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Cheung S, Zhong Y, Wu L, Jia X, He MQ, Ai Y, Jiao Q, Liang Q. Mechanism interpretation of Guhan Yangshengjing for protection against Alzheimer's disease by network pharmacology and molecular docking. JOURNAL OF ETHNOPHARMACOLOGY 2024; 328:117976. [PMID: 38492794 DOI: 10.1016/j.jep.2024.117976] [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: 11/16/2023] [Revised: 02/20/2024] [Accepted: 02/24/2024] [Indexed: 03/18/2024]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Guhan Yangshengjing (GHYSJ) is an effective prescription for delaying progression of Alzheimer's disease (AD) based on the ancient Chinese medical classics excavated from Mawangdui Han Tomb. Comprising a combination of eleven traditional Chinese herbs, the precise protective mechanism through which GHYSJ acts on AD progression remains unclear and has significant implications for the development of new drugs to treat AD. AIM OF THE STUDY To investigate the mechanism of GHYSJ in the treatment of AD through network pharmacology and validate the results through in vitro experiments. MATERIALS AND METHODS Chemical composition-target-pathway network and protein-protein interaction network were constructed by network pharmacology to predict the potential targets of GHYSJ for the treatment of AD. The interaction relationship between active ingredients and targets was verified by molecular docking and molecular force. Furthermore, the chemical constituents of GHYSJ were analyzed by LC-MS and HPLC, the effects of GHYSJ on animal tissues were analyzed by H&E staining. An Aβ-induced SH-SY5Y cellular model was established to validate the core pathways and targets predicted by network pharmacology and molecular docking. RESULTS The results of the network pharmacology analysis revealed a total of 155 bioactive compounds capable of crossing the blood-brain barrier and interacting with 677 targets, among which 293 targets specifically associated with AD, which mainly participated in and regulated the amyloid aggregation pathway and PI3K/Akt signaling pathway, thereby treating AD. In addition, molecular docking analysis revealed a robust binding affinity between the principal bioactive constituents of GHYSJ and crucial targets implicated in AD. Our findings were further substantiated by in vitro experiments, which demonstrated that Liquiritigenin and Ginsenosides Rh4, crucial constituents of GHYSJ, as well as GHYSJ pharmaceutic serum, exhibited a significant down-regulation of BACE1 expression in Aβ-induced damaged SH-SY5Y cells. This study provides valuable data and theoretical underpinning for the potential therapeutic application of GHYSJ in the treatment of AD and secondary development of GHYSJ prescription. CONCLUSION Through network pharmacology, molecular docking, LC-MS, and cellular experiments, GHYSJ was initially confirmed to delay the progression of AD by regulating the expression of BACE1 in Amyloid aggregation pathway. Our observations provided valuable data and theoretical underpinning for the potential therapeutic application of GHYSJ in the treatment of AD.
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Affiliation(s)
- Suet Cheung
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, SATCM Key Laboratory of Traditional Chinese Medicine Chemistry, Institute of Traditional Chinese Medicine-X, Chinese Medicine Modernization Research Center, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | | | - Lei Wu
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, SATCM Key Laboratory of Traditional Chinese Medicine Chemistry, Institute of Traditional Chinese Medicine-X, Chinese Medicine Modernization Research Center, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Xiaomeng Jia
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, SATCM Key Laboratory of Traditional Chinese Medicine Chemistry, Institute of Traditional Chinese Medicine-X, Chinese Medicine Modernization Research Center, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Meng-Qi He
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, SATCM Key Laboratory of Traditional Chinese Medicine Chemistry, Institute of Traditional Chinese Medicine-X, Chinese Medicine Modernization Research Center, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yongjian Ai
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, SATCM Key Laboratory of Traditional Chinese Medicine Chemistry, Institute of Traditional Chinese Medicine-X, Chinese Medicine Modernization Research Center, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | | | - Qionglin Liang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, SATCM Key Laboratory of Traditional Chinese Medicine Chemistry, Institute of Traditional Chinese Medicine-X, Chinese Medicine Modernization Research Center, Department of Chemistry, Tsinghua University, Beijing, 100084, China.
