Background: Recently, numerous anomalies of erythrocyte rheology and function have been reported in diabetic patients. These changes are thought to be related to the alteration of erythrocyte membrane fluidity and may play an important role in diabetic retinopathy (DR). Nonetheless, the principal factors contributing to fluidity change remain undetermined. The influence of erythrocyte membrane fatty acid components on membrane fluidity and retinopathy was evaluated in patients with type 2 diabetes.
Methods: The fatty acid components and fluidity of erythrocyte membranes in 63 patients with type 2 diabetes with and without retinopathy were examined using high-performance liquid chromatography and fluorescence polarization.
Results: The content and composition of erythrocyte membrane arachidonate (C20:4n-6) was significantly lower in diabetics than in controls, and diabetics had significantly increased erythrocyte membrane microviscosity compared with controls. Furthermore, membrane microviscosity was higher in diabetics with DR than those without DR. In the diabetic patients, arachidonic acid contents of erythrocyte membranes were significantly, inversely correlated with erythrocyte membrane microviscosity, fasting blood glucose, glycosylated hemoglobin, triglycerides and cholesterol, and positively correlated with the insulin sensitivity index.
Conclusions: The results suggest that erythrocyte membrane fatty acid components may contribute to alterations in membrane fluidity in patients with type 2 diabetes. Alterations in membrane fluidity may play an important role in the development of diabetic microangiopathy.