Oral Copaiba Oil-Resin Supplementation Reduces Plasma and Hepatic Oxidative Stress in Female and Male Hypothalamic-Obese Animals.

Oxidative stress is a characteristic of obesity dysfunction-associated fatty liver disease. Copaiba oil-resin (Co-resin) is known for its antioxidant and hepatoprotective properties; however, its effects on the oxidative system of obese rodents are unknown, particularly with regard to potential sex differences. Here, we evaluated the effects of the oral Co-resin supplementation on plasma and hepatic oxidative parameters in male and female rodents with hypothalamic-induced obesity. Hypothalamic obesity was induced during the early postnatal days (PND) by monosodium glutamate (MSG; 4 g kg-1) administration, while control (CON) animals received equimolar saline solution. From 30 to 90 PND, MSG, and CON groups (both sexes) were divided into Co-resin-supplemented (0.5 mL kg-1, three times a week/8 weeks) or non-supplemented animals. Adiposity, plasma, and hepatic metabolic and oxidative markers were assessed. Hepatic tissue was used for histological analysis. Male and female MSG-obese rats presented higher adiposity and metabolic dysfunction, associated with reductions in plasma and hepatic antioxidative activities of glutathione reductase, glutathione-S-transferase, and catalase. Reduced hepatic glutathione peroxidase was also observed in MSG-obese rats of both sexes. Moreover, plasma, and hepatic thiobarbituric acid reactive substances and reactive species were increased in MSG-obese (male and female) animals. MSG-obese rats of both sexes displayed abnormal hepatic histopathology and reduced liver superoxide dismutase and catalase contents. Co-resin oral supplementation effectively restored plasma and hepatic oxidative systems in MSG-obese males and females without significantly adiposity change. However Co-resin supplementation had more positive effects on the metabolic parameters of MSG-obese females, since it restored liver structural abnormalities, plasma triglyceride levels, and insulin responsiveness.