Abstract: Objective  To investigate the influence of lipoic acid on the serum 8isoprostaglandin F2α (8isoPGF2α) level in type 2 diabetic patients with  lower venous extremity. Methods  This study  recruited  `288 patients with type 2 diabetes， including 191 patients with only type 2 diabetes (T2DM group) and 97 type 2 diabetic patients with peripheral artery disease (LVED group) in accordance with anklebrachial index (ABI). The LVED group was divided into two groups: conventional therapy group  received conventional therapy and the other lipoic acid group was given lipoic acid 0.6  g a day for two weeks on the  basis of conventional therapy. An age and sexmatched group of 100 healthy subjects were also recruited. The serum 8isoPGF2α level was measured. The painless walking distance and the maximum walking distance before and after treatment were recorded. Results  The serum 8isoPGF2α level in T2DM group was significantly higher than that in control group (P＜0.05). The serum 8isoPGF2α level in LVED group was significantly higher than that in T2DM group (P＜0.05). The serum 8isoPGF2α level was positively correlated with the severity of  LVED. After two  weeks  treatment， the serum 8isoPGF2α level in conventional therapy group and lipoic acid group both decreased， and that in lipoic acid group was significantly lower (P＜0.05). In addition， the painless walking distance and the maximum walking distance in conventional therapy group and lipoic acid group significantly increased (P＜0.05)， and those in lipoic acid group were significantly longer (P＜0.05). Conclusion  The serum 8isoPGF2α level is correlated with the severity of  LVED. Lipoic acid could decrease the serum 8isoPGF2α level and improve the clinical symptoms in type 2 diabetic patients with LVED.

Key words: diabetes mellitus, type 2； diabetic angiopathies；isoprostanes；thioctic acid