽  
Cytochrome P450 2A6

Selegiline Metabolism and Cytochrome P450 Enzymes:In vitro Study in Human Liver Microsomes*

2000 ◽  
Vol 86 (5) ◽  
pp. 215-221 ◽  
Author(s):  
Paivi Taavitsainen ◽  
Markku Anttila ◽  
Leena Nyman ◽  
Hari Karnani ◽  
Jarmo S. Salonen ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Human Liver ◽  
Liver Microsomes ◽  
Human Liver Microsomes ◽  
Vitro Study
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