Hyaluronic acid (Hyaluronan) (HA)

Hyaluronic acid (HA) is a high-molecular-weight glycosaminoglycan that is a critical component of the synovial fluid and the extracellular matrix of articular cartilage. In the joint synovial environment, HA provides essential lubrication and viscoelastic support, acting as a shock absorber during high-impact activities and a lubricant during slow movements (StatPearls, 2023). It is synthesized by type B synoviocytes and helps maintain joint homeostasis by regulating fluid balance and protecting the cartilage surface. In degenerative joint diseases like osteoarthritis, the concentration and molecular weight of endogenous HA are significantly reduced, leading to increased friction and mechanical degradation of the joint (PubMed, PMID: 21443021). Therapeutic interventions, known as viscosupplementation, involve the intra-articular injection of exogenous HA to restore the rheological properties of the synovial fluid and alleviate pain. Additionally, HA interacts with cell surface receptors such as CD44 to mediate anti-inflammatory and chondroprotective signaling pathways (NIH, PubChem CID 24759). This interaction helps to inhibit the production of pro-inflammatory cytokines and matrix metalloproteinases that contribute to cartilage breakdown. Clinical use of HA aims to bridge the gap between conservative treatments and surgical options for patients with symptomatic joint degeneration.

Other names

HyaluronanSodium hyaluronateHAHyaluronatePoly(beta-glucuronic acid-[1->3]-beta-N-acetylglucosamine-[1->4])

Viscosupplementation to restore the rheological properties of synovial fluid, providing mechanical lubrication and shock absorption, while also exerting anti-inflammatory and chondroprotective effects through interaction with CD44 receptors.