RESUMO
The current study investigated whether sardine protein mitigates the adverse effects of fructose on plasma glucagonlike peptide-1 (GLP-1) and oxidative stress in rats. Rats were fed casein (C) or sardine protein (S) with or without highfructose (HF) for 2 months. Plasma glucose, insulin, GLP1, lipid and protein oxidation and antioxidant enzymes were assayed. HF rats developed obesity, hyperglycemia, hyperinsulinemia, insulin resistance and oxidative stress despite reduced energy and food intakes. High plasma creatinine and uric acid levels, in addition to albuminuria were observed in the HF groups. The SHF diet reduced plasma glucose, insulin, creatinine, uric acid and homeostasis model assessmentinsulin resistance index levels, however increased GLP1 levels compared with the CHF diet. Hydroperoxides were reduced in the liver, kidney, heart and muscle of SHF fed rats compared with CHF fed rats. A reduction in liver, kidney and heart carbonyls was observed in SHF fed rats compared with CHF fed rats. Reduced levels of nitric oxide (NO) were detected in the liver, kidney and heart of the SHF fed rats compared with CHF fed rats. The S diet compared with the C diet reduced levels of liver hydroperoxides, heart carbonyls and kidney NO. The SHF diet compared with the CHF diet increased the levels of liver and kidney superoxide dismutase, liver and muscle catalase, liver, heart and muscle glutathione peroxidase and liver ascorbic acid. The S diet prevented and reversed insulin resistance and oxidative stress, and may have benefits in patients with metabolic syndrome.