Perampanel Regulates Neuroinflammation and Ferroptosis via Activating FSP1 Following Brain Ischemia

Ischemic stroke remains a leading cause of global disability and mortality, with neuroinflammation and ferroptosis emerging as critical contributors to secondary neuronal damage. Perampanel, a non-competitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist, exhibits neuroprotective properties in neurological disorders, yet its mechanisms in ischemic stroke remain incompletely understood. This study investigated the therapeutic potential of post-injury perampanel administration in both in vivo and in vitro models, focusing on neuroinflammation, ferroptosis, and the role of ferroptosis suppressor protein 1 (FSP1).

Rats received intraperitoneal perampanel (1.5 mg/kg) 10-15 minutes post-reperfusion for 3 days and exposed to middle cerebral artery occlusion (MCAO) for 60 minutes. Neurological function, neuronal survival, and markers of neuroinflammation and ferroptosis were assessed via immunostaining, Western blot, and behavioral tests. The in vitro ischemia model was mimicked by oxygen glucose deprivation (OGD) in primary cultured cortical neurons.

Perampanel significantly attenuated MCAO-induced neuronal loss (NeuN⁺ cells) and improved motor coordination in rotating pole tests. It suppressed microglial (Iba-1⁺) and astrocytic (GFAP⁺) activation, indicating its anti-inflammatory effects. Mechanistically, perampanel reversed the MCAO-driven downregulation of ferroptosis markers FTH-1 and GPX-4, while enhancing neuronal FSP1 expression. Crucially, the FSP1 inhibitor icFSP1 abolished perampanel-mediated neuroprotection, neuronal preservation, and ferroptosis suppression, supporting the FSP1-dependent mechanisms. In in vitro conditions, perampanel exerted protective effects in a dose- and time-dependent manner. The results of immunostaining and Western blot showed that perampanel attenuated neuronal ferroptosis via activation of FSP1.

These findings demonstrate that perampanel mitigates post-ischemic brain injury by inhibiting neuroinflammation and neuronal ferroptosis via FSP1 activation. This study highlights FSP1 as a novel therapeutic target and positions perampanel as a promising candidate for ischemic stroke treatment, leveraging its established safety profile and clinical availability.