Ifremer, UMR 1067, Departement Physiologie Fonctionnelle des Organismes Marins, Technopôle Brest-Iroise, BP 70, 29280 Plouzané, France.
BMC Genomics. 2011 Oct 23;12:522. doi: 10.1186/1471-2164-12-522.
Efforts towards utilisation of diets without fish meal (FM) or fish oil (FO) in finfish aquaculture have been being made for more than two decades. Metabolic responses to substitution of fishery products have been shown to impact growth performance and immune system of fish as well as their subsequent nutritional value, particularly in marine fish species, which exhibit low capacity for biosynthesis of long-chain poly-unsaturated fatty acids (LC-PUFA). The main objective of the present study was to analyse the effects of a plant-based diet on the hepatic transcriptome of European sea bass (Dicentrarchus labrax).
We report the first results obtained using a transcriptomic approach on the liver of two half-sibfamilies of the European sea bass that exhibit similar growth rates when fed a fish-based diet (FD), but significantly different growth rates when fed an all-plant diet (VD). Overall gene expression was analysed using oligo DNA microarrays (GPL9663). Statistical analysis identified 582 unique annotated genes differentially expressed between groups of fish fed the two diets, 199 genes regulated by genetic factors, and 72 genes that exhibited diet-family interactions. The expression of several genes involved in the LC-PUFA and cholesterol biosynthetic pathways was found to be up-regulated in fish fed VD, suggesting a stimulation of the lipogenic pathways. No significant diet-family interaction for the regulation of LC-PUFA biosynthesis pathways could be detected by microarray analysis. This result was in agreement with LC-PUFA profiles, which were found to be similar in the flesh of the two half-sibfamilies. In addition, the combination of our transcriptomic data with an analysis of plasmatic immune parameters revealed a stimulation of complement activity associated with an immunodeficiency in the fish fed VD, and different inflammatory status between the two half-sibfamilies. Biological processes related to protein catabolism, amino acid transaminations, RNA splicing and blood coagulation were also found to be regulated by diet, while the expression of genes involved in protein and ATP synthesis differed between the half-sibfamilies.
Overall, the combined gene expression, compositional and biochemical studies demonstrated a large panel of metabolic and physiological effects induced by total substitution of both FM and FO in the diets of European sea bass and revealed physiological characteristics associated with the two half-sibfamilies.
在水产养殖中，人们已经努力了二十多年，试图开发不含鱼粉（FM）或鱼油（FO）的饲料。已经证明，替代渔业产品的代谢反应会影响鱼类的生长性能和免疫系统及其随后的营养价值，特别是在海洋鱼类中，它们合成长链多不饱和脂肪酸（LC-PUFA）的能力较低。本研究的主要目的是分析植物性饮食对欧洲鲈鱼（Dicentrarchus labrax）肝脏转录组的影响。
我们报告了使用转录组学方法在两个欧洲鲈鱼半同胞家族的肝脏中获得的第一批结果，这些家族在喂食基于鱼类的饮食（FD）时表现出相似的生长速度，但在喂食全植物饮食（VD）时生长速度明显不同。使用寡核苷酸 DNA 微阵列（GPL9663）对整体基因表达进行了分析。统计分析确定了在两组鱼之间差异表达的 582 个独特注释基因，199 个受遗传因素调节的基因和 72 个表现出饮食-家族相互作用的基因。在喂食 VD 的鱼中，发现参与 LC-PUFA 和胆固醇生物合成途径的几个基因的表达上调，表明脂肪生成途径的刺激。通过微阵列分析未检测到 LC-PUFA 生物合成途径调节的饮食-家族相互作用。这一结果与 LC-PUFA 谱一致，在两个半同胞家族的肉中发现 LC-PUFA 谱相似。此外，将我们的转录组数据与血浆免疫参数分析相结合，揭示了在喂食 VD 的鱼中补体活性的刺激与免疫缺陷相关，以及两个半同胞家族之间不同的炎症状态。还发现与蛋白质分解代谢、氨基酸转氨基作用、RNA 剪接和血液凝固相关的生物学过程受到饮食的调节，而参与蛋白质和 ATP 合成的基因的表达在半同胞家族之间存在差异。
总的来说，综合基因表达、组成和生化研究表明，欧洲鲈鱼饲料中完全替代 FM 和 FO 会引起一系列代谢和生理效应，并揭示了与两个半同胞家族相关的生理特征。
