[Free radical oxidation of lipids and thiol groups in the formation of a cataract].

Content of primary (diene conjugates), secondary (ketodienes), end (Schiff's bases) products of free radical oxidation (FRO) of lipids was determined, as well as content of total and non-protein-bound thiols in human lens at different stages of cataractogenesis. Lens opacity was estimated by quantitative morphometric analysis. Participation of FRO of lipids in lens opacity is proved. It is shown that total thiols of lens fibres are rapidly inactivated when the intensity of lipid FRO is increased at the expense of the fall of glutathione level. These processes promote the formation of high molecular protein aggregates in the lens and cataract development. Coefficients of linear correlation between the indicated parameters are presented. A conclusion is drawn concerning possible prevention of cataract development by decreasing the level of accumulation of lipid peroxides and by maintaining high concentration of reduced glutathione in the lens.