Project description:Ischemic stroke can be classified depending on its etiology as cardioembolic (CE), large-vessel atheroesclerotic (LAA), lacunar, other or cryptogenic. Our aim was to identify gene expression changes that could differentiate CE and LAA stroke in order to guide the optimal secondary treatment .
Project description:The proteome of cerebral thrombi from patients recanalized by mechanical thrombectomy in an acute phase of stroke was carried out to determine biomarkers of stroke radio-clinical outcomes for stroke physicians (clinical outcome and mortality at 3 months, intracranial hemorrhagic transformation, etc.). Proteome of cerebral thrombi was also used to elucidate stroke physiopathology (paradoxical effect of glucose in acute phase of stroke) and evaluate recanalization treatments (intravenous thrombolysis by rt-PA and/or thrombectomy efficiency). Retro-MATISSE (Molecular Analysis of Thrombus in Ischemic Stroke prognosiS and Etiology) database was incremented by proteomic analyses of cerebral thrombi successfully retrieved from all consecutive stroke patients (n=47) with large vessel occlusion treated by mechanical thrombectomy in acute phase between December 2020 and May 2021 in the intensive care stroke unit of the University Hospital of Marseille (France).
Project description:We performed a genome-wide methylation study in whole-blood DNA from 404 ischemic stroke patient cohort, distributed across 3 ischemic stroke subtypes: Large-artery atherosclerosis (n=132), Small-artery disease (n=141) and Cardio embolic (n=127) . Illumina HumanMethylation450 BeadChip array was used to measure DNA methylation in CpG sites. We performed a genome-wide methylation study in whole-blood DNA from 185 ischemic stroke patient cohort. Illumina HumanMethylation450 BeadChip array was used to measure DNA methylation in CpG sites.
Project description:It has been unclear whether ischemic stroke induces neurogenesis or neuronal DNA-rearrangements in the human neocortex. We show here that neither is the case, using immunohistochemistry, transcriptome-, genome- and ploidy-analyses, and determination of nuclear bomb test-derived 14C-concentration in neuronal DNA. A large proportion of cortical neurons display DNA-fragmentation and DNA-repair short time after stroke, whereas neurons at chronic stages after stroke show DNA-integrity, demonstrating the relevance of an intact genome for survival. Analyze of potential fusion transcripts in 13 samples, seven cortical ischemic stroke tissue and six control cortex, by deep sequencing using Illumina HiSeq 2000
Project description:Stroke remains a major leading cause of death and disability worldwide. Despite continuous advances, the identification of key molecular signatures of ischemic stroke within the hyper-acute phase of the disease is still of primary interest for a real translational research on stroke diagnosis, prognosis and treatment. High-throughput - omics technologies are enabling large-scale studies on stroke pathology at different molecular levels. Data integration resulting from these -omics approaches is becoming crucial to unravel the interactions among all different molecular elements and highly contribute to interpret all findings in a complex biological context. Here, we have used advanced data integration methods for multi-level joint analysis of transcriptomics and proteomics datasets depicted from the mouse brain 2h after cerebral ischemia. By modeling network-like correlation structures, we identified a set of differentially expressed genes and proteins by ischemia with a relevant association in stroke pathology. The ischemia-induced deregulation of 10 of these inter-correlated elements was successfully verified in a new cohort of ischemic mice, and changes in their expression pattern were also evaluated at a later time-point after cerebral ischemia. Of those, CLDN20, GADD45G, RGS2, BAG5 and CTNND2 were highlighted and evaluated as potential blood biomarkers of cerebral ischemia in blood samples from ischemic and sham-control mice and from ischemic strokes and other patients presenting stroke-mimicking conditions. Our findings indicated that CTNND2 and GADD45G levels in blood within the first hours after ischemic stroke might be potentially useful to discriminate ischemic strokes from mimics and to predict patients’ poor outcome after stroke, respectively. In summary, we have here used for the first time an integrative approach to elucidate by means of biostatistical tools key elements of the initial stages of the stroke pathophysiology, highlighting new outstanding proteins that might be further considered as blood biomarkers of ischemic stroke.
Project description:The purpose of this project was to elucidate gene expression in the peripheral whole blood of acute ischemic stroke patients to identify a panel of genes for the diagnosis of acute ischemic stroke. Peripheral blood samples were collected in Paxgene Blood RNA tubes from stroke patients who were >18 years of age with MRI diagnosed ischemic stroke and controls who were non-stroke neurologically healthy. The results suggest a panel of genes can be used to diagnose ischemic stroke, and provide information about the biological pathways involved in the response to acute ischemic stroke in humans. Total RNA extracted from whole blood in n=39 ischemic stroke patients compared to n=24 healthy control subjects.
Project description:The strains, C57BL6/J, C3H/HeJ, and WSB/EiJ, show a similar collateral vessel anatomy but differ infarct volume after ischemic stroke induction. To identify a gene(s) exhibiting differential gene expression, we performed RNA seq experiment within these mouse strains.
Project description:The current treatment options for ischemic stroke aim to achieve reperfusion but are time critical. Novel therapeutic approaches that can be given beyond the limited time window of 3 - 4.5 hours are still an unmet need to be addressed to improve stroke outcome. The lack of oxygen and glucose in the area of ischemic injury initiates a pathological cascade leading to blood-brain barrier (BBB) breakdown, inflammation and neuronal cell death, a process that may be intercepted to limit stroke progression. Pericytes located at the blood/brain interface are one of the first responders to hypoxia in stroke and therefore a potential target cell for early stroke interventions. Using single-cell RNA sequencing in a mouse model of permanent middle cerebral artery occlusion, we investigated the temporal differences in transcriptomic signatures in pericytes at 1, 12, and 24 hours after stroke compared to the contralateral hemisphere. Our results reveal a stroke-specific subcluster of pericytes that is present at 12 and 24 hours and characterized by the upregulation of genes mainly related to cytokine signalling and immune response. This study identifies temporal transcriptional changes in the acute phase of ischemic stroke that reflect the early response of pericytes to the ischemic insult and its secondary consequences and may constitute potential future therapeutic targets.
Project description:Background: Previous study showed that stroke may be a potential first sign of neoplasia. But the relationship between them remains unclear. Besides, ischemic stroke is a complex brain disease, which involves cell death or complex immune regulation. Thus, it is necessary to reveal the association of tumor immune microenvironment and cell death with ischemic stroke. Methods: Here, a photothrombosis-induced ischemic injury models of brain and skull was established. We compared and analyzed the pattern of gene expression profile between brain and skull after ischemic injury by transcriptome analysis. Further, we investigated the enrichment of relevant differential genes in cancer pathways and cell death pathways, and analyzed changes in the immune microenvironment after ischemic injury. Moreover, the pan-cancer genomic and prognosis analysis of ischemic injury related gene set were performed. Results: The results showed that the gene expression patterns were different in temporal and spatial locations after ischemic injury. We found that the effect on the transcriptome of the brain after skull ischemic injury was particularly large, but it could be recovered in a short period, while the effect on the skull after brain ischemic injury was long-lasting. The expression of genes related to ischemic injury is also associated with cell death and cancer hallmark pathways. In addition, changes in the abundance of immune cells indicate that brain ischemic injury may disrupt its immune microenvironment for a longer time, while skull can better balance the stability of immune microenvironment. Moreover, the brain ischemic injury-related gene sets are highly correlated with a variety of tumors, especially GBM, KIRC, LGG and UVM after stroke have a greater risk of death. Conclusion: This study gives us a new understanding of the role of the skull in brain ischemic injury, and reveals the association of tumor immune microenvironment and cell death with ischemic stroke.