Plain Language Summary
Comprehensive review synthesizing recent evidence on semaglutide's potential to target neuroinflammation as a primary driver of neurodegenerative disease progression across Alzheimer's, Parkinson's, multiple sclerosis, ALS, FTD, Huntington's, and Lewy body dementia. Reviews mechanisms by which GLP-1R agonism reduces microglial activation, cytokine release, and neuronal oxidative stress. Provides a unified neuroinflammatory framework for semaglutide's potential therapeutic scope across multiple neurodegenerative conditions—motivating disease-specific clinical trials following the inconclusive Alzheimer's evoke/evoke+ results.
Abstract
BACKGROUND: Chronic neuroinflammation is increasingly recognized not as a secondary effect but as a primary driver of neurodegenerative disease progression. In conditions such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), Huntington's disease (HD), and Lewy body dementia (LBD), dysregulated glial activity, marked by sustained microglial and astrocytic activation, initiates a cascade of cytokine release, oxidative stress, and impaired neuronal support. This review synthesizes recent advances in understanding these shared inflammatory processes, emphasizing how glia-centric pathology shapes disease-specific trajectories and therapeutic responses.
FINDINGS: Within this framework, we evaluate the therapeutic potential of semaglutide, a glucagon-like peptide-1 receptor agonist (GLP-1RA) with emerging neuroprotective properties. Preclinical studies suggest that semaglutide can suppress pro-inflammatory signaling, mitigate oxidative injury, and enhance key anti-inflammatory and neuroprotective pathways that restore trophic support and cellular resilience. We also examine real-world evidence and emerging human clinical trial data, which recently demonstrated that semaglutide rapidly modulates AD pathology by significantly reducing cerebrospinal fluid (CSF) levels of p-tau, t-tau, and neurogranin, and promoting a less inflammatory CD8T-cell signature. In addition to reduction in neuroinflammation marker, YKL-40. While subsequent large-scale Phase 3 trials in early AD did not meet primary cognitive endpoints (CDR-SB) despite favorable biomarker modulation.
CONCLUSION: Positioning semaglutide as a therapeutic option targeting neuroinflammation-mediated neuropathology, this review underscores its potential for repurposing as a disease-modifying therapy across diverse neurodegenerative disorders and highlights the urgent need for targeted trials in MS, ALS, FTD, HD, and LBD-conditions that remain without effective immunomodulatory treatments despite clear inflammatory origins. However, while direct CSF measurements confirm limited but measurable BBB penetration, the clinical translation of its effects remains a key challenge.