Modifying effects of Terminalia catappa on azoxymethane-induced colon carcinogenesis in male F344 rats.
The modifying effects of dietary administration of an herb, Terminalia catappa (TC), were investigated on rat colon carcinogenesis induced by a carcinogen azoxymethane (AOM). The number of aberrant crypt foci (ACF) and beta-catenin accumulated crypts (BCACs) in the colon, and proliferating cell nuclear antigen (PCNA) labelling index in the colonic epithelium were examined in a total of 36 male F344 rats. All animals were randomly divided into five experimental groups (4-10 rats in each group). At 6 weeks of age, rats in groups 1, 2 and 3 were given s.c. injections of AOM once a week for 2 weeks at a concentration of 20 mg/kg body weight. One week before the first injection of AOM, rats in groups 2 and 3 were fed a diet containing 0.02 and 0.1% TC, respectively, throughout the experiment. Rats in group 4 were fed a diet containing 0.1% TC. Rats in group 5 were served as untreated controls. All animals were sacrificed at the experimental week 5 after the start of the experiment. Oral administration of TC at both doses significantly decreased the numbers of both ACF/colon/rat (P<0.05 for 0.02% TC, P<0.005 for 0.1% TC) and BCAC/cm/rat (P<0.05 for both 0.02 and 0.1% TC), when compared with the control group (group 1). Colonic PCNA labelling index in groups 2 and 3 was also significantly lower than that in group 1 (P<0.001 for 0.02% TC, P<0.005 for 0.1% TC). These results suggest that TC has a potent short-term chemopreventive effect on biomarkers of colon carcinogenesis and this effect may be associated with the inhibition of the development of ACF and BCACs.
Morioka
T
T
Tumor Pathology, University of the Ryukyus Faculty of Medicine, 207 Uehara Nishihara-cho, Okinawa 903-0215, Japan.
Suzui
M
M
Nabandith
V
V
Inamine
M
M
Aniya
Y
Y
Nakayama
T
T
Ichiba
T
T
Yoshimi
N
N
D000284:Administration, Oral; D000818:Animals; D001397:Azoxymethane / Q000008:administration & dosage / Q000633:toxicity; D014408:Biomarkers, Tumor / Q000097:blood*; D002273:Carcinogens / Q000008:administration & dosage / Q000633:toxicity; D002471:Cell Transformation, Neoplastic; D018890:Chemoprevention; D003108:Colonic Diseases / Q000139:chemically induced / Q000517:prevention & control / Q000662:veterinary; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000517:prevention & control* / Q000662:veterinary; D008297:Male; D008517:Phytotherapy / Q000662:veterinary; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D018809:Proliferating Cell Nuclear Antigen / Q000097:blood; D011897:Random Allocation; D051381:Rats; D011916:Rats, Inbred F344; D029766:Terminalia / Q000737:chemistry*
D014408:Biomarkers, Tumor; D002273:Carcinogens; D010936:Plant Extracts; D018809:Proliferating Cell Nuclear Antigen; D001397:Azoxymethane