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L'Esperance OJ, McGhee J, Davidson G, Niraula S, Smith AS, Sosunov AA, Yan SS, Subramanian J. Functional Connectivity Favors Aberrant Visual Network c-Fos Expression Accompanied by Cortical Synapse Loss in a Mouse Model of Alzheimer's Disease. J Alzheimers Dis 2024:JAD240776. [PMID: 39121131 DOI: 10.3233/jad-240776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2024]
Abstract
Background While Alzheimer's disease (AD) has been extensively studied with a focus on cognitive networks, visual network dysfunction has received less attention despite compelling evidence of its significance in AD patients and mouse models. We recently reported c-Fos and synaptic dysregulation in the primary visual cortex of a pre-amyloid plaque AD-model. Objective We test whether c-Fos expression and presynaptic density/dynamics differ in cortical and subcortical visual areas in an AD-model. We also examine whether aberrant c-Fos expression is inherited through functional connectivity and shaped by light experience. Methods c-Fos+ cell density, functional connectivity, and their experience-dependent modulation were assessed for visual and whole-brain networks in both sexes of 4-6-month-old J20 (AD-model) and wildtype (WT) mice. Cortical and subcortical differences in presynaptic vulnerability in the AD-model were compared using ex vivo and in vivo imaging. Results Visual cortical, but not subcortical, networks show aberrant c-Fos expression and impaired experience-dependent modulation. The average functional connectivity of a brain region in WT mice significantly predicts aberrant c-Fos expression, which correlates with impaired experience-dependent modulation in the AD-model. We observed a subtle yet selective weakening of excitatory visual cortical synapses. The size distribution of cortical boutons in the AD-model is downscaled relative to those in WT mice, suggesting a synaptic scaling-like adaptation of bouton size. Conclusions Visual network structural and functional disruptions are biased toward cortical regions in pre-plaque J20 mice, and the cellular and synaptic dysregulation in the AD-model represents a maladaptive modification of the baseline physiology seen in WT conditions.
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Affiliation(s)
- Oliver J L'Esperance
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Joshua McGhee
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Garett Davidson
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Suraj Niraula
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Adam S Smith
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, USA
| | - Alexandre A Sosunov
- Department of Neurosurgery, Columbia University Medical Center, New York, NY, USA
| | - Shirley Shidu Yan
- Department of Neurosurgery, Columbia University Medical Center, New York, NY, USA
| | - Jaichandar Subramanian
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, USA
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2
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Vázquez-Durán DL, Ortega A, Rodríguez A. Amino Acid Transporters Proteins Involved in the Glutamate-Glutamine Cycle and Their Alterations in Murine Models of Alzheimer's Disease. Mol Neurobiol 2024; 61:6077-6088. [PMID: 38273046 DOI: 10.1007/s12035-024-03966-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
The brain's ability to integrate external stimuli and generate responses is highly complex. While these mechanisms are not completely understood, current evidence suggests that alterations in cellular metabolism and microenvironment are involved in some dysfunctions as complex as Alzheimer's disease. This pathology courses with defects in the establishment of chemical synapses, which is dependent on the production and supply of neurotransmitters like glutamate and its recycling through the glutamate-glutamine cycle. Alterations in the expression and function of the amino acid transporters proteins involved in this cycle have recently been reported in different stages of Alzheimer's disease. Most of these data come from patients in advanced stages of the disease or post-mortem, due to the ethical and technical limitations of human studies. Therefore, genetically modified mouse models have been an excellent tool to analyze metabolic and even behavioral parameters that are very similar to those that develop in Alzheimer's disease, even at presymptomatic stages. Hence, this paper analyzes the role of glutamate metabolism and its intercellular trafficking in excitatory synapses from different approaches using transgenic mouse models; such an analysis will contribute to our present understanding of AD.
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Affiliation(s)
| | - Arturo Ortega
- Departamento de Toxicología, Cinvestav- IPN, Mexico City, México
| | - Angelina Rodríguez
- Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Santiago de Querétaro, México.
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3
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Cortese GP, Bartosch AMW, Xiao H, Gribkova Y, Lam TG, Argyrousi EK, Sivakumar S, Cardona C, Teich AF. ZCCHC17 knockdown phenocopies Alzheimer's disease-related loss of synaptic proteins and hyperexcitability. J Neuropathol Exp Neurol 2024; 83:626-635. [PMID: 38630575 PMCID: PMC11187431 DOI: 10.1093/jnen/nlae033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024] Open
Abstract
ZCCHC17 is a master regulator of synaptic gene expression and has recently been shown to play a role in splicing of neuronal mRNA. We previously showed that ZCCHC17 protein declines in Alzheimer's disease (AD) brain tissue before there is significant gliosis and neuronal loss, that ZCCHC17 loss partially replicates observed splicing abnormalities in AD brain tissue, and that maintenance of ZCCHC17 levels is predicted to support cognitive resilience in AD. Here, we assessed the functional consequences of reduced ZCCHC17 expression in primary cortical neuronal cultures using siRNA knockdown. Consistent with its previously identified role in synaptic gene expression, loss of ZCCHC17 led to loss of synaptic protein expression. Patch recording of neurons shows that ZCCHC17 loss significantly disrupted the excitation/inhibition balance of neurotransmission, and favored excitatory-dominant synaptic activity as measured by an increase in spontaneous excitatory post synaptic currents and action potential firing rate, and a decrease in spontaneous inhibitory post synaptic currents. These findings are consistent with the hyperexcitable phenotype seen in AD animal models and in patients. We are the first to assess the functional consequences of ZCCHC17 knockdown in neurons and conclude that ZCCHC17 loss partially phenocopies AD-related loss of synaptic proteins and hyperexcitability.
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Affiliation(s)
- Giuseppe P Cortese
- College of Arts, Sciences, and Education, Program in Biology, Montana State University Northern, Havre, Montana, USA
| | - Anne Marie W Bartosch
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
| | - Harrison Xiao
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
| | - Yelizaveta Gribkova
- Department of Psychiatry, Columbia University Irving Medical Center, New York, New York, USA
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, New York, USA
| | - Tiffany G Lam
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
| | - Elentina K Argyrousi
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
| | - Sharanya Sivakumar
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
| | - Christopher Cardona
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
| | - Andrew F Teich
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, New York, USA
- Department of Neurology, Columbia University Irving Medical Center, New York, New York, USA
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L'esperance OJ, McGhee J, Davidson G, Niraula S, Smith AS, Sosunov A, Yan SS, Subramanian J. Functional connectivity favors aberrant visual network c-Fos expression accompanied by cortical synapse loss in a mouse model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.05.522900. [PMID: 36712054 PMCID: PMC9881957 DOI: 10.1101/2023.01.05.522900] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
While Alzheimer's disease (AD) has been extensively studied with a focus on cognitive networks, sensory network dysfunction has received comparatively less attention despite compelling evidence of its significance in both Alzheimer's disease patients and mouse models. We recently found that neurons in the primary visual cortex of an AD mouse model expressing human amyloid protein precursor with the Swedish and Indiana mutations (hAPP mutations) exhibit aberrant c-Fos expression and altered synaptic structures at a pre-amyloid plaque stage. However, it is unclear whether aberrant c-Fos expression and synaptic pathology vary across the broader visual network and to what extent c-Fos abnormality in the cortex is inherited through functional connectivity. Using both sexes of 4-6-month AD model mice with hAPP mutations (J20[PDGF-APPSw, Ind]), we found that cortical regions of the visual network show aberrant c-Fos expression and impaired experience-dependent modulation while subcortical regions do not. Interestingly, the average network-wide functional connectivity strength of a brain region in wild type (WT) mice significantly predicts its aberrant c-Fos expression, which in turn correlates with impaired experience-dependent modulation in the AD model. Using in vivo two-photon and ex vivo imaging of presynaptic termini, we observed a subtle yet selective weakening of excitatory cortical synapses in the visual cortex. Intriguingly, the change in the size distribution of cortical boutons in the AD model is downscaled relative to those in WT mice, suggesting that synaptic weakening may reflect an adaptation to aberrant activity. Our observations suggest that cellular and synaptic abnormalities in the AD model represent a maladaptive transformation of the baseline physiological state seen in WT conditions rather than entirely novel and unrelated manifestations.
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Liang J, Wang Y, Liu B, Dong X, Cai W, Zhang N, Zhang H. Deciphering the intricate linkage between the gut microbiota and Alzheimer's disease: Elucidating mechanistic pathways promising therapeutic strategies. CNS Neurosci Ther 2024; 30:e14704. [PMID: 38584341 PMCID: PMC10999574 DOI: 10.1111/cns.14704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/15/2023] [Accepted: 03/25/2024] [Indexed: 04/09/2024] Open
Abstract
BACKGROUND The gut microbiome is composed of various microorganisms such as bacteria, fungi, and protozoa, and constitutes an important part of the human gut. Its composition is closely related to human health and disease. Alzheimer's disease (AD) is a neurodegenerative disease whose underlying mechanism has not been fully elucidated. Recent research has shown that there are significant differences in the gut microbiota between AD patients and healthy individuals. Changes in the composition of gut microbiota may lead to the development of harmful factors associated with AD. In addition, the gut microbiota may play a role in the development and progression of AD through the gut-brain axis. However, the exact nature of this relationship has not been fully understood. AIMS This review will elucidate the types and functions of gut microbiota and their relationship with AD and explore in depth the potential mechanisms of gut microbiota in the occurrence of AD and the prospects for treatment strategies. METHODS Reviewed literature from PubMed and Web of Science using key terminologies related to AD and the gut microbiome. RESULTS Research indicates that the gut microbiota can directly or indirectly influence the occurrence and progression of AD through metabolites, endotoxins, and the vagus nerve. DISCUSSION This review discusses the future challenges and research directions regarding the gut microbiota in AD. CONCLUSION While many unresolved issues remain regarding the gut microbiota and AD, the feasibility and immense potential of treating AD by modulating the gut microbiota are evident.
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Affiliation(s)
- Junyi Liang
- Heilongjiang University of Traditional Chinese MedicineHarbinHeilongjiang ProvinceChina
| | - Yueyang Wang
- Heilongjiang University of Traditional Chinese MedicineHarbinHeilongjiang ProvinceChina
| | - Bin Liu
- Heilongjiang University of Traditional Chinese MedicineHarbinHeilongjiang ProvinceChina
| | - Xiaohong Dong
- Jiamusi CollegeHeilongjiang University of Traditional Chinese MedicineJiamusiHeilongjiang ProvinceChina
| | - Wenhui Cai
- Heilongjiang University of Traditional Chinese MedicineHarbinHeilongjiang ProvinceChina
| | - Ning Zhang
- Heilongjiang University of Traditional Chinese MedicineHarbinHeilongjiang ProvinceChina
| | - Hong Zhang
- Heilongjiang Jiamusi Central HospitalJiamusiHeilongjiang ProvinceChina
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6
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Chen Y, Li Z, Ge X, Lv H, Geng Z. Identification of novel hub genes for Alzheimer's disease associated with the hippocampus using WGCNA and differential gene analysis. Front Neurosci 2024; 18:1359631. [PMID: 38516314 PMCID: PMC10954837 DOI: 10.3389/fnins.2024.1359631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/28/2024] [Indexed: 03/23/2024] Open
Abstract
Background Alzheimer's disease (AD) is a common, refractory, progressive neurodegenerative disorder in which cognitive and memory deficits are highly correlated with abnormalities in hippocampal brain regions. There is still a lack of hippocampus-related markers for AD diagnosis and prevention. Methods Differently expressed genes were identified in the gene expression profile GSE293789 in the hippocampal brain region. Enrichment analyses GO, KEGG, and GSEA were used to identify biological pathways involved in the DEGs and AD-related group. WGCNA was used to identify the gene modules that are highly associated with AD in the samples. The intersecting genes of the genes in DEGs and modules were extracted and the top ten ranked hub genes were identified. Finally GES48350 was used as a validation cohort to predict the diagnostic efficacy of hub genes. Results From GSE293789, 225 DEGs were identified, which were mainly associated with calcium response, glutamatergic synapses, and calcium-dependent phospholipid-binding response. WGCNA analysis yielded dark green and bright yellow modular genes as the most relevant to AD. From these two modules, 176 genes were extracted, which were taken to be intersected with DEGs, yielding 51 intersecting genes. Then 10 hub genes were identified in them: HSPA1B, HSPB1, HSPA1A, DNAJB1, HSPB8, ANXA2, ANXA1, SOX9, YAP1, and AHNAK. Validation of these genes was found to have excellent diagnostic performance. Conclusion Ten AD-related hub genes in the hippocampus were identified, contributing to further understanding of AD development in the hippocampus and development of targets for therapeutic prevention.
