scholarly journals A novel systems biology approach to evaluate mouse models of late-onset Alzheimer’s disease

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Christoph Preuss ◽  
◽  
Ravi Pandey ◽  
Erin Piazza ◽  
Alexander Fine ◽  
...  

Abstract Background Late-onset Alzheimer’s disease (LOAD) is the most common form of dementia worldwide. To date, animal models of Alzheimer’s have focused on rare familial mutations, due to a lack of frank neuropathology from models based on common disease genes. Recent multi-cohort studies of postmortem human brain transcriptomes have identified a set of 30 gene co-expression modules associated with LOAD, providing a molecular catalog of relevant endophenotypes. Results This resource enables precise gene-based alignment between new animal models and human molecular signatures of disease. Here, we describe a new resource to efficiently screen mouse models for LOAD relevance. A new NanoString nCounter® Mouse AD panel was designed to correlate key human disease processes and pathways with mRNA from mouse brains. Analysis of the 5xFAD mouse, a widely used amyloid pathology model, and three mouse models based on LOAD genetics carrying APOE4 and TREM2*R47H alleles demonstrated overlaps with distinct human AD modules that, in turn, were functionally enriched in key disease-associated pathways. Comprehensive comparison with full transcriptome data from same-sample RNA-Seq showed strong correlation between gene expression changes independent of experimental platform. Conclusions Taken together, we show that the nCounter Mouse AD panel offers a rapid, cost-effective and highly reproducible approach to assess disease relevance of potential LOAD mouse models.

2019 ◽  
Author(s):  
Christoph Preuss ◽  
Ravi Pandey ◽  
Erin Piazza ◽  
Alexander Fine ◽  
Asli Uyar ◽  
...  

ABSTRACTBackgroundLate-onset Alzheimer’s disease (LOAD) is the most common form of dementia worldwide. To date, animal models of Alzheimer’s have focused on rare familial mutations, due to a lack of frank neuropathology from models based on common disease genes. Recent multi-cohort studies of postmortem human brain transcriptomes have identified a set of 30 gene co-expression modules associated with LOAD, providing a molecular catalog of relevant endophenotypes.ResultsThis resource enables precise gene-based alignment between new animal models and human molecular signatures of disease. Here, we describe a new resource to efficiently screen mouse models for LOAD relevance. A new NanoString nCounter® Mouse AD panel was designed to correlate key human disease processes and pathways with mRNA from mouse brains. Analysis of three mouse models based on LOAD genetics, carrying APOE4 and TREM2*R47H alleles, demonstrated overlaps with distinct human AD modules that, in turn, are functionally enriched in key disease-associated pathways. Comprehensive comparison with full transcriptome data from same-sample RNA-Seq shows strong correlation between gene expression changes independent of experimental platform.ConclusionsTaken together, we show that the nCounter Mouse AD panel offers a rapid, cost-effective and highly reproducible approach to assess disease relevance of potential LOAD mouse models.


2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Ravi S. Pandey ◽  
Leah Graham ◽  
Asli Uyar ◽  
Christoph Preuss ◽  
Gareth R. Howell ◽  
...  

Abstract Background New genetic and genomic resources have identified multiple genetic risk factors for late-onset Alzheimer’s disease (LOAD) and characterized this common dementia at the molecular level. Experimental studies in model organisms can validate these associations and elucidate the links between specific genetic factors and transcriptomic signatures. Animal models based on LOAD-associated genes can potentially connect common genetic variation with LOAD transcriptomes, thereby providing novel insights into basic biological mechanisms underlying the disease. Methods We performed RNA-Seq on whole brain samples from a panel of six-month-old female mice, each carrying one of the following mutations: homozygous deletions of Apoe and Clu; hemizygous deletions of Bin1 and Cd2ap; and a transgenic APOEε4. Similar data from a transgenic APP/PS1 model was included for comparison to early-onset variant effects. Weighted gene co-expression network analysis (WGCNA) was used to identify modules of correlated genes and each module was tested for differential expression by strain. We then compared mouse modules with human postmortem brain modules from the Accelerating Medicine’s Partnership for AD (AMP-AD) to determine the LOAD-related processes affected by each genetic risk factor. Results Mouse modules were significantly enriched in multiple AD-related processes, including immune response, inflammation, lipid processing, endocytosis, and synaptic cell function. WGCNA modules were significantly associated with Apoe−/−, APOEε4, Clu−/−, and APP/PS1 mouse models. Apoe−/−, GFAP-driven APOEε4, and APP/PS1 driven modules overlapped with AMP-AD inflammation and microglial modules; Clu−/− driven modules overlapped with synaptic modules; and APP/PS1 modules separately overlapped with lipid-processing and metabolism modules. Conclusions This study of genetic mouse models provides a basis to dissect the role of AD risk genes in relevant AD pathologies. We determined that different genetic perturbations affect different molecular mechanisms comprising AD, and mapped specific effects to each risk gene. Our approach provides a platform for further exploration into the causes and progression of AD by assessing animal models at different ages and/or with different combinations of LOAD risk variants.


