Role of STAT3/NCOA4-mediated ferritinophagy in salidroside-induced attenuation of intestinal ischemia-reperfusion injury in mice: relationship with ferroptosis / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the role of signal transducer and activator of transcription 3 (STAT3)/nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy in salidroside-induced attenuation of intestinal ischemia-reperfusion (I/R) injury in mice and the relationship with ferroptosis.Methods:Thirty-six SPF-grade healthy male C57BL mice, aged 6-8 weeks, weighing 20-25 g, were divided into 6 groups ( n=6 each) by a random number table method: sham operation group (S group), sham operation+ salidroside group (SS group), intestinal I/R group (IR group), intestinal I/R+ salidroside group (IS group), intestinal I/R+ salidroside+ autophagy activator rapamycin group (ISR group) and intestinal I/R+ salidroside+ STAT3 activator colivelin group (ISC group). The intestinal I/R injury model was established by clamping the superior mesenteric artery for 45 min followed by 30-min reperfusion in IR, IS, ISR and ISC groups, while the superior mesenteric artery was only isolated without clipping in S and SS groups. At 1 week before developing the model, salidroside 40 mg/kg was intraperitoneally injected once a day for 7 consecutive days in SS, IS, ISC and ISR groups, rapamycin 4 mg/kg was intraperitoneally injected once a day for 7 consecutive days in group ISR, colivelin 1 mg/kg was intraperitoneally injected once a day for 7 consecutive days in group ISC, while the equal volume of normal saline was given instead in the rest two groups. The mice were sacrificed at 30 min of reperfusion, and intestinal tissues were obtained for examination of the pathological changes after HE staining (with a optical microscope) which were scored according to Chiu and for determination of contents of malondialdehyde (MDA), Fe 2+, glutathione (GSH) and reactive oxygen species (ROS), activity of superoxide dismutase (SOD) and expression of p-STAT3, STAT3, glutathione peroxidase 4 (GPX4), NCOA4 and ferritin heavy chain 1 (FTH1) in intestinal tissues (by Western blot). Results:Compared with group S, the Chiu′s score and contents of MDA, Fe 2+ and ROS were significantly increased, the content of GSH was decreased, the activity of SOD was decreased, the expression of p-STAT3 and NCOA4 was up-regulated, the expression of GPX4 and FTH1 was down-regulated, the p-STAT3/STAT3 ratio was increased ( P<0.05), pathological injury was found in intestinal tissues, and no significant change was found in the aforementioned indexes in group IR( P>0.05). Compared with group IR, the Chiu′s score and contents of MDA, Fe 2+ and ROS were significantly decreased, GSH content was increased, SOD activity was increased, the expression of p-STAT3 and NCOA4 was down-regulated, the expression of GPX4 and FTH1 was up-regulated, p-STAT3/STAT3 ratio was decreased ( P<0.05), and the pathological injury was significantly alleviated in intestinal tissues in group IS. Compared with group IS, the Chiu′s score and contents of MDA, Fe 2+ and ROS were significantly increased, GSH content was decreased, SOD activity was decreased, the expression of p-STAT3 and NCOA4 was up-regulated, the expression of GPX4 and FTH1 was down-regulated, p-STAT3/STAT3 ratio was increased ( P<0.05), and the pathological injury was aggravated in intestinal tissues in ISR and ISC groups. There was no statistically significant difference in the expression of STAT3 among the five groups ( P>0.05). Conclusions:STAT3/NCOA4-mediated ferritinophagy is involved in the process of salidroside-induced reduction of intestinal I/R injury in mice, which may be related to inhibiting ferroptosis.