Abstract
Introduction
The lysyl oxidase (LOX) family is an emerging family of amine oxidases responsible
for the formation of collagen fibrils in the extracellular matrix. To date, 5 LOX family genes have been identified in humans, encoding LOX and LOX-like proteins (LOXL,
LOXL2, LOXL3, and LOXL4). The goal of this study was to evaluate the expression and
function of the LOX family genes in odontoblastic differentiation of human dental pulp (HDP) cells.
Methods
Expression of the LOX family genes was assessed by reverse transcriptase polymerase chain reaction analysis,
and the amine oxidase activity of HDP cells was evaluated by peroxidase-coupled fluorometric
assays. Mineral nodule formation and expression of odontoblastic marker genes were
assessed in the presence and absence of specific small interfering RNAs (siRNAs) of
the LOX family genes.
Results
Among the LOX family genes, only LOX and LOXL showed prominent expression during odontoblastic differentiation of HDP cells. Suppression
of LOX and LOXL expression by siRNA-induced interference substantially decreased the amine oxidase
activity of the differentiating HDP cells. Furthermore, interference of LOX and LOXL expression inhibited mineral nodule formation and expression of odontoblastic marker
genes during odontoblastic differentiation of HDP cells.
Conclusions
These findings show for the first time that the LOX- and LOXL-mediated organization
of collagen fibrils in extracellular matrices of HDP cells might be an important regulator
for odontoblastic differentiation of HDP cells.
Key Words
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Article info
Publication history
Published online: April 23, 2012
Footnotes
Eun-Cheol Kim and Hwa-Jeong Lee contributed equally to this work.
Supported by the Korea Research Foundation Grant (KRF-2008-314-E00205) funded by the Korean Government (MOEHRD).
Identification
Copyright
© 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
