[Differential expression of osteopontin and bax, bcl-2 by fluoride].
OBJECTIVE
To study the differential expression of bax, bcl-2 and osteopontin by fluoride in the renal tubular cells in vitro.


METHODS
The renal tubular cells were cultured and exposed to sodium fluoride (NaF) in 1, 5, 7.5, 12.5 mg F-/L level. The transcription level of bax, bcl-2 and osteopontin were investigated by reverse transcription - polymerase chain reaction (RT-PCR).


RESULTS
The expression of bax mRNA in 7.5 and 12.5 mgF-/L groups (optical absorption ratio value was 2.37 +/- 0.18 and 2.64 +/- 0.19 respectively) was significantly increased (P < 0.01). On the contrary, the level of bcl-2 obviously decreased (5 mg F-/L group optical absorption ratio value, 0.80 +/- 0.22, P < 0.05; 7.5 mg F-/L group optical absorption ratio value 0.71 +/- 0.22, P < 0.01). The expression mRNA of osteopontin was significantly increased when cells were exposed to fluoride at 7.5 mg F-/L (optical absorption ratio value 2.01 +/- 0.40 P < 0.01), in that group the tubular cell apoptotic trend was obvious.


CONCLUSIONS
NaF might induce tubular cell apoptosis via activation of bax expression and bcl-2 suppression. Osteopontin might protect the tubule against apoptosis in a lower fluoride level, but the function should be decreased in higher fluoride level.
Xu
Hui
H
Department of Pathology, Institute of Frontier Medical Science, Jilin University, Changchun 130021, China.
Zhang
Jing-min
JM
Zhang
Xiu-yun
XY
Li
Guang-sheng
GS
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D051017:Apoptosis Regulatory Proteins / Q000235:genetics; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D020869:Gene Expression Profiling; D007684:Kidney Tubules / Q000166:cytology; D008297:Male; D053495:Osteopontin / Q000235:genetics*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012969:Sodium Fluoride / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein / Q000235:genetics*
D051017:Apoptosis Regulatory Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; D053495:Osteopontin; D012969:Sodium Fluoride