不同脂肪乳剂对阻塞性黄疸大鼠肝功能和形态学的影响

研究 TPN中不同的脂肪乳剂对阻塞性黄疸肝损大鼠肝形态学和功能的影响 ,为临床此类病人营养支持时选择TPN配方提供依据。取 Sprague- Dawley封闭群大鼠 36只 ,体重为 30 0～ 35 0 g。实验前适应性饲养一周。随机分为 4组 ,每组 9只。其中 A组 :假手术经口饮食对照组 (SHAM-对照组 )、B组 :胆总管结扎经口饮食对照组 (CBDL-对照 )、C组 :胆总管结扎 TPN组 ,以长链脂肪酸为脂肪来源 (CBDL+L CT)、D组 :胆总管结扎 TPN组 ,以中长链脂肪酸为脂肪来源 (CBDL+MCT/ L CT)。分别于 TPN0、72 h和 12 0 h处死。处死前采血 ,检测肝…     

肠外营养中脂肪乳剂对红细胞膜磷脂脂肪酸组成的影响

利用大鼠胃肠外营养(PN)模型观察长链脂肪乳剂(LCT),中链/长链脂肪乳剂(MCT/LCT),以及不含脂肪乳剂对红细胞(RBC)膜磷脂肪酸组成的影响。PN总热量为300kcal.kg~(-1).d~(-1),非蛋白热卡:氮为182:1,LCT组,MCT/LCT组分别由10％的Intralipid和10％的Lypofundin提供30％的非蛋白热卡。7天后,分析RBC膜磷脂酰二极管胆硷(PC)脂肪酸组成。结果发现,不含脂肪乳剂组18:1n-9明显高于对照组;LCT组18:2n-6升高,而20:4n-6却下降;MCT/LCT组与对照组相比,脂肪酸组成变化不明显。结论:无脂肪乳剂TPN导致必需脂肪酸缺乏;LCT组由于18:2n-6的过量供给,抑制Δ6去饱和酶的活性,MCT/LCT组由于50％LCT被MCT替代,减低了对此酶活性抑制。     

肠外营养中脂肪乳剂抑制肝脂肪变性的机理

210克左右Wistar大鼠随机分为五组，在LCT组、MCT／LCT组、GS组中进行等氮、等热量肠外营养（PN）。总热量为300kcal·kg－1·d-1，非蛋白热能：氮＝182：1，LCT组、MCT／LCT组分别由10％的Intralipid和10％的Lipofundin提供30％的非蛋白热卡，7天后，分别测定血脂和肝脂，测定血浆生化指标，并行肝脏病理检查。结果显示：GS组肝细胞胞浆内出现弥漫的脂肪浸润，而LCT组、MCT／LCT组的肝细胞与对照组类似，无脂肪变性。探讨PN中脂肪乳剂抑制肝脂防变性的机理，是由于脂肪乳剂中必需脂肪酸（EFA）使肝脏内的脂肪合成减少，脂肪运出增加，通过代谢调节避免了肝脏脂肪变性。     

新生儿肝功能障碍时不同脂肪乳剂对血脂和肝功能影响的比较研究

目的 :比较中 /长链和长链脂肪乳剂对肝功能障碍新生儿血脂和肝功能的影响。　方法 :将 40例血清胆红素水平≥ 5 1.3μmol/L(3mg % )的新生儿随机分成两组 ,分别应用中 /长链脂肪乳剂 (MCT/LCT组 ,2 0 %Lipo fundin)和长链脂肪乳剂 (LCT组 ,2 0 %Intralipid) ,剂量均为 2 g/ (kg·d) ,持续 1周。在实验前、后分别抽血测定血脂和肝功能。　结果 :两组总胆固醇无显著变化 ,甘油三酯在LCT组升高 ,在MCT/LCT组下降 ,与实验前相比均无显著差异 ,组间比较MCT/LCT非常显著地低于LCT组。胆红素在两组均显著下降 ,但MCT/LCT组下降比LCT组更加显著。γ GT和ALP在LCT组无明显改变 ,但在MCT/LCT组却有显著降低 ,并显著低于LCT组。　结论 :在危重新生儿合并有肝功能障碍时 ,应用中 /长链脂肪乳剂显著优于长链脂肪乳剂。     