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Affiliation(s)
- Yang Chen
- Graduate School, Hebei Medical University, Shijiazhuang, China
| | - Zhaoxiang Li
- Department of Immunology and Pathogenic Biology, Yanbian University Medical College, Yanji, China
| | - Xin Ge
- Science and Education Section, Baoding First Central Hospital, Baoding, China
| | - Huandi Lv
- Department of Medical Imaging, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Zuojun Geng
- Department of Medical Imaging, The Second Hospital of Hebei Medical University, Shijiazhuang, China
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7
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Li Y, Yang P, Meng R, Xu S, Zhou L, Qian K, Wang P, Cheng Y, Sheng D, Xu M, Wang T, Wu J, Cao J, Zhang Q. Multidimensional autophagy nano-regulator boosts Alzheimer's disease treatment by improving both extra/intraneuronal homeostasis. Acta Pharm Sin B 2024; 14:1380-1399. [PMID: 38486986 PMCID: PMC10935063 DOI: 10.1016/j.apsb.2023.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 03/17/2024] Open
Abstract
Intraneuronal dysproteostasis and extraneuronal microenvironmental abnormalities in Alzheimer's disease (AD) collectively culminate in neuronal deterioration. In the context of AD, autophagy dysfunction, a multi-link obstacle involving autophagy downregulation and lysosome defects in neurons/microglia is highly implicated in intra/extraneuronal pathological processes. Therefore, multidimensional autophagy regulation strategies co-manipulating "autophagy induction" and "lysosome degradation" in dual targets (neuron and microglia) are more reliable for AD treatment. Accordingly, we designed an RP-1 peptide-modified reactive oxygen species (ROS)-responsive micelles (RT-NM) loading rapamycin or gypenoside XVII. Guided by RP-1 peptide, the ligand of receptor for advanced glycation end products (RAGE), RT-NM efficiently targeted neurons and microglia in AD-affected region. This nano-combination therapy activated the whole autophagy-lysosome pathway by autophagy induction (rapamycin) and lysosome improvement (gypenoside XVII), thus enhancing autophagic degradation of neurotoxic aggregates and inflammasomes, and promoting Aβ phagocytosis. Resultantly, it decreased aberrant protein burden, alleviated neuroinflammation, and eventually ameliorated memory defects in 3 × Tg-AD transgenic mice. Our research developed a multidimensional autophagy nano-regulator to boost the efficacy of autophagy-centered AD therapy.
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Affiliation(s)
| | | | | | - Shuting Xu
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Lingling Zhou
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Kang Qian
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Pengzhen Wang
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Yunlong Cheng
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Dongyu Sheng
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Minjun Xu
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Tianying Wang
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Jing Wu
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Jinxu Cao
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
| | - Qizhi Zhang
- Key Laboratory of Smart Drug Delivery, Ministry of Education, School of Pharmacy, Fudan University, Shanghai 201203, China
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8
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Soares C, Da Ros LU, Machado LS, Rocha A, Lazzarotto G, Carello-Collar G, De Bastiani MA, Ferrari-Souza JP, Lussier FZ, Souza DO, Rosa-Neto P, Pascoal TA, Bellaver B, Zimmer ER. The glutamatergic system in Alzheimer's disease: a systematic review with meta-analysis. Mol Psychiatry 2024:10.1038/s41380-024-02473-0. [PMID: 38366114 DOI: 10.1038/s41380-024-02473-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/23/2024] [Accepted: 01/31/2024] [Indexed: 02/18/2024]
Abstract
Glutamatergic neurotransmission system dysregulation may play an important role in the pathophysiology of Alzheimer's disease (AD). However, reported results on glutamatergic components across brain regions are contradictory. Here, we conducted a systematic review with meta-analysis to examine whether there are consistent glutamatergic abnormalities in the human AD brain. We searched PubMed and Web of Science (database origin-October 2023) reports evaluating glutamate, glutamine, glutaminase, glutamine synthetase, glutamate reuptake, aspartate, excitatory amino acid transporters, vesicular glutamate transporters, glycine, D-serine, metabotropic and ionotropic glutamate receptors in the AD human brain (PROSPERO #CDRD42022299518). The studies were synthesized by outcome and brain region. We included cortical regions, the whole brain (cortical and subcortical regions combined), the entorhinal cortex and the hippocampus. Pooled effect sizes were determined with standardized mean differences (SMD), random effects adjusted by false discovery rate, and heterogeneity was examined by I2 statistics. The search retrieved 6 936 articles, 63 meeting the inclusion criteria (N = 709CN/786AD; mean age 75/79). We showed that the brain of AD individuals presents decreased glutamate (SMD = -0.82; I2 = 74.54%; P < 0.001) and aspartate levels (SMD = -0.64; I2 = 89.71%; P = 0.006), and reuptake (SMD = -0.75; I2 = 83.04%; P < 0.001. We also found reduced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPAR)-GluA2/3 levels (SMD = -0.63; I2 = 95.55%; P = 0.046), hypofunctional N-methyl-D-aspartate receptor (NMDAR) (SMD = -0.60; I2 = 91.47%; P < 0.001) and selective reduction of NMDAR-GluN2B subunit levels (SMD = -1.07; I2 = 41.81%; P < 0.001). Regional differences include lower glutamate levels in cortical areas and aspartate levels in cortical areas and in the hippocampus, reduced glutamate reuptake, reduced AMPAR-GluA2/3 in the entorhinal cortex, hypofunction of NMDAR in cortical areas, and a decrease in NMDAR-GluN2B subunit levels in the entorhinal cortex and hippocampus. Other parameters studied were not altered. Our findings show depletion of the glutamatergic system and emphasize the importance of understanding glutamate-mediated neurotoxicity in AD. This study has implications for the development of therapies and biomarkers in AD.
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Affiliation(s)
- Carolina Soares
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lucas Uglione Da Ros
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Luiza Santos Machado
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Andreia Rocha
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Gabriela Lazzarotto
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Giovanna Carello-Collar
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Marco A De Bastiani
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, UFRGS, Porto Alegre, Brazil
| | - João Pedro Ferrari-Souza
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Firoza Z Lussier
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Diogo O Souza
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Biochemistry, UFRGS, Porto Alegre, Brazil
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, McGill University, Montreal, QC, Canada
- Douglas Research Institute, Le Centre Intégré Universitaire de Santé et de Services Sociaux de l'Ouest-de-l'Île-de-Montréal, McGill University, Montreal, QC, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | - Tharick A Pascoal
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bruna Bellaver
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Eduardo R Zimmer
- Graduate Program in Biological Sciences: Biochemistry, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, UFRGS, Porto Alegre, Brazil.
- Department of Biochemistry, UFRGS, Porto Alegre, Brazil.
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.
- Brain Institute of Rio Grande do Sul - Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
- Department of Pharmacology, UFRGS, Porto Alegre, Brazil.
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9
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Niraula S, Yan SS, Subramanian J. Amyloid Pathology Impairs Experience-Dependent Inhibitory Synaptic Plasticity. J Neurosci 2024; 44:e0702232023. [PMID: 38050105 PMCID: PMC10860629 DOI: 10.1523/jneurosci.0702-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 11/09/2023] [Accepted: 11/14/2023] [Indexed: 12/06/2023] Open
Abstract
Alzheimer's disease patients and mouse models exhibit aberrant neuronal activity and altered excitatory-to-inhibitory synaptic ratio. Using multicolor two-photon microscopy, we test how amyloid pathology alters the structural dynamics of excitatory and inhibitory synapses and their adaptation to altered visual experience in vivo in the visual cortex. We show that the baseline dynamics of mature excitatory synapses and their adaptation to visual deprivation are not altered in amyloidosis. Likewise, the baseline dynamics of inhibitory synapses are not affected. In contrast, visual deprivation fails to induce inhibitory synapse loss in amyloidosis, a phenomenon observed in nonpathological conditions. Intriguingly, inhibitory synapse loss associated with visual deprivation in nonpathological mice is accompanied by subtle broadening of spontaneous but not visually evoked calcium transients. However, such broadening does not manifest in the context of amyloidosis. We also show that excitatory and inhibitory synapse loss is locally clustered under the nonpathological state. In contrast, a fraction of synapse loss is not locally clustered in amyloidosis, indicating an impairment in inhibitory synapse adaptation to changes in excitatory synaptic activity.
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Affiliation(s)
- Suraj Niraula
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, Kansas 66045
| | - Shirley ShiDu Yan
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, Kansas 66045
- Department of Surgery, Vagelos College of Physicians and Surgeons of Columbia University, New York, New York 10032
| | - Jaichandar Subramanian
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, Kansas 66045
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10
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Nystuen KL, McNamee SM, Akula M, Holton KM, DeAngelis MM, Haider NB. Alzheimer's Disease: Models and Molecular Mechanisms Informing Disease and Treatments. Bioengineering (Basel) 2024; 11:45. [PMID: 38247923 PMCID: PMC10813760 DOI: 10.3390/bioengineering11010045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/15/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024] Open
Abstract
Alzheimer's Disease (AD) is a complex neurodegenerative disease resulting in progressive loss of memory, language and motor abilities caused by cortical and hippocampal degeneration. This review captures the landscape of understanding of AD pathology, diagnostics, and current therapies. Two major mechanisms direct AD pathology: (1) accumulation of amyloid β (Aβ) plaque and (2) tau-derived neurofibrillary tangles (NFT). The most common variants in the Aβ pathway in APP, PSEN1, and PSEN2 are largely responsible for early-onset AD (EOAD), while MAPT, APOE, TREM2 and ABCA7 have a modifying effect on late-onset AD (LOAD). More recent studies implicate chaperone proteins and Aβ degrading proteins in AD. Several tests, such as cognitive function, brain imaging, and cerebral spinal fluid (CSF) and blood tests, are used for AD diagnosis. Additionally, several biomarkers seem to have a unique AD specific combination of expression and could potentially be used in improved, less invasive diagnostics. In addition to genetic perturbations, environmental influences, such as altered gut microbiome signatures, affect AD. Effective AD treatments have been challenging to develop. Currently, there are several FDA approved drugs (cholinesterase inhibitors, Aß-targeting antibodies and an NMDA antagonist) that could mitigate AD rate of decline and symptoms of distress.
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Affiliation(s)
- Kaden L. Nystuen
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Shannon M. McNamee
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA
| | - Monica Akula
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA
| | - Kristina M. Holton
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
- Harvard Stem Cell Institute, Cambridge, MA 02138, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Margaret M. DeAngelis
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | - Neena B. Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
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11
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Niraula S, Yan SS, Subramanian J. Amyloid pathology impairs experience-dependent inhibitory synaptic plasticity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.04.539450. [PMID: 37205469 PMCID: PMC10187277 DOI: 10.1101/2023.05.04.539450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Alzheimer's disease patients and mouse models exhibit aberrant neuronal activity and altered excitatory-to-inhibitory synaptic ratio. Using multicolor two-photon microscopy, we test how amyloid pathology alters the structural dynamics of excitatory and inhibitory synapses and their adaptation to altered visual experience in vivo in the visual cortex. We show that the baseline dynamics of mature excitatory synapses and their adaptation to visual deprivation are not altered in amyloidosis. Likewise, the baseline dynamics of inhibitory synapses are not affected. In contrast, visual deprivation fails to induce inhibitory synapse loss in amyloidosis, a phenomenon observed in nonpathological conditions. Intriguingly, inhibitory synapse loss associated with visual deprivation in nonpathological mice is accompanied by the broadening of spontaneous but not visually evoked calcium transients. However, such broadening does not manifest in the context of amyloidosis. We also show that excitatory and inhibitory synapse loss is locally clustered under the nonpathological state. In contrast, a fraction of synapse loss is not locally clustered in amyloidosis, indicating an impairment in inhibitory synapse adaptation to changes in excitatory synaptic activity.
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Affiliation(s)
- Suraj Niraula
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Shirley ShiDu Yan
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
- Department of Surgery, Vagelos College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Jaichandar Subramanian
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
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12
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Liang J, Liu B, Dong X, Wang Y, Cai W, Zhang N, Zhang H. Decoding the role of gut microbiota in Alzheimer's pathogenesis and envisioning future therapeutic avenues. Front Neurosci 2023; 17:1242254. [PMID: 37790586 PMCID: PMC10544353 DOI: 10.3389/fnins.2023.1242254] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 09/04/2023] [Indexed: 10/05/2023] Open
Abstract
Alzheimer's disease (AD) emerges as a perturbing neurodegenerative malady, with a profound comprehension of its underlying pathogenic mechanisms continuing to evade our intellectual grasp. Within the intricate tapestry of human health and affliction, the enteric microbial consortium, ensconced within the milieu of the human gastrointestinal tract, assumes a role of cardinal significance. Recent epochs have borne witness to investigations that posit marked divergences in the composition of the gut microbiota between individuals grappling with AD and those favored by robust health. The composite vicissitudes in the configuration of the enteric microbial assembly are posited to choreograph a participatory role in the inception and progression of AD, facilitated by the intricate conduit acknowledged as the gut-brain axis. Notwithstanding, the precise nature of this interlaced relationship remains enshrouded within the recesses of obscurity, poised for an exhaustive revelation. This review embarks upon the endeavor to focalize meticulously upon the mechanistic sway exerted by the enteric microbiota upon AD, plunging profoundly into the execution of interventions that govern the milieu of enteric microorganisms. In doing so, it bestows relevance upon the therapeutic stratagems that form the bedrock of AD's management, all whilst casting a prospective gaze into the horizon of medical advancements.
