Biomaterial Database

Inhibitory effect of caffeic acid esters on azoxymethane-induced biochemical changes and aberrant crypt foci formation in rat colon. 1993

C V Rao, and D Desai, and B Simi, and N Kulkarni, and S Amin, and B S Reddy

Division of Nutritional Carcinogenesis, American Health Foundation, Valhalla, New York 10595.

Previous work from this laboratory established that caffeic acid esters, present in the propolis of honey bee hives, are potent inhibitors of human colon tumor cell growth, suggesting that these compounds may possess antitumor activity against colon carcinogenesis. The present study was designed to investigate (a) the inhibitory effects of methyl caffeate (MC) and phenylethyl caffeate (PEC) on azoxymethane (AOM)-induced ornithine decarboxylase (ODC), tyrosine protein kinase (TPK), and arachidonic acid metabolism in liver and colonic mucosa of male F344 rats, (b) the effects of caffeic acid, MC, PEC, phenylethyl-3-methylcaffeate (PEMC), and phenylethyl dimethylcaffeate (PEDMC) on in vitro arachidonic acid metabolism in liver and colonic mucosa, and (c) the effects of PEC, PEMC, and PEDMC on AOM-induced aberrant crypt foci (ACF) formation in the colon of F344 rats. At 5 weeks of age, groups of animals were fed diets containing 600 ppm MC or PEC (biochemical study) or 500 ppm PEC, PEMC, or PEDMC (ACF study). Two weeks later, all animals except the vehicle-treated groups were given s.c. injections of AOM, once weekly for 2 weeks. The animals intended for the biochemical study were sacrificed 5 days later and colonic mucosa and liver were analyzed for ODC, TPK, lipoxygenase, and cyclooxygenase metabolites. The animals intended for the ACF study were sacrificed 9 weeks later and analyzed for ACF in the colon. The results indicate that the PEC diet significantly inhibited AOM-induced ODC (P < 0.05) and TPK (P < 0.001) activities in liver and colon. The PEC diet significantly (P < 0.001) suppressed the AOM-induced lipoxygenase metabolites 8(S)- and 12(S)-hydroxyeicosatetraenoic acid (HETE). The animals fed the MC diet exhibited a moderate inhibitory effect on ODC and 5(S)-, 8(S)-, 12(S)-, and 15(S)-HETEs and a significant (P < 0.001) effect on colonic TPK activity. However, the MC and PEC diets showed no significant inhibitory effects on cyclooxygenase metabolism. In an in vitro study, caffeic acid and MC showed inhibitory effects on HETE formation only at a 100 microM concentration, whereas PEC, PEMC, and PEDMC suppressed in vitro HETE formation in a dose-dependent manner. AOM-induced colonic ACF were significantly inhibited in the animals fed PEC (55%), PEMC (82%), or PEDMC (81%). The results of the present study indicate that PEC, PEMC, and PEDMC, present in honey, inhibit AOM-induced colonic preneoplastic lesions, ODC, TPK, and lipoxygenase activity, which are relevant to colon carcinogenesis.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009955	Ornithine Decarboxylase	A pyridoxal-phosphate protein, believed to be the rate-limiting compound in the biosynthesis of polyamines. It catalyzes the decarboxylation of ornithine to form putrescine, which is then linked to a propylamine moiety of decarboxylated S-adenosylmethionine to form spermidine.	Ornithine Carboxy-lyase,Carboxy-lyase, Ornithine,Decarboxylase, Ornithine,Ornithine Carboxy lyase
D011230	Precancerous Conditions	Pathological conditions that tend eventually to become malignant.	Preneoplastic Conditions,Condition, Preneoplastic,Conditions, Preneoplastic,Preneoplastic Condition,Condition, Precancerous,Conditions, Precancerous,Precancerous Condition
D011505	Protein-Tyrosine Kinases	Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.	Tyrosine Protein Kinase,Tyrosine-Specific Protein Kinase,Protein-Tyrosine Kinase,Tyrosine Kinase,Tyrosine Protein Kinases,Tyrosine-Specific Protein Kinases,Tyrosylprotein Kinase,Kinase, Protein-Tyrosine,Kinase, Tyrosine,Kinase, Tyrosine Protein,Kinase, Tyrosine-Specific Protein,Kinase, Tyrosylprotein,Kinases, Protein-Tyrosine,Kinases, Tyrosine Protein,Kinases, Tyrosine-Specific Protein,Protein Kinase, Tyrosine-Specific,Protein Kinases, Tyrosine,Protein Kinases, Tyrosine-Specific,Protein Tyrosine Kinase,Protein Tyrosine Kinases,Tyrosine Specific Protein Kinase,Tyrosine Specific Protein Kinases
D011916	Rats, Inbred F344	An inbred strain of rat that is used for general BIOMEDICAL RESEARCH purposes.	Fischer Rats,Rats, Inbred CDF,Rats, Inbred Fischer 344,Rats, F344,Rats, Inbred Fisher 344,CDF Rat, Inbred,CDF Rats, Inbred,F344 Rat,F344 Rat, Inbred,F344 Rats,F344 Rats, Inbred,Inbred CDF Rat,Inbred CDF Rats,Inbred F344 Rat,Inbred F344 Rats,Rat, F344,Rat, Inbred CDF,Rat, Inbred F344,Rats, Fischer
D002109	Caffeic Acids	A class of phenolic acids related to chlorogenic acid, p-coumaric acid, vanillic acid, etc., which are found in plant tissues. It is involved in plant growth regulation.	Acids, Caffeic
D003106	Colon	The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.	Appendix Epiploica,Taenia Coli,Omental Appendices,Omental Appendix,Appendices, Omental,Appendix, Omental
D003110	Colonic Neoplasms	Tumors or cancer of the COLON.	Cancer of Colon,Colon Adenocarcinoma,Colon Cancer,Cancer of the Colon,Colon Neoplasms,Colonic Cancer,Neoplasms, Colonic,Adenocarcinoma, Colon,Adenocarcinomas, Colon,Cancer, Colon,Cancer, Colonic,Cancers, Colon,Cancers, Colonic,Colon Adenocarcinomas,Colon Cancers,Colon Neoplasm,Colonic Cancers,Colonic Neoplasm,Neoplasm, Colon,Neoplasm, Colonic,Neoplasms, Colon
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001397	Azoxymethane	A potent carcinogen and neurotoxic compound. It is particularly effective in inducing colon carcinomas.