title: Effects of long-pulsed 1,064-nm neodymium-doped yttrium aluminum garnet laser on dermal collagen remodeling in hairless mice.
abstract: BACKGROUND
  Nonablative lasers are used for dermal collagen remodeling. Although clinical improvements have been reported using various laser devices, the mechanism of dermal collagen remodeling remains unknown.
  
  
  OBJECTIVE
  To investigate the effects of energy fluences of the long-pulsed neodymium-doped yttrium aluminum garnet (Nd:YAG) nonablative laser on dermal collagen remodeling and evaluate the dermal collagen remodeling mechanism.
  
  
  METHODS
  Hairless mice were pretreated with ultraviolet B irradiation to produce photo-damage. The laser treatment used a long-pulse 1,064-nm Nd:YAG laser at energy fluences of 20, 40, and 60 J/cm(2) . The amount of dermal collagen and expressions of transforming growth factor beta (TGF-β), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinase-1 (TIMP-1) of laser treated skin were compared with those of nontreated control skin.
  
  
  RESULTS
  The long-pulse Nd:YAG laser treatment increased dermal collagen and significantly increased TGF-β expression. The expression of MMP-1 decreased with low energy fluence. The expression of TIMP-1 was not significantly different.
  
  
  CONCLUSIONS
  Long-pulsed 1,064-nm Nd:YAG laser increases the dermal collagen in association with the increased expression of TGF-β.
authors.affiliation: Department of Dermatology, Yeouido St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, Korea.
authors.forename: Young Bok
authors.initials: YB
authors.lastname: Lee
authors.forename: Na Hyeon
authors.initials: NH
authors.lastname: Kang
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Eun
authors.forename: Min Seok
authors.initials: MS
authors.lastname: Cheon
authors.forename: Kyung Moon
authors.initials: KM
authors.lastname: Kim
authors.forename: Baik Kee
authors.initials: BK
authors.lastname: Cho
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Park
mesh_terms: D000818:Animals; D003094:Collagen / Q000378:metabolism / Q000528:radiation effects*; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008812:Mice, Hairless; D023421:Models, Animal; D012333:RNA, Messenger / Q000378:metabolism; D012060:Rejuvenation; D012867:Skin / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D015595:Skin Aging / Q000473:pathology / Q000528:radiation effects*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D014466:Ultraviolet Rays / Q000009:adverse effects
chemical_list: D012333:RNA, Messenger; D019715:Tissue Inhibitor of Metalloproteinase-1; D016212:Transforming Growth Factor beta; D003094:Collagen; D020781:Matrix Metalloproteinase 1