Caco-2 cell metabolism of oxygen-derived radicals.
Reactive oxygen metabolites have been associated with gastrointestinal injury and may play a role as mediators of inflammation. The effect of oxygen metabolites on Caco-2 cell viability (trypan blue exclusion and 51Cr release), hexose monophosphate shunt activity, and glutathione was assessed. Caco-2 cells were incubated with amino acid oxidase, xanthine oxidase, menadione, and t-butylhydroperoxide in the presence and absence of superoxide dismutase, catalase, mannitol, and butylated hydroxytoluene. With amino acid oxidase, trypan blue exclusion decreased (P < 0.01) and 51Cr release, oxidized glutathione, and shunt activity increased (P < 0.05). The addition of catalase attenuated these changes. Trypan blue exclusion decreased (P < 0.005) and 51Cr release, oxidized glutathione, and shunt activity increased (P < 0.01) with xanthine oxidase. The addition of superoxide dismutase caused a further increase in 51Cr release, oxidized glutathione, and shunt activity (P < 0.01), which was prevented by the addition of catalase or mannitol. t-Butylhydroperoxide did not effect 51Cr release or trypan blue exclusion, but oxidized glutathione and shunt activity increased (P < 0.01). The increase in shunt activity was prevented by preincubation with butylated hydroxytoluene (P < 0.01). Menadione did not alter trypan blue exclusion or 51Cr release, but caused an increase in oxidized glutathione and shunt activity (P < 0.001). The increase in shunt activity was attenuated by preincubation with butylated hydroxytoluene (P < 0.001). Menadione also caused a depletion of total glutathione.(ABSTRACT TRUNCATED AT 250 WORDS)
Baker
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Department of Pediatrics, University of Massachusetts Medical School, Worcester 01655.
Baker
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D002860:Chromium Radioisotopes / Q000378:metabolism; D003110:Colonic Neoplasms; D004064:Digestive System / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D016877:Oxidants / Q000494:pharmacology; D010427:Pentose Phosphate Pathway / Q000187:drug effects / Q000502:physiology; D010545:Peroxides / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014343:Trypan Blue; D014407:Tumor Cells, Cultured; D014812:Vitamin K / Q000494:pharmacology; D020122:tert-Butylhydroperoxide
D002860:Chromium Radioisotopes; D016877:Oxidants; D010545:Peroxides; D017382:Reactive Oxygen Species; D014812:Vitamin K; D020122:tert-Butylhydroperoxide; D005978:Glutathione; D014343:Trypan Blue