RRC ID 12049
Author Kanno S, Hirano S, Kayama F.
Title Effects of the phytoestrogen coumestrol on RANK-ligand-induced differentiation of osteoclasts.
Journal Toxicology
Abstract Phytoestrogens, which have structural similarity to 17beta-estradiol, have been reported to act as agonists/antagonists of estrogen in animals and humans. Estrogen is known to have an important role in maintaining bone mass, because the concentration of serum estrogen decreases after menopause and the estrogen deficiency causes bone loss. In this study, we investigated the effects of coumestrol and other phytoestrogens on osteoclast differentiation using estrogen receptor alpha-transfected RAW264.7 (RAW264.7-ERalpha) cells. When the cells were cultured with the receptor activator of nuclear factor kappa B-ligand (RANKL), both formation of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells and TRAP activity were increased compared with control cells that were cultured in the absence of RANKL. Coumestrol decreased RANKL-induced formation of TRAP-positive multinucleated cells and TRAP activity dose-dependently. RANKL-stimulated RAW264.7-ERalpha cells formed resorption pits on calcium phosphate films and the pit formation was inhibited by coumestrol in a dose-dependent manner. RT-PCR analyses revealed that coumestrol (10 microM) decreased mRNA levels of calcitonin receptor (CTR) and matrix metalloproteinase-9 (MMP9) in RANKL-treated cells. In addition, pretreatment of coumestrol decreased RANKL-induced phosphorylation of extracellular signal-regulated kinases/p44/42 (ERK1/2). These results suggest that coumestrol has an inhibitory effect on the differentiation of osteoclasts, at least partially via ERK1/2 pathway.
Volume 203(1-3)
Pages 211-20
Published 2004-10-15
DOI 10.1016/j.tox.2004.06.015
PII S0300483X0400335X
PMID 15363596
MeSH Acid Phosphatase / metabolism Animals Biomarkers Blotting, Western Bone Resorption / pathology Carrier Proteins / pharmacology* Cathepsin K Cathepsins / metabolism Cell Differentiation / drug effects Cell Line Coumestrol / pharmacology* Estradiol / pharmacology Estrogen Receptor alpha / metabolism Estrogens, Non-Steroidal / pharmacology* Giant Cells / drug effects Isoenzymes / metabolism Macrophages / physiology Matrix Metalloproteinase 9 / metabolism Membrane Glycoproteins / pharmacology* Mice Mitogen-Activated Protein Kinases / metabolism Osteoclasts / drug effects* Osteoclasts / ultrastructure RANK Ligand Receptor Activator of Nuclear Factor-kappa B Reverse Transcriptase Polymerase Chain Reaction Tartrate-Resistant Acid Phosphatase Transfection
IF 3.547
Times Cited 24
DNA material pUC-ER6 Rat uterus ER cDNA (RDB01376)