Ischemia/reperfusion is a key feature of acute ischemic stroke, which causes neuron dysfunction and death. Exosomes, small extracellular vesicles produced by most cell types, are implicated in the mediation of cellular interactions with their environment. Here, we investigated the contents and functions of exosomes from neurons under ischemic reperfusion injury. First, rat cortical primary neuronal cell cultures were placed in an oxygen- and glucose-deprived (OGD) medium, followed by reperfusion in a normoxic conditioned medium (OGD/R) to mimic ischemia/reperfusion in vitro. The neuron-derived exosomes were harvested from the conditioned medium under normoxia and OGD/R. Through next-generation sequencing, exosomal miRNA expression levels in normoxic and OGD/R condition were compared. Their functional activity in terms of neuron viability and quantitative analysis of neurite outgrowth were examined. The expression levels of 45 exosomal miRNAs were significantly different between normoxic and OGD/R conditions. Bioinformatics analysis of dysregulated exosomal miRNAs identified multiple pathways involved in cell survival and death processes and neuronal signaling. Moreover, treatment with exosomes from OGD/R to cultured cortical neurons significantly impaired neuronal cell viability and reduced neurite outgrowth in terms of the number of primary or total neurites as well as length of primary neurites, compared with exosomes from normoxic conditions. miRNA-packed exosomes released by neurons under OGD/R challenge may contribute to post ischemic neuronal injury and provide further understanding of the effect of stressed neurons on neighboring neuronal functions.

缺血/再灌注是急性缺血性中风的一个关键特征，会导致神经元功能障碍和死亡。外泌体是大多数细胞类型产生的小细胞外囊泡，与细胞与其环境的相互作用有关。在这里，我们研究了缺血再灌注损伤下神经元外泌体的内容和功能。首先，将大鼠皮质原代神经元细胞培养物置于缺氧和缺糖 (OGD) 培养基中，然后在常氧条件培养基 (OGD/R) 中再灌注以模拟体外缺血/再灌注。在常氧和 OGD/R 下从条件培养基中收获神经元衍生的外泌体。通过二代测序，比较了常氧和 OGD/R 条件下的外泌体 miRNA 表达水平。检查了它们在神经元活力和神经突生长的定量分析方面的功能活动。45 种外泌体 miRNA 的表达水平在常氧和 OGD/R 条件下存在显着差异。失调的外泌体 miRNA 的生物信息学分析确定了涉及细胞存活和死亡过程以及神经元信号传导的多种途径。此外，与常氧条件下的外泌体相比，OGD/R 外泌体对培养的皮层神经元的处理显着损害了神经元细胞的活力，并在初级或总神经突的数量以及初级神经突的长度方面减少了神经突的生长。