Promotion Potential of Madder Color in a Medium-Term Multi-Organ Carcinogenesis Bioassay Model in F344 Rats
A medium-term multi-organ carcinogenesis bioassay in rats was conducted to assess any possible tumor promoting effects of madder color extracted from the root of madder. Male F344 rats were divided into 5 groups of 20 each. All rats of groups 1 to 4 were given DMD treatment, consisted of multicarcinogens, N-nitrosodiethylamine (DEN), N-methyl-N-nitrosourea (MNU), and N-bis (2-hydroxypropyl) nitrosamine (DHPN), for 4 wk, while group 5 served as untreated control without carcinogens. The animals were then administered a basal diet containing madder color at doses of 5.0% (group 1), 2.5% (group 2 with 0.75% additional dextrin), or 0 (groups 3 with 1.5% additional dextrin, 4 without dextrin and 5) for the following 28 wk (total 32 wk). The total amount of dextrin in groups 1 to 3 diets was adjusted to 1.5% by extra dextrin because madder color powder contained dextrin. Key organs were observed histopathologically and glutathione S-transferase placental form (GST-P) positive foci of the liver were quantified. In the liver, 5.0% and 2.5% treated groups showed statistically significant dose-related increases in both number and area of GST-P positive foci, number: 2.81 ± 0.90 and 1.96 ± 0.93 (groups 1 and 2), area: 0.99 ± 2.49 and 0.37 ± 0.77, as compared with control, number: 0.87 ± 0.72, area: 0.06 ± 0.06 (group 3). In the kidneys, incidences (and numbers) of adenoma treated with 5.0% and 2.5%, 47.4% (0.20 ± 0.24), and 47.4% (0.13 ± 0.15) (groups 1 and 2) were significantly increased compared to control, 0% (0) (group 3). In conclusion, madder color demonstrated significant tumor promoting effects in the liver and kidneys in the DMD model.
Document Type: Research Article
Affiliations: Authors are with Onco-Pathology, Dept. of Pathology and Host-Defence, Faculty of Medicine, Kagawa Univ., 1750-1 Ikenobe, Kagawa 761-0793, Japan. Direct inquiries to author Imaida ( )., Email: [email protected]
Publication date: April 1, 2008