# Key Components of PPEO in Antagonizing Cerebral Ischemic Reperfusion Injury in Rats by Regulating Ferroptosis Through Arachidonic Acid Metabolic Pathway

## TL;DR

This study identifies Nootkatone in Pomelo peel essential oil as a potential treatment for brain injury after stroke by targeting a specific fatty acid pathway.

## Contribution

Nootkatone is shown to antagonize ferroptosis in global cerebral ischemic reperfusion injury through the AA metabolic pathway.

## Key findings

- Nootkatone and β-pinene improved neuronal morphology and increased GPX4 levels in CIRI models.
- Nootkatone exhibited strong binding to ALOX15 and reduced lipid metabolic disturbances in the CA/CPR model.
- AA metabolism is ferroptosis-associated in global CIRI and inflammation-driven in focal CIRI.

## Abstract

Cerebral ischemic reperfusion injury (CIRI) induces irreversible neurological dysfunction with high morbidity and mortality, yet effective clinical interventions remain limited. This study focused on ferroptosis in CIRI and explored the neuroprotective components and mechanisms of Pomelo peel essential oil (PPEO)—a product derived from Guangxi’s characteristic Shatian pomelo. Sprague-Dawley rats were used to establish two CIRI models: focal CIRI via Middle Cerebral Artery Occlusion (MCAO) and global CIRI via Cardiac Arrest/Cardiopulmonary Resuscitation (CA/CPR). Analyses were conducted using metabolomics, transcriptomics, histopathological staining, biochemical assays, RT-qPCR, Western blotting (WB), and molecular docking. Metabolomic results showed altered lipid-related metabolites in both models, predominantly unsaturated fatty acids and components of the arachidonic acid (AA) metabolic pathway. Transcriptomic analysis revealed significant upregulation of PTGS1/2 in the MCAO model. Nootkatone and β-pinene improved neuronal morphology, increased glutathione peroxidase 4 (GPX4) levels, and enhanced neurological scores. Notably, Nootkatone exhibited strong binding affinity to ALOX15, and reduced lipid metabolic disturbances in the CA/CPR model. AA metabolism varies with CIRI severity: it is inflammation-driven in focal CIRI and ferroptosis-associated in global CIRI. As a key component of PPEO, Nootkatone antagonizes ferroptosis via the ACSL4-LPCAT3-ALOX15 axis, offering a novel therapeutic target for global CIRI after CA/CPR.