title: Chemical form of selenium affects its uptake, transport, and glutathione peroxidase activity in the human intestinal Caco-2 cell model.
abstract: Determining the effect of selenium (Se) chemical form on uptake, transport, and glutathione peroxidase activity in human intestinal cells is critical to assess Se bioavailability at nutritional doses. In this study, we found that two sources of L-selenomethionine (SeMet) and Se-enriched yeast each increased intracellular Se content more effectively than selenite or methylselenocysteine (SeMSC) in the human intestinal Caco-2 cell model. Interestingly, SeMSC, SeMet, and digested Se-enriched yeast were transported at comparable efficacy from the apical to basolateral sides, each being about 3-fold that of selenite. In addition, these forms of Se, whether before or after traversing from apical side to basolateral side, did not change the potential to support glutathione peroxidase (GPx) activity. Although selenoprotein P has been postulated to be a key Se transport protein, its intracellular expression did not differ when selenite, SeMSC, SeMet, or digested Se-enriched yeast was added to serum-contained media. Taken together, our data show, for the first time, that the chemical form of Se at nutritional doses can affect the absorptive (apical to basolateral side) efficacy and retention of Se by intestinal cells; but that, these effects are not directly correlated to the potential to support GPx activity.
authors.affiliation: US Department of Agriculture, Agricultural Research Service, Grand Forks Human Nutrition Research Center, P.O. Box 9034, Grand Forks, ND 58203, USA. huawei.zeng@ars.usda.gov
authors.forename: Huawei
authors.initials: H
authors.lastname: Zeng
authors.forename: Matthew I
authors.initials: MI
authors.lastname: Jackson
authors.forename: Wen-Hsing
authors.initials: WH
authors.lastname: Cheng
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Combs
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives / Q000494:pharmacology; D018938:Caco-2 Cells; D003545:Cysteine / Q000031:analogs & derivatives / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D016566:Organoselenium Compounds / Q000494:pharmacology; D012643:Selenium / Q000737:chemistry / Q000494:pharmacology*; D017279:Selenocysteine / Q000031:analogs & derivatives; D018038:Sodium Selenite / Q000494:pharmacology
chemical_list: D016566:Organoselenium Compounds; D017279:Selenocysteine; C062653:selenolanthionine; D005979:Glutathione Peroxidase; D012643:Selenium; D018038:Sodium Selenite; D003545:Cysteine; D000409:Alanine; C002979:selenomethylselenocysteine