Polycyclic aromatic hydrocarbons (PAHs) and dioxins are lipophilic organic pollutants occurring widely in the terrestrial environment. In order to study the PAHs and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) transfer in the food chain, pigs have been fed with milk mixed either with 14C-phenanthrene, with 14C-benzo[a]pyrene or with 14C-TCDD. The analysis of portal and arterial blood radioactivi...

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces abnormalities in steroid-dependent processes such as mammary cell proliferation, gonadotropin release and maintenance of pregnancy. In the current study, the effects of TCDD on the pharmacokinetics of 17beta-estradiol and progesterone were examined. Adult Sprague-Dawley rats were ovariectomized and pretreated with TCDD (15 microg/kg p.o.) or ve...

A variety of health effects have been attributed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), but little information is available on the course of a verified high-level TCDD intoxication. In this paper we describe two cases of heavy intoxication with TCDD and present a 2-year follow-up including clinical, biochemical, hematologic, endocrine, and immunologic parameters monitored in two women, ...

Acute exposure to hepatotoxic doses of 2,3,7,8-tetrachloro- dibenzo-p-dioxin (TCDD) in mice is characterized by differential gene expression that can be phenotypically anchored to elevated levels of serum alanine aminotransferase, increased relative liver weights, hepatic steatosis, inflammation, and hepatocellular necrosis. Unlike most studies that focus on acute exposure effects, this study e...

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been identified as a toxic contaminant of chlorophenols and related hydrocarbons that are widely used in agriculture and industry. It has been implicated in various diseases, including human cases of chloracne (1) and porphyria cutanea tarda (2) and in chick edema (3). Its teratogenicity has been documented in rats (4) and mice (5). Monkeys fed tox...

We systematically evaluated studies published through May 2014 in which investigators assessed the doseresponse relationship between serum levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the occurrence of diabetes mellitus (DM), and we investigated the extent and sources of interstudy heterogeneity. The doseresponse relationship between serum TCDD and DM across studies was examined usi...

We have studied the effect of several environmental chemicals on the transient expression of a chloramphenicol acetyltransferase (cat) reporter gene linked to the promoter sequences in the long terminal repeat (LTR) of the human immunodeficiency virus type 1 (HIV-1). Aflatoxin B1, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; dioxin) and benzo[a]pyrene cause a significant increases in CAT expressi...

TCDD (2,3,7,8-tetrachlorodibenzo- p -dixoin) induces phase II drug-metabolizing enzyme NQO1 [NAD(P)H:quinone oxidoreductase; EC 1.6.99.2; DT-diaphorase] in a wide range of mammalian tissues and cells. Here, we analysed the molecular pathway mediating NQO1 induction by TCDD in mouse hepatoma cells. Inhibition of protein synthesis with CHX (cycloheximide) completely blocks induction of NQO1 by TC...

Conventional biochemical and molecular techniques identified previously several genes whose expression is regulated by the aryl hydrocarbon receptor (AHR). We sought to map the complete spectrum of AHR-dependent genes in male adult liver using expression arrays to contrast mRNA profiles in Ahr-null mice (Ahr(-/-)) with those in mice with wild-type AHR (Ahr(+)(/)(+)). Transcript profiles were de...

Cycloheximide superinduces the transcription of CYP1A1 in the presence of an agonist for the Ah receptor (AhR). To investigate the molecular target for "superinduction," we analyzed the agonist-induced degradation of AhR. Whereas 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD), a potent agonist of AhR, induces a rapid reduction of the AhR protein, cycloheximide blocks the down-regulation of steady ...