P2X7 Receptor Activation Triggers a Neuroinflammatory Cascade Driving Migraine Pathophysiology: Implications for...

Migraine, a disabling neurological disorder, is increasingly recognized as being driven by neuroinflammatory processes. Purinergic receptor P2X ligand-gated ion channel 7 (P2X7R), an ATP-gated ion channel highly expressed in microglia, astrocytes, and neurons, has emerged as a pivotal regulator of these neuroimmune responses. This narrative review synthesizes the literature on P2X7R-mediated neuroinflammation and glial modulation in migraine. Evidence indicates that P2X7R activation triggers a cascade of pro-inflammatory events, including Pannexin-1 (PANX1) channel opening, NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome assembly, and the release of cytokines such as Interleukin-1β (IL-1β) and Tumor necrosis factor-α (TNF-α). Concurrently, it activates p38 MAPK and Nuclear factor kappa B (NF-κB) signaling pathways, thereby amplifying glial pro-inflammatory phenotypes and facilitating key migraine phenomena like cortical spreading depression (CSD) and trigeminovascular activation. Consistently, pharmacological or genetic inhibition of P2X7R has been shown to attenuate CSD, pain behaviors, and associated cognitive deficits in animal models of migraine. The receptor's involvement is further underscored by its link to autophagy dysfunction and central sensitization, highlighting its broad role in migraine chronification. Although these findings position P2X7R as a master regulator of neuroinflammation in migraine by integrating glial activation, cytokine release, and neuronal sensitization, most supporting evidence currently derives from animal models, a crucial point to note. This limitation, alongside heterogeneity in experimental designs, underscores the need for more translational research in humans. Nonetheless, given its central role, P2X7R inhibition emerges as a promising disease-modifying therapeutic strategy, potentially by counteracting core pathophysiological drivers of migraine.