Fig. 9
Effects of piperine on LPS-induced M1-like polarization in RAW264.7 cells. RAW264.7 cells were pretreated with piperine at 20–80 μM for 12 h and then stimulated by LPS (1 μg/ml) for 24 h. a-c The mRNA levels of CD11c, IL-1β and TNF-α were analyzed by qPCR. d The IL-1β level in cell supernatant was measured by ELISA. e-f The protein levels of TLR-4, CD11c and IL-1β were tested by Western Blotting. Data are expressed as mean ± SD, n = 3. ####p < 0.0001 vs. Control group; **p < 0.01, ***p < 0.001, ****p < 0.0001 vs. LPS group. (The original, unprocessed gel images are included in the additional file 1)