Table_1_Single-Cell Sequencing Analysis of the db/db Mouse Hippocampus Reveals Cell-Type-Specific Insights Into the Pathobiology of Diabetes-Associated Cognitive Dysfunction.xlsx

Diabetes-associated cognitive decline (DCD), is one of the complications of diabetes, which is characterized by a series of neurophysiological and pathological abnormalities. However, the exact pathogenesis of DCD is still unknown. Single-cell RNA sequencing (scRNA-seq) could discover unusual subpopulations, explore functional heterogeneity and identify signaling pathways and potential markers. The aim of this research was to provide deeper opinion into molecular and cellular changes underlying DCD, identify different cellular types of the diabetic mice hippocampus at single-cell level, and elucidate the factors mediating the pathogenesis of DCD. To elucidate cell specific gene expression changes in the hippocampus of diabetic encephalopathy. Single-cell RNA sequencing of hippocampus from db/m and db/db mice was carried out. Subclustering analysis was performed to further describe microglial cell subpopulations. Interestingly using immunohistochemistry, these findings were confirmed at the protein level. Single cell analysis yielded transcriptome data for 14621 hippocampal cells and defined 11 different cell types. Analysis of differentially expressed genes in the microglia compartments indicated that infection- and immune system process- associated terms, oxidative stress and inflammation play vital roles in the progression of DCD. Compared with db/m mouse, experiments at the protein level supported the activation of microglia, increased expression of inflammatory factors and oxidative stress damage in the hippocampus of db/db mouse. In addition, a major finding of our research was the subpopulation of microglia that express genes related to pro-inflammatory disease-associated microglia (DAM). Our research reveals pathological alterations of inflammation and oxidative stress mediated hippocampal damage in the db/db mice, and may provide potential diagnostic biomarkers and therapeutic interventions for DCD.

糖尿病相关认知功能下降（Diabetes-associated cognitive decline, DCD）是糖尿病的并发症之一，以一系列神经生理与病理异常为特征。然而，DCD的确切发病机制仍未明确。单细胞RNA测序（scRNA-seq）可用于发现罕见细胞亚群、探究功能异质性，并识别信号通路与潜在标志物。本研究旨在深入解析DCD潜在的分子与细胞层面改变，在单细胞水平鉴定糖尿病小鼠海马体的不同细胞类型，并阐明介导DCD发病机制的关键因素，以明确糖尿病脑病小鼠海马体的细胞特异性基因表达变化。本研究对db/db与db/m小鼠的海马体开展了单细胞RNA测序，并通过亚聚类分析进一步解析小胶质细胞亚群。有趣的是，本研究通过免疫组化实验在蛋白层面验证了上述发现。单细胞测序共获得14621个海马细胞的转录组数据，鉴定出11种不同的细胞类型。对小胶质细胞群的差异表达基因分析显示，感染与免疫系统过程相关条目、氧化应激及炎症反应在DCD进展中发挥关键作用。与db/m小鼠相比，蛋白层面实验证实db/db小鼠海马体中小胶质细胞活化、炎症因子表达上调及氧化应激损伤加剧。此外，本研究的一项重要发现是存在一类表达促炎型疾病相关小胶质细胞（disease-associated microglia, DAM）相关基因的小胶质细胞亚群。本研究揭示了db/db小鼠体内炎症与氧化应激介导的海马体损伤病理改变，可为DCD提供潜在的诊断生物标志物与治疗干预靶点。