Search results for "CYP2E1"

Interest of genotyping and phenotyping of drug-metabolizing enzymes for the interpretation of biological monitoring of exposure to styrene

2002

In the field of occupational and/or environmental toxicology, the measurement of specific metabolites in urine may serve to assess exposure to the parent compounds (biological monitoring of exposure). Styrene is one of the chemicals for which biological monitoring programs have been validated and implemented in environmental and occupational medicine. However, inter-individual differences in the urinary excretion exist both for the main end-products (mandelic acid and phenylglyoxylic acid) and for its specific mercapturic acids (phenylhydroxyethylmercapturic acids, PHEMA). This limits to a certain extent the use of these metabolites for an accurate assessment of styrene exposure. In a group…

Ethanol-Induced Oxidative Stress Modifies Inflammation and Angiogenesis Biomarkers in Retinal Pigment Epithelial Cells (ARPE-19): Role of CYP2E1 and …

2020

The retinal pigment epithelium (RPE) plays a key role in retinal health, being essential for the protection against reactive oxygen species (ROS). Nevertheless, excessive oxidative stress can induce RPE dysfunction, promoting visual loss. Our aim is to clarify the possible implication of CYP2E1 in ethanol (EtOH)-induced oxidative stress in RPE alterations. Despite the increase in the levels of ROS, measured by fluorescence probes, the RPE cells exposed to the lowest EtOH concentrations were able to maintain cell survival, measured by the Cell Proliferation Kit II (XTT). However, EtOH-induced oxidative stress modified inflammation and angiogenesis biomarkers, analyzed by proteome array, ELIS…

503 ALLELIC VARIANTS OF CYP2E1 GENE IN HEPATOCARCINOMA PATIENTS AND IN HEPATIC TUMOR CELL LINES

2011

Role and importance of polymorphisms with respect to DNA methylation for the expression of CYP2E1 enzyme

2014

Different individuals possess slightly different genetic information and show genetically-determined differences in several enzyme activities due to genetic variability. Following an integrated approach, we studied the polymorphisms and methylation of sites contained in the 5' flanking region of the metabolizing enzyme CYP2E1 in correlation to its expression in both tumor and non-neoplastic liver cell lines, since to date little is known about the influence of these (epi)genetic elements in basal conditions and under induction by the specific inductor and a demethylating agent. In treated cells, reduced DNA methylation, assessed both at genomic and gene level, was not consistently associate…

Effects of garlic powders with varying alliin contents on hepatic drug metabolizing enzymes in rats

2003

International audience; The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic…

Evaluation of Cytochrome P450 Activities in Human Hepatocytes In Vitro

2011

Major hepatic cytochrome P450 activities (CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4) can be simultaneously examined in human hepatocytes by incubation with a cocktail of multiple specific probes. Cocktail strategy in combination with mass spectrometry is shown to be a robust, fast, and sensitive procedure for P450 activity assessment. This procedure allows a drastic reduction of the number of cells required in the assay and sample analysis time and increases throughput and reproducibility. Major applications of the probe cocktail strategy are P450 phenotyping of hepatocytes and induction studies.

Autonomous molecularly crowded confinement in inkjet printed femtoliter-scale aqueous compartments

2019

Natural evolution has chosen the localization of biomolecular processes into crowded sub-cellular femtoliter (fL) scale compartments for organizing complex biological processes. [1] Many synthetic biology platforms with life-like activities have been able to mimic these systems under different compartment sizes regimes. [2] However, the fabrication of crowded compartments down to sub-cellular scales is challenging, mainly because of high surface-volume ratio of these systems, finally compromising the stability of the encapsulated biomolecules. In this regard, we here bridge this gap by showing the possibility to produce femtoliter-scale aqueous droplets using a novel inkjet printing approac…

Mitochondrial oxidative stress and CD95 ligand: A dual mechanism for hepatocyte apoptosis in chronic alcoholism

2002

Apoptosis plays an important role in the progression of alcohol-induced liver disease to cirrhosis. Oxidative stress is an early event in the development of apoptosis. The major aim of this study was to study the conditions in which oxidative stress occurs in chronic alcoholism and its relationship with apoptosis of hepatocytes. We have found that oxidative stress is associated with chronic ethanol consumption in humans and in rats, in the former independently of the existence of alcohol-induced liver disease. Ethanol or acetaldehyde induces apoptosis in hepatocytes isolated from alcoholic rats, but not in those from control rats. Inhibition of aldehyde dehydrogenase, but not of cytochrome …

Metabolism and bioactivation of toxicants in the lung. The in vitro cellular approach.

2005

Lung is a target organ for the toxicity of inhalated compounds. The respiratory tract is frequently exposed to elevated concentrations of these compounds and become the primary target site for toxicity. Occupational, accidental or prolonged exposure to a great variety of chemicals may result in acute or delayed injury to cells of the respiratory tract. Nevertheless, lung has a significant capability of biotransforming such compounds with the aim of reducing its potential toxicity. In some instances, the biotransformation of a given compound can result in the generation of more reactive, and frequently more toxic, metabolites. Indeed, lung tissue is known to activate pro-carcinogens (i.e. po…

Liver subcellular fractions from rats treated by organosulfur compounds from Allium modulate mutagen activation

2000

The effects of in vivo administration of naturally occurring organosulfur compounds (OSCs) from Allium species were studied on the activation of several mutagens. Male SPF Wistar rats were given p.o. one of either diallyl sulfide (DAS), diallyl disulfide (DADS), dipropyl sulfide (DPS) or dipropyl disulfide (DPDS) during 4 consecutive days and the ability of hepatic S9 and microsomes from treated rats to activate benzo[a]pyrene (BaP), cyclophosphamide (CP), dimethylnitrosamine (DMN), N-nitrosopiperidine (N-PiP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was determined in the Ames test. Administration of DAS, DPS and DPDS resulted in a significant increase of the activation of…