肠外营养中脂肪乳剂对红细胞变形性的影响

利用大鼠胃肠外营养（PN）模型观察长链脂肪乳剂（LCT），中链／长链脂肪乳剂（MCT／TCT），以及不含脂肪乳剂对红细胞变形性的影响。PN总热量为300kcal·kg-1·d-1，非蛋白热卡：氮为182：1，LCT组、MCT／LCT组分别由10％Intralipid和10％Lipofundin提供30％的非蛋白热卡。7天后，分析红细胞膜磷脂脂肪酸组成和用激光衍射法测定红细胞变形性。结果发现，尽管红细胞膜磷腊脂肪酸组成发生改变，由于脂肪酸饱和度变化不大，红细胞变形性无改变。     

静脉输注长链或中长链脂肪酸脂肪乳剂对急性坏死性胰腺炎大鼠脂质介质的影响

目的：探讨静脉输注长链或中长链脂肪酸脂肪乳剂对急性坏死性胰腺炎（ANP）大鼠血浆脂质介质及胰腺病理改变的影响。方法：雄性SD大鼠43只随机入组，A－C为非胰腺炎组：A组为正常组；B组正常大鼠输注脂肪乳剂；C组为手术对照组，输注葡萄糖液。D－F为ANP模型组：分别为全糖组，Intralipid组和Lipofundin组。测定A组血淀粉酶、前列腺素类，胰腺行病理学检查。测定B－F组术后4、48及72h血淀粉酶、前列腺素类，胰腺病理学检查并评分。结果：正常大鼠输注Intralipid不引起血前列腺素的变化。在胰腺炎各组，脂肪乳剂可提高4h6－keto-PGF1α、PGE2血浆浓度；Lipofundin组胰腺组织的出血和脂肪坏死明显减少。结论：脂肪乳剂不加重ANP大鼠胰腺组织病理损害；LCT／MCT脂肪乳剂更适合应用于ANP。     

含维生素E的中/长链脂肪乳注射液临床应用进展

脂肪乳剂是全胃肠外营养(TPN)中的重要组成部分.随着TPN在临床营养治疗中的广泛应用,脂肪乳剂也逐渐由长链脂肪乳(LCT)发展至中/长链脂肪乳(MCT/LCT).MCT具有水解、氧化快而完全,不依赖肉毒碱转运,对免疫系统影响少,且不易在肝内和外周组织中浸润等优点.但其中仍含有一定量的多不饱和脂肪酸,易受体内自由基的攻击而产生脂质过氧化,进而损害脂质、DNA和蛋白质,造成组织和器官的损伤.因此,许多学者主张在MCT/LCT剂中添加一定量的维生素E,以防止脂肪乳剂脂质过氧化的发生,从而保证临床安全、合理地使用脂肪乳剂进行营养治疗的同时,有效地避免发生不良反应.以下主要对含维生素E的MCT/LCT注射液在临床的应用作一综述.     

不同碳链脂肪乳剂对肝脏外科病人术后的影响

目的观察两种不同碳链脂肪乳剂对肝脏外科病人术后自然病程的影响。方法选择肝脏外科病人25例，随机分为两组；长链脂肪乳剂组（n＝12，简称LCT组），中／长链脂肪乳剂组（n=13，简称MCT组）。LCT组脂肪乳剂为20％Inralipid，MCT组为20％Lipofundin，连续观察1周。在术前，术后1、4、7天测定肝功能、血脂、血及尿液中肉毒碱（CNT）以及激素的变化。结果两组对肝脏酶学无明显影响。胆红素在术后1天明显升高，但MCT组随后显著下降，LCT组下降速度慢于MCT组，P＜0．05。PN期间血脂代谢无异常。CNT术后明显升高，尿排出减少，术后7天LCT组血CNT高于MCT组，尿CNT低于MCT组，P＜0．05。血皮质醇、胰岛素（I）、G以及G／I术后第1天均明显升高，随后逐渐下降，而LCT组术后7天，胰高糖素（G）以及G／I维持在较高水平。血糖术后明显升高，术后4、7天，LCT组持续在较高水平，MCT组已属正常。结论MCT／LCT乳剂可能是肝脏外科病人更为理想的脂肪能源。     

