Silva-Brito Francisca, Magnoni Leonardo J, Fonseca Sthelio Braga, Peixoto Maria João, Castro L Filipe C, Cunha Isabel, de Almeida Ozório Rodrigo Otávio, Magalhães Fernando Antunes, Gonçalves José Fernando Magalhães
CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, University of Porto, Rua dos Bragas n.289, 4050-123, Porto, Portugal.
ICBAS - Instituto de Ciências Biomédicas de Abel Salazar, University of Porto, Porto, Portugal.
Lipids. 2016 Jun;51(6):729-41. doi: 10.1007/s11745-016-4157-6. Epub 2016 May 12.
The meagre (Argyrosomus regius) is taking on increasing importance in the aquaculture industry. In view of the limited supply of fish oil (FO) as a feed ingredient, the study of the capacity to biosynthesize long-chain polyunsaturated fatty acids (LC-PUFA) from alternative dietary oil sources is important. We analyzed changes in fatty acid (FA) desaturase 2 (fads2) and FA elongase 5 (elovl5) mRNA levels in livers and brains in response to FO replacement with a blend of vegetable oils (VO) and selenium (Se) supplementation. Fish were fed for 60 days with either a diet containing FO or a diet including VO, each supplemented or not with organic Se. Results showed that fads2 and elovl5 transcription was higher in liver when fish were fed VO diets. The brain mRNA levels of both genes were not affected by the dietary replacement of FO by VO. FA composition in the liver and skeletal muscle was altered by FO replacement, particularly by decreasing eicosapentaenoic acid and docosahexaenoic acid contents. The α-linolenic, linoleic, and arachidonic acid contents increased in both liver and brain of fish fed VO diets. The effect of Se supplementation on lipid metabolism was evident only in fish fed FO, showing a decrease in the transcription of hepatic fads2. Results indicate that the total replacement of FO by VO in diets modulates the expression of genes involved in LC-PUFA biosynthesis in meagre, affecting the FA profile of the fish flesh.
欧洲舌齿鲈（Argyrosomus regius）在水产养殖业中日益重要。鉴于鱼油（FO）作为饲料成分的供应有限，研究从替代膳食油源生物合成长链多不饱和脂肪酸（LC-PUFA）的能力具有重要意义。我们分析了用植物油（VO）混合物替代FO并补充硒（Se）后，肝脏和大脑中脂肪酸去饱和酶2（fads2）和脂肪酸延长酶5（elovl5）mRNA水平的变化。给鱼喂食含FO的饲料或含VO的饲料60天，每种饲料分别添加或不添加有机硒。结果表明，喂食VO饲料的鱼肝脏中fads2和elovl5的转录水平更高。VO替代FO对这两个基因在大脑中的mRNA水平没有影响。FO替代改变了肝脏和骨骼肌中的脂肪酸组成，特别是降低了二十碳五烯酸和二十二碳六烯酸的含量。喂食VO饲料的鱼肝脏和大脑中的α-亚麻酸、亚油酸和花生四烯酸含量增加。硒补充对脂质代谢的影响仅在喂食FO的鱼中明显，表现为肝脏中fads2转录水平降低。结果表明，饲料中用VO完全替代FO会调节欧洲舌齿鲈中参与LC-PUFA生物合成的基因表达，影响鱼肉的脂肪酸谱。
