title: The topical penta-peptide Gly-Pro-Ile-Gly-Ser increases the proportion of thick hair in Japanese men with androgenetic alopecia.
abstract: BACKGROUND
  A penta-peptide, Gly-Pro-Ile-Gly-Ser (GPIGS), promotes proliferation of mouse hair keratinocytes and accelerates hair growth in mice.
  
  
  OBJECTIVE
  This study focused on the ability of the peptide to promote human hair growth.
  
  
  METHODS
  We used a human hair keratinocyte proliferation assay and organ cultures of human hair follicle as in vitro systems. The lotions with and without the penta-peptide were administered to 22 Japanese men with androgenetic alopecia (AGA) for 4 months in a double-blind and randomized clinical study.
  
  
  RESULTS
  The penta-peptide significantly stimulated the proliferation of human hair keratinocytes at a concentration of 2.3 μm (P < 0.01), and 5.0 μm of this peptide had a marked effect on hair shaft elongation in the organ culture (P < 0.05). The change in the proportion of thick hair (≥60 μm) compared to baseline in patients that received the peptide was significantly higher than in the placebo (P = 0.006). The change in the proportion of vellus hair (<40 μm) was also significantly lower in the peptide group than in the placebo (P = 0.029). The penta-peptide also significantly improved the appearance of baldness (P = 0.020) when blinded reviewers graded photographs of the participants according to a standardized baldness scale. No adverse dermatological effects due to treatment were noted during this clinical study.
  
  
  CONCLUSIONS
  This penta-peptide promotes proliferation of human hair keratinocytes and hair shaft elongation of human hair follicles, in vitro. This peptide increases thick hair ratio in vivo, and this compound is useful for the improvement of AGA.
authors.affiliation: Shiseido Global Innovation Center, Hayabuchi, Tsuzuki, Yokohama, Japan.
authors.forename: Tokuro
authors.initials: T
authors.lastname: Iwabuchi
authors.affiliation: Shiseido Global Innovation Center, Hayabuchi, Tsuzuki, Yokohama, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Takeda
authors.affiliation: Shiseido Global Innovation Center, Hayabuchi, Tsuzuki, Yokohama, Japan.
authors.forename: Haruyo
authors.initials: H
authors.lastname: Yamanishi
authors.affiliation: Shiseido Global Innovation Center, Hayabuchi, Tsuzuki, Yokohama, Japan.
authors.forename: Ritsuro
authors.initials: R
authors.lastname: Ideta
authors.affiliation: Shiseido Global Innovation Center, Hayabuchi, Tsuzuki, Yokohama, Japan.
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Ehama
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Central 6, Tsukuba, Ibaraki, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Tsuruda
authors.affiliation: Frontier Technology Laboratory, Inc., Minato-ku, Tokyo, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Shibata
authors.affiliation: Frontier Technology Laboratory, Inc., Minato-ku, Tokyo, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ito
authors.affiliation: Frontier Technology Laboratory, Inc., Minato-ku, Tokyo, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Komatsu
authors.affiliation: Keiyu Hospital, Hiyoshi, Kohku-ku, Yokohama, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Terai
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Central 6, Tsukuba, Ibaraki, Japan.
authors.forename: Syuichi
authors.initials: S
authors.lastname: Oka
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000505:Alopecia / Q000175:diagnosis / Q000188:drug therapy*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004151:Dipeptides / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005500:Follow-Up Studies; D006197:Hair / Q000254:growth & development*; D018859:Hair Follicle / Q000187:drug effects* / Q000254:growth & development; D006801:Humans; D007564:Japan; D015603:Keratinocytes / Q000187:drug effects / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides / Q000008:administration & dosage; D009844:Oligosaccharides / Q000627:therapeutic use*; D012016:Reference Values; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D004151:Dipeptides; D009842:Oligopeptides; D009844:Oligosaccharides; C064764:PENTA; C061903:glycyl-glycyl-proline; C015248:glycylproline
keywords: androgenetic alopecia; hair growth; hair keratinocyte; penta-peptide