The evaluation of possible anti-inflammatory and anti-apoptotic effects of humanin in a rat model of intestinal ischemia/reperfusion injury

Intestinal ischemia/reperfusion (I/R) injury can be seen during/after mesenteric artery embolism, severe trauma, major vascular and abdominal procedures. High mortality rates have been reported, especially after acute mesenteric ischemia. Anti-apoptotic, anti-inflammatory and anti-oxidative effects of humanin (HN) have been demonstrated in in vitro and in vivo studies. HNG is an analog obtained by serine/glycine substiation at the 14th position of HN and its cytoprotective effect is greater. There is no published study on the effects of HN on intestinal I/R injury. The effect of HNG on experimental intestinal I/R injury was investigated in this study. The study was performed in 4 groups as 8 rats in each group. Superior mesenteric artery (SMA) was dissected in all groups. No additional treatment was performed in the control group (Group K) and a sample of small intestine tissue was taken at the 3rd hour. In the I/R group, small intestine tissue samples were taken after SMA clamping for 60 min and then 120 min reperfusion. Unlike I/R group, group 3rd was given intraperitoneal HNG 2 mg/kg dose 1 hour before ischemia (Group HIR). Group 4 was additionally administered intraperitoneally with HNG 2 mg /kg dose 10 minutes before reperfusion (Group HIHR). In histopathological evaluation, Chiu's mucosal ischemia scale was used to determine reperfusion damage. Apoptotic cell count was used in the evaluation of apoptosis. Tissue superoxide dismutase (SOD) activity and advanced oxidation protein products (AOPP) levels were used in biochemical analysis. A value of p <0.05 was considered significant. Although the mucosal damage was decreased in the HIR and HIHR groups compared to the I/R group, the difference was not statistically significant (p=0,088). Anti-apoptotic effect was observed in HIR and HIRR groups, but statistically significant difference was observed in only comparison of HIRR and I/R groups (p<0.05). There was no significant difference between groups in terms of SOD and AOPP levels (p=0.620/p=0.690). In this study, we observed that HNG had cytoprotective effects in preventing I/R injury, but the difference did not reach statistical significance. The effects of HN on intestinal I/R injury should be studied in larger sample groups.