神经元来源细胞外囊泡促进神经干细胞的神经生成

Neuron-derived extracellular vesicles promote neurogenesis of neural stem cells

背景:已有研究表明,神经干细胞能够分化为神经元、星形胶质细胞和少突胶质细胞等。间充质干细胞来源细胞外囊泡被证实能够透过血脑屏障到达中枢神经损伤部位,促进神经修复。然而,神经元来源细胞外囊泡是否促进神经干细胞向有益于神经生成的方向分化,帮助神经修复,还不是很明确。目的:探究神经元来源细胞外囊泡是否有利于神经干细胞向神经生成的方向分化。方法:用胰酶消化法从新生SD大鼠大脑皮质中提取神经元和神经干细胞。收集培养神经元的细胞上清,提取神经元来源细胞外囊泡。将培养10 d的神经干细胞与神经元来源细胞外囊泡或PBS共培养7 d,采用免疫印迹、免疫荧光和RT-qPCR技术分别检测神经元、神经干细胞、少突胶质细胞和星形胶质细胞特异性标志蛋白的表达。结果与结论:神经干细胞与神经元来源细胞外囊泡共培养后,高表达神经元特异性蛋白β3微管蛋白、神经丝蛋白200和少突胶质细胞特异性蛋白髓鞘碱性蛋白,低表达星形胶质细胞特异性标志蛋白胶质纤维酸性蛋白。这些结果说明,神经元来源细胞外囊泡能够促进神经干细胞向神经元和少突胶质细胞分化,抑制其向星形胶质细胞分化。

BACKGROUND:It has been shown that neural stem cells can differentiate into neurons,astrocytes,and oligodendrocytes.Mesenchymal stem cells-derived extracellular vesicles have also been shown to cross the blood-brain barrier to reach sites of central nervous injury and promote neural repair.However,it is not clear whether neuron-derived extracellular vesicles promote the differentiation of neural stem cells in a direction that is beneficial for neurogenesis.OBJECTIVE:To investigate whether neuron-derived extracellular vesicles facilitate neural stem cell differentiation towards neurogenesis.METHODS:Neurons and neural stem cells were extracted from neonatal SD rat cerebral cortex by trypsin digestion.Cell supernatants of neurons were collected.Neuron-derived extracellular vesicles were extracted.Neural stem cells cultured for 10 days were co-cultured with neuron-derived extracellular vesicles or PBS for 7 days.Immunoblotting,immunofluorescence,and RT-qPCR were used to detect proteins specifically expressed by neurons,neural stem cells,oligodendrocytes,and astrocytes.RESULTS AND CONCLUSION:The neural stem cells co-cultured with neuron-derived extracellular vesicles showed high expression of neuron-specific proteins and oligodendrocyte-specific proteins includingβ3-tubulin,neurofilament 200 and myelin basic protein,and low expression of astrocyte-specific protein glial fibrillary acidic protein.These results suggest that neuron-derived extracellular vesicles can promote the differentiation of neural stem cells into neurons and oligodendrocytes and prevent the differentiation of neural stem cells into astrocytes.