BACKGROUND
Recently, increased oxidative stress has been proposed as a major cause of vascular complications of patients with diabetes mellitus. Increased generation of oxygen free radicals in patients with diabetes mellitus could deplete cellular antioxidants and inactivate endothelial dependent vasodilating factor (EDRF), such as nitric oxide (NO). The purpose of this study was to evaluate whether the antioxidant alpha-lipoic acid (ALA) is effective in endothelial dysfunction of brachial artery, which induced by increased oxidative stress in postmenopausal diabetic women using high resolution ultrasound technique and initial reaction time (IRT) measurement. METHODS: We enrolled 11 menopausal women (mean age, 56.5+/-5.1 years) with uncomplicated type 2 diabetes. All patients were taking 1200 mg of ALA (Thioctacid(R), Bukwang, Korea). We measured of superoxide anion (O2-) in neutrophils as a marker of oxidative stress. Flow-mediated dilation (FMD) was measured using a high-resolution ultrasound. RESULTS: After treatment of ALA, fasting blood glucose was decreased significantly, the endothelium-dependent vasodilation of the brachial artery was increased, and O2- production was also decreased significantly. CONCLUSION: These results show that short term ALA treatment could improve the endothelial dysfunction in patients with type 2 diabetes mellitus. This improvement might be related with the antioxidants effect of ALA.