Odontoclastogenesis of mouse papilla-derived MDPC-23 cells induced by lipopolysaccharide.
OBJECTIVE
To investigate the role of Lipopolysaccharide (LPS) in the odontoclast differentiation of MDPC-23 cells. It was hypothesized that MDPC-23 odontoblast-like cells may function as odontoclasts under the influence of LPS.


METHODS
MDPC-23 cells were cultured in the presence of 0.1 or 1 μg mL-1LPS for 6 days. Cell viability was determined using the CCK8 assay. TRAP staining, dentine resorption assay and ROS detection by confocal laser scanning microscope were used to test the odontoclast-like function of the induced cells. In additional, the related protein expression was confirmed by Western blotting and ELISA. An unpaired Student's t-test and one-way anova were used in statistical analysis.


RESULTS
TRAP-positive cells, which are multinucleated, on the dentine slice were significantly increased in 1 μg mL-1LPS-induced cells (P < 0.05). Osteoclast-specific proteins such as TRAP cathepsin K and Rac1 were upregulated in the 1 μg mL-1LPS-treated cells (P < 0.05), whilst the expression of marker proteins of the RANKL-RANK signalling pathway (RANKL, RANK and TRAF6) in the induced cells was not significantly changed (P > 0.05). ROS production was observed in the 1 μg mL-1LPS treatment group (P < 0.05), but no significant differences were observed in the level of RANKL in the cell supernatant between the LPS-treated group and the control group (P > 0.05).


CONCLUSIONS
A known value of 1 μg mL-1LPS might induce odontoblast-like MDPC-23 cells to generate odontoclast-like cells or to function as odontoclasts. The data might provide a new explanation for the precursors of odontoclasts and root resorption.
Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Affiliated Stomatological Hospital, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China.
C
C
Li
Key Laboratory of Oral Medicine, Guangzhou Institute of Oral Disease, Stomatology Hospital of Guangzhou Medical University, Guangzhou, China.
W T
WT
Qi
Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Affiliated Stomatological Hospital, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China.
H W
http://orcid.org/0000-0002-2351-9986
HW
Jiang
D000818:Animals; D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D003771:Dental Papilla / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051379:Mice; D018613:Microscopy, Confocal; D009805:Odontogenesis / Q000187:drug effects*; D010010:Osteoclasts / Q000187:drug effects / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
D008070:Lipopolysaccharides; D017382:Reactive Oxygen Species
RANKL-RANK signalling pathway; lipopolysaccharide; odontoclast; osteoclast