K. Karthikeyan et al., Chemopreventive effect of Ocimum sanctum on DMBA-induced hamster buccal pouch carcinogenesis, ORAL ONCOL, 35(1), 1999, pp. 112-119
Ocimum sanctum L., a plant having multi-medicinal properties, has been inve
stigated for its chemopreventive activity against 7,12-dimethylbenz (a) ant
hracene (DMBA)-induced hamster buccal pouch carcinogenesis. O. sanctum, in
the form of fresh leaf paste, aqueous extract and ethanolic extract were to
pically applied and the extracts were orally administered to buccal pouch m
ucosa of animals exposed to 0.5% of DMBA. Incidence of papillomas and squam
ous cell carcinomas were significantly reduced, and increased the survival
rate in the topically applied leaf paste and orally administered extracts t
o animals. Among them, the orally administered aqueous extract showed profo
und effect than the other two forms. Histopathological observations made on
the mucosa confirmed these findings. Further fluorescent spectral studies
at 405 nm excitation on the mucosa of control, DMBA and extracts orally adm
inistered experimental animals showed a prominent maxima at 430 nm for cont
rol, 628 nm for DMBA induced carcinomas while aqueous and ethanolic extract
s administered animals showed at 486 nm and 488 nm, respectively. The fluor
escent intensity at 630 nm (FI630nm) was significantly reduced and the rati
o of fluorescent intensities at 520 nm and 630 nm (FI520nm/630nm) were sign
ificantly increased in orally administered extracts compared to DMBA treate
d animals. These observations suggest that the orally administered extract
of O. sanctum may have the ability to prevent the early events of carcinoge
nesis. (C) 1998 Elsevier Science Ltd. All rights reserved.