Endoplasmic reticulum stress and mineralization inhibition mechanism by the resinous monomer HEMA.
OBJECTIVE
To investigate the expression of two endoplasmic reticulum (ER)-resident key chaperone proteins, ERdj5 and BiP, under the influence of resinous monomers and its relationship with the inhibition of mineralization caused by the monomer 2-hydroxyethyl methacrylate (HEMA).


METHODS
The ERdj5 and BiP expression was studied in vitro, in primary human pulp cell cultures after treatment with three different HEMA concentrations at different time periods. Subsequently, the expression of both the odontoblast markers dentine sialoprotein (DSP) and osteonectin (OSN) was studied in human pulp cells under the same conditions.


RESULTS
The ERdj5 and BiP expression was upregulated in the pulp cells. DSP and OSN were largely dispersed in the cytoplasm in control cell cultures but accumulated in a perinuclear area after exposure to HEMA. Their expression levels were not affected.


CONCLUSIONS
The increased expression of ERdj5 and BiP may reflect activation of ER stress. DSP and OSN accumulation into the cells may lead to their secretion arrest and inhibition of dentine matrix formation. These events may elucidate the mechanism by which HEMA inhibits the mineralization process.
Departments of Endodontics and Basic Sciences, Dental School, University of Athens, Athens, Greece. ediamanti@dent.uoa.gr
E
E
Diamanti
S
S
Mathieu
C
C
Jeanneau
E
E
Kitraki
P
P
Panopoulos
G
G
Spyrou
I
I
About
D000293:Adolescent; D002478:Cells, Cultured; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects*; D003799:Dental Stress Analysis; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress; D005109:Extracellular Matrix / Q000187:drug effects; D016326:Extracellular Matrix Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D050956:HSP40 Heat-Shock Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D008689:Methacrylates / Q000009:adverse effects*; D018832:Molecular Chaperones / Q000378:metabolism*; D009804:Odontoblasts / Q000187:drug effects* / Q000378:metabolism; D015676:Osteonectin / Q000037:antagonists & inhibitors / Q000378:metabolism; D010750:Phosphoproteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D012795:Sialoglycoproteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D013312:Stress, Physiological; D014074:Tooth Calcification / Q000187:drug effects*; D000099311:Dentin Sialophosphoprotein
D000091342:Endoplasmic Reticulum Chaperone BiP; D016326:Extracellular Matrix Proteins; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D008689:Methacrylates; D018832:Molecular Chaperones; D015676:Osteonectin; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C530517:ERdj5 protein, mouse; C005044:hydroxyethyl methacrylate