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O'Neill N, Stein TD, Olayinka OA, Empawi JA, Hu J, Tong T, Zhang X, Farrer LA. Cognitive resilience to Alzheimer's disease characterized by cell-type abundance. Alzheimers Dement 2024. [PMID: 39262221 DOI: 10.1002/alz.14187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 07/03/2024] [Accepted: 07/09/2024] [Indexed: 09/13/2024]
Abstract
INTRODUCTION The molecular basis of cognitive resilience (CR) among pathologically confirmed Alzheimer's disease (AD) cases is not well understood. METHODS Abundance of 13 cell types and neuronal subtypes in brain bulk RNA-seq data from the anterior caudate, dorsolateral prefrontal cortex (DLPFC), and posterior cingulate cortex (PCC) obtained from 434 AD cases, 318 cognitively resilient AD cases, and 188 controls in the Religious Orders Study and Rush Memory and Aging Project was estimated by deconvolution. RESULTS PVALB+ neuron abundance was negatively associated with cognitive status and tau pathology in the DLPFC and PCC (Padj < 0.001) and the most reduced neuronal subtype in AD cases compared to controls in DLPFC (Padj = 8.4 × 10-7) and PCC (Padj = 0.0015). We identified genome-wide significant association of neuron abundance with TMEM106B single nucleotide polymorphism rs13237518 in PCC (p = 6.08 × 10-12). rs13237518 was also associated with amyloid beta (p = 0.0085) and tangles (p = 0.0073). DISCUSSION High abundance of PVALB+ neurons may be a marker of CR. TMEM106B variants may influence CR independent of AD pathology. HIGHLIGHTS Neuron retention and a lack of astrocytosis are highly predictive of Alzheimer's disease (AD) resilience. PVALB+ GABAergic and RORB+ glutamatergic neurons are associated with cognitive status. A TMEM106B single nucleotide polymorphism is related to lower AD risk, higher neuron count, and increased AD pathology.
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Affiliation(s)
- Nicholas O'Neill
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Thor D Stein
- Department of Pathology and Laboratory Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
- VA Boston Healthcare Center, Boston, Massachusetts, USA
| | - Oluwatosin A Olayinka
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Jenny A Empawi
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Junming Hu
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Tong Tong
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Xiaoling Zhang
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, USA
| | - Lindsay A Farrer
- Bioinformatics Program, Boston University, Boston, Massachusetts, USA
- Department of Medicine (Section of Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, USA
- Department of Neurology, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- Department of Ophthalmology, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts, USA
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Barbour AJ, Gourmaud S, Lancaster E, Li X, Stewart DA, Hoag KF, Irwin DJ, Talos DM, Jensen FE. Seizures exacerbate excitatory: inhibitory imbalance in Alzheimer's disease and 5XFAD mice. Brain 2024; 147:2169-2184. [PMID: 38662500 PMCID: PMC11146435 DOI: 10.1093/brain/awae126] [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: 09/05/2023] [Revised: 03/02/2024] [Accepted: 03/24/2024] [Indexed: 05/14/2024] Open
Abstract
Approximately 22% of Alzheimer's disease (AD) patients suffer from seizures, and the co-occurrence of seizures and epileptiform activity exacerbates AD pathology and related cognitive deficits, suggesting that seizures may be a targetable component of AD progression. Given that alterations in neuronal excitatory:inhibitory (E:I) balance occur in epilepsy, we hypothesized that decreased markers of inhibition relative to those of excitation would be present in AD patients. We similarly hypothesized that in 5XFAD mice, the E:I imbalance would progress from an early stage (prodromal) to later symptomatic stages and be further exacerbated by pentylenetetrazol (PTZ) kindling. Post-mortem AD temporal cortical tissues from patients with or without seizure history were examined for changes in several markers of E:I balance, including levels of the inhibitory GABAA receptor, the sodium potassium chloride cotransporter 1 (NKCC1) and potassium chloride cotransporter 2 (KCC2) and the excitatory NMDA and AMPA type glutamate receptors. We performed patch-clamp electrophysiological recordings from CA1 neurons in hippocampal slices and examined the same markers of E:I balance in prodromal 5XFAD mice. We next examined 5XFAD mice at chronic stages, after PTZ or control protocols, and in response to chronic mTORC1 inhibitor rapamycin, administered following kindled seizures, for markers of E:I balance. We found that AD patients with comorbid seizures had worsened cognitive and functional scores and decreased GABAA receptor subunit expression, as well as increased NKCC1/KCC2 ratios, indicative of depolarizing GABA responses. Patch clamp recordings of prodromal 5XFAD CA1 neurons showed increased intrinsic excitability, along with decreased GABAergic inhibitory transmission and altered glutamatergic neurotransmission, indicating that E:I imbalance may occur in early disease stages. Furthermore, seizure induction in prodromal 5XFAD mice led to later dysregulation of NKCC1/KCC2 and a reduction in GluA2 AMPA glutamate receptor subunit expression, indicative of depolarizing GABA receptors and calcium permeable AMPA receptors. Finally, we found that chronic treatment with the mTORC1 inhibitor, rapamycin, at doses we have previously shown to attenuate seizure-induced amyloid-β pathology and cognitive deficits, could also reverse elevations of the NKCC1/KCC2 ratio in these mice. Our data demonstrate novel mechanisms of interaction between AD and epilepsy and indicate that targeting E:I balance, potentially with US Food and Drug Administration-approved mTOR inhibitors, hold therapeutic promise for AD patients with a seizure history.
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Affiliation(s)
- Aaron J Barbour
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah Gourmaud
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eunjoo Lancaster
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xiaofan Li
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David A Stewart
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Duke University School of Medicine, Durham, NC 27708, USA
| | - Keegan F Hoag
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David J Irwin
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Penn Frontotemporal Degeneration Center, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Delia M Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Frances E Jensen
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Gaur P, Bryois J, Calini D, Foo L, Hoozemans JJM, Malhotra D, Menon V. Single-nucleus and spatial transcriptomic profiling of human temporal cortex and white matter reveals novel associations with AD pathology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.23.590816. [PMID: 38712204 PMCID: PMC11071354 DOI: 10.1101/2024.04.23.590816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder with complex pathological manifestations and is the leading cause of cognitive decline and dementia in elderly individuals. A major goal in AD research is to identify new therapeutic pathways by studying the molecular and cellular changes in the disease, either downstream or upstream of the pathological hallmarks. In this study, we present a comprehensive investigation of cellular heterogeneity from the temporal cortex region of 40 individuals, comprising healthy donors and individuals with differing tau and amyloid burden. Using single-nucleus transcriptome analysis of 430,271 nuclei from both gray and white matter of these individuals, we identified cell type-specific subclusters in both neuronal and glial cell types with varying degrees of association with AD pathology. In particular, these associations are present in layer specific glutamatergic (excitatory) neuronal types, along with GABAergic (inhibitory) neurons and glial subtypes. These associations were observed in early as well as late pathological progression. We extended this analysis by performing multiplexed in situ hybridization using the CARTANA platform, capturing 155 genes in 13 individuals with varying levels of tau pathology. By modeling the spatial distribution of these genes and their associations with the pathology, we not only replicated key findings from our snRNA data analysis, but also identified a set of cell type-specific genes that show selective enrichment or depletion near pathological inclusions. Together, our findings allow us to prioritize specific cell types and pathways for targeted interventions at various stages of pathological progression in AD.
