Dexmedetomidine attenuates Alzheimer's pathogenesis by targeting the ROS-mediated XIAP-MDM2-p53 signaling axis.

Introduction: Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder with a complex pathological process, in which oxidative stress serves as a key pathogenic mechanism. Studies have shown that the anesthetic adjuvant dexmedetomidine (Dex) can improve postoperative cognitive function in AD patients. This study aimed to explore whether dexmedetomidine alleviates AD-associated neuronal apoptosis and cognitive impairment via reducing overproduction of ROS and regulating the XIAP signaling pathway. Methods: Results: Experimental results demonstrated that Aβ1-42 induced apoptosis in neuronal cells, while dexmedetomidine incubation significantly reduced Aβ1-42 elicited ROS generation, activated XIAP, suppressed MDM2 and ameliorated P53 overactivation, thereby effectively preventing neuronal death. Combined administration of NAC and dexmedetomidine reversed Aβ1-42-induced XIAP inhibition, ROS accumulation, and cell apoptosis. Furthermore, both yohimbine pre-treatment and XIAP knockdown effectively abrogated the ability of Dex to reduce ROS accumulation and mitigate apoptosis. Conclusion: This study reveals that dexmedetomidine inhibits ROS release and activates the XIAP-MDM2-p53 signaling pathway, thereby delaying apoptosis and ameliorating cognitive impairment in AD progression.