Activin A induces terminal differentiation of cultured human keratinocytes.
Activin A, a member of the TGFbeta-superfamily, is well known to play important roles in the growth and differentiation of various target cells. We have previously demonstrated that activin A is produced at an early stage of cultivation at both the protein and the mRNA levels in cultured human keratinocytes. In this study, the effects of activin A on differentiation and proliferation of human keratinocytes were examined. Activin A (> or =1 nM) induced cornified envelope formation and the synthesis of loricrin, keratin 1, involucrin, and transglutaminase 1. In addition, transglutaminase activity and mRNA level of transglutaminase 1 were increased by activin A. [3H]Thymidine incorporation and cell number were reduced by activin A (> or =1 nM) compared with control, suggesting an inhibitory effect of activin A on cell proliferation. On the basis of these findings, it is likely that activin A contributes to differentiation and suppression of proliferation in human keratinocytes.
Seishima
M
M
Department of Dermatology, Gifu University School of Medicine, Japan.
Nojiri
M
M
Esaki
C
C
Yoneda
K
K
Eto
Y
Y
Kitajima
Y
Y
D028341:Activins; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007265:Inhibins / Q000494:pharmacology*; D015603:Keratinocytes / Q000187:drug effects*
D028341:Activins; D007265:Inhibins