A synthetic carbohydrate molecule that can act as an anticoagulant, with its function reversible, is reported in a paper published online this week in Nature Chemical Biology. These findings, demonstrated in mice, identify a new strategy for designing safer and more effective anticoagulant drugs.
The naturally occurring molecule heparin is commonly administered as an anticoagulant, to thin blood. However, since a widespread 2008 heparin contamination, researchers have searched for safer alternatives. Low-molecular-weight heparins, which have much shorter chains of sugars than naturally found in heparin, are now frequently used instead, but the effects of these compounds cannot - unlike natural heparin - be reversed by the peptide protamine, leading to the potential for uncontrolled bleeding.
Jian Liu, Robert Linhardt and colleagues report the synthesis and testing of defined carbohydrate sequences that are longer than normal low-molecular-weight heparins. They observe that sequences containing 12 sugar monomers are active anticoagulants in mice and their function can be reversed by protamine.