title: Telomere length of the skin in association with chronological aging and photoaging.
abstract: BACKGROUND
  Telomere shortening has been implicated in cellular senescence, which may cause certain aging phenotypes.
  
  
  OBJECTIVE
  To reveal whether telomere shortening is associated with chronological aging and/or photoaging of the skin, we measured telomere length in the epidermis and in the dermis from sun-protected and from sun-exposed sites of the skin.
  
  
  METHODS
  Seventy-six specimens of epidermis from sun-protected sites and 24 specimens of epidermis from sun-exposed sites were analyzed. Sixty specimens of the dermis were also analyzed. In six cases, epidermal specimens from sun-protected and from sun-exposed sites of the same individual were analyzed.
  
  
  RESULTS
  Comparison of telomere lengths revealed that the epidermis has shorter telomeres than the dermis. Telomere length in the epidermis and in the dermis was reduced with age, and average telomere shortening rates in the epidermis and in the dermis were 9 and 11 bp/yr, respectively. Unexpectedly, telomere length was not significantly different between epidermis from sun-exposed sites and from sun-protected sites.
  
  
  CONCLUSIONS
  We could not show the evidence that telomere shortening is associated with photoaging of the skin.
authors.affiliation: Research & Development Division, B&C Laboratories Inc., 132-1 Kamiizumi, Ohigawa-cho, Shida-gun, Shizuoka 421-0217, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Sugimoto
authors.forename: Ritsuo
authors.initials: R
authors.lastname: Yamashita
authors.forename: Masato
authors.initials: M
authors.lastname: Ueda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004247:DNA / Q000235:genetics / Q000378:metabolism; D020405:Dermis / Q000378:metabolism / Q000528:radiation effects / Q000648:ultrastructure; D004817:Epidermis / Q000378:metabolism / Q000528:radiation effects / Q000648:ultrastructure; D006801:Humans; D008875:Middle Aged; D010641:Phenotype; D015595:Skin Aging / Q000235:genetics* / Q000473:pathology; D016615:Telomere / Q000235:genetics* / Q000648:ultrastructure
chemical_list: D004247:DNA