HA metabolism in skin homeostasis and inflammatory disease

- Hyaluronan (HA) is an important component of extracellular matrix network with its bulk in the body deposited to the skin.
- HA participates in the process of wound closure.
- HA is postulated to regulate skin inflammation in a size/concentration dependent manner.
- Inflammation initiated by UV radiation affects HA metabolism.
- HA has been suggested or is currently applied for the treatment of several skin disorders.

Hyaluronan (HA), an unsulfated glycosaminoglycan, is an important component of the complex extracellular matrix network which surrounds and supports cells in tissues. HA is detected in all vertebrate tissues, but the bulk of HA is produced and deposited in the skin. In this review we focus on the role of HA in skin-associated inflammatory disease and wound healing. Properties of HA are directly dependent on its molecular weight. Thus, high molecular weight HA (HMWHA) is deposited in normal tissues during homeostasis and promotes their stability whereas low molecular weight HA fragments (LMWHA), on the other hand, may arise from enzymatic or chemical activities. The degradation of HMWHA to LMWHA fragments, often leads to the generation of biologically active oligosaccharides with different properties and postulated functions in wound scar formation and inflammation. More detailed studies of HA involvement in skin-associated inflammatory disease may result in novel treatment modalities.

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