title: Heme oxygenase 1 overexpression increases iron fluxes in caco-2 cells.
abstract: Heme oxygenase-1 is a microsomal enzyme that, when induced by stress, protects the cells from oxidative injury. Heme oxygenase-1 participates in the cleavage of the heme ring producing biliverdin, CO and ferrous Fe. The released Fe becomes part of intracellular Fe pool and can be stored in ferritin or released by an iron exporter. The mechanism by which heme enters cells is not completely understood, although it had been suggested that it might be internalized by an endocytosis process. In this study, we expressed a full-length Heme oxygenase-1 cDNA in Caco-2 cells and measured intracellular iron content, heme-iron uptake and transport and immunolocalization of heme oxygenase-1 in these cells. We found that heme oxygenasc-1 expressing cells showed increased apical heme iron uptake and transepithelial transport when compared to control cells. These results suggested that heme oxygenase-1 mediates heme iron influx and efflux in intestinal cells.
authors.affiliation: Micronutrient Laboratory, Nutrition and Food Technology Institute, Universidad de Chile, Santiago, Chile.
authors.forename: María José
authors.initials: MJ
authors.lastname: Mendiburo
authors.forename: Sebastián
authors.initials: S
authors.lastname: Flores
authors.forename: Fernando
authors.initials: F
authors.lastname: Pizarro
authors.forename: Miguel
authors.initials: M
authors.lastname: Arredondo
mesh_terms: D018938:Caco-2 Cells / Q000378:metabolism; D004847:Epithelial Cells / Q000737:chemistry*; D005455:Fluorescent Antibody Technique; D015971:Gene Expression Regulation, Enzymologic; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000032:analysis* / Q000378:metabolism; D018613:Microscopy, Confocal; D013054:Spectrophotometry, Atomic; D013997:Time Factors
chemical_list: D007501:Iron; D051547:Heme Oxygenase-1