Oxytocin regulated pyroptosis through OTR/Mitochondria mediated pathway toimprove hypoxia-induced brain injury

Background: Hypoxic-ischemic encephalopathy (HIE) is a major cause of neonatal mortality and neurological dysfunction, with limited therapeutic options. Mitochondrial fusion and fission dynamics are implicated in neuronal injury and development. This study sought to evaluate the therapeutic potential of OT, a nonapeptide hormone synthesized in the hypothalamus, in hypoxic brain injury and explore its underlying molecular mechanisms, focusing on its role in modulating mitochondrial dynamics and neuroinflammation. Methods: Wild-type C57BL/6 neonatal mice were randomly divided into four groups: Sham, Hypoxia, Hypoxia + OT groups, and Hypoxia + OT + Cligosiban groups. The hypoxic brain injury model was established by exposure five-day-old mice to hypoxia (10% oxygen) for 7 days, while the Sham group was maintained under normoxic conditions (21% oxygen). OT (0.1mg/kg) was intraperitoneally administered every other day in the treatment group. Neuronal brain damage was assessed using immunofluorescence, HE, and Nissl staining. Mitochondrial fission and fusion dynamics were evaluated through the expression of Mitofusin 1(Mfn1), Optic Atrophy 1(OPA1), and Dynamin-related protein 1(Drp1). Western blot analysis was performed to evaluate the OT receptor (OTR) and NLRP3 inflammasome mediated pyroptosis. Result: Immunofluorescence, HE, and Nissl staining revealed pathological neuronal reduction in hypoxia condition, which was alleviated by OT. Hypoxic significantly decreased Mfn1 and OPA1 expression while increasing Drp1 expression, which were reversed by OT. Moreover, cleaved-caspase1, Gsdmd, and IL-1β expression was significantly elevated in hypoxia condition, and OT could downregulate these proteins expression. OTR expression was significantly increased in hypoxia condition. The use of Cligosiban, OTR antagonist, elevated Drp1 expression compared to the OT group. Mechanically, OT binds to OTR to alleviate mitochondrial dysfunction and attenuate NLRP3-mediated inflammation and GSDMD-mediated pyroptosis, exerting a protective role in hypoxia-induced brain injury. Conclusion: Our findings revealed that OT protects against hypoxic neonatal brain injury by maintaining mitochondrial homeostasis, suppressing neuroinflammation, and preventing pyroptosis through OTR-mediated signaling. These results showed OT as a promising therapeutic candidate for hypoxic brain injury, offering a mechanistic foundation for its clinical application. This work was supported by grant from the Shandong Provincial Natural Science Foundation (No. ZR2022MH052). This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.