Aim: To evaluate preventative effects of glutamine in an animal model of gut ischemia/reperfusion (I/R).
Methods: Male Wistar rats were housed in a controlled environment and allowed access to food and water ad libitum. Twenty male Wistar rats were divided into four experimental groups: (1) control group (control) - rats underwent exploratory laparotomy; (2) control + glutamine group (control-GLU) - rats were subjected to laparotomy and treated intraperitoneally with glutamine 24 and 48 h prior to surgery; (3) I/R group - rats were subjected to occlusion of the superior mesenteric artery for 30 min followed by 15 min of reperfusion; and (4) ischemia/reperfusion + glutamine group (G + I/R) - rats were treated intraperitoneally with glutamine 24 and 48 h before I/R. Local and systemic injuries were determined by evaluating intestinal and lung segments for oxidative stress using lipid peroxidation and the activity of superoxide dismutase (SOD), interleukin-6 (IL-6) and nuclear factor kappa beta (NF-κB) after mesenteric I/R.
Results: Lipid peroxidation of the membrane was increased in the animals subjected to I/R (P < 0.05). However, the group that received glutamine 24 and 48 h before the I/R procedure showed levels of lipid peroxidation similar to the control groups (P < 0.05). The activity of the antioxidant enzyme SOD was decreased in the gut of animals subjected to I/R when compared with the control group of animals not subjected to I/R (P < 0.05). However, the group that received glutamine 24 and 48 h before I/R showed similar SOD activity to both control groups not subjected to I/R (P < 0.05). The mean area of NF-κB staining for each of the control groups was similar. The I/R group showed the largest area of staining for NF-κB. The G + I/R group had the second highest amount of staining, but the mean value was much lower than that of the I/R group (P < 0.05). For IL-6, control and control-GLU groups showed similar areas of staining. The I/R group contained the largest area of IL-6 staining, followed by the G + I/R animals; however, this area was significantly lower than that of the group that underwent I/R without glutamine (P < 0.05).
Conclusion: These results demonstrate that pretreatment with glutamine prevents mucosal injury and improves gut and lung recovery after I/R injury in rats.
Keywords: Glutamine; Interleukin 6; Ischemia-reperfusion; Lipid peroxidation; Nuclear factor-kappa beta; Superoxide dismutase.