Rebamipide (Mucosta®), a clinically approved drug, alleviates neuroinflammation and dopaminergic neurodegeneration in a Parkinson’s disease model

Background: Parkinson’s disease (PD) is characterized by dopaminergic neuron loss, neuroinflammation, and motor dysfunction. PD is a multifactorial disease, with neuroinflammation driven by NLRP3 inflammasome activation representing an important component of its pathological progression. Therefore, we aimed to evaluate the therapeutic potential of rebamipide (Mucosta®), a clinically approved anti-inflammatory agent, in PD by targeting the NLRP3 inflammasome. Specifically, we examined the effects of rebamipide on neuroinflammation, dopaminergic neuron preservation, and motor deficits using BV2 microglia cells and a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mouse model. Main body: Rebamipide alleviated microglial activation and downstream neuroinflammation by suppressing the NLRP3–NEK7 interaction, resulting in dopaminergic neuron protection in the MPTP-induced PD model. Rebamipide downregulated IL-1β levels in BV2 microglia cells treated with α-synuclein and MPP⁺. Molecular docking analysis revealed a high binding affinity between rebamipide and the NLRP3-NEK7 interaction interface. Surface plasmon resonance analysis confirmed the direct binding of rebamipide to NLRP3, with notable kinetic affinity, supporting its role as a novel NLRP3 inflammasome inhibitor. Rebamipide significantly downregulated IL-1β levels, microglial activation, and dopaminergic neuron loss in the MPTP mouse model by disrupting inflammasome activation. Rebamipide preserved dopamine levels in the striatum and improved motor deficits, including bradykinesia and motor coordination. The neuroprotective effects of rebamipide were neutralized in NLRP3 knockout mice, confirming the dependency of its action on NLRP3. Conclusion: Considering its established clinical use, this study supports repurposing rebamipide for treating PD and other NLRP3 inflammasome-driven neuroinflammatory diseases.