Role of nuclear receptor coactivator 4-mediated ferritinophagy in intestinal ischemia-reperfusion injury in mice: relationship with ferroptosis / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the role of nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy in intestinal ischemia-reperfusion (I/R) injury in mice and the relationship with ferroptosis.Methods:Thirty SPF-grade healthy male C57BL/6 mice, aged 8-10 weeks, weighing 21-25 g, were divided into 5 groups ( n=6 each) using a random number table method: sham operation group (Sham group), intestinal I/R group (I/R group), intestinal I/R + NCOA4 silencing group (I/R+ NCOA4 shRNA group), intestinal I/R + autophagy inhibitor 3-methyladenine (3-MA) group (I/R+ 3-MA group), and intestinal I/R + NCOA4 silencing + autophagy activator rapamycin (RAPA) group (I/R+ NCOA4 shRNA + RAPA group). The intestinal I/R injury model was developed by clamping the superior mesenteric artery for 45 min followed by reperfusion in anesthetized animals.At 2 weeks before developing the model, AAV-NCOA4-shRNA 1×10 11 vp was injected via the tail vein in group I/R+ NCOA4 shRNA and group I/R+ NCOA4 shRNA+ RAPA, and AAV shCtrl (adenovirus control) 1 x10 11 vp was injected in Sham, I/R and I/R+ 3-MA groups.Rapamycin 4 mg/kg was intraperitoneally injected once a day starting from 7 days before developing the model in group I/R+ NCOA4 shRNA+ RAPA.In group I/R+ 3-MA, 3-MA 10 mg/kg was intraperitoneally injected at 1 h before developing the model.The animals were sacrificed at 2 h of reperfusion, and intestinal tissues were obtained for determination of contents of malondialdehyde (MDA), glutathione (GSH) and Fe 2+ (by colorimetry), contents of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) (by enzyme-linked immunosorbent assay), and expression of NCOA4, microtubule-associated protein 1 light chain 3 (LC3), long-chain fatty acyl-CoA synthase 4 (ACSL4), ferritin heavy chain 1 (FTH1) and glutathione peroxidase 4 (GPX4) (by Western blot). The LC3Ⅱ/LC3Ⅰ ratio was calculated.Intestinal damage was assessed and scored according to Chiu. Results:Compared with group Sham, the Chiu′s score and contents of MDA, Fe 2+ , TNF-α and IL-1β were significantly increased, GSH content was decreased, the expression of NCOA4 and ACSL4 was up-regulated, LC3Ⅱ/LC3Ⅰ ratio was increased, and the expression of GPX4 and FTH1 was down-regulated in group I/R ( P<0.05). Compared with group I/R, the Chiu′s score and contents of MDA, Fe 2+ , TNF-α and IL-1β were significantly decreased, and GSH content was increased in I/R+ NCOA4 shRNA and I/R+ 3-MA groups, the expression of NCOA4 and ACSL4 was significantly down-regulated, and the expression of GPX4 and FTH1 was up-regulated in group I/R+ NCOA4 shRNA ( P<0.05), and ACSL4 expression was significantly down-regulated, LC3Ⅱ/LC3Ⅰ ratio was decreased, and the expression of GPX4 and FTH1 was up-regulated in group I/R+ 3-MA ( P<0.05). Conclusions:NCOA4-mediated ferritinophagy can promote ferroptosis, which is involved in the pathophysiological mechanism of intestinal I/R injury in mice.