title: Inhibition of Helicobacter pylori adhesion to human gastric adenocarcinoma epithelial cells by aqueous extracts and pectic polysaccharides from the roots of Cochlospermum tinctorium A. Rich. and Vernonia kotschyana Sch. Bip. ex Walp.
abstract: In Malian traditional medicine infusions of the roots of Vernonia kotschyana or Cochlospermum tinctorium in water are used for treating gastric ulcer. Helicobacter pylori is known to play a major role in gastric ulcer development, and it was of interest to evaluate a potential anti-adhesive activity towards H. pylori by crude water extracts and isolated polysaccharide fractions from the roots of V. kotschyana and C. tinctorium. The inhibitory effects were examined by an in vitro flow cytometric assay using human gastric adenocarcinoma epithelial cells, where fluorescent-labeled H. pylori were pre-treated with the test fractions. The crude extract Ctw50 from C. tinctorium, containing a mixture of inulin, pectic polysaccharides, phenols and protein, led to a 43% reduction of bacterial attachment. The isolated pectic type fractions CtwA1 and CtwA2 from C. tinctorium, and Vko-I from V. kotschyana resulted in approximately 30% inhibition of H. pylori adhesion. These fractions consist of rhamnogalacturonan backbones with side chains of arabinogalactans and/or arabinans. The low degree of uronic acids in the fractions compared to anti-adhesive polysaccharides reported previously, suggests that the neutral side chains might play a role in the binding of bacterial adhesins. The fraction Vko-III.1 from V. kotschyana consisting mainly of galacturonic acid resulted only in a 19% inhibition of H. pylori adhesion. The anti-adhesive properties shown by the crude water extracts and isolated polysaccharide fractions in the present study might partly explain the anti-ulcer activities by the roots of V. kotschyana and C. tinctorium.
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway. Electronic address: k.t.inngjerdingen@farmasi.uio.no.
authors.forename: Kari Tvete
authors.initials: KT
authors.lastname: Inngjerdingen
authors.affiliation: Institute of Pharmaceutical Biology and Phytochemistry, University of Münster, Corrensstrasse 48, D-48149 Münster, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Thöle
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway; Department of Traditional Medicine, BP 1746 Bamako, Mali.
authors.forename: Drissa
authors.initials: D
authors.lastname: Diallo
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway.
authors.forename: Berit Smestad
authors.initials: BS
authors.lastname: Paulsen
authors.affiliation: Institute of Pharmaceutical Biology and Phytochemistry, University of Münster, Corrensstrasse 48, D-48149 Münster, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hensel
mesh_terms: D000230:Adenocarcinoma / Q000382:microbiology*; D031212:Bixaceae / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects; D004847:Epithelial Cells / Q000187:drug effects; D005685:Galactans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D008519:Medicine, Traditional; D010368:Pectins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D013276:Stomach Ulcer / Q000382:microbiology*; D035741:Vernonia / Q000737:chemistry*
chemical_list: D005685:Galactans; D010636:Phenols; D010936:Plant Extracts; D011134:Polysaccharides; D010368:Pectins; C005653:arabinogalactan
keywords: Anti-adhesion; Cochlospermum tinctorium (Cochlospermaceae); Helicobacter pylori; Inulin; Pectic polysaccharides; Vernonia kotschyana (Asteraceae)