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Vit, J.-P.

Publications and source records attributed to Vit, J.-P..

2 recordsLinked to original sources

Epigenetic derepression of H3K9me3 mitigates Alzheimer-related pathology and improves cognition via immunomodulation and Vgf induction

We investigated the role of histone 3 lysine 9 trimethylation (H3K9me3), an epigenetic mechanism involved in the repression of synaptic plasticity and memory-related genes, within aging and Alzheimers disease (AD). Our study reveals that elevated cortical H3K9me3 strongly correlates with cognitive dysfunction in individuals with mild cognitive impairment (MCI) and AD. In old (18 months) and younger (14 months) APPSWE/PS1{Delta}E9 and 3xTg AD mouse models, inhibiting SUV39H1 methyltransferase with ETP69, substantially reduces cerebral H3K9me3 levels and attenuates amyloid-{beta} burden, tau pathology, and gliosis. Administration of ETP69 further promotes dendritic spine formation, leading to rapid and sustained improvements in cognitive function. Proteomics analysis indicates that a significant proportion of dysregulated proteins in the brains of AD-model mice are reversed by ETP69. These proteins are enriched for synaptic plasticity and learning-related pathways. ETP69 exerts its effects through multiple neuroprotective mechanisms, including regulation of neuroinflammation, induction of both blood and cerebral-infiltrating monocytes involved in cerebral A{beta} clearance. Moreover, ETP69 activates brain-derived neurotrophic factor (Bdnf) network, and particularly its downstream effector neurosecretory protein Vgf. These findings support the pharmacological inhibition of H3K9me3-mediated gene silencing to reverse AD-related pathology and cognitive decline.

neuroscience↗

AAV9-MCT8 delivery at juvenile stage ameliorates neurological and behavioral deficits in an AHDS mouse model

Allan-Herndon-Dudley syndrome (AHDS) is a severe X-linked intellectual and psychomotor disability disorder accompanied by abnormal thyroid hormone (TH) levels. AHDS is caused by inactivating mutations in the monocarboxylate transporter 8 (MCT8), a specific TH transporter widely expressed in the central nervous system. MCT8 gene mutations cause impaired transport of TH across brain barriers, leading to insufficient neural TH supply. There is currently no successful therapy for the neurological symptoms. AAV9-based gene therapy is a promising approach to treat monogenic neurological disorders. Here, the potential of this approach was tested in the well-established double knockout (dKO) Mct8-/y;Oatp1c1-/- mouse model of AHDS, which displays disease-relevant neurological and TH phenotypes. Systemic intravenous delivery of AAV9-MCT8 at a juvenile stage led to improved locomotor and cognitive function, as well as rescue of T3-brain content and T3-related gene expression. This preclinical study indicates that this gene therapy may improve the neurological symptoms of AHDS patients.

neuroscience↗