REVIEW: Hydroperoxide-Reducing Enzymes in the Regulation of Free-Radical Processes

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Mars G. Sharapov^1,a*, Sergey V. Gudkov^2,3,4, and Vadim Z. Lankin⁵

¹Institute of Cell Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia

²Prokhorov Institute of General Physics, Russian Academy of Sciences, 119991 Moscow, Russia

³Lobachevsky State University of Nizhny Novgorod, 603022 Nizhny Novgorod, Russia

⁴All-Russian Research Institute of Phytopathology, 143050 Bolshiye Vyazemy, Russia

⁵National Medical Research Center of Cardiology, Ministry of Health of the Russian Federation, 121552 Moscow, Russia

^* To whom correspondence should be addressed.

Received May 18, 2021; Revised July 6, 2021; Accepted July 6, 2021

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The review presents current concepts of the molecular mechanisms of oxidative stress development and describes main stages of the free-radical reactions in oxidative stress. Endogenous and exogenous factors of the oxidative stress development, including dysfunction of cell oxidoreductase systems, as well as the effects of various external physicochemical factors, are discussed. The review also describes the main components of the antioxidant defense system and stages of its evolution, with a special focus on peroxiredoxins, glutathione peroxidases, and glutathione S-transferases, which share some phylogenetic, structural, and catalytic properties. The substrate specificity, as well as the similarities and differences in the catalytic mechanisms of these enzymes, are discussed in detail. The role of peroxiredoxins, glutathione peroxidases, and glutathione S-transferases in the regulation of hydroperoxide-mediated intracellular and intercellular signaling and interactions of these enzymes with receptors and non-receptor proteins are described. An important contribution of hydroperoxide-reducing enzymes to the antioxidant protection and regulation of such cell processes as growth, differentiation, and apoptosis is demonstrated.

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KEY WORDS: oxidative stress, reactive oxygen species, free radicals, peroxiredoxins, glutathione peroxidases, glutathione S-transferases

DOI: 10.1134/S0006297921100084

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