Neuroinflammatory effects of magnetic fields: insights into glia-mediated secondary cascades and mechanisms

Neuroinflammation is an innate immune response of the central nervous system (CNS) that typically controls infection by eliminating microbes. However, it is now understood to have a dual function, either protecting or disrupting CNS homeostasis, which is significant for neural health and disease. Magnetic fields (MFs), a widespread environmental factor, have emerged as potential triggers of neuroinflammation in the brain. Despite the growing interest in the biological effects of MFs, there is still a lack of comprehensive review synthesizing the evidence for their dual role in neuroinflammation. This review fills this gap by reframing the impact of environmental MFs on the CNS from a neuroimmunology perspective, with a particular focus on the temporal dynamics of glial activation. We evaluate the key signaling pathways through which MFs may affect neuroinflammation and glia-driven secondary events leading to abnormal neural function. Furthermore, we explore the biophysical mechanisms underlying the neuroinflammatory effects of specific MFs. By integrating scattered evidence into a coherent framework, this review provides mechanistic insights for future research and suggests new ways to evaluate the public health relevance of MF exposure.