title: Exogenous IGF-1 promotes hair growth by stimulating cell proliferation and down regulating TGF-β1 in C57BL/6 mice in vivo.
abstract: OBJECTIVE
  Insulin-like growth factor 1 (IGF-1) increases the growth of cultured hair follicles and plays a role in regulating hair migration during the development of hair follicles in transgenic mice. However, the exogenous effect of IGF-1 on hair growth in wild-type mice has not been reported. In the present study, we examined whether IGF-1 was an important regulator of hair follicle growth in wide-type mice in vivo.
  
  
  METHODS
  C57BL/6 mice were injected with different concentrations of IGF-1 on dorsal skin. The treated tissues were analyzed by immunoassay methods for TGF-β1 and BrdU.
  
  
  RESULTS
  Local injection of IGF-1 increased hair follicle number and prolonged the growing phase during the transition from anagen to telogen. Meanwhile, immunology analyses revealed that IGF-1 also stimulated the proliferation of follicle cells in anagen of the matrix and down regulated TGF-β1 expression in hair follicles.
  
  
  CONCLUSIONS
  These observations suggest that IGF-1 is an effective stimulator of hair follicle development in wide-type mice in vivo and may be a promising drug candidate for baldness therapy.
authors.affiliation: Department of Food Science and Technology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Jingjie
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Life Science, Huzhou University, Huzhou, Zhejiang 31300, PR China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Food Science and Technology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Food Science and Technology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Gu
authors.affiliation: Department of Food Science and Technology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Yunbo
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Food Science and Technology, Chungnam National University, Daejeon 305-764, Republic of Korea. Electronic address: kchsung@cnu.ac.kr.
authors.forename: Changkeun
authors.initials: C
authors.lastname: Sung
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects*; D015536:Down-Regulation / Q000187:drug effects; D006197:Hair / Q000187:drug effects* / Q000254:growth & development*; D018859:Hair Follicle / Q000187:drug effects / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
chemical_list: D053773:Transforming Growth Factor beta1; D007334:Insulin-Like Growth Factor I
keywords: Black pigmentation; BrdU; Cell proliferation; IGF- 1; TGF-β1; Wild-type mouse