Volume 48, Issue 4 , Pages 350-355, December 2009
Effect of Estrogen on the Activity and Growth of Human Osteoclasts In Vitro
Article Outline
Summary
Objective
Estrogen deficiency results in postmenopausal osteoporosis by increasing the rate of bone loss. The mechanism responsible for the effects of estrogen on osteoclasts is still unclear.
Materials and Methods
The potential of mononuclear cells from cord blood or bone marrow to differentiate into mature osteoclasts when co-cultured with human osteoblast cells was investigated. The effects of estrogen on osteoclastogenesis and osteoclast activity were also examined.
Results
Macrophage markers CD11b and CD14 were downregulated and vitronectin receptor was upregulated during 28 days' co-culture of mononuclear cells and human osteoblasts. Long-term co-culture resulted in the formation of numerous large tartrate-resistant acid phosphatase-positive multinucleated cells capable of resorption of bone slices. After incubation for 28 days, the addition of 17β-estradiol caused a significant decrease in the expression of vitronectin receptor and tartrate-resistant acid phosphatase-positive multinucleated cells in cultures derived from both bone marrow and cord blood. A significant decrease in bone resorption was also noted in the presence of estrogen.
Conclusion
Estrogen not only suppresses osteoclastogenesis but also inhibits the activity of osteoclasts.
Key Words: bone marrow , cord blood , osteoblast , postmenopausal osteoporosis
No full text is available. To read the body of this article, please view the PDF online.
References
- . Estrogen promotes apoptosis of murine osteoclasts mediated by TGF-β . Nat Med . 1996;2:1132–1136
- Mammalian mature osteoclasts as estrogen target cells . Biochem Biophys Res Commun . 1996;223:637–642
- . The effect of sex hormones on bone resorption by rat osteoclasts . Acta Endocrinol (Copenh) . 1991;124:121–127
- . Cytokines and estrogen in bone: anti-osteoporotic effects . Science . 1993;260:626–627
- . Bone marrow, cytokines, and bone remodeling: emerging insights into the pathophysiology of osteoporosis . N Engl J Med . 1995;332:305–311
- . Estrogen, cytokines, and pathogenesis of post-menopausal osteoporosis . J Bone Miner Res . 1996;8:1043–1051
- . Skeletal effects of estrogen . Endocr Rev . 1994;15:275–300
- . Cell biology of the osteoclast . Exp Hematol . 1999;27:1229–1241
- . The functional block of TNF but not of IL-6 prevents bone loss in ovariectomized mice . J Bone Miner Res . 1997;12:935–941
- . Selective estrogen receptor modulators: clinical spectrum . Endocr Rev . 1999;20:418–434
- . Effect of estrogen and 1α,25(OH)2-vitamin D3 on the activity and growth of human primary osteoblast-like cells in vitro . Fertil Steril . 2002;77:1038–1043
- . CSF-1–a mononuclear phagocyte lineage-specific hemopoietic growth factor . J Cell Biochem . 1983;21:151–159
- . Identification and characterization of the new osteoclast progenitor with macrophage phenotypes being able to differentiate into mature osteoclasts . J Bone Miner Res . 2000;15:1477–1488
- . Effects of oestrogen deficiency on osteoclastogenesis in the rat periodontium . Arch Oral Biol . 2002;47:67–73
- . Estradiol and raloxifene decrease the formation of multinucleate cells in human bone marrow cultures . Eur Cytokine Netw . 2002;13:39–45
- . Estrogens suppress RANK ligand-induced osteoclast differentiation via a stromal cell independent mechanism involving c-Jun repression . Proc Natl Acad Sci U S A . 2000;14:7829–7834
- . Estrogen decreases osteoclast formation by down-regulating receptor activator of NF-κB ligand (RANKL)-induced JNK activation . J Biol Chem . 2001;276:8836–8840
- . Inhibition of bone resorption by 17β-estradiol in human bone marrow cultures . J Cell Physiol . 1998;175:99–108
PII: S1028-4559(09)60323-5
doi:10.1016/S1028-4559(09)60323-5
© 2009 Taiwan Association of Obstetrics and Gynecology. Published by Elsevier Inc. All rights reserved.
Volume 48, Issue 4 , Pages 350-355, December 2009
