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Tissot, C.

Publications and source records attributed to Tissot, C..

3 recordsLinked to original sources

Cryo-EM structure of Alzheimer disease tau filaments with PET ligand MK-6240

Positron Emission Tomography (PET) ligands have advanced Alzheimers disease (AD) diagnosis and treatment. Using autoradiography and cryo-EM, we identified AD brain tissue with elevated tau burden, purified filaments, and determined the structure of second-generation high avidity PET ligand MK-6240 at 2.31 [A] resolution, which bound at a 1:1 ratio within the cleft of tau paired-helical filament (PHF), engaging with glutamine 351, lysine K353, and isoleucine 360. This information elucidates the basis of MK-6240 PET in quantifying PHF deposits in AD and may facilitate the structure-based design of superior ligands against tau amyloids.

neuroscience↗

Transcriptomic signatures of Abeta- and tau-induced neuronal dysfunction reveal inflammatory processes at the core of Alzheimer's disease pathophysiology

Molecular mechanisms enabling pathology-induced neuronal dysfunction in Alzheimers disease (AD) remain elusive. Here, we use mechanistic computational models to infer the combined influence of PET-measured A{beta} and tau burdens on fMRI-derived neuronal activity and to subsequently identify the transcriptomic spatial correlates of AD pathophysiology. Our results reveal overrepresented genes and biological processes that participate in synaptic degeneration and interact with A{beta} and tau deposits. Furthermore, we confirmed the central role of the immune system and neuroinflammatory pathways within AD pathogenesis; microglia were significantly enriched in the gene set associated with A{beta} and tau synergistic influences on neuronal activity. Lastly, our computational approach unveiled drug candidates with the potential to halt or reduce the observed pathological effects on neuronal activity, including existing medication for cancer, immune disorders, and cardiovascular diseases, many currently under clinical evaluation in AD. Overall, these findings support the notion that the AD brain experiences functional changes intricately associated with a diverse spectrum of molecular processes.

neuroscience↗

Urolithin A induces cardioprotection and enhanced mitochondrial quality during natural aging and heart failure

Cardiovascular diseases remain the primary cause of global mortality, necessitating effective strategies to alleviate their burden. Mitochondrial dysfunction is a driving force behind aging and chronic conditions, including heart disease. Here, we investigate the potential of Urolithin A (UA), a gut microbiome-derived postbiotic that enhances mitophagy, to ameliorate both age-related decline in cardiac function and cardiac failure. We highlight the significance of targeting mitochondria, by comparing gene expression changes in aging human hearts and cardiomyopathies. UA oral administration successfully counteracts mitochondrial and cardiac dysfunctions in preclinical models of aging and heart failure. UA improves both systolic and diastolic heart functions, distinguishing it from other mitochondrial interventions. In cardiomyocytes, UA recovers mitochondrial ultrastructural defects and decline in mitochondrial biomarkers occurring with aging and disease. These findings extend UAs benefits to heart health, making UA a promising nutritional intervention to evaluate in the clinic to promote healthy cardiovascular function as we age.

cell biology↗