Stress is the response of the organism to various external and internal events. All response reactions change from metabolic processes to metabolic stresses in minutes or even seconds. The scientists most often discuss oxidative, nitrosative and carbonyl stresses which are characterized by the accumulation of free radicals and other reactive oxygen species, as well as active carbonyl compounds, in the cells and extracellular fluid. These active (signal) molecules are powerful nonspecific modifiers of the structure and function of proteins, lipids, carbohydrates, and they interfere with bioenergetics. Small doses of active signal molecules are necessary for adaptive reactions of the body, they inhibit metabolic disorders, especially protein ...