Twible Carolyn, Abdo Rober, Zhang Qi
Department of Pathology and Lab Medicine, Western University, London, ON, Canada.
Department of Anatomy and Cell Biology, Western University, London, ON, Canada.
Front Cell Neurosci. 2021 Sep 30;15:725693. doi: 10.3389/fncel.2021.725693. eCollection 2021.
Epilepsy affects approximately 50 million people worldwide, with 60% of adult epilepsies presenting an onset of focal origin. The most common focal epilepsy is temporal lobe epilepsy (TLE). The role of astrocytes in the presentation and development of TLE has been increasingly studied and discussed within the literature. The most common histopathological diagnosis of TLE is hippocampal sclerosis. Hippocampal sclerosis is characterized by neuronal cell loss within the Cornu ammonis and reactive astrogliosis. In some cases, mossy fiber sprouting may be observed. Mossy fiber sprouting has been controversial in its contribution to epileptogenesis in TLE patients, and the mechanisms surrounding the phenomenon have yet to be elucidated. Several studies have reported that mossy fiber sprouting has an almost certain co-existence with reactive astrogliosis within the hippocampus under epileptic conditions. Astrocytes are known to play an important role in the survival and axonal outgrowth of central and peripheral nervous system neurons, pointing to a potential role of astrocytes in TLE and associated cellular alterations. Herein, we review the recent developments surrounding the role of astrocytes in the pathogenic process of TLE and mossy fiber sprouting, with a focus on proposed signaling pathways and cellular mechanisms, histological observations, and clinical correlations in human patients.
癫痫在全球约影响5000万人，60%的成人癫痫发作起源于局灶性。最常见的局灶性癫痫是颞叶癫痫（TLE）。星形胶质细胞在TLE的发生和发展中的作用在文献中得到了越来越多的研究和讨论。TLE最常见的组织病理学诊断是海马硬化。海马硬化的特征是海马角神经元细胞丢失和反应性星形胶质细胞增生。在某些情况下，可观察到苔藓纤维发芽。苔藓纤维发芽在TLE患者癫痫发生中的作用一直存在争议，围绕该现象的机制尚未阐明。多项研究报告称，在癫痫状态下，苔藓纤维发芽几乎肯定与海马内的反应性星形胶质细胞增生同时存在。已知星形胶质细胞在中枢和外周神经系统神经元的存活和轴突生长中起重要作用，这表明星形胶质细胞在TLE及相关细胞改变中可能发挥作用。在此，我们综述了围绕星形胶质细胞在TLE致病过程和苔藓纤维发芽中的作用的最新进展，重点关注提出的信号通路和细胞机制、组织学观察以及人类患者的临床相关性。
