Konishi Hiroyuki, Kiyama Hiroshi, Ueno Masaki
Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, 466-8550, Japan.
Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata University, Niigata, 951-8585, Japan.
Int J Dev Neurosci. 2019 Oct;77:18-25. doi: 10.1016/j.ijdevneu.2018.09.009. Epub 2018 Oct 4.
Microglia colonize the central nervous system (CNS) parenchyma during embryogenesis and contribute to various developmental processes leading to the formation of refined neural circuits. In this review, we focus on the bidirectional function of microglia during normal CNS development and discuss recent perspectives on the functions of microglia in neural circuit formation. Microglia participate in neurogenesis, migration, axonal growth, and synapse formation and remodeling, all of which are fundamental for the establishment of neural networks, by secreting a variety of molecules toward neurons and phagocytosing both live and dying neurons or their debris. Intriguingly, microglia play dual roles in each of the neurodevelopmental processes that they affect. For instance, microglia modulate synapse numbers by both promoting the formation of new synapses and eliminating unnecessary synapses. The study of the developmental roles of microglia is essential not only for understanding normal CNS development but also for preventing developmental brain disorders caused by microglial dysfunction.
小胶质细胞在胚胎发育过程中定殖于中枢神经系统（CNS）实质，并参与导致精细神经回路形成的各种发育过程。在本综述中，我们聚焦于小胶质细胞在正常CNS发育过程中的双向功能，并讨论小胶质细胞在神经回路形成中的功能的最新观点。小胶质细胞通过向神经元分泌多种分子并吞噬存活和死亡的神经元或其碎片，参与神经发生、迁移、轴突生长以及突触形成和重塑，所有这些对于神经网络的建立都是至关重要的。有趣的是，小胶质细胞在它们所影响的每个神经发育过程中都发挥着双重作用。例如，小胶质细胞通过促进新突触的形成和消除不必要的突触来调节突触数量。研究小胶质细胞的发育作用不仅对于理解正常的CNS发育至关重要，而且对于预防由小胶质细胞功能障碍引起的发育性脑部疾病也至关重要。