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Affiliation(s)
- Pallavi Gaur
- Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Irving Medical Center, NY, USA
| | - Julien Bryois
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, CH-4070, Basel, Switzerland
| | - Daniela Calini
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, CH-4070, Basel, Switzerland
| | - Lynette Foo
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, CH-4070, Basel, Switzerland
| | - Jeroen J M Hoozemans
- Department of Pathology, Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, Netherlands
| | - Dheeraj Malhotra
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center, CH-4070, Basel, Switzerland
- MS Research Unit, Biogen, Cambridge, MA, USA
| | - Vilas Menon
- Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Irving Medical Center, NY, USA
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Kamondi A, Grigg-Damberger M, Löscher W, Tanila H, Horvath AA. Epilepsy and epileptiform activity in late-onset Alzheimer disease: clinical and pathophysiological advances, gaps and conundrums. Nat Rev Neurol 2024; 20:162-182. [PMID: 38356056 DOI: 10.1038/s41582-024-00932-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2024] [Indexed: 02/16/2024]
Abstract
A growing body of evidence has demonstrated a link between Alzheimer disease (AD) and epilepsy. Late-onset epilepsy and epileptiform activity can precede cognitive deterioration in AD by years, and its presence has been shown to predict a faster disease course. In animal models of AD, amyloid and tau pathology are linked to cortical network hyperexcitability that precedes the first signs of memory decline. Thus, detection of epileptiform activity in AD has substantial clinical importance as a potential novel modifiable risk factor for dementia. In this Review, we summarize the epidemiological evidence for the complex bidirectional relationship between AD and epilepsy, examine the effect of epileptiform activity and seizures on cognition in people with AD, and discuss the precision medicine treatment strategies based on the latest research in human and animal models. Finally, we outline some of the unresolved questions of the field that should be addressed by rigorous research, including whether particular clinicopathological subtypes of AD have a stronger association with epilepsy, and the sequence of events between epileptiform activity and amyloid and tau pathology.
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Affiliation(s)
- Anita Kamondi
- National Institute of Mental Health, Neurology and Neurosurgery, Budapest, Hungary.
- Department of Neurology, Semmelweis University, Budapest, Hungary.
| | | | - Wolfgang Löscher
- Department of Experimental Otology of the ENT Clinics, Hannover Medical School, Hannover, Germany
| | - Heikki Tanila
- A. I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | - Andras Attila Horvath
- National Institute of Mental Health, Neurology and Neurosurgery, Budapest, Hungary
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
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Mohd Sahini SN, Mohd Nor Hazalin NA, Srikumar BN, Jayasingh Chellammal HS, Surindar Singh GK. Environmental enrichment improves cognitive function, learning, memory and anxiety-related behaviours in rodent models of dementia: Implications for future study. Neurobiol Learn Mem 2024; 208:107880. [PMID: 38103676 DOI: 10.1016/j.nlm.2023.107880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 11/27/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
Environmental enrichment (EE) is a process of brain stimulation by modifying the surroundings, for example, by changing the sensory, social, or physical conditions. Rodents have been used in such experimental strategies through exposure to diverse physical, social, and exploration conditions. The present study conducted an extensive analysis of the existing literature surrounding the impact of EE on dementia rodent models. The review emphasised the two principal aspects that are very closely related to dementia: cognitive function (learning and memory) as well as psychological factors (anxiety-related behaviours such as phobias and unrealistic worries). Also highlighted were the mechanisms involved in the rodent models of dementia showing EE effects. Two search engines, PubMed and Science Direct, were used for data collection using the following keywords: environmental enrichment, dementia, rodent model, cognitive performance, and anxiety-related behaviour. Fifty-five articles were chosen depending on the criteria for inclusion and exclusion. The rodent models with dementia demonstrated improved learning and memory in the form of hampered inflammatory responses, enhanced neuronal plasticity, and sustained neuronal activity. EE housing also prevented memory impairment through the prevention of amyloid beta (Aβ) seeding formation, an early stage of Aβ plaque formation. The rodents subjected to EE were observed to present increased exploratory activity and exert less anxiety-related behaviour, compared to those in standard housing. However, some studies have proposed that EE intervention through exercise would be too mild to counteract the anxiety-related behaviour and risk assessment behaviour deficits in the Alzheimer's disease rodent model. Future studies should be conducted on old-aged rodents and the duration of EE exposure that would elicit the greatest benefits since the existing studies have been conducted on a range of ages and EE durations. In summary, EE had a considerable effect on dementia rodent models, with the most evident being improved cognitive function.
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Affiliation(s)
- Siti Norhafizah Mohd Sahini
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Outpatient Pharmacy Department, Hospital Raja Permaisuri Bainun, 30450 Ipoh, Perak, Malaysia
| | - Nurul Aqmar Mohd Nor Hazalin
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Integrative Pharmacogenomics Institute (iPROMiSE), Level 7, FF3, Universiti Teknologi MARA, Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia
| | - Bettadapura N Srikumar
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bengaluru - 560029, India
| | - Hanish Singh Jayasingh Chellammal
- Department of Pharmacology and Pharmaceutical Chemistry, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Brain Degeneration and Therapeutics Group, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia
| | - Gurmeet Kaur Surindar Singh
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Brain Degeneration and Therapeutics Group, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia.
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Tan X, Ma H, Guo X, Mao M, Qiu L, Dai H, Dai Y, Cao J, Ma H, Sun J. Disinhibition of hippocampal parvalbumin interneurons on pyramidal neurons participates in LPS-induced cognitive dysfunction. Neurosci Lett 2024; 821:137614. [PMID: 38159880 DOI: 10.1016/j.neulet.2023.137614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 11/12/2023] [Accepted: 12/22/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND The vulnerability of hippocampal pyramidal (PY) neurons played a key role in the onset of cognitive impairment. Multiple researches revealed that neuroinflammation together with microglia activation and parvalbumin (PV) interneurons participated in the pathogenesis of cognitive dysfunction. However, the underlying mechanism was still unclear. This study aimed to determine whether microglia activation would induce PV interneurons impairment and PY neurons disinhibition, and as a result, promote cognitive dysfunction after lipopolysaccharide (LPS) challenge. METHODS Male C57BL/6J mice were injected with LPS to establish systemic inflammation model, and animal behavioral tests were performed. For chemogenetics, the virus was injected bilaterally into the CA1 region. Clozapine N-Oxide (CNO) was used to activate the PV interneurons. Whole-cell patch clamp recording was applied to detect spontaneous inhibitory post synaptic current (sIPSC) and spontaneous excitatory post synaptic current (sEPSC) of PY neurons in the CA1 region. RESULTS LPS induced hippocampal dependent memory impairment, which was accompanied with microglia activation. Meanwhile, PV protein level in hippocampus were decreased, and IPSCs of PY neurons in the CA1 were also suppressed. Minocycline reversed all the above changes. In addition, rescuing PV function with CNO improved memory impairment, sIPSCs of PY neurons and perisomatic PV boutons around PY neurons without affecting microglia activation. CONCLUSION Disinhibition of hippocampal parvalbumin interneurons on pyramidal neurons participates in LPS-induced cognitive dysfunction.
