Cao Cheng, Lu Ting, Cheng Qian, Cui Gang, Wang Zhong, Li Xiang, Li Haiying, Gao Heng, Shen Haitao, Sun Qing
Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu Province, China; Department of Intensive Care Unit, The Affiliated Jiangyin Hospital of Nantong University, Jiangyin City 214400, Jiangsu Province, China; Department of Brain Center, The Affiliated Jiangyin Hospital of Nantong University, Jiangyin City 214400, Jiangsu Province, China.
Department of Neurosurgery & Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, Jiangsu Province, China.
Brain Res. 2023 Dec 1;1820:148556. doi: 10.1016/j.brainres.2023.148556. Epub 2023 Aug 28.
Ferroptosis is an important therapeutic target to alleviate early brain injury (EBI) after subarachnoid hemorrhage (SAH), yet the mechanism of neuronal ferroptosis after SAH remains unclear. System xc- dysfunction is one of the key pathways to induce ferroptosis. System xc- activity is mainly regulated by the expression of xCT. This study was designed to investigate the effect of xCT expression and System xc- activity on ferroptosis and EBI in an experimental SAH model both in vitro and in vivo.
SAH was induced in adult male Sprague-Dawley rats by injecting autologous blood into the prechiasmatic cistern. Primary neurons treated with oxyhemoglobin (10 µM) were used to mimic SAH in vitro. Plasmid transfection was used to induce xCT overexpression. Western blotting, immunofluorescence staining, measurement of cystine uptake, enzyme-linked immunosorbent assay, transmission electron microscopy, Nissl staining, and a series of neurobehavioral tests were conducted to explore the role of xCT and System xc- activity in ferroptosis and EBI after SAH.
We found that System xc- dysfunction induced ferroptosis and exacerbated EBI after SAH in rats. xCT deficiency after SAH resulted in System xc- dysfunction, weakened neuronal antioxidant capacity and activated neuronal ferroptosis. xCT overexpression improved neuronal antioxidant capacity and inhibited neuronal ferroptosis by restoring System xc- activity. Rats with xCT overexpression after SAH presented with attenuated brain edema and inflammation, increased neuronal survival, and ameliorated neurological deficits.
Our study revealed that restoring System xc- activity by xCT overexpression inhibited neuronal ferroptosis and EBI and improved neurological deficits after SAH.
铁死亡是减轻蛛网膜下腔出血（SAH）后早期脑损伤（EBI）的一个重要治疗靶点，但SAH后神经元铁死亡的机制仍不清楚。系统xc-功能障碍是诱导铁死亡的关键途径之一。系统xc-活性主要受xCT表达的调节。本研究旨在探讨xCT表达和系统xc-活性对实验性SAH模型体外和体内铁死亡及EBI的影响。
通过将自体血注入视交叉前池，在成年雄性Sprague-Dawley大鼠中诱导SAH。用氧合血红蛋白（10µM）处理的原代神经元在体外模拟SAH。采用质粒转染诱导xCT过表达。进行蛋白质免疫印迹、免疫荧光染色、胱氨酸摄取量测定、酶联免疫吸附测定、透射电子显微镜检查、尼氏染色以及一系列神经行为测试，以探讨xCT和系统xc-活性在SAH后铁死亡和EBI中的作用。
我们发现系统xc-功能障碍在大鼠SAH后诱导铁死亡并加重EBI。SAH后xCT缺乏导致系统xc-功能障碍，削弱神经元抗氧化能力并激活神经元铁死亡。xCT过表达通过恢复系统xc-活性提高神经元抗氧化能力并抑制神经元铁死亡。SAH后xCT过表达的大鼠脑水肿和炎症减轻，神经元存活率增加，神经功能缺损改善。
我们的研究表明，通过xCT过表达恢复系统xc-活性可抑制SAH后神经元铁死亡和EBI，并改善神经功能缺损。
