Abstract TP130: Transcriptome Analysis of Mononuclear Cell Responses After Ischemic Stroke in Type 2 Diabetic Mice

Abstract

Introduction: Type 2 diabetes mellitus (T2DM) is a major risk factor of ischemic stroke and is associated with poor outcome after stroke. However, the mechanisms underlying the detrimental effects of diabetes are largely unclear. We used single-cell RNA sequencing (scRNA seq) to determine the transcriptome profiles of blood peripheral mononuclear cells (BPMNs) under diabetic and ischemic conditions using T2DM mouse model. Hypothesis: The altered gene expression under diabetic condition affects the normal differentiation of BPMNs, resulting in the aggravation of ischemic brain injury. Methods: We performed scRNA seq for BPMNs from four groups of mice, consisting of db/db mice with or without stroke and db/+ mice with or without stroke. Stroke was induced by distal middle cerebral artery occlusion. We specified the cell types of BPMNs and compared the transcriptome among the groups of mice. We assessed the biological role of identified differentially expressed genes (DEGs) by enrichment analysis. Results: In the comparison between db/db and db/+ groups, 168 up-regulated and 245 down-regulated DEGs were identified. The db/db group was composed of a larger population of macrophages and a smaller population of lymphocytes compared to db/+ group. The gene Cebpa , known to be associated with myeloid maturation, was significantly down-regulated in monocytes/macrophages, indicating the adverse effect of diabetes on the normal differentiation of myeloid cells. In addition, enrichment analysis revealed that up-regulated DEGs were related to the gene ontology term translation in B cells and innate immune response in monocytes. On the other hand, the down-regulated DEGs were related to antigen processing and presentation in macrophages. In the comparison between stroke and non-stroke groups, 21 up-regulated and 223 down-regulated DEGs were identified, in which down-regulated DEGs were related to cellular oxidant detoxification in T cells. Conclusions: The present study demonstrated altered gene expression profile and molecular network across various cell types in PBMCs in response to diabetic and ischemic conditions by scRNAseq, providing a clue to the underlying mechanism of the adverse effect of T2DM on native immunity and response to stroke.