Induced osteoclastogenesis by fluoroquinolones in unstimulated and stimulated human osteoclast precursor cells

► The cellular and molecular effects of five fluoroquinolones (ofloxacin, norfloxacin, ciprofloxacin, levofloxacin and moxifloxacin) on human osteoclastognesis were addressed. ► Unstimulated or stimulated (treated with M-CSF and RANKL) human peripheral blood was used. ► All the tested fluoroquinolones have the ability to modulate osteoclastogenesis in a time- and dose-dependent way. ► The effects of fluoroquinolones were observed for a wide range of concentrations that fall within the human serum concentrations. ► Some differences were noted in the intracellular signaling pathways tested, namely NFkB, MEK and PGE2 production.