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Affiliation(s)
- Junyi Liang
- Heilongjiang University of Traditional Chinese Medicine, Harbin, Heilongjiang, China
| | - Bin Liu
- Heilongjiang University of Traditional Chinese Medicine, Harbin, Heilongjiang, China
| | - Xiaohong Dong
- Heilongjiang University of Traditional Chinese Medicine, Harbin, Heilongjiang, China
| | - Yueyang Wang
- Heilongjiang University of Traditional Chinese Medicine, Harbin, Heilongjiang, China
| | - Wenhui Cai
- Heilongjiang University of Traditional Chinese Medicine, Harbin, Heilongjiang, China
| | - Ning Zhang
- Heilongjiang University of Traditional Chinese Medicine, Harbin, Heilongjiang, China
| | - Hong Zhang
- Heilongjiang Jiamusi Central Hospital, Jiamusi, Heilongjiang, China
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13
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Melo de Farias AR, Pelletier A, Iohan LCC, Saha O, Bonnefond A, Amouyel P, Delahaye F, Lambert JC, Costa MR. Amyloid-Beta Peptides Trigger Premature Functional and Gene Expression Alterations in Human-Induced Neurons. Biomedicines 2023; 11:2564. [PMID: 37761004 PMCID: PMC10526858 DOI: 10.3390/biomedicines11092564] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
Alzheimer's disease (AD) is the most prevalent cause of dementia in the elderly, characterized by the presence of amyloid-beta (Aβ) plaques, neurofibrillary tangles, neuroinflammation, synapse loss and neurodegeneration in the brain. The amyloid cascade hypothesis postulates that deposition of Aβ peptides is the causative agent of AD pathology, but we still lack comprehensive understanding of the molecular mechanisms connecting Aβ peptides to neuronal dysfunctions in AD. In this work, we investigate the early effects of Aβ peptide accumulation on the functional properties and gene expression profiles of human-induced neurons (hiNs). We show that hiNs acutely exposed to low concentrations of both cell-secreted Aβ peptides or synthetic Aβ1-42 exhibit alterations in the frequency of calcium transients suggestive of increased neuronal excitability. Using single-cell RNA sequencing, we also show that cell-secreted Aβ up-regulates the expression of several synapse-related genes and down-regulates the expression of genes associated with metabolic stress mainly in glutamatergic neurons and, to a lesser degree, in GABAergic neurons and astrocytes. These neuronal alterations correlate with activation of the SEMA5, EPHA and NECTIN signaling pathways, which are important regulators of synaptic plasticity. Altogether, our findings indicate that slight elevations in Aβ concentrations are sufficient to elicit transcriptional changes in human neurons, which can contribute to early alterations in neural network activity.
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Affiliation(s)
- Ana Raquel Melo de Farias
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de Risque et Déterminants Moléculaires des Maladies Liées au Vieillissement, DISTALZ, 1 rue du Professeur Calmette, 59019 Lille, France; (A.R.M.d.F.); (O.S.); (P.A.); (J.-C.L.)
- Brain Institute, Federal University of Rio Grande do Norte, Campus Universitário Lagoa Nova, Av. Senador Salgado Filho, 3000, Natal 59078-970, Brazil
| | - Alexandre Pelletier
- Université de Lille, Inserm, CNRS, CHU Lille, Institut Pasteur de Lille, U1283-UMR 8199 EGID, Pôle Recherche, 1 Place de Verdun, CEDEX, 59045 Lille, France; (A.P.); (A.B.); (F.D.)
| | - Lukas Cruz Carvalho Iohan
- Bioinformatics Multidisciplinary Environment, Federal University of Rio Grande do Norte, Natal 59078-970, Brazil;
| | - Orthis Saha
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de Risque et Déterminants Moléculaires des Maladies Liées au Vieillissement, DISTALZ, 1 rue du Professeur Calmette, 59019 Lille, France; (A.R.M.d.F.); (O.S.); (P.A.); (J.-C.L.)
| | - Amélie Bonnefond
- Université de Lille, Inserm, CNRS, CHU Lille, Institut Pasteur de Lille, U1283-UMR 8199 EGID, Pôle Recherche, 1 Place de Verdun, CEDEX, 59045 Lille, France; (A.P.); (A.B.); (F.D.)
| | - Philippe Amouyel
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de Risque et Déterminants Moléculaires des Maladies Liées au Vieillissement, DISTALZ, 1 rue du Professeur Calmette, 59019 Lille, France; (A.R.M.d.F.); (O.S.); (P.A.); (J.-C.L.)
| | - Fabien Delahaye
- Université de Lille, Inserm, CNRS, CHU Lille, Institut Pasteur de Lille, U1283-UMR 8199 EGID, Pôle Recherche, 1 Place de Verdun, CEDEX, 59045 Lille, France; (A.P.); (A.B.); (F.D.)
| | - Jean-Charles Lambert
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de Risque et Déterminants Moléculaires des Maladies Liées au Vieillissement, DISTALZ, 1 rue du Professeur Calmette, 59019 Lille, France; (A.R.M.d.F.); (O.S.); (P.A.); (J.-C.L.)
| | - Marcos R. Costa
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE Facteurs de Risque et Déterminants Moléculaires des Maladies Liées au Vieillissement, DISTALZ, 1 rue du Professeur Calmette, 59019 Lille, France; (A.R.M.d.F.); (O.S.); (P.A.); (J.-C.L.)
- Brain Institute, Federal University of Rio Grande do Norte, Campus Universitário Lagoa Nova, Av. Senador Salgado Filho, 3000, Natal 59078-970, Brazil
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14
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Bakonyi P, Kolonics A, Aczel D, Zhou L, Mozaffaritabar S, Molnár K, László L, Kutasi B, Tanisawa K, Park J, Gu Y, Pinho RA, Radak Z. Voluntary exercise does not increase gastrointestinal motility but increases spatial memory, intestinal eNOS, Akt levels, and Bifidobacteria abundance in the microbiome. Front Physiol 2023; 14:1173636. [PMID: 37664431 PMCID: PMC10468588 DOI: 10.3389/fphys.2023.1173636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 07/03/2023] [Indexed: 09/05/2023] Open
Abstract
The interaction between the gut and brain is a great puzzle since it is mediated by very complex mechanisms. Therefore, the possible interactions of the brain-exercise-intestine-microbiome axis were investigated in a control (C, N = 6) and voluntarily exercised (VE, N = 8) middle-aged rats. The endurance capacity was assessed by VO2max on the treadmill, spatial memory by the Morris maze test, gastrointestinal motility by EMG, the microbiome by 16S RNA gene amplicon sequencing, caveolae by electron microscopy, and biochemical assays were used to measure protein levels and production of reactive oxygen species (ROS). Eight weeks of voluntary running increased VO2max, and spatial memory was assessed by the Morris maze test but did not significantly change the motility of the gastrointestinal tract or production of ROS in the intestine. The protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS) protein levels significantly increased in the intestine, while peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), mitochondrial transcription factor A (TFAM), nuclear respiratory factor 1 (NFR1), SIRT1, SIRT3, nicotinamide phosphoribosyl transferase (NAMPT), and nuclear factor κB (NF-κB) did not change. On the other hand, voluntary exercise increased the number of caveolae in the smooth muscles of the intestine and relative abundance of Bifidobacteria in the microbiome, which correlated with the Akt levels in the intestine. Voluntary exercise has systemic effects and the relationship between intestinal Akt and the microbiome of the gastrointestinal tract could be an important adaptive response.
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Affiliation(s)
- Peter Bakonyi
- Research Institute of Sport Science, Hungarian University of Sport Science, Budapest, Hungary
| | - Attila Kolonics
- Research Institute of Sport Science, Hungarian University of Sport Science, Budapest, Hungary
| | - Dora Aczel
- Research Institute of Sport Science, Hungarian University of Sport Science, Budapest, Hungary
| | - Lei Zhou
- Research Institute of Sport Science, Hungarian University of Sport Science, Budapest, Hungary
| | - Soroosh Mozaffaritabar
- Research Institute of Sport Science, Hungarian University of Sport Science, Budapest, Hungary
| | - Kinga Molnár
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University of Sciences, Budapest, Hungary
| | - Lajos László
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University of Sciences, Budapest, Hungary
| | - Balazs Kutasi
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
| | - Kumpei Tanisawa
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan
| | - Jonguk Park
- Artificial Intelligence Center for Health and Biomedical Research, Osaka, Japan
| | - Yaodong Gu
- Faculty of Sports Science, Ningbo University, Ningbo, China
| | - Ricardo A. Pinho
- Laboratory of Exercise Biochemistry in Health, Graduate Program in Health Sciences, School of Medicine, Pontifícia Universidade Católica Do Paraná, Curitiba, Brazil
| | - Zsolt Radak
- Research Institute of Sport Science, Hungarian University of Sport Science, Budapest, Hungary
- Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan
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15
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Huffels CFM, Middeldorp J, Hol EM. Aß Pathology and Neuron-Glia Interactions: A Synaptocentric View. Neurochem Res 2023; 48:1026-1046. [PMID: 35976488 PMCID: PMC10030451 DOI: 10.1007/s11064-022-03699-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 06/30/2022] [Accepted: 07/15/2022] [Indexed: 10/15/2022]
Abstract
Alzheimer's disease (AD) causes the majority of dementia cases worldwide. Early pathological hallmarks include the accumulation of amyloid-ß (Aß) and activation of both astrocytes and microglia. Neurons form the building blocks of the central nervous system, and astrocytes and microglia provide essential input for its healthy functioning. Their function integrates at the level of the synapse, which is therefore sometimes referred to as the "quad-partite synapse". Increasing evidence puts AD forward as a disease of the synapse, where pre- and postsynaptic processes, as well as astrocyte and microglia functioning progressively deteriorate. Here, we aim to review the current knowledge on how Aß accumulation functionally affects the individual components of the quad-partite synapse. We highlight a selection of processes that are essential to the healthy functioning of the neuronal synapse, including presynaptic neurotransmitter release and postsynaptic receptor functioning. We further discuss how Aß affects the astrocyte's capacity to recycle neurotransmitters, release gliotransmitters, and maintain ion homeostasis. We additionally review literature on how Aß changes the immunoprotective function of microglia during AD progression and conclude by summarizing our main findings and highlighting the challenges in current studies, as well as the need for further research.
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Affiliation(s)
- Christiaan F M Huffels
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Jinte Middeldorp
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
- Department of Neurobiology & Aging, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands.
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16
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Melgosa-Ecenarro L, Doostdar N, Radulescu CI, Jackson JS, Barnes SJ. Pinpointing the locus of GABAergic vulnerability in Alzheimer's disease. Semin Cell Dev Biol 2023; 139:35-54. [PMID: 35963663 DOI: 10.1016/j.semcdb.2022.06.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 06/30/2022] [Accepted: 06/30/2022] [Indexed: 12/31/2022]
Abstract
The early stages of Alzheimer's disease (AD) have been linked to microcircuit dysfunction and pathophysiological neuronal firing in several brain regions. Inhibitory GABAergic microcircuitry is a critical feature of stable neural-circuit function in the healthy brain, and its dysregulation has therefore been proposed as contributing to AD-related pathophysiology. However, exactly how the critical balance between excitatory and inhibitory microcircuitry is modified by AD pathogenesis remains unclear. Here, we set the current evidence implicating dysfunctional GABAergic microcircuitry as a driver of early AD pathophysiology in a simple conceptual framework. Our framework is based on a generalised reductionist model of firing-rate control by local feedback inhibition. We use this framework to consider multiple loci that may be vulnerable to disruption by AD pathogenesis. We first start with evidence investigating how AD-related processes may impact the gross number of inhibitory neurons in the network. We then move to discuss how pathology may impact intrinsic cellular properties and firing thresholds of GABAergic neurons. Finally, we cover how AD-related pathogenesis may disrupt synaptic connectivity between excitatory and inhibitory neurons. We use the feedback inhibition framework to discuss and organise the available evidence from both preclinical rodent work and human studies in AD patients and conclude by identifying key questions and understudied areas for future investigation.
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Affiliation(s)
- Leire Melgosa-Ecenarro
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Nazanin Doostdar
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Carola I Radulescu
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Johanna S Jackson
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK
| | - Samuel J Barnes
- UK Dementia Research Institute, Department of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London W12 0NN, UK.
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17
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Tousley AR, Yeh PWL, Yeh HH. Precocious emergence of cognitive and synaptic dysfunction in 3xTg-AD mice exposed prenatally to ethanol. Alcohol 2023; 107:56-72. [PMID: 36038084 PMCID: PMC10183974 DOI: 10.1016/j.alcohol.2022.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/01/2022] [Accepted: 08/09/2022] [Indexed: 12/27/2022]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia, affecting approximately 50 million people worldwide. Early life risk factors for AD, including prenatal exposures, remain underexplored. Exposure of the fetus to alcohol (ethanol) is not uncommon during pregnancy, and may result in physical, behavioral, and cognitive changes that are first detected during childhood but result in lifelong challenges. Whether or not prenatal ethanol exposure may contribute to Alzheimer's disease risk is not yet known. Here we exposed a mouse model of Alzheimer's disease (3xTg-AD), bearing three dementia-associated transgenes, presenilin1 (PS1M146V), human amyloid precursor protein (APPSwe), and human tau (TauP301S), to ethanol on gestational days 13.5-16.5 using an established binge-type maternal ethanol exposure paradigm. We sought to investigate whether prenatal ethanol exposure resulted in a precocious onset or increased severity of AD progression, or both. We found that a brief binge-type gestational exposure to ethanol during a period of peak neuronal migration to the developing cortex resulted in an earlier onset of spatial memory deficits and behavioral inflexibility in the progeny, as assessed by performance on the modified Barnes maze task. The observed cognitive changes coincided with alterations to both GABAergic and glutamatergic synaptic transmission in layer V/VI neurons, diminished GABAergic interneurons, and increased β-amyloid accumulation in the medial prefrontal cortex. These findings provide the first preclinical evidence for prenatal ethanol exposure as a potential factor for modifying the onset of AD-like behavioral dysfunction and set the groundwork for more comprehensive investigations into the underpinnings of AD-like cognitive changes in individuals with fetal alcohol spectrum disorders.
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Affiliation(s)
- Adelaide R Tousley
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States; MD-PhD Program, Geisel School of Medicine at Dartmouth; Integrative Neuroscience at Dartmouth Graduate Program, Hanover, NH, United States
| | - Pamela W L Yeh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States
| | - Hermes H Yeh
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, United States.
