Abstract
Background Intestinal ischemia-reperfusion (I/R) injury represents a critical clinical condition characterized by oxidative stress, inflammatory activation, and impairment of intestinal mucosal integrity. Although restoration of blood flow is necessary to prevent irreversible tissue damage, reperfusion itself can aggravate injury through complex biochemical and cellular mechanisms. Despite improvements in surgical and intensive care management, effective pharmacological agents capable of reducing intestinal I/R injury remain limited. Carnosine, a naturally occurring dipeptide with antioxidant and anti-inflammatory properties, has been proposed as a potential protective agent in several experimental I/R models. Objective The aim of this study was to determine whether carnosine administration reduces histopathological mucosal injury scores and alters biochemical parameters in a rat model of intestinal I/R injury. Methods We allocated 30 adult Sprague-Dawley rats randomly into three groups (n = 10 each): control, I/R, and I/R + carnosine. Intestinal ischemia was established by clamping of the superior mesenteric artery (SMA) for 60 minutes, followed by 120 minutes of reperfusion. In the treatment group, carnosine (50 mg/kg, intraperitoneally) was administered immediately prior to the reperfusion phase. At the end of the reperfusion period, the animals were sacrificed, and terminal ileum tissue samples, together with intracardiac blood specimens, were collected. Histological injury was evaluated using the Chiu/Park mucosal injury scoring system. Serum malondialdehyde (MDA), blood urea nitrogen (BUN), creatinine (Cr), potassium (K), creatine kinase (CK), and phosphorus (P) levels were analyzed. Results Histopathological injury scores were significantly higher in both ischemic groups compared with the control group (p < 0.05). No statistically significant difference was observed between the I/R and I/R + carnosine groups (p > 0.05). Serum MDA levels were highest in the carnosine-treated group. Conclusion Carnosine did not demonstrate a protective effect against intestinal I/R injury under the conditions of this study. The elevated MDA levels observed in the treatment group further complicate the interpretation of its expected antioxidant effects. Further experimental studies are required to clarify the role of carnosine in intestinal I/R injury.