Purα overexpression mitigates neonatal hypoxic-ischemic brain damage by inhibiting neuronal pyroptosis via the P2X7R/NLRP3/Caspase-1 pathway

Hypoxic-ischemic brain damage (HIBD) is a common neonatal disorder that often leads to permanent neurological sequelae. Neuronal pyroptosis, a pro-inflammatory form of programmed cell death, has been increasingly recognized as a key contributor to neuronal damage and subsequent neurological deficits in HIBD. However, effective therapeutic strategies for HIBD remain limited, highlighting the urgent need to identify novel therapeutic targets. Purine-rich element-binding protein α (Purα) is a multifunctional DNA/RNA-binding protein involved in gene transcription and nervous system regulation. However, its role in neonatal HIBD has not been defined. Here, we investigated the neuroprotective effects of Purα in both in vivo and in vitro models of HIBD. We found that endogenous Purα protein levels were markedly reduced in brain tissue from HI-challenged neonatal mice and in primary cortical neurons subjected to oxygen-glucose deprivation/reoxygenation (OGD/R). Purα overexpression effectively reduced cerebral infarction, alleviated neuronal injury, attenuated brain atrophy, and improved neurological outcomes in neonatal HIBD mice. In cultured neurons, Purα overexpression significantly increased cell viability and reduced cell death following OGD/R. RNA sequencing identified purinergic 2X7 receptor (P2X7R) as a potential downstream target of Purα, consistent with P2X7R's established role in pyroptosis regulation. Mechanistic studies further demonstrated that Purα overexpression suppressed P2X7R expression and inhibited activation of the NLRP3/Caspase-1 pathway, as indicated by reduced levels of P2X7R, NLRP3, Caspase-1, cleaved Caspase-1, GSDMD-N, and IL-1β. Collectively, these findings reveal a novel role for Purα in mitigating neuronal pyroptosis via regulation of the P2X7R/NLRP3/Caspase-1 pathway and support Purα as a promising therapeutic target for neonatal HIBD.