Inhibition of neuronal ferroptosis protects hemorrhagic brain

TLDR

Intracerebral hemorrhage causes high mortality and morbidity, yet the mechanisms of post‑ICH neuronal death remain poorly understood. The study aims to elucidate the role of ferroptosis in post‑ICH neuronal death to inform future preclinical strategies. The authors show that ferroptosis occurs after ICH and that the ferroptosis inhibitor ferrostatin‑1 protects neurons, reduces iron deposition, lipid ROS, and COX‑2 expression, improves neurological outcomes, and that COX‑2 may serve as a ferroptosis biomarker.

Abstract

Intracerebral hemorrhage (ICH) causes high mortality and morbidity, but our knowledge of post-ICH neuronal death and related mechanisms is limited. In this study, we first demonstrated that ferroptosis, a newly identified form of cell death, occurs in the collagenase-induced ICH model in mice. We found that administration of ferrostatin-1, a specific inhibitor of ferroptosis, prevented neuronal death and reduced iron deposition induced by hemoglobin in organotypic hippocampal slice cultures (OHSCs). Mice treated with ferrostatin-1 after ICH exhibited marked brain protection and improved neurologic function. Additionally, we found that ferrostatin-1 reduced lipid reactive oxygen species production and attenuated the increased expression level of PTGS2 and its gene product cyclooxygenase-2 ex vivo and in vivo. Moreover, ferrostatin-1 in combination with other inhibitors that target different forms of cell death prevented hemoglobin-induced cell death in OHSCs and human induced pluripotent stem cell–derived neurons better than any inhibitor alone. These results indicate that ferroptosis contributes to neuronal death after ICH, that administration of ferrostatin-1 protects hemorrhagic brain, and that cyclooxygenase-2 could be a biomarker of ferroptosis. The insights gained from this study will advance our knowledge of the post-ICH cell death cascade and be essential for future preclinical studies.