title: Antitumorigenic effect of a mammalian lignan precursor from flaxseed.
abstract: Secoisolariciresinol diglycoside (SD), a mammalian lignan precursor found in high-fiber foods, was isolated from flaxseed and tested for effects on mammary tumorigenesis in rats fed a high-fat (20%) diet. Ingestion of purified SD at 1.5 mg/day for 20 weeks starting 1 week after treatment with the carcinogen dimethylbenzanthracene resulted in a 37% reduction (p < 0.05) in the number of tumors per tumor-bearing rat and a 46% reduction (p < 0.05) in the number of tumors per tumor-bearing rat and a 46% reduction (p < 0.05) in the number of tumors per number of rats in each group. Urinary mammalian lignan excretion significantly increased (p < 0.0001) with SD treatment, indicating the conversion of SD to mammalian lignans. No enlargement or gross abnormalities of the major organs were observed in the SD-treated rats. This study showed, for the first time, that SD has an antitumor effect when provided at the early promotion stage of tumorigenesis and may contribute to the health benefits of high-fiber foods.
authors.affiliation: Department of Nutritional Science, Faculty of Medicine, University of Toronto, Ont, Canada.
authors.forename: L U
authors.initials: LU
authors.lastname: Thompson
authors.forename: M M
authors.initials: MM
authors.lastname: Seidl
authors.forename: S E
authors.initials: SE
authors.lastname: Rickard
authors.forename: L J
authors.initials: LJ
authors.lastname: Orcheson
authors.forename: H H
authors.initials: HH
authors.lastname: Fong
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D002072:Butylene Glycols / Q000627:therapeutic use*; D002273:Carcinogens; D004043:Dietary Fiber; D005260:Female; D017705:Lignans / Q000652:urine*; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002072:Butylene Glycols; D002273:Carcinogens; D004043:Dietary Fiber; D017705:Lignans; D015127:9,10-Dimethyl-1,2-benzanthracene; C060283:secoisolariciresinol