Análise de marcadores de estresse oxidativo em amostras biológicas de ratos wistar submetidos a diferentes modelos dietéticos indutores da doença do fígado gorduroso não alcoólica

Abstract

The increased production of reactive oxygen species (ROS) is closely related to the development of nonalcoholic steatohepatitis (NASH). Several experimental models have been used to elucidate the mechanisms involved in the pathogenesis of hepatic steatosis and steatohepatitis. The use of animal models allows a better understanding of their pathophysiology and progression to more advanced stages of the disease. In addition, it allows the study of the mechanisms of action of various therapies available for their treatment. The objective of the present work was to evaluate the oxidative stress in liver extract and blood serum of rats subjected to different dietary patterns, inductor sof the non alcoholic fatty liver disease (NAFLD).The animals (forty male Wistar rats with 21 days) were divided, according to the dietary groups, as: standard (Pad); deficient in choline (DC); deficient in choline and cystine (DCC) and control (Cont). Redox imbalance assays were performed to evaluate liver tissue and blood serum by analysis of lipid peroxidation (TBARS), carbonylated proteins, total thiols, activity of superoxide dismutase, of catalase and DPPH Scavenging Activity, together with histopathological analysis of liver tissues, for comparison of possible oxidative damage. Statistical analysis was performed using the Tukey test, assuming a significance level of 5%.It was observed that the DC and DCC groups had similar behavior in relation to lipid peroxidation, TBARS, presenting higher levels in comparison to Cont and Pad (p <0.001);oxidative damage in proteins presenting similar results as Pad, but higher than Cont (p <0.005).It was observed that the antioxidant defense levels were similar in catalase, SOD and total thiols, with lower results in deficient groups, evidencing an important oxidative damage in animals with DFGNA, regardless of the degree of steatosis.