Department of Animal and Dairy Science, University of Georgia, Athens, GA.
Equine Studies Group, WALTHAM Center for Pet Nutrition, Slough, Berkshire.
J Equine Vet Sci. 2020 Aug;91:103103. doi: 10.1016/j.jevs.2020.103103. Epub 2020 Apr 29.
Vitamin E is an essential antioxidant that may benefit athletes by reducing oxidative stress and influencing cytokine expression. Supplements can be derived from natural or manufactured synthetic sources. This study aimed to determine (1) if supplemental vitamin E is beneficial to exercising horses and (2) if there is a benefit of natural versus synthetic vitamin E. After 2 weeks on the control diet (vitamin E-deficient grain and hay), 18 horses were divided into three groups and fed the control diet plus (1) 1000 IU/d synthetic α-tocopherol (SYN-L), (2) 4000 IU/d synthetic α-tocopherol (SYN-H), or (3) 4000 IU/d RRR-α-tocopherol (natural source [NAT]). On day 7, horses began a 6-week training protocol, with standard exercise tests (SETs) performed before and after the 6-week protocol. Venous blood samples were collected on days 0, 7, 29, and 49. Horses fed NAT had higher α-tocopherol (P < .05) at post-SET1 through post-SET2. Plasma thiobarbituric acid-reactive substance levels were lower in NAT versus SYN-L horses after SET2 (P = .02). Serum aspartate aminotransferase was lower after exercise in NAT horses versus SYN-L and SYN-H (P = .02), and less reduction in stride duration was seen after exercise in NAT as compared with SYN-L and SYN-H (P = .02). Gene expression of tumor necrosis factor α was lower in NAT compared with SYN-H (P = .01) but not SYN-L. In conclusion, feeding higher levels of natural vitamin E source resulted in higher serum α-tocopherol levels as well as some improvement in oxidative and inflammatory response and improved functional outcomes in response to an exercise test.
维生素 E 是一种必需的抗氧化剂，通过减少氧化应激和影响细胞因子表达，可能使运动员受益。补充剂可以从天然来源或人工合成来源获得。本研究旨在确定：（1）补充维生素 E 是否对运动马有益，（2）天然维生素 E 与合成维生素 E 是否有区别。在接受缺乏维生素 E 的谷物和干草的对照饮食 2 周后，18 匹马被分为 3 组，分别喂食对照饮食加（1）1000 IU/d 合成α-生育酚（SYN-L），（2）4000 IU/d 合成α-生育酚（SYN-H），或（3）4000 IU/d RRR-α-生育酚（天然来源[NAT]）。在第 7 天，马匹开始进行为期 6 周的训练方案，在 6 周方案前后进行标准运动测试（SET）。在第 0、7、29 和 49 天采集静脉血样。喂食 NAT 的马匹在 SET1 后到 SET2 后α-生育酚水平更高（P<.05）。与 SYN-L 组相比，在 SET2 后 NAT 组的血浆硫代巴比妥酸反应物水平较低（P=.02）。与 SYN-L 和 SYN-H 相比，NAT 组的血清天门冬氨酸氨基转移酶在运动后较低（P=.02），并且在运动后 NAT 组的步幅持续时间减少较少（P=.02）。与 SYN-H 相比，NAT 组的肿瘤坏死因子-α的基因表达较低（P=.01），但与 SYN-L 相比则无差异。总之，较高水平的天然维生素 E 来源可导致更高的血清α-生育酚水平，以及在氧化应激和炎症反应方面有一些改善，并且在运动测试后改善了功能结果。
