Hyaluronan


 * A high molecular weight GAG (different from GAGs in proteoglycans) composed of repeating units of N-acetylglucosamine and glucuronic acid
 * Roughly 1 million molecular weight
 * Hyaluronan is highly hydrophilic
 * Each glucuronic acid contains one carboxyl group
 * Hyaluronan molecules in water expand in volume up to 1000 times and forma a loose hydrated matrix, which allows hyaluronan to have several roles in ECM including a space filler that provides the compressive strength of ECM and lubrication between interfaces
 * The formed highly hydrated network allows hyaluronan to act as a sieve, restricting the movement of pathogens, plasma proteins, and proteases
 * Hyaluronan can scavenge free radicals that are responsible for inflammation
 * Can play a protective role in engineered tissues by reducing the risk of inflammation