S100A8 induces pro-inflammatory cytokines and inflammation in BV-2 cells. BV-2 cells were stimulated with S100A8 (10 μg/mL) for 24 h. (A) The supernatant was collected and TNF-α and interleukin-6 (IL-6) analyzed by ELISA. (B) The protein and mRNA were extracted, and the expression levels of IL-1β were assessed by ELISA and RT-qPCR. (C–E) The protein was extracted, separated on 10% SDS-acrylamide gels (15 μg/lane) and transferred to nitrocellulose membrane. The protein expression level was detected by western blotting with anti-ERK1/2, anti-phospho-ERK1/2 (p-ERK1/2), anti-JNK and anti-p-JNK. (F) Cells were pre-treated with ERK inhibitor (PD98059, 20 μM), JNK inhibitor (SP600125, 10 μM) or the equivalent volume of DMSO for 1 h, then stimulated for 24 h with LPS or S100A8 for ELISA of TNF-α, IL-6. Data from three independent experiments are presented as the means ± S.D. Values of * p < 0.05, *** p < 0.001 versus control; ### p < 0.001 versus S100A8-treated sample were considered as statistically significant.