- 學位論文
補充綜合抗氧化營養素增強高血脂症抽煙者的抗氧化酵素活性與減少血漿及低密度脂蛋白脂質的過氧化
Supplementation with combined antioxidant vitamins enhance antioxidative enzyme activities and decrease lipid peroxidation in plasma and LDL
摘要
抽煙會使身體主動防衛系統中所貯備的抗氧化維生素很快的消耗，且身體所受的氧化壓 力隨之增加，如果不能維持過氧化物與抗氧化物的平衡，又缺乏抗氧化營養素的補充，體 內自由基的生成增加，便造成脂質過氧化作用的發生。然而早期動脈硬化病灶的泡沫細胞 形成原因與血液中膽固醇濃度過高和低密度脂蛋白(low density lipoprotein；LDL)的氧 化有密切的關係。故本研究目的在於瞭解補充綜合抗氧化營養素(B-胡蘿蔔素＋維生素 C ＋維生素E ) 對高血脂症抽煙者的血脂質濃度、抗氧化能力和血漿與低密度脂蛋白脂質氧 化的影響；並且進一步探討綜合抗氧化營養素補充的劑量多寡和補充時間的長短不同對高 血脂症抽煙者之影響程度。本實驗以人為研究對象，受試者均來自台北醫學院附設醫院和 台北市立萬芳醫院內科病人，經醫師診斷為高血脂症者。共有42位抽煙男性參與研究，隨 機分為低劑量組和高劑量組。低劑量組每天補充15 mg (B-胡蘿蔔素/天＋500 mg維生素C/ 天＋400 mg 維生素E/天；高劑量組每天補充30 mg (B-胡蘿蔔素/天＋1000 mg維生素C/天 ＋800 mg 維生素E/天，共六星期。受試者每三個星期回診一次，並於實驗期間第零星期 、第三星期、第六星期記錄二十四小時飲食回憶記錄和空腹抽血。研究期間補充綜合抗氧 化營養素對高血脂症抽煙者之血壓，總三酸甘油酯、總膽固醇、高密度脂蛋白膽固醇、低 密度脂蛋白膽固醇均無影響。抗氧化酵素系統中的超氧化歧化酵素(superoxide dismutas e；SOD)和麩胱甘太過氧化酵素(glutathione peroxidase；GSH-Px)的活性均隨著抗氧化 營養素補充時間的增長而顯著上升，但高劑量組和低劑量組的上升程度相似。與實驗前相 較，第六星期時低、高劑量組SOD活性顯著分別上升213%和77%。GSH-Px活性於高劑量組第 三星期與第六星期分別比實驗前升高67%和81%，然而低劑量組於實驗期間GSH-Px活性並無 明顯改變。血漿中脂質過氧化物(malondialdehyde；MDA＋4-hydroxy-2(E)-nonenal；4-H NE)的濃度於低劑量組第三星期比實驗前降低16%；高劑量組第六星期比實驗前降低17%。 兩組低密度脂蛋白中脂質過氧化物(MDA+4-HNE)的濃度也隨著抗氧化營養素補充時間的延 長而下降。高劑量組於第三星期時，低密度脂蛋白中脂質過氧化物濃度比實驗前降低46% ；第六星期時低劑量組與高劑量組之低密度脂蛋白中脂質過氧化物濃度分別比實驗前降低 56%和72%。補充綜合抗氧化營養素三星期後，高劑量組體內總抗氧化狀態(total radical -trapping antioxidant parameter calculation；TRAPc)比實驗前上升9%；六星期後低 、高劑量組體內總抗氧化狀態分別比實驗前上升32%和23%。因此，補充綜合抗氧化營養素 六星期就能有效提升高血脂症抽煙者體內抗氧化酵素的活性、體內總抗氧化狀態和降低血 漿、低密度脂蛋白中脂質過氧化物含量。除了GSH-Px (p=0.008)外，高劑量組與低劑量組 的效果相似。
並列摘要
Smoking can accelerate the consumption of the stored antioxidant vitamins in the body and increase oxidative stress. If the body maintains an imbalance be tween pro-oxidants and antioxidants and lacks the supplementation of antioxida nt nutrients ,it may result in increased free radical f?YTtion and lipid pero xidation. It is reported that the formation of foam cells in the early stage of atherosclerosis was closely related to elevated blood cholesterol and oxidi zed low density lipoprotein (LDL). The purpose of this study was to determine the effects of antioxidant vitamin supplementation ((-carotene + vitamin C + vitamin E) on plasma lipids, antioxidant capacity, and lipid peroxidation in p lasma and LDL in hyperlipidemic smokers. Furthermore, the dosage and the dura tion of the supplementation were studied. The subjects were recruited from th e patients of internal medicine in Taipei Medical Hospital and Taipei Wan Fang Hospital, and diagnosed as hyperlipidemia by the physicians. Forty-two male hyperlipidemic smokers were randomly divided into either low (LA, n = 22) or h igh antioxidant group (HA, n = 20). The subjects consumed 15 mg (-carotene/d, 500 mg vitamin C/d, and 400 mg (-tocopherol/d, or 30 mg (-carotene/d, 1000 m g vitamin C /d, and 800 mg (-tocopherol/d in the LA and HA groups, respectivel y, for 6 weeks. The patients were followed every 3 weeks. The 24-h dietary r ecall was recorded and blood samples after overnight fasting were drawn at wee k 0, 3, and 6. The supplementation of antioxidant vitamins had no effects on blood pressure, total triglycerides, total cholesterol, HDL-cholesterol, and L DL-cholesterol in hyperlipidemic smokers. The activities of superoxide dismut ase (SOD) and glutathione peroxidase (GSH-Px) were elevated with increased dur ation of the supplementation. However, no differences between the LA and HA g roups were observed. The activity of SOD was respectively elevated by 213% an d 77% at week 6, as compared to the corresponding baselines, in the LA and HA groups. The activity of GSH-Px was increased by 67% and 81% at week 3 and 6,r espectively, as compared to the baseline in the HA group. However ,no changes were observed in GSH-Px activity of the LA group. The plasma levels of malon dialdehyde (MDA) and 4-hydoxy-2(E)-nonenal (4-HNE), lipid peroxidation product s, were decreased by 16% in the LA group at week 3, and decreased by 17% in th e HA group at week 6. Lipid peroxidation in LDL was decreased with increased duration of the supplementation in both groups. Lipid peroxidation in LDL wa s decreased by 46% in the HA group at week 3, and by 56% and 72% at week 6 in the LA and HA groups, respectively, as compared to the corresponding baselines . Total radical-trapping antioxidant parameter(TRAP) levels were increased by 9% in the HA group at week 3 , and by 32% and 23% at week 6 in the LA and HA groups ,respectively, as compared to the baselines. Therefore, hyperlipidemic smokers had increased antioxidative enzyme activities, decreased lipid perox idation in plasma and LDL, and elevated TRAP levels after 6-week supplementati on of antioxidant vitamins. However, except for GSH-Px. activity similar effe cts of high and low doses of the supplementation were found .