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Affiliation(s)
- Xiaoxiang Tan
- Department of Anesthesiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Hongyu Ma
- Department of Physiology, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Xinqi Guo
- Department of Physiology, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Meng Mao
- Department of Anesthesiology, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Lili Qiu
- Department of Anesthesiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Hongyu Dai
- Department of Anesthesiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Yuchen Dai
- Department of Anesthesiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Jinyuan Cao
- Department of Anesthesiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Huijie Ma
- Department of Physiology, Hebei Medical University, Shijiazhuang, Hebei Province, China.
| | - Jie Sun
- Department of Anesthesiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu Province, China.
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Hijazi S, Smit AB, van Kesteren RE. Fast-spiking parvalbumin-positive interneurons in brain physiology and Alzheimer's disease. Mol Psychiatry 2023; 28:4954-4967. [PMID: 37419975 PMCID: PMC11041664 DOI: 10.1038/s41380-023-02168-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/26/2023] [Accepted: 06/26/2023] [Indexed: 07/09/2023]
Abstract
Fast-spiking parvalbumin (PV) interneurons are inhibitory interneurons with unique morphological and functional properties that allow them to precisely control local circuitry, brain networks and memory processing. Since the discovery in 1987 that PV is expressed in a subset of fast-spiking GABAergic inhibitory neurons, our knowledge of the complex molecular and physiological properties of these cells has been expanding. In this review, we highlight the specific properties of PV neurons that allow them to fire at high frequency and with high reliability, enabling them to control network oscillations and shape the encoding, consolidation and retrieval of memories. We next discuss multiple studies reporting PV neuron impairment as a critical step in neuronal network dysfunction and cognitive decline in mouse models of Alzheimer's disease (AD). Finally, we propose potential mechanisms underlying PV neuron dysfunction in AD and we argue that early changes in PV neuron activity could be a causal step in AD-associated network and memory impairment and a significant contributor to disease pathogenesis.
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Affiliation(s)
- Sara Hijazi
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, UK
| | - August B Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 HV, Amsterdam, The Netherlands
| | - Ronald E van Kesteren
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 HV, Amsterdam, The Netherlands.
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Chen KS, Noureldein MH, Rigan DM, Hayes JM, Savelieff MG, Feldman EL. Regional interneuron transcriptional changes reveal pathologic markers of disease progression in a mouse model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.01.565165. [PMID: 37961679 PMCID: PMC10635060 DOI: 10.1101/2023.11.01.565165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder and leading cause of dementia, characterized by neuronal and synapse loss, amyloid-β and tau protein aggregates, and a multifactorial pathology involving neuroinflammation, vascular dysfunction, and disrupted metabolism. Additionally, there is growing evidence of imbalance between neuronal excitation and inhibition in the AD brain secondary to dysfunction of parvalbumin (PV)- and somatostatin (SST)-positive interneurons, which differentially modulate neuronal activity. Importantly, impaired interneuron activity in AD may occur upstream of amyloid-β pathology rendering it a potential therapeutic target. To determine the underlying pathologic processes involved in interneuron dysfunction, we spatially profiled the brain transcriptome of the 5XFAD AD mouse model versus controls, across four brain regions, dentate gyrus, hippocampal CA1 and CA3, and cortex, at early-stage (12 weeks-of-age) and late-stage (30 weeks-of-age) disease. Global comparison of differentially expressed genes (DEGs) followed by enrichment analysis of 5XFAD versus control highlighted various biological pathways related to RNA and protein processing, transport, and clearance in early-stage disease and neurodegeneration pathways at late-stage disease. Early-stage DEGs examination found shared, e.g ., RNA and protein biology, and distinct, e.g ., N-glycan biosynthesis, pathways enriched in PV-versus somatostatin SST-positive interneurons and in excitatory neurons, which expressed neurodegenerative and axon- and synapse-related pathways. At late-stage disease, PV-positive interneurons featured cancer and cancer signaling pathways along with neuronal and synapse pathways, whereas SST-positive interneurons showcased glycan biosynthesis and various infection pathways. Late-state excitatory neurons were primarily characterized by neurodegenerative pathways. These fine-grained transcriptomic profiles for PV- and SST-positive interneurons in a time- and spatial-dependent manner offer new insight into potential AD pathophysiology and therapeutic targets.
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Zhang NK, Zhang SK, Zhang LI, Tao HW, Zhang GW. Sensory processing deficits and related cortical pathological changes in Alzheimer's disease. Front Aging Neurosci 2023; 15:1213379. [PMID: 37649717 PMCID: PMC10464619 DOI: 10.3389/fnagi.2023.1213379] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 07/24/2023] [Indexed: 09/01/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder primarily affecting cognitive functions. However, sensory deficits in AD start to draw attention due to their high prevalence and early onsets which suggest that they could potentially serve as diagnostic biomarkers and even contribute to the disease progression. This literature review examines the sensory deficits and cortical pathological changes observed in visual, auditory, olfactory, and somatosensory systems in AD patients, as well as in various AD animal models. Sensory deficits may emerge at the early stages of AD, or even precede the cognitive decline, which is accompanied by cortical pathological changes including amyloid-beta deposition, tauopathy, gliosis, and alterations in neuronal excitability, synaptic inputs, and functional plasticity. Notably, these changes are more pronounced in sensory association areas and superficial cortical layers, which may explain the relative preservation of basic sensory functions but early display of deficits of higher sensory functions. We propose that sensory impairment and the progression of AD may establish a cyclical relationship that mutually perpetuates each condition. This review highlights the significance of sensory deficits with or without cortical pathological changes in AD and emphasizes the need for further research to develop reliable early detection and intervention through sensory systems.
