Increased P2×2 receptors induced by amyloid-β peptide participates in the neurotoxicity in alzheimer’s disease

Amyloid beta peptide (Aβ) is tightly associated with the physiopathology of Alzheimer’s Disease (AD) as one of the most important factors in the evolution of the pathology. In this context, we previously reported that Aβ increases the expression of ionotropic purinergic receptor 2 (P2×2R). However, its role on the cellular and molecular Aβ toxicity is unknown, especially in human brain of AD patients. Using cellular and molecular approaches in hippocampal neurons, PC12 cells, and human brain samples of patients with AD, we evaluated the participation of P2×2R in the physiopathology of AD. Here, we reported that Aβ oligomers (Aβo) increased P2×2 levels in mice hippocampal neurons, and that this receptor increases at late Braak stages of AD patients. Aβo also increases the colocalization of APP with Rab5, an early endosomes marker, and decreased the nuclear/cytoplasmic ratio of Fe65 and PGC-1α immunoreactivity. The overexpression in PC12 cells of P2×2a, but not P2×2b, replicated these changes in Fe65 and PGC-1α; however, both overexpressed isoforms increased levels of Aβ. Taken together, these data suggest that P2×2 is upregulated in AD and it could be a key potentiator of the physiopathology of Aβ. Our results point to a possible participation in a toxic cycle that increases Aβ production, Ca2+ overload, and a decrease of PGC-1α. These novel findings put the P2×2R as a key novel pharmacological target to develop new therapeutic strategies to treat Alzheimer’s Disease.This work was supported by the FONDECYT [grant numbers 1161078, 1200908 (JF)], and by the Instituto de Salud Carlos III [grant numbers PI15/00665, PI19-01359] (co-financed by the Fondo Europeo de Desarrollo Regional, “Investing in your future”) (JSV). PAG is a PhD student of CONICYT [grant number 21160392].Peer reviewe