title: Various Molecular Species of Diacylglycerol Hydroperoxide Activate Human Neutrophils via PKC Activation.
abstract: We have proposed that diacylglycerol hydroperoxide-induced unregulated signal transduction causes oxidative stress-related diseases. In this study, we investigated which molecular species of diacylglycerol hydroperoxide activated human peripheral neutrophils. All diacylglycerol hydroperoxides, diacylglycerol hydroxides, and diacyglycerols tested in the present study induced superoxide production by neutrophils. The ability to activate neutrophils among molecular species containing the same fatty acid composition was as follows; diacylglycerol hydroperoxide>diacylglycerol hydroxide>/=diacylglycerol. The diacylglycerol hydroperoxide composed of linoleate was a stronger activator for neutrophils than that composed of arachidonate. 1-Palmitoyl-2-linoleoylglycerol hydroperoxide (PLG-OOH) was the strongest stimulator for neutrophils. We reconfirmed that PLG-OOH activated protein kinase C (PKC) in neutrophils. PLG-OOH induced the phosphorylation of p47(phox), a substrate of PKC and a cytosolic component of NADPH oxidase, in neutrophils, as did N-formyl-methionyl-leucyl-phenylalanine or 4beta-phorbol-12beta-myristate-13alpha-acetate. Moreover, the time course of p47(phox) phosphorylation was comparable to that of superoxide production. These results suggest that PLG-OOH activated intracellular protein kinase C. PLG-OOH, produced via an uncontrolled process, can act as a biological second messenger to cause inflammatory disease from oxidative stress.
authors.affiliation: Department of Environmental and Preventive Medicine, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-8640, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kambayashi
authors.forename: Susumu
authors.initials: S
authors.lastname: Takekoshi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tanino
authors.forename: Keiichi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Minoru
authors.initials: M
authors.lastname: Nakano
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Hitomi
authors.forename: Tomoko
authors.initials: T
authors.lastname: Takigawa
authors.forename: Keiki
authors.initials: K
authors.lastname: Ogino
authors.forename: Yorihiro
authors.initials: Y
authors.lastname: Yamamoto