Vitamin E supplementation increases LDL resistance to ex vivo oxidation in hemodialysis patients.

Background: Oxidative stress and alterations in lipid metabolism observed in hemodialysis patients potentiate the low-density lipoprotein (LDL) oxidability, recognized as a key event during early atherogenesis.

Objective: To explore the effects of an oral vitamin E supplementation on oxidative stress markers and LDL oxidability in hemodialysis patients.

Methods: Fourteen hemodialysis patients and six healthy volunteers were given oral vitamin E (500 mg/day) for six months. Oxidative stress was assessed using: plasma and lipoprotein vitamin E levels [high-performance liquid chromatography (HPLC) procedure]; thiobarbituric acid reactive substances (TBARS, Yaggi method); and copper-induced LDL oxidation. All parameters were evaluated before initiation of vitamin E supplementation, and at three and six months thereafter.

Results: At baseline, a significantly higher TBARS concentration and a higher LDL oxidability were observed in hemodialysis patients when compared to controls. After six months of vitamin E supplementation, TBARS and LDL oxidability were normalized in hemodialysis patients.

Conclusion: Our data confirm that hemodialysis patients are exposed to oxidative stress and increased susceptibility to ex vivo LDL oxidation. Since oral vitamin E supplementation prevents oxidative stress and significantly increases LDL resistance to ex vivo oxidation, supplementation by natural antioxidants such as vitamin E may be beneficial in hemodialysis patients.