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The Latest Articles on Mouse Models of Alzheimer’s Diseases

Published on: 1 Feb 2024 Viewed: 279

Our staff editors continue to share exciting, interesting, and thought-provoking reading material in the recommended articles series.

This week, we would like to share several latest articles on mouse models of Alzheimer’s diseases.

Title: Cognitive impairment in Alzheimer's disease FAD4T mouse model: Synaptic loss facilitated by activated microglia via C1qA
Authors: Cui Zhang, Hao Qi, Dongjing Jia, Jingting Zhao, Chengyuan Xu, Jing Liu, Yangfeng Cui, Jiajian Zhang, Minzhe Wang, Ming Chen, Binliang Tang
Type: Research Article

Abstract:
Alzheimer's disease (AD) is a chronic and progressive neurodegenerative disorder characterized by cognitive dysfunction. The connection between neuroinflammation and abnormal synaptic function in AD is recognized, but the underlying mechanisms remain unclear. In this study, we utilized a mouse model of AD, FAD4T mice aged 6–7 months, to investigate the molecular changes affecting cognitive impairment. Behavior tests showed that FAD4T mice exhibited impaired spatial memory compared with their wild-type littermates. Immunofluorescence staining revealed the presence of Aβ plaques and abnormal glial cell activation as well as changes in microglial morphology in the cortex and hippocampus of FAD4T mice. Synaptic function was impaired in FAD4T mice. Patch clamp recordings of hippocampal neurons revealed reduced amplitude of miniature excitatory postsynaptic currents. Additionally, Golgi staining showed decreased dendritic spine density in the cortex and hippocampus of FAD4T mice, indicating aberrant synapse morphology. Moreover, hippocampal PSD-95 and NMDAR1 protein levels decreased in FAD4T mice. RNA-seq analysis revealed elevated expression of immune system and proinflammatory genes, including increased C1qA protein and mRNA levels, as well as higher expression of TNF-α and IL-18. Taken together, our findings suggest that excessive microglia activation mediated by complement factor C1qA may contribute to aberrant synaptic pruning, resulting in synapse loss and disrupted synaptic transmission, ultimately leading to AD pathogenesis and behavioral impairments in the FAD4T mouse model. Our study provides valuable insights into the underlying mechanisms of cognitive impairments and preliminarily explores a potentially effective treatment approach targeting on C1qA for AD.
Access this article: https://doi.org/10.1016/j.lfs.2024.122457

Title: Upregulation of Integrin beta-3 in astrocytes upon Alzheimer's disease progression in the 5xFAD mouse model
Authors: Mariia Ivanova, Irina Belaya, Nina Kucháriková, Izaque de Sousa Maciel, Liudmila Saveleva, Arto Alatalo, Ilona Juvonen, Navjot Thind, Clarisse Andrès, Riikka Lampinen, Sweelin Chew, Katja M. Kanninen
Type: Research Article

Abstract
Integrins are receptors that have been linked to various brain disorders, including Alzheimer's disease (AD), the most prevalent neurodegenerative disorder. While Integrin beta-3 (ITGB3) is known to participate in multiple cellular processes such as adhesion, migration, and signaling, its specific role in AD remains poorly understood, particularly in astrocytes, the main glial cell type in the brain. In this study, we investigated alterations in ITGB3 gene and protein expression during aging in different brain regions of the 5xFAD mouse model of AD and assessed the interplay between ITGB3 and astrocytes. Primary cultures from adult mouse brains were used to gain further insight into the connection between ITGB3 and amyloid beta (Aβ) in astrocytes. In vivo studies showed a correlation between ITGB3 and the astrocytic marker GFAP in the 5xFAD brains, indicating its association with reactive astrocytes. In vitro studies revealed increased gene expression of ITGB3 upon Aβ treatment. Our findings underscore the potential significance of ITGB3 in astrocyte reactivity in the context of Alzheimer's disease.
Access this article: https://doi.org/10.1016/j.nbd.2024.106410

Title: Behavioral, metabolic, and lipidomic characterization of the 5xFADxTg30 mouse model of Alzheimer’s disease
Authors: J.P.S. Marshall, K. Huynh, G.I. Lancaster, J. Ng, J.M. Collins, G. Pernes, A. Liang, T. Featherby, N.A. Mellet, B.G. Drew, A.C. Calkin, A.E. King, P.J. Meikle, M.A. Febbraio, P.A. Adlard, D.C. Henstridge
Type: Research Article

Summary
Alzheimer’s disease (AD) is associated with both extracellular amyloid-β (Aβ) plaques and intracellular tau-containing neurofibrillary tangles (NFT). We characterized the behavioral, metabolic and lipidomic phenotype of the 5xFADxTg30 mouse model which contains overexpression of both Aβ and tau. Our results independently reproduce several phenotypic traits described previously for this model, while providing additional characterization. This model develops many aspects associated with AD including frailty, decreased survival, initiation of aspects of cognitive decline and alterations to specific lipid classes and molecular lipid species in the plasma and brain. Notably, some sex-specific differences exist in this model and motor impairment with aging in this model does compromise the utility of the model for some movement-based behavioral assessments of cognitive function. These findings provide a reference for individuals interested in using this model to understand the pathology associated with elevated Aβ and tau or for testing potential therapeutics for the treatment of AD.
Access this article: https://doi.org/10.1016/j.isci.2024.108800

