Chemopreventive effects of S-methylcysteine on rat hepatocarcinogenesis induced by concurrent administration of sodium nitrite and morpholine

The aim of the present study was to examine the chemopreventive efficacy of S-methylcysteine (SMC) on rat hepatocarcinogenesis induced by concurrent a dministration of sodium nitrite (NaNO2) and morpholine (Mor) using a medium -term rat liver carcinogenesis bioassay (Ito test). Administration of SMC c aused significant reduction in the areas of glutathione S-transferase place ntal form positive foci along with a significant decrease of hepatocyte 5-b romo-2'-deoxyuridine (BrdU) labeling indices. These results demonstrated po tent chemopreventive effects of SMC against hepatocarcinogenesis due to con current administration of Mor and NaNO2. SMC could thus be an effective che mopreventive agent for decreasing the risk of carcinogenicity from environm ental precursors of N-nitroso compounds. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.