Gene Expression Profiling in the APP/PS1KI Mouse Model of Familial Alzheimer’s Disease

Article type: Research Article

Authors: Weissmann, Robert^{a; 1} | Hüttenrauch, Melanie^{b; 1} | Kacprowski, Tim^c | Bouter, Yvonne^b | Pradier, Laurent^d | Bayer, Thomas A.^b | Kuss, Andreas W.^{a; *} | Wirths, Oliver^{b; *}

Affiliations: [a] Department of Human Genetics, University Medicine Greifswald and Interfaculty Institute of Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany | [b] Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Göttingen, Germany | [c] Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine and Ernst-Moritz-Arndt University Greifswald, Germany | [d] Sanofi, Therapeutic Strategy Unit Neurodegeneration and Pain, Chilly Mazarin, France

Correspondence: [*] Correspondence to: Oliver Wirths, PhD, Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University Göttingen, von-Siebold-Str. 5, 37075 Göttingen, Germany. Tel.: +49 551 3910290; Fax: +49 551 3910291; E-mail owirths@gwdg.de.

Correspondence: [*] Correspondence to: Andreas W. Kuss, PhD, Human Molecular Genetics, Institute for Human Genetics, University Medicine Greifswald, Ernst-Moritz-Arndt University Greifswald, Fleischmannstr. 42-44, 17475 Greifswald, Germany. Tel.: +49 3834 865359; Fax: +49 3834 865393; E-mail kussa@uni-greifswald.de.

Note: [1] These authors contributed equally to this work.

Abstract: Alzheimer’s disease (AD) is a devastating neurodegenerative disorder characterized by early intraneuronal amyloid-β (Aβ) accumulation, extracellular deposition of Aβ peptides, and intracellular hyperphosphorylated tau aggregates. These lesions cause dendritic and synaptic alterations and induce an inflammatory response in the diseased brain. Although the neuropathological characteristics of AD have been known for decades, the molecular mechanisms causing the disease are still under investigation. Studying gene expression changes in postmortem AD brain tissue can yield new insights into the molecular disease mechanisms. To that end, one can employ transgenic AD mouse models and the next-generation sequencing technology. In this study, a whole-brain transcriptome analysis was carried out using the well-characterized APP/PS1KI mouse model for AD. These mice display a robust phenotype reflected by working memory deficits at 6 months of age, a significant neuron loss in a variety of brain areas including the CA1 region of the hippocampus and a severe amyloid pathology. Based on deep sequencing, differentially expressed genes (DEGs) between 6-month-old WT or PS1KI and APP/PS1KI were identified and verified by qRT-PCR. Compared to WT mice, 250 DEGs were found in APP/PS1KI mice, while 186 DEGs could be found compared to PS1KI control mice. Most of the DEGs were upregulated in APP/PS1KI mice and belong to either inflammation-associated pathways or lysosomal activation, which is likely due to the robust intraneuronal accumulation of Aβ in this mouse model. Our comprehensive brain transcriptome study further highlights APP/PS1KI mice as a valuable model for AD, covering molecular inflammatory and immune responses.

Keywords: Alzheimer’s disease, amyloid, differential gene expression, next-generation sequencing, transcriptome, transgenic mice

DOI: 10.3233/JAD-150745

Journal: Journal of Alzheimer's Disease, vol. 50, no. 2, pp. 397-409, 2016