Figure 4.
The protective effects of osthole against TNBS-induced colitis were mainly mediated by the cAMP/PKA-independent pathway. (A) Serum cAMP levels were determined 2 d after the initial rectal TNBS administration. (B) H89 was intraperitoneally administered at 10 mg/kg 1 h prior to TNBS. The changes in the body weights of mice were determined. (C) H89 was intraperitoneally administered at 10 mg/kg 1 h prior to TNBS treatments. The animals were sacrificed on d 2 post-TNBS treatments, and the colon lengths were determined. (D) Mouse peritoneal macrophages were isolated and incubated with 50 μmol/L osthole for 24 h. Cells were then treated with 10 μmol/L H89 or 1 μmol/L KT5720 for 2 h before being exposed to 10 ng/mL LPS. After another 4 h, the cellular mRNA samples were extracted and quantified by real-time RT-PCR. Data are expressed as the mean±SEM (numerical data are shown in the Supplementary file), n=5–9 mice or n=3 wells per group. *P<0.05 compared to control. #P<0.05 compared to TNBS or LPS. §P<0.05 compared to TNBS plus osthole or LPS plus osthole.