Figure 8

Vascular endothelial damage in the APP-tg mouse. Immunofluorescence staining of hepcidin and ferroportin with endothelial markers CD31 and PDGFβR1 was performed using brain sections from lateral ventricles, choroid plexus and blood vessels. In control mice, hepcidin staining was detected in ependymal cells of lateral ventricles at 4 months (a), the choroid plexus at 10 months-old where hepcidin and FPN both co-localised in epithelial cells, with higher FPN expression on the ventricular side ( white arrow, b). Hepcidin was present in endothelial cells in blood vessels (c). Hepcidin staining was visible in epithelial cells of choroid plexus where as ApoE was found in the blood vessel wall (c). There was no vessel damage noticed in 4 months old APP-tg mouse choroid plexus stained with ApoE and FPN (d), whereas by 10 months more vascular damage was apparent (e). Similarly sections close to the lateral ventricle of APP-Tg mice were stained with ApoE and FPN (h), ApoE and hepcidin (i) indicating extensive endothelial damage. Blood vessel integrity was assessed with CD31 and PDGFβR1 markers, with intact endothelium and pericytes were observed in controls (g) while badly damaged endothelia was seen in APP-tg mice at 10 months (f) and (j). In another section from APP-tg thalamus stained with ApoE and CD31 showed a complete loss of endothelial layer at 10 months (k). Hepcidin and ApoE co-localised in large blood vessels (l). Scale bar a-b, 100 μm, c 25 μm, d-f and h-k 75 μm, g and l 50 μm.