Enhanced expression of cylooxygenase-2 by UV in aged human skin in vivo

Abstract

Prostaglandins (PGs) induced by UV may play important roles in UV-induced inflammation, photocarcinogenesis, and photoaging processes in human skin. The age-related PGE 2 production and cyclooxygenase-2 (COX-2) expression in the human skin in vivo remain unclear. The purpose of this study was to examine the influence of aging on UV-induced PGE 2 production and COX-2 expression in human skin in vivo. We found that aged human skin produces higher amounts of PGE 2 than young skin, when exposed to UV. The inductions of COX-2 mRNA and protein by UV in aged skin were higher than those in the young skin, whereas COX-1 mRNA expression remained unchanged. Aged human macrophage expressed higher amounts of PGE 2 and COX-2 protein constitutively, and also induced these species after LPS treatment more so than young cells. Our data suggest that skin aging may increase susceptibility to the development of skin cancer and photoaging, by enhanced PGE 2 and COX-2 expression due to UV in human skin in vivo.