AbstractThe nonalcoholic fatty liver disease (NAFLD) and the nonalcoholic steatohepatitis (NASH) are crescent causes for hepatic disease, becoming a concern in Public Health. The model of rat induction of fatty liver disease through a diet rich in fructose has its effectiveness described by specialyzed litterature. Controversial are the effects of polyunsaturated omega-3 fatty acids, specially in relation to the adequate quantity for the treatment of these diseases. Being so, this work will try to elucidate part of the lipidic metabolism, specially in formation of hepatic triglycerides (TG), composition of tissue fatty acids and formation of HDL in rats with NAFLD induced by fructose, and verify the alterations provoked by consumption of n-3 in different proportions. The work will be constituted of 3 phases, at the first will be formed two groups with Wistar male rats, initially weighing about 250g. During 60 days both groups will receive the AIN-93 diet. The first one (Control Group - CG) will receive water and will be constituted of 20 rats. The second one will receive water with 30% of fructose and will be formed by 80 rats. Past the initial 60 days, 50 rats, 40 from FrG and 10 from CG, will be for 30 more days under the same experimental conditions. At the end of this period, after 12hs of fasting, it will be administered by gavage 10 or 8 or 6mg of fish oil (FO) for the groups FO10G, FO8G and FO6G, respectively. The control group phase I (CGPI) and the fructose phase I (GFrFI) will receive 10mg of water. These animals will be sacrificed 3 hours after the gavage. The other 50 rats, past the initial 60 days, will receive diets with different quantities of FO during 30 days: one group will receive 7% of diet as FO (FO7G); other one will receive 5% of FO (FO5G) and 2% of soybean oil (SO); and the third one will receive 2% of FO (FO2G) and 5% of SO. There will be a group from FrG that will receive diet with 7% of SO. These groups will keep with 30% of fructose in the water. A group from CG will receive AIN-93 diet and water. The animals will be sacrificed after 10 hours of fasting. The weight of the animals and of the consumed diet will be weekly assessed. After the sacrifice, will be collected liver, blood, epididymal fat, perirenal, mesenteric and subcutanea fraction for biochemical determinations. Further analysis will be made with the purpose of elucidating some steps of lipidic metabolism in NAFLD, considering the role of oxidative stress and of insulin resistence, expression of TG-foming enzymes and hepatic receptors.Keywords: nonalcoholic fatty liver disease, polyunsaturated omega-3 fatty acids; fructose; rats; fatty acids; MGAT; DGAT.
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