Suplementação de ácidos graxos poli-insaturados ômega-3 reduz marcadores inflamatórios e melhora a ação da insulina em fígado de camundongos

Abstract

Objective: The aim of the present study was to assess the effects of omega-3 polyunsaturated fatty acid supplementation on insulin signaling and the pro-inflammatory pathway in the liver tissue of mice. Methods: Swiss mice were divided into six groups given different dosages of fish oil containing omega-3 (1mg, 5mg, 10mg and 50mg) by gavage. The control group was given water. Fasting plasma glucose was measured on days 0 (no supplementation), 14 and 21 (after supplementation) to determine the dosage and time-dependent effects of omega-3. Because the group n-3-21days (21 days of omega-3 supplementation) demonstrated lower blood glucose, this time interval was selected for molecular analysis. After an 8-hour fast, liver tissue samples were taken from the control and n-3-21days groups, and western blot analyses were performed to assess insulin signaling and the pro-inflammatory pathway. Results: The results showed that the dosage of 1Omg leads to greater reduction in blood glucose at 14 and 21 days when compared with other dosages. Thus, this dosage was selected for molecular analysis. This dosage significantly decreased phosphorylation of c-Jun N-terminal protein kinase and lkB kinase and protein levels of nuclear factor Kappa-light-chain-enhancer of activated B cells. In parallel, increased insulin pathway signaling was observed, as confirmed by increases in insulin receptors, insulin receptor substrate 1 and protein kinase B phosphorylation. Conclusion: The present study suggests that omega-3 fatty acids improve insulin signaling by reducing inflammation. These results may be one of the explanations for low fasting glucose.