中链甘油三酯饮食增加过氧化物酶增殖体激活受体γ和脂联素的表达

目的探讨含中链甘油三酯(medium chain triglycerides,MCT)的高脂饮食对血清和脂肪组织中脂联素、过氧化物酶增殖体激活受体γ(PPARγ)水平的影响。方法雄性Wistar大鼠,分别饲喂含MCT和长链甘油三酯(LCT)的高脂饲料,8w后病理检测右侧肾周脂肪细胞的大小。ELISA法检测血清中脂联素、TNF-α、胰岛素的水平。逆转录PCR测定脂肪组织中脂联素、PPARγ mRNA表达水平。结果MCT组大鼠体脂(BFA)、外周脂肪组织的细胞直径小于LCT组。MCT组的血清脂联素含量高于LCT组,两组间血清TNF-α无显著差异。MCT组外周脂肪组织中脂联素、PPARγ mRNA表达水平显著高于LCT组。结论MCT饮食可通过促进PPARγ表达,上调脂联素基因的表达,改善大鼠胰岛素抵抗。     

不同氨基酸对淤胆鼠肠粘膜形态学的影响

研究不同氨基酸来源的 TPN配方对阻塞性黄疸大鼠肠粘膜形态学的影响。取 Sprague- Dawley封闭群大鼠 45只 ,体重为 30 0～ 35 0 g,适应性饲养一周后 ,随机分为 5组 ,每组9只。 A组 :假手术经口饮食对照组 (SHAM-对照组 )、B组 :胆总管结扎经口饮食对照组 (CBDL-对照组 )、C至 E组为胆总管结扎加 TPN组 ,其中 C组 (CBDL+15 )以 15 -氨基酸80 0为氮源、D组 (CBDL+N)以 NOVAMIN为氮源、E组(CBDL+G)以 GL AMIN为氮源。各组 TPN为等氮、等热量。总热量为 710 .6 k J(170 kcal) / (kg· d) ,其中 30 %热量由脂肪提供 ,5 5 %…     

MCT/LCT emulsion ameliorate liver fat deposition in insulin-treated diabetic rats receiving total parenteral nutrition

This study was designed to investigate the effects of high energy infusion and insulin treatment on plasma and liver lipids in diabetic rats receiving total parenteral nutrition (TPN). Diabetes was induced in rats by streptozotocin. The diabetic rats were assigned to two TPN groups to receive either long chain triglyceride (LCT) or medium chain triglyceride (MCT)/LCT (1:1) as a fat source. The TPN solutions were isonitrogenous, isocaloric and identical in nutrient composition except for the fat emulsion. All rats received the TPN solution at an energy level of 35|kcal/100|g of body weight. The LCT and MCT/LCT groups were further divided into two subgroups, depending on whether they were treated with insulin. The results demonstrated that, between the MCT/LCT and LCT groups, no differences were observed in body weight and nitrogen retention, as well as the concentrations of plasma glucose, nonesterified fatty acids, beta-hydroxybutyrate, and total cholesterol. Diabetic TPN rats without insulin treatment had weight loss and negative nitrogen balance during the experiment. Diabetic TPN rats treated with insulin, however, demonstrated less weight loss and positive nitrogen retention. Insulin treated groups had significantly higher liver fat content than did those without insulin treatment. Furthermore, liver fat content was significantly higher in the LCT group than in the MCT/LCT group among insulin treated TPN rats. These results suggest that compared with the LCT emulsion, infusion of the MCT/LCT emulsion ameliorated liver fat deposition in insulin-treated diabetic rats receiving TPN.     

Effects of medium-chain triglyceride in parenteral nutrition on rats undergoing gastrectomy

This study was designed to investigate the effects of pre-infusion with total parenteral nutrition (TPN) using medium-chain triglyceride (MCT) versus long-chain triglyceride (LCT) emulsion as fat sources on hepatic lipids, inflammatory mediators and antioxidant capacity in rats undergoing gastrectomy. Rats with internal jugular catheter, were divided into two groups and received TPN. TPN supplied 300 kcal/kg/d with 39% of the energy provided as fat. All TPN solutions were isonitrogenous and identical in nutrient composition except for the fat emulsion, which was composed of MCT/LCT (1 : 1) or LCT. After receiving TPN for 5 days, the rats underwent partial gastrectomy and were sacrificed 24 h after surgery. The results of the study demonstrated that the MCL/LCT group had lower hepatic lipids than did the LCT group. No differences in interleukin-1beta, interleukin-6 and tumor necrosis factor-alpha in peritoneal lavage fluid were observed between the two groups. Erythrocyte glutathione peroxidase activity was significantly higher in the LCT group than the MCT/LCT group, although erythrocyte superoxide dismutase activity did not differ significantly between the two groups. These results suggest that infusion with MCT/LCT before an abdominal operation did not have an effect on modulating the production of inflammatory mediators in the location of the injurious stimulus. However, pre-infusion with MCT/LCT have beneficial effect in improving liver lipid metabolism and reducing oxidative stress in rats with gastrectomy.     