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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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Stephens GS, Park J, Eagle A, You J, Silva-Pérez M, Fu CH, Choi S, Romain CPS, Sugimoto C, Buffington SA, Zheng Y, Costa-Mattioli M, Liu Y, Robison AJ, Chin J. Persistent ∆FosB expression limits recurrent seizure activity and provides neuroprotection in the dentate gyrus of APP mice. Prog Neurobiol 2024; 237:102612. [PMID: 38642602 DOI: 10.1016/j.pneurobio.2024.102612] [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: 04/03/2023] [Revised: 03/14/2024] [Accepted: 04/12/2024] [Indexed: 04/22/2024]
Abstract
Recurrent seizures lead to accumulation of the activity-dependent transcription factor ∆FosB in hippocampal dentate granule cells in both mouse models of epilepsy and mouse models of Alzheimer's disease (AD), which is also associated with increased incidence of seizures. In patients with AD and related mouse models, the degree of ∆FosB accumulation corresponds with increasing severity of cognitive deficits. We previously found that ∆FosB impairs spatial memory in mice by epigenetically regulating expression of target genes such as calbindin that are involved in synaptic plasticity. However, the suppression of calbindin in conditions of neuronal hyperexcitability has been demonstrated to provide neuroprotection to dentate granule cells, indicating that ∆FosB may act over long timescales to coordinate neuroprotective pathways. To test this hypothesis, we used viral-mediated expression of ∆JunD to interfere with ∆FosB signaling over the course of several months in transgenic mice expressing mutant human amyloid precursor protein (APP), which exhibit spontaneous seizures and develop AD-related neuropathology and cognitive deficits. Our results demonstrate that persistent ∆FosB activity acts through discrete modes of hippocampal target gene regulation to modulate neuronal excitability, limit recurrent seizure activity, and provide neuroprotection to hippocampal dentate granule cells in APP mice.
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Affiliation(s)
| | - Jin Park
- Department of Neuroscience, Baylor College of Medicine, USA
| | - Andrew Eagle
- Department of Physiology, Michigan State University, USA
| | - Jason You
- Department of Neuroscience, Baylor College of Medicine, USA
| | | | - Chia-Hsuan Fu
- Department of Neuroscience, Baylor College of Medicine, USA
| | - Sumin Choi
- Department of Neuroscience, Baylor College of Medicine, USA
| | | | - Chiho Sugimoto
- Department of Physiology, Michigan State University, USA
| | - Shelly A Buffington
- Center for Precision Environmental Health, Department of Neuroscience, Baylor College of Medicine, USA
| | - Yi Zheng
- Department of Neuroscience, Baylor College of Medicine, USA
| | | | - Yin Liu
- Department of Neurobiology and Anatomy, McGovern Medical School at UT Health, USA
| | - A J Robison
- Department of Physiology, Michigan State University, USA
| | - Jeannie Chin
- Department of Neuroscience, Baylor College of Medicine, USA.
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Slutsky I. Linking activity dyshomeostasis and sleep disturbances in Alzheimer disease. Nat Rev Neurosci 2024; 25:272-284. [PMID: 38374463 DOI: 10.1038/s41583-024-00797-y] [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: 01/30/2024] [Indexed: 02/21/2024]
Abstract
The presymptomatic phase of Alzheimer disease (AD) starts with the deposition of amyloid-β in the cortex and begins a decade or more before the emergence of cognitive decline. The trajectory towards dementia and neurodegeneration is shaped by the pathological load and the resilience of neural circuits to the effects of this pathology. In this Perspective, I focus on recent advances that have uncovered the vulnerability of neural circuits at early stages of AD to hyperexcitability, particularly when the brain is in a low-arousal states (such as sleep and anaesthesia). Notably, this hyperexcitability manifests before overt symptoms such as sleep and memory deficits. Using the principles of control theory, I analyse the bidirectional relationship between homeostasis of neuronal activity and sleep and propose that impaired activity homeostasis during sleep leads to hyperexcitability and subsequent sleep disturbances, whereas sleep disturbances mitigate hyperexcitability via negative feedback. Understanding the interplay among activity homeostasis, neuronal excitability and sleep is crucial for elucidating the mechanisms of vulnerability to and resilience against AD pathology and for identifying new therapeutic avenues.
