Data and code for "APOE4 and sedentary lifestyle synergistically impair neurovascular function in the visual cortex of awake mice"

<b>Data and code for </b><b>analysing data presented in</b><b> paper published in Communications Biology (January 2025)</b>Each .csv file contains data for the figures from the paper, as listed in the file name. R Markdown code is provided to generate the figures from the provided .csv files. Please use R and R Studio to run the R Markdown files. Files were produced with R version 4.4.2 and R Markdown, Version 2024.12.0+467.The overall study compares various aspects of neurovascular physiology between APOE3 and APOE4 mice which have had differential access to an exercise wheel. The figures each contain the following data:Figure 1 and Supplementary Figure 1: Mouse weights and activity levels.Figure 2 and Supplementary Figure 2: Vascular and pericyte densities and diameters. Baseline haemodynamic properties in visual cortex.Figure 3: Pial vessel vasomotion.Figure 4 and Supplementary Figure 3: Changes in haemodynamic parameters during visual stimulation.Figure 5 and Supplementary Figure 4: Vascular dilation and red blood cell velocity changes during visual stimulation.FIgure 6 and Supplementary Figure 5: Calcium signals and neurovascular coupling indices in visual cortex.Figure 7 and Supplementary Figure 6: Correlations between physical activity levels and the data presented in the previous figures.Supplementary Figure 7: Multivariate analyses across all variables.<br><b>Paper abstract:</b>Reduced cerebral blood flow occurs early in the development of Alzheimer’s disease (AD), but the factors producing this reduction are unknown. Here, we ask whether genetic and lifestyle risk factors for AD—the ε4 allele of the Apolipoprotein (APOE) gene, and physical activity—can together produce this reduction in cerebral blood flow which leads eventually to AD. Using in vivo two-photon microscopy and haemodynamic measures, we record neurovascular function from the visual cortex of physically active or sedentary mice expressing APOE3 and APOE4 in place of murine APOE. Energy supply and demand are mismatched in APOE4 mice, with smaller increases in cerebral blood flow, blood volume and blood oxygenation occurring during neuronal activation as blood vessels frequently fail to dilate. Exercise dose-dependently overall improves neurovascular function, with an increased impact of exercise apparent after longer exposure times. Several haemodynamic measures show a larger beneficial effect of exercise in APOE4 vs. APOE3 mice. Thus, APOE4 genotype in conjunction with sedentary behaviour produces the worst neurovascular function. Promotion of physical activity may therefore be particularly important to improve cerebrovascular function and reduce dementia risk in APOE4 carriers.<br>