Figure 3. Perturbed glymphatic function and exacerbated AQP4 perivascular localization (polarization) in the manifest zQ175 HD mouse brain.

(A) Representative images of DGE signals (lower panel) in a WT mouse and a zQ175 mouse at 10 months of age. (B) Average dynamic d-glucose signals during the entire scan period from male WT and zQ75 mice. n = 5 mice/genotype. (C) Comparison of fitted clearance parameter μ_out d-glucose clearance rate in CSF of the third ventricle. **P < 0.01 vs. WT by standard Student’s t test. (D) Comparison of fitted clearance parameter μ_in d-glucose uptake rate in CSF of the third ventricle. (E) Representative images of coimmunofluorescence staining of AQP4 and collagen IV in the striatum (upper panel) and cortex (bottom panel) of 10-month-old male zQ175 and WT controls. Scale bar = 100 μm. (F) Quantification of colocalized pixels of AQP4 (green in E) and collagen IV (red in E) in the striatum of 10-month-old male zQ175 mice and WT controls. *P < 0.05 vs. WT by standard Student’s t test. (G) Quantification of colocalized pixels of AQP4 (green in E) and collagen IV (red in E) in the cortex of 10-month-old male zQ175 mice and WT controls. **P < 0.01 vs. WT by standard Student’s t test. (H) Representative images of BSA-647 fluorescent dye distribution in the brain parenchyma at 60 minutes after intra-CM injection in 10-month-old mice. Scale bar = 1 cm. The left panel shows the BSA-647 fluorescence images, and the right panel shows BSA-647 fluorescence images merged with DAPI staining images. (I) Quantification of the fluorescent dye distribution at 60 minutes after CSF tracer injection. *P < 0.05 vs. WT by standard Student’s t test.