title: Improvement of naturally aged skin with vitamin A (retinol).
abstract: OBJECTIVE
  To evaluate the effectiveness of topical retinol (vitamin A) in improving the clinical signs of naturally aged skin.
  
  
  METHODS
  Randomized, double-blind, vehicle-controlled, left and right arm comparison study.
  
  
  METHODS
  Academic referral center.
  
  
  METHODS
  The study population comprised 36 elderly subjects (mean age, 87 years), residing in 2 senior citizen facilities.
  
  
  METHODS
  Topical 0.4% retinol lotion or its vehicle was applied at each visit by study personnel to either the right or the left arm, up to 3 times a week for 24 weeks.
  
  
  METHODS
  Clinical assessment using a semiquantitative scale (0, none; 9, most severe) and biochemical measurements from skin biopsy specimens obtained from treated areas.
  
  
  RESULTS
  After 24 weeks, an intent-to-treat analysis using the last-observation-carried-forward method revealed that there were significant differences between retinol-treated and vehicle-treated skin for changes in fine wrinkling scores (-1.64 [95% CI, -2.06 to -1.22] vs -0.08 [95% CI, -0.17 to 0.01]; P<.001). As measured in a subgroup, retinol treatment significantly increased glycosaminoglycan expression (P = .02 [n = 6]) and procollagen I immunostaining (P = .049 [n = 4]) compared with vehicle.
  
  
  CONCLUSIONS
  Topical retinol improves fine wrinkles associated with natural aging. Significant induction of glycosaminoglycan, which is known to retain substantial water, and increased collagen production are most likely responsible for wrinkle effacement. With greater skin matrix synthesis, retinol-treated aged skin is more likely to withstand skin injury and ulcer formation along with improved appearance.
authors.affiliation: Department of Dermatology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
authors.forename: Reza
authors.initials: R
authors.lastname: Kafi
authors.forename: Heh Shin R
authors.initials: HS
authors.lastname: Kwak
authors.forename: Wendy E
authors.initials: WE
authors.lastname: Schumacher
authors.forename: Soyun
authors.initials: S
authors.lastname: Cho
authors.forename: Valerie N
authors.initials: VN
authors.lastname: Hanft
authors.forename: Ted A
authors.initials: TA
authors.lastname: Hamilton
authors.forename: Anya L
authors.initials: AL
authors.lastname: King
authors.forename: Jacqueline D
authors.initials: JD
authors.lastname: Neal
authors.forename: James
authors.initials: J
authors.lastname: Varani
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Fisher
authors.forename: John J
authors.initials: JJ
authors.lastname: Voorhees
authors.forename: Sewon
authors.initials: S
authors.lastname: Kang
mesh_terms: D000279:Administration, Cutaneous; D000369:Aged, 80 and over; D001284:Atrophy / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D004311:Double-Blind Method; D005260:Female; D006025:Glycosaminoglycans / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000235:genetics / Q000378:metabolism; D015595:Skin Aging / Q000187:drug effects* / Q000473:pathology / Q000502:physiology; D016896:Treatment Outcome; D014801:Vitamin A / Q000008:administration & dosage*; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D024042:Collagen Type I; D006025:Glycosaminoglycans; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D014815:Vitamins; C082928:retinoic acid binding protein II, cellular; D014801:Vitamin A