Carbamylated erythropoietin-Fc ameliorates Aβ25- 35 induced neurotoxicity by modulating autophagy, apoptosis and necroptosis in Alzheimer’s disease model rats

Introduction: Alzheimer’s disease (AD) is a progressive and chronic neurodegenerative disorder in which amyloid-β (Aβ) and hyperphosphorylated-tau (P-tau) are well-established pathological hallmarks. Carbamylated erythropoietin (CEPO-Fc) is one of the erythropoietin derivatives with neuroprotective properties against neurodegenerative disorders. However, the underlying molecular mechanism of CEPO-Fc has not been fully elucidated. Therefore, we investigated the therapeutic effects of CEPO-Fc on Aβ-induced neurotoxicity in the in-vivo rat model. Methods: Adult male Wistar rats were cannulated in the dorsal hippocampus and Aβ25-35 was microinjected for four consecutive days. CEPO-Fc was administered intranasally during the next six consecutive days. Learning and memory performance were examined (days 10-13) using the Morris water maze test. Furthermore, the hippocampal levels of critical proteins involved in apoptosis (Bax, Bcl-2 and caspase-3), necroptosis (phosphorylatedreceptor-interacting serine/threonine-protein kinase 3) and autophagy (p-Beclinbeclin-1 and phosphorylated- 1A/1B-light chain 3) were assessed using immunoblotting. Results: Behavioral analysis showed that CEPO-Fc treatment significantly improved Aβ-induced learning and memory impairment. Furthermore, the hippocampus’s molecular analysis showed that CEPO-Fc induced up-regulation of the autophagic proteins, p-Beclin-1 and p-LC3-II, while decreased caspase-3, Bax/Bcl2 ratio as well as the necroptosis factor p-RIP3. Conclusion: Our results indicate that the neuroprotective properties of CEPO-Fc in animal model of AD could be mediated by autophagy activation and inhibition of apoptosis and necroptosis processes. This study introduces CEPO-Fc as a potential protective compound against AD and other neurodegenerative disorders.