title: Infrared radiation-induced matrix metalloproteinase in human skin: implications for protection.
abstract: Human skin is exposed to infrared radiation (IR) from natural and artificial sources. In previous studies, near IR radiation (IRA; 760-1,440 nm) was shown to elicit a retrograde mitochondrial signaling response leading to induction of matrix metalloproteinase-1 (MMP-1) expression. These studies, however, have exclusively employed cultured human skin fibroblasts ex vivo. Here, we have assessed the in vivo relevance of these observations by exposing healthy human skin in vivo to physiologically relevant doses of IRA. Eighty percent of the tested individuals responded to IRA radiation by upregulating of MMP-1 expression. Specifically, IRA irradiation caused increased expression of MMP-1 in the dermis, but not in the epidermis. Raman spectroscopy revealed that IRA radiation also caused a significant decrease in the antioxidant content of human skin. In vitro studies had previously shown that IRA-induced MMP-1 expression was mediated through an oxidative stress response, which originates from the mitochondrial electron transport chain. We now report that incubation of cultured human dermal fibroblasts or treatment of human skin with specific antioxidants prevented IRA radiation-induced MMP-1 expression in vitro and in vivo. Thus, IRA irradiation most likely promotes premature skin aging and topical application of appropriate antioxidants represents an effective photoprotective strategy.
authors.affiliation: Cell Biology/Molecular Ageing Research, Institut fuer Umweltmedizinische Forschung, Heinrich-Heine-University Düsseldorf gGmbH, Duesseldorf, Germany. peet@gmx.de
authors.forename: Peter
authors.initials: P
authors.lastname: Schroeder
authors.forename: Juergen
authors.initials: J
authors.lastname: Lademann
authors.forename: Maxim E
authors.initials: ME
authors.lastname: Darvin
authors.forename: Helger
authors.initials: H
authors.lastname: Stege
authors.forename: Corinna
authors.initials: C
authors.lastname: Marks
authors.forename: Susanne
authors.initials: S
authors.lastname: Bruhnke
authors.forename: Jean
authors.initials: J
authors.lastname: Krutmann
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology; D002478:Cells, Cultured; D020405:Dermis / Q000166:cytology / Q000378:metabolism; D015536:Down-Regulation; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D007259:Infrared Rays; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000096:biosynthesis* / Q000378:metabolism; D061965:Matrix Metalloproteinase Inhibitors; D008875:Middle Aged; D012867:Skin / Q000201:enzymology* / Q000528:radiation effects*; D014018:Tissue Distribution; D015854:Up-Regulation
chemical_list: D000975:Antioxidants; D061965:Matrix Metalloproteinase Inhibitors; D020781:Matrix Metalloproteinase 1