• Genomics & Informatics
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• v.2 no.2
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• pp.75-80
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• 2004

In a variety of animal species, the perinatal exposure of experimental animals to the 2,3,7,8-tetrachlorodibenzo­p-dioxin (TCDD) leads to the immune dysfunction, which is more severe and persistent than that caused by adult exposure. We report here the changes of gene expression and the identification of the marker-genes representing the dioxin exposure. The expressions of the transcripts were analyzed using the 11 K oligonucleotide­microarray from the bone marrow cells of male C57BL/6J mice after an intraperitoneal injection of $1{\mu}g$ TCDD/kg body weight at various time intervals: gestational 6.5 day(G6.5), 13.5 day(G13.5), 18.5 day(G18.5), and postnatal 3 (P3W)and 6 week (P6W). The type of self-organizing maps(SOM) representing the specific exposure dioxin could be identified as follows; G6.5D(C14), G13.5D(C0, C5, C10, C18), G18.5D(7): P3W(C2, C21), and P6W(C4, C15, C20). The candidate marker-genes were restricted to the transcripts, which could be consistently expressed greater than $\pm$2-fold in three experiments. The resulting candidates were 85 genes, the characteristics of that were involved in cell physiology and cell functions such as cell proliferation and immune function. We identified the biomarker-genes for dioxin exposure: smc -like 2 from SOM C14 for the dioxin exposure at G6.5D, focal adhesion kinase and 6 other genes from C0, and protein tyrosine phosphatase 4a2 and 3 other genes from C5 for G13.5D, platelet factor 4 from C7 for G18.5D, fos from C2 for P3W.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.782-787
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• 2002

This study was carried out to investigate the protective effect of chitosan on lipid peroxidation and key lipid parameters in Sprague-Dawley rat (SO rat) accutely exposured to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Male SO rats received single intraperitoneal (ip) injection of TCDD (40 j.lg/kg), and were given diet containing 3 or 5% chitosan for 4 weeks from 1 week before TCDD treatment. The gain in body weight was less in group treated with TCDD than in CON group, while that of Ch/H+ TCDD group (5% chitosan diet) increased. The decrease in liver and testis weight caused by TCDD was prevented by high dietary intake of chitosan (5% chitosan). Serum (total cholesterol, triglyceride, HDL-C, and LDL-C) and liver lipid parameters (total lipid, total cholesterol, and triglyceride) were significantly elevated in TCDD-induced rats, but these parameters excluding HDL-C were significantly reduced in high dietary intake of chitosan (5% chitosan). These findings suggest that chitosan is believed to be a possible protective effect against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in rat.

• Korean Journal of Pharmacognosy
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• v.32 no.2 s.125
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• pp.121-127
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• 2001

The effect of bear bile on 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD)-induced hepatotoxicity was investigated in 6-week-old C57BL/6 male mice. Bear bile (100 mg/kg or 500 mg/kg) was administered orally daily for 4 weeks, respectively. From the second week, $10\;{\mu}g/kg$ of TCDD was administered to the bear bile-treated animals orally once a week for 3 weeks (a total of $30\;{\mu}g/kg$). There were no specific clinical findings and significant body weight changes in all groups. Although the livers in TCDD-treated mice appeared a severe hypertrophy and many necrotic foci, and changed to yellow-brown color in gross findings, these lesions were remarkably reduced by bear bile administration. The elevated serum activities of alanine transaminase, aspartate transaminase, alkaline phosphatase, and lactate dehydrogenase due to TCDD were significantly decreased by bear bile treatment (P<0.05). The lipid peroxidation induced by TCDD was significantly prevented by bear bile administration (P<0.05). In histological examinations, there were a moderate necrosis of hepatic cells around central veins, severe cytoplasmic vacuolizations, inflammatory cell infiltrations, and remarkable fatty changes in the liver of TCDD-treated animals. However, the lesions were dose-dependently inhibited by the bear bile treatments. These findings indicate that bear bile may have a protective effect against TCDD-induced hepatotoxicity in mice.

