Endoplasmic reticulum stress promotes ferroptosis and aggravates cerebral ischemia-reperfusion injury

Zhang Yueting; Li Jinglin; Fu Zhenyi; Yan Fei; Gao Yu; Liu Jiaxin

doi:10.12307/2026.038

Abstract：BACKGROUND:Embolization of cerebral arteries leads to cerebral tissue ischemia and hypoxia.Restoration of blood flow and reoxygenation usually results in cerebral ischemia-reperfusion injury.However,current research on the interaction between ferroptosis and endoplasmic reticulum stress in cerebral ischemia-reperfusion injury is relatively limited. OBJECTIVE:To investigate the roles and mechanisms of endoplasmic reticulum stress and ferroptosis in cerebral ischemia-reperfusion injury. METHODS:The HT-22 cell line was used and divided into four groups.An oxygen glucose deprivation/reperfusion(OGD/R)model was established in the model group.Cells were treated with 1.25 mmol/L 4-PBA(an endoplasmic reticulum stress inhibitor)for 2 hours prior to OGD/R,forming the 4-PBA group.Cells were treated with 1.25 mmol/L 4-PBA and 5 μmol/L CCT020312(a protein kinase RNA-like ER kinase activator)for 2 hours before OGD/R,forming the 4-PBA+CCT group.Cell viability was detected by cell counting kit-8 experiment;western blot was used to detect the expression of ferroptosis-,endoplasmic reticulum stress,and protein kinase RNA-like ER kinase/transcription activating factor 4-related proteins;flow cytometry was used to detect cell apoptosis;and a reagent kit was used to detect the concentration of Fe2+. RESULTS AND CONCLUSION:Compared with the control group,OGD/R treatment significantly suppressed neuronal cell proliferation activity by inducing ferroptosis,endoplasmic reticulum stress and apoptosis mechanisms.Treatment with the endoplasmic reticulum stress inhibitor 4-PBA effectively alleviated ferroptosis,apoptosis and inhibition of cell viability caused by OGD/R.In addition,4-PBA significantly reduced the expression levels of protein kinase RNA-like ER kinase and transcription activating factor 4 induced by OGD/R.The protein kinase RNA-like ER kinase activator CCT020312 reversed the inhibitory effects of 4-PBA on endoplasmic reticulum stress,ferroptosis,apoptosis and cell activity in the OGD/R model.To conclude,endoplasmic reticulum stress promotes ferroptosis through the protein kinase RNA-like ER kinase/transcription activating factor 4 signaling pathway,thereby exacerbating cerebral ischemia-reperfusion injury.