IMRCs Alleviate Post-resuscitation Cerebral Injury Possibly by Inhibiting Ferroptosis in a Porcine Model of Cardiac Arrest.

Cerebral injury following cardiac arrest (CA) is a primary contributor to patients' mortality and poor neurological outcome. However, there are currently no definitive and effective therapeutic approaches. Emerging evidence has indicated that mesenchymal stem cell (MSC) pretreatment exerted protective effects against cardiac and cerebral injuries in the porcine model of CA. However, given the unpredictable nature of CA, we administered immunity-and-matrix-regulatory cells (IMRCs) derived from human embryonic stem cells (hESCs) following CA to investigate whether IMRCs could alleviate cerebral injury following CA in swine. In vivo, a porcine CA model was established using male domestic white swine. In vitro, CA-induced injury was simulated by subjecting HT22 cells and primary cultures of hippocampal neurons to hypoxia/reoxygenation (H/R). SAT1 overexpression was achieved in HT22 cells via lentiviral transduction and in primary cultures of hippocampal neurons via adeno‑associated virus (AAV) transduction. Following IMRC administration, neurological function, cerebral injury, cell viability, lactate dehydrogenase (LDH) release, and ferroptosis-related indicators were systematically evaluated using a series of experimental assays. IMRC administration significantly decreased ferroptosis-related ferrous iron (Fe2+), lipid reactive oxygen species (ROS), malondialdehyde (MDA), and 4‑hydroxynonenal (4‑HNE) at 24, 48, and 72 h following CA, while concomitantly elevating glutathione (GSH) levels and mitigating cerebral injury. Further in vitro studies demonstrated that SAT1 overexpression promoted ALOX15 activation and suppressed GPX4 expression, thereby exacerbating H/R-induced neuronal ferroptosis. Moreover, SAT1 overexpression was found to partially attenuate the protective effects of IMRCs against H/R-induced ferroptosis. In vivo, IMRC administration downregulated the expression of SAT1 and ALOX15, while concurrently upregulating GPX4 levels. Early post-resuscitation administration of IMRCs attenuated cerebral injury following cardiac arrest, and this protective effect was possibly related to the suppression of ferroptosis via regulation of the SAT1/ALOX15/GPX4 signaling pathway.