title: Effects of a vitamin E-modified dialysis membrane and vitamin C infusion on oxidative stress in hemodialysis patients.
abstract: Hemodialysis deteriorates oxidative stress. Vitamin E is an antioxidant whose regeneration is provided for by vitamin C. The authors tested the effects of a vitamin E-modified membrane (E), nonmodified cellulose membrane (O), and vitamin C infusion (500 mg, C) into the arterial blood line during dialysis on parameters of oxidative stress. In a short-term study, 24 patients were subjected to a single dialysis session with E, O, E with C, and O with C protocols. In a long-term study (12 weeks), 20 patients were randomized into groups with C and without C on each dialysis, and both groups had dialysis using O, E, and again O membrane for 4 weeks each. In the short-term study, thiobarbituric acid reacting substances (TBARS) in plasma rose after dialysis (p < 0.02) with O, and no changes were observed in the other 3 protocols. In the long-term study, predialysis TBARS declined when using E both in the groups with C (p < 0.02) and without C (p < 0.05). A switch over to O resulted in TBARS returning to baseline levels. The E membrane prevented an increase in lipid peroxidation during single dialysis, and long-term use of the E membrane also resulted in a decrease in the predialysis lipid peroxidation level. The antioxidant capacity of the E membrane was not enhanced by vitamin C infusion. High doses of vitamin C administered during dialysis using a nonmodified cellulose membrane prevented an increase in lipid peroxidation, most probably due to the enhanced rate of endogenous vitamin E regeneration.
authors.affiliation: Department of Internal Medicine I and Institute of Clinical Biochemistry and Laboratory Diagnostics, Charles University School of Medicine, Pilsen, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Eiselt
authors.forename: J
authors.initials: J
authors.lastname: Racek
authors.forename: L
authors.initials: L
authors.lastname: Trefil
authors.forename: K
authors.initials: K
authors.lastname: Opatrný
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D002482:Cellulose; D005260:Female; D005609:Free Radicals; D006801:Humans; D007262:Infusions, Intravenous; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D006435:Renal Dialysis / Q000009:adverse effects* / Q000295:instrumentation; D018709:Statistics, Nonparametric; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D008567:Membranes, Artificial; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D002482:Cellulose; D001205:Ascorbic Acid