Fig. 3: Angiogenesis is non-productive around Aß plaques.

a Working model of the angiogenesis around Aß plaques. Numeration continues from Fig. 1f. Upper row: Non-productive angiogenesis will convert phalanx cells to non-conducting tip cells, extending local hypoxia (5). Lower row: γ-secretase activity is involved in the lateral inhibition process that controls tip-stalk cell identity. b, c Gene set enrichment analysis (GSEA) revealed that Dll4+/–_Up GS is highly represented in 18-month-old APP-PSEN1/+ versus WT endothelial cell differential transcriptomic (b, left panel). Right panel (b) shows the heat map of the top 30 ranking leading edge genes included in the Dll4+/–_Up GS. Red symbolizes overexpression and blue down regulation. The table includes the eight top-enriched GSs (c), FEWER p val (values) were two-sided and adjusted for multiple comparisons. d Cortical confocal XY images from 8-month-old APP-PSEN1/+ and stained with endothelial (IB4; red), Plaur (ISH; brown), Aß (Thio-S; green), and nuclear (DAPI; blue) markers. Arrowheads indicate reactive cells expressing Plaur. Scale bar = 20 µm. Right graph shows the quantification of Plaur⁺ cells/mm² in WT (gray dots) and distal to Aß plaques (D; light blue dots) and IB4⁺ regions (IB4⁺; blue dots) in the APP-PSEN1/+ mouse model. Mean ± SEM. n = 4 WT and 3 APP-PSEN1/+ mice; ANOVA, post hoc Tukey’s test. e Cortical confocal projection from 8- (upper row) and 12- (lower row) month-old APP-PSEN1/+ mice injected with Evans Blue (EB, white) and stained with endothelial (IB4; red) and nuclear (DAPI; blue) markers. Aß plaques are indicated with a yellow asterisk. Scale bar = 20 µm. f Full hemi-cortex from a 10-month-old APP-PSEN1/+ mouse stained to visualize endothelial cells (IB4; red) and rendered transparent using iDISCO. Scale bar = 500 µm. g Superimages of brain cortical sections from WT, APP-PSEN1/+, and APP₇₅₁SL/+ mice stained to label endothelial cells (IB4; red). Insets show the white square from low magnification images. Scale bar = 1 mm in low and 500 µm in high magnification images. h Quantification of the percentage of cortical surface occupied by abnormal IB4⁺ staining. Mean ± SEM. n = 3 8-month-old WT and APP-PSEN1/+; and 12-month-old APP-PSEN1/+; and 6 APP₇₅₁SL/+ mice; ANOVA, post hoc Tukey’s test. i Image of a cortical slice from 8-month-old APP-PSEN1/+ mice stained with endothelial (IB4; red), Aß (Thio-S; green), and nuclear (DAPI; blue) markers. Scale bar = 100 µm. j Schematic representation of the Cp-HIST1H2BB::Venus/+ mouse model. NICD NOTCH intracellular domain, CBF1 BS CBF1-binding sites. k Left images: coronal cortical sections from Cp-HIST1H2BB::Venus/+; APP-PSEN1/+ mice distal (left) and proximal (right) to Aß plaques and stained with endothelial (IB4; red), and nuclear (DAPI; blue) markers. Green: Direct visualization of H2BB::Venus fluorescence. Scale bar = 20 µm. Right graph, quantification of the number of H2BB::Venus positive endothelial cells in Cp-HIST1H2BB::Venus/+; +/+ (Control, C), Cp-HIST1H2BB::Venus/+; APP-PSEN1/+ distal (D) and IB4⁺ proximal (P) to Aß plaques. Mean ± SEM. n = 3 Cp-HIST1H2BB::Venus/+; +/+ and 6 Cp-HIST1H2BB::Venus/+; APP-PSEN1/+ mice; ANOVA, post hoc Tukey’s test.