Effects of human full-length amelogenin on the proliferation of human mesenchymal stem cells derived from bone marrow.
Amelogenins are enamel matrix proteins that play a crucial role in enamel formation. Recent studies have revealed that amelogenins also have cell signaling properties. Although amelogenins had been described as specific products of ameloblasts, recent research has demonstrated their expression in bone marrow stromal cells. In this study, we examined the effect of recombinant human full-length amelogenin (rh174) on the proliferation of human mesenchymal stem cells (MSCs) derived from bone marrow and characterized the associated changes in intracellular signaling pathways. MSCs were treated with rh174 ranging in dose from 0 to 1,000 ng/ml. Cell proliferative activity was analyzed by bromodeoxyuridine (BrdU) immunoassay. The expression of lysosomal-associated membrane protein 1 (LAMP1), a possible amelogenin receptor, in MSCs was analyzed. Anti-LAMP1 antibody was used to block the binding of rh174 to LAMP1. The MAPK-ERK pathway was examined by Cellular Activation of Signaling ELISA (CASE) kit and western blot analysis. A specific MAPK inhibitor, U0126, was used to block ERK activity. It was shown that rh174 increased the proliferation of MSCs and MAPK-ERK activity. The MSC proliferation and MAPK-ERK activity enhanced by rh174 were reduced by the addition of anti-LAMP1 antibody. Additionally, the increased proliferation of MSCs induced by rh174 was inhibited in the presence of U0126. In conclusion, it is demonstrated that rh174 increases the proliferation of MSCs by interaction with LAMP1 through the MAPK-ERK signaling pathway, indicating the possibility of MSC application to tissue regeneration in the orofacial region.
Huang
Yu-Ching
YC
Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan.
Tanimoto
Kotaro
K
Tanne
Yuki
Y
Kamiya
Takashi
T
Kunimatsu
Ryo
R
Michida
Masahiko
M
Yoshioka
Motoko
M
Yoshimi
Yuki
Y
Kato
Yukio
Y
Tanne
Kazuo
K
D001854:Bone Marrow Cells / Q000166:cytology; D002070:Butadienes / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D003746:Dental Enamel Proteins / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D051907:Lysosomal Membrane Proteins / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D011994:Recombinant Proteins; D012038:Regeneration; D015398:Signal Transduction; D052118:Lysosomal-Associated Membrane Protein 1
D002070:Butadienes; D003746:Dental Enamel Proteins; D004791:Enzyme Inhibitors; D051907:Lysosomal Membrane Proteins; D020929:Mitogen-Activated Protein Kinase Kinases; D009570:Nitriles; D011994:Recombinant Proteins; C507067:AMTN protein, human; C489116:LAMP1 protein, human; D052118:Lysosomal-Associated Membrane Protein 1; C113580:U 0126