title: The medicinal plant Porana volubilis contains polysaccharides with anticoagulant activity mediated by heparin cofactor II.
abstract: We searched for polysaccharides with anticoagulant activity and inhibitory action on platelet aggregation induced by collagen in 59 species of medicinal plants. We then concentrated our studies on the polysaccharide from the species Porana volubilis, which showed the highest anticoagulant activity among the plants tested. The polysaccharide from this species has an average molecular mass of approximately 10 kDa, contains mainly galactose, galacturonic acid, and mannose but no sulfate esters. Its anticoagulant activity is mediated by the enhancement of thrombin inhibition that in turn is mediated by heparin cofactor II but not by antithrombin. The galacturonic acid residues are essential for activity since after reduction of its carboxyl groups the anticoagulant activity disappears. Our report is the first description of a natural nonsulfated polysaccharide from higher plants with anticoagulant activity, which may constitute a new source of compounds with action on coagulation and, perhaps, on thrombosis.
authors.affiliation: Laboratório de Tecido Conjuntivo, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Caixa Postal 68041, RJ 21941-590, Rio de Janeiro, Brazil.
authors.forename: Seon-Joo
authors.initials: SJ
authors.lastname: Yoon
authors.forename: Mariana S
authors.initials: MS
authors.lastname: Pereira
authors.forename: Mauro S G
authors.initials: MS
authors.lastname: Pavão
authors.forename: Jae-Kwan
authors.initials: JK
authors.lastname: Hwang
authors.forename: Yu-Ryang
authors.initials: YR
authors.lastname: Pyun
authors.forename: Paulo A S
authors.initials: PA
authors.lastname: Mourão
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology*; D001780:Blood Coagulation Tests; D004357:Drug Synergism; D015844:Heparin Cofactor II / Q000494:pharmacology*; D006603:Hexuronic Acids; D010946:Plants, Medicinal / Q000737:chemistry*; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology; D011134:Polysaccharides / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D000925:Anticoagulants; D006603:Hexuronic Acids; D010975:Platelet Aggregation Inhibitors; D011134:Polysaccharides; C007819:galacturonic acid; D015844:Heparin Cofactor II