Objective      To determine the effect of oxygen and paclitaxel loaded liposome microbubbles mediated by ultrasound on the expression of HIF-1α in hypoxia macrophages.  Methods      Hypoxia model of macrophages RAW264.7 was induced by CoCl2. Hypoxic RAW264.7 cells were randomly divided into control

paclitaxel group (6×10-6 mol/L)

ultrasound group (0.5 W/cm2

30 s)

oxygen loaded liposome microbubbles (25 μL)

oxygen and paclitaxel loaded liposome microbubbles group (25 μL)

oxygen and paclitaxel loaded liposome microbubbles plus ultrasound group (25 μL

0.5 W/cm2

30 s). Cell viability was measured by MTT assay. The expression of HIF-1α at mRNA and protein levels was measured in the hypoxic macrophages by RT-PCR or Western blotting. ELISA was used to detect the levels of TNF-α and IL-6 secreted by the macrophages after treatments.  Results      Treatment of 100 μmol/L CoCl2 for 12 h inhibited the cell viability in the RAW264.7 cells by less than 8% and successfully induced the cells into a hypoxic state. Oxygen and paclitaxel loaded liposome microbubbles mediated by ultrasound could significantly suppress the expression of HIF-1α at mRNA and protein levels

and the secretions of TNF-α and IL-6 (P0.05).  Conclusion     Oxygen and paclitaxel loaded liposome microbubbles mediated by ultrasound effectively inhibits the expression of HIF-1α in hypoxic macrophages

and attenuates the hypoxic state.