Induction of unscheduled DNA synthesis in gastric mucosa treated in vivo with betel ingredients

Abstract

Induction of unscheduled DNA synthesis (UDS) in the stomach pyloric mucosa of inbred Swiss albino mice and C₃H mice was examined in vitro following administration of various combinations of betel quid ingredients in vivo. Effect of the quid ingredients on replicative DNA synthesis was studied to assess cytotoxicity. Betel leaf, areca nut, lime, tobacco and two popular brands of Indian chewing mixtures induced UDS to a very significant extent. While addition of betel leaf reduces the UDS, tobacco significantly increases it. Study of replicative DNA synthesis revealed that extracts of areca nut, nut with lime and both the brands of commercial chewing mixtures tested induced replicative DNA synthesis. The genotoxic and cytotoxic potential of the test compounds provide quantitative risk factors, especially in the light of their growing use in Asian countries.