Biochemistry

processes of synthesis of fatty acids and triacylglycerols intensify, which leads to their accumulation and deposition in the cells. Hepatosteatosis is characterized by the accumulation of an excess amount of triacylglycerols in its cells, which leads to degenerative changes in the cells and impairment of their functions. Fat metabolism is actively taking place in the liver, including two interrelated processes - the synthesis of triacylglycerols and the synthesis of phospholipids. Strengthening the synthesis of triacylglycerols inhibits the formation of phospholipids, and vice versa. At the same time, triacylglycerols are easily deposited in liver cells, and phospholipids are transported to tissues, where they participate in various processes. With a lack of lipotropic substances necessary for the synthesis of phospholipids, it is inhibited, and fatty acids go to the synthesis of triacylglycerols, which accumulate in liver cells, causing its dystrophy. Nutrient materials are involved in the normalization of lipid metabolism disorders. The sources of dynamic metal groups necessary for the synthesis of lipotropic substances are methionine, vitamins U, B I5 , choline, lecithin, betaine. The methylation of many compounds is affected by folacin and vitamin B I2 . The oxidation of lipids, including cholesterol, to the final products involves niacin, tryptophan, from which niacin is partially formed in the presence of vitamin В 6 , В ]2, vitamins С, P, lipoicacid, lecithin, choline. The settling of cholesterol from body fluids (causing the development of atherosclerosis, the formation of gallstones) is prevented by polyunsaturated fatty acids that are contained in vegetable oils. Also their role in lowering the formation of low-density lipoproteins (containing cholesterol) and enhancing the destruction of these particles in the blood is important. Vitamin C prevents a decrease in the number of high-density lipoproteins, in which cholesterol is metabolized faster than in low-density particles. The absorption of this lipid from the intestine into the blood is inhibited by fl-sitosterol contained in vegetable fats. Excretion of cholesterol from the body through the colon stimulates В vitamins (especially thiamin), inositol, PUFA, as well as magnesium, ballast substances, sorbitol, xylitol. Some seafood has antisclerotic effects due to their content of PUFAs and iodine. 10.5 RANCIDITY OF FATS Biochemical (enzymatic) rancidity of fats occurs under the influence of mold enzymes: the lipase released by them causes the hydrolysis of fat. The resulting fatty acids undergo p-oxidation and subsequent decarboxylation. 207