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Affiliation(s)
- Nicole K. Zhang
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Selena K. Zhang
- Biomedical Engineering Program, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Li I. Zhang
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- Department of Physiology & Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Huizhong W. Tao
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- Department of Physiology & Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Guang-Wei Zhang
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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Garcia-Casas P, Rossini M, Filadi R, Pizzo P. Mitochondrial Ca 2+ signaling and Alzheimer's disease: Too much or too little? Cell Calcium 2023; 113:102757. [PMID: 37192560 DOI: 10.1016/j.ceca.2023.102757] [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: 02/28/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/18/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease, caused by poorly known pathogenic mechanisms and aggravated by delayed therapeutic intervention, that still lacks an effective cure. However, it is clear that some important neurophysiological processes are altered years before the onset of clinical symptoms, offering the possibility of identifying biological targets useful for implementation of new therapies. Of note, evidence has been provided suggesting that mitochondria, pivotal organelles in sustaining neuronal energy demand and modulating synaptic activity, are dysfunctional in AD samples. In particular, alterations in mitochondrial Ca2+ signaling have been proposed as causal events for neurodegeneration, although the exact outcomes and molecular mechanisms of these defects, as well as their longitudinal progression, are not always clear. Here, we discuss the importance of a correct mitochondrial Ca2+ handling for neuronal physiology and summarize the latest findings on dysfunctional mitochondrial Ca2+ pathways in AD, analysing possible consequences contributing to the neurodegeneration that characterizes the disease.
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Affiliation(s)
- Paloma Garcia-Casas
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Department of Biochemistry and Molecular Biology and Physiology, School of Medicine, University of Valladolid, 47003 Valladolid, Spain
| | - Michela Rossini
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
| | - Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy.
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy; Study Centre for Neurodegeneration (CESNE), University of Padova, 35131 Padua, Italy.
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Varte V, Munkelwitz JW, Rincon-Limas DE. Insights from Drosophila on Aβ- and tau-induced mitochondrial dysfunction: mechanisms and tools. Front Neurosci 2023; 17:1184080. [PMID: 37139514 PMCID: PMC10150963 DOI: 10.3389/fnins.2023.1184080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 03/31/2023] [Indexed: 05/05/2023] Open
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative dementia in older adults worldwide. Sadly, there are no disease-modifying therapies available for treatment due to the multifactorial complexity of the disease. AD is pathologically characterized by extracellular deposition of amyloid beta (Aβ) and intracellular neurofibrillary tangles composed of hyperphosphorylated tau. Increasing evidence suggest that Aβ also accumulates intracellularly, which may contribute to the pathological mitochondrial dysfunction observed in AD. According with the mitochondrial cascade hypothesis, mitochondrial dysfunction precedes clinical decline and thus targeting mitochondria may result in new therapeutic strategies. Unfortunately, the precise mechanisms connecting mitochondrial dysfunction with AD are largely unknown. In this review, we will discuss how the fruit fly Drosophila melanogaster is contributing to answer mechanistic questions in the field, from mitochondrial oxidative stress and calcium dysregulation to mitophagy and mitochondrial fusion and fission. In particular, we will highlight specific mitochondrial insults caused by Aβ and tau in transgenic flies and will also discuss a variety of genetic tools and sensors available to study mitochondrial biology in this flexible organism. Areas of opportunity and future directions will be also considered.
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Affiliation(s)
- Vanlalrinchhani Varte
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, United States
| | - Jeremy W. Munkelwitz
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, United States
| | - Diego E. Rincon-Limas
- Department of Neurology, McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, United States
- Department of Neuroscience, University of Florida, Gainesville, FL, United States
- Genetics Institute, University of Florida, Gainesville, FL, United States
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12
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Perez SM, Boley AM, McCoy AM, Lodge DJ. Aberrant Dopamine System Function in the Ferrous Amyloid Buthionine (FAB) Rat Model of Alzheimer's Disease. Int J Mol Sci 2023; 24:7196. [PMID: 37108357 PMCID: PMC10138591 DOI: 10.3390/ijms24087196] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/06/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Antipsychotics increase the risk of death in elderly patients with Alzheimer's disease (AD). Thus, there is an immediate need for novel therapies to treat comorbid psychosis in AD. Psychosis has been attributed to a dysregulation of the dopamine system and is associated with aberrant regulation by the hippocampus. Given that the hippocampus is a key site of pathology in AD, we posit that aberrant regulation of the dopamine system may contribute to comorbid psychosis in AD. A ferrous amyloid buthionine (FAB) rodent model was used to model a sporadic form of AD. FAB rats displayed functional hippocampal alterations, which were accompanied by decreases in spontaneous, low-frequency oscillations and increases in the firing rates of putative pyramidal neurons. Additionally, FAB rats exhibited increases in dopamine neuron population activity and augmented responses to the locomotor-inducing effects of MK-801, as is consistent with rodent models of psychosis-like symptomatology. Further, working memory deficits in the Y-maze, consistent with an AD-like phenotype, were observed in FAB rats. These data suggest that the aberrant hippocampal activity observed in AD may contribute to dopamine-dependent psychosis, and that the FAB model may be useful for the investigation of comorbid psychosis related to AD. Understanding the pathophysiology that leads to comorbid psychosis in AD will ultimately lead to the discovery of novel targets for the treatment of this disease.
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Affiliation(s)
- Stephanie M. Perez
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, TX 78229, USA; (A.M.B.); (D.J.L.)
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, TX 78229, USA
| | - Angela M. Boley
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, TX 78229, USA; (A.M.B.); (D.J.L.)
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, TX 78229, USA
| | - Alexandra M. McCoy
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, TX 78229, USA; (A.M.B.); (D.J.L.)
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, TX 78229, USA
| | - Daniel J. Lodge
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, TX 78229, USA; (A.M.B.); (D.J.L.)
- South Texas Veterans Health Care System, Audie L. Murphy Division, San Antonio, TX 78229, USA
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13
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Zhi W, Yong Z, Ma L, He S, Guo Z, Zhao X, Hu X, Wang L. 900 MHz electromagnetic field exposure relieved AD-like symptoms on APP/PS1 mice: A potential non-invasive strategy for AD treatment. Biochem Biophys Res Commun 2023; 658:97-106. [PMID: 37030070 DOI: 10.1016/j.bbrc.2023.03.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/15/2023] [Accepted: 03/31/2023] [Indexed: 04/04/2023]
Abstract
BACKGROUND Evidence shows that microwaves radiation may have various biological effects on central nervous system. Role of electromagnetic fields in neurodegenerative diseases, especially AD, has been widely studied, but results of these studies are inconsistent. Therefore, the above effects were verified again and the mechanism was preliminarily discussed. METHODS Amyloid precursor protein (APP/PS1) and WT mice were exposed to long-term microwave radiation for 270 days (900 MHz, SAR: 0.25-1.055 W/kg, 2 h/day, alternately), and related indices were assessed at 90, 180 and 270 days. Cognition was evaluated by Morris water maze, Y maze and new object recognition tests. Congo red staining, immunohistochemistry and ELISA were used to analyze Aβ plaques, Aβ40 and Aβ42 content. Differentially expressed proteins in hippocampus between microwave-exposed and unexposed AD mice were identified by proteomics. RESULTS Spatial and working memory was improved in AD mice after long-term 900 MHz microwave exposure compared with after sham exposure. Microwave radiation (900 MHz) for 180 or 270 days did not induce Aβ plaque formation in WT mice but inhibited Aβ accumulation in the cerebral cortex and hippocampus in 2- and 5-month-old APP/PS1 mice. This effect mainly occurred in the late stage of the disease and may have been attributed to downregulation of apolipoprotein family member and SNCA expression and excitatory/inhibitory neurotransmitter rebalance in the hippocampus. CONCLUSIONS The present results indicated that long-term microwave radiation can retard AD development and exert a beneficial effect against AD, suggesting that 900 MHz microwave exposure may be a potential therapy for AD.