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18
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Mathew A, Balaji E V, Pai SRK, Kishore A, Pai V, Pemmireddy R, K S C. Current Drug Targets in Alzheimer's Associated Memory Impairment: A Comprehensive Review. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2023; 22:255-275. [PMID: 35366787 DOI: 10.2174/1871527321666220401124719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 12/17/2021] [Accepted: 01/19/2022] [Indexed: 12/16/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent form of dementia among geriatrics. It is a progressive, degenerative neurologic disorder that causes memory and cognition loss. The accumulation of amyloid fibrils and neurofibrillary tangles in the brain of AD patients is a distinguishing feature of the disease. Therefore, most of the current therapeutic goals are targeting inhibition of beta-amyloid synthesis and aggregation as well as tau phosphorylation and aggregation. There is also a loss of the cholinergic neurons in the basal forebrain, and first-generation therapeutic agents were primarily focused on compensating for this loss of neurons. However, cholinesterase inhibitors can only alleviate cognitive symptoms of AD and cannot reduce the progression of the disease. Understanding the molecular and cellular changes associated with AD pathology has advanced significantly in recent decades. The etiology of AD is complex, with a substantial portion of sporadic AD emerging from unknown reasons and a lesser proportion of early-onset familial AD (FAD) caused by a mutation in several genes, such as the amyloid precursor protein (APP), presenilin 1 (PS1), and presenilin 2 (PS2) genes. Hence, efforts are being made to discover novel strategies for these targets for AD therapy. A new generation of AChE and BChE inhibitors is currently being explored and evaluated in human clinical trials for AD symptomatic treatment. Other approaches for slowing the progression of AD include serotonergic modulation, H3 receptor antagonism, phosphodiesterase, COX-2, and MAO-B inhibition. The present review provides an insight into the possible therapeutic strategies and their molecular mechanisms, enlightening the perception of classical and future treatment approaches.
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Affiliation(s)
- Anna Mathew
- Department of Pharmacognosy, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Vignesh Balaji E
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Sreedhara Ranganath K Pai
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Anoop Kishore
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Vasudev Pai
- Department of Pharmacognosy, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Ramadevi Pemmireddy
- Department of Pharmacognosy, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Chandrashekar K S
- Department of Pharmacognosy, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
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19
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van den Berg M, Adhikari MH, Verschuuren M, Pintelon I, Vasilkovska T, Van Audekerke J, Missault S, Heymans L, Ponsaerts P, De Vos WH, Van der Linden A, Keliris GA, Verhoye M. Altered basal forebrain function during whole-brain network activity at pre- and early-plaque stages of Alzheimer's disease in TgF344-AD rats. Alzheimers Res Ther 2022; 14:148. [PMID: 36217211 PMCID: PMC9549630 DOI: 10.1186/s13195-022-01089-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/22/2022] [Indexed: 11/10/2022]
Abstract
BACKGROUND Imbalanced synaptic transmission appears to be an early driver in Alzheimer's disease (AD) leading to brain network alterations. Early detection of altered synaptic transmission and insight into mechanisms causing early synaptic alterations would be valuable treatment strategies. This study aimed to investigate how whole-brain networks are influenced at pre- and early-plague stages of AD and if these manifestations are associated with concomitant cellular and synaptic deficits. METHODS: To this end, we used an established AD rat model (TgF344-AD) and employed resting state functional MRI and quasi-periodic pattern (QPP) analysis, a method to detect recurrent spatiotemporal motifs of brain activity, in parallel with state-of-the-art immunohistochemistry in selected brain regions. RESULTS At the pre-plaque stage, QPPs in TgF344-AD rats showed decreased activity of the basal forebrain (BFB) and the default mode-like network. Histological analyses revealed increased astrocyte abundance restricted to the BFB, in the absence of amyloid plaques, tauopathy, and alterations in a number of cholinergic, gaba-ergic, and glutamatergic synapses. During the early-plaque stage, when mild amyloid-beta (Aβ) accumulation was observed in the cortex and hippocampus, QPPs in the TgF344-AD rats normalized suggesting the activation of compensatory mechanisms during this early disease progression period. Interestingly, astrogliosis observed in the BFB at the pre-plaque stage was absent at the early-plaque stage. Moreover, altered excitatory/inhibitory balance was observed in cortical regions belonging to the default mode-like network. In wild-type rats, at both time points, peak activity in the BFB preceded peak activity in other brain regions-indicating its modulatory role during QPPs. However, this pattern was eliminated in TgF344-AD suggesting that alterations in BFB-directed neuromodulation have a pronounced impact in network function in AD. CONCLUSIONS This study demonstrates the value of rsfMRI and advanced network analysis methods to detect early alterations in BFB function in AD, which could aid early diagnosis and intervention in AD. Restoring the global synaptic transmission, possibly by modulating astrogliosis in the BFB, might be a promising therapeutic strategy to restore brain network function and delay the onset of symptoms in AD.
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Affiliation(s)
- Monica van den Berg
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Mohit H. Adhikari
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Marlies Verschuuren
- grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,Antwerp Centre for Advanced Microscopy, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Isabel Pintelon
- grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,Antwerp Centre for Advanced Microscopy, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Tamara Vasilkovska
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Johan Van Audekerke
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Stephan Missault
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Loran Heymans
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Peter Ponsaerts
- grid.5284.b0000 0001 0790 3681Laboratory of Experimental Hematology, Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Winnok H. De Vos
- grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,Antwerp Centre for Advanced Microscopy, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Annemie Van der Linden
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Georgios A. Keliris
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.511960.aInstitute of Computer Science, Foundation for Research & Technology - Hellas, Heraklion, Crete, Greece
| | - Marleen Verhoye
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
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20
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Implications of Microorganisms in Alzheimer's Disease. Curr Issues Mol Biol 2022; 44:4584-4615. [PMID: 36286029 PMCID: PMC9600878 DOI: 10.3390/cimb44100314] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 09/23/2022] [Accepted: 09/28/2022] [Indexed: 11/20/2022] Open
Abstract
Alzheimer’s disease (AD) is a deadly brain degenerative disorder that leads to brain shrinkage and dementia. AD is manifested with hyperphosphorylated tau protein levels and amyloid beta (Aβ) peptide buildup in the hippocampus and cortex regions of the brain. The nervous tissue of AD patients also contains fungal proteins and DNA which are linked to bacterial infections, suggesting that polymicrobial infections also occur in the brains of those with AD. Both immunohistochemistry and next-generation sequencing (NGS) techniques were employed to assess fungal and bacterial infections in the brain tissue of AD patients and non-AD controls, with the most prevalent fungus genera detected in AD patients being Alternaria, Botrytis, Candida, and Malassezia. Interestingly, Fusarium was the most common genus detected in the control group. Both AD patients and controls were also detectable for Proteobacteria, followed by Firmicutes, Actinobacteria, and Bacteroides for bacterial infection. At the family level, Burkholderiaceae and Staphylococcaceae exhibited higher levels in the brains of those with AD than the brains of the control group. Accordingly, there is thought to be a viscous cycle of uncontrolled neuroinflammation and neurodegeneration in the brain, caused by agents such as the herpes simplex virus type 1 (HSV1), Chlamydophilapneumonia, and Spirochetes, and the presence of apolipoprotein E4 (APOE4), which is associated with an increased proinflammatory response in the immune system. Systemic proinflammatory cytokines are produced by microorganisms such as Cytomegalovirus, Helicobacter pylori, and those related to periodontal infections. These can then cross the blood–brain barrier (BBB) and lead to the onset of dementia. Here, we reviewed the relationship between the etiology of AD and microorganisms (such as bacterial pathogens, Herpesviridae viruses, and periodontal pathogens) according to the evidence available to understand the pathogenesis of AD. These findings might guide a targeted anti-inflammatory therapeutic approach to AD.
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Andersen JV, Schousboe A, Verkhratsky A. Astrocyte energy and neurotransmitter metabolism in Alzheimer's disease: integration of the glutamate/GABA-glutamine cycle. Prog Neurobiol 2022; 217:102331. [PMID: 35872221 DOI: 10.1016/j.pneurobio.2022.102331] [Citation(s) in RCA: 71] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/14/2022] [Accepted: 07/19/2022] [Indexed: 02/06/2023]
Abstract
Astrocytes contribute to the complex cellular pathology of Alzheimer's disease (AD). Neurons and astrocytes function in close collaboration through neurotransmitter recycling, collectively known as the glutamate/GABA-glutamine cycle, which is essential to sustain neurotransmission. Neurotransmitter recycling is intimately linked to astrocyte energy metabolism. In the course of AD, astrocytes undergo extensive metabolic remodeling, which may profoundly affect the glutamate/GABA-glutamine cycle. The consequences of altered astrocyte function and metabolism in relation to neurotransmitter recycling are yet to be comprehended. Metabolic alterations of astrocytes in AD deprive neurons of metabolic support, thereby contributing to synaptic dysfunction and neurodegeneration. In addition, several astrocyte-specific components of the glutamate/GABA-glutamine cycle, including glutamine synthesis and synaptic neurotransmitter uptake, are perturbed in AD. Integration of the complex astrocyte biology within the context of AD is essential for understanding the fundamental mechanisms of the disease, while restoring astrocyte metabolism may serve as an approach to arrest or even revert clinical progression of AD.
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Affiliation(s)
- Jens V Andersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
| | - Arne Schousboe
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, IKERBASQUE, 48011 Bilbao, Spain; Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, LT-01102 Vilnius, Lithuania.
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22
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Fan S, Li L, Liu L, Li H, Xian X, Li W. Ceftriaxone Suppresses Group II Metabotropic Glutamate Receptor Expression Contributing to Reversal of Recognition Memory Deficits of Amyloid Precursor Protein/Presenilin 1 AD Mice. Front Neurosci 2022; 16:905403. [PMID: 35860293 PMCID: PMC9289516 DOI: 10.3389/fnins.2022.905403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Group II metabotropic glutamate receptors (Group II mGluRs) are the peri-synaptic receptor of glutamatergic neurons and negatively regulate glutamate release from presynaptic neurons. Glutamate in the synaptic cleft is mainly taken into astrocytes by glutamate transporter-1 (GLT-1), which is primarily expressed in astrocytes. Increasing evidence showed that inhibiting or suppressing the activation of Group II mGluRs would contribute to the improvement of learning and memory deficits in Alzheimer’s disease (AD) animal models. Ceftriaxone (Cef) has been reported to alleviate the spatial memory deficits in AD model mice by improving GLT-1-related clearance and metabolism of glutamate. Therefore, the present study further investigates the improving effect of Cef on recognition memory deficits and the involvement of Group II mGluRs in the process using the APP/PS1 AD mouse model. Novel object recognition tests showed that the Cef treatment significantly improved the recognition memory deficits of the AD mice. The Western blot and immunohistochemistry analysis showed that the Cef treatment significantly suppressed the upregulation of Group II mGluRs expression in APP/PS1 AD mice. The above suppression effect of Cef was blocked by dihydrokainic acid, an inhibitor of GLT-1 uptake activity. Furthermore, the Cef treatment significantly restored the downregulation in the downstream molecules of Group II mGluRs activation, including the expression of PKA and phosphorylated SNAP-25 in the APP/PS1 AD mice. The Cef treatment had no effect on the content of Aβ40 and Aβ42 in the hippocampus of APP/PS1 AD mice. The above results suggested that the suppression of Group II mGluRs contributed to the Cef-induced reversal of the recognition memory deficits in APP/PS1 AD mice.
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Affiliation(s)
- ShuJuan Fan
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - Li Li
- Department of Central Laboratory, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - LiRong Liu
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - He Li
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - XiaoHui Xian
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
- *Correspondence: XiaoHui Xian,
| | - WenBin Li
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
- WenBin Li,
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23
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Liu C. The Role of Mesenchymal Stem Cells in Regulating Astrocytes-Related Synapse Dysfunction in Early Alzheimer’s Disease. Front Neurosci 2022; 16:927256. [PMID: 35801178 PMCID: PMC9253587 DOI: 10.3389/fnins.2022.927256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 05/31/2022] [Indexed: 11/17/2022] Open
Abstract
Alzheimer’s disease (AD), a neurodegenerative disease, is characterized by the presence of extracellular amyloid-β (Aβ) aggregates and intracellular neurofibrillary tangles formed by hyperphosphorylated tau as pathological features and the cognitive decline as main clinical features. An important cellular correlation of cognitive decline in AD is synapse loss. Soluble Aβ oligomer has been proposed to be a crucial early event leading to synapse dysfunction in AD. Astrocytes are crucial for synaptic formation and function, and defects in astrocytic activation and function have been suggested in the pathogenesis of AD. Astrocytes may contribute to synapse dysfunction at an early stage of AD by participating in Aβ metabolism, brain inflammatory response, and synaptic regulation. While mesenchymal stem cells can inhibit astrogliosis, and promote non-reactive astrocytes. They can also induce direct regeneration of neurons and synapses. This review describes the role of mesenchymal stem cells and underlying mechanisms in regulating astrocytes-related Aβ metabolism, neuroinflammation, and synapse dysfunction in early AD, exploring the open questions in this field.