2021 ◽  
Vol 13 ◽  
Author(s):  
Adrian L. Oblak ◽  
Peter B. Lin ◽  
Kevin P. Kotredes ◽  
Ravi S. Pandey ◽  
Dylan Garceau ◽  
...  

The ability to investigate therapeutic interventions in animal models of neurodegenerative diseases depends on extensive characterization of the model(s) being used. There are numerous models that have been generated to study Alzheimer’s disease (AD) and the underlying pathogenesis of the disease. While transgenic models have been instrumental in understanding AD mechanisms and risk factors, they are limited in the degree of characteristics displayed in comparison with AD in humans, and the full spectrum of AD effects has yet to be recapitulated in a single mouse model. The Model Organism Development and Evaluation for Late-Onset Alzheimer’s Disease (MODEL-AD) consortium was assembled by the National Institute on Aging (NIA) to develop more robust animal models of AD with increased relevance to human disease, standardize the characterization of AD mouse models, improve preclinical testing in animals, and establish clinically relevant AD biomarkers, among other aims toward enhancing the translational value of AD models in clinical drug design and treatment development. Here we have conducted a detailed characterization of the 5XFAD mouse, including transcriptomics, electroencephalogram, in vivo imaging, biochemical characterization, and behavioral assessments. The data from this study is publicly available through the AD Knowledge Portal.


2019 ◽  
Author(s):  
Ravi S. Pandey ◽  
Leah Graham ◽  
Asli Uyar ◽  
Christoph Preuss ◽  
Gareth R. Howell ◽  
...  

ABSTRACTBackgroundNew genetic and genomic resources have identified multiple genetic risk factors for late-onset Alzheimer’s disease (LOAD) and characterized this common dementia at the molecular level. Experimental studies in model organisms can validate these associations and elucidate the links between specific genetic factors and transcriptomic signatures. Animal models based on LOAD-associated genes can potentially connect common genetic variation with LOAD transcriptomes, thereby providing novel insights into basic biological mechanisms underlying the disease.MethodsWe performed RNA-Seq on whole brain samples from a panel of six-month-old female mice, each carrying one of the following mutations: homozygous deletions of Apoe and Clu; hemizygous deletions of Bin1 and Cd2ap; and a transgenic APOEε4. Similar data from a transgenic APP/PS1 model was included for comparison to early-onset variant effects. Weighted gene co-expression network analysis (WGCNA) was used to identify modules of correlated genes and each module was tested for differential expression by strain. We then compared mouse modules with human postmortem brain modules from the Accelerating Medicine’s Partnership for AD (AMP-AD) to determine the LOAD-related processes affected by each genetic risk factor.ResultsMouse modules were significantly enriched in multiple AD-related processes, including immune response, inflammation, lipid processing, endocytosis, and synaptic cell function. WGCNA modules were significantly associated with Apoe−/−, APOEε4, Clu−/−, and APP/PS1 mouse models. Apoe−/−, GFAP-driven APOEε4, and APP/PS1 driven modules overlapped with AMP-AD inflammation and microglial modules; Clu−/− driven modules overlapped with synaptic modules; and APP/PS1 modules separately overlapped with lipid-processing and metabolism modules.ConclusionsThis study of genetic mouse models provides a basis to dissect the role of AD risk genes in relevant AD pathologies. We determined that different genetic perturbations affect different molecular mechanisms comprising AD, and mapped specific effects to each risk gene. Our approach provides a platform for further exploration into the causes and progression of AD by assessing animal models at different ages and/or with different combinations of LOAD risk variants.


2016 ◽  
Vol 8 (332) ◽  
pp. 332ra44-332ra44 ◽  
Author(s):  
Chia-Chen Liu ◽  
Na Zhao ◽  
Yu Yamaguchi ◽  
John R. Cirrito ◽  
Takahisa Kanekiyo ◽  
...  

