title: Human skin fibroblast telomeres are shortened after ultraviolet irradiation.
abstract: OBJECTIVE
  Telomere length was used as a biomarker of cell senescence to explore the role of telomere shortening in photoageing induced by ultraviolet A (UVA) light.
  
  
  METHODS
  Real-time polymerase chain reaction was used to determine telomere length in cultured human fibroblasts of different  generations and after exposure to UVA at doses up to 10 000 mJ/cm(2). Twoway analysis of variance was used to determine whether passaging or UVA was the main factor contributing to telomere shortening.
  
  
  RESULTS
  In nonirradiated cells, telomere length was inversely related to cell  generation number. In fibroblasts exposed to UVA at a dose of 1000 or 10 000 mJ/cm(2), telomere length was significantly shorter than that of nonirradiated controls and was negatively related to UVA dose.
  
  
  CONCLUSIONS
  Telomere length and subsequent cell viability may be affected by  UVA irradiation. DNA damage caused by UVA irradiation may initiate the photoageing process and telomeres may be a useful new target for attempts to prevent photoageing.
authors.affiliation: Department of Dermatology, First Affiliated Hospital of China Medical University Hospital One, Shenyang, Liaoning, China.
authors.forename: H-M
authors.initials: HM
authors.lastname: Ma
authors.forename: W
authors.initials: W
authors.lastname: Liu
authors.forename: P
authors.initials: P
authors.lastname: Zhang
authors.forename: X-Y
authors.initials: XY
authors.lastname: Yuan
mesh_terms: D002470:Cell Survival / Q000528:radiation effects; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000528:radiation effects; D002648:Child; D005347:Fibroblasts / Q000502:physiology* / Q000528:radiation effects; D006801:Humans; D008297:Male; D012867:Skin / Q000166:cytology; D016615:Telomere / Q000378:metabolism* / Q000528:radiation effects; D059506:Telomere Shortening / Q000528:radiation effects*; D014466:Ultraviolet Rays