Use of erythrocyte adhesion assay to predict the risk of diabetic complications

Simple diagnostic tools for the monitoring of an oxidative state are important in the self-monitoring of diabetic complications and other obesity-related disorders closely linked to oxidative stress. Cellular membranes are protected from oxidative damage by antioxidative enzymes and vitamins. A decrease in the level of these protective systems results in oxidative cellular damage by reactive oxygen species (ROS). In the evaluation of oxidative cellular damage that leads to numerous diseases, it is not only necessary to determine the amount of antioxidants or ROS, but also the accumulative cellular damages. In the present study, we developed a method for evaluation of the oxidative state of erythrocytes using less than 5 μl of whole blood. The method is based on two observations: (i) a decrease of the surface electrical charge in oxidized erythrocytes and (ii) a change in the oxidized erythrocytes’ adhesion to the positively charged surfaces. The proportion of human erythrocytes, which adhered to the high density amine-coated slides with the surface zeta potential of 18.4 mV reflected the cell oxidative state caused by t-butylhydroperoxide in vitro. In addition, the method was used to monitor the peripheral blood of diabetic Akita mice, whose risk of diabetic complications was interminably increased. The erythrocytes’ adhesion of diabetic Akita mice significantly decreased compared with that of control mice. The results of the adhesion assay correlated with the results of serological assays.