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Affiliation(s)
- Inna Slutsky
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
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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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Alcantara-Gonzalez D, Kennedy M, Criscuolo C, Botterill J, Scharfman HE. Increased excitability of dentate gyrus mossy cells occurs early in life in the Tg2576 model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.09.579729. [PMID: 38645244 PMCID: PMC11027210 DOI: 10.1101/2024.02.09.579729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
INTRODUCTION Hyperexcitability in Alzheimer's disease (AD) emerge early and contribute to disease progression. The dentate gyrus (DG) is implicated in hyperexcitability in AD. We hypothesized that mossy cells (MCs), regulators of DG excitability, contribute to early hyperexcitability in AD. Indeed, MCs generate hyperexcitability in epilepsy. METHODS Using the Tg2576 model and WT mice (∼1month-old), we compared MCs electrophysiologically, assessed c-Fos activity marker, Aβ expression and mice performance in a hippocampal-dependent memory task. RESULTS Tg2576 MCs exhibit increased spontaneous excitatory events and decreased inhibitory currents, increasing the charge transfer excitation/inhibition ratio. Tg2576 MC intrinsic excitability was enhanced, and showed higher c-Fos, intracellular Aβ expression, and axon sprouting. Granule cells only showed changes in synaptic properties, without intrinsic changes. The effects occurred before a memory task is affected. DISCUSSION Early electrophysiological and morphological alterations in Tg2576 MCs are consistent with enhanced excitability, suggesting an early role in DG hyperexcitability and AD pathophysiology. HIGHLIGHTS ∘ MCs from 1 month-old Tg2576 mice had increased spontaneous excitatory synaptic input. ∘ Tg2576 MCs had reduced spontaneous inhibitory synaptic input. ∘ Several intrinsic properties were abnormal in Tg2576 MCs. ∘ Tg2576 GCs had enhanced synaptic excitation but no changes in intrinsic properties. ∘ Tg2576 MCs exhibited high c-Fos expression, soluble Aβ and axonal sprouting.
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Morgan DG, Lamb BT. Transgenic amyloid precursor protein mouse models of amyloidosis. Incomplete models for Alzheimer's disease but effective predictors of anti-amyloid therapies. Alzheimers Dement 2024; 20:1459-1464. [PMID: 38085800 PMCID: PMC10916971 DOI: 10.1002/alz.13566] [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: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 02/22/2024]
Abstract
INTRODUCTION Amyloid precursor protein (APP) transgenic mice are models of Alzheimer's disease (AD) amyloidosis, not all of AD. Diffuse, compacted, and vascular deposits in APP mice mimic those found in AD cases. METHODS Most interventional studies in APP mice start treatment early in the process of amyloid deposition, consistent with a prevention treatment regimen. Most clinical trials treat patients with established amyloid deposits in a therapeutic treatment regimen. RESULTS The first treatment to reduce amyloid and cognitive impairment in mice was immunotherapy. The APP mouse models not only predicted efficacy, but presaged the vascular leakage called ARIA. The recent immunotherapy clinical trials that removed amyloid and slowed cognitive decline confirms the utility of these early APP models when used in therapeutic designs. DISCUSSION New mouse models of AD pathologies will add to the research armamentarium, but the early models have accurately predicted responses to amyloid therapies in humans.
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Affiliation(s)
- David G. Morgan
- Department of Translational Neuroscience, and Alzheimer's AllianceCollege of Human MedicineMichigan State UniversityGrand RapidsMichiganUSA
| | - Bruce T. Lamb
- Department of Medical and Molecular GeneticsStark Neurosciences Research InstituteIndianapolisIndianaUSA
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Goettemoeller AM, Banks E, McCann KE, Kumar P, South K, Olah VJ, Ramelow CC, Duong DM, Seyfried NT, Rangaraju S, Weinshenker D, Rowan MJM. Entorhinal cortex vulnerability to human APP expression promotes hyperexcitability and tau pathology. RESEARCH SQUARE 2023:rs.3.rs-3370607. [PMID: 37987015 PMCID: PMC10659529 DOI: 10.21203/rs.3.rs-3370607/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Preventative treatment for Alzheimer's Disease is of dire importance, and yet, cellular mechanisms underlying early regional vulnerability in Alzheimer's Disease remain unknown. In human patients with Alzheimer's Disease, one of the earliest observed pathophysiological correlates to cognitive decline is hyperexcitability1. In mouse models, early hyperexcitability has been shown in the entorhinal cortex, the first cortical region impacted by Alzheimer's Disease2-4. The origin of hyperexcitability in early-stage disease and why it preferentially emerges in specific regions is unclear. Using cortical-region and cell-type- specific proteomics and patch-clamp electrophysiology, we uncovered differential susceptibility to human-specific amyloid precursor protein (hAPP) in a model of sporadic Alzheimer's. Unexpectedly, our findings reveal that early entorhinal hyperexcitability may result from intrinsic vulnerability of parvalbumin interneurons, rather than the suspected layer II excitatory neurons. This vulnerability of entorhinal PV interneurons is specific to hAPP, as it could not be recapitulated with increased murine APP expression. Furthermore, the Somatosensory Cortex showed no such vulnerability to adult-onset hAPP expression, likely resulting from PV-interneuron variability between the two regions based on physiological and proteomic evaluations. Interestingly, entorhinal hAPP-induced hyperexcitability was quelled by co-expression of human Tau at the expense of increased pathological tau species. This study suggests early disease interventions targeting non-excitatory cell types may protect regions with early vulnerability to pathological symptoms of Alzheimer's Disease and downstream cognitive decline.
