Fig. 4
Beta-amyloid uptake in capillaries and venules of Tg2576 mice is significantly decreased. a, Single frames of capillaries 30 min after perfusing 5-FAM-tagged Aβ monomers in WT and Tg2576 murine vasculature with/without inhibiting RAGE transporter by 10 µM FPS-ZM1. All images are displayed in parallel as fluorescence scan, laser DIC scan and an overlay of both. In WT mice, Aβ fluorescence is localized at the luminal walls (arrow heads) under control conditions, which significantly decreased after RAGE inhibition by FPS-ZM1 (see b). In Tg2576 mice, negligible Aβ uptake was noted under both experimental conditions (see b). An example of line profiles used for analysis is shown (grey line, 3-µm thick). Asterisks signify ECs, while yellow arrows refer to autofluorescence commonly found in aged tissue. b, Quantification of luminal fluorescence intensities in capillaries under control conditions (nROI WT mice = 14, nROI Tg2576 mice = 16) and RAGE inhibition (nROI WT mice = 11, nROI Tg2576 mice = 12) represented as mean ± SEM (two-way ANOVA, *P < 0.05; ns, insignificant, see supplementary information). c, Single frames of venules after perfusing 5-FAM-tagged Aβ monomers for 30 min under control conditions and after preincubation with 10 µM FPS-ZM1 in WT and Tg2576 murine vasculature. In WT mouse brain tissue under no-blocking condition, Aβ fluorescence is localized within the luminal walls (arrow heads), which significantly decreased upon inhibiting RAGE with FPS-ZM1 (see d). Significantly lower Aβ uptake was recorded in Tg2576 venules, which remained unaltered after applying FPS-ZM1 to block RAGE (see d). An example of the analyzed line profile is indicated (grey line, 3-µm thick). Similarly, ECs are marked by asterisks, while yellow arrows indicate autofluorescence. d, Quantification of luminal fluorescence in venules under no-blocking condition (nROI WT mice = 13, nROI Tg2576 mice = 19) and RAGE inhibition (nROI WT mice = 7, nROI Tg2576 mice = 14) represented as mean ± SEM. (two-way ANOVA, *P < 0.05; ns, insignificant, see supplementary information). Data were collected from 10 injections/4 animals