Evaluation of the Protective Effect of the Secondary Root's Extract and Partitions of Devil's Claw (Harpagophytum procombens) on Ulcerative Colitis Caused by Acetic Acid in Rats.

BACKGROUND: Ulcerative colitis is an autoimmune disease with an unfamiliar etiology, which caused by environmental, microbial, and genetic factors. Harpagophytum procumbens (H. procumbens, Devil's Claw), could be effective in the treatment of colitis due to its strong anti-inflammatory, antioxidant and restorative effects. Therefore, this research aimed to explore this property. METHODS: The hydroalcoholic extract of H. procumbens was prepared and partitioned into aqueous and ethyl acetate parts. Total phenols of extract and partitions were determined and three increasing doses of them (50, 100, and 200 mg/kg), dexamethasone (1 mg/kg), mesalazine (100 mg/kg) and normal saline (5 mL/kg) were examined in male Wistar rats as test, reference and control groups respectively. Colitis induction was conducted via rectal instillation of acetic acid and the treatments continued for five consecutive days. Finally, the colon tissues were evaluated for colitis biomarkers. RESULTS: Total phenols were equivalent to 5.19 ± 0.09, 2.12 ± 0.03 and 7.71 ± 0.01 gallic acid equivalent (mg)/g of dry extract, aqueous and ethyl acetate partitions, respectively. Greater doses of hydroalcoholic extract and aqueous (200 mg/kg) and ethyl acetate partition (50, 100 and 200 mg/kg) improved the ulcerative colitis in terms of colon weight, ulcer index and total colitis index in significant manner. Similar results obtained after myeloperoxidase (MPO) measurements however, for malondialdehyde (MDA) value, most doses of the extract and partitions were effective. CONCLUSIONS: H. procumbens hydroalcoholic extract and its partitions ameliorated experimental colitis probably in a dose-related manner. It seems antioxidant, anti-inflammatory and anti-ulcerative effects especially due to non-polar ingredients, are responsible.