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Affiliation(s)
- Annie M Goettemoeller
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322
- GDBBS Graduate Program, Laney Graduate School, Emory University
| | - Emmie Banks
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322
- GDBBS Graduate Program, Laney Graduate School, Emory University
| | | | - Prateek Kumar
- Department of Neurology, Emory University School of Medicine
| | - Kelly South
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322
- GDBBS Graduate Program, Laney Graduate School, Emory University
| | - Viktor J Olah
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322
| | - Christina C Ramelow
- Department of Neurology, Emory University School of Medicine
- GDBBS Graduate Program, Laney Graduate School, Emory University
| | - Duc M Duong
- Department of Neurology, Emory University School of Medicine
- Department of Biochemistry, Emory University
| | - Nicholas T Seyfried
- Department of Neurology, Emory University School of Medicine
- Department of Biochemistry, Emory University
- Center for Neurodegenerative Disease, Emory University School of Medicine
| | - Srikant Rangaraju
- Department of Neurology, Emory University School of Medicine
- GDBBS Graduate Program, Laney Graduate School, Emory University
| | | | - Matthew JM Rowan
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322
- Center for Neurodegenerative Disease, Emory University School of Medicine
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Das M, Mao W, Voskobiynyk Y, Necula D, Lew I, Petersen C, Zahn A, Yu GQ, Yu X, Smith N, Sayed FA, Gan L, Paz JT, Mucke L. Alzheimer risk-increasing TREM2 variant causes aberrant cortical synapse density and promotes network hyperexcitability in mouse models. Neurobiol Dis 2023; 186:106263. [PMID: 37591465 PMCID: PMC10681293 DOI: 10.1016/j.nbd.2023.106263] [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: 05/12/2023] [Revised: 07/12/2023] [Accepted: 08/14/2023] [Indexed: 08/19/2023] Open
Abstract
The R47H variant of triggering receptor expressed on myeloid cells 2 (TREM2) increases the risk of Alzheimer's disease (AD). To investigate potential mechanisms, we analyzed knockin mice expressing human TREM2-R47H from one mutant mouse Trem2 allele. TREM2-R47H mice showed increased seizure activity in response to an acute excitotoxin challenge, compared to wildtype controls or knockin mice expressing the common variant of human TREM2. TREM2-R47H also increased spontaneous thalamocortical epileptiform activity in App knockin mice expressing amyloid precursor proteins bearing autosomal dominant AD mutations and a humanized amyloid-β sequence. In mice with or without such App modifications, TREM2-R47H increased the density of putative synapses in cortical regions without amyloid plaques. TREM2-R47H did not affect synaptic density in hippocampal regions with or without plaques. We conclude that TREM2-R47H increases AD-related network hyperexcitability and that it may do so, at least in part, by causing an imbalance in synaptic densities across brain regions.
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Affiliation(s)
- Melanie Das
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Wenjie Mao
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Yuliya Voskobiynyk
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Deanna Necula
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Neuroscience Graduate Program, University of California, San Francisco, CA 94158, USA
| | - Irene Lew
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Cathrine Petersen
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Neuroscience Graduate Program, University of California, San Francisco, CA 94158, USA
| | - Allie Zahn
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Gui-Qiu Yu
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Xinxing Yu
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Nicholas Smith
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Faten A Sayed
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Li Gan
- Helen and Robert Appel Alzheimer's Disease Research Institute, Weill Cornell Medicine, New York City, NY 10065, USA
| | - Jeanne T Paz
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Neuroscience Graduate Program, University of California, San Francisco, CA 94158, USA; Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, CA 94158, USA
| | - Lennart Mucke
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Neuroscience Graduate Program, University of California, San Francisco, CA 94158, USA; Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, CA 94158, USA.
