Connective tissue alterations in skin exposed to natural and therapeutic UV-radiation.

Aging of human skin represents a complex situation where several factors contribute to the age-related changes. One of these factors relates to UV-radiation, but the exact mechanistic details are not well established. Several morphologic studies have indicated definite changes in the quantitative aspects of dermal connective tissue components, collagen and elastin. Also, recent biochemical studies have suggested that UV-irradiation can alter the metabolism of these proteins in the skin. This review summarizes the current state of knowledge of the effects of natural and therapeutic UV-radiation on dermal connective tissue, and further delineates additional research needs necessary for disclosure of the exact mechanistic details of the aging processes in human skin.