[Effects of 1,25-dihydroxyvitamin D3 on the expressions of osteoprotegerin and receptor activator of NF-kappaB ligand in mouse osteoblasts].
OBJECTIVE
To study the effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on the expression of osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) mRNA in mouse osteoblasts.


METHODS
Calvariae derived from CD-1 neonatal mouse (after born 24 h). Bone samples were processed by the collagenase/trypsin digestion method. Mouse osteoblasts were cultured in vitro. After 48 hours of addition of 1,25(OH)2D3 (0, 10(-8), 10(-9), 10(-11) mol/L) to the culture medium of mouse osteoblasts, the content of the OPG protein in culture medium was estimated with enzyme linked immunosorbent assay. Total RNA was prepared from mouse osteoblasts. mRNA expression of OPG and RANKL were detected by reverse transcription-polymerase chain reaction.


RESULTS
The mRNA expression of OPG in osteoblasts added with 1,25(OH)2D3 significantly decreased compared with the controls, which was markedly dose-dependent. OPG protein production in the medium decreased after treatment with 1,25(OH)2D3. In contrast, RANKL mRNA expression levels in osteoblasts significantly increased after 48 h of culture with 1,25(OH)2D3.


CONCLUSIONS
1,25 (OH)2D3 can stimulate RANKL mRNA expression, but decrease OPG mRNA levels in vitro in mouse osteoblasts.
Tian
Qing-xian
QX
Doctorate Candidate of Clinical Medicine in the 2001 Grade, Peking Union Medical College, Beijing 100730, China. tqxian@sohu.com
Huang
Gong-yi
GY
D000818:Animals; D000831:Animals, Newborn; D002117:Calcitriol / Q000494:pharmacology*; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D006023:Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D008024:Ligands; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D016328:NF-kappa B / Q000096:biosynthesis / Q000235:genetics; D010010:Osteoclasts / Q000378:metabolism* / Q000502:physiology; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics
D002352:Carrier Proteins; D006023:Glycoproteins; D008024:Ligands; D008562:Membrane Glycoproteins; D016328:NF-kappa B; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505687:Tnfrsf11a protein, mouse; C506031:Tnfrsf11b protein, mouse; C505689:Tnfsf11 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D002117:Calcitriol