Relationship between Glutathione S-Transferase P1 Polymorphism and Bronchial Asthma and Atopic Dermatitis

We determined the prevalence of GSTP1-Ile105 and GSTP1-Val105 alleles in patients with bronchial asthma and atopic dermatitis and healthy children of 2 groups (randomized and nonatopic control). The GSTP1-Ile105/Val105 genotype determines the resistance to atopic dermatitis (odds ratio=0.51; 95% confidence interval: 0.28-0.92; p=0.023). However, both homozygotes are at high risk of developing atopic dermatitis (near-significant differences).     

Dose-Dependent Effect of α-Tocopherol on Activity of Xenobiotic Metabolizing Enzymes in Rat Liver

Oral treatment with -tocopherol for 4 days dose-dependently increased the content of cytochrome P450 (CYP), catalytic activities of CYP1A1, CYP1A2, CYP2B1, CYP2C, and activity of NADPH-cytochrome-P450 reductase in the liver of male rats, but did not change activity of glutathione S-transferase. These results suggest that -tocopherol induced the enzymes of phase I of xenobiotic metabolism, including CYP1 and CYP2 families involved in the metabolism of drugs and procarcinogenes.     

CAR expression and inducibility of CYP2B genes in liver of rats treated with PB-like inducers

The expression of the CAR gene and inducibility of CYP2B protein in the liver of male Wistar rats treated with phenobarbital (PB) and triphenyldioxane (TPD) were investigated. To clarify the role of phosphorylation/dephosphorylation in these processes, rats were treated with inhibitors of Ca(2+)/calmodulin-dependent kinase II (W7) or protein phosphatases PP1 and PP2A (OA) before induction. Constitutive expression of the CAR gene in livers of untreated rats was detected by multiplex RT-PCR. Treatment with W7 resulted in a 2.8-fold induction of CAR gene expression, whereas OA led to a 2.4-fold decrease of the mRNA level. The same results were obtained for CYP2B genes expression, which were increased by W7 treatment (two-fold) and decreased by OA (2.3-fold). PB-induction did not lead to significant alteration in the level of CAR gene expression, although CYP2B genes expression was enhanced two-fold over control values. TPD caused a two-fold increase of both CAR and CYP2B mRNA levels. Both inducers reduced the effects of inhibitors on CAR gene expression. Results of EMSA showed that PB, TPD or W7 alone induced formation of complexes of NR1 with nuclear proteins. Appearance of the complexes correlated with an increase in CYP2B expression, and their intensities were modulated by the protein kinase inhibitors. Thus, our results demonstrate that constitutive expressions of CAR as well as CYP2B during induction are regulated by phosphorylation/dephosphorylation processes.     

Mechanism of action of hepain on lymphocytes in vitro

In experiments on CBA mice in which a 2% suspension of red blood cells was used as the antigen, heparin was shown to prevent the migration of antibodies from antibody-producing cells substantially in vitro. On the addition of substances with the properties of detergents (Triton X-100, deoxycholate) in vitro to a suspension of plaque-forming spleen cells treated with heparin, the ability of the cells to form plaques was partially restored. It is concluded that heparin is able to interact with the outer membrane of immunocompetent cells and to inhibit migration of antibodies synthesized by them into the surrounding medium.Laboratory of Clinical Immunopathology, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 11, pp. 588–590, November, 1977.     

Quercetin Attenuates Benzo(α)pyrene-induced CYP1A Expression

<正>We studied effects of nutrient quercetin on cytochromes’Р450 1А(CYP1A)activities(measured spectrofluorimetrically using 7-ethoxy-resorufin for CYP1A1 and 7-methoxy-resorufin for CYP1A2 as substrates),on mR NA levels(measured by RT-PCR),and on DNA-binding activities(evaluated by an electrophoretic mobility shift assay)of proteins regulating CYP1A expression in untreated and benzo(α)pyrene(Ba P)-treated rats.Wistar rats     

Effect of triphenyldioxane on phase I xenobiotic metabolism enzymes in the liver of rats and rabbits

We studied the effect of triphenyldioxane on phase I xenobiotic metabolism enzymes in the liver of rats and rabbits. Total cytochrome P450 content, protein concentration, and catalytic activity of CYP2B, CYP3A, and CYP2C isoforms were measured. Triphenyldioxane significantly increases specific activity of CYP2B and CYP2C in the liver of rats and rabbits, respectively. Immunoblotting analysis of microsomal enzymes in the liver of animals showed that the increase in specific activity of CYP is related to high content of apoenzymes. We showed for the first time that rats and rabbits are characterized by interspecies differences in the induction of cytochrome P450 isoforms under the influence of triphenyldioxane. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 141, No. 6, pp. 646–648, June, 2006