含中链甘油三脂的脂肪乳剂有利于胃切除术后大鼠的脂类代谢和抗氧化能力

研究胃切除大鼠于术前接受以中链甘油三酯或长链甘油三酯为脂肪来源的肠外营养对肝内脂类，炎性介质和抗氧化能力的影响。大鼠经颈内静脉插管，分成两组接受肠外营养治疗。肠外营养的能量为30kcal/kg/d， 脂肪占能量的39％。除了脂肪乳剂外所有肠外营养制剂都是等氮的并含有相同的营养成分，脂肪乳剂的成分中链／长链（1：1）或长链脂肪乳剂。大鼠于接受肠外营养5天后经部分胃切除术，于术后24小时处死。研究结果显示，中逻／长链组肝内脂肪少于长链组。提示中链／长链脂肪乳剂能改善肝脏脂类代谢。两组大鼠的腹腔灌洗液（PLF）和血液中白介素－1β（Ⅱ-1β），白介素－6（Ⅱ－6）和肿瘤坏死因子α（TNF－α）无显差别，说明术前输入中链／长链脂肪乳剂对调节大鼠循环血液中的炎性介质和手术刺激没有影响。长链脂肪乳剂组的红细胞谷胱甘肽超氧化物酶（GSHPx)的活力明显高于输入中链／长链脂肪乳剂组，但红细胞超氧化物歧化酶（SOD）的活力在两组之间无显性差别。这些结果说明，腹部手术前输入中链／长链脂肪乳剂能改善脂类代谢和减少氧化物的刺激。结论：推荐对准备行胃手术的肠外营养支持的病人使用中链／长链脂肪乳剂。     

Effect of various lipid emulsions on total parenteral nutrition-induced hepatosteatosis in rats

The effect of various lipid emulsions on the development of fatty liver during total parenteral nutrition (TPN) was investigated in rats given TPN for 7 days. Medium-chain triglycerides (MCT), long-chain triglycerides (LCT), chemically defined triglycerides (CDT; structured lipid with a high purity of 94.3%), and a mixture of MCT and LCT (MIX) were prepared as the lipid emulsions. TPN provided 350 kcal/kg/day, with a nonprotein calorie/nitrogen ratio of 160. The TPN-1 group received 10% nonprotein calories and the TPN-2 group received 30% nonprotein calories. MCT TPN was found to have some disadvantages, especially with regard to nitrogen balance and plasma albumin levels. Total cholesterol and phospholipids tended to be high in the MCT TPN group. The hepatic lipid content was higher in the lipid-free TPN and the MCT TPN groups, and lower in the CDT and LCT TPN groups. Histologically, the livers of the MIX, CDT, and LCT TPN groups showed less fatty change than those of the FREE and MCT groups.     

