Fig. 2

LPS suppresses the formation of autophagosomes without influencing the function of lysosomes. a N9 microglial cells were exposed to 1 μg/mL LPS for 6 h, 12 h, and 24 h. The expressions of SQSTM1, an autophagy substrate, and LAMP2, a lysosome membrane protein, were detected by western blotting and quantified (b, c). d Levels of Cathepsin E (CTSE) were determined by western blotting in microglial cells treated with LPS for 6 h, 12 h, and 24 h, and quantified (e). f N9 microglial cells were treated with 1 μg/mL LPS for 6 h, 12 h, and 24 h, or with 100 nM bafilomycin A1 for 6 h. The fluorescence intensity of LysoSensor was recorded with a 443-nm excitation filter and a 505-nm emission filter. g N9 microglial cells were treated with LPS in the presence or absence of 10 μΜ chloroquine (CQ) for 24 h. The expression of autophagy-related proteins was measured by western blotting and quantified (h, i). Data are presented as mean ± SEM. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001 vs control; ^#p < 0.05, ^##p < 0.01 vs CQ