title: Expression of decorin and collagens I and III in different layers of human skin in vivo: a laser capture microdissection study.
abstract: Extracellular matrix (ECM) organization is a complex process that requires the coordinated efforts of many molecules. For the regulation of collagen fiber diameter, the proteoglycan decorin appears to be of major relevance. To investigate the role of decorin in the process of (photo-)aging in more detail, full-thickness punch biopsies were isolated from human buttock skin. Single exposure with two minimal erythemal doses of solar simulated irradiation caused down-regulation of decorin mRNA in young (n = 5) and old subjects (n = 5) after 24 h. Interestingly, decorin mRNA was elevated with age. To test the hypothesis that a decreased collagen-to-decorin-ratio impairs collagen structure we also investigated collagens I and III gene expression. Both were down-regulated with increasing age and after single UV-irradiation. As determined by laser capture microdissection-quantitative real time-Polymerase chain reaction (n = 11), decorin is mostly present in the reticular dermis while being absent from the papillary dermis. Minor expression was also observed in the epidermis. However, in contrast to full-thickness skin biopsies age-dependent changes in collagens I, III, and decorin expression could not be observed with this methodology indicating technical limitations. Together with our finding that collagens I and III mRNA are similarly expressed in the reticular and papillary dermis and are down-regulated by UV, our studies support the idea of a major role of decorin in ECM organization. Altered expression of decorin mRNA in the different dermal strata and a decrease in the collagen-to-decorin ratio inflicted by both age and ultraviolet irradiation possibly affect collagen bundle diameter and subsequently the mechanical properties of human skin.
authors.affiliation: Paul Gerson Unna Skin Research Center, Beiersdorf AG, Unnastrasse 48, Box 519, 20245, Hamburg, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Lochner
authors.forename: Astrid
authors.initials: A
authors.lastname: Gaemlich
authors.forename: Kirstin Marie
authors.initials: KM
authors.lastname: Südel
authors.forename: Kirsten
authors.initials: K
authors.lastname: Venzke
authors.forename: Ingrid
authors.initials: I
authors.lastname: Moll
authors.forename: Anja
authors.initials: A
authors.lastname: Knott
authors.forename: Franz
authors.initials: F
authors.lastname: Stäb
authors.forename: Horst
authors.initials: H
authors.lastname: Wenck
authors.forename: Olaf
authors.initials: O
authors.lastname: Döring
authors.forename: Michael
authors.initials: M
authors.lastname: Böttger
authors.forename: Stefan
authors.initials: S
authors.lastname: Gallinat
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D001706:Biopsy; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism*; D024061:Collagen Type III / Q000235:genetics / Q000378:metabolism*; D058575:Decorin; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects; D005786:Gene Expression Regulation; D006801:Humans; D007834:Lasers; D042282:Microdissection / Q000379:methods; D008875:Middle Aged; D011509:Proteoglycans / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000378:metabolism* / Q000473:pathology / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D024042:Collagen Type I; D024061:Collagen Type III; C546878:DCN protein, human; D058575:Decorin; D016326:Extracellular Matrix Proteins; D011509:Proteoglycans; D012333:RNA, Messenger