Brown Tyler D, Hori Tiago S, Xue Xi, Ye Chang Lin, Anderson Derek M, Rise Matthew L
Department of Ocean Sciences, Memorial University of Newfoundland, 1 Marine Lab Road, St. John's, NL, A1C 5S7, Canada.
Department of Plant and Animal Sciences, Faculty of Agriculture, Dalhousie University, Truro, NS, Canada, B2N 5E3.
Mar Biotechnol (NY). 2016 Jun;18(3):418-35. doi: 10.1007/s10126-016-9704-x. Epub 2016 Jun 2.
The inclusion of plant meals in diets of farmed Atlantic salmon can elicit inflammatory responses in the distal intestine (DI). For the present work, fish were fed a standard fish meal (FM) diet or a diet with partial replacement of FM with solvent-extracted camelina meal (CM) (8, 16, or 24 % CM inclusion) during a 16-week feeding trial. A significant decrease in growth performance was seen in fish fed all CM inclusion diets (Hixson et al. in Aquacult Nutr 22:615-630, 2016). A 4x44K oligonucleotide microarray experiment was carried out and significance analysis of microarrays (SAM) and rank products (RP) methods were used to identify differentially expressed genes between the DIs of fish fed the 24 % CM diet and those fed the FM diet. Twelve features representing six known transcripts and two unknowns were identified as CM responsive by both SAM and RP. The six known transcripts (including thioredoxin and ependymin), in addition to tgfb, mmp13, and GILT, were studied using qPCR with RNA templates from all four experimental diet groups. All six microarray-identified genes were confirmed to be CM responsive, as was tgfb and mmp13. Histopathological analyses identified signs of inflammation in the DI of salmon fed CM-containing diets, including lamina propria and sub-epithelial mucosa thickening, infiltration of eosinophilic granule cells, increased goblet cells and decreased enterocyte vacuolization. All of these were significantly altered in 24 % CM compared to all other diets, with the latter two also altered in 16 % CM compared with 8 % CM and control diet groups. Significant correlation was seen between histological parameters as well as between five of the qPCR analyzed genes and histological parameters. These molecular biomarkers of inflammation arising from long-term dietary CM exposure will be useful in the development of CM-containing diets that do not have deleterious effects on salmon growth or physiology.
在养殖大西洋鲑的日粮中添加植物性饲料会引发其远端肠道（DI）的炎症反应。在本研究中，在为期16周的饲养试验期间，给鱼投喂标准鱼粉（FM）日粮或用溶剂萃取的亚麻荠粉（CM）部分替代FM的日粮（CM添加量为8%、16%或24%）。在投喂所有含CM日粮的鱼中，生长性能显著下降（希克森等人，《水产养殖营养》，22:615 - 630，2016年）。进行了一项4×44K寡核苷酸微阵列实验，并使用微阵列显著性分析（SAM）和秩乘积（RP）方法来鉴定投喂24%CM日粮的鱼和投喂FM日粮的鱼的远端肠道之间差异表达的基因。通过SAM和RP鉴定出代表6个已知转录本和2个未知转录本的12个特征为CM响应特征。使用来自所有四个实验日粮组的RNA模板，通过qPCR研究了除tgfb、mmp13和GILT之外的6个已知转录本（包括硫氧还蛋白和室管膜蛋白）。微阵列鉴定出的所有6个基因以及tgfb和mmp13均被证实对CM有响应。组织病理学分析确定，在投喂含CM日粮的鲑鱼的远端肠道中存在炎症迹象，包括固有层和上皮下黏膜增厚、嗜酸性粒细胞浸润、杯状细胞增多和肠细胞空泡化减少。与所有其他日粮相比，24%CM组的所有这些变化均显著，与8%CM和对照日粮组相比，16%CM组的后两者也有变化。在组织学参数之间以及qPCR分析的5个基因与组织学参数之间均观察到显著相关性。这些由长期日粮CM暴露引起的炎症分子生物标志物将有助于开发对鲑鱼生长或生理无有害影响的含CM日粮。
