title: Sialic acid attenuates the cytotoxicity of the lipid hydroperoxides HpODE and HpETE.
abstract: Reduction of peroxide molecular species is an essential function in living organisms. In previous studies, we proposed a new function for the sialic acid N-acetylneuraminic acid (Neu5Ac)--that of antioxidant/hydrogen peroxide scavenging agent. On the basis of the reaction scheme, Neu5Ac is thought to act as a general antioxidant of all hydroperoxide-type species (R-OOHs). The concentration of tert-butyl hydroperoxide (t-BuOOH) decreased after co-incubation with N-acetylneuraminic acid. Neu5Ac also decreased the R-OOH concentration in solutions of peroxylinolenic acid (13(S)-hydroperoxy-(9Z,11E)-octadecadienoic acid, HpODE) and peroxyarachidonic acid (15(S)-hydroperoxy-(5Z,8Z,11Z,13E)-eicosatetraenoic acid, HpETE)--two lipid hydroperoxides that participate in many physiological events. Moreover, the cytotoxicity of both these lipid hydroperoxides was attenuated by reaction with Neu5Ac acid. Our results suggest that N-acetylneuraminic acid is a potential antioxidant of most hydroperoxides that accumulate in organisms.
authors.affiliation: School of Pharmaceutical Sciences, Teikyo University, Sagamiko, Sagamihara, Kanagawa 229-0195, Japan. ryo-iiji@pharm.teikyo-u.ac.jp
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Iijima
authors.forename: Takatsugu
authors.initials: T
authors.lastname: Ichikawa
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Yamazaki