title: Intestinal absorption of fucoidan extracted from the brown seaweed, Cladosiphon okamuranus.
abstract: The aim of this study was to examine the absorption of fucoidan through the intestinal tract. Fucoidan (0.1, 0.5, 1.0, 1.5 and 2.0 mg/mL) was added to Transwell inserts containing Caco-2 cells. The transport of fucoidan across Caco-2 cells increased in a dose-dependent manner up to 1.0 mg/mL. It reached a maximum after 1 h and then rapidly decreased. In another experiment, rats were fed standard chow containing 2% fucoidan for one or two weeks. Immunohistochemical staining revealed that fucoidan accumulated in jejunal epithelial cells, mononuclear cells in the jejunal lamina propria and sinusoidal non-parenchymal cells in the liver. Since we previously speculated that nitrosamine may enhance the intestinal absorption of fucoidan, its absorption was estimated in rats administered N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in their drinking water. Rats were fed 0.2% fucoidan chow (BBN + 0.2% fucoidan rats), 2% fucoidan chow (BBN + 2% fucoidan rats) and standard chow for eight weeks. The uptake of fucoidan through the intestinal tract seemed to be low, but was measurable by our ELISA method. Fucoidan-positive cells were abundant in the small intestinal mucosa of BBN + 2% fucoidan rats. Most fucoidan-positive cells also stained positive for ED1, suggesting that fucoidan was incorporated into intestinal macrophages. The uptake of fucoidan by Kupffer cells was observed in the livers of BBN + 2% fucoidan rats. In conclusion, the absorption of fucoidan through the small intestine was demonstrated both in vivo and in vitro.
authors.affiliation: Graduate School of Health Sciences, Gunma University, Maebashi, Gunma 371-8514, Japan. mine@gunma-u.ac.jp.
authors.forename: Takeaki
authors.initials: T
authors.lastname: Nagamine
authors.affiliation: Graduate School of Health Sciences, Gunma University, Maebashi, Gunma 371-8514, Japan. nkyoumi@gunma-u.ac.jp.
authors.forename: Kyoumi
authors.initials: K
authors.lastname: Nakazato
authors.affiliation: Graduate School of Health Sciences, Gunma University, Maebashi, Gunma 371-8514, Japan. besu13bikky@yahoo.co.jp.
authors.forename: Satoru
authors.initials: S
authors.lastname: Tomioka
authors.affiliation: South Product, Co., Ltd., Uruma, Okinawa 904-1103, Japan. miha.south@nifty.com.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Iha
authors.affiliation: Graduate School of Health Sciences, Gunma University, Maebashi, Gunma 371-8514, Japan. nkyoumi@gunma-u.ac.jp.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Nakajima
mesh_terms: D000818:Animals; D018938:Caco-2 Cells; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007408:Intestinal Absorption; D007583:Jejunum / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008297:Male; D011134:Polysaccharides / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D012624:Seaweed / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; C007789:fucoidan