glykosaminoglykanien

Glykosaminoglykanien, commonly called glycosaminoglycans (GAGs), are long unbranched polysaccharides composed of repeating disaccharide units that include an amino sugar (glucosamine or galactosamine) linked to a uronic acid. They are typically sulfated and carry a high negative charge, enabling them to bind water and ions.

These molecules are integral components of the extracellular matrix and cell surfaces. They form complexes with core proteins to produce proteoglycans, which contribute to tissue resilience and signal transduction. GAGs are found in cartilage, tendon, bone, and in basement membranes, where they influence cell adhesion, migration, and the distribution of growth factors.

Common classes of GAGs include heparan sulfate, heparin, chondroitin sulfate, dermatan sulfate, keratan sulfate, and hyaluronic acid. Each has distinct sulfation patterns and biological functions. For example, heparan sulfate regulates blood coagulation and cell signaling, while hyaluronic acid is crucial for tissue hydration and wound healing.

Abnormal glycosaminoglycan metabolism underlies several lysosomal storage disorders, such as mucopolysaccharidoses, characterized by progressive accumulation of GAGs and multi‑organ dysfunction. Therapeutic approaches include enzyme replacement and gene therapy, aiming to restore normal GAG degradation.

Research into GAGs continues to uncover their roles in development, immunity, and disease. They are targets for drug delivery systems and anti‑angiogenic therapies, highlighting their significance in both basic biology and clinical applications.