The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
F. Berthou - One of the best experts on this subject based on the ideXlab platform.
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CYP1A2 and 2E1 expression in rat liver treated with combined inducers (3-Methylcholanthrene and ethanol).
Biochemical and biophysical research communications, 1995Co-Authors: T. Goasduff, J.f. Menez, Y. Dreano, F. BerthouAbstract:The effects of combined ethanol and 3-Methylcholanthrene treatment on rat hepatic cytochrome CYP1A2 and CYP2E1 expression were evaluated. Such a treatment attempts to mimic the simultaneous consumption of ethanol and cigarette smoke. Treatments involving 3-Methylcholanthrene and combined ethanol + 3-Methylcholanthrene decreased both CYP2E1 expression at the mRNA level (0.6 and 0.4 fold versus controls, respectively) and protein level (0.6 and 0.9 fold versus controls, respectively), while dramatically increasing CYP1A2 expression. Furthermore, combined treatment provokes a synergistic induction of CYP1A2 expression as determined by its catalytic activity and protein content.
Nak Doo Kim - One of the best experts on this subject based on the ideXlab platform.
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Sex-related differences in rat hepatic cytochromes P450 expression following treatment with phenobarbital or 3-Methylcholanthrene
Archives of Pharmacal Research, 1992Co-Authors: Yoon Sook Lee, Sang Shin Park, Nak Doo KimAbstract:The induction of hepatic cytochromes P450 and metabolic effects have been examined in male and female Sprague-Dawley rats following treatment with either phenobarbital or 3-Methylcholanthrene. Hepatic cytochrome P450 levels were higher in males than in females by ≈40%. Treatment of male and female rats with phenobarbital or 3-Methylcholanthrene resulted in an ≈1.6- and 2-fold increase, respectively, in heptic microsomal cytochrome P450 levels in both sexes, relative to untreated animals. Immunoblot analyses were performed to compare sex-related changes in P450 levels. Hepatic P450IIB1 levels in males were greater than those in females following phenobarbital treatment. 3-Methylcholanthrene-induced male hepatic microsomes exhibited greater levels of P450 IA1 and IA2 than female microsomes, whereas uninduced microsomes from males or females failed to exhibit a band. Mab PCN 2-13-1 against P450IIIA recognized an intense band in uninduced hepatic microsomes from males whereas no band was recognized in uninduced microsomes from female rats. The levels of P450IIIA in males were increased 2 to 3-fold following treatment with phenobarbital. while the increase of IIIA levels in females by phenobarbital was minimal, as monitored by immunoblot analysis. Solid phase radioimmunoassay using monoclonal antibodies supported the results of immunoblot analysis. Phenobarbital treatment caused a 6.5-fold increase in the monoclonal antibody binding to IIB1 in males, whereas treatment of females with phenobarbital resulted in a 12-fold increase of IIB1 binding, relative to respective controls. The relative increase of IA levels by 3-Methylcholanthrene was also greater in females than in males (10-vs. 8-fold) although the levels of induced IA were comparable in both sexes, as assessed by radioimmunoassay. Radioimmunoassay also showed that hepatic IIE1 level was 1.5-fold higher in males than in females and that either phenobarbital or 3-Methylcholanthrene treatment caused 80% to 40% decrease in IIE1 levels, relative to control, in both sexes. Sex-related metabolic activities were examined in hepatic microsomes. Hexobarbital hydroxylase activity was 2- to 3-fold higher in uninduced microsomes from males than that from females. This hydroxylase activity was increased 2- and 3-fold in males and females, respectively, following phenobarbital treatment, as compared to controls. Addition of anti-P450IIB1 antibody to phenobarbital-induced hepatic microsomes from males and females produced 64% and 84% inhibition of hexobarbital oxidation, respectively. Aryl hydrocarbon hydroxylase activity was increased ≈12- and 26-fold in males and females. respectively, following 3-Methylcholanthrene treatment relative to controls. The anti-P450IA antibody inhibitable rate of aryl hydrocarbon hydroxylase activity was comparable in both sexes following 3-Methylcholanthrene treatment (≈70%). These results demonstrate that levels of hepatic P450IIB1 or P450IA are greater in male than in female for untreated, phenobarbital- or 3-Methylcholanthrene treated rats. In addition, the relative increase of P450IIB1 or IA by phenobarbital or 3-Methylcholanthrene is more significant in females.
T. Goasduff - One of the best experts on this subject based on the ideXlab platform.
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CYP1A2 and 2E1 expression in rat liver treated with combined inducers (3-Methylcholanthrene and ethanol).
Biochemical and biophysical research communications, 1995Co-Authors: T. Goasduff, J.f. Menez, Y. Dreano, F. BerthouAbstract:The effects of combined ethanol and 3-Methylcholanthrene treatment on rat hepatic cytochrome CYP1A2 and CYP2E1 expression were evaluated. Such a treatment attempts to mimic the simultaneous consumption of ethanol and cigarette smoke. Treatments involving 3-Methylcholanthrene and combined ethanol + 3-Methylcholanthrene decreased both CYP2E1 expression at the mRNA level (0.6 and 0.4 fold versus controls, respectively) and protein level (0.6 and 0.9 fold versus controls, respectively), while dramatically increasing CYP1A2 expression. Furthermore, combined treatment provokes a synergistic induction of CYP1A2 expression as determined by its catalytic activity and protein content.
