Chronic administration of Tat-GluR23Y ameliorates cognitive dysfunction targeting CREB signaling in rats with amyloid beta neurotoxicity

• Published in: Metabolic brain disease Vol. 36; no. 4; pp. 701 - 709
• Main Authors: Ashourpour, Fatemeh, Jafari, Adele, Babaei, Parvin
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.04.2021; Springer Nature B.V
• Subjects: Alzheimer's disease; Amyloid beta-Peptides - toxicity; Animals; Biochemistry; Biomedical and Life Sciences; Biomedicine; Cell-Penetrating Peptides - administration & dosage; Cognition; Cognition & reasoning; Cognitive ability; Cognitive Dysfunction - chemically induced; Cognitive Dysfunction - drug therapy; Cognitive Dysfunction - metabolism; Cyclic AMP response element-binding protein; Cyclic AMP Response Element-Binding Protein - antagonists & inhibitors; Cyclic AMP Response Element-Binding Protein - metabolism; Drug Administration Schedule; Drug Delivery Systems - methods; Endocytosis; Glutamic acid receptors; Glutamic acid receptors (ionotropic); Hippocampus; Latency; Male; Maze Learning - drug effects; Maze Learning - physiology; Memory; Memory tasks; Metabolic Diseases; N-Methyl-D-aspartic acid receptors; Neurodegenerative diseases; Neurology; Neurosciences; Neurotoxicity; Oncology; Original Article; Peptide Fragments - toxicity; Plaques; Rats; Rats, Wistar; Receptors; Rodents; Signal transduction; Signal Transduction - drug effects; Signal Transduction - physiology; Signaling; Spatial analysis; Spatial memory; Synapses; Variance analysis; Western blotting; α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid; α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors; NMDA, cognitive function; AMPA; CREB; Alzheimer’s disease
• ISSN: 0885-7490; 1573-7365
• DOI: 10.1007/s11011-020-00662-8

Alzheimer’s disease (AD) is behaviorally characterized by memory impairments, and pathologically by amyloid β1–42 (Aβ1–42) plaques and tangles. Aβ binds to excitatory synapses and disrupts their transmission due to dysregulation of the glutamate receptors. Here we hypothesized that chronic inhibition of the endocytosis of AMPA receptors together with GluN2B subunit of NMDA receptors might improve cognition deficit induced by Aβ(1–42) neurotoxicity. Forty male Wistar rats were used in this study and divided into 5 groups: Saline + Saline, Aβ+Saline, Aβ+Ifen (Ifenprodil, 3 nmol /2 weeks), Aβ+GluR23Y (Tat-GluR23Y 3 μmol/kg/2 weeks) and Aβ+Ifen+GluR23Y (same doses and durations). Aβ(1–42) neurotoxicity was induced by intracerebroventricular (ICV) injection of Aβ1–42 (2 μg/μl/side), and then animals received the related treatments for 14 days. Cognitive performance of rats and hippocampal level of cAMP-response element-binding (CREB) were evaluated using Morris Water Maze (MWM), and western blotting respectively. Obtained data from the acquisition trials were analyzed by two way Anova and Student T test. Also one way Analysis of variance (ANOVA) with post hoc Tuckey were used to clarify between groups differences in probe test. The Group receiving Aβ, showed significant cognition deficit (long latency to platform and short total time spent in target quadrant (TTS), parallel with lower level of hippocampal CREB, versus vehicle group. While, Aβ+ GluR23Y exhibited the shortest latency to platform and the longest TTS during the probe test, parallel with the higher hippocampal level of CREB compared with other groups. The present study provides evidence that chronic administration of Tat-GluR23Y; an inhibitor of GluA2-AMPARs endocytosis, successfully restores spatial memory impaired by amyloid beta neurotoxicity targeting CREB signaling pathway.