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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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Tan X, Wang J, Yao J, Yuan J, Dai Y, Sun M, Zhang T, Yang J, Cai W, Qiu L, Sun J. Microglia participate in postoperative cognitive dysfunction by mediating the loss of inhibitory synapse through the complement pathway. Neurosci Lett 2023; 796:137049. [PMID: 36608926 DOI: 10.1016/j.neulet.2023.137049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 12/13/2022] [Accepted: 01/01/2023] [Indexed: 01/05/2023]
Abstract
BACKGROUND Elderly patients after surgery are prone to cognitive decline known as postoperative cognitive dysfunction (POCD). Several studies have shown that the microglial activation and the increase of complement protein expression in hippocampus induced by surgery may be related to the pathogenesis of POCD. The purpose of this study was to determine whether microglia and complement system were involved in cognitive dysfunction in aged mice. METHODS The POCD model was established by exploratory laparotomy in 15-month-old male C57BL/6J mice and animal behavioral tests were performed to test hippocampal-dependent memory capacity. Minocycline was used to suppress the activation of microglia, and complement 3 receptor inhibitor was used to suppress the association between microglia and complement 3. Western blot and immunofluorescence were used to detect the microglial activation, complement protein, and synaptic protein expressions. RESULTS Operation induced hippocampal-dependent memory impairment (P < 0.01), which was accompanied by microglial activation (P < 0.01). There was also a significant reduction in inhibitory synaptic protein expression in the hippocampus of mice in the surgery group (P < 0.01). However, minocycline, a microglia inhibitor, rescued all the above changes. In addition, C3RI intervention inhibited the phagocytosis of inhibitory synapses by microglia (P < 0.05) and improved the cognitive function of mice (P < 0.01). CONCLUSION Microglia participate in postoperative cognitive dysfunction by mediating inhibitory synaptic loss through the complement pathway.
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Affiliation(s)
- Xiaoxiang Tan
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Jiajia Wang
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Juan Yao
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Jing Yuan
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Yuchen Dai
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Menghan Sun
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Tianhao Zhang
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Jiaojiao Yang
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Wenlan Cai
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China
| | - Lili Qiu
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China.
| | - Jie Sun
- Department of Anesthesiology, Surgery and Pain Management, Zhongda Hospital, the School of Medicine, Southeast University, Nanjing, Jiangsu Province, China.
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16
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Tan Z, Garduño BM, Aburto PF, Chen L, Ha N, Cogram P, Holmes TC, Xu X. Cognitively impaired aged Octodon degus recapitulate major neuropathological features of sporadic Alzheimer's disease. Acta Neuropathol Commun 2022; 10:182. [PMID: 36529803 PMCID: PMC9761982 DOI: 10.1186/s40478-022-01481-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/20/2022] [Indexed: 12/23/2022] Open
Abstract
The long-lived Chilean rodent (Octodon degus) has been reported to show spontaneous age-dependent neuropathology and cognitive impairments similar to those observed in human AD. However, the handful of published papers on degus of differing genetic backgrounds yield inconsistent findings about sporadic AD-like pathological features, with notably differing results between lab in-bred degus versus outbred degus. This motivates more extensive characterization of spontaneously occurring AD-like pathology and behavior in degus. In the present study, we show AD-like neuropathological markers in the form of amyloid deposits and tau abnormalities in a cognitively impaired subset of aged outbred degus. Compared to the aged degus that show normal burrowing behavior, the age-matched degus with burrowing behavior deficits correlatively exhibit detectable human AD-like Aβ deposits and tau neuropathology, along with neuroinflammatory markers that include enhanced microglial activation and higher numbers of reactive astrocytes in the brain. This subset of cognitively impaired aged degus also exhibits cerebral amyloid angiopathy and tauopathy. We find robust neurodegenerative features in behaviorally deficient aged degus, including hippocampal neuronal loss, altered parvalbumin and perineuronal net staining in the cortex, and increased c-Fos neuronal activation in the cortex that is consistent with the neural circuit hyperactivity reported in human AD patients. By focusing on the subset of aged degus that show AD-like behavioral deficits and correlative neuropathology, our findings establish outbred degus as a natural model of sporadic AD and demonstrate the potential importance of wild-type outbred genetic backgrounds for AD pathogenesis.
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Affiliation(s)
- Zhiqun Tan
- Department Anatomy and Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
- The Center for Neural Circuit Mapping, University of California, Irvine, CA, 92697, USA
| | - B Maximiliano Garduño
- Department Anatomy and Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Pedro Fernández Aburto
- Institute of Ecology and Biodiversity, Department of Ecological Sciences, Faculty of Sciences, University of Chile, Santiago, Chile
| | - Lujia Chen
- Department Anatomy and Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Nicole Ha
- Department Anatomy and Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Patricia Cogram
- Institute of Ecology and Biodiversity, Department of Ecological Sciences, Faculty of Sciences, University of Chile, Santiago, Chile
- The Center for Neural Circuit Mapping, University of California, Irvine, CA, 92697, USA
| | - Todd C Holmes
- Department Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
- The Center for Neural Circuit Mapping, University of California, Irvine, CA, 92697, USA
| | - Xiangmin Xu
- Department Anatomy and Neurobiology, School of Medicine, University of California, Irvine, CA, 92697, USA.
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA.
- The Center for Neural Circuit Mapping, University of California, Irvine, CA, 92697, USA.
