Smith Kylie Sherée, Lee Chia-Lin, Ridlington James W, Leonard Scott W, Devaraj Sridevi, Traber Maret G
Department of Nutrition and Food Management, Oregon State University, Corvallis, Oregon 97331, USA.
Lipids. 2003 Aug;38(8):813-9. doi: 10.1007/s11745-003-1130-9.
Vitamin E supplementation could elevate circulating vitamin E metabolites while modulating oxidative and inflammatory status in end-stage renal failure patients undergoing hemodialysis. Plasma concentrations of carboxyethyl-hydroxychromanols (alpha- and gamma-CEHC), ascorbic acid, alpha- and gamma-tocopherols, F2-isoprostanes, and inflammatory biomarkers [tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), ferritin, and C-reactive protein (CRP)] were measured in blood samples obtained from patients (n = 11) before and after dialysis on two occasions prior to, and at 1 and 2 mon of daily vitamin E supplementation (400 IU RRR-alpha-tocopherol). Supplementation nearly doubled plasma alpha-tocopherol concentrations (from 18 +/- 0.5 to 31 +/- 1.7 microM, P < 0.0001), whereas gamma-tocopherol concentrations decreased (from 2.8 +/- 0.3 to 1.7 +/- 0.2 microM, P = 0.001). Serum alpha-CEHC increased 10-fold from 68 +/- 3 to 771 +/- 175 nM (P < 0.0001), and gamma-CEHC increased from 837 +/- 164 to 1136 +/- 230 nM (P = 0.008). Vitamin E supplementation also increased postdialysis hematocrits from 38 +/- 1% to 41 +/- 1% (P < 0.001). Dietary antioxidant intakes (vitamins E and C) were low in most subjects; plasma ascorbic acid levels (88 +/- 27 microM) decreased significantly with dialysis (33 +/- 11 microM, P = 0.01). Plasma IL-6, CRP, TNF-alpha, and free F2-isoprostane concentrations were elevated throughout the study. There is a complex relationship between chronic inflammation and oxidative stress that is not mitigated by short-term vitamin E supplementation. Importantly, serum vitamin E metabolite concentrations that increased 10-fold within 30 d of supplementation did not increase further, suggesting routes other than urine for removal of metabolites.
补充维生素E可提高终末期肾衰竭血液透析患者循环中维生素E代谢产物的水平，同时调节其氧化和炎症状态。在每日补充维生素E（400 IU RRR-α-生育酚）之前、补充1个月和2个月时，分别采集11例患者透析前后的血样，检测血浆中羧乙基-羟基色满醇（α-和γ-CEHC）、抗坏血酸、α-和γ-生育酚、F2-异前列腺素以及炎症生物标志物[肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）、铁蛋白和C反应蛋白（CRP）]的浓度。补充维生素E使血浆α-生育酚浓度几乎增加了一倍（从18±0.5微摩尔/升增至31±1.7微摩尔/升，P<0.0001），而γ-生育酚浓度降低（从2.8±0.3微摩尔/升降至1.7±0.2微摩尔/升，P = 0.001）。血清α-CEHC从68±3纳摩尔/升增至771±175纳摩尔/升，增加了10倍（P<0.0001），γ-CEHC从837±164纳摩尔/升增至1136±230纳摩尔/升（P = 0.008）。补充维生素E还使透析后血细胞比容从38±1%增至41±1%（P<0.001）。大多数受试者的膳食抗氧化剂摄入量（维生素E和C）较低；血浆抗坏血酸水平（88±27微摩尔/升）在透析后显著降低（33±11微摩尔/升，P = 0.01）。在整个研究过程中，血浆IL-6、CRP、TNF-α和游离F2-异前列腺素浓度均升高。慢性炎症与氧化应激之间存在复杂的关系，短期补充维生素E并不能缓解这种关系。重要的是，补充维生素E 30天内血清维生素E代谢产物浓度增加了10倍，但并未进一步升高，这表明除尿液外还有其他途径清除代谢产物。