Title: Protective effect of scallop-derived plasmalogen against vascular dysfunction, via the pSTAT3/PIM1/NFATc1 axis, in a novel mouse model of Alzheimer’s disease with cerebral hypoperfusion
Authors: Yun Zhai, Ryuta Morihara, Tian Feng, Xinran Hu, Yusuke Fukui, Zhihong Bian, Yuting Bian, Haibo Yu, Hongming Sun, Mami Takemoto, Yumiko Nakano, Taijun Yunoki, Ying Tang, Hiroyuki Ishiura, Toru Yamashita
Type: Research Article

Abstract:
A strong relationship between Alzheimer’s disease (AD) and vascular dysfunction has been the focus of increasing attention in aging societies. In the present study, we examined the long-term effect of scallop-derived plasmalogen (sPlas) on vascular remodeling-related proteins in the brain of an AD with cerebral hypoperfusion (HP) mouse model. We demonstrated, for the first time, that cerebral HP activated the axis of the receptor for advanced glycation endproducts (RAGE)/phosphorylated signal transducer and activator of transcription 3 (pSTAT3)/provirus integration site for Moloney murine leukemia virus 1 (PIM1)/nuclear factor of activated T cells 1 (NFATc1), accounting for such cerebral vascular remodeling. Moreover, we also found that cerebral HP accelerated pSTAT3-mediated astrogliosis and activation of the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome, probably leading to cognitive decline. On the other hand, sPlas treatment attenuated the activation of the pSTAT3/PIM1/NFATc1 axis independent of RAGE and significantly suppressed NLRP3 inflammasome activation, demonstrating the beneficial effect on AD.
Access this article: https://doi.org/10.1016/j.brainres.2024.148790

Title: Protective effect of a hydromethanolic extract from Fraxinus excelsior L. bark against a rat model of aluminum chloride-induced Alzheimer's disease: Relevance to its anti-inflammatory and antioxidant effects
Authors: Amin Iranpanah, Sajad Fakhri, Gholamreza Bahrami, Mohammad Bagher Majnooni, Mohammad Mehdi Gravandi, Sara Taghavi, Mehdi Azadi Badrbani, Roshanak Amirian, Mohammad Hosein Farzaei
Type: Research Article

Abstract:

Ethnopharmacological relevance
Fraxinus excelsior L. (FE), commonly known as the ash, belongs to the Oleaceae family and has shown several pharmacological and biological properties, such as antioxidant, immunomodulatory, neuroprotective, and anti-inflammatory effects. It has also attracted the most attention toward neuroinflammation. Moreover, FE bark and leaves have been used to treat neurological disorders, aging, neuropathic pain, urinary complaints, and articular pain in traditional and ethnomedicine. Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder resulting from the involvement of amyloid-beta, metal-induced oxidative stress, and neuroinflammation.

Aim of the study
The objective of the current study was to assess the neuroprotective effects of hydromethanolic extract from FE bark in an AlCl3-induced rat model of AD.

Materials and methods
The maceration process was utilized to prepare the hydromethanolic extract of FE bark, and characterized by LC-MS/MS. To assess the anti-AD effects of the FE extract, rats were categorized into five different groups, AlCl3; normal control; FE-treated groups at 50, 100, and 200 mg/kg. Passive avoidance learning test, Y-maze, open field, and elevated plus maze behavioral tests were evaluated on days 7 and 14 to analyze the cognitive impairments. Zymography analysis, biochemical tests, and histopathological changes were also followed in different groups.

Results
LC-MS/MS analysis indicated the presence of coumarins, including isofraxidin7-O-diglucoside in the methanolic extract of FE as a new isofraxidin derivative in this genus. FE significantly improved memory and cognitive function, maintained weight, prevented neuronal damages, and preserved the hippocampus's histological features, as demonstrated by behavioral tests and histopathological analysis. FE increased anti-inflammatory MMP-2 activity, whereas it decreased that of inflammatory MMP-9. Moreover, FE increased plasma antioxidant capacity by enhancing CAT and GSH while decreasing nitrite levels in the serum of treated groups. In comparison between the treated groups, the rats that received high doses of the FE extract (200 mg/kg) showed the highest therapeutic effect.

Conclusion    
FE rich in coumarins could be an effective anti-AD adjunct agent, passing through antioxidant and anti-inflammatory pathways. These results encourage further studies for the development of this extract as a promising agent in preventing, managing, or treating AD and related diseases.

Access this article: https://doi.org/10.1016/j.jep.2024.117708

Ageing and Neurodegenerative Diseases
ISSN 2769-5301 (Online)

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All published articles will be preserved here permanently:

https://www.portico.org/publishers/oae/