title: Chronic ingestion of cadmium and lead alters the bioavailability of essential and heavy metals, gene expression pathways and genotoxicity in mouse intestine.
abstract: Chronic ingestion of environmental heavy metals such as lead (Pb) and cadmium (Cd) causes various well-documented pathologies in specific target organs following their intestinal absorption and subsequent accumulation. However, little is known about the direct impact of the non-absorbed heavy metals on the small intestine and the colon homeostasis. The aim of our study was to compare the specific bioaccumulation and retention of Cd and Pb and their effect on the essential metal balance in primary organs, with those occurring specifically in the gastrointestinal tract of mice. Various doses of Cd (5, 20 and 100 mg l(-1)) and Pb (100 and 500 mg l(-1)) chloride salts were provided in drinking water for subchronic to chronic exposures (4, 8 and 12 weeks). In contrast to a clear dose- and time-dependent accumulation in target organs, results showed that intestines are poor accumulators for Cd and Pb. Notwithstanding, changes in gene expression of representative intestinal markers revealed that the transport-, oxidative- and inflammatory status of the gut epithelium of the duodenum, ileum and colon were specifically affected by both heavy metal species. Additionally, in vivo comet assay used to evaluate the impact of heavy metals on DNA damage showed clear genotoxic activities of Cd, on both the upper and distal parts of the gastrointestinal tract. Altogether, these results outline the resilience of the gut which balances the various effects of chronic Cd and Pb in the intestinal mucosa. Collectively, it provides useful information for the risk assessment of heavy metals in gut homeostasis and further disease's susceptibility.
authors.affiliation: Bactéries Lactiques & Immunité des Muqueuses, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, Inserm U 1019, CNRS UMR 8204, Université Lille Nord de France, 1 rue du Pr Calmette, BP 245, 59019, Lille, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Breton
authors.forename: Kelly
authors.initials: K
authors.lastname: Le Clère
authors.forename: Catherine
authors.initials: C
authors.lastname: Daniel
authors.forename: Mathieu
authors.initials: M
authors.lastname: Sauty
authors.forename: Lauren
authors.initials: L
authors.lastname: Nakab
authors.forename: Thierry
authors.initials: T
authors.lastname: Chassat
authors.forename: Joëlle
authors.initials: J
authors.lastname: Dewulf
authors.forename: Sylvie
authors.initials: S
authors.lastname: Penet
authors.forename: Christophe
authors.initials: C
authors.lastname: Carnoy
authors.forename: Patrick
authors.initials: P
authors.lastname: Thomas
authors.forename: Bruno
authors.initials: B
authors.lastname: Pot
authors.forename: Fabrice
authors.initials: F
authors.lastname: Nesslany
authors.forename: Benoît
authors.initials: B
authors.lastname: Foligné
mesh_terms: D000818:Animals; D001682:Biological Availability; D019256:Cadmium Chloride / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D004249:DNA Damage / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism; D007422:Intestines / Q000187:drug effects*; D007854:Lead / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D019216:Metals, Heavy / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D051379:Mice; D008807:Mice, Inbred BALB C; D009153:Mutagens / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D019216:Metals, Heavy; D009153:Mutagens; D007854:Lead; C029891:lead chloride; D019256:Cadmium Chloride