Title

Hydroquinone modulates reactivity of peroxynitrite and nitric oxide production.

Authors

Kim, Ae Ra; Cho, Jae Youl; Lee, Ji Yeon; Choi, Jae Sue; Chung, Hae Young

Abstract

Peroxynitrite (ONOO−), a potent cytotoxic oxidant formed by the reaction of nitric oxide (*NO) and superoxide radical (*O2−), may be rapidly lethal in a cellular milieu due to oxidization and nitration processes. In the present study, hydroquinone displayed strong ONOO− scavenging activity and inhibitory effect on NO production in murine macrophage RAW264.7 cells. Hydroquinone strongly scavenged ONOO− induced dihydrorhodamine 123 oxidation in a dose-dependent manner compared with other reactive species such as *O2− and *NO. Hydroquinone also decreased levels of ONOO− induced nitrotyrosine of glutathione reductase and consequently prevented the enzyme from ONOO− induced damage. Furthermore, hydroquinone suppressed NO production, a cellular pathway for ONOO− formation, in lipopolysaccharide-activated RAW264.7 cells via inhibition of inducible NO synthase expression. The inhibitory effect by hydroquinone seems to be mediated by interruption of lipopolysaccharide-induced signalling such as activation of nuclear factor- kB and extracellular signal-related kinases 1 and 2. The results suggest that hydroquinone may potently modulate reactivity of ONOO− and may therefore be a useful agent against ONOO− mediated diseases.

Publication

Journal of Pharmacy & Pharmacology, 2005, Vol 57, Issue 4, p475

ISSN

0022-3573

Publication type

Academic Journal

DOI

10.1211/0022357055731