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Li H, Zhao J, Lai L, Xia Y, Wan C, Wei S, Liang J, Chen Y, Xu N. Loss of SST and PV Positive Interneurons in the Ventral Hippocampus Results in Anxiety-like Behavior in 5xFAD Mice. Neurobiol Aging 2022; 117:165-178. [DOI: 10.1016/j.neurobiolaging.2022.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 05/13/2022] [Accepted: 05/28/2022] [Indexed: 10/18/2022]
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18
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Vasilev DS, Dubrovskaya NМ, Tumanova NL, Nalivaeva NN. Analysis of Expression of the Amyloid-Degrading Enzyme Neprilysin in Brain Structures of 5xFAD Transgenic Mice. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022010173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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19
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Jeong WH, Kim WI, Lee JW, Park HK, Song MK, Choi IS, Han JY. Modulation of Long-Term Potentiation by Gamma Frequency Transcranial Alternating Current Stimulation in Transgenic Mouse Models of Alzheimer's Disease. Brain Sci 2021; 11:1532. [PMID: 34827531 PMCID: PMC8615498 DOI: 10.3390/brainsci11111532] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/17/2021] [Accepted: 11/17/2021] [Indexed: 11/16/2022] Open
Abstract
Transcranial alternating current stimulation (tACS) is a neuromodulation procedure that is currently studied for the purpose of improving cognitive function in various diseases. A few studies have shown positive effects of tACS in Alzheimer's disease (AD). However, the mechanism underlying tACS has not been established. The purpose of this study was to investigate the mechanism of tACS in five familial AD mutation (5xFAD) mouse models. We prepared twenty 4-month-old mice and divided them into four groups: wild-type mice without stimulation (WT-NT group), wild-type mice with tACS (WT-T group), 5xFAD mice without stimulation (AD-NT group), and 5xFAD mice with tACS (AD-T group). The protocol implemented was as follows: gamma frequency 200 μA over the bilateral frontal lobe for 20 min over 2 weeks. The following tests were conducted: excitatory postsynaptic potential (EPSP) recording, Western blot analysis (cyclic AMP response element-binding (CREB) proteins, phosphorylated CREB proteins, brain-derived neurotrophic factor, and parvalbumin) to examine the synaptic plasticity. The EPSP was remarkably increased in the AD-T group compared with in the AD-NT group. In the Western blot analysis, the differences among the groups were not significant. Hence, tACS can affect the long-lasting enhancement of synaptic transmission in mice models of AD.
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Affiliation(s)
- Won-Hyeong Jeong
- Department of Physical & Rehabilitation Medicine, Chonnam National University Hospital, Gwangju City 61469, Korea; (W.-H.J.); (W.-I.K.); (J.-W.L.); (H.-K.P.); (I.-S.C.)
| | - Wang-In Kim
- Department of Physical & Rehabilitation Medicine, Chonnam National University Hospital, Gwangju City 61469, Korea; (W.-H.J.); (W.-I.K.); (J.-W.L.); (H.-K.P.); (I.-S.C.)
| | - Jin-Won Lee
- Department of Physical & Rehabilitation Medicine, Chonnam National University Hospital, Gwangju City 61469, Korea; (W.-H.J.); (W.-I.K.); (J.-W.L.); (H.-K.P.); (I.-S.C.)
| | - Hyeng-Kyu Park
- Department of Physical & Rehabilitation Medicine, Chonnam National University Hospital, Gwangju City 61469, Korea; (W.-H.J.); (W.-I.K.); (J.-W.L.); (H.-K.P.); (I.-S.C.)
| | - Min-Keun Song
- Department of Physical & Rehabilitation Medicine, Regional Cardiocerebrovascular Center, Center for Aging and Geriatrics, Chonnam National University Medical School & Hospital, Gwangju City 61469, Korea;
| | - In-Sung Choi
- Department of Physical & Rehabilitation Medicine, Chonnam National University Hospital, Gwangju City 61469, Korea; (W.-H.J.); (W.-I.K.); (J.-W.L.); (H.-K.P.); (I.-S.C.)
| | - Jae-Young Han
- Department of Physical & Rehabilitation Medicine, Regional Cardiocerebrovascular Center, Center for Aging and Geriatrics, Chonnam National University Medical School & Hospital, Gwangju City 61469, Korea;
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20
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SOCS1 Mediates Berberine-Induced Amelioration of Microglial Activated States in N9 Microglia Exposed to β Amyloid. BIOMED RESEARCH INTERNATIONAL 2021; 2021:9311855. [PMID: 34778460 PMCID: PMC8589517 DOI: 10.1155/2021/9311855] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 09/24/2021] [Accepted: 10/25/2021] [Indexed: 01/26/2023]
Abstract
Attenuating β amyloid- (Aβ-) induced microglial activation is considered to be effective in treating Alzheimer's disease (AD). Berberine (BBR) can reduce microglial activation in Aβ-treated microglial cells; the mechanism, however, is still illusive. Silencing of cytokine signaling factor 1 (SOCS1) is the primary regulator of many cytokines involved in immune reactions, whose upregulation can reverse the activation of microglial cells. Microglia could be activated into two different statuses, classic activated state (M1 state) and alternative activated state (M2 state), and M1 state is harmful, but M2 is beneficial. In the present study, N9 microglial cells were exposed to Aβ to imitate microglial activation in AD. And Western blot and immunocytochemistry were taken to observe inducible nitric oxide synthase (iNOS), Arginase-1 (Arg-1), and SOCS1 expressions, and the enzyme-linked immunosorbent assay (ELISA) was used to measure inflammatory and neurotrophic factor release. Compared with the normal cultured control cells, Aβ exposure markedly increased the level of microglial M1 state markers (P < 0.05), including iNOS protein expression, tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 releases, and BBR administration upregulated SOSC1 expression and the level of microglial M2 state markers (P < 0.05), such as Arg-1 expression, brain-derived neurotrophic factor (BDNF), and glial cell-derived neurotrophic factor (GDNF) releases, downregulating the SOCS1 expression by using siRNA, however, significantly reversed the BBR-induced effects on microglial M1 and M2 state markers and SOCS1 expression (P < 0.05). These findings indicated that BBR can inhibit Aβ-induced microglial activation via modulating the microglial M1/M2 activated state, and SOCS1 mediates the process.
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21
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Crapser JD, Arreola MA, Tsourmas KI, Green KN. Microglia as hackers of the matrix: sculpting synapses and the extracellular space. Cell Mol Immunol 2021; 18:2472-2488. [PMID: 34413489 PMCID: PMC8546068 DOI: 10.1038/s41423-021-00751-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/26/2021] [Indexed: 02/08/2023] Open
Abstract
Microglia shape the synaptic environment in health and disease, but synapses do not exist in a vacuum. Instead, pre- and postsynaptic terminals are surrounded by extracellular matrix (ECM), which together with glia comprise the four elements of the contemporary tetrapartite synapse model. While research in this area is still just beginning, accumulating evidence points toward a novel role for microglia in regulating the ECM during normal brain homeostasis, and such processes may, in turn, become dysfunctional in disease. As it relates to synapses, microglia are reported to modify the perisynaptic matrix, which is the diffuse matrix that surrounds dendritic and axonal terminals, as well as perineuronal nets (PNNs), specialized reticular formations of compact ECM that enwrap neuronal subsets and stabilize proximal synapses. The interconnected relationship between synapses and the ECM in which they are embedded suggests that alterations in one structure necessarily affect the dynamics of the other, and microglia may need to sculpt the matrix to modify the synapses within. Here, we provide an overview of the microglial regulation of synapses, perisynaptic matrix, and PNNs, propose candidate mechanisms by which these structures may be modified, and present the implications of such modifications in normal brain homeostasis and in disease.
