Location: Obesity and Metabolism Research
Project Number: 2032-51530-022-06-T
Project Type: Trust
Start Date: Dec 1, 2012
End Date: Nov 30, 2014
Consumption of cold water fish, including salmon, has been associated with reductions in cardiovascular health risks. However, the benefits are associated with the fatty acid composition of these fish. Modern fish farming practices result in a change in the composition of oils in farmed vs. wild caught fish. Initial studies indicated that diets prepared from Atlantic salmon raised on a soybean oil rich diet produced insulin resistance in obesity prone mice. In this follow-up study, we will evaluate the mechanisms of insulin resistance and metabolic changes in mice fed diets enriched with protein from salmon raised on fish oil, rapeseed oil, and soybean oil rich diets, with the ultimate goal of guiding the aqua culture industry to produce a product with maximal health benefit.
Fillets of Atlantic salmon fed diets where fish oil was partly (80%) replaced with either rapeseed oil (RO) or soy bean oil (SO) will be used to prepare western diets (WD) for a mouse feeding trial. We will replace 50% of the standard dietary protein source (casein) with proteins from salmon fed FO, RO, or SO (WD-FO, WD-RO and WD-SO, respectively). Due to a large difference in casein and salmon protein digestibility, 50% of the protein in our western-reference diet (WD-Ch) will also be exchanged. A low fat reference group will also be included (LF). Analyses will include: in-depth liver histology; lipidomic profiling of liver and plasma (fatty acids, oxylipins, endocannabioids, and ceramides); pyruvate, glucose, and insulin tolerance tests; fecal bacteria DNA purification, and pyrosequencing (if economically feasible).