Overexpression of HMGB1 A-box reduced lipopolysaccharide-induced intestinal inflammation via HMGB1/TLR4 signaling in vitro

Figure 6 Expression of the HMGB1 protein and TLR4 signaling pathways in THP-1 cells co-cultured with SW480 cells. After pretreatment with EP (5 mmol/L, 1 h), the SW480 cells were treated with 1 μg/mL LPS and co-cultured with THP-1 cells for 24 h. The HMGB1, TLR4, MYD88, pNF-κB p65 mRNA and protein levels were determined by real-time PCR (A, C, E), densitometric quantification and representative western blots, with β-actin as the loading control (B, D, F, G, H). Compared with the LPS-untreated group, LPS increased HMGB1, TLR4, MYD88, pNF-κB p65 mRNA and protein levels in the THP-1 cells, but EP downregulated these levels. Similarly, HMGB1 A-box also downregulated HMGB1, TLR4, MYD88, pNF-κB p65 mRNA and protein levels compared with the mock-transfected group. The data are expressed as the mean ± SD and are derived from three independent experiments, which were each performed in duplicate. The means with letters above them are significantly different (^aP < 0.05, ^bP < 0.01 vs control).