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Affiliation(s)
- Joshua D. Crapser
- grid.266093.80000 0001 0668 7243Department of Neurobiology and Behavior, University of California, Irvine, CA USA
| | - Miguel A. Arreola
- grid.266093.80000 0001 0668 7243Department of Neurobiology and Behavior, University of California, Irvine, CA USA
| | - Kate I. Tsourmas
- grid.266093.80000 0001 0668 7243Department of Neurobiology and Behavior, University of California, Irvine, CA USA
| | - Kim N. Green
- grid.266093.80000 0001 0668 7243Department of Neurobiology and Behavior, University of California, Irvine, CA USA
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22
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Giesers NK, Wirths O. Loss of Hippocampal Calretinin and Parvalbumin Interneurons in the 5XFAD Mouse Model of Alzheimer's Disease. ASN Neuro 2021; 12:1759091420925356. [PMID: 32423230 PMCID: PMC7238451 DOI: 10.1177/1759091420925356] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The deposition of amyloid-β peptides in the form of extracellular plaques
and neuronal degeneration belong to the hallmark features of
Alzheimer’s disease (AD). In addition, impaired calcium homeostasis
and altered levels in calcium-binding proteins seem to be associated
with the disease process. In this study, calretinin- (CR) and
parvalbumin- (PV) positive gamma-aminobutyric acid-producing
(GABAergic) interneurons were quantified in different hippocampal
subfields of 12-month-old wild-type mice, as well as in the transgenic
AD mouse models 5XFAD and Tg4-42. While, in comparison with wild-type
mice, CR-positive interneurons were mainly reduced in the CA1 and
CA2/3 regions in plaque-bearing 5XFAD mice, PV-positive interneurons
were reduced in all analyzed subfields including the dentate gyrus. No
reduction in CR- and PV-positive interneuron numbers was detected in
the non-plaque-forming Tg4-42 mouse, although this model has been
previously demonstrated to harbor a massive loss of CA1 pyramidal
neurons. These results provide information about hippocampal
interneuron numbers in two relevant AD mouse models, suggesting that
interneuron loss in this brain region may be related to extracellular
amyloid burden.
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Affiliation(s)
- Naomi K Giesers
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
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23
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Uddin O, Arakawa K, Raver C, Garagusi B, Keller A. Patterns of cognitive decline and somatosensory processing in a mouse model of amyloid accumulation. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2021; 10:100076. [PMID: 34820549 PMCID: PMC8599510 DOI: 10.1016/j.ynpai.2021.100076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/28/2021] [Accepted: 11/01/2021] [Indexed: 01/13/2023]
Abstract
Despite copious amyloid plaques, 5XFAD mice show modest signs of cognitive decline. At ages 2 to 13 months old 5XFAD mice show no signs of sensory or pain dysfunctions. 5XFAD mice may not be a valid model for pain abnormalities in the context of AD.
Pain and cognitive decline increase with age. In particular, there is a troubling relationship between dementia and pain, with some studies showing higher prevalence and inadequate treatment of pain in this population. Alzheimer’s disease (AD) is one of the most common causes of dementia in older adults. Amyloid plaques are a hallmark of AD. The downstream processes these plaques promote are believed to affect neuronal and glial health and activity. There is a need to better understand how the neuropathological changes of AD shape neural activity and pain sensitivity. Here, we use the 5XFAD mouse model, in which dense amyloid accumulations occur at early ages, and in which previous studies reported signs of cognitive decline. We hypothesized that 5XFAD mice develop sensory and pain processing dysfunctions. Although amyloid burden was high throughout the brain, including in regions involved with sensory processing, we identified no functionally significant differences in reflexive or spontaneous signs of pain. Furthermore, expected signs of cognitive decline were modest; a finding consistent with variable results in the literature. These data suggest that models recapitulating other pathological features of Alzheimer’s disease might be better suited to studying differences in pain perception in this disease.
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Affiliation(s)
- Olivia Uddin
- Department of Anatomy and Neurobiology, Program in Neuroscience, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD 21201, United States
| | - Keiko Arakawa
- Department of Anatomy and Neurobiology, Program in Neuroscience, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD 21201, United States
| | - Charles Raver
- Department of Anatomy and Neurobiology, Program in Neuroscience, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD 21201, United States
| | - Brendon Garagusi
- Department of Anatomy and Neurobiology, Program in Neuroscience, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD 21201, United States
| | - Asaf Keller
- Department of Anatomy and Neurobiology, Program in Neuroscience, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD 21201, United States
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The interplay of neurovasculature and adult hippocampal neurogenesis. Neurosci Lett 2021; 760:136071. [PMID: 34147540 DOI: 10.1016/j.neulet.2021.136071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 05/06/2021] [Accepted: 06/15/2021] [Indexed: 01/14/2023]
Abstract
The subgranular zone of the dentate gyrus provides a local microenvironment (niche) for neural stem cells. In the adult brain, it has been established that the vascular compartment of such niches has a significant role in regulating adult hippocampal neurogenesis. More recently, evidence showed that neurovascular coupling, the relationship between blood flow and neuronal activity, also regulates hippocampal neurogenesis. Here, we review the most recent articles on addressing the intricate relationship between neurovasculature and adult hippocampal neurogenesis and a novel pathway where functional hyperemia enhances hippocampal neurogenesis. In the end, we have further reviewed recent research showing that impaired neurovascular coupling may cause declined neurogenesis and contribute to brain damage in neurodegenerative diseases.
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Prince SM, Paulson AL, Jeong N, Zhang L, Amigues S, Singer AC. Alzheimer's pathology causes impaired inhibitory connections and reactivation of spatial codes during spatial navigation. Cell Rep 2021; 35:109008. [PMID: 33882308 PMCID: PMC8139125 DOI: 10.1016/j.celrep.2021.109008] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 01/12/2021] [Accepted: 03/25/2021] [Indexed: 12/21/2022] Open
Abstract
Synapse loss and altered synaptic strength are thought to underlie cognitive impairment in Alzheimer’s disease (AD) by disrupting neural activity essential for memory. While synaptic dysfunction in AD has been well characterized in anesthetized animals and in vitro, it remains unknown how synaptic transmission is altered during behavior. By measuring synaptic efficacy as mice navigate in a virtual reality task, we find deficits in interneuron connection strength onto pyramidal cells in hippocampal CA1 in the 5XFAD mouse model of AD. These inhibitory synaptic deficits are most pronounced during sharp-wave ripples, network oscillations important for memory that require inhibition. Indeed, 5XFAD mice exhibit fewer and shorter sharp-wave ripples with impaired place cell reactivation. By showing inhibitory synaptic dysfunction in 5XFAD mice during spatial navigation behavior and suggesting a synaptic mechanism underlying deficits in network activity essential for memory, this work bridges the gap between synaptic and neural activity deficits in AD. Prince et al. find impaired inhibitory synapses, sharp-wave ripples, and place cell reactivation during behavior in a mouse model of Alzheimer’s disease. These results link synaptic deficits in Alzheimer’s disease to dysfunction of neural activity essential for memory.
