Department of Neurosurgery, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu Province, China.
Department of Neurosurgery, Yijishan Hospital, Wannan Medical College, Wuhu, Anhui Province, China.
Life Sci. 2020 Sep 15;257:118050. doi: 10.1016/j.lfs.2020.118050. Epub 2020 Jul 4.
Early brain injury is an essential pathological process after subarachnoid hemorrhage (SAH), with many cell death modalities. Ferroptosis is a newly discovered regulated cell death caused by the iron-dependent accumulation of lipid peroxidation, which can be prevented by glutathione peroxidase 4 (GPX4). Our study aimed to investigate the role of GPX4 in neuronal cell death after experimental SAH.
In vivo experimental SAH was induced by injecting autologous arterial blood into the prechiasmatic cistern in male Sprague-Dawley rats. Meanwhile, the in vitro SAH model was performed with primary rat cortical neurons cultured in medium containing hemoglobin (Hb). Adenovirus was used to overexpress GPX4 before experimental SAH. GPX4 expression was detected by western blot and immunofluorescence experiments. Malondialdehyde (MDA) was measured to evaluate the level of lipid peroxidation. Nissl staining was employed to assess cell death in vivo, whereas lactate dehydrogenase (LDH) release was used to evaluate cell damage in vitro. The brain water content and neurological deficits were evaluated to determine brain injury.
Endogenous GPX4 was mainly expressed in neurons, and its expression decreased at 24 h after experimental SAH. Overexpression of GPX4 significantly reduced lipid peroxidation and cell death in the experimental SAH models both in vivo and in vitro. Moreover, overexpression of GPX4 ameliorated brain edema and neurological deficits at 24 h after SAH.
The decrease of GPX4 expression potentially plays an important role in ferroptosis during early brain injury after SAH. Overexpression of GPX4 has a neuroprotective effect after SAH.
蛛网膜下腔出血(SAH)后早期脑损伤是一种重要的病理过程,存在多种细胞死亡方式。铁死亡是一种新发现的受铁依赖性脂质过氧化积累调控的细胞死亡,可被谷胱甘肽过氧化物酶 4(GPX4)所抑制。本研究旨在探讨 GPX4 在实验性 SAH 后神经元细胞死亡中的作用。
雄性 Sprague-Dawley 大鼠通过将自体动脉血注入视交叉前池来诱导体内实验性 SAH。同时,在含有血红蛋白(Hb)的培养基中培养原代大鼠皮质神经元来建立体外 SAH 模型。在实验性 SAH 前,用腺病毒过表达 GPX4。通过 Western blot 和免疫荧光实验检测 GPX4 的表达。通过测定丙二醛(MDA)来评估脂质过氧化水平。通过尼氏染色评估体内细胞死亡,通过测定乳酸脱氢酶(LDH)释放来评估体外细胞损伤。通过脑水含量和神经功能缺损评估来确定脑损伤。
内源性 GPX4 主要在神经元中表达,在实验性 SAH 后 24 h 表达下降。在体内和体外实验性 SAH 模型中,过表达 GPX4 可显著减少脂质过氧化和细胞死亡。此外,过表达 GPX4 可改善 SAH 后 24 h 的脑水肿和神经功能缺损。
GPX4 表达的降低可能在 SAH 后早期脑损伤的铁死亡中起重要作用。过表达 GPX4 在 SAH 后具有神经保护作用。