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Morrone CD, Lai AY, Bishay J, Hill ME, McLaurin J. Parvalbumin neuroplasticity compensates for somatostatin impairment, maintaining cognitive function in Alzheimer's disease. Transl Neurodegener 2022; 11:26. [PMID: 35501886 PMCID: PMC9063209 DOI: 10.1186/s40035-022-00300-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 03/31/2022] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Patient-to-patient variability in the degree to which β-amyloid, tau and neurodegeneration impact cognitive decline in Alzheimer's disease (AD) complicates disease modeling and treatment. However, the underlying mechanisms leading to cognitive resilience are not resolved. We hypothesize that the variability in cognitive function and loss relates to neuronal resilience of the hippocampal GABAergic network. METHODS We compared TgF344-AD and non-transgenic littermate rats at 9, 12, and 15 months of age. Neurons, β-amyloid plaques and tau inclusions were quantified in hippocampus and entorhinal cortex. Somatostatin (SST) and parvalbumin (PVB) interneurons were traced to examine hippocampal neuroplasticity and cognition was tested in the Barnes maze. RESULTS The 9-month-old TgF344-AD rats exhibited loss of neurons in the entorhinal cortex and hippocampus. Hippocampal neuronal compensation was observed in 12-month TgF344-AD rats, with upregulation of GABAergic interneuronal marker. By 15 months, the TgF344-AD rats had robust loss of excitatory and inhibitory neurons. β-Amyloid and tau pathology accumulated continuously across age. SST interneurons exhibited tau inclusions and atrophy from 9 months, whereas PVB interneurons were resilient until 15 months. The hippocampal PVB circuit underwent neuroplastic reorganization with increased dendritic length and complexity in 9- and 12-month-old TgF344-AD rats, before atrophy at 15 months. Strikingly, 12-month-old TgF344-AD rats were resilient in executive function and cognitive flexibility. Cognitive resilience in TgF344-AD rats occurred as maintenance of function between 9 and 12 months of age despite progressive spatial memory deficits, and was sustained by PVB neuroplasticity. CONCLUSIONS Our results demonstrate the inherent neuronal processes leading to cognitive maintenance, and describe a novel finding of endogenous cognitive resilience in an AD model.
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Affiliation(s)
| | - Aaron Yenhsin Lai
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON M4N 3M5 Canada
| | - Jossana Bishay
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON M4N 3M5 Canada
| | - Mary Elizabeth Hill
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON M4N 3M5 Canada
| | - JoAnne McLaurin
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON M4N 3M5 Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8 Canada
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Cortical axon sub-population maintains density, but not turnover, of en passant boutons in the aged APP/PS1 amyloidosis model. Neurobiol Aging 2022; 115:29-38. [DOI: 10.1016/j.neurobiolaging.2022.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/10/2022] [Accepted: 03/12/2022] [Indexed: 11/21/2022]
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Aramideh JA, Vidal-Itriago A, Morsch M, Graeber MB. Cytokine Signalling at the Microglial Penta-Partite Synapse. Int J Mol Sci 2021; 22:ijms222413186. [PMID: 34947983 PMCID: PMC8708012 DOI: 10.3390/ijms222413186] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 12/28/2022] Open
Abstract
Microglial cell processes form part of a subset of synaptic contacts that have been dubbed microglial tetra-partite or quad-partite synapses. Since tetrapartite may also refer to the presence of extracellular matrix components, we propose the more precise term microglial penta-partite synapse for synapses that show a microglial cell process in close physical proximity to neuronal and astrocytic synaptic constituents. Microglial cells are now recognised as key players in central nervous system (CNS) synaptic changes. When synaptic plasticity involving microglial penta-partite synapses occurs, microglia may utilise their cytokine arsenal to facilitate the generation of new synapses, eliminate those that are not needed anymore, or modify the molecular and structural properties of the remaining synaptic contacts. In addition, microglia–synapse contacts may develop de novo under pathological conditions. Microglial penta-partite synapses have received comparatively little attention as unique sites in the CNS where microglial cells, cytokines and other factors they release have a direct influence on the connections between neurons and their function. It concerns our understanding of the penta-partite synapse where the confusion created by the term “neuroinflammation” is most counterproductive. The mere presence of activated microglia or the release of their cytokines may occur independent of inflammation, and penta-partite synapses are not usually active in a neuroimmunological sense. Clarification of these details is the main purpose of this review, specifically highlighting the relationship between microglia, synapses, and the cytokines that can be released by microglial cells in health and disease.
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Affiliation(s)
- Jason Abbas Aramideh
- Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Andres Vidal-Itriago
- Faculty of Medicine, Health & Human Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia; (A.V.-I.); (M.M.)
| | - Marco Morsch
- Faculty of Medicine, Health & Human Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia; (A.V.-I.); (M.M.)
| | - Manuel B. Graeber
- Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia;
- Correspondence:
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27
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Sanchez-Varo R, Sanchez-Mejias E, Fernandez-Valenzuela JJ, De Castro V, Mejias-Ortega M, Gomez-Arboledas A, Jimenez S, Sanchez-Mico MV, Trujillo-Estrada L, Moreno-Gonzalez I, Baglietto-Vargas D, Vizuete M, Davila JC, Vitorica J, Gutierrez A. Plaque-Associated Oligomeric Amyloid-Beta Drives Early Synaptotoxicity in APP/PS1 Mice Hippocampus: Ultrastructural Pathology Analysis. Front Neurosci 2021; 15:752594. [PMID: 34803589 PMCID: PMC8600261 DOI: 10.3389/fnins.2021.752594] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/04/2021] [Indexed: 01/14/2023] Open
Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder characterized by initial memory impairments that progress to dementia. In this sense, synaptic dysfunction and loss have been established as the pathological features that best correlate with the typical early cognitive decline in this disease. At the histopathological level, post mortem AD brains typically exhibit intraneuronal neurofibrillary tangles (NFTs) along with the accumulation of amyloid-beta (Abeta) peptides in the form of extracellular deposits. Specifically, the oligomeric soluble forms of Abeta are considered the most synaptotoxic species. In addition, neuritic plaques are Abeta deposits surrounded by activated microglia and astroglia cells together with abnormal swellings of neuronal processes named dystrophic neurites. These periplaque aberrant neurites are mostly presynaptic elements and represent the first pathological indicator of synaptic dysfunction. In terms of losing synaptic proteins, the hippocampus is one of the brain regions most affected in AD patients. In this work, we report an early decline in spatial memory, along with hippocampal synaptic changes, in an amyloidogenic APP/PS1 transgenic model. Quantitative electron microscopy revealed a spatial synaptotoxic pattern around neuritic plaques with significant loss of periplaque synaptic terminals, showing rising synapse loss close to the border, especially in larger plaques. Moreover, dystrophic presynapses were filled with autophagic vesicles in detriment of the presynaptic vesicular density, probably interfering with synaptic function at very early synaptopathological disease stages. Electron immunogold labeling showed that the periphery of amyloid plaques, and the associated dystrophic neurites, was enriched in Abeta oligomers supporting an extracellular location of the synaptotoxins. Finally, the incubation of primary neurons with soluble fractions derived from 6-month-old APP/PS1 hippocampus induced significant loss of synaptic proteins, but not neuronal death. Indeed, this preclinical transgenic model could serve to investigate therapies targeted at initial stages of synaptic dysfunction relevant to the prodromal and early AD.
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Affiliation(s)
- Raquel Sanchez-Varo
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Departamento Fisiologia Humana, Histologia Humana, Anatomia Patologica y Educacion Fisica y Deportiva, Facultad de Medicina, Universidad de Málaga, Málaga, Spain
| | - Elisabeth Sanchez-Mejias
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Juan Jose Fernandez-Valenzuela
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Vanessa De Castro
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
| | - Marina Mejias-Ortega
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Angela Gomez-Arboledas
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Sebastian Jimenez
- Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Departamento Bioquimica y Biologia Molecular, Facultad de Farmacia, Universidad de Sevilla, Seville, Spain.,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocio CSIC/Universidad de Sevilla, Seville, Spain
| | - Maria Virtudes Sanchez-Mico
- Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Departamento Bioquimica y Biologia Molecular, Facultad de Farmacia, Universidad de Sevilla, Seville, Spain.,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocio CSIC/Universidad de Sevilla, Seville, Spain
| | - Laura Trujillo-Estrada
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Ines Moreno-Gonzalez
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Department of Neurology, McGovern Medical School, UTHealth Science Center at Houston, Houston, TX, United States
| | - David Baglietto-Vargas
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Marisa Vizuete
- Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Departamento Bioquimica y Biologia Molecular, Facultad de Farmacia, Universidad de Sevilla, Seville, Spain.,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocio CSIC/Universidad de Sevilla, Seville, Spain
| | - Jose Carlos Davila
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Javier Vitorica
- Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Departamento Bioquimica y Biologia Molecular, Facultad de Farmacia, Universidad de Sevilla, Seville, Spain.,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocio CSIC/Universidad de Sevilla, Seville, Spain
| | - Antonia Gutierrez
- Departamento Biologia Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.,Centro de Investigación Biomedica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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Mengr A, Hrubá L, Exnerová A, Holubová M, Popelová A, Železná B, Kuneš J, Maletínská L. Palmitoylated prolactin-releasing peptide reduced Aβ plaques and microgliosis in the cerebellum: APP/PS1 mice study. Curr Alzheimer Res 2021; 18:607-622. [PMID: 34551697 DOI: 10.2174/1567205018666210922110652] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/20/2021] [Accepted: 08/21/2021] [Indexed: 01/22/2023]
Abstract
BACKGROUND Prolactin-releasing peptide (PrRP) is a potential drug for the treatment of obesity and associated type 2 diabetes mellitus (T2DM) due to its strong anorexigenic and antidiabetic properties. In our recent study, the lipidized PrRP analog palm11-PrRP31 was proven to exert beneficial effects in APP/PS1 mice, a model of Alzheimer´s disease (AD)-like amyloid-β (Aβ) pathology, reducing the Aβ plaque load, microgliosis and astrocytosis in the hippocampus and cortex. OBJECTIVE In this study, we focused on the neuroprotective and anti-inflammatory effects of palm11-PrRP31 and its possible impact on synaptogenesis in the cerebellum of APP/PS1 mice, because others have suggested that cerebellar Aβ plaques contribute to cognitive deficits in AD. METHODS APP/PS1 mice were treated subcutaneously with palm11-PrRP31 for 2 months, then immunoblotting and immunohistochemistry were used to quantify pathological markers connected to AD, compared to control mice. RESULTS In the cerebella of 8 months old APP/PS1 mice, we found widespread Aβ plaques surrounded by activated microglia detected by ionized calcium-binding adapter molecule (Iba1), but no increase in astrocytic marker glial fibrillary acidic protein (GFAP) compared to controls. Interestingly, no difference in both presynaptic markers syntaxin1A and postsynaptic marker spinophilin was registered between APP/PS1 and control mice. Palm11-PrRP31 treatment significantly reduced the Aβ plaque load and microgliosis in the cerebellum. Furthermore, palm11-PrRP31 increased synaptogenesis and attenuated neuroinflammation and apoptosis in the hippocampus of APP/PS1 mice. CONCLUSION These results suggest palm11-PrRP31 is a promising agent for the treatment of neurodegenerative disorders.
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Affiliation(s)
- Anna Mengr
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Lucie Hrubá
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Aneta Exnerová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Martina Holubová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Andrea Popelová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Blanka Železná
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Jaroslav Kuneš
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
| | - Lenka Maletínská
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 166 10 Prague 6. Czech Republic
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29
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Kurucu H, Colom-Cadena M, Davies C, Wilkins L, King D, Rose J, Tzioras M, Tulloch JH, Smith C, Spires-Jones TL. Inhibitory synapse loss and accumulation of amyloid beta in inhibitory presynaptic terminals in Alzheimer's disease. Eur J Neurol 2021; 29:1311-1323. [PMID: 34331352 DOI: 10.1111/ene.15043] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE Synapse degeneration in Alzheimer's disease (AD) correlates strongly with cognitive decline. There is well-established excitatory synapse loss in AD with known contributions of pathological amyloid beta (Aβ) to excitatory synapse dysfunction and loss. Despite clear changes in circuit excitability in AD and model systems, relatively little is known about pathology in inhibitory synapses. METHODS Here human postmortem brain samples (n = 5 control, 10 AD cases) from temporal and occipital cortices were examined to investigate whether inhibitory synapses and neurons are lost in AD and whether Aβ may contribute to inhibitory synapse degeneration. Inhibitory neurons were counted in all six cortical layers using stereology software, and array tomography was used to examine synapse density and the accumulation of Aβ in synaptic terminals. RESULTS Differing inhibitory neuron densities were observed in the different cortical layers. The highest inhibitory neuron density was observed in layer 4 in both brain regions and the visual cortex had a higher inhibitory neuron density than the temporal cortex. There was significantly lower inhibitory neuron density in AD than in control cases in all six cortical layers. High-resolution array tomography imaging revealed plaque-associated loss of inhibitory synapses and accumulation of Aβ in a small subset of inhibitory presynaptic terminals with the most accumulation near amyloid plaques. CONCLUSIONS Inhibitory neuron and synapse loss in AD may contribute to disrupted excitatory/inhibitory balance and cognitive decline. Future work is warranted to determine whether targeting inhibitory synapse loss could be a useful therapeutic strategy.
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Affiliation(s)
- Hatice Kurucu
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Martí Colom-Cadena
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Caitlin Davies
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Lewis Wilkins
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Declan King
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Jamie Rose
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Makis Tzioras
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Jane H Tulloch
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
| | - Colin Smith
- Centre for Clinical Brain Sciences and Sudden Death Brain Bank, University of Edinburgh, Edinburgh, UK
| | - Tara L Spires-Jones
- University of Edinburgh Centre for Discovery Brain Sciences and UK Dementia Research Institute, Edinburgh, UK
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30
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Sharma C, Kim SR. Linking Oxidative Stress and Proteinopathy in Alzheimer's Disease. Antioxidants (Basel) 2021; 10:antiox10081231. [PMID: 34439479 PMCID: PMC8388980 DOI: 10.3390/antiox10081231] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 07/26/2021] [Accepted: 07/28/2021] [Indexed: 12/14/2022] Open
Abstract
Proteinopathy and excessive production of reactive oxygen species (ROS), which are the principal features observed in the Alzheimer’s disease (AD) brain, contribute to neuronal toxicity. β-amyloid and tau are the primary proteins responsible for the proteinopathy (amyloidopathy and tauopathy, respectively) in AD, which depends on ROS production; these aggregates can also generate ROS. These mechanisms work in concert and reinforce each other to drive the pathology observed in the aging brain, which primarily involves oxidative stress (OS). This, in turn, triggers neurodegeneration due to the subsequent loss of synapses and neurons. Understanding these interactions may thus aid in the identification of potential neuroprotective therapies that could be clinically useful. Here, we review the role of β-amyloid and tau in the activation of ROS production. We then further discuss how free radicals can influence structural changes in key toxic intermediates and describe the putative mechanisms by which OS and oligomers cause neuronal death.
