Among the structurally diverse collection of lipids that comprise the membrane lipidome, polyunsaturated phospholipids are particularly vulnerable to oxidation. The role of α-tocopherol (vitamin E) is to protect this influential class of membrane phospholipid from oxidative damage. Whether lipid-lipid interactions play a role in supporting this function is an unanswered question. Here, we compare the molecular organization of polyunsaturated 1-[²H₃₁]palmitoyl-2-docosahexaenoylphosphatidylethanolamine (PDPE-d₃₁) and, as a control, monounsaturated 1-[²H₃₁]palmitoyl-2-oleoylphosphatidylethanolamine (POPE-d₃₁) mixed with sphingomyelin (SM) and α-tocopherol (α-toc) (2:2:1 mol) by solid-state ²H NMR spectroscopy. In both cases the effect of α-toc appears similar. Spectral moments reveal that the main chain melting transition of POPE-d₃₁ and PDPE-d₃₁ is broadened beyond detection. A spectral component attributed to the formation of inverted hexagonal H_II phase in coexistence with lamellar L_α phase by POPE-d₃₁ (20 %) and PDPE-d₃₁ (18 %) is resolved following the addition of α-toc. Order parameters in the remaining L_α phase are increased slightly more for POPE-d₃₁ (7%) than PDPE-d₃₁ (4%). Preferential interaction with polyunsaturated phospholipid is not apparent in these results. The propensity for α-toc to form phase structure with negative curvature that is more tightly packed at the membrane surface, nevertheless, may restrict the contact of free radicals with lipid chains on phosphatidylethanolamine molecules that accumulate polyunsaturated fatty acids.

在构成膜脂质体的脂质结构多样的集合中，多不饱和磷脂特别容易被氧化。α-生育酚（维生素E）的作用是保护这种有影响力的膜磷脂免受氧化损伤。脂质-脂质相互作用是否在支持该功能中起作用尚未解决。在这里，我们比较了多不饱和的1- [ ² H ₃₁ ]棕榈酰基-2-二十二碳六烯基磷脂酰乙醇胺（PDPE-d ₃₁）的分子结构，并作为对照，比较了单不饱和的1- [ ² H ₃₁ ]棕榈酰基-2-油酰基磷脂酰乙醇胺（POPE-d ₃₁）通过固态² H NMR光谱与鞘磷脂（SM）和α-生育酚（α-toc）（2：2：1 mol）混合。在这两种情况下，α-toc的作用都相似。谱矩表明POPE-d的主链的熔化转变₃₁和PDPE-d ₃₁被加宽超越检测。归因于反相六角形H的形成的光谱成分_II相共存与层状大号_α由POPE-d相₃₁（20％）和PDPE-d ₃₁（18％）被加入α-TOC的以下解决。在除此之外的L阶参数_α相是为POPE-d稍微增加₃₁（7％）比PDPE-d ₃₁（4％）。在这些结果中，与多不饱和磷脂的优先相互作用并不明显。但是，α-toc形成具有负曲率的相结构的倾向更紧密地堆积在膜表面上，这可能会限制自由基与磷脂酰乙醇胺分子上积累多不饱和脂肪酸的脂质链的接触。