GLP-1 signaling promotes learning and memory function, particularly in dementia and hippocampal dysfunction

Cognitive decline, particularly in dementia and other conditions presenting with hippocampal dysfunction, represents a significant unmet medical need. Current therapeutic strategies often fall short in effectively preventing or reversing memory deficits. While Glucagon-like peptide-1 (GLP-1) is primarily recognized for its roles in glucose homeostasis and food intake control, its receptor, GLP-1R, is widely expressed throughout the brain, including in the hippocampus and interconnected regions vital for learning and memory. This broad neural distribution suggests a potential neuroprotective or cognitive-enhancing role for GLP-1 beyond its metabolic functions, warranting further investigation into its therapeutic implications for memory disorders.

This comprehensive review synthesizes emerging evidence supporting a role for GLP-1 signaling in promoting learning and memory function. The authors systematically evaluated findings from preclinical rodent models, human clinical trials, and meta-analyses. They focused on studies investigating GLP-1 analog treatment effects on memory deficits and hippocampal neuronal signaling processes across various models of dementia, aging, and metabolic disruption. The review also delved into distinct neurobiological mechanisms through which GLP-1R signaling might enhance memory, aiming to provide a holistic understanding of its potential therapeutic applications.

The review highlights consistent evidence from preclinical rodent models, demonstrating that GLP-1 analog treatment improves deficits in memory function and hippocampal neuronal signaling processes. These improvements were observed across various models of dementia, aging, and metabolic disruption. Proposed neurobiological mechanisms include direct action on hippocampal GLP-1Rs following blood-brain barrier penetration, improved peripheral and central insulin sensitivity, activation of GLP-1Rs on the vagus nerve, and broader peripheral metabolic and inflammatory improvements. While human clinical trials and meta-analyses also show promise for GLP-1 analog-based treatment for memory disorders, the results thus far are mixed. > Many human studies were found to be underpowered and/or lacked comprehensive memory evaluation, suggesting a need for more robust clinical investigation. The multifaceted mechanisms underscore the complex interplay between metabolic health and cognitive function.