維生素 C 與 E 的補充增強血液透析患者血漿總 抗氧化狀態與減少血漿脂質過氧化物濃度
研究指出慢性腎衰竭患者隨著血液透析或連續式攜帶型腹膜透析的治療，會造成氧化壓力的增加。而目前對於給予 血液透析患者口服抗氧化補充劑對抗氧化系統整體影響與時間效應並不十分清楚。因此本研究的目的主要是評估血 液透析患者的飲食攝取與健康受試者是否有差異，及探討維生素 C 或 / 與 E 的口服補充對血液透析患者抗氧化防禦 系統的影響，及追蹤在停止維生素 C 或 / 與 E 的補充後，血液透析患者體內的抗氧化能力。本研究以臺北醫學大學 附設醫院血液透析中心門診常規血液透析病患為對象，經過篩選後，將 38 位患者平均分為四組：安慰劑 (400 mg 澱粉 / 次 ) 組、維生素 C ( 400 mg L- ascorbic acid / 次 ) 組、維生素 E (400 mg d,l-α-tocopheryl acetate/ 次 ) 組、維生 素 C ( 400 mg L- ascorbic acid/ 次 ) + 維生素 E (400 mg d,l-α-tocopheryl acetate/ 次 ) 組，為期六週。於每次血液透析 結束後，直接給予患者口服安慰劑或抗氧化補充劑共三顆膠囊，每週三次，血液透析患者於補充前 ( 第零週 ) 、補 充期間 ( 第三週 ) 、補充後 ( 第六週 ) 、追蹤期間 ( 第七、八週 ) 與追蹤後 ( 第十週 ) ，在血液透析前、後各抽血分析。
另以年齡分布與性別比例相似之健康受試者 36 人做為對照組。本實驗結果顯示：血液透析患者其飲食攝取與健康受 試者無統計上的差異，且血液透析患者之飲食攝取量，並不受補充劑種類或補充時間的影響，表抗氧化效果的差異
，由抗氧化維生素補充所造成。血液透析患者血漿中維生素 C 含量顯著低於健康受試者，透析後較透析前顯著下降 達 24% ，表透析過程中維生素 C 會大量流失，給予抗氧化補充劑三週後於維生素 C 與 C + E 組較補充前顯著提昇；
血漿中維生素 E 含量與健康受試者無差異，給予抗氧化補充劑六週後，於維生素 E 與維生素 C + E 組較補充前顯著 提昇；另患者紅血球中麩胱甘 的含量顯著的低於健康受試者，血液透析後與透析前並無統計差異，給予抗氧化補 充劑六星期後皆較安慰劑組與補充前顯著的提昇。血漿總抗氧化狀態在血液透析前比正常值低者佔 29% ，血液透析 後比正常值低者佔 100% 。顯示血液透析四小時治療過程中，會造成體內氧化壓力的增加，降低體內總抗氧化狀態
；就組間效果上而言，補充三週後血漿總抗氧化狀態在維生素 C + E 組顯著大於維生素 C 組，與維生素 E 組則無差 異；血液透析患者血漿中脂質過氧化物 (malondialdehyde; MDA + 4-hydroxy-2(E)-nonenal; 4-HNE) 的濃度顯著高於健 康受試者，於血液透析前與透析後相比則無顯著差異；給予抗氧化補充劑六週後血漿中脂質過氧化物濃度皆較補充 前顯著下降。總而言之，接受血液透析治療患者口服補充抗氧化維生素 C 或 / 與 E 六星期，可提高體內抗氧化狀態
，減少脂質過氧化物的產生。
關鍵詞：維生素 C 、維生素 E 、抗氧化狀態、脂質過氧化、血液透析
Vitamin C and E Supplementation Enhances Plasma Total Antioxidant Status and Decreases Plasma Lipid Peroxide
Concentrations in Hemodialysis Patients
It has been reported that chronic renal failure patients with hemo- or continuous ambulatory peritoneal dialysis increase oxidative stress. However, it w as not clearly known that the effects of oral antioxidant supplement on the overall antioxidant system and time course study in hemodialysis patients. T his study was to evaluate if dietary intake was different between hemodialysis patients and healthy subjects, and to investigate the supplementation wit h vitamin C or/and E on antioxidant capacity in hemodialysis patients. The patients routinely receiving hemodialysis were recruited from the center of hemodialysis at Taipei Medical University Hospital. After screening, thirty-eight patients were divided into four groups: placebo (400 mg starch/time), vitamin C- (400 mg/time), vitamin E- (400 mg d,l-a-tocopheryl acetate/time), and vitamin C (400 mg/time) + E (400 mg d,l-a-tocopheryl acetate/tim e)-supplemented groups for 6 weeks. The patients orally received three capsules three times a week right after finishing hemodialysis. Blood samples f rom pre- and post-dialysis were drawn before (week 0), during (week 3), and after (week 6) supplementation, as well as during (week 7, 8) and after (week 10) follow-up. Additionally, thirty-six healthy subjects with similar age and sex distribution were selected as the control group. The results sho wed that dietary intake was not significantly different between hemodialysis patients and healthy subjects. Both antioxidant supplements and suppleme nted duration did not affect dietary intake of hemodialysis patients, indicating the difference of antioxidant capacity resulted from antioxidant supplem ents. Plasma vitamin C concentration was significantly decreased in hemodialysis patients compared with healthy subjects, and significantly lowered b y 24% from post-dialysis compared with pre-dialysis, suggesting vitamin C was greatly lost during hemodialysis. After 3-week antioxidant supplement ation, vitamin C- and vitamin C + E-supplemented groups significantly elevated plasma vitamin C levels compared with those at the baseline. Hemodi alysis patients had similar plasma vitamin E concentration as healthy subjects. Plasma vitamin E concentrations were significantly higher in vitamin E- and vitamin C + E-supplemented groups at week 6 than those at week 0. Erythrocyte glutathione levels were also lower in hemodialysis patients than i n healthy subjects, but were not significantly different between post- and pre-dialysis. All antioxidant supplements elevated erythrocyte glutathione at week 6 compared with placebo group and the baseline. Total antioxidant status was lower than the normal range in 29% hemodialysis patients from pr e-dialysis, and in 100% hemodialysis patients from post-dialysis, indicating increased oxidative stress and impaired total antioxidant status during 4-h hemodialysis. Vitamin C + E-supplemented group had higher total antioxidant status than vitamin C-supplemented group at week 3, but had similar le vel as vitamin E-supplemented group. Hemodialysis patients had greater plasma lipid peroxide (malondialdehyde; MDA + 4-hydroxy-2(E)-nonenal; 4- HNE) levels than healthy subjects, but no significant difference was found from post- and pre-dialysis. All antioxidant supplements decreased plasma l ipid peroxides at week 6 compared with at the baseline. Therefore, oral supplementation with vitamin C or/and vitamin E for 6 weeks could improve a ntioxidant status and decrease lipid peroxide production in hemodialysis patients.
