Table 2.

Activities of Bisphosphonates on Osteoclast Function at the Tissue, Cellular, and Molecular Levels

Tissue Level	Cellular Level	Molecular Level
↓ bone turnover due to ↓ bone resorption	↓ osteoclast recruitment	Inhibit mevalonate pathway (can result in perturbated cell activity and induction of apoptosis)
↓ number of new bone multicellular units	↑ osteoclast apoptosis	↓ post-translational prenylation of GTP-binding proteins
Net positive whole body bone balance	↓ osteoclast adhesion
	↓ depth of resorption site
	↓ release of cytokines by macrophages
	↑ osteoblast differentiation and number

GTP = guanosine triphosphate.

Adapted from reference ³⁰.