Importance of the relation of the fatty acids ômega-6/ômega-3 in the feeding

• Grant number: 11/18671-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2011
• End date: November 30, 2012
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Science
• Principal Investigator: Monica Roberta Mazalli
• Grantee: Juliana Messias Marques
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated research grant: 09/14656-0 - Importance of the relation of the fatty acids ômega-6/ômega-3 in the feeding, AP.JP

Abstract

The experiment will be carried through in the sector of Experimental of Rabbits young rabbits in growth will be used, for the New race, Zelândia kept in individual cages during the experiment. The biological assay will be executed in a period of 240 days, divided into two phases. Phase 1 will correspond to the 120 days of study, using rabbits submitted to the following diets: hypercholesterolaemic induction (0.5% of cholesterol), disequilibrium in the ratio of Omega-6/ômega-3 (n-6/n-3) of 15:1, and 1:15, respectively, and the ratio of n-6/n-3 of 4:1 (control diet). In the Phase, 16 assays will be formed, which will be divided randomly into 6 groups of 8 rabbits each. Sunflower Oil and flaxseed oil will be used as fatty acid sources of polyunsaturated n-6 and n-3, respectively. Phase 2 will correspond to 120 days of study, sequential to Phase 1 (without interruption). The remaining animals will continue receiving the same diets from Phase 1, except in group B with hypercholesterolaemic induction that will receive beyond this last control treatment to verify the effect. Monthly, it will have a collection of the blood of the rabbits for the total cholesterol determination, LDL and HDL-cholesterol, and triacylglycerol. At the end of Phase 1, four animals of each group will be sacrificed with the removal aorta for posterior determination of lipids plates and oxidated LDL-cholesterol. Dosage of TBARS (Thiobarbituric Acid-Reactive Substances) will be used as an index of oxidation of LDL cholesterol. At the end of the experiment after 240 days, all the rabbits will be abated and their aortas will be removed for more planimetric determination of lipids plates, index of oxidation of the LDL-cholesterol, and verification of the supply of the control diet (ratio of n-6/n-3 of 4:1) will go to interrupt or inhibit the atherosclerotic injuries. Also will be developed methodology "in vitro" to evaluate the best relation of fatty acid n-6/ n-3 in the prevention of the development of atherosclerosis and the implications of these fatty acids in the endothelial, hepatic, and adipose cells. Moreover, the activity of proteins and the expression of genes will be investigated involved in the etiology of atherosclerosis.(AU)