Influence of molecular weight of chemically sulfated citrus pectin fractions on their antithrombotic and bleeding effects.

Laboratório de Química de Carboidratos, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, CP 19046, CEP 81.531-980, Curitiba, PR, Brazil.
Thrombosis and Haemostasis (Impact Factor: 5.76). 05/2009; 101(5):860-6. DOI: 10.1160/TH08-08-0556
Source: PubMed

ABSTRACT Evaluated were the anticoagulant and antithrombotic activities, and bleeding effect of two chemically sulfated polysaccharides, obtained from citric pectin, with different average molar masses. Both low-molecular-weight (Pec-LWS, 3,600 g/mol) and high-molecular-weight sulfated pectins (Pec-HWS, 12,000 g/mol) had essentially the same structure, consisting of a (1-->4)-linked alpha-D-GalpA chain with almost all its HO-2 and HO-3 groups substituted by sulfate. Both polysaccharides had anticoagulant activity in vitro, although Pec-HWS was a more potent antithrombotic agent in vivo, giving rise to total inhibition of venous thrombosis at a dose of 3.5 mg/kg body weight. Surprisingly, in contrast with heparin, Pec-HWS and Pec-LWS are able to directly inhibit alpha-thrombin and factor Xa by a mechanism independent of antithrombin (AT) and/or heparin co-factor II (HCII). Moreover, Pec-HWS provided a lower risk of bleeding than heparin at a dose of 100% effectiveness against venous thrombosis, indicating it to be a promising antithrombotic agent.

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