全靜脈營養輸入不同脂肪乳劑後對敗血症老鼠代謝之影響

Effects of parenterally infused different fat emulsions on metabolism in septic rats

趙哲毅(Chao Che-Yi)

指導教授 ： 葉松鈴

臺北醫學大學/公共衛生暨營養學院/保健營養學研究所/碩士(1998年)

摘要

敗血症(sepsis)是臨床上死亡率極高的症狀，當細菌之毒素侵入體內時會造成營養素代謝異常，如高三酸甘油酯血症、脂肪肝、組織分解等顯示，中鏈三酸甘油酯( medium chain triglyceride , MCT )在血中清除率較快對 ? ,>?s ??敗血症(sepsis)是臨床上死亡率極高的症狀，當細菌之毒素侵入體內時會造成營養素代謝異常，如高三酸甘油酯血症、脂肪肝、肌 之影響。實驗 fZ 可能是較好的選擇，但其他代謝上之利弊則未知。故本研究之目的在探討全靜脈營養輸入不同脂肪乳劑? ,>?s ??敗血症(sepsi 異常，如高三酸甘油酯血症、脂肪肝、肌肉組織分解等，近年來有研究顯示在敗血症發生 前給予老鼠富含魚油的飲食可以防止敗血症所引致的脂肪肝。但魚油以全靜脈營養 ( total parenteral nutrition , TPN )方式輸入是否有相同效果則尚無研究。另外也有 研究顯示，中鏈三酸甘油酯( medium chain triglyceride , MCT )在血中清除率較快對 敗血症病人可能是較好的選擇，但其他代謝上之利弊則未知。故本研究之目的在探討 全靜脈營養輸入不同脂肪乳劑後對敗血症老鼠代謝之影響。實驗係將Wistar雄性大白鼠 隨機分為三組，分別為紅花籽油組、魚油組及MCT組，禁食一夜後進行頸靜脈插管手術， 每組輸入之TPN溶液營養素比例均完全相同只有脂肪乳劑不同，輸入之熱量為30 kcal/100 g 體重，實驗期為七天。第七天將各組再分成控制組與敗血症組，敗血症是以盲腸結紮及穿刺 ( cecal ligation and puncture , CLP )引致，CLP手術後24小時將老鼠犧牲並抽血取肝臟 及腹水分析。實驗結果顯示，在血漿胺基酸方面，三組敗血症組之arginine均顯著低於控制組，而glutamine及支鏈胺基酸則敗血症與控 將Wistar雄性大白鼠隨機分為三組，分別為紅花籽油組、魚油組及MCT組，禁食一夜後進行頸靜脈插管手術，每組輸入之TPN溶液營養素比例均完全相同只有脂肪乳劑不同，輸入之熱量為30 kcal/100 g體重，實驗期為七天。第七天將各組再分成控制組與敗血症組，敗血症是以盲腸結紮及穿刺( cecal ligation and puncture , CLP )引致，CLP手術後24小時將老鼠犧牲並抽血取肝臟及腹水分析。實驗結果顯示，在血漿胺基酸方面，三組敗血症組之arginine均顯著低於控制組，而glutamine及支鏈胺基酸則敗血症與控制組無差異，顯示對敗血症而言血漿arginine之下降可能是較敏 之指標。血漿脂質方面，MCT敗血症組血漿TG顯著較控制組高，魚油及紅花籽油敗血症組之血漿TG則與其控制組無統計上之差異；而魚油組的血漿膽固醇不論在控制組及敗血症組均較其他二組為低。肝臟脂質方面，在敗血症組中紅花籽油組及MCT組之肝臟總脂質均顯著較其控制組高，魚油敗血症組之肝臟總脂質則與其控制組無統計上之差異，而魚油敗血症組則顯著較紅花籽油敗血症組為低，且與MCT敗血症組無統計上差異，並且魚油組其肝臟Glutathione peroxidase活性不論在控制組或敗血症組均顯著低於紅花籽油組及MCT組，顯示魚油輸入並未造成脂質過氧化物的堆積。由以上 果顯示，對TPN之敗血症病人而言魚油乳劑可能是較MCT及紅花籽油乳劑較佳的選擇。

關鍵字

全靜脈營養 ； 脂肪乳劑 ； 敗血症 ； 胺基酸組成 ； 脂肪肝

並列摘要

Sepsis is one of the major causes of death for most critically ill patients. Clinically, it is characterized by fever, hypotension, and organ hypoperfusion or dysfunction. When the toxin of bacteria insults, abnormal nutrient metabolism would happen, such as hypertriglyceridemia, fatty liver, weight loss and muscle tissue breakdown etc. The mechanisms are not fully understood at present. Recently, stu癢? showed that feeding rats with a fish oil diet before inducing sepsis prevents fatty infiltration of he liver. Since the nutrients composition and feeding route were different between total parenteral nutrition (TPN) and oral feeding, whether fish oil infusion by the route of TPN may have the same effect as oral intake remains unknown. Medium chain triglyceride (MCT) has found increasing acceptance in parenteral nutrition in later years. Previous reports revealed that the clearance rate in plasma is faster in MCT than that of the long chain triglyceride, however, the effect of MCT on plasma lipids in se ic patients is unclear. Therefore, the purpose of this study is to investigate the effects of parenterally infused three different fat emulsions on nutrient metabolism in septic rats. Fifty male Wistar rats with right internal jugular vein cannulation were divided into 3 experimental groups. The three groups received TPN solution at energy level of 30 kcal/100g body weight. All of the basal TPN solution were isonitrogenous and identical in nutrients composition except for the difference in fat emulsions which were prepared with safflower oil, MCT oil and fish oil. The TPN was kept for seven days. After then, each experimental group was further divided into septic and control subgroup The rats in septic subgroups were induced by cecal ligation and puncture, the rats in control subgroups received sham operation. After fast for 24 hours, all rats were sacrificed by drawing arterial blood from the aorta. The livers of the rats were excised and peritoneal lavage fluid were collected for further analysis. The results demonstrated that plasma arginine concentration was significantly lower in the septic subgroups compared with the control subgroups. No significant differences in plasma glutamine and branch-chain amino acids levels were observed in the sepsis and the control subgroups. Plasma TG was significantly higher in the MCT-septic subgroup than in the corresponding group without sepsis. Plasma cholesterol in fish oil group was the lowest among the all groups. Among the sepsis subgroups, safflower oil nfusion resulted in higher lipid accumulation in the liver than that of the MCT and fish oil infusion. Glutathione peroxidase activity in liver homogenate was significantly lower in fish oil subgroup than the other two subgroups in either sepsis or control rats. The results suggest that plasma arginine concentration is a more sensitive indicator than glutamine and branch chain amino acids in the diagnosis of sepsis. Preinfusion of fish oil neither induce significant elevation of plasma lipids nor did liver fat accumulation. It is suggested that fish oil is a favorable source of fat for the septic patients.

並列關鍵字

TPN ； Fat emulsion ； Sepsis ； Amino acid pattern ； Fatty liver