Department of Neuroscience Rita Levi-Montalcini, Neuroscience Institute Cavalieri Ottolenghi, University of Turin Turin, Italy.
Front Neurosci. 2014 May 23;8:122. doi: 10.3389/fnins.2014.00122. eCollection 2014.
NG2-expressing parenchymal precursors (NG2+p) serve as primary source of myelinating oligodendrocytes in both the developing and adult Central Nervous System (CNS). However, their abundance, limited differentiation potential at adult stages along with stereotypic reaction to injury independent of the extent of myelin loss suggest that NG2+p exert functions additional to myelin production. In support of this view, NG2+p express a complex battery of molecules known to exert neuromodulatory and neuroprotective functions. Further, they establish intimate physical associations with the other CNS cell types, receive functional synaptic contacts and possess ion channels apt to constantly sense the electrical activity of surrounding neurons. These latter features could endow NG2+p with the capability to affect neuronal functions with potential homeostatic outcomes. Here we summarize and discuss current evidence favoring the view that NG2+p can participate in circuit formation, modulate neuronal activity and survival in the healthy and injured CNS, and propose perspectives for studies that may complete our understanding of NG2+p roles in physiology and pathology.
表达 NG2 的实质前体细胞（NG2+ p）是中枢神经系统（CNS）在发育和成年阶段形成髓鞘少突胶质细胞的主要来源。然而，它们的丰富程度、成年阶段有限的分化潜能以及与髓鞘丢失程度无关的定型反应表明，NG2+ p 发挥的功能不仅仅是产生髓鞘。支持这一观点的是，NG2+ p 表达了一系列已知具有神经调节和神经保护功能的复杂分子。此外，它们与其他中枢神经系统细胞类型建立了密切的物理联系，接收功能性突触接触，并具有离子通道，能够随时感知周围神经元的电活动。这些后者的特征可能使 NG2+ p 具有影响神经元功能的能力，并可能产生稳态结果。在这里，我们总结并讨论了目前支持 NG2+ p 能够参与回路形成、调节中枢神经系统健康和损伤时神经元活性和存活的观点，并提出了一些观点，这些观点可能有助于我们全面理解 NG2+ p 在生理学和病理学中的作用。