脂肪乳剂对完全胃肠外营养大鼠血清游离脂肪酸谱的影响

为研究脂肪乳剂对机体脂肪代谢的影响，用气相色谱法观测了完全胃肠外营养（ＴＰＮ）大鼠血清游离脂肪酸（ＦＦＡ）谱的变化。将４０只雄性Ｗｉｓｔａｒ大鼠随机分成５组，每组８只：（１）ＳＨ（Ｓｈａｍｏｐｅｒａｔｉｏｎ）组，仅进行颈外静脉结扎，正常饲养；（２）ＮＳ（Ｎｏｔｍａｌｓａｌｉｎｅ）组：正常饲养，输入生理盐水；（３）ＧＳ（Ｇｌｕｃｏｓｅ）组：全部能量由葡萄糖提供，即不含脂肪乳剂ＴＰＮ组；（４）ＬＣＴ（Ｌｏｎｇｃｈａｉｎｔｒｉｇｌｙｃｅｒｉｄｅ）组：含１０％Ｉｎｔｒａｌｉｐｉｄ脂肪轧的ＴＰＮ组；（５）ＭＣＴ（Ｍｅｄｉｕｍｃｈａｉｎｔｒｉｇｌｙｃｅｒｉｄｅ）组：含１０％Ｌｉｐｏｆｕｎｄｉｎ脂肪乳ＴＰＮ组。ＴＰＮ各组大鼠等能量等氮量等液量匀速连续输入“生合一”营养液（即将所有营养物混合在一个溶器内）。于第７天取血标本进行血清ＦＦＡ测定。结果表明：不含脂肪乳的ＴＰＮ大鼠血清各种ＦＦＡ下降，并出现必需脂肪酸缺乏（ＥＦＡＤ）症状，如精神不振活动少，毛发无光泽、脱落等；脂肪乳剂的使用，使大鼠血清各种ＦＦＡ升高，对机体的代谢和功能有着不同的生理、药理作用。     

Lipid and lipid-free total parenteral nutrition: differential effects on macrophage phagocytosis in rats

Lipid emulsions provided with total parenteral nutrition (TPN) have been associated with mononuclear phagocytic system functional changes. The aim of the present investigation was to assess the influence of TPN with added lipid emulsions on macrophage (M phi) phagocytosis. Wistar rats (n = 70) with external jugular vein cannulation were randomized into seven groups. The rats received an oral diet or six different isocaloric (1.16 kcal/mL), isonitrogenous (1.5 g/mL), and isolipidic (30% non-protein calories) TPN regimens: (a) an oral diet with intravenous infusion of saline (OS); (b) non-lipid TPN (glucose); (c) TPN with 10% long chain triacylglycerol emulsions (LCT); (d) TPN with 90% LCT and 10% fish oil (FO) emulsion; (e) TPN with 50% LCT and 50% FO; (f) TPN with 10% lipid emulsion with 50% medium chain triacylglycerol (MCT) and 50% LCT; and (g) TPN with 45% MCT, 45% LCT, and 10% FO. After 96 h of TPN or saline infusion, colloidal carbon (Pelikan, Germany) was injected intravenously at 1.0 mL/kg body weight, and the rats were killed after 3 h. Liver, spleen, and lung were weighed and prepared by immunohistochemistry analyses with the HAM-56 anti-M phi antibody. Under light microscopy, the total M phi number (MT) and the colloidal carbon phagocytic M phi number (MP) were established, and the phagocytic index was calculated as MP/MT x 100. There were no statistical (P < 0.05) differences in liver, spleen, or lung weights among the seven groups in comparison with the OS group. Non-lipid TPN inhibited spleen and lung M phi phagocytosis when compared with the OS and lipid-TPN groups. Lipid TPN supplemented with fish oil emulsion increased total liver and lung M phi number and phagocytosis. These results indicate that TPN supplemented with fish oil increases M phi phagocytosis in rats.     

Effects of medium-chain and long-chain triacylglycerols in pediatric surgical patients

Medium-chain triacylglycerols (MCTs) have been shown to provide better nutritional support than long-chain triacylglycerols (LCTs). This study compares the efficacy of MCT combined with LCT with LCT alone in pediatric patients with surgical stress. Two groups of patients (n = 19 in each) received equivalent amounts of glucose (12 g. kg. d) and amino acids (2 g. kg. d), but one group received 10% Lipofundin MCT/LCT and the other received 10% LCT (1.5 g. kg. d) in a randomized study. Total parenteral nutrition (TPN) was given for 14 d. Blood and urine samples were collected before and after TPN administration for determination of various biochemical parameters. Indirect calorimetry was also performed to determine respiratory quotients and fuel utilization. After 14 d of TPN in the MCT/LCT group, there was a significantly higher blood lymphocyte percentage, a decreasing tendency of serum asparate aminotransferase and of total and direct bilirubin (P < 0.05). These changes were not observed in the LCT group. A significantly better nitrogen balance and a higher ketogenesis from day 3 were observed in the MCT/LCT group. The MCT/LCT group showed a more marked increased utilization of fat than the LCT group, whereas carbohydrate oxidation was less in the MCT/LCT group than in the LCT group (P < 0.05). In children after surgery, MCT/LCT is more protein sparing and induces a better immune response when compared with LCT-containing lipid emulsion. A TPN regimen containing MCT/LCT is likely to result in rapid oxidation of fats for energy without compromising the respiratory system.     

