Potential role of tryptophan derivatives in stress responses characterized by the generation of reactive oxygen and nitrogen species.
To face physicochemical and biological stresses, living organisms evolved endogenous chemical responses based on gas exchange with the atmosphere and on formation of nitric oxide (NO(*)) and oxygen derivatives. The combination of these species generates a complex network of variable extension in space and time, characterized by the nature and level of the reactive oxygen (ROS) and nitrogen species (RNS) and of their organic and inorganic scavengers. Among the latter, this review focusses on natural 3-substituted indolic structures. Tryptophan-derived indoles are unsensitive to NO(*), oxygen and superoxide anion (O(2)(*-)), but react directly with other ROS/RNS giving various derivatives, most of which have been characterized. Though the detection of some products like kynurenine and nitroderivatives can be performed in vitro and in vivo, it is more difficult for others, e.g., 1-nitroso-indolic compounds. In vitro chemical studies only reveal the strong likelihood of their in vivo generation and biological effects can be a sign of their transient formation. Knowing that 1-nitrosoindoles are NO donors and nitrosating agents indicating they can thus act both as mutagens and protectors, the necessity for a thorough evaluation of indole-containing drugs in accordance with the level of the oxidative stress in a given pathology is highlighted.
Peyrot
Fabienne
F
Institut de Chimie des Substances Naturelles, CNRS, Gif sur Yvette, France. fabienne.peyrot@univ-paris5.fr
Ducrocq
Claire
C
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002273:Carcinogens; D006801:Humans; D007735:Kynuramine / Q000378:metabolism; D007737:Kynurenine / Q000378:metabolism; D008550:Melatonin / Q000378:metabolism*; D009153:Mutagens; D020030:Nitric Oxide Donors / Q000378:metabolism; D009585:Nitrogen Dioxide / Q000378:metabolism; D009603:Nitroso Compounds / Q000378:metabolism / Q000633:toxicity; D010084:Oxidation-Reduction; D030421:Peroxynitrous Acid / Q000378:metabolism; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D013312:Stress, Physiological; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000378:metabolism
D000975:Antioxidants; D002273:Carcinogens; D009153:Mutagens; D020030:Nitric Oxide Donors; D009603:Nitroso Compounds; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; D030421:Peroxynitrous Acid; D012701:Serotonin; D007737:Kynurenine; D007735:Kynuramine; D014364:Tryptophan; D008550:Melatonin; D009585:Nitrogen Dioxide