Vejar Sebastián, Oyarzún Juan E, Retamal Mauricio A, Ortiz Fernando C, Orellana Juan A
Mechanisms of Myelin Formation and Repair Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.
Departamento de Neurología, Escuela de Medicina and Centro Interdisciplinario de Neurociencias, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
Front Cell Neurosci. 2019 Jan 29;13:3. doi: 10.3389/fncel.2019.00003. eCollection 2019.
Oligodendrocytes are the myelin forming cells in the central nervous system (CNS). In addition to this main physiological function, these cells play key roles by providing energy substrates to neurons as well as information required to sustain proper synaptic transmission and plasticity at the CNS. The latter requires a fine coordinated intercellular communication with neurons and other glial cell types, including astrocytes. In mammals, tissue synchronization is mainly mediated by connexins and pannexins, two protein families that underpin the communication among neighboring cells through the formation of different plasma membrane channels. At one end, gap junction channels (GJCs; which are exclusively formed by connexins in vertebrates) connect the cytoplasm of contacting cells allowing electrical and metabolic coupling. At the other end, hemichannels and pannexons (which are formed by connexins and pannexins, respectively) communicate the intra- and extracellular compartments, serving as diffusion pathways of ions and small molecules. Here, we briefly review the current knowledge about the expression and function of hemichannels, pannexons and GJCs in oligodendrocytes, as well as the evidence regarding the possible role of these channels in metabolic and synaptic functions at the CNS. In particular, we focus on oligodendrocyte-astrocyte coupling during axon metabolic support and its implications in brain health and disease.
少突胶质细胞是中枢神经系统（CNS）中形成髓鞘的细胞。除了这一主要生理功能外，这些细胞还通过为神经元提供能量底物以及维持CNS中适当的突触传递和可塑性所需的信息来发挥关键作用。后者需要与神经元和其他胶质细胞类型（包括星形胶质细胞）进行精细协调的细胞间通讯。在哺乳动物中，组织同步主要由连接蛋白和泛连接蛋白介导，这两个蛋白家族通过形成不同的质膜通道来支持相邻细胞之间的通讯。一方面，间隙连接通道（GJC；在脊椎动物中仅由连接蛋白形成）连接接触细胞的细胞质，实现电耦合和代谢耦合。另一方面，半通道和泛通道（分别由连接蛋白和泛连接蛋白形成）连通细胞内和细胞外区室，作为离子和小分子的扩散途径。在这里，我们简要回顾一下目前关于少突胶质细胞中半通道、泛通道和GJC的表达和功能的知识，以及这些通道在CNS代谢和突触功能中可能作用的证据。特别是，我们关注轴突代谢支持过程中的少突胶质细胞-星形胶质细胞耦合及其对脑健康和疾病的影响。
