The pathobiochemistry of nitrogen dioxide.
Nitrogen dioxide (*NO2) is an oxidizing free radical which can initiate a variety of destructive pathways in living systems, and several diseases are suspected to be connected with both exogenously and endogenously formed *NO2. Peroxynitrite (ONOO-/ONOOH) is believed to be an important endogenous source of *NO2 radicals, but other sources, among them enzymatically ones, have been identified recently. It also became clear during the last few years that in vivo formation of 3-nitrotyrosine strictly depends on the availability of *NO2 radicals. Since nitrogen dioxide is a very toxic compound an arsenal of antioxidants (e.g. vitamin C, glutathione, vitamin E, and beta-carotene) must eliminate this harmful radical in vivo. Here the recently identified superoxide (O2*-)-dependent formation of peroxynitrate (O2NOO-) and the central role of vitamin C are of special importance.
Kirsch
Michael
M
Institut für Physiologische Chemie, Universitäts-klinikum, Essen, Germany.
Korth
Hans-Gert
HG
Sustmann
Reiner
R
de Groot
Herbert
H
D000818:Animals; D006801:Humans; D009585:Nitrogen Dioxide / Q000737:chemistry / Q000633:toxicity*; D010083:Oxidants, Photochemical / Q000737:chemistry / Q000633:toxicity; D030421:Peroxynitrous Acid / Q000494:pharmacology
D010083:Oxidants, Photochemical; D030421:Peroxynitrous Acid; D009585:Nitrogen Dioxide