Effect of α-lipoic acid on platelet reactivity in type 1 diabetic patients

OBJECTIVE: Type 1 diabetes is associated with increased platelet reactivity. We investigated whether α-lipoic acid (ALA) has any effect on platelet reactivity in these patients. RESEARCH DESIGN AND METHODS: We randomly assigned 51 type 1 diabetic patients to ALA (600 mg once daily) or placebo for 5 weeks. Platelet reactivity was evaluated by the PFA-100 method and by measuring CD41 and CD62 platelet expression. C-reactive protein (CRP) and 8-iso-prostaglandin F2α serum levels also were measured. RESULTS: Baseline variables were similar in the two groups. After treatment, closure time was longer (P = 0.006) and CD62P platelet expression was lower, both before (P = 0.002) and after (P = 0.009) ADP stimulation in the ALA group compared with the placebo group. CRP and 8-iso-prostaglandin F2α levels showed no differences between the two groups. CONCLUSIONS: Our data show that ALA reduces measures of platelet reactivity ex vivo in type 1 diabetic patients, independently of antioxidant or anti-inflammatory effects.