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Affiliation(s)
- Chanchal Sharma
- School of Life Sciences, Kyungpook National University, Daegu 41566, Korea;
- BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Korea
| | - Sang Ryong Kim
- School of Life Sciences, Kyungpook National University, Daegu 41566, Korea;
- BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Korea
- Brain Science and Engineering Institute, Kyungpook National University, Daegu 41944, Korea
- Correspondence: ; Tel.: +82-53-950-7362; Fax: +82-53-943-2762
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31
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Fan S, Li L, Xian X, Liu L, Gao J, Li W. Ceftriaxone regulates glutamate production and vesicular assembly in presynaptic terminals through GLT-1 in APP/PS1 mice. Neurobiol Learn Mem 2021; 183:107480. [PMID: 34153453 DOI: 10.1016/j.nlm.2021.107480] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 05/13/2021] [Accepted: 06/16/2021] [Indexed: 10/21/2022]
Abstract
Perturbations in the glutamate-glutamine cycle and glutamate release from presynaptic terminals have been involved in the development of cognitive deficits in Alzheimer's disease (AD) patients and mouse models. Glutamate transporter-1 (GLT-1) removes glutamate from the synaptic cleft and transports it into astrocytes, where it is used as substrate for the glutamate-glutamine cycle. Ceftriaxone has been reported to improve cognitive deficits in AD mice by increasing GLT-1 expression, glutamate transformation to glutamine, and glutamine efflux from astrocytes. However, the impact of ceftriaxone on glutamine metabolism in neurons is unknown. The present study aimed to investigate whether ceftriaxone regulated the production and vesicular assembly of glutamate in the presynaptic terminals of neurons and to determine GLT-1 involvement in this process. We used the amyloid precursor protein (APP)/presenilin-1 (PS1) AD mouse model and GLT-1 knockdown APP/PS1 (GLT-1+/-/APP/PS1) mice. The expression levels of sodium-coupled neutral amino-acid transporter 1 (SNAT1) and vesicular glutamate transporters 1 and 2 (VGLUT1/2) were analyzed by immunofluorescence and immunohistochemistry staining as well as by Western blotting. Glutaminase activity was assayed by fluorometry. Ceftriaxone treatment significantly increased SNAT1 expression and glutaminase activity in neurons in APP/PS1 mice. Similarly, VGLUT1/2 levels were increased in the presynaptic terminals of APP/PS1 mice treated with ceftriaxone. The deletion of one GLT-1 allele in APP/PS1 mice prevented the ceftriaxone-induced upregulation of SNAT1 and VGLUT1/2 expression, indicating that GLT-1 played an important role in ceftriaxone effect. Based on the role of SNAT1, glutaminase, and VGLUT1/2 in the glutamate-glutamine cycle in neurons, the present results suggested that ceftriaxone improved the production and vesicular assembly of glutamate as a neurotransmitter in presynaptic terminals by acting on GLT-1 in APP/PS1 mice.
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Affiliation(s)
- ShuJuan Fan
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, PR China
| | - Li Li
- Central Laboratory, The Second Hospital of Hebei Medical University, 215 Heping West Road, Shijiazhuang 050000, PR China
| | - XiaoHui Xian
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, PR China.
| | - LiRong Liu
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, PR China
| | - JunXia Gao
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, PR China
| | - WenBin Li
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, PR China.
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32
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Ekundayo TC, Olasehinde TA, Okaiyeto K, Okoh AI. Microbial Pathogenesis and Pathophysiology of Alzheimer's Disease: A Systematic Assessment of Microorganisms' Implications in the Neurodegenerative Disease. Front Neurosci 2021; 15:648484. [PMID: 33994926 PMCID: PMC8113417 DOI: 10.3389/fnins.2021.648484] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/29/2021] [Indexed: 11/13/2022] Open
Abstract
Microbial infections have been linked to the pathogenesis and pathophysiology of Alzheimer's disease (AD) and other neurodegenerative diseases. The present study aimed to synthesise and assess global evidence of microbial pathogenesis and pathophysiology in AD (MPP-AD) and associated neurodegenerative conditions using integrated science mapping and content analytics to explore the associated research landscape. Relevant MPP-AD documents were retrieved from Web of Science and Scopus according to PRISMA principles and analysed for productivity/trend linked to authors/countries, thematic conceptual framework, and international collaborative networks. A total of 258 documents published from 136 sources to 39.42 average citations/document were obtained on MPP-AD. The co-authors per document were 7.6, and the collaboration index was 5.71. The annual research outputs increased tremendously in the last 6 years from 2014 to 2019, accounting for 66% compared with records in the early years from 1982 to 1990 (16%). The USA (n = 71, freq. = 30.34%), United Kingdom (n = 32, freq. = 13.68%) and China (n = 27, 11.54%) ranked in first three positions in term of country's productivity. Four major international collaboration clusters were found in MPP-AD research. The country collaboration network in MPP-AD was characteristic of sparse interaction and acquaintanceship (density = 0.11, diameter = 4). Overall, international collaboration is globally inadequate [centralisation statistics: degree (40.5%), closeness (4%), betweenness (23%), and eigenvector (76.7%)] against the robust authors' collaboration index of 5.71 in MPP-AD research. Furthermore, four conceptual thematic frameworks (CTF) namely, CTF#1, roles of microbial/microbiome infection and dysbiosis in cognitive dysfunctions; CTF#2, bacterial infection specific roles in dementia; CTF#3, the use of yeast as a model system for studying MPP-AD and remediation therapy; and CFT#4, flow cytometry elucidation of amyloid-beta and aggregation in Saccharomyces cerevisiae model. Finally, aetiology-based mechanisms of MPP-AD, namely, gut microbiota, bacterial infection, and viral infection, were comprehensively discussed. This study provides an overview of MPP-AD and serves as a stepping stone for future preparedness in MPP-AD-related research.
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Affiliation(s)
- Temitope Cyrus Ekundayo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa.,Department of Biological Sciences, University of Medical Sciences, Ondo, Nigeria
| | - Tosin Abiola Olasehinde
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa.,Nutrition and Toxicology Division, Food Technology Department, Federal Institute of Industrial Research Oshodi, Lagos, Nigeria
| | - Kunle Okaiyeto
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa.,Department of Environmental Health Sciences, College of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
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33
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Jin S, Cao Q, Yang F, Zhu H, Xu S, Chen Q, Wang Z, Lin Y, Cinar R, Pawlosky RJ, Zhang Y, Xiong W, Gao B, Koob GF, Lovinger DM, Zhang L. Brain ethanol metabolism by astrocytic ALDH2 drives the behavioural effects of ethanol intoxication. Nat Metab 2021; 3:337-351. [PMID: 33758417 PMCID: PMC8294184 DOI: 10.1038/s42255-021-00357-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 02/04/2021] [Indexed: 02/08/2023]
Abstract
Alcohol is among the most widely used psychoactive substances worldwide. Ethanol metabolites such as acetate, thought to be primarily the result of ethanol breakdown by hepatic aldehyde dehydrogenase 2 (ALDH2), contribute to alcohol's behavioural effects and alcoholism. Here, we show that ALDH2 is expressed in astrocytes in the mouse cerebellum and that ethanol metabolism by astrocytic ALDH2 mediates behavioural effects associated with ethanol intoxication. We show that ALDH2 is expressed in astrocytes in specific brain regions and that astrocytic, but not hepatocytic, ALDH2 is required to produce ethanol-derived acetate in the mouse cerebellum. Cerebellar astrocytic ALDH2 mediates low-dose ethanol-induced elevation of GABA levels, enhancement of tonic inhibition and impairment of balance and coordination skills. Thus, astrocytic ALDH2 controls the production, cellular and behavioural effects of alcohol metabolites in a brain-region-specific manner. Our data indicate that astrocytic ALDH2 is an important, but previously under-recognized, target in the brain to alter alcohol pharmacokinetics and potentially treat alcohol use disorder.
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Affiliation(s)
- Shiyun Jin
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
- Department of Anesthesiology, Second Affiliated Hospital, Anhui Medical University, Hefei, PR China
| | - Qi Cao
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Fanghan Yang
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Hongying Zhu
- Department of Neuroscience, University of Science and Technology of China, Hefei, PR China
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Qi Chen
- Department of Neuroscience, University of Science and Technology of China, Hefei, PR China
| | - Ziyi Wang
- Department of Neuroscience, University of Science and Technology of China, Hefei, PR China
| | - Yuhong Lin
- Laboratory for Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Resat Cinar
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Robert J Pawlosky
- Laboratory for Metabolic Control, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Ye Zhang
- Department of Anesthesiology, Second Affiliated Hospital, Anhui Medical University, Hefei, PR China
| | - Wei Xiong
- Department of Neuroscience, University of Science and Technology of China, Hefei, PR China
| | - Bin Gao
- Laboratory for Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - George F Koob
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - David M Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Li Zhang
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
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34
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Salami M. Interplay of Good Bacteria and Central Nervous System: Cognitive Aspects and Mechanistic Considerations. Front Neurosci 2021; 15:613120. [PMID: 33642976 PMCID: PMC7904897 DOI: 10.3389/fnins.2021.613120] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/06/2021] [Indexed: 12/12/2022] Open
Abstract
The human gastrointestinal tract hosts trillions of microorganisms that is called “gut microbiota.” The gut microbiota is involved in a wide variety of physiological features and functions of the body. Thus, it is not surprising that any damage to the gut microbiota is associated with disorders in different body systems. Probiotics, defined as living microorganisms with health benefits for the host, can support or restore the composition of the gut microbiota. Numerous investigations have proved a relationship between the gut microbiota with normal brain function as well as many brain diseases, in which cognitive dysfunction is a common clinical problem. On the other hand, increasing evidence suggests that the existence of a healthy gut microbiota is crucial for normal cognitive processing. In this regard, interplay of the gut microbiota and cognition has been under focus of recent researches. In the present paper, I review findings of the studies considering beneficial effects of either gut microbiota or probiotic bacteria on the brain cognitive function in the healthy and disease statuses.
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Affiliation(s)
- Mahmoud Salami
- Physiology Research Center, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.,Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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35
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Atkinson R, Leung J, Bender J, Kirkcaldie M, Vickers J, King A. TDP-43 mislocalization drives neurofilament changes in a novel model of TDP-43 proteinopathy. Dis Model Mech 2021; 14:dmm.047548. [PMID: 33408125 PMCID: PMC7888715 DOI: 10.1242/dmm.047548] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/17/2020] [Indexed: 12/21/2022] Open
Abstract
Mislocalization of the TAR DNA-binding protein 43 (TDP-43) from the nucleus to the cytoplasm is a common feature of neurodegenerative conditions such as amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). The downstream in vivo cellular effects of this mislocalization are not well understood. To investigate the impact of mislocalized TDP-43 on neuronal cell bodies, axons and axonal terminals, we utilized the mouse visual system to create a new model of TDP-43 proteinopathy. Mouse (C57BL/6J) retinal ganglion cells (RGCs) were transduced with GFP-tagged human wildtype TDP-43 (hTDP-WT-GFP) and human TDP-43 with a mutation in the nuclear localization sequence (hTDP-ΔNLS-GFP), to cause TDP-43 mislocalization, with ∼60% transduction efficiency achieved. Expression of both hTDP-WT-GFP and hTDP-ΔNLS-GFP resulted in changes to neurofilament expression, with cytoplasmic TDP-43 being associated with significantly (p<0.05) increased neurofilament heavy expression in the cell soma, and both forms of altered TDP-43 leading to significantly (p<0.05) decreased numbers of neurofilament-positive axons within the optic nerve. Alterations to neurofilament proteins were associated with significantly (p<0.05) increased microglial density in the optic nerve and retina. Furthermore expression of hTDP-WT-GFP was associated with a significant (p<0.05) increase in pre-synaptic input into RGCs in the retina. The current study has developed a new model allowing detailed examination of alterations to TDP-43 and will contribute to the knowledge of TDP-43-mediated neuronal alterations and degeneration.
