Hypoosmotic hemolysis of erythrocytes by active carbonyl forms

Resumo

Low-molecular-weight dicarbonyls formed during free radical peroxidation of polyene lipids (malondialdehyde) and autooxidation (glyoxal) or other oxidative transformations of glucose (methylglyoxal) are able to modify the structure of lipid-protein supramolecular complexes of cells. We investigated changes in the erythrocyte membrane structure after an 18-h exposure of human red blood cells in the presence of various natural dicarbonyls. The changes in the mechanical properties of the membrane after membrane modification by carbonyls were evaluated by the susceptibility of erythrocytes to hypoosmotic hemolysis. It has been shown that treatment of red blood cells with malondialdehyde increases the resistance of these cells to hypoosmotic hemolysis, whereas the malondialdehyde isomer, methylglyoxal, in contrast, makes red blood cells more sensitive to the action of hypoosmotic solutions. Paradoxically, a homologue of malondialdehyde, glyoxal, has no effect on hemolysis of red blood cells in hypoosmotic solutions. The findings point to the possibility of the multidirectional effect of low-molecular-weight dicarbonyls with similar structures on the structure and function of biological membranes.