# (-)-Fenchone Ameliorates TNBS-Induced Colitis
## 2 Results
### Effect of (-)-Fenchone in Intestinal Acute Inflammation in a TNBS-Induced Colitis Model
#### 2.1.1 Histological Analysis  
Histological sections of the colon belonging to the non-colitic, prednisolone, and (-)-fenchone (150 mg/kg) groups were stained with hematoxylin and eosin fenchone (Figure 2A,C,D); the integrity of the mucosa (M) and goblet cells is observed. In the colitic group (5% tweeen 80) (Figure 2B), intense mucosal destruction is observed, with ulcer formation, which is characterized by organ surface necrosis and intense acute inflammatory reaction (*) and increased leukocyte infiltrate. In sections stained with Masson's trichrome, it was found that (-)-fenchone (150 mg/kg) (Figure 2H) reduced extracellular matrix deposition (_p_ < 0.001) 9.00 (5-19) compared to the colitic group (5% tweeen 80) who presented scar tissue (\(\infty\)) in the area of the mucosal ulcer (_p_ < 0.001) 30.50 (20-35) (Figure 2F) (Figure 1). 1.2 Effect of (-)-Fenchone in the Modulation of Antioxidant and Anti-Inflammatory Properties in Acute Colitis GSH  
In determining the antioxidant activity of (-)-fenchone, it was possible to verify that the colitic group (5% tweeen 80) showed a reduction in GSH levels to 36.7 \(\pm\) 5.9 nmol of GSH/mg protein compared to the normal group (68.5 \(\pm\) 4.6 nmol GSH/mg protein). Figure 2: Microscopic effects of the colon of rats submitted to acute TNBS-induced ulcerative colitis model and treated or not with (-)-fenchone. Representative photomicrographs of the animals’ colons from the experimental groups: HE staining of non-colitic (**A**), colitic (5% tweeen 80) (**B**), prednisolone 2 mg/kg (**C**), and (-)-fenchone 150 mg/kg (**D**). Masson trichrome—non-colitic (**E**), colitic (5% tweeen 80) (**F**), prednisolone 2 mg/kg (**G**), and (-)-fenchone 150 mg/kg (**H**). Colonic mucosa (M), acute inflammatory reaction (*), scarring tissue (\(\infty\)). Results are expressed as the median (minimum-maximum) of the parameters analyzed (n = 5, 3 sessions per animal). Kruskal–Wallis test and Dunn’s posterior test were performed using the software Graph Pad Prism 6. *** \(p\) < 0.001 compared to the non-colitic group (5% tweeen 80). However, administration of (-)-fenchone (150 mg/kg) to 55.9 \(\pm\) 6.5 nmol GSH/mg protein) restored baseline GSH levels (Figure 3A). SOD  
Animals in the colitic group (5% tween 80) demonstrated a significant reduction in the activity of the SOD enzyme to 0.24 \(\pm\) 0.09 U of SOD/mg of the protein compared to the normal group (2.32 \(\pm\) 0.37 U SOD/mg of protein). However, SOD activity was significantly increased (\(p\) < 0.001) with the administration of (-)-fenchone (150 mg/kg) to 2.28 \(\pm\) 0.29 of SOD/mg of the protein, respectively, when compared to the colitic group (5% tween 80) (Figure 3B). MDA  
The colitic group (5% tween 80) showed an increase in MDA levels to 173.2 \(\pm\) 26.8 nmol MDA/g tissue compared to the normal group (109.5 \(\pm\) 12.07 nmol MDA/g tissue). However, the administration of prednisolone (2 mg/kg) (109.5 \(\pm\) 12.43 nmol of MDA/g tissue) or (-)-fenchone (150 mg/kg) (115.2 \(\pm\) 15.84 nmol MDA/g of tissue) respectively, when compared to the colitic group (Figure 3C). MPO  
The results showed that in the colitic group (5% tween 80), there was an increase in MPO levels to 62.06 \(\pm\) 8.41 units of MPO/g of tissue when compared to the normal group (14.39 \(\pm\) 3.53 units MPO/g tissue). However, the groups treated with prednisolone (2 mg/kg) or (-)-fenchone (150 mg/kg) significantly reduced MPO levels to 35.28 \(\pm\) 5.54 and 30.44 \(\pm\) 6.90 units of MPO/g of tissue, respectively, in relation to the colitic group (Figure 3D). Figure 3: Effect of oral administration of (-)-fenchone and prednisolone in GSH (**A**), SOD (**B**), MDA (**C**), and MPO (**D**) levels from acute TNBS-induced ulcerative colitis model in rats. Results are expressed as mean \(\pm\) SE of the parameters analyzed (n = 5–8). The one-way ANOVA followed by [PERSON]’s and Tukey’s test. **\(p\)** < 0.01 or **\(p\)** < 0.001 vs. non-colitic group.