Data_Sheet_2_Sevoflurane exposure causes neuronal apoptosis and cognitive dysfunction by inducing ER stress via activation of the inositol 1, 4, 5-trisphosphate receptor.ZIP

The role of the inositol 1, 4, 5-trisphosphate receptor (IP3R) in hippocampal neuronal apoptosis and cognitive dysfunction induced by sevoflurane is currently unclear. Therefore, in this study, we investigated the role of the IP3R in endoplasmic reticulum (ER) stress and hippocampal neuronal apoptosis induced by sevoflurane in aged rats and isolated hippocampal neurons using both in vivo and in vitro experiments, including bioinformatics, functional enrichment analysis, gene set enrichment analysis, hematoxylin, and eosin staining, TUNEL assay, flow cytometry, western blot analysis and transmission electron microscopy. Furthermore, behavioral assessment was performed with the Morris water maze test. We identified 232 differentially expressed genes induced by sevoflurane exposure, including 126 upregulated genes and 106 downregulated genes. Sevoflurane exposure caused cognitive impairment and neuronal injury, and increased p-IP3R levels and ER stress. An IP3R inhibitor, 2-APB, suppressed these changes, while an IP3R agonist, FK-506, aggravated these changes. Together, these findings suggest that sevoflurane exposure causes marked cognitive dysfunction in aged rats and neuronal injury in isolated hippocampal neurons by activating the IP3R and inducing cytoplasmic calcium overload, thereby resulting in ER stress and hippocampal neuronal apoptosis.
GRAPHICAL ABSTRACT

目前，肌醇1,4,5-三磷酸受体（inositol 1,4,5-trisphosphate receptor, IP3R）在七氟烷诱导的海马神经元凋亡及认知功能障碍中的作用尚不明确。因此，本研究通过体内外实验，包括生物信息学分析、功能富集分析、基因集富集分析、苏木精-伊红染色、TUNEL检测、流式细胞术、蛋白质印迹分析以及透射电子显微镜技术，探讨了IP3R在老龄大鼠及分离培养的海马神经元中参与七氟烷诱导的内质网（endoplasmic reticulum, ER）应激与海马神经元凋亡的作用。此外，本研究采用莫里斯水迷宫实验开展行为学评估。本研究共筛选得到七氟烷暴露诱导的232个差异表达基因，其中上调基因126个，下调基因106个。七氟烷暴露可引发认知功能损伤与神经元损伤，并升高p-IP3R水平及内质网应激水平。IP3R抑制剂2-APB可抑制上述变化，而IP3R激动剂FK-506则可加重上述病理改变。综上，本研究结果表明，七氟烷暴露可通过激活IP3R并诱导胞质钙超载，进而引发内质网应激与海马神经元凋亡，最终导致老龄大鼠出现显著认知功能障碍，并对分离培养的海马神经元造成损伤。
图文摘要