The plasticity of plasticity: lesson from remote microglia induced by focal central nervous system injury

Maria Teresa Viscomi

doi:10.4103/1673-5374.264448

摘要：The last decades have represented an important season in the re-con-ceptualization of brain plasticity, especially in extending the concept at events occurring beyond the developmental stage and in demonstrat-ing the profound impact of these changes on so-called spontaneous recovery after central nervous system (CNS) injuries. The study of the cellular, molecular, functional and structural mechanisms involved in brain plasticity has clearly emphasized the multitude of players engaged in this phenomenon, leading to the conceptualization that non-neuronal cells and non-neuronal mechanisms intervene in these changes and orchestrate some of the responses observed (Werner and Stevens, 2015). Among the different non-neuronal cells and non-neu-ronal substrates of injury-induced plasticity is becoming increasingly recognized that microglia drive a series of intrinsic CNS responses after damage (Sandvig et al., 2018; Bisicchia et al., 2019). Interestingly, the modulatory influence of microglia on brain after injury constitutes a subset of the broader brain plasticity phenomena, defined "plasticity of plasticity" (Banati, 2002). The term well describes the great capacity of microglia in modifying their morphology and their transcriptional identity in response to environment alteration/injury. The responses of microglia, like the other CNS cells, are not linear, compartmentalized, or binary, but are multifaceted, finely tuned by the extrinsic and intrin-sic factors such as the nature of the stimulus, the extracellular environ-ment and the molecular repertoire that is involved in the response and the prior state of the cells (Lynch, 2009).