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Affiliation(s)
- Rachel Atkinson
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - Jacqueline Leung
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - James Bender
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - Matthew Kirkcaldie
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - James Vickers
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
| | - Anna King
- Wicking Dementia Research and Education Centre, University of Tasmania, Medical Science Precinct, 17, Liverpool Street, Hobart, Tasmania, Australia 7000, Australia
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36
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Rombaut B, Kessels S, Schepers M, Tiane A, Paes D, Solomina Y, Piccart E, Hove DVD, Brône B, Prickaerts J, Vanmierlo T. PDE inhibition in distinct cell types to reclaim the balance of synaptic plasticity. Theranostics 2021; 11:2080-2097. [PMID: 33500712 PMCID: PMC7797685 DOI: 10.7150/thno.50701] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 11/17/2020] [Indexed: 02/06/2023] Open
Abstract
Synapses are the functional units of the brain. They form specific contact points that drive neuronal communication and are highly plastic in their strength, density, and shape. A carefully orchestrated balance between synaptogenesis and synaptic pruning, i.e., the elimination of weak or redundant synapses, ensures adequate synaptic density. An imbalance between these two processes lies at the basis of multiple neuropathologies. Recent evidence has highlighted the importance of glia-neuron interactions in the synaptic unit, emphasized by glial phagocytosis of synapses and local excretion of inflammatory mediators. These findings warrant a closer look into the molecular basis of cell-signaling pathways in the different brain cells that are related to synaptic plasticity. In neurons, intracellular second messengers, such as cyclic guanosine or adenosine monophosphate (cGMP and cAMP, respectively), are known mediators of synaptic homeostasis and plasticity. Increased levels of these second messengers in glial cells slow down inflammation and neurodegenerative processes. These multi-faceted effects provide the opportunity to counteract excessive synapse loss by targeting cGMP and cAMP pathways in multiple cell types. Phosphodiesterases (PDEs) are specialized degraders of these second messengers, rendering them attractive targets to combat the detrimental effects of neurological disorders. Cellular and subcellular compartmentalization of the specific isoforms of PDEs leads to divergent downstream effects for these enzymes in the various central nervous system resident cell types. This review provides a detailed overview on the role of PDEs and their inhibition in the context of glia-neuron interactions in different neuropathologies characterized by synapse loss. In doing so, it provides a framework to support future research towards finding combinational therapy for specific neuropathologies.
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37
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Fulopova B, Stuart KE, Bennett W, Bindoff A, King AE, Vickers JC, Canty AJ. Regional differences in beta amyloid plaque deposition and variable response to midlife environmental enrichment in the cortex of APP/PS1 mice. J Comp Neurol 2020; 529:1849-1862. [PMID: 33104234 DOI: 10.1002/cne.25060] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 01/21/2023]
Abstract
Environmentally enriched housing conditions can increase performance on cognitive tasks in APP/PS1 mice; however, the potential effects of environmental enrichment (EE) on disease modification in terms of pathological change are inconclusive. We hypothesized that previous contrasting findings may be attributable to regional differences in susceptibility to amyloid beta (Aβ) plaque deposition in cortical regions that are functionally associated with EE. We characterized fibrillar plaque deposition in 6, 12, and 18-22 months old APP/PS1 mice in the prefrontal (PFC), somatosensory (SS2), and primary motor cortex (M1). We found a significant increase in plaque load between 6 and 12 months in all regions. In animals over 12 months, only the PFC region continued to significantly accumulate plaques. Additionally, 12 months old animals subjected to 6 months of EE showed improved spatial navigation and had significantly fewer plaques in M1 and SS2, but not in the PFC. These findings suggest that the PFC region is selectively susceptible to Aβ deposition and less responsive to the attenuating effects of EE. In contrast, M1 and SS2 regions plateau with respect to Aβ deposition by 12 months of age and are susceptible to amyloid pathology modification by midlife EE.
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Affiliation(s)
- Barbora Fulopova
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Kimberley E Stuart
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - William Bennett
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Aidan Bindoff
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Anna E King
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - James C Vickers
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Alison J Canty
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
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38
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Téglás T, Ábrahám D, Jókai M, Kondo S, Mohammadi R, Fehér J, Szabó D, Wilhelm M, Radák Z. Exercise combined with a probiotics treatment alters the microbiome, but moderately affects signalling pathways in the liver of male APP/PS1 transgenic mice. Biogerontology 2020; 21:807-815. [PMID: 32812166 PMCID: PMC7541368 DOI: 10.1007/s10522-020-09895-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/07/2020] [Indexed: 12/11/2022]
Abstract
It has been demonstrated that physical exercise and probiotic supplementation delay the progress of Alzheimer's Disease (AD) in male APP/PS1TG mice. However, it has also been suggested that both exercise and AD have systemic effects. We have studied the effects of exercise training and probiotic treatment on microbiome and biochemical signalling proteins in the liver. The results suggest that liver is under oxidative stress, since SOD2 levels of APP/PS1 mice were decreased when compared to a wild type of mice. Exercise training prevented this decrease. We did not find significant changes in COX4, SIRT3, PGC-1a or GLUT4 levels, while the changes in pAMPK/AMPK, pmTOR/mTOR, pS6/S6 and NRF2 levels were randomly modulated. The data suggest that exercise and probiotics-induced changes in microbiome do not strongly affect mitochondrial density or protein synthesis-related AMPK/mTOR/S6 pathways in the liver of these animals.
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Affiliation(s)
- Tímea Téglás
- Research Center for Molecular Exercise Science, University of Physical Education, Alkotas str. 44, Budapest, 1123, Hungary
| | - Dóra Ábrahám
- Research Center for Molecular Exercise Science, University of Physical Education, Alkotas str. 44, Budapest, 1123, Hungary
| | - Mátyás Jókai
- Research Center for Molecular Exercise Science, University of Physical Education, Alkotas str. 44, Budapest, 1123, Hungary
| | - Saki Kondo
- Research Center for Molecular Exercise Science, University of Physical Education, Alkotas str. 44, Budapest, 1123, Hungary.,Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, 113-8654, Japan
| | - Rezieh Mohammadi
- Research Center for Molecular Exercise Science, University of Physical Education, Alkotas str. 44, Budapest, 1123, Hungary
| | - János Fehér
- Ophthalmology Unit, NESMOS Department, Sant'Andrea Hospital, Faculty of Medicine and Psychology, "Sapienza" University of Rome, Rome, Italy
| | - Dóra Szabó
- Semmelweis University, Budapest, Hungary
| | - Marta Wilhelm
- Institute of Sport Sciences and Physical Education, Faculty of Science, University of Pécs, Pecs, 2020, Hungary.,Faculty of Sport Sciences, Waseda University, Saitama, 359-1192, Japan
| | - Zsolt Radák
- Research Center for Molecular Exercise Science, University of Physical Education, Alkotas str. 44, Budapest, 1123, Hungary. .,Institute of Sport Sciences and Physical Education, Faculty of Science, University of Pécs, Pecs, 2020, Hungary. .,Faculty of Sport Sciences, Waseda University, Saitama, 359-1192, Japan.
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39
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Afzal M, Mazhar SF, Sana S, Naeem M, Rasool MH, Saqalein M, Nisar MA, Rasool M, Bilal M, Khan AA, Khurshid M. Neurological and cognitive significance of probiotics: a holy grail deciding individual personality. Future Microbiol 2020; 15:1059-1074. [PMID: 32755361 DOI: 10.2217/fmb-2019-0143] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The role of the human microbiome in the brain and behavioral development is an area of increasing attention. Recent investigations have found that diverse mechanisms and signals including the immune, endocrine and neural associations are responsible for the communication between gut microbiota and the brain. The studies have suggested that alteration of intestinal microbiota using probiotic formulations may offer a significant role in the maturation and organization of the brain and can shape the brain and behavior as well as mood and cognition in human subjects. The understanding of the possible impact of gut microflora on neurological function is a promising phenomenon that can surely transform the neurosciences and may decipher the novel etiologies for neurodegenerative and psychiatric disorders.
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Affiliation(s)
- Muhammad Afzal
- College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Pakistan
| | - Sayyeda Farwa Mazhar
- College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Pakistan
| | - Sadia Sana
- College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Pakistan
| | - Muhammad Naeem
- College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Pakistan
| | | | - Muhammad Saqalein
- Department of Microbiology, Government College University Faisalabad, Pakistan
| | - Muhammad Atif Nisar
- Department of Microbiology, Government College University Faisalabad, Pakistan
| | - Maria Rasool
- College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Pakistan.,Department of Microbiology, Government College University Faisalabad, Pakistan
| | - Muhammad Bilal
- School of Life Science & Food Engineering, Huaiyin Institute of Technology, Huaian, Jiangsu, China
| | - Abdul Arif Khan
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Mohsin Khurshid
- Department of Microbiology, Government College University Faisalabad, Pakistan
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40
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Ahmad F, Liu P. Synaptosome as a tool in Alzheimer's disease research. Brain Res 2020; 1746:147009. [PMID: 32659233 DOI: 10.1016/j.brainres.2020.147009] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/21/2020] [Accepted: 07/04/2020] [Indexed: 12/29/2022]
Abstract
Synapse dysfunction is an integral feature of Alzheimer's disease (AD) pathophysiology. In fact, prodromal manifestation of structural and functional deficits in synapses much prior to appearance of overt pathological hallmarks of the disease indicates that AD might be considered as a degenerative disorder of the synapses. Several research instruments and techniques have allowed us to study synaptic function and plasticity and their alterations in pathological conditions, such as AD. One such tool is the biochemically isolated preparations of detached and resealed synaptic terminals, the "synaptosomes". Because of the preservation of many of the physiological processes such as metabolic and enzymatic activities, synaptosomes have proved to be an indispensable ex vivo model system to study synapse physiology both when isolated from fresh or cryopreserved tissues, and from animal or human post-mortem tissues. This model system has been tremendously successful in the case of post-mortem tissues because of their accessibility relative to acute brain slices or cultures. The current review details the use of synaptosomes in AD research and its potential as a valuable tool in furthering our understanding of the pathogenesis and in devising and testing of therapeutic strategies for the disease.
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Affiliation(s)
- Faraz Ahmad
- Department of Anatomy, School of Biomedical Sciences, Brain Research New Zealand, University of Otago, Dunedin, New Zealand.
| | - Ping Liu
- Department of Anatomy, School of Biomedical Sciences, Brain Research New Zealand, University of Otago, Dunedin, New Zealand
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41
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Yeung JHY, Calvo-Flores Guzmán B, Palpagama TH, Ethiraj J, Zhai Y, Tate WP, Peppercorn K, Waldvogel HJ, Faull RLM, Kwakowsky A. Amyloid-beta 1-42 induced glutamatergic receptor and transporter expression changes in the mouse hippocampus. J Neurochem 2020; 155:62-80. [PMID: 32491248 DOI: 10.1111/jnc.15099] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 12/22/2022]
Abstract
Alzheimer's disease (AD) is the leading type of dementia worldwide. With an increasing burden of an aging population coupled with the lack of any foreseeable cure, AD warrants the current intense research effort on the toxic effects of an increased concentration of beta-amyloid (Aβ) in the brain. Glutamate is the main excitatory brain neurotransmitter and it plays an essential role in the function and health of neurons and neuronal excitability. While previous studies have shown alterations in expression of glutamatergic signaling components in AD, the underlying mechanisms of these changes are not well understood. This is the first comprehensive anatomical study to characterize the subregion- and cell layer-specific long-term effect of Aβ1-42 on the expression of specific glutamate receptors and transporters in the mouse hippocampus, using immunohistochemistry with confocal microscopy. Outcomes are examined 30 days after Aβ1-42 stereotactic injection in aged male C57BL/6 mice. We report significant decreases in density of the glutamate receptor subunit GluA1 and the vesicular glutamate transporter (VGluT) 1 in the conus ammonis 1 region of the hippocampus in the Aβ1-42 injected mice compared with artificial cerebrospinal fluid injected and naïve controls, notably in the stratum oriens and stratum radiatum. GluA1 subunit density also decreased within the dentate gyrus dorsal stratum moleculare in Aβ1-42 injected mice compared with artificial cerebrospinal fluid injected controls. These changes are consistent with findings previously reported in the human AD hippocampus. By contrast, glutamate receptor subunits GluA2, GluN1, GluN2A, and VGluT2 showed no changes in expression. These findings indicate that Aβ1-42 induces brain region and layer specific expression changes of the glutamatergic receptors and transporters, suggesting complex and spatial vulnerability of this pathway during development of AD neuropathology. Read the Editorial Highlight for this article on page 7. Cover Image for this issue: https://doi.org/10.1111/jnc.14763.
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Affiliation(s)
- Jason H Y Yeung
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Beatriz Calvo-Flores Guzmán
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Thulani H Palpagama
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Jayarjun Ethiraj
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Ying Zhai
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Warren P Tate
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Katie Peppercorn
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Henry J Waldvogel
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Richard L M Faull
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Andrea Kwakowsky
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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Melatonin regulates mitochondrial dynamics and alleviates neuron damage in prion diseases. Aging (Albany NY) 2020; 12:11139-11151. [PMID: 32526704 PMCID: PMC7346071 DOI: 10.18632/aging.103328] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 04/17/2020] [Indexed: 12/30/2022]
Abstract
Prion diseases are neurodegenerative diseases associated with neuron damage and behavioral disorders in animals and humans. Melatonin is a potent antioxidant and is used to treat a variety of diseases. We investigated the neuroprotective effect of melatonin on prion-induced damage in N2a cells. N2a cells were pretreated with 10 μM melatonin for 1 hour followed by incubation with 100 μM PrP106-126 for 24 hours. Melatonin markedly alleviated PrP106-126-induced apoptosis of N2a cells, and inhibited PrP106-126-induced mitochondrial abnormality and dysfunction, including mitochondrial fragmentation and overproduction of reactive oxygen species (ROS), suppression of ATP, reduced mitochondrial membrane potential (MMP), and altered mitochondrial dynamic proteins dynamin-related protein 1 (DRP1) and optic atrophy protein 1 (OPA1). Our findings identify that pretreatment with melatonin prevents the deleterious effects of PrPSc on mitochondrial function and dynamics, protects synapses and alleviates neuron damage. Melatonin could be a novel and effective medication in the therapy of prion diseases.
