MPO and fatty liver disease: Using this model, we investigated the changes in the concentrations of serum enzymes (i.e. aspartic transaminase (AST), alanine aminotransferase (ALT), lactic dehydrogenase (LDH), and nitric oxide (NO)) and hepatic cytokines (i.e. malondialdehyde (MDA), superoxide dismutase (SOD), and myeloperoxidase (MPO)) in response to different ischemic preconditioning times and ischemia-reperfusion injury, to explore the optimal time of ischemic preconditioning for the treatment of moderate and severe fatty livers, and the underlying mechanisms.