Enemas with N-acetylcysteine can reduce the level of oxidative damage in cells of the colonic mucosa diverted from the faecal stream

Abstract

Background: Oxidative stress has been related to inflammation of the colonic mucosa in patients with diversion colitis (DC).

Aim: The purpose of this study was to evaluate the antioxidants effects of n-acetylcysteine (NAC) in colon segments without faecal stream.

Methods: Thirty-six Wistar rats were subjected to diversion of the faecal stream by proximal colostomy and a distal mucosal colon fistula. They were distributed into three experimental groups of 12 animals each; the animals in each group underwent daily enemas containing saline solution (control group) or either a 25 or 100 mg/kg dose of NAC (treated groups). In each group, animals were sacrificed after 2 or 4 weeks. The degree of inflammation was determined by histopathological analysis and stratified by inflammatory grading scale. Oxidative DNA damage was measured by comet assay. The Mann-Whitney test and ANOVA were used for statistical analysis; p<0.05 was considered significant.

Results: The oxidative DNA damage in colon segments without faecal stream was significantly lower in animals treated with either concentration of NAC than in control group, regardless of the duration of intervention (p<0.01).

Conclusions: Intrarectal application of NAC reduces the inflammation as well as DNA oxidative damage and could be beneficial as a complementary agent in the treatment of DC.