ABSTRACT
The present study aimed to explore the effect of nuclear factor erythroid 2 related factor 2(Nrf2)/heme oxygenase-1(HO-1) signaling pathway in intestinal protection by Sishen Pills against ulcerative colitis(UC). After the UC model was induced by 3% dextran sodium sulfate(DSS), experimental animals were randomly divided into control group, model group, salazosulfapyridine(SASP) group, and low-and high-dose Sishen Pills groups. Drug intervention(ig) was performed for seven consecutive days during modeling. On the 7 th day, the mice were euthanized. The body weight and colon length were recorded, and the histopathological changes of the colon were observed by HE staining. Serum interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), total antioxidant capacity(T-AOC), malondialdehyde(MDA), and reactive oxygen species(ROS) were detected by ELISA. The protein and mRNA expression of Nrf2, HO-1, and NADPH quinine oxidoreductase-1(NQO-1) was determined by Western blot and reverse transcription-polymerase chain reaction(RT-PCR). Compared with the normal group, the model group exhibited reduced body weight, colon length, and T-AOC, increased IL-6, TNF-α, MDA, and ROS, and diminished protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. Compared with the model group, the SASP group and high-dose Sishen Pills group showed elevated body weight, colon length, and T-AOC, lowered IL-6, TNF-α, MDA, and ROS levels, and increased protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. As assessed by HE staining, Sishen Pills could improve the pathological changes of the colon. The findings suggested that Sishen Pills could protect the colon against UC induced by 3% DSS. The specific mechanism of action may be related to the anti-inflammatory and anti-oxidative stress effects by the activation of the Nrf2/HO-1 signaling pathway.
Subject(s)
Animals , Mice , Colitis, Ulcerative/genetics , Dextran Sulfate , Heme Oxygenase-1/metabolism , NF-E2-Related Factor 2/metabolism , Signal TransductionABSTRACT
<p><b>BACKGROUND</b>Our previous papers indicate that flurbiprofen axetil (FA), a cyclooxygenase inhibitor, is a promising therapeutic strategy for cerebral ischemia in rats. This study aimed to investigate whether FA could promote a neuroprotective effect by activation of peroxisome proliferator-activated receptor-γ (PPAR-γ) after focal cerebral ischemia in rats.</p><p><b>METHODS</b>Totally 48 male Sprague-Dawley (SD) rats were randomly assigned into six groups (n = 8 in each group): animals in group ischemia/reperfusion (I/R) only received 120-minute transient middle cerebral artery occlusion (tMCAO); animals in group I/R + FA were administered FA (10 mg/kg) by caudal vein just after 120-minute tMCAO; animals in group I/R + FA + GW9662 were administered GW9662 (a PPAR-γ inhibitor, 1 mg/kg) intraperitoneally 30 minutes before cerebral ischemia onset and FA (10 mg/kg) by caudal vein just after 120-minute tMCAO; animals in group I/R + GW9662 were administered GW9662 (1 mg/kg) intraperitoneally 30 minutes before cerebral ischemia onset; animals in group I/R + DMSO were administered 3% DMSO (vehicle of GW9662, 1 ml/kg) intraperitoneally 30 minutes before cerebral ischemia onset; animals in sham group experienced the identical surgery apart from the insertion of the nylon filament. The neurologic deficit score (NDS) were performed at 72 hours after reperfusion, and then mean brain infarct volume percentage (MBIVP) was determined with 2,3,5-triphenyltetrazolium chloride (TTC) 10 g/L staining.</p><p><b>RESULTS</b>NDS was significantly increased in group I/R + FA (12.0 (10.0 - 15.0)), group I/R + FA + GW9662 (10.0 (8.0 - 12.0)), and in group I/R + FA + DMSO (12.0 (9.0 - 14.0)) at 72 hours after reperfusion compared with those in group I/R (7.5 (6.0 - 10.0)). NDS was conspicuously different between group I/R + FA (12.0 (10.0 - 15.0)) and group I/R + FA + GW9662 (10.0 (8.0 - 12.0)). MBIVP in group I/R ((45.82 - 8.83)%) was significantly greater than that in group I/R + FA ((23.52 - 9.90)%), group I/R + FA + GW9662 ((33.17 - 7.15)%); MBIVP in group I/R + FA ((23.52 - 9.90)%) was significantly smaller than that in group I/R + FA + GW9662 ((33.17 - 7.15)%).</p><p><b>CONCLUSIONS</b>FA confers the neuroprotective effect on tMCAO in rats and the selective PPAR-γ antagonist GW9662 attenuates the effect of FA. FA could promote a neuroprotective effect by, or in part, activation of PPAR-γ after focal cerebral ischemia in rats.</p>