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Wright AL, Konen LM, Mockett BG, Morris GP, Singh A, Burbano LE, Milham L, Hoang M, Zinn R, Chesworth R, Tan RP, Royle GA, Clark I, Petrou S, Abraham WC, Vissel B. The Q/R editing site of AMPA receptor GluA2 subunit acts as an epigenetic switch regulating dendritic spines, neurodegeneration and cognitive deficits in Alzheimer's disease. Mol Neurodegener 2023; 18:65. [PMID: 37759260 PMCID: PMC10537207 DOI: 10.1186/s13024-023-00632-5] [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: 01/11/2023] [Accepted: 06/03/2023] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND RNA editing at the Q/R site of GluA2 occurs with ~99% efficiency in the healthy brain, so that the majority of AMPARs contain GluA2(R) instead of the exonically encoded GluA2(Q). Reduced Q/R site editing infcreases AMPA receptor calcium permeability and leads to dendritic spine loss, neurodegeneration, seizures and learning impairments. Furthermore, GluA2 Q/R site editing is impaired in Alzheimer's disease (AD), raising the possibility that unedited GluA2(Q)-containing AMPARs contribute to synapse loss and neurodegeneration in AD. If true, then inhibiting expression of unedited GluA2(Q), while maintaining expression of GluA2(R), may be a novel strategy of preventing synapse loss and neurodegeneration in AD. METHODS We engineered mice with the 'edited' arginine codon (CGG) in place of the unedited glutamine codon (CAG) at position 607 of the Gria2 gene. We crossbred this line with the J20 mouse model of AD and conducted anatomical, electrophysiological and behavioural assays to determine the impact of eliminating unedited GluA2(Q) expression on AD-related phenotypes. RESULTS Eliminating unedited GluA2(Q) expression in AD mice prevented dendritic spine loss and hippocampal CA1 neurodegeneration as well as improved working and reference memory in the radial arm maze. These phenotypes were improved independently of Aβ pathology and ongoing seizure susceptibility. Surprisingly, our data also revealed increased spine density in non-AD mice with exonically encoded GluA2(R) as compared to their wild-type littermates, suggesting an unexpected and previously unknown role for unedited GluA2(Q) in regulating dendritic spines. CONCLUSION The Q/R editing site of the AMPA receptor subunit GluA2 may act as an epigenetic switch that regulates dendritic spines, neurodegeneration and memory deficits in AD.
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Affiliation(s)
- Amanda L Wright
- St Vincent's Clinical School, St Vincent's Hospital Sydney, Faculty of Medicine, University of New South Wales, Darlinghurst, NSW, 2010, Australia
- School of Rural Medicine, Charles Sturt University, Orange, NSW, 2800, Australia
| | - Lyndsey M Konen
- Centre for Neuroscience and Regenerative Medicine, St Vincent's Centre for Applied Medical Research, St Vincent's Hospital Sydney, Darlinghurst, NSW, 2010, Australia
| | - Bruce G Mockett
- Department of Psychology, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Box 56, Dunedin, 9054, New Zealand
| | - Gary P Morris
- Centre for Neuroscience and Regenerative Medicine, St Vincent's Centre for Applied Medical Research, St Vincent's Hospital Sydney, Darlinghurst, NSW, 2010, Australia
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, TAS, 7005, Australia
| | - Anurag Singh
- Department of Psychology, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Box 56, Dunedin, 9054, New Zealand
| | - Lisseth Estefania Burbano
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3010, Australia
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Luke Milham
- St Vincent's Clinical School, St Vincent's Hospital Sydney, Faculty of Medicine, University of New South Wales, Darlinghurst, NSW, 2010, Australia
- Centre for Neuroscience and Regenerative Medicine, St Vincent's Centre for Applied Medical Research, St Vincent's Hospital Sydney, Darlinghurst, NSW, 2010, Australia
| | - Monica Hoang
- School of Pharmacy, University of Waterloo, Kitchener, ON, N2G 1C5, Canada
| | - Raphael Zinn
- Centre for Neuroscience and Regenerative Medicine, St Vincent's Centre for Applied Medical Research, St Vincent's Hospital Sydney, Darlinghurst, NSW, 2010, Australia
| | - Rose Chesworth
- School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | - Richard P Tan
- Chronic Diseases, School of Medical Sciences, Faculty of Health and Medicine, University of Sydney, Sydney, NSW, 2050, Australia
- Charles Perkins Centre, University of Sydney, Sydney, NSW, 2006, Australia
| | - Gordon A Royle
- Middlemore Hospital, Counties Manukau DHB, Otahuhu, Auckland, 1062, New Zealand
- Faculty of Medical and Health Sciences, University of Auckland, Grafton, Auckland, 1023, New Zealand
| | - Ian Clark
- Research School of Biology, Australian National University, Canberra, ACT, 0200, Australia
| | - Steven Petrou
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3010, Australia
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Wickliffe C Abraham
- Department of Psychology, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Box 56, Dunedin, 9054, New Zealand
| | - Bryce Vissel
- St Vincent's Clinical School, St Vincent's Hospital Sydney, Faculty of Medicine, University of New South Wales, Darlinghurst, NSW, 2010, Australia.
