Preventive effect of thiacremonone on the hepatocarcinogenesis initiated by N-nitrosodiethylamine in rats

The present study was carried out to examine the chemopreventive effects of thiacremonone, which is found in heated garlic, on the formation of the preneoplastic foci and glutathione-dependent detoxifying enzyme activities in rat hepatocarcinogenesis. F344 rats were given an intraperitoneal injection of N-nitrosodiethylamine (DEN) at a dose of 200 mg/kg body weight and were then administered a gavage of thiacremonone 2 weeks after initiating the DEN treatment. All animal were subjected to a 2/3 partial hepatectomy at 3 weeks after DEN initiation. The numbers and the placental glutathione S-transferase positive (GSTP+) foci in the thiacremonone-treated groups decreased significantly compared with those in the DEN alone group. Thiobarbituric acid reactive substances content in the thiacremonone treated group (10 mg/kg) decreased significantly compared with that in the DEN alone. These results suggest that thiacremonone may have potential chemopreventive effects on rat hepatocarcinogenesis induced by DEN.