Agmatine Ameliorates Acetic Acid-Induced Colitis in Rats: Involvement of Nitrergic System Publisher Pubmed



Rashidian A^{1, 2} ; Keshavarzbahaghighat H^{1, 2} ; Abdollahi A³ ; Chamanara M⁴ ; Faghirghanesefat H^{1, 2} ; Hoseiniahmadabadi M¹ ; Dehpour AR^{1, 2} Show Affiliations
Source: Immunopharmacology and Immunotoxicology Published:2019

Abstract

Aim: The aim of the present study is to investigate the anti-inflammatory effect of agmatine through the inhibition of iNOS enzyme in acetic acid-induced rat colitis. Methods: Acute colitis was induced by administration of 2 mL of diluted acetic acid (4%) solution rectally. Two hours after colitis induction, animals were treated with normal saline, dexamethasone (2 mg/kg), agmatine (2, 5, 10 mg/kg), L-NAME (30 mg/kg), Aminoguanidine (20 mg/kg), agmatine (2 mg/kg) with L-NAME (30 mg/kg) and agmatine (2 mg/kg) with aminoguanidine (20 mg/kg) intraperitoneally and continued for 3 consecutive days. Assessment of macroscopic and microscopic damage was performed. MPO activity was evaluated by biochemical method. Furthermore, the tissue level of TNF-α was determined by ELISA and the expression level of iNOS protein was detected by immunohistochemistry (IHC). Results: Dexamethasone (2 mg/kg) and agmatine (5, 10 mg/kg) and subeffective doses of agmatine (2 mg/kg) with aminoguanidine (20 mg/kg) improved macroscopic and microscopic damage compared to acetic acid group (p <.001). In addition, these drugs reduced the activity of MPO (p <.001) and the level of TNF-α (p <.001) in colon tissue compared to acetic acid group. Furthermore, they decreased acetic acid-induced expression of iNOS protein in colon tissue (p <.01, p <.001). Conclusion: It is suggested that the anti-inflammatory activity of agmatine on acetic acid-induced rat colitis may involve the inhibition of iNOS enzyme. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.