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Affiliation(s)
- Stephanie M Prince
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA 30332, USA; Neuroscience Graduate Program, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, GA, 30322, USA
| | - Abigail L Paulson
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Nuri Jeong
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA 30332, USA; Neuroscience Graduate Program, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, GA, 30322, USA
| | - Lu Zhang
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Solange Amigues
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Annabelle C Singer
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA 30332, USA.
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Ryan KC, Ashkavand Z, Norman KR. The Role of Mitochondrial Calcium Homeostasis in Alzheimer's and Related Diseases. Int J Mol Sci 2020; 21:ijms21239153. [PMID: 33271784 PMCID: PMC7730848 DOI: 10.3390/ijms21239153] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/23/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023] Open
Abstract
Calcium signaling is essential for neuronal function, and its dysregulation has been implicated across neurodegenerative diseases, including Alzheimer’s disease (AD). A close reciprocal relationship exists between calcium signaling and mitochondrial function. Growing evidence in a variety of AD models indicates that calcium dyshomeostasis drastically alters mitochondrial activity which, in turn, drives neurodegeneration. This review discusses the potential pathogenic mechanisms by which calcium impairs mitochondrial function in AD, focusing on the impact of calcium in endoplasmic reticulum (ER)–mitochondrial communication, mitochondrial transport, oxidative stress, and protein homeostasis. This review also summarizes recent data that highlight the need for exploring the mechanisms underlying calcium-mediated mitochondrial dysfunction while suggesting potential targets for modulating mitochondrial calcium levels to treat neurodegenerative diseases such as AD.
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Neuron Loss in Alzheimer's Disease: Translation in Transgenic Mouse Models. Int J Mol Sci 2020; 21:ijms21218144. [PMID: 33143374 PMCID: PMC7663280 DOI: 10.3390/ijms21218144] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 10/28/2020] [Accepted: 10/28/2020] [Indexed: 02/07/2023] Open
Abstract
Transgenic mouse models represent an essential tool for the exploration of Alzheimer’s disease (AD) pathological mechanisms and the development of novel treatments, which at present provide only symptomatic and transient effects. While a variety of mouse models successfully reflects the main neuropathological hallmarks of AD, such as extracellular amyloid-β (Aβ) deposits, intracellular accumulation of Tau protein, the development of micro- and astrogliosis, as well as behavioral deficits, substantial neuron loss, as a key feature of the disease, seems to be more difficult to achieve. In this review, we summarize information on classic and more recent transgenic mouse models for AD, focusing in particular on loss of pyramidal, inter-, and cholinergic neurons. Although the cause of neuron loss in AD is still a matter of scientific debate, it seems to be linked to intraneuronal Aβ accumulation in several transgenic mouse models, especially in pyramidal neurons.
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Crapser JD, Spangenberg EE, Barahona RA, Arreola MA, Hohsfield LA, Green KN. Microglia facilitate loss of perineuronal nets in the Alzheimer's disease brain. EBioMedicine 2020; 58:102919. [PMID: 32745992 PMCID: PMC7399129 DOI: 10.1016/j.ebiom.2020.102919] [Citation(s) in RCA: 116] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Microglia, the brain's principal immune cell, are increasingly implicated in Alzheimer's disease (AD), but the molecular interfaces through which these cells contribute to amyloid beta (Aβ)-related neurodegeneration are unclear. We recently identified microglial contributions to the homeostatic and disease-associated modulation of perineuronal nets (PNNs), extracellular matrix structures that enwrap and stabilize neuronal synapses, but whether PNNs are altered in AD remains controversial. METHODS Extensive histological analysis was performed on male and female 5xFAD mice at 4, 8, 12, and 18 months of age to assess plaque burden, microgliosis, and PNNs. Findings were validated in postmortem AD tissue. The role of neuroinflammation in PNN loss was investigated via LPS treatment, and the ability to prevent or rescue disease-related reductions in PNNs was assessed by treating 5xFAD and 3xTg-AD model mice with colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX5622 to deplete microglia. FINDINGS Utilizing the 5xFAD mouse model and human cortical tissue, we report that PNNs are extensively lost in AD in proportion to plaque burden. Activated microglia closely associate with and engulf damaged nets in the 5xFAD brain, and inclusions of PNN material are evident in mouse and human microglia, while aggrecan, a critical PNN component, deposits within human dense-core plaques. Disease-associated reductions in parvalbumin (PV)+ interneurons, frequently coated by PNNs, are preceded by PNN coverage and integrity impairments, and similar phenotypes are elicited in wild-type mice following microglial activation with LPS. Chronic pharmacological depletion of microglia prevents 5xFAD PNN loss, with similar results observed following depletion in aged 3xTg-AD mice, and this occurs despite plaque persistence. INTERPRETATION We conclude that phenotypically altered microglia facilitate plaque-dependent PNN loss in the AD brain. FUNDING The NIH (NIA, NINDS) and the Alzheimer's Association.
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Affiliation(s)
- Joshua D Crapser
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | | | - Rocio A Barahona
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Miguel A Arreola
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Lindsay A Hohsfield
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Kim N Green
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA.
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Hoshi M. Multi-angle development of therapeutic methods for Alzheimer's disease. Br J Pharmacol 2020; 178:770-783. [PMID: 32592177 DOI: 10.1111/bph.15174] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 06/07/2020] [Accepted: 06/09/2020] [Indexed: 01/01/2023] Open
Abstract
Recent clinical trial results support the idea that treatment based on the so-called amyloid hypothesis is a promising approach in Alzheimer's disease (AD), but actually, developing effective treatments for AD remains highly challenging. The discovery that neuron-specific sodium pump activity is impaired in AD and other neurodegenerative diseases such as Parkinson's disease has suggested a role for the sodium pump in the pathogenesis of these diseases. This opens up new possibilities for intervention, such as inhibiting the aberrant interaction of the sodium pump with the disease-specific ligand(s) or activating the sodium pump itself or its downstream signalling. In this review article, I would like to discuss possible anti-amyloid therapies, focusing especially on our own research. LINKED ARTICLES: This article is part of a themed issue on Neurochemistry in Japan. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.4/issuetoc.
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Affiliation(s)
- Minako Hoshi
- Department for Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe, Japan
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