Evaluation of the Therapeutic Effect of Achillea wilhelmsii C. Koch Aqueous Extract in Acetic-acid-induced Ulcerative Colitis in Rat

Context: Ulcerative colitis (UC) is a chronic, idiopathic, and recurrent disease with unknown etiology. Achillea wilhelmsii has been introduced as a herbal remedy for gastrointestinal ulcers and UC in traditional Persian medicine. 
Aims: We examined the effectiveness of A. wilhelmsii aqueous extract against acetic-acid-induced UC in rats. 
Settings and Design: Fifty-six male Wister albino rats weighing 180–200 g were randomly divided into eight groups and after induction of UC were treated with five doses of aqueous extract of A. wilhelmsii. 
Materials and Methods: After induction of UC by acetic acid, the aerial parts of A. wilhelmsii (6.25, 12.5, 25, 50, and 100 mg/kg) were administered orally. On 11th day, the animals were euthanized by overdose of ether inhalation and the intestinal tissue was rapidly dissected for macroscopic, histological, and microscopic scores. 
Statistical Analysis Used: Data were analyzed by stats Directver.2.7.9 (SAS, Cary, North Carolina). One-way analysis of variance (ANOVA) followed by Newman–Keul’s post hoc test for multiple comparisons. A value of P < 0.05 was considered as significant level. Results were expressed as mean ± standard error of the mean (SEM). 
Results: All doses of A. wilhelmsii extract significantly reduced macroscopic and microscopic scores of colitis without significant changes in bodyweight of animals. 
Conclusions: Treatment of the rats with A. wilhelmsii extract improved UC via its anti-inflammatory, antioxidant, and antimicrobial activities. According to the results of this study, A. wilhelmsii has a therapeutic effect against acetic-acid-induced UC in the animal model.