• Biomedical Science Letters
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• v.18 no.1
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• pp.1-9
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• 2012

Differentially expressed genes by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were identified in order to evaluate them as dioxin-sensitive markers and crucial signaling molecules to understand dioxin-induced toxic mechanisms in human bronchial cells. Gene expression profiling was analyzed by cDNA microarray and ten genes were selected for further study. They were cytochrome P450, family 1, subfamily B, polypeptide 1 (CYP1B1), S100 calcium binding protein A8 (calgranulin A), S100 calcium binding protein A9 (calgranulin B), aldehyde dehydrogenase 1 family, member A3 (ALDH6) and peroxiredoxin 5 (PRDX5) in up-regulated group. Among them, CYP1B1 was used as a hallmark for dioxin and sharply increased by TCDD exposure. Down-regulated genes were IK cytokine, interferon-induced protein with tetratricopeptide repeats 1 (IFIT1), nuclease sensitive element binding protein 1 (NSEP1), protein tyrosine phosphatase type VI A, member 1 (PTP4A1), ras oncogene family 32 (RAB32). Although up-regulated 4 genes in microarray were coincided with northern hybridization, down-regulated 5 genes showed U-shaped expression pattern which is sharply decreased at lower doses and gradually increased at higher doses. These results introduce some of TCDD-responsive genes can be sensitive markers against TCDD exposure and used as signaling cues to understand toxicity initiated by TCDD inhalation in pulmonary tissues.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.78-86
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• 2005

Dioxins, especially 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD or dioxin), are ubiquitous environmental contaminants. TCDD is known that it has toxic effects in animals and humans, including chloracne, immune, reproductive and developmental toxicities, carcinogenicity, wasting syndrome and death. TCDD induces a broad spectrum of biological responses, including disruption of normal hormone signaling pathways, reproductive and developmental defects, immunotoxicity, liver damage, wasting syndrome and cancer. Many researches showed that TCDD induces gene expression of transcriptional factors related cell proliferation, signal transduction, immune system and cell cycle arrest at molecular and cellular levels. These toxic actions of TCDD are usually mediated with AhR (receptor, resulted from cell culture, animal and clinical studies). cDNA microarray can be used as a highly sensitive and informative marker for toxicity. Additionally, microarray analysis of dioxin-toxicity is able to provide an opportunity for the development of candidate bridging biomarkers of dioxin-toxicity. Through microarray technology, it is possible to understand the therapeutic effects of agonists within the context of toxic effects, classify new chemicals as to their complete effects on biological systems, and identify environmental factors that may influence safety.

• Environmental Mutagens and Carcinogens
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• v.25 no.1
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• pp.40-46
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• 2005

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) displays high toxicity in animals and has been implicated in human carcinogenesis. Although the mechanism of carcinogenesis by TCDD is unclear, it is considered to be a non-genotoxic compound and tumor promoter. In our experiment, we investigated the effects of TCDD on gene expression in mouse skin carcinogenesis. We used cDNA microarray to detect the differential gene expression in tumors induced in hairless mouse skin by MNNG plus TCDD protocol. We found that erb-2, c-ets2 and p27$^{kip1}$ were significantly up-regulated, but TNFR2, AKT-l, integrin $\beta$l, maspin, IGF-l, c-raf-l, Rb were significantly down-regulated, in tumor region, respectively. We also found that the expression of 53 genes involved in cen cycle, signal transduction, apoptosis, adhesion molecule, angiogenesis, and invasion, were changed two fold more, in tumor surrounding region. These data suggest that TCDD alters the expression of a large array of genes involved in apoptosis, cytokine production and angiogenesis in mouse skin carcinogenesis.

• Toxicological Research
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• v.15 no.1
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• pp.89-93
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• 1999

2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) is known to induce cytochrome p450 1A1 and to activate c-Src kinase and p21 Ras. This study examined the molecular interactions of adaptor proteins including Shc, Grb2, and Sos in rat primary hepatocytes and their relationship to the induction of CYP1A1 by TCDD. TCDD induced CYP1A1 level and EROD activity in a dose-dependent mode. Sos/Grb2 association isincreased by TCDDㅑㅜ a dose dependent mode. Tyrosine phosphorylated Shc, mainly p152, onloads to Grb2/Sos complex upon TCDD stimulation. The electrophoretic mobility shift of Sos is showed by TCDD. These results indicate that TCDD modulated the molecular interaction features of adaptor compoes proteins including Shc, Grb2, and Cnl in early signaling pathway of TCDD-mediated CYP 1A1 induction of rat primary hepatocyte.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.75.3-76
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• 2003

The present study was performed to examine mitogen-activated protein kinase associated pathways in mediation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced cell apoptosis in cultured Jurkat T cells. TCDD significantly decreased cell viability in a concentration-dependent manner (p<0.05 at 10-300 nM). TCDD (10 nM) also time-dependently decreased cell viability (p<0.05 at 12-48 h). c-Jun NH$_2$-terminal kinase was significantly phosphorylated with TCDD treatment in a time dependent manner. (omitted)

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.127-127
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• 2001

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.129-129
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• 2002

2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) a prototype of many halogenated aromatic hydrocarbons, is a ubiquitous, persistent environmental contaminant and the most powerful carcinogen categorized by IARC. Despite extensive research, the mechanisms of TCDD-induced carcinogenesis are poorly understood.(omitted)