Oligodendroglia-lineage cells in brain plasticity, homeostasis and psychiatric disorders

Abstract

Adult oligodendrocyte progenitor cells are uniformly distributed in both gray and white matter, displaying robust proliferative and migratory potential during health and disease. Recently, developments in new experimental approaches have brought about several novel insights about NG2-glia and myelinating oligodendrocytes, indicating a diverse toolkit of functions in experience-dependent myelination and homeostasis in the adult CNS. In this review, we summarize some of the topical studies that highlight newly emerging findings implicating oligodendroglia-lineage cells in brain plasticity, homeostasis and pathophysiology of neuropsychiatric disorders.

Figure 1. NG2-glia in the CNS

(A) NG2-glia proliferate and differentiate into mature OLs in grey and white matter [36,63,125]. (B) NG2-glia survey their local environment and assist in glial scar formation [37,38]. (C) NG2-glia have cell-cell bidirectional interaction with neurons. They receive excitatory and inhibitory synaptic transmission from neurons [39,40,42,45,51,127,128]. Conversely, they influence synaptic activity in neurons by releasing neuromodulatory factors [57,70]. (D) NG2-glia support and regulate blood brain barrier function [–132]. (E) NG2-glia coordinate and promote angiogenesis through autocrine activation of canonical Wnt7a/7b signaling [129]. (F) NG2-glia are required for median eminence-mediated leptin sensing and body weight control [75]. (G) NG2-glia mediate behavioral responses in stress and sensorimotor gating, possibly through secreted factors [70,76,99] (H) NG2-glia regulate microglia through the hepatocyte growth factor (HGF) for the maintenance of neuronal function and survival [74].

Figure 2. Behavioral outcomes after NG2-glial perturbation in the CNS

See text for details. Figure refers to [69,70,74,75,78,79,99,111]. Red indicates experimental interventions. Dashed lines indicate possible interactions. Lines with circular arrowheads indicate rescue/recovery experiments.