Fontagné Stéphanie, Lataillade Emilie, Brèque Janine, Kaushik Sadasivam
Unit of Nutrition, Aquaculture and Genomics NuAGe, Pôle d'Hydrobiologie INRA, Saint Pée-sur-Nivelle 64310, France.
Br J Nutr. 2008 Jul;100(1):102-11. doi: 10.1017/S0007114507876215. Epub 2007 Dec 6.
The objective of the present study was to characterise some important antioxidant enzymes and their relationships with retinoids and lipid peroxidation during rainbow trout (Oncorhynchus mykiss) early development. Eggs were incubated at 7 degrees C until the swim-up stage whereupon fry were fed two semi-purified diets with 0% (CO) and 8% (OX) oxidised lipid respectively for 2 months at 17 degrees C. The activities and gene expression of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were determined as well as the levels of retinoids, F2-isoprostanes and lipid-soluble fluorescent products (LSFP) at various developmental stages. Only SOD had a detectable activity in embryos which increased during development and was linked with an increase of mitochondrial (SOD2) and cytosolic (SOD1) gene expression. SOD1 and SOD2 mRNA were more abundant in fry fed OX than in fry fed CO. CAT activity and gene expression also increased during development and were higher in fry fed OX compared with fry fed CO. Activity of Se-dependent GPX (Se-GPX) increased during development. The gene expression of cytosolic Se-GPX (GPX1) increased from hatching to 2-month-fed fry. Both phospholipid-hydroperoxide GPX and GPX1 genes were more expressed in fry fed OX than in fry fed CO. Retinoids decreased during development and, by 2 months, were lowered in fry fed OX compared with those fed CO. The levels of LSFP were higher in fry fed OX compared with fry fed CO. The present study demonstrates that antioxidant defence systems are active all through the development of rainbow trout and modulated by feeding oxidised lipid.
本研究的目的是表征虹鳟（Oncorhynchus mykiss）早期发育过程中一些重要的抗氧化酶及其与类视黄醇和脂质过氧化的关系。将鱼卵在7摄氏度下孵化至鱼苗上浮阶段，随后将鱼苗在17摄氏度下分别投喂两种半纯化日粮，日粮中氧化脂质含量分别为0%（CO组）和8%（OX组），持续2个月。测定了超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GPX）的活性及基因表达，以及不同发育阶段类视黄醇、F2-异前列腺素和脂溶性荧光产物（LSFP）的水平。只有SOD在胚胎中有可检测到的活性，其活性在发育过程中增加，并与线粒体（SOD2）和胞质（SOD1）基因表达的增加有关。OX组鱼苗中SOD1和SOD2 mRNA的含量高于CO组鱼苗。CAT活性和基因表达在发育过程中也增加，OX组鱼苗中的CAT活性和基因表达高于CO组鱼苗。硒依赖性GPX（Se-GPX）的活性在发育过程中增加。胞质Se-GPX（GPX1）的基因表达从孵化到2月龄鱼苗期间增加。磷脂氢过氧化物GPX和GPX1基因在OX组鱼苗中的表达均高于CO组鱼苗。类视黄醇在发育过程中减少，到2个月时，OX组鱼苗中的类视黄醇含量低于CO组鱼苗。OX组鱼苗中LSFP的水平高于CO组鱼苗。本研究表明，抗氧化防御系统在虹鳟整个发育过程中均有活性，并受氧化脂质日粮的调节。
