Effect of ozone on intestinal recovery following intestinal ischemia-reperfusion injury in a rat

Growing evidence suggests that ozone (O-3) protects the host against pathological conditions mediated by reactive oxygen species by increasing the activity of antioxidant enzymes. The purpose of the present study was to examine the effect of O-3 on intestinal recovery and enterocyte turnover after intestinal ischemia-reperfusion (IR) injury in rats. Male Sprague-Dawley rats were divided into four experimental groups: (1) sham rats underwent laparotomy; (2) sham-O-3 rats underwent laparotomy and were treated with an ozone/oxygen mixture intraperitoneally and intraluminally (50 %/50 %); (3) IR rats underwent occlusion of both superior mesenteric artery and portal vein for 20 min followed by 48 h of reperfusion, and (4) IR-O-3 rats underwent IR and were treated with an ozone/oxygen mixture similar to group 2. Intestinal structural changes, Park's injury score, enterocyte proliferation and enterocyte apoptosis were determined 48 h following IR. Western blot was used to determine ERK and Bax protein levels. A non-parametric Kruskal-Wallis ANOVA test was used for statistical analysis with p < 0.05 considered statistically significant. Treatment of IR rats with O-3 resulted in a significant increase in mucosal weight in jejunum (70 %) and ileum (32 %), mucosal DNA (twofold increase) and protein (35 %) in ileum, villus height and crypt depth in jejunum (61 and 16 %, correspondingly) and ileum (31 and 43 %, correspondingly) compared to IR animals. IR-O-3 rats also had a significantly lower intestinal injury score as well as a lower apoptotic index in jejunum and ileum compared and IR animals. A significant increase in cell proliferation rates in IR-O-3 animals was accompanied by increased levels of p-ERK protein. Treatment with ozone prevents intestinal mucosal damage, stimulates cell proliferation and inhibits programmed cell death following intestinal IR in a rat.