Brain lipid composition in rabbits after total parenteral nutrition with two different lipid emulsions

ObjectiveTo study the changes occurring in brain lipid composition after the administration of total parenteral nutrition (TPN) by comparing two lipid emulsions, one with long-chain triacylglycerols (LCT) and the other with long-chain and medium-chain triacylglycerols (MCT/LCT 50%/50%).MethodsWe used 21 young New Zealand rabbits divided into three groups of seven animals each. Two groups were subjected to TPN for 7 d, with each group receiving using one of two different lipid emulsions: Intralipid 20% (group LCT) and Lipofundin MCT/LCT 20% (group MCT/LCT). The third control group received an oral diet and underwent the same surgical procedure with the administration of intravenous saline solution. The energy administered in the TPN formulas was non-protein 100 kcal ? kg^?1 ? d^?1, with 40% corresponding to fats.ResultsThere were modest increases in plasma cholesterol and triacylglycerols. In the brain tissue, there was a decrease of phosphatidylcholine in animals with TPN, which was greater in group LCT. There were no significant differences in the overall percentage distribution of brain fatty acids among the groups.ConclusionThe lipid emulsions administered in TPN, especially those prepared exclusively with LCT, cause changes in the brain lipid polar fractions of young rabbits.     

Effect of structured lipids as energy substrate after hepatectomy in rats with streptozocin-induced diabetes.

The suitability of energy substrates for use by the remnant liver after 70% hepatectomy was studied in relation to the hepatic energy status in diabetic rats. Rats with streptozocin-induced diabetes underwent 70% hepatectomy and were divided into five groups receiving total parenteral nutrition (TPN) for 24 h. One group received standard TPN without fat, and four groups respectively received standard TPN with long-chain triglycerides (LCTs), medium-chain triglycerides (MCTs), mixed triglycerides (MIX), or structured lipids (SLs) as a 10% lipid emulsion. The latter groups received 60% of nonprotein calories per day with fat emulsion (LCT, MCT, MIX, or SL), and the remaining 40% with glucose. The group that received 100% of nonprotein calories per day with glucose was defined as the TPN group. All rats in the TPN group died from nonketotic hyperosmolarity within 24 h. The blood ketone body ratio (acetoacetate/beta-hydroxybutyrate), the energy charge level of the remnant liver, and the cumulative excretion of 14CO2 in expired breath during 6 h after [14C]glucose administration were all significantly higher in the SL group than in the other groups 24 h after hepatectomy. These findings suggest that SL may be a superior energy substrate to other triglyceride preparations during the immediate posthepatectomy phase in diabetic patients.     

Evaluation of the protein quality of diets containing medium- and long-chain triglyceride in healthy rats

In this study, protein efficiency ratio and net protein utilization together with the kinetic estimates of protein turnover were used to compare the effect of different protein and fat sources in healthy rats. Male Sprague-Dawley CD rats were pair-fed different diets for 14 d. All diets were isonitrogenous and isocaloric, containing 10.4% protein, 10.9-11.4% fat, 31.9-32.8% carbohydrate and 43.5-44.5% moisture (wt/wt). After 14 d of feeding, protein efficiency ratio, net protein utilization, weight gain, intake, fat and protein content in the whole-body and fractional synthetic rates in various tissues were determined. Animals given diets containing medium-chain triglycerides (MCT) demonstrated decreased weight gain and fat content compared to the pair-fed controls receiving long-chain triglycerides (LCT). No difference was seen in protein content, net protein utilization and fractional synthetic rates in the liver and whole body of these MCT-fed rats when compared to those given LCT. Protein efficiency ratios in both of the MCT groups fed MCT + casein and MCT + soy protein were lower than those in the groups given LCT + casein. Although this study did not include a group for LCT and soy protein, these results suggest that MCT reduces the fat deposition without affecting the whole-body protein content. This may have implications for the treatment of obesity. Secondly, the protein efficiency ratio may not be a useful indicator of dietary protein quality when the fat source is MCT.