Oxidative stress in hemodialysis patients treated with a dialysis membrane which has alpha-tocopherol bonded to its surface

BACKGROUND: MDA, a major product of LPO, was shown to be increased in plasma of patients with end-stage renal failure (ESRF) undergoing hemodialysis (HD). Elevated oxidative stress in ESRF patients is a result of multiple pathogenetic factors. HD treatment has been shown to be one important cause of accelerated radical generation. The aim of our study was to examine whether treatment with a dialysis membrane which has alpha-tocopherol hydrophobically bonded to its surface (Excebrane by Terumo, Japan) can decrease oxidative stress due to HD. METHODS: 10 ESRF patients undergoing HD three times weekly were examined. First, analysis was done when patients were still dialysed with the membranes used before the study. Thereafter, samples were taken when patients were dialysed first time with the Excebrane membrane, and six weeks after Excebrane treatment. Samples were collected always before and after HD session. A method with HPLC-separation and flourimetric detection was used to measure plasma concentration of MDA. RESULTS: After HD with the regularly used membranes MDA was found significantly increased (before HD 1.92 1.81-2.02] microM (median and interquartile ranges) vs. after HD 2.26 2.02-2.60] microM, p < 0.05) suggesting that MDA was produced during HD. The first time Excebrane was used MDA was decreased significantly (before HD 2.04 1.95-2.88] microM vs. after HD 1.35 1.19-1.92] microM, p < 0.05). After six weeks of Excebrane treatment, plasma MDA did not change significantly during HD (before HD 2.01 1.69-2.62] microM vs. after HD 1.95 1.42-2.20] microM). CONCLUSION: Oxidative stress due to HD might be significantly decreased by the Excebrane membrane. However, after six weeks of treatment with Excebrane no effect was seen on the initial plasma concentration of MDA compared to the time before.