Galangin suppresses RANKL-induced osteoclastogenesis via inhibiting MAPK and NF-κB signalling pathways

Xiucheng Li1, Jiawei Jiang1, Zhifan Yang1

  • 1Department of Orthopaedics, Shaoxing People's Hospital, Zhejiang University School of Medicine, Shaoxing, China.

Insights

Galangin, a natural compound, effectively inhibits osteoclast formation and bone resorption, offering a potential new treatment for osteoporosis by targeting key signaling pathways.

Area of Science:

  • Biochemistry
  • Pharmacology
  • Cell Biology

Background:

  • Osteoclasts are crucial in osteoporosis pathogenesis.
  • Inhibiting osteoclastogenesis is a therapeutic target for osteoporosis.
  • Galangin, a natural bioflavonoid, has anti-inflammatory and anti-oxidative properties, but its effect on osteoporosis is unknown.

Purpose of the Study:

  • To investigate the effects of galangin on osteoclastogenesis and bone resorption.
  • To elucidate the molecular mechanisms underlying galangin's action in osteoporosis.

Main Methods:

  • Bone marrow-derived macrophages (BMMs) were treated with galangin to assess osteoclastogenesis.
  • Osteoclast-specific gene expression (TRAP, CtsK, V-ATPase d2, DC-STAMP) was analyzed.
  • Pit formation assays and F-actin ring staining evaluated osteoclastic bone resorption.
  • MAPK signaling pathway (p38, ERK) and downstream factors (NFATc1, C-Jun, C-Fos) were assessed.
  • Lipopolysaccharide (LPS)-induced bone resorption in vivo was examined.

Main Results:

  • Galangin dose-dependently decreased osteoclastogenesis in BMMs.
  • Galangin down-regulated key osteoclast-specific genes.
  • Impaired osteoclastic bone resorption was observed in galangin-treated groups.
  • Galangin inhibited MAPK signaling pathway phosphorylation and downstream factors.
  • Galangin suppressed LPS-induced bone resorption by inhibiting osteoclastogenesis.

Conclusions:

  • Galangin effectively inhibits osteoclastogenesis and bone resorption.
  • Galangin's mechanism involves the inhibition of MAPK and NF-κB signaling pathways.
  • Galangin shows promise as a natural therapeutic compound for osteoporosis treatment.

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