Heparin-like glycosaminoglycans (HLGAGs) (HLGAGs)

Heparin-like glycosaminoglycans (HLGAGs) are complex, highly acidic linear polysaccharides found on the cell surface and within the extracellular matrix of virtually all animal tissues (NCBI, 2023). They consist of repeating disaccharide units that undergo extensive enzymatic modification, including sulfation, which creates specific binding sites for a wide array of proteins (PubMed, PMID: 22403071). Biologically, HLGAGs are essential regulators of blood coagulation, primarily through their interaction with antithrombin III, and serve as critical co-receptors for growth factors, cytokines, and morphogens that govern cell signaling and development (StatPearls, 2024). In clinical practice, exogenous HLGAGs like heparin and its derivatives are mainstay anticoagulants used to treat and prevent thromboembolic events (PubChem). Furthermore, HLGAGs are implicated in various pathologies, including cancer metastasis and viral infections, where they facilitate pathogen attachment and entry (Nature Communications, 2020). For instance, heparan sulfate has been identified as a necessary co-receptor for the SARS-CoV-2 spike protein, facilitating its interaction with ACE2. Therapeutic strategies targeting HLGAGs include the use of heparin mimetics to block growth factor signaling in tumors or the administration of neutralizing agents like protamine sulfate in cases of heparin overdose.

Other names

Heparan sulfate glycosaminoglycansHSGAGsHeparinoidsHeparan sulfateHeparin

HLGAGs and their analogs primarily function by binding to and activating antithrombin III, which accelerates the inhibition of thrombin (Factor IIa) and Factor Xa (StatPearls, 2024). They also act as competitive inhibitors or decoys to prevent the binding of growth factors or pathogens to endogenous cell-surface heparan sulfate (PubMed, PMID: 32843424).