Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common form of liver pathologies and is associated with obesity and the metabolic syndrome. Here, we investigated the molecular mechanisms by which a novel cystine based glutathione precursor with added selenomethionine (F1) prevents hepatic steatosis in a moderate high fat dietary model of NAFLD. Adult (8 weeks old), male apolipoprotein E (ApoE)-/- mice were fed with a normal diet (ND) or high fat diet (HFD), consisting of 21% fat and 0.21% cholesterol, with or without dietary supplementation of F1 (3 g/kg food) for 16 weeks. Compared with ApoE-/- mice fed with ND with or without F1, ApoE-/- mice fed with HFD exhibited significant weight gain, hepatomegaly, and increased serum cholesterol and triglycerides levels with no change in serum albumin levels. High resolution light and electron microscopy revealed micro-and macro-vesicular steatosis in ApoE-/- mice fed on a HFD. HFD-induced obesity also led to increased lipogenesis, oxidative stress, activation of c-Jun-NH(2)-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK), perturbation of the BAX/BCL-2 rheostat, hepatocyte apoptosis, and activation of caspases 9 and 3. F1 fully prevented the adverse effects of HFD on serum triglyceride levels, body and liver weights, and hepatic steatosis and substantially attenuated HFD-induced increase in lipogenesis, oxidative stress, kinase activation, apoptotic signaling, and hepatocyte ultrastructural abnormalities. These results demonstrate that administration of F1, a glutathione precursor, ameliorates HFD-induced hepatic steatosis in ApoE-/- mice and emphasizes the role of oxidative stress in diet-induced obesity and hepatic steatosis.