Androgen induction of follicular epithelial cell growth is mediated via insulin-like growth factor-I from dermal papilla cells.
Androgen significantly stimulates the proliferation of outer root sheath cells that are cocultured with beard dermal papilla cells without cell contact. The expression of insulin-like growth factor I (IGF-I) mRNA in beard dermal papilla cells was stimulated by androgen and antagonized by cyproterone acetate. Outer root sheath cells did not express mRNA for IGF-I either in the presence or absence of androgen. Both of these two types of cells expressed mRNA for IGF-I receptor and the expression was not affected by androgen. Neutralizing antibody against IGF-I antagonized the stimulatory effect of androgen on the growth of outer root sheath cell cocultured with beard dermal papilla cells. These findings suggest that IGF-I is a candidate for androgen induced hair growth factors.
Itami
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Department of Dermatology, Oita Medical University, Japan.
Kurata
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Takayasu
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D000906:Antibodies; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D017373:Cyproterone Acetate / Q000494:pharmacology; D017931:DNA Primers / Q000235:genetics; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006197:Hair / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015741:Metribolone / Q000494:pharmacology*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D000906:Antibodies; D017931:DNA Primers; D012333:RNA, Messenger; D015741:Metribolone; D017373:Cyproterone Acetate; D007334:Insulin-Like Growth Factor I