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Boehm-Sturm, P.

Publications and source records attributed to Boehm-Sturm, P..

2 recordsLinked to original sources

Vascular cognitive impairment in the mouse reshapes visual, spatial network functional connectivity.

Connectome analysis of neuroimaging data is a rapidly expanding field to identify disease specific biomarkers. Structural diffusion MRI connectivity has been useful in individuals with radiological features of small vessel disease, such as white matter hyperintensities. Global efficiency, a network metric calculated from the structural connectome, is an excellent predictor of cognitive decline. To dissect the biological underpinning of these changes, animal models are required. We tested whether the structural connectome is altered in a mouse model of vascular cognitive impairment. White matter damage was more pronounced by 6 compared to 3 months. Global efficiency remained intact, but the visual association cortex exhibited increased structural connectivity with other brain regions. Exploratory resting state functional MRI connectivity analysis revealed diminished default mode network activity in the model compared to shams. Further perturbations were observed in a primarily cortical hub and the retrosplenial and visual cortices, and the hippocampus were the most affected nodes. Behavioural deficits were observed in the cued water maze, supporting the suggestion that the visual and spatial memory networks are affected. We demonstrate specific circuitry is rendered vulnerable to vascular stress in the mouse, and the model will be useful to examine pathophysiological mechanisms of small vessel disease. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

neuroscience

Selective inhibition of histone deacetylase 1 and 3 improves motor phenotype and alleviates transcriptional dysregulation in Huntington's disease mice

Huntingtons disease (HD) is an autosomal dominant neurodegenerative disease characterized by a late clinical onset of psychiatric, cognitive, and motor symptoms. Transcriptional dysregulation is an early and central disease mechanism which is accompanied by epigenetic alterations in HD. Previous studies demonstrated that targeting transcriptional changes by inhibition of histone deacetylases (HDACs), especially the class I HDACs, provides therapeutic effects. Yet, their exact mechanisms of action and the features of HD pathology, on which these inhibitors act remain to be elucidated. Here, using transcriptional profiling, we found that selective inhibition of HDAC1 and HDAC3 by RGFP109 repaired the expression of a number of genes, including the transcription factor genes Neurod2 and Nr4a2, and 43% of the gene sets that were dysregulated by mutant Huntingtin expression in the striatum and improved motor skill learning deficit in the R6/1 mouse model of HD. RGFP109-treated R6/1 mice showed improved coordination on the RotaRod over four consecutive trials, while vehicle-treated R6/1 animals displayed no improvement in coordination skills and fell 50 seconds earlier off the rod in the fourth trial. We also found, by volumetric MRI, a widespread brain atrophy in the R6/1 mice at the symptomatic disease stage, on which RGFP109 showed a modest effect. Collectively, our combined work presents new evidence for specific HDAC1 and HDAC3 inhibition as a therapeutic strategy for alleviating the phenotypic and molecular features of HD.

neuroscience