Chemopreventive effects of scordinin on diethylnitrosamine and phenobarbital-induced hepatocarcinogenesis in male F344 rats

Modifying effects of scordinin, a biological active component in garlic, on diethylnitrosamine (DEN)- and phenobarbital (PB)-induced hepatocarcinogene sis were examined in rats. Male F344 rats, 5 weeks old, were divided into 8 groups, After a week, groups 1-5 were given DEN (100 mg/kg body weight, i. p.) once a week for 3 weeks, whereas groups 6-8 received vehicle treatment, Group 2 was given 600 ppm scordinin-containing diet in the initiation phas e. From 4 weeks after the start of experiment, groups 3 and 5 were fed scor dinin, and groups 1-3 and 7 received drinking water containing 500 ppm ph, Group 6 was given scordinin diet alone throughout the experiment (24 weeks) , The incidences of hepatocellular adenoma and carcinoma were significantly smaller in group 3 than those in group 1 (P <0.005 and P <0.05, respective ly). The average numbers of liver neoplasms in groups 2 and 3 were signific antly smaller than in group 1 (P <0.01 and P <0.0001, respectively). Glutat hione 5-transferase placental form-positive foci were also significantly de creased by scordinin treatment in the initiation or promotion phase, Scordi nin significantly decreased the mean number of nucleolar organizer regions' protein (AgNORs)/nucleus in hepatocellular adenoma and carcinoma, AgNORs/n ucleus in the non-lesional area was also significantly decreased by scordin in treatment during the promotion phase. These results suggest that scordin in is a promising chemopreventive agent for liver neoplasia.