Evaluation of Endoplasmic Reticulum Stress in an Experimental Intestinal Ischemia-Reperfusion Model in Rats: The Role of Ozone Therapy and Trimetazidine

Aim: The objective of the study was to assess the impact of ozone (O-3) and trimetazidine on the intestines following ischemia-reperfusion (I/R) injury through the investigation of endoplasmic reticulum stress. Methods: Forty Sprague Dawley rats were separated into five groups. The groups were named as follows: control, O-3, I/R, I/R + trimetazidine (TMZ), and I/R + O-3. The control group had laparotomy and exploration of the superior mesenteric artery (SMA) only. Furthermore, alongside laparotomy and SMA exploration, an intraperitoneal (i.p.) administration of a 0.7 mg/kg ozone-oxygen (O-3-O-2) combination was given to the O-3 group. In the experimental groups, the SMA was blocked with the silk suture ligation technique for a duration of 1 h and then restored to normal blood flow for another hour. In the I/R + O-3 group, ozone was delivered i.p. at a dosage of 0.7 mg/kg, 30 min after ischemia. In the I/R + TMZ group, a dose of 20 mg/kg/day of trimetazidine was administered orally via gavage for a duration of 7 days, beginning 1 week prior to the induction of ischemia. Intestinal tissues were taken to assess indicators of intestinal mucosal injury and oxidative stress. Results: The level of the lipid peroxidation marker malondialdehyde (MDA) was significantly reduced in the experimental groups as compared to the I/R group (p < 0.05). The experimental groups had considerably greater levels of glutathione (GSH), which reflects antioxidant capacity, compared to the I/R group (p < 0.05). Nevertheless, the concentration of GSH was observed to be increased in the I/R + O-3 group in comparison to the I/R + TMZ group (p < 0.05). The histopathological damage score showed a substantial decrease in the experimental groups as compared to the I/R group (p < 0.05). The I/R + O3 group had the lowest injury score. The experimental groups exhibited significantly reduced positivity of the endoplasmic reticulum (ER) stress markers C/EBP homologous protein (CHOP) and glucose-regulated protein (GRP)-78 compared to the I/R group (p < 0.05). Conclusions: The findings provide evidence for the potential advantages of utilizing ozone therapy in the treatment of intestinal ischemia-reperfusion injury. Additionally, they propose that ozone should be assessed in more extensive clinical trials in the future as a therapeutic agent that can disrupt endoplasmic reticulum stress.