Biochemistry

Free phosphatidic acid is found in nature , although in small amounts compared to other glycerophosphalipids. Glycerophospholipids include cardiolipin, which is part of mitochondrial membranes. Sphingolipids (sphingomyelins) are composed of two molecules of fatty acids , one molecule of the amino alcohol sphingosine, nitrogenous base and phosphoric acid . These lipids are contained in the membrane of animal and plant cells, they are rich in nerve tissue, kidneys, and liver. Complex lipids also include glycolipids. They are built from sphingosine, a higher fatty acid and carbohydrate moiety (galactose, glucose, galactosamine or neuraminic acid). Glycolipids include cerebrosides, sulfatides, gangliosides, which play a role in the implementation of the functions of biological membranes. Complex lipids are found in the white matter of the brain, blood cells, etc. The composition of cerebrosides includes D -galactose , fatty acids, amino alcohol sphingosine. They are in the gray matter of the brain. Sulfatides are similar in structure to cerebrosides , but contain a residue of suljuric acid in the molecule . The ganglioside molecules include higher fatty acid, sphingosine, D-glucose, D-galactose, amino sugar derivatives. Steroids. This is a group of esters formed by the interaction of high molecular weight cyclic alcohols and higher fatty acids. The most important representative of steroids is cholesterol (cholesterol). In the body, it performs the following functions', it acts as a precursor to many biologically important compounds (steroid hormones, bile acids, vitamin D ), is part of cell membranes, increases the resistance of red blood cells to hemolysis, participates in nerve impulses, and is a kind of “ insulator ” for nerve cells. By their chemical nature, steroids are derivatives of cyclic alcohol - cyclopentaneperhydrophenanthrene. In the esterification of the hydroxyl group located at C 3 , cholesterol esters are formed. It is a key intermediate in the synthesis of other compounds. Cholesterol plays a role in the development of one of the most common "diseases of civilization" - atherosclerosis of blood vessels . In particular, it was found that when passbig through the vascular system of complexes of cholesterol with proteins (P-lipoproteins and pre-p-lipoproteins), it stands out, is deposited in the thickness of the vascular wall and forms atherosclerotic plaques . The latter reduce the elasticity of the walls and narrow the lumen of the vessels, which leads to a deterioration in the supply of tissues with oxygen and nutrients. 132