- Centre for Neuroscience and Regenerative Medicine, St Vincent's Centre for Applied Medical Research, St Vincent's Hospital Sydney, Darlinghurst, NSW, 2010, Australia.
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11
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Vande Vyver M, Daeninck L, De Smet G, Aourz N, Sahu S, Engelborghs S, Pauwels K, De Bundel D, Smolders I. The intracerebral injection of Aβ 1-42 oligomers does not invariably alter seizure susceptibility in mice. Front Aging Neurosci 2023; 15:1239140. [PMID: 37744393 PMCID: PMC10512828 DOI: 10.3389/fnagi.2023.1239140] [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: 06/12/2023] [Accepted: 08/22/2023] [Indexed: 09/26/2023] Open
Abstract
Objectives Epileptiform activity and seizures are present in patients with Alzheimer's disease (AD) and genetic animal models of AD. Amyloid beta 1-42 (Aβ1-42) oligomers are thought to be crucial in AD and can cause neuronal hyperexcitability in vitro. However, it is unclear whether these Aβ1-42 oligomers cause the increased seizure susceptibility in vivo in people with AD and in AD animal models, nor via which mechanisms it would do so. We investigated this question by injecting Aβ1-42 oligomers intracerebrally in mice and assessed its impact on seizure susceptibility. Materials and methods We performed a single intracerebral injection of synthetic Aβ1-42 oligomers or scrambled Aβ1-42 in NMRI mice in three different cohorts and subjected them to an i.v. infusion of a chemoconvulsant. We evoked the seizures 1.5 h, 1 week, or 3 weeks after the intracerebral injection of Aβ1-42 oligomers, covering also the timepoints and injection locations that were used by others in similar experimental set-ups. Results With a thioflavine T assay and transmission electron microscopy we confirmed that Aβ1-42 monomers spontaneously aggregated to oligomers. We did not find an effect of Aβ1-42 oligomers on susceptibility to seizures - evoked 1.5 h, 1 week or 3 weeks - after their intracerebral injection. Significance The lack of effect of Aβ1-42 oligomers on seizure susceptibility in our experiments contrasts with recent findings in similar experimental set-ups. Contradicting conclusions are frequent in experiments with Aβ1-42 and they are often attributed to subtle differences in the various aggregation forms of the Aβ1-42 used in different experiments. We confirmed the presence of Aβ1-42 oligomers with state-of-the-art methods but cannot ascertain that the protein aggregates we used are identical to those used by others. Whether our findings or those previously published best represent the role of Aβ1-42 oligomers on seizures in AD remains unclear.
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Affiliation(s)
- Maxime Vande Vyver
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
- Department of Neurology and Bru-BRAIN, Universitair Ziekenhuis Brussel, Brussels, Belgium
- NEUR Research Group, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
- Department of Biomedical Sciences, Reference Center for Biological Markers of Dementia (BIODEM), University of Antwerp, Antwerp, Belgium
| | - Louise Daeninck
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
| | - Gino De Smet
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
| | - Najat Aourz
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
| | - Surajit Sahu
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
| | - Sebastiaan Engelborghs
- Department of Neurology and Bru-BRAIN, Universitair Ziekenhuis Brussel, Brussels, Belgium
- NEUR Research Group, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
- Department of Biomedical Sciences, Reference Center for Biological Markers of Dementia (BIODEM), University of Antwerp, Antwerp, Belgium
| | - Kris Pauwels
- RESEARCH Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Dimitri De Bundel
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
| | - Ilse Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences (C4N), Vrije Universiteit Brussel, Brussels, Belgium
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12
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Israel LL, Sun T, Braubach O, Cox A, Shatalova ES, Rashid HM, Galstyan A, Grodzinski Z, Song XY, Chepurna O, Ljubimov VA, Chiechi A, Sharma S, Phebus C, Wang Y, Ljubimova JY, Black KL, Holler E. β-Amyloid targeting nanodrug for neuron-specific delivery of nucleic acids in Alzheimer's disease mouse models. J Control Release 2023; 361:636-658. [PMID: 37544515 DOI: 10.1016/j.jconrel.2023.08.001] [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: 02/17/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/08/2023]
Abstract
