Lynx1 Prevents Long-Term Potentiation Blockade and Reduction of Neuromodulator Expression Caused by Aβ1-42 and JNK Activation

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels. Many neurodegenerative diseases are accompanied by cognitive impairment associated with the dysfunction of nAChRs. The human membrane-tethered prototoxin Lynx1 modulates nAChR function in the brain areas responsible for learning and memory. In this study, we have demonstrated for the first time that the β-amyloid peptide Aβ(1-42) decreases Lynx1 mRNA expression in rat primary cortical neurons, and that this decrease is associated with the activation of c-Jun N-terminal kinase (JNK). In addition, we have demonstrated that the Lynx1 expression decrease, as well as the blockade of the long-term potentiation underlying learning and memory, caused by Aβ(1-42), may be prevented by incubation with a water-soluble Lynx1 analogue. Our findings suggest that the water-soluble Lynx1 analogue may be a promising agent for the improvement of cognitive deficits in neurodegenerative diseases.