GLP-1R agonist semaglutide protects human forebrain organoids from cholesterol-induced neurotoxicity.

INTRODUCTION

Dysregulated cholesterol metabolism represents a critical metabolic stressor in the central nervous system, contributing to neuronal injury across multiple neurological conditions, including Alzheimer's disease (AD). While glucagon-like peptide-1 receptor (GLP-1R) agonists show neuroprotective potential, their capacity to directly mitigate cholesterol-induced metabolic stress in human neural cells remains to be established.

METHODS

Here, we modeled metabolic stress using human induced pluripotent stem cell-derived forebrain organoids exposed to cholesterol overload. The protective effects of the GLP-1R agonist semaglutide were characterized by integrating bulk/single-cell transcriptomics, calcium imaging, and biochemical assays. Furthermore, clinical translatability was supported by mapping organoid expression signatures against human post mortem neurodegenerative brain datasets.

RESULTS

Cholesterol overload induced cellular stress and transcriptomic alterations that partially overlapped with AD-associated signatures. Semaglutide protected neural cells from lipotoxic injury. Intracellularly, GLP-1R activation engaged the cyclic adenosine 3',5'-monophosphate-protein kinase A and phosphoinositide 3 kinase-protein kinase B-mechanistic target of rapamycin signaling pathways, consistent with reduced lipid droplet accumulation and oxidative stress. Intercellularly, single-cell analysis indicated partial preservation of disrupted cellular communication, including the neurotrophic midkine signaling network. Functionally, semaglutide stabilized cellular calcium activity patterns under metabolic stress.

DISCUSSION: These findings highlight the role of cholesterol homeostasis in maintaining neuronal integrity and position GLP-1R signaling as a candidate protective axis under metabolic stress, offering insights into therapeutic strategies for AD and broader neurodegenerative disorders.