Delivery of therapeutic substances into the brain poses a significant challenge in the treatment of neurological disorders. This is primarily due to the blood-brain barrier (BBB), which restricts access, alongside the limited stability and distribution of these agents within the brain tissue. Here we demonstrate an efficient delivery of microRNA (miRNA) and antisense RNA preferentially to neurons compared to astroglia in the brain of healthy and Alzheimer's disease mice, via disulfide-linked conjugation with poly(ß-L-malic acid-trileucine)-copolymer a biodegradable, amphiphilic, and multivalent platform. By conjugating a D-configured (D3)-peptide (vector) for specific targeting, highly efficient delivery across the BBB is achieved through the Low-Density Lipoprotein Receptor-Related Protein-1 (LRP-1) transcytosis pathway, amyloid beta (Aβ) peptides. Nanodrug distribution was determined by fluorescent labeling and analyzed by microscopy in neurons, astroglia, and in extracellular amyloid plaques typical for Alzheimer's disease. Whereas D-configured BBB-vectors can efficiently target neurons, L-configured (e.g., AP2-peptide) guided vector can only cross BBB but not seem to bind neurons. An analysis of post-injection fluorescence distribution, and RNA-seq followed by real-time PCR validation, confirmed a successful in vivo delivery of morpholino-miRNA-186 nanoconjugates into mouse brain. The size and fluorescence intensity of the intracellular nanodrug particulates were analyzed and verified by a competition with non-fluorescent conjugates. Differentially expressed genes (DEGs) from RNA-seq were identified in the nanodrug injected mice, and the changes of selected DEGs related to Alzheimer's disease were further validated by western blot and real-time PCR. Collectively, these results demonstrated that D3-peptide-conjugated nanopolymer drug is able to achieve neuron-selective delivery of miRNA and can serve as an efficient brain delivery vehicle in Alzheimer's disease (AD) mouse models.
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Affiliation(s)
- Liron L Israel
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Tao Sun
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Oliver Braubach
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Alysia Cox
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | | | | | - Anna Galstyan
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Zachary Grodzinski
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Xue Ying Song
- Cedars-Sinai Cancer Applied Genomics Shared Resource, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Oksana Chepurna
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Vladimir A Ljubimov
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Antonella Chiechi
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Sachin Sharma
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Connor Phebus
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Yizhou Wang
- Cedars-Sinai Cancer Applied Genomics Shared Resource, Cedars-Sinai Medical Center, Los Angeles 90048, USA
| | - Julia Y Ljubimova
- Terasaki Institute of Biomedical Innovation, Los Angeles, 90024, USA..
| | - Keith L Black
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles 90048, USA.
| | - Eggehard Holler
- Terasaki Institute of Biomedical Innovation, Los Angeles, 90024, USA..
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13
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Long H, Zhu W, Wei L, Zhao J. Iron homeostasis imbalance and ferroptosis in brain diseases. MedComm (Beijing) 2023; 4:e298. [PMID: 37377861 PMCID: PMC10292684 DOI: 10.1002/mco2.298] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 06/29/2023] Open
Abstract
Brain iron homeostasis is maintained through the normal function of blood-brain barrier and iron regulation at the systemic and cellular levels, which is fundamental to normal brain function. Excess iron can catalyze the generation of free radicals through Fenton reactions due to its dual redox state, thus causing oxidative stress. Numerous evidence has indicated brain diseases, especially stroke and neurodegenerative diseases, are closely related to the mechanism of iron homeostasis imbalance in the brain. For one thing, brain diseases promote brain iron accumulation. For another, iron accumulation amplifies damage to the nervous system and exacerbates patients' outcomes. In addition, iron accumulation triggers ferroptosis, a newly discovered iron-dependent type of programmed cell death, which is closely related to neurodegeneration and has received wide attention in recent years. In this context, we outline the mechanism of a normal brain iron metabolism and focus on the current mechanism of the iron homeostasis imbalance in stroke, Alzheimer's disease, and Parkinson's disease. Meanwhile, we also discuss the mechanism of ferroptosis and simultaneously enumerate the newly discovered drugs for iron chelators and ferroptosis inhibitors.
