Rotenone impairs osteoclastogenesis by inhibiting cell migration: insights from machine learning

Purpose: The migration and fusion of osteoclast precursors (OCPs) are critical steps in osteoclastogenesis and require substantial energy. Although Oxidative Phosphorylation (OXPHOS) is generally considered the major pathway supplying energy for these processes, it remains unclear how inhibiting OXPHOS affects the migration of OCPs.

Materials and methods: To investigate the metabolic regulation of osteoclast migration, we used a recognized OXPHOS inhibitor rotenone to suppress the key energy-producing pathway in OCPs. We combined this intervention with bioinformatics approaches and machine learning algorithms to screen and identify genes associated with osteoclast dysfunction in patients with osteoporosis. The migratory capacity of OCPs was precisely quantified using optical tweezers.

Results: We found that rotenone inhibited osteoclastogenesis and markedly impaired the migratory capacity of OCPs. Although the level of OXPHOS in OCPs decreased, intracellular ATP content paradoxically increased, suggesting that the impairment of migratory capacity is unlikely to be driven by an overall energy shortage. Through machine learning algorithms, we identified genes associated with abnormal osteoclast function in patients with osteoporosis and discovered their critical regulatory roles in processes such as cell migration, adhesion, and OXPHOS. Rotenone significantly suppressed the expression of these genes in OCPs, suggesting a direct mechanism for the impaired migration.

Conclusions: In summary, our study reveals a novel mechanism for rotenone-induced inhibition of osteoclastogenesis, which is achieved by impairing the migration of OCPs in a manner uncoupled from overall energy status.