Marvin A. Cuchens - One of the best experts on this subject based on the ideXlab platform.
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Effects of Pristane on Cytochrome P450 Isozyme Expression in Rat Tissues
International Journal of Environmental Research and Public Health, 2005Co-Authors: Carolyn B. Howard, Jacqueline Samuel, Shalonda B. Henderson, Paul E Thomas, Jacqueline J. Stevens, Marvin A. CuchensAbstract:Abstract: Chemical carcinogenesis studies are powerful tools to obtain information on potential mechanisms of chemical factors for malignancies. In this study Western blot analyses, using monoclonal antibodies specific for three different cytochrome P450 (CYP) isozymes (CYP1A1, CYP1A2 and CYP2B), were employed to examine the effect(s) of 3-Methylcholanthrene and/or pristane (2,6,10,14-tetramethylpentadecane) on the basal and inducible levels of expression of CYP proteins within Copenhagen rat tissues. Pristane exposure led to tissue specific differences in the CYP isozymes expressed and elicited increased CYP protein expression over 3-Methylcholanthrene induced levels in microsomes isolated from liver, Peyer's Patches, and thymus. Within the context of the chemical carcinogenesis model employed in this study, these observations correlated with the induction of B-cell malignancies by low doses of 3-Methylcholanthrene and of thymic lymphomas by a high 3-Methylcholanthrene dose. The data suggest that pristane treatment affects CYP isozyme expression. This pristane-mediated effect clearly could be a contributing factor in the chemical carcinogenesis of the previously observed lymphoid malignancies, and a possible basis for the tumor enhancing effects of pristane.
Yoon Sook Lee - One of the best experts on this subject based on the ideXlab platform.
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Sex-related differences in rat hepatic cytochromes P450 expression following treatment with phenobarbital or 3-Methylcholanthrene
Archives of Pharmacal Research, 1992Co-Authors: Yoon Sook Lee, Sang Shin Park, Nak Doo KimAbstract:The induction of hepatic cytochromes P450 and metabolic effects have been examined in male and female Sprague-Dawley rats following treatment with either phenobarbital or 3-Methylcholanthrene. Hepatic cytochrome P450 levels were higher in males than in females by ≈40%. Treatment of male and female rats with phenobarbital or 3-Methylcholanthrene resulted in an ≈1.6- and 2-fold increase, respectively, in heptic microsomal cytochrome P450 levels in both sexes, relative to untreated animals. Immunoblot analyses were performed to compare sex-related changes in P450 levels. Hepatic P450IIB1 levels in males were greater than those in females following phenobarbital treatment. 3-Methylcholanthrene-induced male hepatic microsomes exhibited greater levels of P450 IA1 and IA2 than female microsomes, whereas uninduced microsomes from males or females failed to exhibit a band. Mab PCN 2-13-1 against P450IIIA recognized an intense band in uninduced hepatic microsomes from males whereas no band was recognized in uninduced microsomes from female rats. The levels of P450IIIA in males were increased 2 to 3-fold following treatment with phenobarbital. while the increase of IIIA levels in females by phenobarbital was minimal, as monitored by immunoblot analysis. Solid phase radioimmunoassay using monoclonal antibodies supported the results of immunoblot analysis. Phenobarbital treatment caused a 6.5-fold increase in the monoclonal antibody binding to IIB1 in males, whereas treatment of females with phenobarbital resulted in a 12-fold increase of IIB1 binding, relative to respective controls. The relative increase of IA levels by 3-Methylcholanthrene was also greater in females than in males (10-vs. 8-fold) although the levels of induced IA were comparable in both sexes, as assessed by radioimmunoassay. Radioimmunoassay also showed that hepatic IIE1 level was 1.5-fold higher in males than in females and that either phenobarbital or 3-Methylcholanthrene treatment caused 80% to 40% decrease in IIE1 levels, relative to control, in both sexes. Sex-related metabolic activities were examined in hepatic microsomes. Hexobarbital hydroxylase activity was 2- to 3-fold higher in uninduced microsomes from males than that from females. This hydroxylase activity was increased 2- and 3-fold in males and females, respectively, following phenobarbital treatment, as compared to controls. Addition of anti-P450IIB1 antibody to phenobarbital-induced hepatic microsomes from males and females produced 64% and 84% inhibition of hexobarbital oxidation, respectively. Aryl hydrocarbon hydroxylase activity was increased ≈12- and 26-fold in males and females. respectively, following 3-Methylcholanthrene treatment relative to controls. The anti-P450IA antibody inhibitable rate of aryl hydrocarbon hydroxylase activity was comparable in both sexes following 3-Methylcholanthrene treatment (≈70%). These results demonstrate that levels of hepatic P450IIB1 or P450IA are greater in male than in female for untreated, phenobarbital- or 3-Methylcholanthrene treated rats. In addition, the relative increase of P450IIB1 or IA by phenobarbital or 3-Methylcholanthrene is more significant in females.