Hair growth promoting activity of discarded biocomposite keratin extract

J Biomater Appl. 2017 Aug;32(2):230-241. doi: 10.1177/0885328217717076. Epub 2017 Jun 29.


Keratin biomaterial has been used in regenerative medicine owing to its in-vivo and in-vitro biocompatibility. The present study was aimed to investigate the hair growth promoting activity of keratin extract and its mechanism of action. Keratin extract was topically applied on the synchronized depilated dorsal skin of telogenic C57BL/6 mice and promoted hair growth by inducing the anagen phase. The histomorphometric observation indicated significantly increases the number, shaft of hair follicles and deep subcutis area in the keratin extract treated group in contrast to the control group, which was considered an indication of anagen phase induction. Subsequently, the quantitative real-time polymerase chain reaction analysis revealed that fibroblast growth factor-10, vascular endothelial growth factor, insulin-like growth factor-1, β-catenin, and Shh were expressed earlier in the keratin extract-treated group than in the control group. Besides, keratin extract has been observed to be biocompatible when analyzed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and 4',6-diamidino-2-phenylindole staining using immortalized human keratinocyte cells, showing more than 90% cell viability. Our study demonstrated that keratin extract stimulating hair follicle growth by inducing the growth phase; anagen in telogenic C57BL/6 mice and thus the topical application of keratin extract may represent a promising biomaterial for the management and applications of hair follicle disorder.

Keywords: Keratin extract; anagen; growth factors; hair follicles; proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cell Proliferation / drug effects
  • Fibroblast Growth Factor 10 / genetics
  • Gene Expression Regulation / drug effects
  • Hair / drug effects*
  • Hair / growth & development*
  • Hair / metabolism
  • Hair Follicle / drug effects
  • Hair Follicle / growth & development
  • Hair Follicle / metabolism
  • Humans
  • Insulin-Like Growth Factor I / genetics
  • Keratinocytes / cytology
  • Keratinocytes / drug effects
  • Keratinocytes / metabolism
  • Keratins / administration & dosage
  • Keratins / isolation & purification
  • Keratins / pharmacology*
  • Mice, Inbred C57BL
  • Vascular Endothelial Growth Factor A / genetics
  • beta Catenin / genetics


  • Fibroblast Growth Factor 10
  • Vascular Endothelial Growth Factor A
  • beta Catenin
  • Insulin-Like Growth Factor I
  • Keratins