Anti-osteoclastogenic activity of praeruptorin A via inhibition of p38/Akt-c-Fos-NFATc1 signaling and PLCγ-independent Ca2+ oscillation

PLoS One. 2014 Feb 21;9(2):e88974. doi: 10.1371/journal.pone.0088974. eCollection 2014.

Abstract

Background: A decrease of bone mass is a major risk factor for fracture. Several natural products have traditionally been used as herbal medicines to prevent and/or treat bone disorders including osteoporosis. Praeruptorin A is isolated from the dry root extract of Peucedanum praeruptorum Dunn and has several biological activities, but its anti-osteoporotic activity has not been studied yet.

Materials and methods: The effect of praeruptorin A on the differentiation of bone marrow-derived macrophages into osteoclasts was examined by phenotype assay and confirmed by real-time PCR and immunoblotting. The involvement of NFATc1 in the anti-osteoclastogenic action of praeruptorin A was evaluated by its lentiviral ectopic expression. Intracellular Ca(2+) levels were also measured.

Results: Praeruptorin A inhibited the RANKL-stimulated osteoclast differentiation accompanied by inhibition of p38 and Akt signaling, which could be the reason for praeruptorin A-downregulated expression levels of c-Fos and NFATc1, transcription factors that regulate osteoclast-specific genes, as well as osteoclast fusion-related molecules. The anti-osteoclastogenic effect of praeruptorin A was rescued by overexpression of NFATc1. Praeruptorin A strongly prevented the RANKL-induced Ca(2+) oscillation without any changes in the phosphorylation of PLCγ.

Conclusion: Praeruptorin A could exhibit its anti-osteoclastogenic activity by inhibiting p38/Akt-c-Fos-NFATc1 signaling and PLCγ-independent Ca(2+) oscillation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acid Phosphatase
  • Calcium / metabolism
  • Cell Differentiation / drug effects*
  • Coumarins / chemistry
  • Coumarins / pharmacology*
  • DNA Primers / genetics
  • Humans
  • Immunoblotting
  • Isoenzymes
  • MAP Kinase Signaling System / drug effects*
  • Macrophages / cytology*
  • Macrophages / drug effects
  • Molecular Structure
  • NFATC Transcription Factors / metabolism
  • Oncogene Protein v-akt / metabolism
  • Osteoclasts / cytology*
  • Osteoclasts / drug effects
  • Osteoporosis / prevention & control*
  • Phospholipase C gamma / metabolism
  • Proto-Oncogene Proteins c-fos / metabolism
  • Real-Time Polymerase Chain Reaction
  • Tartrate-Resistant Acid Phosphatase

Substances

  • Coumarins
  • DNA Primers
  • Isoenzymes
  • NFATC Transcription Factors
  • NFATC1 protein, human
  • Proto-Oncogene Proteins c-fos
  • praeruptorin A
  • Oncogene Protein v-akt
  • Acid Phosphatase
  • Tartrate-Resistant Acid Phosphatase
  • Phospholipase C gamma
  • Calcium

Grants and funding

This work was supported by the Korea Research Institute of Chemical Technology project’s grant (SI-1304) and the Inter-ER Cooperation Projects (R0002019) of Korea Institute for Advancement of Technology, which were funded by the Korea Ministry of Knowledge Economy. MSK was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF-2012R1A1A1038381), funded by the Ministry of Education, Science and Technology (MEST). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.