[Effect of 17-beta estradiol on the expression of receptor activator of nuclear factor kappaB ligand and osteoprotegerin of human periodontal ligament cells during their osteogenic differentiation].
OBJECTIVE
To investigate the effect of 17-beta estradiol (E(2))on the expression of receptor activator of nuclear factor kappaB ligand(RANKL) and osteoprotegerin(OPG) in human periodontal ligament cells( hPDLCs) during their osteogenic differentiation.


METHODS
hPDLCs of passage four were treated with 0.1% absolute ethyl alcohol (control), 10(-10) mol/L(physiological dose) or 10(-7) mol/L(high dose) E(2) in DMEM supplemented with 10% FBS, 10 mmol/L beta-glycerophosphate and 5 microg/mL ascorbic acid for 24 hours, 48 hours and 72 hours. Levels of RANKL and OPG mRNA were detected with real-time quantitative RT-PCR.


RESULTS
High dose E(2) induced a time-dependent decrease of RANKL mRNA and expression levels were 31.0%, 23.6% and 15.4% of the controls at 24 h, 48 h and 72 h respectively while expression levels with physiological dose E(2) were 28.4%, 87.3% and 22.6% of the controls respectively. On the other hand, E(2) increased OPG mRNA expression levels of hPDLCs which reached the maximum at 72 h with physiological dose E(2), 210.1% of the controls and with high dose E(2), 171.3% of the controls.


CONCLUSIONS
These results suggest that estrogen may exert anti-resorptive effects on alveolar bone by regulating the expression of RANKL and OPG in hPDLCs during their osteogenic differentiation.
Tang
Xiao-lin
XL
Department of Periodontology, Peking University School & Hospital of Stomatology, Beijing 100081, China.
Meng
Huan-xin
HX
Zhang
Li
L
Hou
Jian-xia
JX
Han
Jie
J
D000293:Adolescent; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D002478:Cells, Cultured; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D010012:Osteogenesis / Q000187:drug effects / Q000235:genetics; D053244:Osteoprotegerin / Q000096:biosynthesis* / Q000235:genetics; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D053245:RANK Ligand / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D004958:Estradiol