Fig. 1
The plasma levels of Aβ1-42 and brain deposition of Aβ after parabiotic surgery. a Schematic diagram depicting the parabiotic pairings. A pair of 3 months-old female Tg mice and age-matched female Wt littermates were used for parabiosis. A pair of 3 months-old female Wt mice were used for parabiotic controls. Samples were collected for analysis at 7 and 11 months of age. Age-matched female Tg and Wt mice without parabiosis were also explored. b The mice after parabiotic surgery. c Plasma Aβ42 levels in Wt, PaWt(Wt-Wt), PaWt(Wt-Tg), PaTg(Wt-Tg), and Tg mice at the age of 7 and 11 months. At the age of 7 months, the plasma Aβ42 levels in Tg mice were significantly higher than Wt mice (p = 0.000), the plasma Aβ42 levels in PaWt(Wt-Tg) mice were significantly higher than PaWt(Wt-Wt) mice (p = 0.000), the plasma Aβ42 levels in PaTg(Wt-Tg) mice were higher than PaWt(Wt-Tg) mice (p = 0.041). At the age of 11 months, the plasma Aβ42 levels in Tg mice were significantly higher than Wt mice (p = 0.000), the plasma Aβ42 levels in PaWt(Wt-Tg) mice were significantly higher than PaWt(Wt-Wt) mice (p = 0.000), the plasma Aβ42 levels in PaTg(Wt-Tg) mice were higher than PaWt(Wt-Tg) mice (p = 0.581). d Representative images of amyloid deposition stained with 6E10 in neocortex and hippocampus of PaWt(Wt-Wt), PaWt(Wt-Tg), PaTg(Wt-Tg), and Tg mice brain at the age of 7 and 11 months respectively. Scale bars 2500 µm. e The quantifications of the Aβ plaques (6E10Area fraction (%)) in the neocortex and hippocampus were 1.58 ± 0.57% in Tg mice, 1.13 ± 0.35% in PaTg(Wt-Tg) mice, 0.40 ± 0.05% in PaWt(Wt-Tg) mice, and 0.32 ± 0.04% in PaWt(Wt-Wt) mice, respectively at the age of 7 months. At the age of 11 months the quantifications of the Aβ plaques in the neocortex and hippocampus were 8.13 ± 1.25% in Tg mice,3.03 ± 0.88% in PaTg(Wt-Tg) mice, 1.24 ± 0.44% in PaWt(Wt-Tg) mice, and 0.40 ± 0.06% in PaWt(Wt-Wt) mice, respectively.At the age of 7 months, the Aβ plaques in the neocortex and hippocampus had no significant difference between PaWt(Wt-Tg) mice and PaWt(Wt-Wt) mice (p = 0.114), and Tg mice and PaTg(Wt-Tg) mice (p = 0.200). The Aβ plaques in the neocortex and hippocampus of PaWt(Wt-Tg) were higher compared with PaWt(Wt-Wt) (p = 0.029), and in Tg mice the Aβ plaques in the neocortex and hippocampus were higher compared with PaTg(Wt-Tg) mice (p = 0.029). f Bioluminescent images of Wt mice after tail intravenous injection with hAβ42 labeled with HiLyte Fluor 488 1 h. (n = 6, Mean ± SD, one-way analysis of variance. ***P < 0.001, **P < 0.01, ns denotes no statistical significance)