LS8 cell apoptosis induced by NaF through p-ERK and p-JNK - a mechanism study of dental fluorosis.
OBJECTIVE
To investigate the possible biological mechanism of dental fluorosis at a molecular level.


METHODS
Cultured LS8 were incubated with serum-free medium containing selected concentrations of NaF (0 ∼ 2 mM) for either 24 or 48 h. Subcellular microanatomy was characterized using TEM; meanwhile, selected biomolecules were analysed using various biochemistry techniques. Transient transfection was used to modulate a molecular pathway for apoptosis.


RESULTS
Apoptosis of LS8 was induced by NaF treatment that showed both time and concentration dependency. The activity of caspase-3, -8, -9 was found to be increased with NaF in a dose-dependent manner. Western blot revealed that the protein expression of p-ERK and p-JNK were decreased, while the expression of p-P38 was increased. Inhibition of the p-ERK and p-JNK pathways resulted in a similar decrease for caspase-3.


CONCLUSIONS
During NaF-induced apoptosis of LS8, p-ERK and p-JNK were closely associated with induction of apoptosis, which might be a mechanism of dental fluorosis.
a Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, Department of Preventive Dentistry , Stomatology Hospital, Xi'an Jiaotong University , Xi'an , PR China.|b Department of Oral Pathology, Stomatology Hospital, Ningxia Medical University , Yinchuan , PR China.
Lin
L
Zhao
a Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, Department of Preventive Dentistry , Stomatology Hospital, Xi'an Jiaotong University , Xi'an , PR China.
Juedan
J
Li
a Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, Department of Preventive Dentistry , Stomatology Hospital, Xi'an Jiaotong University , Xi'an , PR China.|d Department of Endodontics, Yinchuan Stomatology Hospital , Yinchuan , PR China.
Jiali
J
Su
c Herman Ostrow School of Dentistry of USC, Center for Craniofacial Molecular Biology , University of Southern California , Los Angeles , CA , USA.
Malcolm L
ML
Snead
a Clinical Research Center of Shaanxi Province for Dental and Maxillofacial Diseases, Department of Preventive Dentistry , Stomatology Hospital, Xi'an Jiaotong University , Xi'an , PR China.
Jianping
J
Ruan
D000565:Ameloblasts / Q000187:drug effects* / Q000648:ultrastructure; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002327:Cariostatic Agents / Q000009:adverse effects*; D053148:Caspase 3 / Q000187:drug effects; D053181:Caspase 8; D053453:Caspase 9; D018929:Cell Culture Techniques; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D048049:Extracellular Signal-Regulated MAP Kinases / Q000187:drug effects; D009050:Fluorosis, Dental / Q000201:enzymology / Q000209:etiology*; D020868:Gene Silencing; D048031:JNK Mitogen-Activated Protein Kinases / Q000187:drug effects; D020935:MAP Kinase Signaling System / Q000187:drug effects; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000187:drug effects*; D034741:RNA, Small Interfering / Q000235:genetics; D012969:Sodium Fluoride / Q000009:adverse effects*; D014162:Transfection; D048051:p38 Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000235:genetics
D002327:Cariostatic Agents; D034741:RNA, Small Interfering; D012969:Sodium Fluoride; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C505409:Casp3 protein, mouse; C505526:Casp8 protein, mouse; C506434:Casp9 protein, mouse; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9
LS8; NaF; apoptosis; dental fluorosis; mitogen-activated protein kinase