A non-hemorrhagic hybrid heparin/heparan sulfate with anticoagulant potential

Abstract

The structural characterization and the anticoagulant potential of a novel heparin/heparan sulfate-like compound from the heads of Litopenaeus vannamei shrimp are described. While it is distinct from either heparin or heparan sulfate, enzymatic depolymerization and nuclear magnetic resonance spectroscopy analyses revealed that this molecule does share some structural features with heparin, such as the high degree of N- and 6-O-sulfation and minor N-acetylation, and with heparan sulfate, in the glucuronic acid content. Its ability to stabilize human antithrombin explains its significant anticoagulant activity in aPTT and Factor-Xa inhibition assays. Interestingly, in contrast to mammalian heparin, the shrimp compound displayed negligible hemorrhagic effect. Together, these findings have particular interest since they reveal a novel molecule with significant anti-Xa activity coupled with low bleeding effects which make the shrimp heparin/HS-like compound a potential alternative for mammalian heparin.

Heparan sulfate and heparin interactions with proteins

“…Furthermore, HS is considered typically to adopt longer, more flexible chains in solution than heparin [10,11]. It has become apparent, however, that the designations heparin or HS are less clear-cut than this description implies, and that polysaccharides isolated from some organisms appear to be hybrid [12,13]. Indeed, HS with features approaching heparin are produced in a variety of tissues [14][15][16] and cell types [17][18][19].…”

“…Tissue-derived HS chromatographic fractions and more recently, several synthetic and defined oligosaccharides [101][102][103] have also been generated, with the purpose of exploring structure-function relationships [4,12,43,64,66,[104][105][106][107][108][109]. However, it is conceivable that the use of such fractions may misrepresent activities performed by stretches of the full-length polysaccharide.…”

NMR structural determination of unique invertebrate glycosaminoglycans endowed with medical properties

“…77 The HS/Hp hybrid aspect of the shrimp GAG has allowed to this molecule a fascinating anticoagulant activity as assessed by the aPTT method combined with the AT-dependent inhibition of factor Xa. 23 The anticoagulant activity of the invertebrate HS/Hp showed anticoagulant potentials close to the pharmaceutically employed Hp standard. This great levels of activity is correlated with the large amounts of O-and N-sulfation, especially the 3-O-sulfation in GlcN units, which is known to facilitate interaction with AT.…”

“…1,2 Interestingly, a GAG type containing structural features of both HS and Hp at the same time was recently found in the head of the shrimp L. vannamei. 23 This hybrid GAG was structurally characterized based on disaccharide composition analysis combined with liquid-state NMR spectroscopy. The resultant 1 He 13 C HSQC spectrum (anomeric region only) of this novel GAG is shown at Fig.…”

“…Among numerous invertebrate GAGs that have been studied so far in terms of both structure and function, representative examples are the holothurian fucosylated chondroitin sulfate (FucCS), 14,15 the acharan sulfate (AS) from the giant African snail Achatina fulica, 16e18 the ascidian DSs of unique sulfation patterns, 19e21 the novel HS from the bivalve Nodipecten nodosus, 22 and the hybrid HS/Hp found in the head of the shrimp Litopenaeus vannamei. 23 Like in structural analyses of mammalian GAGs, solution nuclear magnetic resonance (NMR) spectroscopy alone or combined with other techniques, has been the preferred method used in structural characterization of the invertebrate molecules. Here, this NMR-based analysis of GAGs of unique structures found exclusively in invertebrate animals is being overviewed in order to offer a straightforward technical guidance to future researches in the area.…”