NAG is a metabolic jumping-off point for a complex, enzyme-regulated polymerization process that generates glycosaminoglycans (GAG), which in turn become further organized into cartilage, bone, ligaments, tendons, sclera, and other specialized connective tissues. GAG are major structural contributors to the basement membranes of the skin and internal epithelia, the intima of the blood vessels, the heart valves, and the lens and sclera of the eye, as well as synovial fluid and the linings of the joints.
NAG is important for intestinal function. It is prominent both in the glycocalyx of the absorptive cells of the intestinal mucosa, and in the mucus that is secreted from other cells of the mucosa.
NAG is also a major component of several GAG that are prominent in the linings of the joints. The joints include the zones of friction between moving bones, and are sites where connective tissues are worn away most rapidly. Therefore the joints place a high demand on the capacity of their lining epithelia to produce new cartilage and other connective tissues