HOMOCYSTEINE IS A FACTOR IN THE DEVELOPMENT OF DEMENTIA
Homocysteine (Hcis) is a sulfur-containing non-protein amino acid. Hcis is a member of the group of endogenous thiols that provide the redox balance of cells. Endogenous thiols can exhibit both pro-and antioxidant properties, depending on their physiological state. Hcis, formed in the methylation reaction of methionine, has neurotoxic properties. Normally, the level of homocysteine in the blood should not exceed 7 mmol/l. It was noted that when the level of Hcis is more than 11.9 mmol/l, the risk of damage to the white matter of the brain is tripled, and an increase in the level of Hcis more than 14 mmol / l doubles the risk of developing Alzheimer's disease. The causes of hyperhomocysteinemia are defects in the structure of genes encoding the necessary enzymes for the neutralization of homocysteine, smoking, taking certain medications, thyroid diseases and metabolic disorders, as well as, most often present in elderly patients, a deficiency of B vitamins (folic acid, B12, B6). The hippocampus is particularly sensitive to the effects of homocysteine. Molecular damage to the nerve cells of the brain structure responsible for the processes of memory formation is accompanied by various cognitive disorders that are prone to progression. The neurotoxicity of homocysteine is due to several mechanisms: on the one hand, the formation of endothelial dysfunction, leading to hypoperfusion of neurons, on the other hand, a direct effect on the nerve cell in the form of oxidative stress, which results in cellular apoptosis.