Amelogenin exons 8 and 9 encoded peptide enhances leucine rich amelogenin peptide mediated dental pulp repair.
Amelogenins containing exons 8 and 9 are alternatively spliced variants of amelogenin. Some amelogenin spliced variants have been found to promote pulp regeneration following pulp exposure. The function of the amelogenin spliced variants with the exons 8 and 9 remains unknown. In this study, we synthesized recombinant leucine rich amelogenin peptide (LRAP, A-4), LRAP plus exons 8 and 9 peptide (LRAP 8, 9) or exons 8 and 9 peptide (P89), to determine their effects on odontoblasts. In vivo analyses were completed following the insertion of agarose beads containing LRAP or LRAP 8, 9 into exposed cavity preparations of rat molars. After 8, 15 or 30 days' exposure, the pulp tissues were analyzed for changes in histomorphometry and cell proliferation by PCNA stainings. In vitro analyses included the effects of the addition of the recombinant proteins or peptide on cell proliferation, differentiation and adhesion of postnatal human dental pulp cells (DPCs). These studies showed that in vivo LRAP 8, 9 enhanced the reparative dentin formation as compared to LRAP. In vitro LRAP 8, 9 promoted DPC proliferation and differentiation to a greater extent than LRAP. These data suggest that amelogenin exons 8 and 9 may be useful in amelogenin-mediated pulp repair.
Department of Oral Medicine, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, PR China.
Yulei
Y
Huang
Michel
M
Goldberg
Thuan
T
Le
Ran
R
Qiang
Douglas
D
Warner
Halina Ewa
HE
Witkowska
Haichuan
H
Liu
Li
L
Zhu
Pamela
P
Denbesten
Wu
W
Li
D053523:Amelogenin / Q000235:genetics*; D000818:Animals; D048708:Cell Growth Processes / Q000235:genetics; D003746:Dental Enamel Proteins / Q000235:genetics*; D003782:Dental Pulp / Q000378:metabolism / Q000473:pathology / Q000502:physiology*; D004195:Disease Models, Animal; D005091:Exons; D006801:Humans; D008297:Male; D009804:Odontoblasts / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D053523:Amelogenin; D003746:Dental Enamel Proteins; C067432:leucine-rich amelogenin peptide