Hepatic triacylglycerol secretion, lipid transport and tissue lipid uptake in blunt snout bream (Megalobrama amblycephala) fed high-fat diet
Hepatic triacylglycerol secretion, lipid transport and tissue lipid uptake in blunt snout bream (Megalobrama amblycephala) fed high-fat diet
复制标题
高脂饲料喂养的团头鲂的肝脏三酰甘油分泌、脂质转运和组织脂质摄取
DOI：
10.1016/j.aquaculture.2013.06.003
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发表时间：
2013-09-15
期刊：
影响因子：
4.5
通讯作者：
Zhang, Chun-Nuan
中科院分区：
文献类型：
--
作者：
Lu, Kang-Le;Xu, Wei-Na;Zhang, Chun-Nuan
高脂饲料可能对生长有有利的影响，部分基于蛋白质节约，但高脂饲料往往会导致一些鱼类肝脏中过量的脂肪沉积。因此，本研究的目的是研究富含脂肪的饮食对肝脏脂肪沉积机制的影响。300头团头鲂幼鱼（初始体重18.00 ± 0.05g）用两种饲料（5%和15%脂肪）饲养8周。组织学和生化参数进行了测定。腹腔注射泊洛沙姆407（脂蛋白脂酶抑制剂）测定肝三酰甘油（TG）分泌率。通过测定脂蛋白组分研究脂质转运。我们还通过测定组织中脂蛋白脂酶（LPL）活性和mRNA表达来检查脂质摄取。我们的研究结果表明，在摄入高脂饮食后，肝细胞器的超微结构发生病变。高脂饲料组的肝脏TG分泌率和血浆极低密度脂蛋白（VLDL）含量显著低于对照组。同时，脂蛋白组分的变化也很明显。在肝脏、肌肉和肠系膜脂肪组织中，高脂组多不饱和脂肪酸（PUFA）含量显著增加，饱和脂肪酸（SFA）和单不饱和脂肪酸（MUFA）含量显著降低。LPL的活性和mRNA表达也在这些组织中增加。总体而言，肝脏外的脂质转运水平较低，脂质转运的改变和脂质摄取的增加是导致团头鲂脂肪肝的原因。(C)2013爱思唯尔有限公司版权所有。
High-fat diets may have favorable effects on growth partly based on protein-sparing, but high-fat diets often lead to excessive fat deposition in the liver of some fish. The goal of the study was therefore to investigate effects of fat-rich diet on mechanisms involved in fat deposition in the liver. Three hundred blunt snout bream (Megalobrama amblycephala) juveniles (initial weight 18.00 +/- 0.05 g) were fed with two diets (5% or 15% fat) for 8 weeks. Histological and biochemical parameters were determined. The hepatic triacylglycerol (TG) secretion rate was measured by intraperitoneal injection with poloxamer 407 (a lipoprotein lipase inhibitor). Lipid transport was studied by determining components of lipoproteins. We also examined lipid uptake by assaying lipoprotein lipase (LPL) activities and mRNA expressions in tissues. Our results showed that ultrastructural lesions of organelles in hepatocytes occurred after intake of a high-fat diet. The hepatic TG secretion rate and plasma very low density lipoprotein (VLDL) amount of fish fed high-fat diet were significantly lower compared to those of fish fed control diet. Concomitantly, variations of components of lipoproteins were also apparent. In the liver, muscle and mesenteric fat tissue, the percentage of polyunsaturated fatty acid (PUFA) was significantly increased, while both saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) percentages decreased in high-fat group. Both activities and mRNA expressions of LPL were also increased in these tissues. On the whole, a low level of lipid transport out of the liver, alterations of lipid transport and elevated lipid uptake contributed to fatty liver of blunt snout bream fed high-fat diet. (C) 2013 Elsevier B.V. All rights reserved.