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Guns, J.

Publications and source records attributed to Guns, J..

2 recordsLinked to original sources

The ApoC2 mimetic peptide D6PV enhances remyelination by stimulating oxidative phosphorylation in oligodendrocytes

Failure of remyelination drives neurodegeneration in demyelinating disorders such as multiple sclerosis (MS), with disrupted lipid handling and metabolic stress in oligodendrocyte precursor cells (OPCs) posing major barriers to repair. Here, we identify the dual ApoC-II mimetic-ApoC-III antagonist peptide D6PV as a metabolic modulator that directly enhances OPC differentiation and myelin repair. Across ex vivo and in vivo models of chemically induced demyelination, D6PV promotes oligodendrocyte maturation and restores myelin integrity independently of lipoprotein hydrolysis or modulation of lipid droplet-containing phagocytes. Guided by transcriptomics analyses, we find that D6PV stimulates mitochondrial oxidative phosphorylation and fatty acid {beta}-oxidation, while suppressing inflammatory transcriptional programs, thereby driving OPCs toward a myelinating phenotype. Notably, D6PV does not alter peripheral immune composition or autoimmune-driven pathology in the experimental autoimmune encephalomyelitis model, indicating a central nervous system (CNS) cell-autonomous effect. These findings reveal a metabolism-linked pathway for remyelination and position D6PV as a promising therapeutic strategy to enhance CNS repair in demyelinating diseases.

neuroscience↗

Extracellular vesicle-associated cholesterol dictates the regenerative functions of macrophages in the brain

Macrophages play major roles in the pathophysiology of various neurological disorders, being involved in seemingly opposing processes such as lesion progression and resolution. Yet, the molecular mechanisms that drive their harmful and benign effector functions remain poorly understood. Here, we demonstrate that extracellular vesicles (EVs) secreted by repair-associated macrophages (RAMs) enhance remyelination ex vivo and in vivo by promoting the differentiation of oligodendrocyte precursor cells (OPCs). Guided by lipidomic analysis and applying cholesterol depletion and enrichment strategies, we find that EVs released by RAMs show markedly elevated cholesterol levels and that cholestserol abundance controls their reparative impact on OPC maturation and remyelination. Mechanistically, EV-associated cholesterol was found to promote OPC differentiation through direct membrane fusion. Collectively, our findings highlight that EVs are essential for cholesterol trafficking in the brain and that changes in cholesterol abundance dictate the reparative impact of EVs released by macrophages in the brain, potentially having broad implications for therapeutic strategies aimed at promoting repair in neurodegenerative disorders.

neuroscience↗