Berdnikovs Sergejs, Abdala-Valencia Hiam, McCary Christine, Somand Michelle, Cole Rokeisha, Garcia Alex, Bryce Paul, Cook-Mills Joan M
Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
J Immunol. 2009 Apr 1;182(7):4395-405. doi: 10.4049/jimmunol.0803659.
Reports indicate contradictory outcomes for anti-inflammatory functions of the alpha-tocopherol isoform of vitamin E in clinical studies of asthma and atherosclerosis. These seemingly disparate clinical results are consistent with novel unrecognized properties of isoforms of vitamin E reported in this study. We demonstrate that the isoform d-gamma-tocopherol elevates inflammation in experimental asthma. Moreover, d-gamma-tocopherol, at as little as 10% the concentration of d-alpha-tocopherol, ablates the anti-inflammatory benefit of the d-alpha-tocopherol isoform. A mechanism for these opposing immunoregulatory functions of purified tocopherols at physiological concentrations is not through modulation of expression of several cytokines, chemokines, or adhesion molecules, but is, at least in part, by regulation of endothelial cell signals during leukocyte recruitment. These opposing regulatory functions of vitamin E isoforms have impact on interpretations of vitamin E studies. In summary, our studies with purified tocopherol isoforms alter our understanding of vitamin E regulation of vascular function and asthma.
报告显示,在哮喘和动脉粥样硬化的临床研究中,维生素E的α-生育酚异构体的抗炎功能结果相互矛盾。这些看似不同的临床结果与本研究中报道的维生素E异构体的新的未被认识的特性是一致的。我们证明,异构体d-γ-生育酚会加剧实验性哮喘中的炎症。此外,d-γ-生育酚的浓度仅为d-α-生育酚的10%时,就会消除d-α-生育酚异构体的抗炎益处。生理浓度下纯化生育酚的这些相反免疫调节功能的机制不是通过调节几种细胞因子、趋化因子或黏附分子的表达,而是至少部分地通过在白细胞募集中调节内皮细胞信号来实现的。维生素E异构体的这些相反调节功能对维生素E研究的解释产生影响。总之,我们对纯化生育酚异构体的研究改变了我们对维生素E调节血管功能和哮喘的理解。