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Mapk7 enhances osteogenesis and suppresses adipogenesis by activating Lrp6/β-catenin signaling axis in mesenchymal stem cells

  • 0Research Center for Translational Medicine, The First Affiliated Hospital of Sun Yat-sen University, 510080 Guangzhou, China.
Communications Biology +

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February 25, 2025

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February 25, 2025

View abstract on PubMed

Summary

This summary is machine-generated.

Mitogen-activated protein kinase 7 (MAPK7) is crucial for bone health. Depleting MAPK7 in mesenchymal stem cells causes low bone mass and osteoporosis by disrupting differentiation pathways.

Area Of Science

  • Biochemistry
  • Cell Biology
  • Orthopedics

Background

  • Mesenchymal stem cells (MSCs) are vital for bone homeostasis.
  • The role of Mitogen-activated protein kinase 7 (MAPK7) in MSC differentiation is unclear.
  • MAPK signaling pathways influence cell fate decisions.

Purpose Of The Study

  • To investigate the specific function of MAPK7 in regulating osteogenic and adipogenic differentiation of MSCs.
  • To elucidate the molecular mechanisms by which MAPK7 controls MSC lineage commitment.
  • To assess the potential of MAPK7 as a therapeutic target for bone diseases.

Main Methods

  • Utilized a genetic mouse model (Prx1-Cre x Mapk7<sup>flox/flox</sup>) to deplete Mapk7 in MSCs.
  • Performed in vitro experiments involving gene knockout and overexpression of Mapk7 in MSCs.
  • Analyzed Wnt/β-catenin signaling pathway activation, including Lrp6 phosphorylation at Ser1490.

Main Results

  • Mapk7 depletion in mice led to severe low bone mass and increased bone marrow fat, indicative of osteoporosis.
  • Mapk7 promoted osteogenic differentiation and inhibited adipogenic differentiation of MSCs in vitro.
  • Mapk7 activates the Wnt/β-catenin pathway by phosphorylating Lrp6, thereby enhancing osteogenesis and suppressing adipogenesis.

Conclusions

  • MAPK7 plays a critical role in maintaining bone mass by regulating MSC differentiation.
  • MAPK7 promotes osteogenesis and inhibits adipogenesis through the Wnt/β-catenin signaling pathway.
  • Targeting MAPK7 may offer a novel therapeutic strategy for osteoporosis and other MSC differentiation imbalance-related bone disorders.

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