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43
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Li S, Selkoe DJ. A mechanistic hypothesis for the impairment of synaptic plasticity by soluble Aβ oligomers from Alzheimer's brain. J Neurochem 2020; 154:583-597. [PMID: 32180217 DOI: 10.1111/jnc.15007] [Citation(s) in RCA: 138] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 02/28/2020] [Accepted: 03/02/2020] [Indexed: 12/18/2022]
Abstract
It is increasingly accepted that early cognitive impairment in Alzheimer's disease results in considerable part from synaptic dysfunction caused by the accumulation of a range of oligomeric assemblies of amyloid β-protein (Aβ). Most studies have used synthetic Aβ peptides to explore the mechanisms of memory deficits in rodent models, but recent work suggests that Aβ assemblies isolated from human (AD) brain tissue are far more potent and disease-relevant. Although reductionist experiments show Aβ oligomers to impair synaptic plasticity and neuronal viability, the responsible mechanisms are only partly understood. Glutamatergic receptors, GABAergic receptors, nicotinic receptors, insulin receptors, the cellular prion protein, inflammatory mediators, and diverse signaling pathways have all been suggested. Studies using AD brain-derived soluble Aβ oligomers suggest that only certain bioactive forms (principally small, diffusible oligomers) can disrupt synaptic plasticity, including by binding to plasma membranes and changing excitatory-inhibitory balance, perturbing mGluR, PrP, and other neuronal surface proteins, down-regulating glutamate transporters, causing glutamate spillover, and activating extrasynaptic GluN2B-containing NMDA receptors. We synthesize these emerging data into a mechanistic hypothesis for synaptic failure in Alzheimer's disease that can be modified as new knowledge is added and specific therapeutics are developed.
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Affiliation(s)
- Shaomin Li
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Dennis J Selkoe
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
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44
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Guo Q, Xu S, Yang P, Wang P, Lu S, Sheng D, Qian K, Cao J, Lu W, Zhang Q. A dual-ligand fusion peptide improves the brain-neuron targeting of nanocarriers in Alzheimer's disease mice. J Control Release 2020; 320:347-362. [DOI: 10.1016/j.jconrel.2020.01.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 12/17/2022]
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45
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Cardozo PL, de Lima IBQ, Maciel EMA, Silva NC, Dobransky T, Ribeiro FM. Synaptic Elimination in Neurological Disorders. Curr Neuropharmacol 2020; 17:1071-1095. [PMID: 31161981 PMCID: PMC7052824 DOI: 10.2174/1570159x17666190603170511] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/23/2019] [Accepted: 05/31/2019] [Indexed: 12/12/2022] Open
Abstract
Synapses are well known as the main structures responsible for transmitting information through the release and recognition of neurotransmitters by pre- and post-synaptic neurons. These structures are widely formed and eliminated throughout the whole lifespan via processes termed synaptogenesis and synaptic pruning, respectively. Whilst the first pro-cess is needed for ensuring proper connectivity between brain regions and also with the periphery, the second phenomenon is important for their refinement by eliminating weaker and unnecessary synapses and, at the same time, maintaining and fa-voring the stronger ones, thus ensuring proper synaptic transmission. It is well-known that synaptic elimination is modulated by neuronal activity. However, only recently the role of the classical complement cascade in promoting this phenomenon has been demonstrated. Specifically, microglial cells recognize activated complement component 3 (C3) bound to synapses tar-geted for elimination, triggering their engulfment. As this is a highly relevant process for adequate neuronal functioning, dis-ruptions or exacerbations in synaptic pruning could lead to severe circuitry alterations that could underlie neuropathological alterations typical of neurological and neuropsychiatric disorders. In this review, we focus on discussing the possible in-volvement of excessive synaptic elimination in Alzheimer’s disease, as it has already been reported dendritic spine loss in post-synaptic neurons, increased association of complement proteins with its synapses and, hence, augmented microglia-mediated pruning in animal models of this disorder. In addition, we briefly discuss how this phenomenon could be related to other neurological disorders, including multiple sclerosis and schizophrenia.
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Affiliation(s)
- Pablo L Cardozo
- Laboratório de Neurobioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Izabella B Q de Lima
- Laboratório de Neurobioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Esther M A Maciel
- Laboratório de Neurobioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Nathália C Silva
- Laboratório de Neurobioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Fabíola M Ribeiro
- Laboratório de Neurobioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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46
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Giuliani A, Sivilia S, Baldassarro VA, Gusciglio M, Lorenzini L, Sannia M, Calzà L, Giardino L. Age-Related Changes of the Neurovascular Unit in the Cerebral Cortex of Alzheimer Disease Mouse Models: A Neuroanatomical and Molecular Study. J Neuropathol Exp Neurol 2019; 78:101-112. [PMID: 30629191 DOI: 10.1093/jnen/nly125] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
We describe age-related histological structure and molecular changes of the neurovascular unit (NVU) in the cerebral cortex of Tg2576 and age-matched wild-type (WT) mice. Major results can be summarized as follows: (i) β-amyloid (6E10)-immunoreactivity progressively increases in neurons and astrocytes of Tg2576 mice, reaching the highest concentration at 5 months and then decreasing as soon as extracellular plaque deposition begins; (ii) the synaptic puncta density of glutamatergic and GABAergic neurons in Tg2576 mice is unbalanced versus WT at all investigated ages, with a decrease in synaptophysin and VGLUT1; density of VGAT contacts is higher in 27-month-old Tg2576 versus WT mice; (iii) capillary density is higher in 5-month-old Tg2576 versus WT mice, then decreases to a lower density at 27 months, when the capillary-astrocyte interface is lower; and (iv) mRNA expression of genes involved in microvessel dynamics indicates age- and genotype-dependent changes in the expression levels of hypoxia-related genes, i.e. the highest level is in 5-month-old animals and there is impaired regulation in Tg2576. We conclude that at 5 months, when learning and memory impairment is already present in the absence of extracellular amyloid plaque deposition, Tg2576 mice display alterations in the structure and molecular regulation of the NVU.
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Affiliation(s)
- Alessandro Giuliani
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy
| | | | - Vito Antonio Baldassarro
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy.,IRET Foundation, Ozzano Emilia, Italy.,Pharmacy and Biotechnology Department (FaBiT), University of Bologna, Bologna, Italy
| | | | - Luca Lorenzini
- IRET Foundation, Ozzano Emilia, Italy.,Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy
| | - Michele Sannia
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy.,Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy
| | - Laura Calzà
- IRET Foundation, Ozzano Emilia, Italy.,Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,Pharmacy and Biotechnology Department (FaBiT), University of Bologna, Bologna, Italy
| | - Luciana Giardino
- Department of Veterinary Medical Sciences (DIMEVET), University of Bologna, Bologna, Italy.,IRET Foundation, Ozzano Emilia, Italy.,Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy
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47
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Ambrosini YM, Borcherding D, Kanthasamy A, Kim HJ, Willette AA, Jergens A, Allenspach K, Mochel JP. The Gut-Brain Axis in Neurodegenerative Diseases and Relevance of the Canine Model: A Review. Front Aging Neurosci 2019; 11:130. [PMID: 31275138 PMCID: PMC6591269 DOI: 10.3389/fnagi.2019.00130] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/16/2019] [Indexed: 12/13/2022] Open
Abstract
Identifying appropriate animal models is critical in developing translatable in vitro and in vivo systems for therapeutic drug development and investigating disease pathophysiology. These animal models should have direct biological and translational relevance to the underlying disease they are supposed to mimic. Aging dogs not only naturally develop a cognitive decline in many aspects including learning and memory deficits, but they also exhibit human-like individual variability in the aging process. Neurodegenerative processes that can be observed in both human and canine brains include the progressive accumulation of β-amyloid (Aβ) found as diffuse plaques in the prefrontal cortex (PFC), including the gyrus proreus (i.e., medial orbital PFC), as well as the hippocampus and the cerebral vasculature. Tau pathology, a marker of neurodegeneration and dementia progression, was also found in canine hippocampal synapses. Various epidemiological data show that human patients with neurodegenerative diseases have concurrent intestinal lesions, and histopathological changes in the gastrointestinal (GI) tract occurs decades before neurodegenerative changes. Gut microbiome alterations have also been reported in many neurodegenerative diseases including Alzheimer's (AD) and Parkinson's diseases, as well as inflammatory central nervous system (CNS) diseases. Interestingly, the dog gut microbiome more closely resembles human gut microbiome in composition and functional overlap compared to rodent models. This article reviews the physiology of the gut-brain axis (GBA) and its involvement with neurodegenerative diseases in humans. Additionally, we outline the advantages and weaknesses of current in vitro and in vivo models and discuss future research directions investigating major human neurodegenerative diseases such as AD and Parkinson's diseases using dogs.
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Affiliation(s)
- Yoko M. Ambrosini
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Dana Borcherding
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Anumantha Kanthasamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Hyun Jung Kim
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Auriel A. Willette
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
- Department of Food Science and Human Nutrition, College of Agriculture and Life Sciences, Iowa State University, Ames, IA, United States
| | - Albert Jergens
- Department of Veterinary Clinical Sciences, Iowa State University, Ames, IA, United States
| | - Karin Allenspach
- Department of Veterinary Clinical Sciences, Iowa State University, Ames, IA, United States
| | - Jonathan P. Mochel
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
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48
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Diverse Actions of Astrocytes in GABAergic Signaling. Int J Mol Sci 2019; 20:ijms20122964. [PMID: 31216630 PMCID: PMC6628243 DOI: 10.3390/ijms20122964] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/10/2019] [Accepted: 06/14/2019] [Indexed: 01/06/2023] Open
Abstract
An imbalance of excitatory and inhibitory neurotransmission leading to over excitation plays a crucial role in generating seizures, while enhancing GABAergic mechanisms are critical in terminating seizures. In recent years, it has been reported in many studies that astrocytes are deeply involved in synaptic transmission. Astrocytes form a critical component of the “tripartite” synapses by wrapping around the pre- and post-synaptic elements. From this location, astrocytes are known to greatly influence the dynamics of ions and transmitters in the synaptic cleft. Despite recent extensive research on excitatory tripartite synapses, inhibitory tripartite synapses have received less attention, even though they influence inhibitory synaptic transmission by affecting chloride and GABA concentration dynamics. In this review, we will discuss the diverse actions of astrocytic chloride and GABA homeostasis at GABAergic tripartite synapses. We will then consider the pathophysiological impacts of disturbed GABA homeostasis at the tripartite synapse.
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49
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Activity-Dependent Reconnection of Adult-Born Dentate Granule Cells in a Mouse Model of Frontotemporal Dementia. J Neurosci 2019; 39:5794-5815. [PMID: 31133559 DOI: 10.1523/jneurosci.2724-18.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 04/21/2019] [Accepted: 04/23/2019] [Indexed: 01/17/2023] Open
Abstract
Frontotemporal dementia (FTD) is characterized by neuronal loss in the frontal and temporal lobes of the brain. Here, we provide the first evidence of striking morphological alterations in dentate granule cells (DGCs) of FTD patients and in a mouse model of the disease, TauVLW mice. Taking advantage of the fact that the hippocampal dentate gyrus (DG) gives rise to newborn DGCs throughout the lifetime in rodents, we used RGB retroviruses to study the temporary course of these alterations in newborn DGCs of female TauVLW mice. In addition, retroviruses that encode either PSD95:GFP or Syn:GFP revealed striking alterations in the afferent and efferent connectivity of newborn TauVLW DGCs, and monosynaptic retrograde rabies virus tracing showed that these cells are disconnected from distal brain regions and local sources of excitatory innervation. However, the same cells exhibited a predominance of local inhibitory innervation. Accordingly, the expression of presynaptic and postsynaptic markers of inhibitory synapses was markedly increased in the DG of TauVLW mice and FTD patients. Moreover, an increased number of neuropeptide Y-positive interneurons in the DG correlated with a reduced number of activated egr-1+ DGCs in TauVLW mice. Finally, we tested the therapeutic potential of environmental enrichment and chemoactivation to reverse these alterations in mice. Both strategies reversed the morphological alterations of newborn DGCs and partially restored their connectivity in a mouse model of the disease. Moreover, our data point to remarkable morphological similarities between the DGCs of TauVLW mice and FTD patients.SIGNIFICANCE STATEMENT We show, for the first time to our knowledge, that the population of dentate granule cells is disconnected from other regions of the brain in the neurodegenerative disease frontotemporal dementia (FTD). These alterations were observed in FTD patients and in a mouse model of this disease. Moreover, we tested the therapeutic potential of two strategies, environmental enrichment and chemoactivation, to stimulate the activity of these neurons in mice. We found that some of the alterations were reversed by these therapeutic interventions.
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50
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Héja L, Simon Á, Szabó Z, Kardos J. Feedback adaptation of synaptic excitability via Glu:Na + symport driven astrocytic GABA and Gln release. Neuropharmacology 2019; 161:107629. [PMID: 31103619 DOI: 10.1016/j.neuropharm.2019.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/30/2019] [Accepted: 05/07/2019] [Indexed: 02/08/2023]
Abstract
Glutamatergic transmission composed of the arriving of action potential at the axon terminal, fast vesicular Glu release, postsynaptic Glu receptor activation, astrocytic Glu clearance and Glu→Gln shuttle is an abundantly investigated phenomenon. Despite its essential role, however, much less is known about the consequences of the mechanistic connotations of Glu:Na+ symport. Due to the coupled Na+ transport, Glu uptake results in significantly elevated intracellular astrocytic [Na+] that markedly alters the driving force of other Na+-coupled astrocytic transporters. The resulting GABA and Gln release by reverse transport through the respective GAT-3 and SNAT3 transporters help to re-establish the physiological Na+ homeostasis without ATP dissipation and consequently leads to enhanced tonic inhibition and replenishment of axonal glutamate pool. Here, we place this emerging astrocytic adjustment of synaptic excitability into the centre of future perspectives. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
- László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Ágnes Simon
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Zsolt Szabó
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary.
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