Fig. 1.

Effects of zoledronic acid on the expression of M1/M2 macrophage markers in LPS-treated THP-1 cells. THP-1 cells were treated overnight with 100 ng/ml PMA, then washed and incubated for 24 h. a Cell viability was assessed using a WST-8 assay after treatment with Zol (1–1000 nM) for 48 h. b THP-1 cells were incubated with or without Zol for 24 h and then treated with 100 ng/ml LPS. Open bars represent LPS-treated THP-1 cells; filled bars represent Zol and LPS-treated THP-1 cells. Zol upregulated the expression of IL-1β mRNA and downregulated the expression of IL-1ra mRNA in LPS-treated THP-1 cells (* P < 0.05, ** P < 0.01 vs. cells treated with LPS alone). c ATP was applied to LPS-treated cells for 30 min before collecting samples. The secretion of IL-1β at 18 h and IL-1ra at 36 h was detected by ELISA. Zol upregulated the secretion of IL-1β and downregulated the secretion of IL-1ra in LPS-treated THP-1 cells (** P < 0.01 vs. cells treated with LPS alone)