Multimodal MR Imaging Reveals the Mechanisms of Post-Cardiac-Arrest Brain edema: Ferroptosis-Mediated BBB Disruption

Yunke Tan1, HaoYi Ye2, Qiulin Ge1

  • 1Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.

Abstract

Insights

Cardiac arrest (CA) triggers iron overload and ferroptosis, leading to blood-brain barrier (BBB) disruption and brain edema. Multimodal MRI noninvasively detects this ferroptosis-related brain injury after CA and return of spontaneous circulation (ROSC).

Area of Science:

  • Neuroscience
  • Biochemistry
  • Radiology

Background:

  • The precise role of ferroptosis in cerebral edema following cardiac arrest (CA) is not well understood.
  • Investigating ferroptosis is crucial for understanding brain injury mechanisms after CA.

Purpose of the Study:

  • To determine if ferroptosis contributes to blood-brain barrier (BBB) disruption after CA.
  • To assess the impact of ferroptosis on aquaporin-4 (AQP4) function post-CA.
  • To explore the potential of multiparametric MRI in detecting ferroptosis-related brain injury.

Main Methods:

  • A prospective study using an asphyxia-induced CA rat model.
  • Multiparametric MRI (T2-weighted, QSM, IVIM, 1H-MRS) was performed 24 hours post-ROSC.
  • Histology, immunohistochemistry, Western blot, and electron microscopy validated MRI findings.

Main Results:

  • CA induced neurological deficits and hippocampal iron accumulation, confirmed by QSM.
  • Elevated oxidative stress and ferroptosis markers (GPX4, ACSL4) were observed.
  • Ferroptosis led to BBB leakage, AQP4 depolarization, cytotoxic edema (IVIM D reduction), and neuronal damage (1H-MRS findings).

Conclusions:

  • A sequential cascade of iron overload, ferroptosis, BBB disruption, and edema occurs after CA and ROSC.
  • Multimodal MRI can noninvasively detect and monitor ferroptosis-related brain injury.
  • This approach offers a potential platform for evaluating neuroprotective interventions.