Glycosaminoglycan (GAG) (GAG)

Glycosaminoglycans (GAGs), historically referred to as acid mucopolysaccharides, are complex, long-chain linear polysaccharides consisting of repeating disaccharide units, typically comprising an amino sugar and a uronic acid or galactose (Wikipedia, 2023). These molecules are highly negatively charged due to the presence of sulfate and carboxyl groups, allowing them to attract water and provide structural support and lubrication within the extracellular matrix (PubChem, 2024). GAGs play vital roles in cell signaling, regulation of coagulation, and tissue repair by interacting with various proteins and growth factors (NCBI, 2022). Pathologically, the deficiency of specific lysosomal enzymes leads to the accumulation of GAGs, resulting in a group of metabolic disorders known as mucopolysaccharidoses (MPS), which cause progressive damage to the skeleton, heart, and central nervous system (StatPearls, 2023). Therapeutic strategies include enzyme replacement therapies (ERTs) like laronidase or idursulfase, which aim to degrade accumulated GAGs, and the use of GAGs themselves, such as heparin, as clinical anticoagulants or the neutralization of such GAGs by agents like protamine sulfate (NIH, 2021).

Other names

Acid mucopolysaccharideMucopolysaccharideAcidic glycosaminoglycan

Enzymatic degradation of accumulated substrates via enzyme replacement therapy; ionic neutralization of polyanionic chains by cationic agents.