【 文献重点摘要 】
 

Dermatology is a field that strives not only to alleviate skin disease (therapeutics) but also to improve the perception of wellness (cosmetics). Thus, in this special issue of Glycobiology, it seems appropriate to discuss the biology of a glycosaminoglycan, called hyaluronic acid (hyaluronan, or HA), that has become the most popular agent today for intradermal injections to improve wrinkles and other cosmetic defects. HA is a simple linear polymer in which a simple disaccharide is repeated thousands of time, thereby creating a huge hydrophilic molecule that confers a large volume of hydration and contributes to the turgor and flexibility of healthy skin. Beyond cosmetic considerations, however, HA also has important biological and physiological functions that were largely under-appreciated until recently. New research has confirmed that HA is dynamically produced by most skin cells, not only fibroblasts (the cells that make most of the skin’s extracellular matrix) but also by keratinocytes in the outer protective layer (epidermis). For both fibroblasts and keratinocytes, HA plays a regulatory role in controlling cell physiology through interaction of extracellular HA with a major cell-surface receptor, CD44. This interaction mediates intracellular signaling both directly and indirectly, through CD44 interactions with the cytoskeleton and with EGF and TGFβ receptors. Furthermore, degradation of HA by specific hyaluronidase enzymes produces HA fragments that can help to regulate inflammatory processes. In this review, current knowledge about the role of HA in skin inflammation and wound healing are reviewed and possible future applications of such knowledge discussed.

Keywords

fibrosis, glycosaminoglycan, inflammation, skin, wound healing

皮肤科是一个不仅致力于减轻皮肤病(治疗学)，而且还致力于改善人们对健康(美容)的认知的领域。因此，在本期“糖生物学”特刊中，讨论一种名为透明质酸(透明质酸，或HA)的糖胺聚糖的生物学似乎是合适的，这种糖胺聚糖已成为当今最受欢迎的皮内注射制剂，用于改善皱纹和其他美容缺陷。HA是一种简单的线性聚合物，简单的双糖在其中重复数千次，从而产生一个巨大的亲水分子，提供大量的水合，有助于健康皮肤的膨胀和弹性。然而，除了美容方面的考虑外，HA还具有重要的生物学和生理功能，直到最近，这些功能还在很大程度上被低估了。新的研究证实，透明质酸是由大多数皮肤细胞动态产生的，不仅是成纤维细胞(构成皮肤细胞外基质的细胞)，而且还由外层保护层(表皮)的角质形成细胞产生。对于成纤维细胞和角质形成细胞，HA都通过细胞外HA与主要的细胞表面受体CD44相互作用来调控细胞生理。这种相互作用通过CD44与细胞骨架、表皮生长因子和转化生长因子β受体的相互作用，直接或间接地介导细胞内信号转导。此外，透明质酸被特定的透明质酸酶降解，产生有助于调节炎症过程的HA片段。本文综述了透明质酸在皮肤炎症和伤口愈合中的作用，并讨论了这些知识未来可能的应用。

关键词

纤维化，糖胺聚糖，炎症，皮肤，伤口愈合