Altered membrane fatty acid composition and increased thromboxane A2 generation in platelets from patients with diabetes

Lipid composition of platelet membranes and thromboxane A₂ (TxA₂) generation by platelets were investigated in 42 diabetic patients (14 with macroangiopathic complications, 10 with microangiopathy and 18 without vascular complications) and in 42 clinically healthy subjects of similar age. All subjects were on a similar dietary regimen and the adherence to diet was checked by analysis of red blood cell lipids. Platelets from all groups of diabetic patients produced increased amounts of TxA₂ than platelets from controls (at least p <0.01) and patients with macroangiopathy produced more TxA₂ than patients without vascular complications and patients with microangiopathy (p <0.01) Platelet cholesterol and total platelet phospholipids were higher in patients with macroangiopathy, while the relative percentage of the different phospholipid fractions in platelet membrane and their saturated and unsaturated fatty acids were similar in the different groups. Arachidonic acid (AA) content in phosphatidylcholine (PC) was found to be significantly higher in diabetic patients than in controls (at least p <0.005). Moreover patients with macroangiopathy had higher AA (p <0.001) and lower eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) levels in PC (p <0.001) than the other groups of patients and controls.