Linus Pauling Institute, Oregon State University, Corvallis, OR, 97331, USA; School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA.
Linus Pauling Institute, Oregon State University, Corvallis, OR, 97331, USA; School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, 97331, USA.
Free Radic Biol Med. 2014 Jan;66:13-9. doi: 10.1016/j.freeradbiomed.2013.07.039. Epub 2013 Aug 3.
α-Tocopherol is a lipid-soluble antioxidant that is specifically required for reproduction and embryogenesis. However, since its discovery, α-tocopherol's specific biologic functions, other than as an antioxidant, and the mechanism(s) mediating its requirement for embryogenesis remain unknown. As an antioxidant, α-tocopherol protects polyunsaturated fatty acids (PUFAs) from lipid peroxidation. α-Tocopherol is probably required during embryonic development to protect PUFAs that are crucial to development, specifically arachidonic (ARA) and docosahexaenoic (DHA) acids. Additionally, ARA and DHA are metabolized to bioactive lipid mediators via lipoxygenase enzymes, and α-tocopherol may directly protect, or it may mediate the production and/or actions of, these lipid mediators. In this review, we discuss how α-tocopherol (1) prevents the nonspecific, radical-mediated peroxidation of PUFAs, (2) functions within a greater antioxidant network to modulate the production and/or function of lipid mediators derived from 12- and 12/15-lipoxygenases, and (3) modulates 5-lipoxygenase activity. The application and implication of such interactions are discussed in the context of α-tocopherol requirements during embryogenesis.
α-生育酚是一种脂溶性抗氧化剂，专门用于繁殖和胚胎发生。然而，自从发现α-生育酚以来，其除了抗氧化剂之外的特定生物学功能，以及介导其胚胎发生所需的机制仍然未知。作为抗氧化剂，α-生育酚可保护多不饱和脂肪酸（PUFAs）免受脂质过氧化。α-生育酚在胚胎发育过程中可能需要保护对发育至关重要的多不饱和脂肪酸，特别是花生四烯酸（ARA）和二十二碳六烯酸（DHA）。此外，ARA 和 DHA 通过脂氧合酶酶代谢为生物活性脂质介质，并且α-生育酚可以直接保护这些脂质介质，或者可以介导它们的产生和/或作用。在这篇综述中，我们讨论了α-生育酚（1）如何防止多不饱和脂肪酸的非特异性、自由基介导的过氧化，（2）在更大的抗氧化网络中发挥作用以调节来自 12-和 12/15-脂氧合酶的脂质介质的产生和/或功能，以及（3）调节 5-脂氧合酶活性。讨论了这些相互作用在胚胎发生期间α-生育酚需求方面的应用和意义。
