Sjerobabski Masnec Ines, Poduje Sanja
Department of Dermatovenerology, University Hospital Sestre milosrdnice, Zagreb, Croatia.
Coll Antropol. 2008 Oct;32 Suppl 2:177-80.
Among harmful environmental factors that contribute to extrinsic aging, long-term effects of repeated exposure to ultraviolet light are the most significant and are referred to as photoaging. Photoaging is a multisystem degenerative process that involves the skin and skin support system. It is a cumulative process and depends primarily on the degree of sun exposure and skin pigment. The epidermis and dermis are both affected by UVB, but the dermis is also affected to a significant extent by UVA. It has long been thought that the majority of human photo-lesions due to UVB rays, now it is believed that UVA play a substantial role in photoaging. Photoaging affects the sun-exposed areas and is characterized clinically by fine and coarse wrinkling, roughness, dryness, laxity, teleangiectasia, loss of tensile strength and pigmentary changes. There is also an increase in development of benign and malignant neoplasms on photoaged skin. During the years the progress has been made in understanding the photoaging in human skin. UV irradiation invokes a complex sequence of specific molecular responses that damage skin connective tissue. Restriction of UV irradiation and the use of high-protection, broad-spectrum sunscreens may slow progression of photoaging.
在导致外源性衰老的有害环境因素中，反复暴露于紫外线的长期影响最为显著，被称为光老化。光老化是一个涉及皮肤及皮肤支持系统的多系统退行性过程。它是一个累积过程，主要取决于阳光照射程度和皮肤色素。表皮和真皮都会受到中波紫外线（UVB）的影响，但长波紫外线（UVA）对真皮也有很大程度的影响。长期以来人们一直认为大多数人类光损伤是由UVB射线造成的，现在人们相信UVA在光老化中起重要作用。光老化影响暴露于阳光的部位，临床特征为细纹和粗皱纹、粗糙、干燥、松弛、毛细血管扩张、抗张强度丧失和色素变化。光老化皮肤发生良性和恶性肿瘤的几率也会增加。多年来，在理解人类皮肤光老化方面取得了进展。紫外线照射引发一系列复杂的特定分子反应，损害皮肤结缔组织。限制紫外线照射和使用高防护、广谱防晒霜可能会减缓光老化进程。
