Cell membrane fatty acid composition in Type 1 (insulin-dependent) diabetic patients: Relationship with sodium transport abnormalities and metabolic control

We have studied the fatty acid composition of erythrocyte membrane phospholipids in nine Type 1 (insulin-dependent) diabetic patients and nine healthy control subjects. Cell membranes from the diabetic patients showed a marked decrease in the total amount of polyunsaturated fatty acids (19.0%±2.2 vs 24.6%±1.4, p<0.0001) mainly at the expense of docosahexaenoic acid C22∶6(n3) (2.9%±1.1 vs 5.3%±1.3, p<0.001), and arachidonic acid C20∶4 n6 (12.0%±1.6 vs 15.1%±0.6, p<0.0005). Conversely, the total amount of saturated fatty acids was significantly increased (p<0.05) and the polyunsaturated/saturated ratio was decreased in the Type 1 diabetic patients (p<0.00005). Neither the time from diagnosis, nor C-peptide levels, correlated with parameters indicating a poor metabolic control of Type 1 diabetes. However, C22∶6(n−3) and total n−3 content significantly correlated with HbA1c (r=−0.79 and r=−0.88, respectively, p<0.01), fructosamine (r=−0.71 and r=−0.74, respectively, p<0.05), and Na+-K+ ATPase activity (maximal rate/Km quotient) (r=0.78 and r=0.71, respectively, p