Affiliations: [a] Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Henan, China
| [b] Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| [c] Department of Pathology, The Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| [d] Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
Correspondence:
[*]
Correspondence to: Yuming Xu, Department of Neurology, The First Affiliated Hospital of Zhengzhou University, No.1 Eastern Jianshe Road, Zhengzhou 450052, Henan, China. Tel./Fax: +86 371 66862132; E-mail: xuyuming@zzu.edu.cn and Reidun Torp, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Box 1105, Blindern, N-0317 Oslo, Norway. Tel.: +47 22851052; Fax: +47 22851278; E-mail: reidun.torp@medisin.uio.no.
Note: [1] These authors contributed equally to this work.
Abstract: Amyloid-β deposition in senile plaques is one of the main pathological changes in Alzheimer’s disease (AD). We previously reported that aquaporin-4 (AQP4) is redistributed within the astrocytes in cerebral amyloid angiopathy in the tg-ArcSwe mouse model of AD, suggesting that AQP4 may participate in amyloid-β deposition. However, the role of AQP4 in plaque formation is not currently clear. The objective of the current study was to explore the AQP4 distribution within plaques in the tg-ArcSwe mice in more depth by the combined application of immunofluorescence cytochemistry and immunogold electron microscopy. In addition, the astrocyte marker, glial fibrillary acidic protein (GFAP), was studied in association with AQP4. We demonstrated a robust upregulation of AQP4 expression in areas of plaques. Compared to GFAP, AQP4 appeared predominantly at later stages of plaque formation, in older mice, and within the processes of astrocytes. In combination with GFAP, AQP4 differentiated plaques into three progression stages under light microscopy. This suggests that AQP4 expression was associated with amyloid deposition and astrocyte pathology in the Tg-ArcSwe mouse model of AD. This provides novel proof for the involvement of AQP4 in the process of amyloid deposition in AD.
