title: Rat medium-term multi-organ carcinogenesis bioassay of Agaricus blazei Murrill fruit-body extract.
abstract: The modifying potential of Agaricus blazei Murrill fruit-body extract (ABFE) on tumor development was investigated in a medium-term multi-organ carcinogenesis bioassay. Male 6-week-old F344 rats were treated with N-nitrosodiethylamine (DEN), N-methyl-N-nitrosourea (MNU), 1,2-dimethylhydrazine dihydrochloride (DMH), N-butyl-N-(hydroxybutyl)-nitrosamine (BBN), and diisopropanolnitrosamine (DHPN) for initiation (DMBDD treatment). After a 1-week withdrawal period, the animals received distilled water (vehicle control) or ABFE A, gamma-amino butyric acid (GABA) at 0.8 mg/kg, ABFE B (GABA level of 3.0mg/kg) or ABFE C (GABA level of 12.0mg/kg) by gavage for 24 weeks. There were no effects of ABFE on survival rate, general condition, body weight, food and water consumption, and organ weights. The multiplicity of large intestinal nodules, smaller than 2mm was significantly increased in the ABFE C group with DMBDD treatment. However, there were no significantly inter-group differences in incidences of hyperplastic or neoplastic lesions in colon or other organs, or in immunohistochemically identified preneoplastic lesions in the liver. In conclusion, A. blazei Murrill fruit-body extract, even at a GABA level up to 12 mg/kg, did not exert modifying potential in the present medium-term multi-organ carcinogenesis bioassay in male F344 rats (DMBDD method).
authors.affiliation: DIMS Institute of Medical Science, Inc, 64 Goura, Nishiazai, Azai-cho, Ichinomiya 491-0113, Japan. doidoi@dims.co.jp
authors.forename: Yuko
authors.initials: Y
authors.lastname: Doi
authors.forename: Fumio
authors.initials: F
authors.lastname: Furukawa
authors.forename: Mayuko
authors.initials: M
authors.lastname: Suguro
authors.forename: Hikaru
authors.initials: H
authors.lastname: Ito
authors.forename: Norio
authors.initials: N
authors.lastname: Imai
authors.forename: Kyoko
authors.initials: K
authors.lastname: Nabae
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Toda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Inatomi
authors.forename: Satomi
authors.initials: S
authors.lastname: Kinugasa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kobayashi
mesh_terms: D000364:Agaricus / Q000737:chemistry*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002273:Carcinogens / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D004326:Drinking / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D005260:Female; D048690:Fruiting Bodies, Fungal / Q000737:chemistry*; D005982:Glutathione Transferase / Q000378:metabolism; D006965:Hyperplasia / Q000139:chemically induced / Q000473:pathology; D007150:Immunohistochemistry; D008297:Male; D009369:Neoplasms / Q000139:chemically induced / Q000473:pathology; D009929:Organ Size / Q000187:drug effects; D011230:Precancerous Conditions / Q000139:chemically induced / Q000473:pathology; D051381:Rats; D011916:Rats, Inbred F344; D016019:Survival Analysis; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
chemical_list: D002273:Carcinogens; D005680:gamma-Aminobutyric Acid; D005982:Glutathione Transferase