Accumulation of amyloid-β (Aβ) peptide in the brain is the first critical step in the pathogenesis of Alzheimer’s disease (AD). Studies in humans suggest that Aβ clearance from the brain is frequently impaired in late-onset AD. Aβ accumulation leads to the formation of Aβ aggregates, which injure synapses and contribute to eventual neurodegeneration. Cell surface heparan sulfates (HSs), expressed on all cell types including neurons, have been implicated in several features in the pathogenesis of AD including its colocalization with amyloid plaques and modulatory role in Aβ aggregation. We show that removal of neuronal HS by conditional deletion of the Ext1 gene, which encodes an essential glycosyltransferase for HS biosynthesis, in postnatal neurons of amyloid model APP/PS1 mice led to a reduction in both Aβ oligomerization and the deposition of amyloid plaques. In vivo microdialysis experiments also detected an accelerated rate of Aβ clearance in the brain interstitial fluid, suggesting that neuronal HS either inhibited or represented an inefficient pathway for Aβ clearance. We found that the amounts of various HS proteoglycans (HSPGs) were increased in postmortem human brain tissues from AD patients, suggesting that this pathway may contribute directly to amyloid pathogenesis. Our findings have implications for AD pathogenesis and provide insight into therapeutic interventions targeting Aβ-HSPG interactions.


2021 ◽  
Vol 22 (23) ◽  
pp. 13168
Author(s):  
Natasha Elizabeth Mckean ◽  
Renee Robyn Handley ◽  
Russell Grant Snell

Alzheimer’s disease (AD) is one of the looming health crises of the near future. Increasing lifespans and better medical treatment for other conditions mean that the prevalence of this disease is expected to triple by 2050. The impact of AD includes both the large toll on individuals and their families as well as a large financial cost to society. So far, we have no way to prevent, slow, or cure the disease. Current medications can only alleviate some of the symptoms temporarily. Many animal models of AD have been created, with the first transgenic mouse model in 1995. Mouse models have been beset by challenges, and no mouse model fully captures the symptomatology of AD without multiple genetic mutations and/or transgenes, some of which have never been implicated in human AD. Over 25 years later, many mouse models have been given an AD-like disease and then ‘cured’ in the lab, only for the treatments to fail in clinical trials. This review argues that small animal models are insufficient for modelling complex disorders such as AD. In order to find effective treatments for AD, we need to create large animal models with brains and lifespan that are closer to humans, and underlying genetics that already predispose them to AD-like phenotypes.


2019 ◽  
Vol 15 ◽  
pp. P612-P613
Author(s):  
Christoph Preuss ◽  
Ravi S. Pandey ◽  
Alexander Fine ◽  
Asli Uyar ◽  
Benjamin A. Logsdon ◽  
...  

2019 ◽  
Vol 11 (476) ◽  
pp. eaar4289 ◽  
Author(s):  
Matt Kaeberlein ◽  
Veronica Galvan

The drug rapamycin has beneficial effects in a number of animal models of neurodegeneration and aging including mouse models of Alzheimer’s disease. Despite its compelling preclinical record, no clinical trials have tested rapamycin or other mTOR inhibitors in patients with Alzheimer’s disease. We argue that such clinical trials should be undertaken.


2016 ◽  
Vol 12 ◽  
pp. P196-P197
Author(s):  
Holly N. Cukier ◽  
Brian W. Kunkle ◽  
Sophie Rolati ◽  
Patrice L. Whitehead ◽  
Jeffery M. Vance ◽  
...  

2021 ◽  
pp. 1-15
Author(s):  
Luisa Müller ◽  
Timo Kirschstein ◽  
Rüdiger Köhling ◽  
Angela Kuhla ◽  
Stefan Teipel

Transgenic mouse models serve a better understanding of Alzheimer’s disease (AD) pathogenesis and its consequences on neuronal function. Well-known and broadly used AD models are APPswe/PS1dE9 mice, which are able to reproduce features of amyloid-β (Aβ) plaque formations as well as neuronal dysfunction as reflected in electrophysiological recordings of neuronal hyperexcitability. The most prominent findings include abnormal synaptic function and synaptic reorganization as well as changes in membrane threshold and spontaneous neuronal firing activities leading to generalized excitation-inhibition imbalances in larger neuronal circuits and networks. Importantly, these findings in APPswe/PS1dE9 mice are at least partly consistent with results of electrophysiological studies in humans with sporadic AD. This underscores the potential to transfer mechanistic insights into amyloid related neuronal dysfunction from animal models to humans. This is of high relevance for targeted downstream interventions into neuronal hyperexcitability, for example based on repurposing of existing antiepileptic drugs, as well as the use of combinations of imaging and electrophysiological readouts to monitor effects of upstream interventions into amyloid build-up and processing on neuronal function in animal models and human studies. This article gives an overview on the pathogenic and methodological basis for recording of neuronal hyperexcitability in AD mouse models and on key findings in APPswe/PS1dE9 mice. We point at several instances to the translational perspective into clinical intervention and observation studies in humans. We particularly focus on bi-directional relations between hyperexcitability and cerebral amyloidosis, including build-up as well as clearance of amyloid, possibly related to sleep and so called glymphatic system function.


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