Immunoregulatory cytokines in mouse placental extracts inhibit in vitro osteoclast differentiation of murine macrophages.

Abstract

INTRODUCTION:

Previous studies showed that placental extracts (PE) alleviates arthritic symptoms in animal models of arthritis.

METHODS:

To evaluate whether murine PEs obtained at embryonic days 7.5 (PE7) and 17.5 (PE18) regulate RANKL-induced osteoclast differentiation, RAW 264.7 cells were cultured with RANKL and MCSF in presence or not of PEs. Tartrate-resistant acid phosphatase (TRAP) was stained and multinucleated TRAP positive cells were visualized under a light microscope. Cathepsin K and metalloprotease expression was assessed by RT-PCR and gelatin zymography respectively. NFATc1 expression was determined by immunoblot. To analyze NFAT-dependent transcription, macrophages were transfected with a luciferase reporter plasmid. Cytokines were determined in PEs by ELISA and immunoblot. Transforming growth factor (TGF)- beta and Interleukin (IL)-10 receptor were inhibited in cell cultures with specific antibodies.

RESULTS:

PE7 and PE18 inhibited RANKL-induced multinucleated TRAP positive cells, Cathepsin K expression and metalloprotease activity, as well as NFATc1 expression and activity, thereby inhibiting osteoclast differentiation of RAW cells. Inflammatory/Regulatory cytokine ratio was higher in PE7 than in PE18. Blocking TGF-beta abolished the effect of both, PE7 and PE18, on multinucleated TRAP positive cells and metalloprotease expression, whereas blocking IL-10 receptor reverted the effect of PE18 but not of PE7.

DISCUSSION:

Inhibition of osteoclast differentiation by PEs was not unexpected, since cytokines detected in extracts were previously found to regulate osteoclast differentiation.

CONCLUSIONS:

PEs inhibited osteoclast differentiation of macrophages in vitro. Downregulation of NFATc1 might be involved in this effect. Regulatory/Th2 cytokines play a role in the effect of PEs on osteoclast differentiation.

• Authors: A Canellada, A Custidiano, F Abraham, E Rey, T Gentile
• Journal: Placenta (Placenta) Vol. 34 Issue 3 Pg. 231-9 (Mar 2013) ISSN: 1532-3102 [Electronic] Netherlands
• PMID: 23347887 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier Ltd. All rights reserved.

Chemical References

• Cytokines
• Isoenzymes
• NFATC Transcription Factors
• Nfatc1 protein, mouse
• RANK Ligand
• Tissue Extracts
• Tnfsf11 protein, mouse
• Transforming Growth Factor beta
• Acid Phosphatase
• Acp5 protein, mouse
• Tartrate-Resistant Acid Phosphatase
• Metalloproteases
• Cathepsin K

Topics

• Acid Phosphatase (metabolism)
• Animals
• Cathepsin K (metabolism)
• Cell Differentiation (drug effects)
• Cells, Cultured
• Cytokines (analysis, pharmacology)
• Embryo, Mammalian
• Female
• Isoenzymes (metabolism)
• Macrophages (cytology, drug effects)
• Metalloproteases (metabolism)
• Mice
• Mice, Inbred BALB C
• NFATC Transcription Factors (metabolism)
• Osteoclasts (cytology, drug effects, metabolism)
• Placenta (chemistry, metabolism)
• Pregnancy
• RANK Ligand (pharmacology)
• Tartrate-Resistant Acid Phosphatase
• Tissue Extracts (analysis, pharmacology)
• Transforming Growth Factor beta (antagonists & inhibitors)