Heparin-like
glycans with diverse
disaccharide composition and high
anticoagulant activity have been described in several families of marine mollusks. The present work focused on the structural characterization of a new
heparan sulfate (HS)-like
polymer isolated from the mollusk Nodipecten nodosus (Linnaeus, 1758) and on its
anticoagulant and antithrombotic properties. Total
glycans were extracted from the mollusk and fractionated by
ethanol precipitation. The main component (>90%) was identified as HS-like
glycosaminoglycan, representing approximately 4.6 mg g(-1) of dry tissue. The mollusk HS resists degradation with
heparinase I but is cleaved by
nitrous acid. Analysis of the mollusk
glycan by one-dimensional (1)H, two-dimensional correlated spectroscopy, and heteronuclear single quantum coherence nuclear magnetic resonance revealed characteristic signals of
glucuronic acid and
glucosamine residues. Signals corresponding to anomeric
protons of nonsulfated, 3- or 2-sulfated
glucuronic acid as well as N-sulfated and/or 6-sulfated
glucosamine were also observed. The mollusk HS has an
anticoagulant activity of 36 IU mg(-1), 5-fold lower than porcine
heparin (180 IU mg(-1)), as measured by the activated partial thromboplastin time assay. It also inhibits
factor Xa (IC(50) = 0.835 microg ml(-1)) and
thrombin (IC(50) = 9.3 microg ml(-1)) in the presence of
antithrombin. In vivo assays demonstrated that at the dose of 1 mg kg(-1), the mollusk HS inhibited
thrombus growth in photochemically injured arteries. No
bleeding effect,
factor XIIa-mediated
kallikrein activity, or toxic effect on fibroblast cells was induced by the invertebrate HS at the antithrombotic dose.