title: Age-associated reduction of cell spreading induces mitochondrial DNA common deletion by oxidative stress in human skin dermal fibroblasts: implication for human skin connective tissue aging.
abstract: BACKGROUND
  Reduced cell spreading is a prominent feature of aged dermal fibroblasts in human skin in vivo. Mitochondrial DNA (mtDNA) common deletion has been reported to play a role in the human aging process, however the relationship between age-related reduced cell spreading and mtDNA common deletion has not yet been reported.
  
  
  RESULTS
  To examine mtDNA common deletion in the dermis of aged human skin, the epidermis was removed from full-thickness human skin samples using cryostat. mtDNA common deletion was significantly elevated in the dermis of both naturally aged and photoaged human skin in vivo. To examine the relationship between age-related reduced cell spreading and mtDNA common deletion, we modulated the shape of dermal fibroblasts by disrupting the actin cytoskeleton. Reduced cell spreading was associated with a higher level of mtDNA common deletion and was also accompanied by elevated levels of endogenous reactive oxygen species (ROS). Boosting cellular antioxidant capacity by using antioxidants was found to be protective against mtDNA common deletion associated with reduced cell spreading.
  
  
  CONCLUSIONS
  mtDNA common deletion is highly prevalent in the dermis of both naturally aged and photoaged human skin in vivo. mtDNA common deletion in response to reduced cell spreading is mediated, at least in part, by elevated oxidative stress in human dermal fibroblasts. These data extend current understanding of the mitochondrial theory of aging by identifying the connection between mtDNA common deletion and age-related reduction of cell spreading.
authors.affiliation: Department of Pathology, Affiliated Hospital of Yanbian University, Yanji, Jilin Province, People's Republic of China. chunjiquan@163.com.
authors.forename: Chunji
authors.initials: C
authors.lastname: Quan
authors.affiliation: Department of Dermatology, Soonchunhyang University College of Medicine, Seoul, South Korea. mkcho2001@daum.net.
authors.forename: Moon Kyun
authors.initials: MK
authors.lastname: Cho
authors.affiliation: Department of Dermatology, University of Michigan Medical School, 1301 Catherine, Medical Science I, Room 6447, Ann Arbor, MI, 48109-5609, USA. danperry@med.umich.edu.
authors.forename: Daniel
authors.initials: D
authors.lastname: Perry
authors.affiliation: Department of Dermatology, University of Michigan Medical School, 1301 Catherine, Medical Science I, Room 6447, Ann Arbor, MI, 48109-5609, USA. thquan@umich.edu.
authors.forename: Taihao
authors.initials: T
authors.lastname: Quan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism*; D020405:Dermis / Q000378:metabolism* / Q000473:pathology; D005347:Fibroblasts / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D017384:Sequence Deletion; D015595:Skin Aging
chemical_list: D004272:DNA, Mitochondrial