Keratinocyte superoxide generation.
We have demonstrated using the reduction of cytochrome c, that the keratinocyte cell line H357 generates superoxide at significant rates (8.36 nmol/h/10[6] cells). The rate of superoxide release decreased as the cells reached confluence. Superoxide production was increased more than twofold following preincubation with IL-1beta, or by the addition of the Ca2+ ionophore, Ionomycin. Other stimuli known to activate the NADPH oxidase of phagocytes were ineffective, but the regulatory cytokine IFNgamma lowered the rate of release. Inhibitors of lipoxygenase function decreased the rate of superoxide production, whereas inhibitors of cyclo-oxygenase, xanthine oxidase, or NADPH oxidase failed to inhibit. The addition of NADH or NADPH to whole cells increased the rate threefold.
Turner
C P
CP
Department of Biochemistry, University of Bristol, School of Medical Sciences, UK.
Toye
A M
AM
Jones
O T
OT
D003574:Cytochrome c Group / Q000378:metabolism; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D015759:Ionomycin / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism*; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D008856:Microscopy, Fluorescence; D009062:Mouth Neoplasms; D009243:NAD / Q000494:pharmacology; D009249:NADP / Q000494:pharmacology; D019255:NADPH Oxidases / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D002722:Chlorobenzenes
D003574:Cytochrome c Group; D007211:Indoles; D007371:Interferon-gamma; D007375:Interleukin-1; D015759:Ionomycin; D007476:Ionophores; D016859:Lipoxygenase Inhibitors; D009243:NAD; D009249:NADP; D019255:NADPH Oxidases; D013481:Superoxides; C060893:MK-886; D002722:Chlorobenzenes