Osteoclast activity and subtypes as a function of physiology and pathology--implications for future treatments of osteoporosis

Endocr Rev. 2011 Feb;32(1):31-63. doi: 10.1210/er.2010-0006. Epub 2010 Sep 17.


Osteoclasts have traditionally been associated exclusively with catabolic functions that are a prerequisite for bone resorption. However, emerging data suggest that osteoclasts also carry out functions that are important for optimal bone formation and bone quality. Moreover, recent findings indicate that osteoclasts have different subtypes depending on their location, genotype, and possibly in response to drug intervention. The aim of the current review is to describe the subtypes of osteoclasts in four different settings: 1) physiological, in relation to turnover of different bone types; 2) pathological, as exemplified by monogenomic disorders; 3) pathological, as identified by different disorders; and 4) in drug-induced situations. The profiles of these subtypes strongly suggest that these osteoclasts belong to a heterogeneous cell population, namely, a diverse macrophage-associated cell type with bone catabolic and anabolic functions that are dependent on both local and systemic parameters. Further insight into these osteoclast subtypes may be important for understanding cell-cell communication in the bone microenvironment, treatment effects, and ultimately bone quality.

Publication types

  • Review

MeSH terms

  • Animals
  • Antirheumatic Agents / therapeutic use
  • Arthritis, Rheumatoid / drug therapy
  • Arthritis, Rheumatoid / metabolism
  • Bone Resorption / drug therapy
  • Bone Resorption / metabolism
  • Humans
  • Mice
  • Osteitis Deformans / metabolism
  • Osteoclasts / metabolism*
  • Osteoclasts / pathology
  • Osteoclasts / physiology
  • Osteoporosis / drug therapy
  • Osteoporosis / metabolism*
  • RANK Ligand / metabolism
  • Rats


  • Antirheumatic Agents
  • RANK Ligand