J Nutr Sci Vitaminol (Tokyo) 1999 Jun;45(3):325-36 Related Articles, Books,
LinkOut


Inhibitory effect of Cladosiphon fucoidan on the adhesion of Helicobacter pylori
to human gastric cells.

Shibata H, KimuraTakagi I, Nagaoka M, Hashimoto S, Sawada H, Ueyama S, Yokokura
T.

Yakult Central Institute for Microbiological Research, Tokyo, Japan.

We studied the inhibitory effect of Cladosiphon fucoidan on the attachment of
Helicobacter pylori (H. pylori), a gastroduodenal pathogen, to human gastric
cell lines. The bacterial binding in these cell lines was inhibited more by
Cladosiphon fucoidan (IC50 = 16-30 mg/mL), than by the fucoidan from Fucus (IC50
> 30 mg/mL). Dextran sulfate, another sulfated polysaccharide, did not inhibit
the binding at all. Pre-incubating the bacterial suspension with fucoidans
reinforced the inhibitory ability of these components, and reduced the IC50
value of Cladosiphon fucoidan to approximately 1 mg/mL. However, the binding was
not inhibited by pre-treatment of gastric cells with these components. It was
also shown that this fucoidan blocks both Leb- and sulfatide-mediated attachment
of H. pylori to gastric cells. Furthermore, fucoidan-binding proteins were found
on the H. pylori cell surface by Western blot analysis. Thus, the inhibitory
effect exerted by Cladosiphon fucoidan on binding between H. pylori and gastric
cells might result from the coating with this component of the bacterial
surface.

PMID: 10524351 [PubMed - indexed for MEDLINE]



Biomed Mater Eng 2001;11(1):55-61 Related Articles, Books, LinkOut


Effect of oligofucose derivatives on acetic acid-induced gastric ulcer in rats.

Shibata H, Nagaoka M, Takagi IK, Hashimoto S, Aiyama R, Yokokura T.

Yakult Central Institute for Microbiological Research, Kunitachi, Tokyo, Japan.
hideyuki-shibata@...

This study attempted to enhance the anti-ulcer activity of fucoidan from
Cladosiphon okamuranus TOKIDA by chemical modification with a hydrophobic group.
The suitable number of fucose residues in the effective compound was also
clarified to obtain a compound of constant quality. Degraded fucoidans were
coupled with several hydrophobic groups via Schiff bases, and their anti-ulcer
activities were determined by acetic acid-induced ulcer models in rats.
Size-fractionated oligofucose was also modified and assayed for anti-ulcer
activity. Among the modified oligofucoses, only the oligofucose-dodecylaniline
combination (OFDA) significantly promoted ulcer healing. The effective dose was
0.2 mg/kg/d. The most suitable number of fucose residues in the compound for the
anti-ulcer activity was determined to be around 12. We succeeded in enhancing
the anti-ulcer activity of Cladosiphon fucoidan by modification with
dodecylaniline. The activity of this compound was comparable or greater than
that of typical anti-ulcer agents. By determination of the optimal OF chain
length for the anti-ulcer activity of OFDA, it became possible to obtain OFDA of
constant quality.

PMID: 11281579 [PubMed - indexed for MEDLINE]