Effects of N-acetylcysteine Treatment on Oxidative Stress in Acetic Acid-induced Experimental Colitis in Rats

Abstract

We assessed the possible protective effects of N-acetylcysteine (NAC) against toxic damage in the rat colon. Two doses of NAC (20 mg/kg and 100 mg/kg) given for 2 days and 7 days after acetic acid administration (to induce colitis) were tested. NAC was dissolved in saline and administered locally (intracolonic), systemically (intraperitoneal) or in a combination (intracolonic and intraperitoneal). Several parameters, including macroscopic and histopathological scores and myeloperoxidase, glutathione and nitric oxide concentrations were measured using standard assay procedures. Treatment with 100 mg/kg NAC for 7 days significantly decreased tissue myeloperoxidase, glutathione and nitric oxide concentrations. The 20 mg/kg dose had no protective effects. The data indicate that NAC substantially reduced the degree of colonic injury, probably by regulating free radical production and inhibiting inflammation. It may, therefore, have a role in the treatment of inflammatory bowel disease.

Evaluation of topical n-acetylcysteine in diversion colitis

“…When considering that the use of substances with antioxidant activity can neutralize the harmful effects of OFRs, it becomes an interesting strategy for the treatment of diseases related to oxidative stress. Studies conducted in experimental models of chemically induced colitis confirmed the beneficial effects of antioxidants, improving the inflammatory process of colonic mucosa [27][28][29][30][31] . Several drugs have been tested with effective results in experimental conditions, including 5-ASA, glucocorticoids, L-carnitine, L-glutamine, melatonin and antioxidants found in the aqueous extract of Ilex paraguariensis and Curcuma longa [33][34][35][36][37][38][39] .…”

“…It is filterable and easily crosses the cellular membranes, with easy access to different intracellular compartments 29 . NAC has been used as an antioxidant both in vivo and in vitro, in different situations 29,30 and it has been used in clinical practice to treat several diseases, including pulmonary disorders caused by excess oxygen, against the paracetamol toxic effects, infection of human immunodeficiency virus, and the treatment of disorders caused by ischemia in liver, lungs and skin flaps 37,40,41 . The possibility of different pharmacological applications is regulated by the chemical properties of the group of thiol-cysteine molecules to eliminate OFRs 30 .…”

“…Studies that analyzed forms of chemically induced colitis showed that NAC improves the inflammatory process by removing OFRs created during the cellular energy metabolism 28,30 . The application of enemas with NAC was able to reduce inflammation in colitis induced by dextran sulfate (DSS) and acetic acid after removing OFRs and increasing the antioxidant activity of colonic mucosa [28][29][30][31] . However, despite the therapeutic effectiveness of NAC in chemically induced colitis, its effects have never been tested in forms of DC.…”

“…Histological photographs were taken using a digital video capture system (DSFi-50; Nikon Inc., Osaka, Japan) previously coupled to the microscope. The diagnosis of colitis and the tissue inflammatory grading score were determined according to the criteria previously described by Akgun et al 29 with modifications (Table 1). Statistical analysis Data obtained were described according to the median values.…”

“…N-acetylcysteine (NAC) is a substance with recognized antioxidant activity both in vitro and in vivo [28][29][30] , which has been used in the treatment of different inflammatory diseases. Studies that analyzed forms of chemically induced colitis showed that NAC improves the inflammatory process by removing OFRs created during the cellular energy metabolism 28,30 .…”