Figure 5.

Normalizing the circulating PDGF‐BB ameliorates hippocampal microvascular impairment and cognitive decline. A) ELISA analysis of serum PDGF‐BB concentration in 18‐month‐old Pdgfb^cKO mice and WT littermates. B) Pdgfb^cKO mice and WT littermates were fed HFD or CHD for 4 months, starting from 3 months of age. ELISA analysis of serum PDGF‐BB concentration. C) Representative confocal images of CD31 (green) and CD13 (red) double‐immunofluorescence staining in DG and CA1 region in 18‐month‐old Pdgfb^cKO mice and WT littermates. DAPI stains nuclei blue. Scale bar, 100 µm. D–F) Quantification of the percentage of vessel length (D), vessel area (E), and CD13⁺ pericyte coverage of the capillaries in hippocampus (F), n = 5. G) Representative confocal images of CD31 (green) and CD13 (red) double‐immunofluorescence staining in DG and CA1 region in CHD versus HFD Pdgfb^cKO mice. DAPI stains nuclei blue. Scale bar, 100 µm. H–J) Quantification of the percentage of vessel area (H), vessel length (I), and CD13⁺ pericyte coverage of the capillaries in hippocampus (J), n = 5. K) Representative immunofluorescence images of DG and CA1 region of hippocampus from mice of 18‐month‐old Pdgfb^cKO mice and WT littermates using antibody against albumin. DAPI stains nuclei as blue. Scale bar, 100 µm. L) Quantification of Albumin⁺ signal covered area using Image J. M,N) Cognitive mouse behaviors in CHD versus HFD Pdgfb^cKO mice were assessed. Mice were tested for spatial recognition (M) and spontaneous alternation (N) in Y‐maze. n = 10. *p<0.05, **p<0.01, ***p<0.001 as determined by unpaired two‐tailed Student's t test (for 2 group comparison) or One‐way ANOVA (for multiple group comparison).