Activation of the p62/Keap1/Nrf2 Pathway Protects Against Ferroptosis in Cerebral Ischemia-Reperfusion Injury

  • J Integr Neurosci. 2026 May 26;25(5):48011. doi: 10.31083/JIN48011.
Canwen Liu  1  2 Xuanyi Dong  1 Biao Tang  1  3
Affiliations
  • 1. Key Laboratory of Vascular Biology and Translational Medicine, Hunan University of Chinese Medicine, 410208 Changsha, Hunan, China.
  • 2. Department of Hearing and Speech Sciences, School of Medicine and Health, Guangzhou Xinhua University, 510520 Guangzhou, Guangdong, China.
  • 3. Department of Neurology, People's Hospital of Ningxiang City, Hunan University of Chinese Medicine, 410600 Changsha, Hunan, China.
Abstract

Background: Protein p62 interacts with Kelch-like ECH-associated protein 1 (Keap1) competitively, triggering the oxidative stress response mediated by NF-E2-related factor 2 (Nrf2) and preventing Ferroptosis in SH-SY5Y cells. Emerging evidence implicates that this regulatory axis may confer neuroprotection against cerebral ischemia-reperfusion injury (CIRI). The current investigation was designed to elucidate whether the p62/Keap1/Nrf2 signaling pathway contributes to the amelioration of CIRI through modulation of Ferroptosis.

Methods: In SH-SY5Y cells, we used an oxygen-glucose deprivation/reperfusion (OGD/R) paradigm. In Sprague-Dawley rats, we used a middle cerebral artery occlusion/reperfusion (MCAO/R) model. Through these models, we investigated the effects of p62/Keap1/Nrf2 pathway activation. Additionally, we used in vitro experiments to analyze Ferroptosis markers, cell damage, and the expression of pathway proteins. We injected the p62-overexpressing lentivirus into SH-SY5Y cells and the lateral ventricle of rats subjected to MCAO/R. Finally, we investigated the effects of an Nrf2 activator and a Ferroptosis inhibitor.

Results: Nrf2 negatively regulated OGD/R-triggered Ferroptosis in SH-SY5Y cells by increasing Glutathione Peroxidase 4 (GPX4) expression and decreasing acyl-CoA synthetase long-chain family member 4 (ACSL4) levels. p62 overexpression in cells enhanced the interaction between Keap1 and p62, activating Nrf2 and protecting against OGD/R-triggered Ferroptosis. Activating the p62/Keap1/Nrf2 signaling pathway in vivo reduced the brain injury area, decreased neuromotor functional impairment, and decreased the expression of Ferroptosis markers in rats.

Conclusions: Activation of the p62/Keap1/Nrf2 signaling pathway reduces Ferroptosis and alleviates CIRI. This protective mechanism provides novel directions for investigating the pathological mechanisms of CIRI.

Keywords
Kelch-like ECH-associated protein 1; brain ischemia-reperfusion injury; ferroptosis; nuclear factor erythroid 2-related factor 2; oxidative stress; p62/Keap1/Nrf2 pathway; sequestosome 1.
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