title: Comparative potencies of nutraceuticals in chemically induced skin tumor prevention.
abstract: Four nutraceuticals, sugar beet roots, cucumber fruits, New Zealand spinach leaves, and turmeric rhizomes, were evaluated for their comparative effectiveness against dimethylbenz[a]anthracene (DMBA)-initiated and croton oil-promoted skin tumors. Three different protocols were used. The most effective protocol (Protocol 2) is the topical application of the nutraceuticals 1 h before croton oil. There was a decrease in the percent skin tumor incidence, a decrease in multiplicity of skin tumors, and a later onset of skin tumors compared with the positive control for all the nutraceuticals tested, with turmeric being the most potent, as evidenced by 30% skin tumor incidence, 87.2% decrease in skin tumors, and a 5-wk delay in skin tumor formation compared with the positive control. Topical application of the nutraceuticals daily for 5 days before DMBA and 1 h before croton oil (Protocol 1) and immediately after croton oil (Protocol 3) did not have an additional protective effect against skin tumors compared with Protocol 2. Kruskal-Wallis analysis of variance by ranks showed that Protocol 2 is the most effective, with the treatment groups belonging to different populations at the 0.05 level of significance compared with alpha = 0.20 for Protocols 1 and 3. Turmeric is the most potent nutraceutical, because the average number of tumors formed after application of tumeric is statistically different from the positive control at alpha = 0.01.
authors.affiliation: Natural Products Research Laboratory, Institute of Chemistry, University of the Philippines, Diliman, Quezon City 1101, Philippines.
authors.forename: Irene M
authors.initials: IM
authors.lastname: Villaseñor
authors.forename: Ma Karenina B
authors.initials: MK
authors.lastname: Simon
authors.forename: Ainstein M A
authors.initials: AM
authors.lastname: Villanueva
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene / Q000633:toxicity; D000287:Administration, Topical; D000818:Animals; D027461:Beta vulgaris; D003436:Croton Oil / Q000633:toxicity; D018553:Cucumis sativus; D030024:Curcuma; D015994:Incidence; D051379:Mice; D010936:Plant Extracts / Q000008:administration & dosage*; D011897:Random Allocation; D012878:Skin Neoplasms / Q000139:chemically induced / Q000453:epidemiology / Q000517:prevention & control*; D018724:Spinacia oleracea
chemical_list: D010936:Plant Extracts; D015127:9,10-Dimethyl-1,2-benzanthracene; D003436:Croton Oil