Does Diabetes Mellitus Affect Cell Membrane Dynamics?

Summary: In this study we report the use of l-anilino-8-naphthalenesulphonate äs a fluorescence probe to investigate the properties of plasma membranes derived from normal and diabetic red blood cells. The binding of l-anilino-8-naphthalenesulphonate to diabetes-affected erythrocyte membranes, äs compared with controls, was measured by means of fluorescence polarization and fluorescence titration techniques. These measurements demonstrated anomalous l-anilino-^S-naphthalenesulphonate binding to pathological red cell membranes. The amount of l-anilino-8-naphthalenesulphonate bound to diabetic erythrocyte membranes was greater than that of controls. This fluorometric study indicated that the outer monolayer binding of l-anilino-8-naphthalenesulphonate was markedly augmented in the erythrocyte membranes of diabetic pa-tients. Significant correlations were found between l-anilino-8-naphthalenesulphonate binding parameters and membrane lipid composition. The correlation between these binding parameters and non-enzymatic protein glycation was poor or moderate. Though the fluorescence intensity and emission maximum were quite similar in both groups investigated, binding studies reveäled that there were approximately 1.2 times the number of l-anilino-8-naphthalenesul-phonate binding sites and a 33 % increase in the KO value in diabetic membranes, suggesting significant differences in the environment of the l-anilino-8-naphthalenesulphonate binding sites in these two groups o