NA - Effects of fish oils/proteins and contaminants on obesity-linked insulin resistance

Insulin resistance (i.e. where a given concentration of insulin does not show the expected magnitude of effects on target cells) is a hallmark of Type 2 diabetes and obesity, two metabolic diseases reaching today epidemic proportions. Both the amount and type of nutrients (fat, carbohydrate or protein) influence insulin action. For instance, diets rich in saturated fats or rich in n-6 fatty acid (FA) lead to insulin resistance. Substitution with n-3 long-chain FAs (e.g. fish oil) or fish proteins may pre vent diet-induced insulin resistance. Furthermore, common contaminants present in nutrients may affect insulin action. In the present project, we want to test the effect of supplementing n-3 FAs and/or fish proteins in a high-fat/sucrose diet on whole-bo dy and tissue insulin resistance. The influence of n-3 FAs on insulin sensitivity will also be studied in a new genetic model in which the expression of the Fat-1 gene able to convert n-6 to n-3 FAs. In addition, we want to investigate interactions betwee n nutrients and common contaminants in seafood on insulin sensitivity. The aims of this project are to clarify the mechanisms by which n-3 FAs and/or fish proteins can prevent the development of diet-induced insulin resistance and to contribute to develop novel nutritional approaches for the prevention of type 2 diabetes. Furthermore, we will establish whether contaminants may affect insulin sensitivity and clarify their potential role in the development of type 2 diabetes or obesity.