Effects of ART on the levels of key molecules involved in TLR4-NF-κB signaling pathway in ulcerative colitis rats. (A) Western blot analysis of the effects of ART on the levels of key molecules involved in the TLR4-NF-κB signaling pathway. DSS-treatment increased the protein expression levels of TLR4, p-NF-κB, p-p38, Bax and caspase-9, and downregulated Bcl-2, whereas ART reversed these levels. (B) Reverse transcription-quantitative polymerase chain reaction analysis yielded similar results to the protein expression observations of western blot analysis. **P<0.01 and ***P<0.001, vs. CG; ##P<0.01 and ###P<0.001, vs. DG. ART, artesunate; TLR4, toll-like receptor 4; NF-κB, nuclear factor-κB; Bcl-2, B-cell lymphoma 2; Bax, Bcl-2-associated X protein; DSS, dextran sulfate sodium; CG, control group; DG, DSS-treated model group; LG, low-dose ART group; MG, middle-dose ART group; HG, high-dose ART group; PG, positive control group.