title: A new lipophilic pro-vitamin C, tetra-isopalmitoyl ascorbic acid (VC-IP), prevents UV-induced skin pigmentation through its anti-oxidative properties.
abstract: BACKGROUND
  Vitamin C, which is a strong anti-oxidant, plays an important role in maintaining physiological states. In dermatology, Vitamin C is used for treatment of various skin problems such as de-pigmentation of hyperpigmented spots. However, Vitamin C has limited stability and permeability, and development of a Vitamin C derivative with improved properties is needed.
  
  
  OBJECTIVE
  We evaluated the effect of a lipophilic Vitamin C derivative, tetra-isopalmitoyl ascorbic acid (VC-IP), on ultraviolet (UV)-induced skin pigmentation, to determine its potential as a more effective form of Vitamin C.
  
  
  METHODS
  The release of Vitamin C from VC-IP was examined using a reconstructed skin model following topical application of VC-IP. Anti-oxidative and anti-inflammatory activities of VC-IP were tested in cultured human keratinocytes. Subsequently, clinical test was done to clarify the effect of VC-IP on UVB-induced skin pigmentation.
  
  
  RESULTS
  VC-IP released Vitamin C in physiological conditions and worked as pro-Vitamin C. In subsequent experiments, we found that VC-IP suppressed the elevation of intracellular peroxide after UVB irradiation, and enhanced cellular tolerance against UVB and reactive oxygen species such as hydrogen peroxide and tert-butyl hydroperoxide. Furthermore, VC-IP reduced the production of interleukin-1alpha and prostaglandin E2 in UVB-irradiated keratinocytes and suppressed melanocyte proliferation in conditioned culture medium prepared from UVB-irradiated keratinocytes. Finally, in a clinical study, topical application of a 3% VC-IP cream for 3 weeks suppressed pigmentation after UVB irradiation.
  
  
  CONCLUSIONS
  These results demonstrate that VC-IP is a precursor of Vitamin C, and effectively suppresses UVB-induced skin pigmentation, possibly through its anti-oxidative activity.
authors.affiliation: Cosmos Technical Center Co., Ltd., 3-24-3, Hasune, Itabashi-Ku, Tokyo 174-0046, Japan. ochiai@ns-cosmos.co.jp
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Ochiai
authors.forename: Satoko
authors.initials: S
authors.lastname: Kaburagi
authors.forename: Kei
authors.initials: K
authors.lastname: Obayashi
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Ujiie
authors.forename: Satoru
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Yuri
authors.initials: Y
authors.lastname: Okano
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Masaki
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Ichihashi
authors.forename: Hiromu
authors.initials: H
authors.lastname: Sakurai
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics; D002455:Cell Division; D002461:Cell Line, Transformed; D015232:Dinoprostone / Q000378:metabolism; D005260:Female; D006017:Glycolipids / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D006801:Humans; D053582:Interleukin-1alpha / Q000378:metabolism; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000528:radiation effects; D008297:Male; D008544:Melanocytes / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D018384:Oxidative Stress / Q000187:drug effects; D012880:Skin Pigmentation / Q000187:drug effects* / Q000528:radiation effects; D013400:Sugar Acids; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D006017:Glycolipids; D053582:Interleukin-1alpha; D013400:Sugar Acids; C515144:tetra-isopalmitoyl ascorbic acid; C011491:provitamin C; D015232:Dinoprostone; D001205:Ascorbic Acid