The Antioxidant Power of Arginine/Nitric Oxide Attenuates Damage Induced by Methyl Viologen Herbicides in Plant Cells

Abstract

Since time ago, studying the redox homeostasis in cells is one of the most intriguing and complex puzzle that researchers are confronting to solve. In plant cells, several biochemical and molecular mechanisms have evolved for keeping the pro-oxidant/antioxidant environment between acceptable physiological ranges. Here, we present novel evidence supporting the amino acid L-arginine as a bioactive molecule with antioxidant capacity when plant cells are challenged by an acute oxidative stress triggered by the herbicide methyl viologen (MV). Our results are feeding the controversy generated about the presence of a nitric oxide synthase (NOS) gene in plants, since they indicate that the tandem formed by the NOS substrate L-arginine and the product of the NOS activity, nitric oxide (NO), are potent cellular resources for maintaining cell integrity and coping against high concentrations of reactive oxygen species.