Biomaterial Database

Effects of polychlorinated dibenzo-p-dioxin and dibenzofuran congeners in human lymphoblastoid cells on aryl hydrocarbon hydroxylase activity. 1995

C Kiyohara, and T Hirohata, and Y Masuda

Department of Public Health, Faculty of Medicine, Kyushu University, Fukuoka, Japan.

The separate and concurrent effects of polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners on aryl hydrocarbon hydroxylase (AHH) activity in human lymphoblastoid cells were examined. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD) induced AHH activity about 9-fold acetone-treated AHH activity, while octachlorodibenzo-p-dioxin (octaCDD) did not affect the AHH activity and 2,4,6,8-tetrachlorodibenzofuran (2,4,6,8-tetraCDF) reduced the AHH activity by 34%. The concurrent effect of 2,3,7,8-tetraCDD with 1,3,6,8-tetraCDD on AHH inducibility was much smaller than expected. The concurrent effect of 2,3,7,8-tetraCDD with 2,4,6,8-tetraCDF, octaCDD or 3,3',4,4',5,5'-hexaCB was as much as the effect of 2,3,7,8-tetraCDD alone. There was a difference between 3-methylcholanthrene (MC) and 2,3,7,8-tetraCDD in the concurrent effects of 3-methylsulfone-3',4,4',5-tetraCB (3-MSF-3',4,4',5-tetraCB) on AHH activity. The concurrent effect of MC with 3-MSF-3',4,4',5-tetraCB on AHH activity was equal to the effect of MC alone while that of 2,3,7,8-tetraCDD and 3-MSF-3',4,4',5-tetraCB on AHH activity was inhibitory. These results imply that congeners of PCDD and PCDF are considered to be more or less effective and isozymes of cytochrome P450, key enzymes for the AHH, induced by them are differently inhibited.

UI	MeSH Term	Description	Entries
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D011078	Polychlorinated Biphenyls	Industrial products consisting of a mixture of chlorinated biphenyl congeners and isomers. These compounds are highly lipophilic and tend to accumulate in fat stores of animals. Many of these compounds are considered toxic and potential environmental pollutants.	PCBs,Polychlorinated Biphenyl,Polychlorobiphenyl Compounds,Biphenyl, Polychlorinated,Biphenyls, Polychlorinated,Compounds, Polychlorobiphenyl
D002461	Cell Line, Transformed	Eukaryotic cell line obtained in a quiescent or stationary phase which undergoes conversion to a state of unregulated growth in culture, resembling an in vitro tumor. It occurs spontaneously or through interaction with viruses, oncogenes, radiation, or drugs/chemicals.	Transformed Cell Line,Cell Lines, Transformed,Transformed Cell Lines
D004785	Environmental Pollutants	Substances or energies, for example heat or light, which when introduced into the air, water, or land threaten life or health of individuals or ECOSYSTEMS.	Environmental Pollutant,Pollutant,Pollutants,Pollutants, Environmental,Pollutant, Environmental
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000072317	Polychlorinated Dibenzodioxins	Dibenzodioxin derivatives that contain multiple chloride atoms bound to the benzene ring structures.	TCDD,Tetrachlorodibenzodioxin,2,3,7,8-Tetrachlorodibenzo-p-dioxin,Chlorinated Dibenzo-p-dioxins,Dibenzo(b,e)(1,4)dioxin, 2,3,7,8-tetrachloro-,PCDD,Polychlorinated Dibenzo-p-dioxins,Polychlorinated Dibenzodioxin,Polychlorodibenzo-4-dioxin,Polychlorodibenzo-p-dioxin,Tetrachlorodibenzo-p-dioxin,Chlorinated Dibenzo p dioxins,Dibenzo-p-dioxins, Chlorinated,Dibenzo-p-dioxins, Polychlorinated,Dibenzodioxin, Polychlorinated,Dibenzodioxins, Polychlorinated,Polychlorinated Dibenzo p dioxins,Polychlorodibenzo 4 dioxin,Polychlorodibenzo p dioxin,Tetrachlorodibenzo p dioxin
D000072338	Dibenzofurans, Polychlorinated	Dibenzofurans that contain chloride atoms bound to the aromatic rings of the structure.	Chlorinated Dibenzofurans,Chlorodibenzofurans,Polychlorinated Dibenzofurans,Dibenzofurans, Chlorinated
D001189	Aryl Hydrocarbon Hydroxylases	A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.	Microsomal Monooxygenases,Xenobiotic Monooxygenases,Hydroxylases, Aryl Hydrocarbon,Monooxygenases, Microsomal,Monooxygenases, Xenobiotic