Inhibitory effects of cecropin-TY1 on LPS-stimulated pro-inflammatory cytokines production in mouse peritoneal macrophages. a–c Inhibitory effects of cecropin-TY1 on LPS-stimulated (a) TNF-α, (b) IL-1β and (c) IL-6 transcription. The transcription levels of pro-inflammatory cytokines in peritoneal macrophages after different treatment were normalized to GAPDH. The transcription levels of pro-inflammatory cytokine in macrophages induced by 100 ng/mL LPS were arbitrarily defined as 100 %. Data were presented as mean ± SEM. *P <0.05, **P < 0.01, values of peptide-treated groups are significantly different from that induced by 100 ng/mL LPS alone. d–f Inhibitory effects of cecropin-TY1 on LPS-stimulated (d) TNF-α, (e) IL-1β and (f) IL-6 production. Peritoneal macrophages were stimulated with or without LPS (100 ng/mL), then different concentrations of cecropin-TY1 (cec-TY1, 5, 10, 20 μg/mL) were added as indicated and incubated for 6 h to detect pro-inflammatory cytokine transcription and production. Data were presented as mean ± SEM. *P <0.05, **P < 0.01, values of peptide-treated groups are significantly different from that induced by 100 ng/mL LPS alone. g–i Effects of the derivatives of cecropin-TY1 on LPS-stimulated (g) TNF-α, (h) IL-1β and (i) IL-6 production. Peritoneal macrophages were stimulated with 100 ng/mL LPS, then peptides (5 μM) were added and incubated for 6 h to detect pro-inflammatory cytokine production. Data were presented as mean ± SEM. *P <0.05, **P < 0.01, values of derivative-treated groups are significantly different from that of cecropin-TY1-treated group