Brominated noscapine analogs induce autophagy in human macrophages.

<p><b>A</b>: Representative electron micrographs of human macrophage cells THP-1 treated overnight with LPS alone (2 pM concentration) or LPS and reduced bromo-noscapine (50 µM). Drug induced autophagy was noted with increased vacuolation in the cytoplasm. <b>B</b>: Western blot of autophagy marker LC3 protein in cell pellets shown in panel A. <b>C</b>: Fluorescence microscopic analysis of THP-1 cells treated for 24 hrs with DMSO (control), Red-Br-nos, LPS, Red-Br-nos and LPS followed by staining with 1 µg/ml acridine. Note the formation (red fluorescence) of acridine orange–accumulating acidic vesicular organelles (AVOs) in Red-Br-nos treated cells. <b>D</b>: Mouse TNFα release from RAW264.7 cells treated with the autophagy inhibitor 3-MA (50 µM) prior to stimulation with LPS alone or with 50 µM of Red-Br-nos, Br-nos or Nos. TNFα was measured by ELISA. The data represent two independent experiments. <i>p</i> values were calculated with reference to no 3-MA inhibitor and were <0.001 for Nos, Br-nos and Red-Br-nos drug treatment and LPS stimulation.