Metabolism by cytochromes P450 (P450) is highly inefficient as the oxidation of substrate is associated with the production of varying proportions of hydrogen peroxide and/or superoxide. (nih.gov)
Tsyrlov used protonophores and probes affecting arachidonic acid of phospholipids in endoplasmic reticulum to show different compartmentalized hydrobobic clusters coupled with substrate-binding and electron-accepting moieties of membrane bound cytochrome P450 (CYP). (wikipedia.org)
Using a randomized crossover design, we examined the effect of various vegetable diets on cytochrome P450 (CYP) 1A2, N-acetyltransferase 2 (NAT2) and xanthine oxidase activity in humans. (nih.gov)
To determine the influence of Echinacea purpurea on the pharmacokinetics of lopinavir-ritonavir and on cytochrome P450 (CYP) 3A and P-glycoprotein activity by using the probe substrates midazolam and fexofenadine, respectively. (nih.gov)
Effect of sex and menstrual cycle phase on cytochrome P450 2C19 activity with omeprazole used as a biomarker. (childrensmercy.org)
Discovery of a novel nonfunctional cytochrome P450 2D6 allele, CYP2D642, in African American subjects. (childrensmercy.org)
Activities of cytochrome P450 1A2, N-acetyltransferase 2, xanthine oxidase, and cytochrome P450 2D6 are unaltered in children with cystic fibrosis. (childrensmercy.org)
Maribavir pharmacokinetics and the effects of multiple-dose maribavir on cytochrome P450 (CYP) 1A2, CYP 2C9, CYP 2C19, CYP 2D6, CYP 3A, N-acetyltransferase-2, and xanthine oxidase activities in healthy adults. (childrensmercy.org)
The UK manufacturers of ritonavir predict that it may raise levels of SSRIs (fluoxetine, paroxetine, sertraline) due to inhibitory effect of ritonavir on cytochrome P450 isoenzymes CYP2D6 (See reference number 5). (vibore.com)
Gutierrez,MM, Rosenberg J, Abramowitz W. An evaluation of the potential for pharmacokinetic interaction between escitalopram and the cytochrome P450 3A4 inhibitor ritonavir. (vibore.com)
The apparent reason for all these changes is that cimetidine inhibits activity of cytochrome P450 so that metabolism of SSRIs is reduced, and as a result their serum levels rise. (vibore.com)
Dissolution studies with ginger extract conducted in biorelevant simulated intestinal fluid yielded (S)-6-gingerol and 6-shogaol concentrations that could conceivably exceed cytochrome P450 (CYP) IC50 values when consumed in recommended doses. (bvsalud.org)
Several of the polychlorinated biphenyls (PCBs), i.e. the dioxin-like PCBs, are known to induce the P450 enzymes CYP1A1, CYP1A2 and CYP1B1 by activating the aryl hydrocarbon receptor (Ah)-receptor. (ox.ac.uk)
It is metabolized in the liver, involving the cytochrome P450 (CYP3A4) isoform CYP3A4, and is characterized by a narrow therapeutic window, dose-dependent toxicity and high inter-individual and intra-individual variability. (mdpi.com)
In phase I, oxidation, hydrolysis, reduction, and cyclization reactions are catabolized mainly by the cytochrome P450 (CYP450) superfamily of monooxygenase enzymes. (biomedcentral.com)
Sequencing of the tumor DNA as well as further mechanistic studies provided evidence that PAHs initiate carcinogenesis by inducing mutations primarily in the Ha-Ras oncogene and that this process requires a metabolic conversion of the per se non-toxic chemicals to highly reactive metabolites, a process which is primarily carried out by AHR-regulated cytochrome P450 (CYP) monooxygenases ( 10 - 12 ). (frontiersin.org)
CYP1A13
In humans, CYP1A2 has been detected primarily in the liver, in contrast to the closely related CYP1A1, which is expressed in extrahepatic tissues such as lung, placenta, and lymphocytes ( Kawajiri 1999 ). (nih.gov)
Like CYP1A1, CYP1A2 is thought to be induced by exposure to xenobiotics such as 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD), polychlorinated biphenyls (PCBs), and other structurally related chemicals that have the ability to bind to the aryl hydrocarbon (Ah) receptor. (nih.gov)
