INTRODUCTION: Epilepsy is characterized by recurrent seizure activity, often driven by oxidative stress and neuroinflammation, which together accelerate disease progression and contribute to pharmacoresistance. ~30% of epileptic patients are resistant to available antiseizure medications, which primarily target symptoms and fail to address the underlying mechanisms of epileptogenesis. This therapeutic gap underscores the need for interventions that not only suppress seizures but also prevent epilepsy development and modify its progression.

AIM(S): To develop an activity-dependent gene therapy that selectively activates and targets oxidative stress in hyperactive neurons using cfos-driven expression of Nrf2, a master regulator of antioxidant defense, while preserving redox balance in healthy tissue.

METHOD(S): An AAV9 vector encoding cfos-Nrf2 was stereotaxically injected into the hippocampus of rats. Status epilepticus was induced to model epilepsy, and cfos-Nrf2 expression were assessed for temporal kinetics and neuronal specificity. Activation of the Nrf2 pathway was confirmed via upregulation of antioxidant targets. Sequential PTZ-induced challenges evaluated transient neuroprotection. Long-term video-ECoG monitoring via implanted transmitters assessed seizure suppression. Behavioral tests were performed to evaluate cognitive and anxiety-related outcomes.

RESULTS: The cfos driven expression was rapidly induced post-SE, peaked between 12-24 hrs, and was restricted to neurons. Nrf2 activation was confirmed by NQO1 upregulation. Repeated PTZ paradigm confirmed a transient yet effective neuroprotection. Long-term monitoring revealed sustained seizure suppression and reduced interictal activity. cfos-Nrf2-treated animals also showed improved spatial memory and reduced anxiety.

CONCLUSIONS: The cfos-Nrf2 system offers a self-regulating, seizure-responsive gene therapy with long-lasting efficacy. It enables temporally restricted targeted neuroprotection that reduces tolerance risk, and addresses comorbidities in epilepsy.

FINANCIAL SUPPORT: NA