Sesame oil as a potential therapeutic agent against nutritional steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent in the general population. Nonalcoholic steatohepatitis (NASH), also called nutritional steatohepatitis and nutritional fibrosing steatohepatitis, can progress to liver failure and hepatocellular carcinoma. Nutritional fibrosing steatohepatitis has been called "a tale of a twohit hypothesis": the "First Hit" is characterized by hepatic injury and fat accumulation, and the "Second Hit" is characterized by hepatic oxidative stress, inflammation, and insulin resistance. Managing NAFLD focuses particularly on diet and exercise; managing NASH focuses on lifestyle modifications, control of associated metabolic issues, and pharmacological therapy for liver injury. Successful care and treatment require an integrative approach. Proposed pharmacological therapies for NASH include vitamin E, ursodeoxycholic acid (a drug used to dissolve gallstones), pioglitazone (one of a class of drugs called thiazolidinediones that are used to treat type 2 diabetes), and metformin (used to treat type 2 diabetes); however, drugs are therapeutically limited and may produce adverse effects. The search for a novel and effective medication to treat nutritional steatohepatitis continues. Sesame oil is nontoxic, antioxidant-rich, and nutritional oil, and it is effective against various diseases models; it attenuates both the first and second hits of nutritional steatohepatitis. Sesame oil attenuates hepatic injury and steatosis, reduces levels of triglycerides, nitric oxide, malondialdehyde (a biomarker of lipid peroxidation), tumor necrosis factor-α, interleukin-6, interleukin-1β, leptin, tissue growth factor-β1, α-smooth muscle actin, fibrosis, and the activity of matrix metalloproteinase-2 and -9, but it increases tissue inhibitor of metalloproteinases-1 and peroxisomal proliferator-activated receptor-γ expression. Thus, we hypothesize that sesame oil would be useful for treating NASH.