In the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study (1016 subjects all aged 70), 21 SNPs in the CYP1A1, CYP1A2 and CYP1B1 genes were genotyped. (ox.ac.uk)
Enzymes5
Following up discovery of mechanism for "phenobarbital-type" induction of CYP2B6 and applicability of induced-fit hypothesis for membrane-bound enzymes, Tsyrlov with Konstantin Gerasimov prioritized method how to convert first-line antipyretic and antimalarial medicines into their long-acting forms. (wikipedia.org)
Induction or inhibition of biotransformation enzymes, enzymes that activate or detoxify numerous xenobiotics, is one mechanism by which vegetables may alter cancer risk. (nih.gov)
Although our lab between 1975 and 1980 had published several lines of evidence in mouse and rabbit, showing that P1-450 and P-448 were enzymes derived from separate genes, it was not until we had the cDNA sequences in hand (1981-84) that most competitors were convinced that we had been correct all along. (sciencewatch.com)
Cytochrome P 450 (CYP) enzymes have the potential to affect colorectal cancer (CRC) risk by determining the genotoxic impact of exogenous carcinogens and levels of sex hormones. (biomedcentral.com)
Lavender oil showed weak inhibitory effect on the catalytic activity of CYP3A4 and CYP1A2 enzymes (IC50 12.0 and 21.5 µg/mL). (bvsalud.org)
Enzyme3
The effects of HO-1 induction were less dramatic in the absence of substrate for CYP1A2, suggesting that the enzyme was more effective in inhibiting the CYP1A2-related activity than the CPR-related production of superoxide (that dismutates to form hydrogen peroxide). (nih.gov)
Cytochrome P-450 1A2 (CYP1A2) is an enzyme involved in the metabolic activation of some carcinogens and is believed to be induced by xenobiotics. (nih.gov)
The genotoxic impact of carcinogen exposure is heavily influenced by a complex array of metabolic pathways, which includes the cytochrome P 450 (CYP) enzyme system. (biomedcentral.com)
Metabolism3
HO-1 induction was associated with slower rates of metabolism of the CYP1A2-specific substrate, 7-ethoxyresorufin. (nih.gov)
Several cytochrome P-450 isozymes are involved in the metabolism of benzene, although the predominant form is CYP2E1 (Gut et al. (cdc.gov)
We conclude that glyphosate-dependent inhibition of soybean leaf metabolism leads to the induction of defense proteins without sustained oxidation. (ban-glyphosate.com)
Caffeine1
At the Mohawk Nation at Akwesasne (in New York and in Ontario and Quebec, Canada), 103 adults were interviewed, and they donated blood for serum PCB analysis and underwent the caffeine breath test (CBT), a safe and noninvasive procedure that uses caffeine as a probe for CYP1A2 activity in vivo . (nih.gov)
CYP3A42
To investigate if common variants of CYP1A2, CYP1B1, CYP3A4, CYP3A5, CYP11A1, CYP17A1 and CYP19A1 influence CRC risk we genotyped 2,575 CRC cases and 2,707 controls for 20 single nucleotide polymorphisms (SNPs) that have not previously been shown to have functional consequence within these genes. (biomedcentral.com)
In the present study, we have investigated the relationship between single nucleotide polymorphisms (SNP) in CYP1A2, CYP1B1, CYP3A4, CYP3A5, CYP11A1, CYP17A1 and CYP19A1 and CRC risk in a large study of 2,575 cases and 2,707 controls. (biomedcentral.com)
CYP1B14
There was a suggestion of increased risk, albeit insignificant after correction for multiple testing, of CRC for individuals homozygous for CYP1B1 rs162558 and heterozygous for CYP1A2 rs2069522 (odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.03-1.80 and OR = 1.34, 95% CI: 1.00-1.79 respectively). (biomedcentral.com)
This study provides some support for polymorphic variation in CYP1A2 and CYP1B1 playing a role in CRC susceptibility. (biomedcentral.com)
However, there were several additional SNPs in the CYP1A2 and CYP1B1 that showed nominally significant associations with PCB118 levels (p-values in the 0.003-0.05 range). (ox.ac.uk)
