title: Inhibitory effect of orally-administered sulfated polysaccharide ascophyllan isolated from ascophyllum nodosum on the growth of sarcoma-180 solid tumor in mice.
abstract: We evaluated the antitumor activity of crude extract and ascophyllan prepared from Ascophyllum nodosum in sarcoma-180 solid tumor-bearing mice with continuous intraperitoneal (i.p.) administration at a dose of 50 mg/kg body weight/day or oral administration at a dose of 500 mg/kg body weight/day. Ascophyllan and crude extract administered via the oral route showed greater antitumor effects than via i.p. route, and the tumor sizes in mice treated with ascopyllan and crude extract were reduced by a mean of 68.7±6.8% and 42.4±24.8% by the oral route, and 41.4±16.1% and 13.6±20.6% by i.p. route compared to control mice. Splenic natural killer cell activity in the mice treated with ascophyllan and crude extract by i.p. route was significantly enhanced, while only a slight increase of this activity was observed in orally-treated mice. Furthermore, increase in spleen weight of tumor-bearing mice was slightly suppressed by oral administration of ascophyllan, whereas i.p. administration resulted in further enlargement. Analysis of serum cytokines revealed that oral treatment with ascophyllan resulted in significant increase of tumor necrosis factor-α and interleukin-12 levels. Since ascophyllan showed no direct cytotoxic effect on sarcoma-180 cells, orally-administered ascophyllan is suggested to exhibit its antitumor activity through the activation of the host immune system.
authors.affiliation: Division of Biochemistry, Faculty of Fisheries, Nagasaki University, Bunkyo-machi 1-14, Nagasaki 852-8521, Japan. t-oda@nagasaki-u.ac.jp.
authors.forename: Zedong
authors.initials: Z
authors.lastname: Jiang
authors.forename: Ryogo
authors.initials: R
authors.lastname: Abu
authors.forename: Shogo
authors.initials: S
authors.lastname: Isaka
authors.forename: Satoru
authors.initials: S
authors.lastname: Nakazono
authors.forename: Mikinori
authors.initials: M
authors.lastname: Ueno
authors.forename: Takasi
authors.initials: T
authors.lastname: Okimura
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Oda
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D044646:Ascophyllum / Q000737:chemistry*; D001835:Body Weight; D045744:Cell Line, Tumor; D016207:Cytokines / Q000097:blood / Q000378:metabolism; D007274:Injections, Intraperitoneal; D007694:Killer Cells, Natural / Q000187:drug effects; D008297:Male; D051379:Mice; D008970:Molecular Weight; D009929:Organ Size; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D011134:Polysaccharides / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D012510:Sarcoma 180 / Q000188:drug therapy / Q000276:immunology / Q000473:pathology; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D047368:Tumor Burden / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D016207:Cytokines; D010936:Plant Extracts; D011134:Polysaccharides; C058519:ascophyllin
keywords: Ascophyllan; antitumor activity; host immune system; intraperitoneal administration; oral administration; sarcoma-180 cells