[Effects of parathyroid hormone on osteoprotegerin expression and osteoprotegerin ligand and their related cytokines in human osteoblasts].
OBJECTIVE
To investigate the pathway and mechanism of parathyroid hormone (PTH) in regulating bone resorption.


METHODS
We observed the regulative effects of PTH on the expression of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) and their related cytokines (M-CSF and TRAIL) in human osteoblasts (HOBs). The expressions of OPG, OPGL, M-CSF, and TRAIL mRNA were determined by RT-PCR. The expressions of OPG and OPGL proteins were measured by Western blotting.


RESULTS
PTH down-regulated the expression of OPG but up-regulated the expressions of OPGL, M-CSF and TRAIL in HOBs.


CONCLUSIONS
PTH can promote the bone resorption by decreasing the expression of OPG, increasing the expressions of some bone-resorbing cytokines such as OPGL, M-CSF, and TRAIL in osteoblasts, and then stimulating the osteoclast differentiation and activity.
Su
Xin
X
Institute of Endocrinology and Metabolism, Second Xiangya Hospital, Central South University, Changsha 410011, China. suxin@21cn.com
Liao
Er-yuan
EY
Peng
Jian
J
Liu
Shi-ping
SP
Dai
Ru-chun
RC
D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D016173:Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000235:genetics; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D053244:Osteoprotegerin / Q000096:biosynthesis* / Q000235:genetics; D010281:Parathyroid Hormone / Q000494:pharmacology*; D053245:RANK Ligand / Q000096:biosynthesis* / Q000235:genetics; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000096:biosynthesis / Q000235:genetics
D016207:Cytokines; D053244:Osteoprotegerin; C470125:PTH protein, human; D010281:Parathyroid Hormone; D053245:RANK Ligand; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D016173:Macrophage Colony-Stimulating Factor