Macrophages' Functions in the Central and Peripheral Nervous Regeneration

PurposeMicroglia, the immune-competent central nervous system (CNS), have long been suspected of causing many CNS diseases. However, microglia are neuroprotective, so we must reconsider their role in CNS and peripheral nervous system (PNS) illnesses.MethodIn this review, data sources including Google Scholar, Scopus, PubMed, and Science Direct were searched for publications with no particular time restriction to get a holistic and comprehensive view of the research.ResultsRecent study shows that microglia are vital to the CNS and have complicated effects on astrocytes and myeloid cells. The pathophysiology of many disorders, including peripheral nervous system ailments, requires an understanding of microglia activities. The impact of microglia on neuronal survival in CNS and PNS diseases and bloodborne macrophages on CNS and PNS injuries is examined in this article.ConclusionMetabolic changes in glycolysis and oxidative phosphorylation are crucial in understanding the activation of microglia as they are strongly linked to reactive oxygen species formation and variations in pro- and anti-inflammatory phenotypes.Lay SummaryMacrophages play a crucial role in tissue homeostasis, inflammation, and regeneration. They are divided into pro-inflammatory (M1) and pro-repair (M2) subtypes, each with distinct functions. M2-polarized exosomes have anti-inflammatory properties and can be used to treat various diseases, including autoimmune diseases, heart, kidney, lung, liver, brain, muscle, and skin conditions.