لخّصلي

Reactive oxygen species (ROS) can be formed accidentally and on purpose (specially).An accidental method of formation of reactive oxygen species is their formation as by-products of the reaction as a result of the work of enzymes: monoamine oxidases, oxidases of D- and L-amino acids, polyamine oxidases, lysyl oxidases.However, when the ratio of ROS and antioxidants is violated, ROS accumulates, which can lead to the development of diseases: hypertension, atherosclerosis, coronary heart disease, bronchopulmonary diseases, malignant cell growth, rheumatoid arthritis, gastritis, neurodegenerative processes (Parkinsonism, Alzheimer's disease).The factors contributing to the formation of ROS and the occurrence of lipid peroxidation are called prooxidants, these include: pharmacological agents, poisons, toxins, allergens, ionizing, ultraviolet radiation and other types of radiation.Reactive oxygen species are formed as a result of the work of enzymes: NADPH oxidases, myeloperoxidases, NO synthases, lipoxygenases, cyclooxygenases.Spontaneously ROS are formed, for example, in the respiratory chain of mitochondria, during microsomal oxidation, and hemoglobin oxidation in erythrocytes.Participation in the synthesis of biologically active substances (thyroid hormones, eicosanoids); 4.Specially.This leads to cell death.

Reactive oxygen species (ROS) can be formed accidentally and on purpose (specially).
The accidental formation of ROS can
occur spontaneously (without the
participation of enzymes) and under the
action of enzymes (in this case, ROS are
formed as a by-product of the reaction).
Spontaneously ROS are formed, for
example, in the respiratory chain of
mitochondria, during microsomal oxidation, and hemoglobin oxidation in erythrocytes. With proper
functioning of antioxidant protection systems, the spontaneously formed ROS are quickly inactivated and do
not have a significant effect on the body. However, when the ratio of ROS and antioxidants is violated, ROS
accumulates, which can lead to the development of diseases: hypertension, atherosclerosis, coronary heart
disease, bronchopulmonary diseases, malignant cell growth, rheumatoid arthritis, gastritis,
neurodegenerative processes (Parkinsonism, Alzheimer's disease). The factors contributing to the formation
of ROS and the occurrence of lipid peroxidation are called prooxidants, these include: pharmacological
agents, poisons, toxins, allergens, ionizing, ultraviolet radiation and other types of radiation.
An accidental method of formation of reactive oxygen species is their formation as by-products of the
reaction as a result of the work of enzymes: monoamine oxidases, oxidases of D- and L-amino acids,
polyamine oxidases, lysyl oxidases.
Specially. Reactive oxygen species are formed as a result of the work of enzymes: NADPH oxidases,
myeloperoxidases, NO synthases, lipoxygenases, cyclooxygenases. At the same time, ROS performs a
number of important functions in the body:

1. Protective role (macrophages kill microorganisms by oxidative explosion induced by NADPH-oxidase);


2. Renewal of membrane lipids (old lipids are oxidized by ROS and new ones are built in their place);


3. Participation in the synthesis of biologically active substances (thyroid hormones, eicosanoids);


4. Regulation of vascular tone (ROS participate in the regulation of vascular tone by inhibiting endogenous
   nitric oxide);


5. Cell proliferation (ROS stimulate the proliferation of fibroblasts of immunocompetent cells);


6. Regulation of metabolic processes as intracellular messengers (ROS can act independently and together
   with other intracellular messengers);


7. Induction of immune reactions (ROS stimulate the proliferation of immunocompetent cells).
   Under the action of reactive oxygen species, membrane lipids, cellular proteins and nucleic acids are
   destroyed. This leads to cell death.
   To protect the cell from ROS, there are anti-oxidant (АО) systems: