Higashi Youichirou, Aratake Takaaki, Shimizu Shogo, Shimizu Takahiro, Saito Motoaki
Department of Pharmacology, Kochi Medical School, Kochi University.
Nihon Yakurigaku Zasshi. 2021;156(1):21-25. doi: 10.1254/fpj.20069.
Ischemic stroke is one of the most prevalent brain disorders and the major cause of long-term disability. In particularly, hippocampal injury after ischemia-reperfusion is a serious problem as it contributes to vascular dementia. Many researches have revealed that ischemia-reperfusion causes increase in reactive oxygen species production and disruption of neuronal Zn homeostasis in the hippocampus, which induces hippocampal neuron death. Glutathione (GSH) is present in all mammalian cells and plays a crucial role in neuronal cell defense against oxidative stress. On the other hand, thiol group of GSH chemically chelates Zn and functions as a regulator of neuronal Zn homeostasis. These evidences suggest that neuronal GSH levels could be an important factor affecting neuronal surviving. The synthesis of GSH is largely influenced by intracellular cysteine availability. In neurons, excitatory amino acid carrier type 1 (EAAC1) acts as a cysteine transporter and provides cysteine substrate for GSH synthesis. Recently, several animal studies have revealed that promotion of neuronal GSH synthesis through EAAC1 reduces ischemia-induced hippocampal neuron death. This review aims to describe neuroprotective role of GSH against hippocampal injury following ischemia-reperfusion, focusing on EAAC1.
缺血性中风是最常见的脑部疾病之一,也是导致长期残疾的主要原因。特别是,缺血再灌注后的海马损伤是一个严重问题,因为它会导致血管性痴呆。许多研究表明,缺血再灌注会导致海马中活性氧生成增加和神经元锌稳态破坏,从而诱导海马神经元死亡。谷胱甘肽(GSH)存在于所有哺乳动物细胞中,在神经元细胞抵御氧化应激中起关键作用。另一方面,GSH的巯基通过化学方式螯合锌,并作为神经元锌稳态的调节剂发挥作用。这些证据表明,神经元GSH水平可能是影响神经元存活的重要因素。GSH的合成在很大程度上受细胞内半胱氨酸可用性的影响。在神经元中,兴奋性氨基酸转运体1(EAAC1)作为半胱氨酸转运体,为GSH合成提供半胱氨酸底物。最近,一些动物研究表明,通过EAAC1促进神经元GSH合成可减少缺血诱导的海马神经元死亡。本综述旨在描述GSH对缺血再灌注后海马损伤的神经保护作用,重点关注EAAC1。