In vitro and in vivo studies of the effect of vitamin E on microsomal cytochrome P450 in rat liver

1991 ◽  
Vol 42 (11) ◽  
pp. 2107-2114 ◽  
Author(s):  
Michael Murray
Keyword(s):  
Cytochrome P450 ◽  
Vitamin E ◽  
Rat Liver ◽  
In Vivo Studies ◽  
Microsomal Cytochrome ◽  
Microsomal Cytochrome P450

In vitro biotransformation of atrazine by rat liver microsomal cytochrome P450 enzymes

1998 ◽  
Vol 116 (3) ◽  
pp. 181-198 ◽  
Author(s):  
Nobumitsu Hanioka ◽  
Hideto Jinno ◽  
Ken Kitazawa ◽  
Toshiko Tanaka-Kagawa ◽  
Tetsuji Nishimura ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Rat Liver ◽  
Cytochrome P450 Enzymes ◽  
Microsomal Cytochrome ◽  
Microsomal Cytochrome P450

scholarly journals In vivo study of the effect of antiviral acyclic nucleotide phosphonate (R)-9-[2- (phosphonomethoxy) propyl]adenine (PMPA, tenofovir) and its prodrug tenofovir disoproxil fumarate on rat microsomal cytochrome P450

2008 ◽  
pp. 761-768
Author(s):  
E Anzenbacherová ◽  
P Anzenbacher ◽  
Z Zídek ◽  
E Buchar ◽  
E Kmoníčková ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Rat Liver ◽  
Relative Proportion ◽  
Antiviral Agent ◽  
Total Content ◽  
Repeated Administration ◽  
Microsomal Protein ◽  
Microsomal Cytochrome ◽  
Microsomal Cytochrome P450

The total content of rat liver microsomal cytochrome P450 (CYP) significantly decreased after repeated i.p. administration of the antiviral agent tenofovir ((R)-9-[2-(phosphonomethoxy)propyl] adenine) and tenofovir disoproxil at a daily dose 25 mg/kg, although the content of liver microsomal protein did not change. The decrease of the CYP content was accompanied by concomitant increase of the amount of inactive CYP form, cytochrome P420. This effect was confirmed by a parallel study of the activities of selected CYP forms, CYP2E1 (p-nitrophenol hydroxylation) and CYP1A2 (7-ethoxyresorufin deethylation). The activity (expressed relatively to the protein content) of both CYP forms decreased significantly following the decrease of the total CYP. On the other hand, the CYP2E1 activity expressed relatively to the decreasing total CYP content remained unchanged. However, CYP1A2 activity also decreased when calculated relatively to the total native CYP content indicating lower stability of this form. Semiquantitative RT-PCR showed no significant changes in expression of major rat liver microsomal CYP forms after tenofovir treatment. In conclusion, repeated administration of tenofovir in higher doses led to significant decrease of the relative proportion of active liver microsomal CYPs accompanied by a conversion of these enzymes to the inactive form (CYP420) maintaining the sum of CYP proteins unchanged.

scholarly journals Effect of 4-(4-Chlorobenzyl)pyridine on Rat Hepatic Microsomal Cytochrome P450 and Drug-Metabolizing Enzymes in Vivo and in Vitro.

2001 ◽  
Vol 24 (5) ◽  
pp. 505-509 ◽  
Author(s):  
Yasuna KOBAYASHI ◽  
Naomi OHSHIRO ◽  
Tadanori SASAKI ◽  
Shogo TOKUYAMA ◽  
Takashi TOBE ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Drug Metabolizing Enzymes ◽  
Metabolizing Enzymes ◽  
Microsomal Cytochrome ◽  
Microsomal Cytochrome P450

In vivo and in vitro effects of helenalin on mouse hepatic microsomal cytochrome P450

1991 ◽  
Vol 41 (2) ◽  
pp. 229-235 ◽  
Author(s):  
Dennis E. Chapman ◽  
David J. Holbrook ◽  
Stephen G. Chaney ◽  
Iris H. Hall ◽  
Lee Kuo-Hsiung
Keyword(s):  
Cytochrome P450 ◽  
Microsomal Cytochrome ◽  
Microsomal Cytochrome P450 ◽  
In Vitro Effects

scholarly journals Which cytochrome P450 metabolizes phenazepam? Step by step in silico, in vitro, and in vivo studies

2018 ◽  
Vol 33 (2) ◽  
pp. 65-73 ◽  
Author(s):  
Dmitriy V. Ivashchenko ◽  
Anastasia V. Rudik ◽  
Andrey A. Poloznikov ◽  
Sergey V. Nikulin ◽  
Valeriy V. Smirnov ◽  
...  
Keyword(s):  
Cell Culture ◽  
Cytochrome P450 ◽  
In Silico ◽  
In Vivo Studies ◽  
Cyp3a Activity ◽  
Cell Culture Study ◽  
Study Results ◽  
Three Stages

Abstract Background: Phenazepam (bromdihydrochlorphenylbenzodiazepine) is the original Russian benzodiazepine tranquilizer belonging to 1,4-benzodiazepines. There is still limited knowledge about phenazepam’s metabolic liver pathways and other pharmacokinetic features. Methods: To determine phenazepam’s metabolic pathways, the study was divided into three stages: in silico modeling, in vitro experiment (cell culture study), and in vivo confirmation. In silico modeling was performed on the specialized software PASS and GUSAR to evaluate phenazepam molecule affinity to different cytochromes. The in vitro study was performed using a hepatocytes’ cell culture, cultivated in a microbioreactor to produce cytochrome P450 isoenzymes. The culture medium contained specific cytochrome P450 isoforms inhibitors and substrates (for CYP2C9, CYP3A4, CYP2C19, and CYP2B6) to determine the cytochrome that was responsible for phenazepam’s metabolism. We also measured CYP3A activity using the 6-betahydroxycortisol/cortisol ratio in patients. Results: According to in silico and in vitro analysis results, the most probable metabolizer of phenazepam is CYP3A4. By the in vivo study results, CYP3A activity decreased sufficiently (from 3.8 [95% CI: 2.94–4.65] to 2.79 [95% CI: 2.02–3.55], p=0.017) between the start and finish of treatment in patients who were prescribed just phenazepam. Conclusions: Experimental in silico and in vivo studies confirmed that the original Russian benzodiazepine phenazepam was the substrate of CYP3A4 isoenzyme.

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