抗氧化劑增補對激烈運動及魚油引發之氧化壓力的影響

Abstract

運動與魚油對生理具有相當的影響，特別是降低TG及LDL-血脂質的部份，於學界及臨床上已具共識，但魚油富含多元不飽和脂肪酸的特性及高強度運動容易造成細胞蒙受氧自由基攻擊，可能導致氧化壓力昇高；抗氧化劑對消除有害自由基有明顯效果。本研究主要目的1)探討服用魚油與單次激烈運動形成之氧化壓力的差異，且兩者是否具有加成性。2)瞭解抗氧化劑增補對魚油與運動引致氧化性壓力，是否有減輕消除的效果，俾使運動與魚油皆能充分發揮對健康的好處。研究以33位未曾接受過運動訓練之健康男性，依平衡次序分為8組：運動組、運魚組、運抗組、三合組、魚油組、抗氧組、魚抗組及控制組。研究者操控運動、魚油及抗氧化劑，分別以單純或同時介入之不同條件；運動者得接受2次近乎衰竭的間歇運動評估；魚油組與抗氧化劑組，每日服用魚油9公克、500mg維生素C及400IU維生素E錠片並持續四週。運動前後均抽血檢驗：包含TAA(total antioxidant ability)、SOD(superoxide dismutase)、t-GSH(total glutathione)、GSH-Px(glutathione peroxidase)、MDA(malondialdehyde)等濃度或活性、維生素C、E及血脂質濃度。所得資料採用廣義估計方程式(generalized estimating equations，GEE)分析各依變項間之差異顯著性。

四週實驗前後，八組受試者身體型態及組成沒有明顯差異。由於統計分析顯示運動、魚油及維生素三者不存在交互作用，故影響效應具有加成性。抗氧化方面：魚油組SOD活性較未服明顯多11.27 kU/g-HB（P<.05），魚抗組及三合組SOD之加成效益亦明顯較多（P <.05）足見魚油對SOD有顯著影響。運動、魚油及維生素三者對TAA、GSH-Px均不具影響力。抗氧化物質：魚油組與運魚組之t-GSH分別明顯多及36.61(34.2％)及37.03Ug/ml（P <.05）。除單純運動或魚油分別造成MDA明顯增加0.12及0.27 nmol/ml（P <.05）外，運魚組、魚抗組及三合組之MDA加成均明顯增加（P <.05）且以三合組的增幅42.9％最多。血脂質評估方面：魚油組之TG顯著減少8.85 mg/dl（P <.05），證明操控的魚油劑量確實已造成生理的顯著效果。

結論：單純一次衰竭性激烈運動及單純服用魚油四週後，造成相當程度的氧化壓力，致脂質過氧化壓力明顯昇高；且兩者同時介入具加成性；抗氧化系統亦隨之部份打調昇現象。單獨或併服抗氧化劑，對運動與魚油引致之氧化性壓力，不具有消除的效益，原因尚待進一步的研究釐清。Exercise can improve performance, fitness, and metabolism, as well as modify body-fat ratio. But high-intensity exercise may also induce active oxygen species (AOS). Fish oil, which is one of the ω-3 PUFA series that can decrease TG and influence other plasma lipids, appears to prevent arteriosclerosis and CHD, but some evidence suggests it increases the lipid peroxidation in the cell membrane. Fish oil would then seem to influence the antioxidant defense system that causes injury or disease. This study investigates the effects on the antioxidant defence system of combining high-intensity exercise with fish oil supplementation. Thirty-three healthy males were randomly assigned into eight groups (20.3±1.4 yrs; 64.3±7.9 kg), which were givenset combinations of dietary fish oil (9 g per day), exercise (intensity 85-90 % HRmax reserve), anti-oxident supplementation (500 mg Vitamin C and 400 IU Vitamin E per day), and placebos. The experiment lasted 4 weeks in total. Venous samples were obtained prior to exercise and within 5 min after. 4 venous samples were also taken from fish oil groups during the four-week period. Blood from all groups was analyzed for sesuperoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total glutathione (T-GSH), total antioxidant ability (TAA), malodialdehyde (MDA), vitamin C& E, TG, HDL-C, LDL-C from forearm vein. A Generalized Estimating Equations (GEE) method was used for data analysis. Result: in no group was there a significant change in the body weight and body composition of the subjects. In the fish oil groups SOD activity significantly increased 11.27 kU/g-HB（P<.05）. Fish oil and vitamin C & E groups saw a decrease in GSH-Px levels, which did not appear in the exercise groups. However, statistical evidence is not sufficient to draw solid conclusions inthis area. MDA change increased significantly after exercise in both exercise and dietary fish oil groups (values: 0.12 and 0.27 mmole/ml [P<.05] respectively). The evidence shows that the dosage of fish oil decreased the values of LDL-C and TG (-4.61 mg/dl and -8.85 mg/dl [P <.05] respectively). Exercise increased LDL-C levels (+2.27 mg/dl). Following exercise in the fish oil group, t-GSH increased significantly (36.61Ug/ml [34.2%] [P<.05]). MDA increased significantly after exercise in both exercise-alone and exercise/fish oil groups (+0.12 and +0.27 mmole/ml [P<.05] respectively). Height intensity exercise and fish oil is a realfactor that induced more oxidative stress in this study. There is not sufficient evidence to support the claim that oxidative stress decreases after antioxidant supplementation, although there is some indication that this may be true. More research is required. The study concludes that exercise and fish oil separately causes an increase in oxidative stress, and this increase is greater when they are combined. It is also conclude that antioxidant supplementation has no effect on oxidative stress, although it is possible that a larger dosage may produce such an effect.