The many faces of hyaluronan
Hyaluronic acid is generally well-known substance that is traditionally used not only in cosmetics. Following text provides supplementary information and presents a broader view of the effects variability of this substance and interesting insights into the mechanisms of action. Hyaluronic acid cannot be seen only as effective moisturiser. In dependence of the molecular weight of polysaccharide are presented comparisons of TEWL measurements, Sebum reduction, changes in tumour necrosis factor-alpha release, gene expression, the influence of the extracellular matrix, and others.Text is a basic introduction to the effects of known substance based on its molecular weight, where the data for each range of molecular weight are based on the results of a study measuring the impact of cosmetic raw materials in-vitro. These data show a strong correlation between the molecular weight of hyaluronan and its effect.
Hyaluronic acid (HA) is a linear polysaccharide composed of two regularly alternating monosaccharides, D-glucuronic acid and N-acetylglucosamine (Figure 1). By structure it is classified among glycosaminoglycans (chondroitin sulphate, heparan sulphate, dermatan sulfate, keratan sulphate, etc.), among which it is exceptional in that its molecule is not sulphated or otherwise modified. It is estimated that the total amount of HA in all tissues of the human body is approximately 15 g, of which about half is present in the skin. Here, HA (along with other ingredients, such as collagen, elastin, proteoglycans and glycoproteins) is the main component of the extracellular matrix.
It was this fact, in the second half of the 20th century, that prompted various research centres to take an increasing interest in HA, its structure, metabolism, biological effects and, above all, application. As a result, HA is now successfully used in surgery (mainly for its anti-adhesive properties), in otorhinolaryngology and ophthalmology (for its enormous capacity to bind water and moisten the mucous membranes), in orthopaedics and veterinary medicine (for ...