Bone Mass Regulation Mechanisms and Cellular Interactions

Bone mass is governed by a dynamic equilibrium between bone formation by osteoblasts and bone resorption by osteoclasts, orchestrated by osteocytes that sense mechanical load and coordinate remodelling. Signalling pathways such as RANKL–RANK, Wnt/β-catenin and parathyroid hormone (PTH) receptor cascades integrate hormonal and mechanical cues to adjust bone turnover. Cellular crosstalk occurs through direct cell–matrix adhesion structures, secreted factors (paracrine signals) and matrix-bound growth factors. Megakaryocytes, traditionally known for platelet production, also secrete factors that influence both osteoblast and osteoclast function, coupling angiogenesis with osteogenesis. Advances in conditional gene manipulation and single-cell profiling have revealed lineage-specific regulators—such as focal adhesion proteins and autophagy components—that fine-tune receptor signalling and cytoskeletal organisation. Understanding these mechanisms has global relevance for developing targeted therapies for osteoporosis, fracture healing and other metabolic bone disorders.

Research from Nature Portfolio

Recent studies have shown that deletion of the focal adhesion protein Kindlin-2 in osteocytes impairs skeletal responses to mechanical loading. Loss of Kindlin-2 disrupts focal adhesion formation, cytoskeletal organisation and the downregulation of sclerostin, leading to sustained bone loss in weight-bearing bones. In parallel, megakaryocyte-derived conditioned media has been shown to modulate bone cell activity in ovariectomised models by suppressing osteoclast resorption while promoting osteoblast proliferation. This dual action increases trabecular bone volume and highlights the importance of paracrine factors from haematopoietic cells in coordinating the balance between bone formation and resorption.

Bone Mass Regulation Mechanisms and Cellular Interactions publication trend

The graph below shows the total number of articles in bone mass regulation mechanisms and cellular interactions across all publications each year (not limited to Nature Index journals).

Technical terms

Osteoblast: A bone-forming cell responsible for synthesis and mineralisation of the extracellular matrix.

Osteoclast: A multinucleated cell that degrades bone tissue during resorption.

Osteocyte: A mature bone cell embedded in the matrix that senses mechanical load and regulates remodelling.

Mechanotransduction: The process by which cells convert mechanical stimuli into biochemical signals.

Paracrine signalling: Cell-to-cell communication via locally secreted factors that act on neighbouring cells.

Sclerostin: A glycoprotein produced by osteocytes that inhibits bone formation by antagonising Wnt signalling.

RANKL: A ligand produced by osteoblast lineage cells that stimulates osteoclast formation and activity.

Megakaryocyte: A large bone marrow cell lineage precursor of platelets that can modulate bone cell function by secreted factors.

References

1. Beclin 1 of megakaryocytic lineage cells is locally dispensable for platelet hemostasis but functions distally in bone homeostasis. Bone Research (2025).
2. Kindlin-2 regulates skeletal homeostasis by modulating PTH1R in mice. Signal Transduction and Targeted Therapy (2020).
3. Megakaryocytes promote bone formation through coupling osteogenesis with angiogenesis by secreting TGF-β1. Theranostics (2020).
4. Kindlin-2 mediates mechanotransduction in bone by regulating expression of Sclerostin in osteocytes. Communications Biology (2021).
5. Regulation of bone metabolism by megakaryocytes in a paracrine manner. Scientific Reports (2020).
6. S100 Calcium-Binding Protein P Secreted from Megakaryocytes Promotes Osteoclast Maturation. International Journal of Molecular Sciences (2021).
7. Inhibition of Osteoblast Differentiation by JAK2V617F Megakaryocytes Derived From Male Mice With Primary Myelofibrosis. Frontiers in Oncology (2022).