Nutrigenomic profiling of transcriptional processes affected in liver and distal intestine in response to a soybean meal-induced nutritional stress in Atlantic salmon (Salmo salar), Comparative Biochemistry and Physiology

(2015) Nutrigenomic profiling of transcriptional processes affected in liver and distal intestine in response to a soybean meal-induced nutritional stress in Atlantic salmon (Salmo salar), Comparative Biochemistry and Physiology-Part D: Genomics and Proteomics, 15, pp. 1-11. Abstract 17 The aim of the present study was to generate an experimental model to characterize the 18 nutrigenomic profile of a plant-derived nutritional stress. Atlantic salmon (Salmo salar) was 19 used as the model species. The nutritional stress was induced by inclusion of dietary defatted 20 soybean meal (SBM), as this ingredient had been previously demonstrated to induce 21 enteropathy in the distal intestine and reduce growth in salmon. Triplicate groups of Atlantic 22 salmon were fed increasing concentrations (0, 100, 200 and 300 g kg-1) of SBM for 12 weeks 23 and reduced growth performance was used as the indicator of nutritional stress. The 24 transcriptome was analysed in two tissues, liver and distal intestine, with the hypothesis being 25 that the liver transcriptome would be characterized by gene expression responses related to 26 overall growth and health performance, whereas intestinal gene expression would be 27 dominated by specific responses to SBM. A set of 133 genes was differentially expressed in 28 liver including 44 genes in common with the intestinal response. The liver specific response 29 included up-regulation of genes involved in protein digestion, energy metabolism and 30 immune functions, whereas genes regulated in other metabolic pathways were generally 31 anabolic and down-regulated. These responses may be more related to general nutritional 32 stress than to SBM per se. The transcriptomic profile in the distal intestine was consistent 33 with the enteritis response as described previously. This study provides a comprehensive 34 report on the profiles of liver and distal intestine transcriptomes, highlighting the role of the 35 former tissue in fish undergoing SBM-induced nutritional stress.