Serum ornithine carbamyltransferase reflects hepatic damage in diabetic obese mice

Abstract

As ornithine carbamyltransferase (OCT) has proved to be a sensitive serum marker in the detection of hepatotoxicity in several models, it is important to confirm its application to the diagnosis of non-alcoholic fatty liver disease. C57BL/6, KK-Ta and KK-Ay mice were fed a high-fat diet for 8 weeks and serum enzyme markers were examined. Serum OCT and alanine aminotransferase (ALT) were also measured in diabetic obese ob/ob and db/db mice fed a normal diet. Liver damage in these mice was evaluated by the hepatic content of tumor necrosis factor-alpha. Serum levels of OCT increased in KK-Ay fed a high-fat diet compared with the normal diet-fed group, whereas C57BL/6 and KK-Ta mice were not affected. In ob/ob mice, the relative increase was always greater in OCT than in ALT. In contrast, in db/db mice, the relative increase was always greater in ALT. Hepatic tumor necrosis factor-alpha was significantly elevated in ob/ob mice, but not in db/db mice. Serum OCT seemed to reflect tumor necrosis factor-alpha-mediated hepatic damage when compared with ALT in diabetic obese mice and could be useful in the application for non-alcoholic fatty liver disease with features of metabolic syndrome, such as obesity and diabetes.