Gutiérrez Aguilar Germán Fernando, Alquisiras-Burgos Ivan, Espinoza-Rojo Mónica, Aguilera Penélope
Laboratorio de Patología Vascular Cerebral, Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez", Insurgentes Sur #3877, Col. La Fama, Tlalpan, Ciudad de México, 14269, México.
Laboratorio de Biología Molecular y Genómica, Universidad Autónoma de Guerrero, Chilpancingo, Guerrero, 39087, México.
Adv Neurobiol. 2017;16:269-282. doi: 10.1007/978-3-319-55769-4_13.
Excitatory amino acid transporters (EAATs) expressed in astrocytes remove the glutamate released by neurons in and around the synaptic cleft. In this manner, astrocytes preserve the signaling functions mediated by glutamate on synapses and prevent excitotoxicity. Additionally, EAAT activation stimulates glucose utilization in astrocytes, linking neuronal activity with astrocyte metabolism. In this chapter, we briefly review the characteristics of the EAATs and the glucose transporters (GLUTs) expressed in the brain. Thereafter, we focus on the effect of EAATs activation and its association with glucose utilization in astrocytes, specifically addressing the role played by Na and Ca ions. Next, we analyze evidence that proposes mechanisms by which the activity of GLUTs could be modulated after EAAT activation (e.g., kinases altering GLUTs traffic to cell membrane). Finally, we analyzed the current knowledge on EAAT function during energy deficiency as a possible inducer of GLUT expression to prevent neuronal damage.
星形胶质细胞中表达的兴奋性氨基酸转运体(EAATs)可清除突触间隙及其周围神经元释放的谷氨酸。通过这种方式,星形胶质细胞保留了谷氨酸介导的突触信号功能,并防止兴奋性毒性。此外,EAAT激活可刺激星形胶质细胞对葡萄糖的利用,将神经元活动与星形胶质细胞代谢联系起来。在本章中,我们简要回顾了大脑中表达的EAATs和葡萄糖转运体(GLUTs)的特征。此后,我们重点关注EAAT激活的作用及其与星形胶质细胞中葡萄糖利用的关联,特别探讨钠和钙离子所起的作用。接下来,我们分析了提出EAAT激活后GLUTs活性可能被调节的机制的证据(例如,激酶改变GLUTs向细胞膜的转运)。最后,我们分析了当前关于能量缺乏期间EAAT功能作为GLUT表达的可能诱导剂以防止神经元损伤的知识。