Genetic variation in CYP1A2 and CYP1B1 might also be associated with other PCBs. (ox.ac.uk)
Isozymes1
Cytochrome P-450 1A2 (CYP1A2) is a member of the cytochrome P-450 superfamily of isozymes. (nih.gov)
Superfamily1
The cytochrome superfamily consists of nearly 60 members in humans (Human Genome Project 2013), which may be expressed differently in individual cells when challenged by xenobiotics, leading to cellular heterogeneity that remains concealed in a bulk analysis. (biomedcentral.com)
CYP2D63
Side‑chain oxidation is mediated mainly by CYP1A2 and to some extent by CYP2D6. (nih.gov)
Identification and characterization of novel sequence variations in the cytochrome P4502D6 (CYP2D6) gene in African Americans. (childrensmercy.org)
Cytochrome P4502D6 (CYP2D6) gene locus heterogeneity: characterization of gene duplication events. (childrensmercy.org)
Microsomal2
The inhibition associated with HO-1 induction was not dependent on the addition of heme to the microsomal incubations. (nih.gov)
Tsyrlov has authored 4 monographs, and co-authored over 280 publications on microsomal, purified and recombinant monooxygenases, and mechanisms of CYP induction by xenobiotics. (wikipedia.org)
Induces1
These results demonstrate that while one vegetable subgroup induces human CYP1A2 activity, another subgroup inhibits it. (nih.gov)
Substrates1
Whereas CYP1A2 can metabolize PAHs to a small extent, N -arylamines are the principle substrates for CYP1A2. (sciencewatch.com)
Liver3
Liver microsomes were isolated from uninduced rats and rats that were treated with cadmium and/or β-napthoflavone (BNF) to induce HO-1 and/or CYP1A2. (nih.gov)
1988). Benzene is initially metabolized by cytochrome P-450-dependent mixed function oxidases primarily in the liver via several toxification and detoxification (via conjugation) pathways. (cdc.gov)
Relevant of mutagenicity and clastogenici- angiosarcomas of the liver, which carcinogens discussed in this chap- ty, including the induction of sister are rare tumours, were identified in ter do not include pharmaceutical chromatid exchange (SCE), chro- humans, rats, and mice exposed to drugs classified in Group 1, which mosomal aberrations (CA), and mi- vinyl chloride. (who.int)
Oxidation1
Tsyrlov revealed that human CYP1A2 is the catalyst of ethanol and uroporphyrinogen oxidation. (wikipedia.org)
Humans3
Very few studies, however, have investigated the association between environmental exposures and in vivo CYP1A2 activity in humans. (nih.gov)
The results support the notion that CYP1A2 activity may be a marker of an early biological effect of exposure to PCBs in humans and that the CBT may be a useful tool to monitor such effects. (nih.gov)
Very few studies have investigated in vivo CYP1A2 activity in humans exposed to TCDD, PCBs, or related chemicals, and the results have been contradictory. (nih.gov)
Transporters1
We evaluated the ability of a well-characterized ginger extract, and several of its phytoconstituents, to activate select nuclear receptors as well as modulate the activity of various cytochrome P450s and ATP-binding cassette (ABC) transporters because phytochemical-mediated modulation of these proteins underlies many clinically relevant herb-drug interactions (HDI). (bvsalud.org)
Activity2
To address this issue, a study was conducted of CYP1A2 activity among Native Americans exposed to polychlorinated biphenyls (PCBs) from the consumption of fish from the St. Lawrence River. (nih.gov)
The present study addresses the question of whether PCB exposure has affected in vivo CYP1A2 activity among Mohawk men and women at Akwesasne. (nih.gov)
Role1
Essential role for induction of cytochrome P-448. (wakehealth.edu)
Drug1
Coadministration of lopinavir/ritonavir and phenytoin results in two-way drug interaction through cytochrome P-450 induction. (childrensmercy.org)