Effect of estrogen on the activity and growth of human osteoclasts in vitro

Taiwan J Obstet Gynecol. 2009 Dec;48(4):350-5. doi: 10.1016/S1028-4559(09)60323-5.


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 17beta-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.

MeSH terms

  • Acid Phosphatase / metabolism
  • Bone Marrow Cells / cytology
  • CD11b Antigen / metabolism
  • Cells, Cultured
  • Coculture Techniques
  • Estradiol / deficiency
  • Estradiol / pharmacology*
  • Fetal Blood / cytology
  • Humans
  • Integrin alphaVbeta3 / metabolism
  • Isoenzymes / metabolism
  • Lipopolysaccharide Receptors / metabolism
  • Macrophages / cytology
  • Macrophages / metabolism
  • Monocytes / cytology
  • Osteoblasts / cytology
  • Osteoblasts / metabolism
  • Osteoclasts / cytology*
  • Osteoclasts / drug effects*
  • Osteoporosis, Postmenopausal / metabolism*
  • Osteoporosis, Postmenopausal / pathology*
  • Tartrate-Resistant Acid Phosphatase
  • Vitronectin / metabolism


  • CD11b Antigen
  • ITGAM protein, human
  • Integrin alphaVbeta3
  • Isoenzymes
  • Lipopolysaccharide Receptors
  • Vitronectin
  • Estradiol
  • Acid Phosphatase
  • Tartrate-Resistant Acid Phosphatase