Hyaluronic acid and related extracellular glycosaminoglycans (HA/GAGs)

Hyaluronic acid (HA) and related extracellular glycosaminoglycans (GAGs) are essential linear polysaccharides that constitute a major part of the extracellular matrix in vertebrate tissues. HA is a unique, non-sulfated GAG that provides structural integrity, lubrication, and hydration, particularly in the synovial fluid of joints and the vitreous humor of the eye (PubChem CID 24759; StatPearls: Hyaluronic Acid). These molecules interact with specific cell-surface receptors, most notably CD44 and RHAMM, to regulate critical cellular processes such as adhesion, migration, and proliferation (UniProt P16070; PubMed PMC3967202). In pathological conditions, the dysregulation of HA and GAG metabolism is linked to osteoarthritis, chronic inflammation, and the progression of various cancers where they facilitate tumor cell motility and matrix remodeling (PubMed PMC3967202). Therapeutically, HA is utilized as a viscosupplement for joint pain and as a dermal filler, while hyaluronidase enzymes are employed to degrade these molecules to enhance drug absorption or reduce tissue edema (StatPearls: Hyaluronic Acid). The biological activity of these molecules is highly dependent on their molecular weight, with high-molecular-weight forms typically promoting tissue stability and low-molecular-weight fragments often signaling tissue injury and inflammation (PubChem CID 24759).

Other names

HyaluronanHyaluronateMucopolysaccharidesAcidic glycosaminoglycansExtracellular matrix polysaccharides

Viscosupplementation, receptor binding (CD44/RHAMM) to modulate signaling, enzymatic degradation of the extracellular matrix, and osmotic hydration of tissues.