Inhibitory effect of phytoglycoprotein (24 kDa) on hepatocarcinogenesis in N-nitrosodiethylamine-treated ICR mice

Abstract

Hepatocellular carcinoma (HCC) is becoming one of the most prominent types of cancer in the world. For a long time in Korea Zanthoxylum piperitum DC (ZPDC) has been used in folk medicine to cure several cancers and inflammation. This study was designed to investigate whether ZPDC glycoprotein protected liver tissues against hepatocarcinogenic compounds such as N-nitrosodiethylamine (DEN). To study the chemopreventive effect of ZPDC glycoprotein on hepatocarcinogenesis, ICR mice were injected intraperitoneally with DEN (50 mg/kg) for four weeks. We evaluated the indicators of liver tissue damage (the activity of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT), and thiobarbituric acid-reactive substances (TBARS)), antioxidative enzymes (activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx)), hepatocarcinogenic indicator (heat shock protein (HSP) 70) and hepatocarcinogenic signals (activity of nuclear factor (NF)-κB, cyclooxygenase (COX)-2, and matrix metalloproteinase (MMP)-9) using biochemical methods and immunoblot analysis. The results obtained from this study revealed that ZPDC glycoprotein (20 mg/kg) decreased the levels of LDH, ALT, and TBARS, whereas the activity of SOD and GPx increased in the DEN-treated ICR mice. With respect to the hepatocarcinogenic indicator and hepatocarcinogenic signals, HSP70, NF-κB, COX-2, and MMP-9 activity decreased. The findings suggested that ZPDC glycoprotein prevented damage to liver tissue caused by DEN in the experimental mouse model.