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Affiliation(s)
- Haining Long
- Department of Diagnostic and Interventional RadiologyShanghai Sixth People’s Hospital Afliated to Shanghai Jiao Tong University School
of MedicineShanghaiChina
| | - Wangshu Zhu
- Department of Diagnostic and Interventional RadiologyShanghai Sixth People’s Hospital Afliated to Shanghai Jiao Tong University School
of MedicineShanghaiChina
| | - Liming Wei
- Department of Diagnostic and Interventional RadiologyShanghai Sixth People’s Hospital Afliated to Shanghai Jiao Tong University School
of MedicineShanghaiChina
| | - Jungong Zhao
- Department of Diagnostic and Interventional RadiologyShanghai Sixth People’s Hospital Afliated to Shanghai Jiao Tong University School
of MedicineShanghaiChina
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14
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Cheng GWY, Ma IWT, Huang J, Yeung SHS, Ho P, Chen Z, Mak HKF, Herrup K, Chan KWY, Tse KH. Cuprizone drives divergent neuropathological changes in different mouse models of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.24.547147. [PMID: 37546935 PMCID: PMC10402084 DOI: 10.1101/2023.07.24.547147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Myelin degradation is a normal feature of brain aging that accelerates in Alzheimer's disease (AD). To date, however, the underlying biological basis of this correlation remains elusive. The amyloid cascade hypothesis predicts that demyelination is caused by increased levels of the β-amyloid (Aβ) peptide. Here we report on work supporting the alternative hypothesis that early demyelination is upstream of amyloid. We challenged two different mouse models of AD (R1.40 and APP/PS1) using cuprizone-induced demyelination and tracked the responses with both neuroimaging and neuropathology. In oppose to amyloid cascade hypothesis, R1.40 mice, carrying only a single human mutant APP (Swedish; APP SWE ) transgene, showed a more abnormal changes of magnetization transfer ratio and diffusivity than in APP/PS1 mice, which carry both APP SWE and a second PSEN1 transgene (delta exon 9; PSEN1 dE9 ). Although cuprizone targets oligodendrocytes (OL), magnetic resonance spectroscopy and targeted RNA-seq data in R1.40 mice suggested a possible metabolic alternation in axons. In support of alternative hypotheses, cuprizone induced significant intraneuronal amyloid deposition in young APP/PS1, but not in R1.40 mice, and it suggested the presence of PSEN deficiencies, may accelerate Aβ deposition upon demyelination. In APP/PS1, mature OL is highly vulnerable to cuprizone with significant DNA double strand breaks (53BP1 + ) formation. Despite these major changes in myelin, OLs, and Aβ immunoreactivity, no cognitive impairment or hippocampal pathology was detected in APP/PS1 mice after cuprizone treatment. Together, our data supports the hypothesis that myelin loss can be the cause, but not the consequence, of AD pathology. SIGNIFICANCE STATEMENT The causal relationship between early myelin loss and the progression of Alzheimer's disease remains unclear. Using two different AD mouse models, R1.40 and APP/PS1, our study supports the hypothesis that myelin abnormalities are upstream of amyloid production and deposition. We find that acute demyelination initiates intraneuronal amyloid deposition in the frontal cortex. Further, the loss of oligodendrocytes, coupled with the accelerated intraneuronal amyloid deposition, interferes with myelin tract diffusivity at a stage before any hippocampus pathology or cognitive impairments occur. We propose that myelin loss could be the cause, not the consequence, of amyloid pathology during the early stages of Alzheimer's disease.
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15
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Falcicchia C, Tozzi F, Gabrielli M, Amoretti S, Masini G, Nardi G, Guglielmo S, Ratto GM, Arancio O, Verderio C, Origlia N. Microglial extracellular vesicles induce Alzheimer's disease-related cortico-hippocampal network dysfunction. Brain Commun 2023; 5:fcad170. [PMID: 37288314 PMCID: PMC10243901 DOI: 10.1093/braincomms/fcad170] [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: 01/05/2023] [Revised: 04/06/2023] [Accepted: 05/30/2023] [Indexed: 06/09/2023] Open
Abstract
β-Amyloid is one of the main pathological hallmarks of Alzheimer's disease and plays a major role in synaptic dysfunction. It has been demonstrated that β-amyloid can elicit aberrant excitatory activity in cortical-hippocampal networks, which is associated with behavioural abnormalities. However, the mechanism of the spreading of β-amyloid action within a specific circuitry has not been elucidated yet. We have previously demonstrated that the motion of microglia-derived large extracellular vesicles carrying β-amyloid, at the neuronal surface, is crucial for the initiation and propagation of synaptic dysfunction along the entorhinal-hippocampal circuit. Here, using chronic EEG recordings, we show that a single injection of extracellular vesicles carrying β-amyloid into the mouse entorhinal cortex could trigger alterations in the cortical and hippocampal activity that are reminiscent of those found in Alzheimer's disease mouse models and human patients. The development of EEG abnormalities was associated with progressive memory impairment as assessed by an associative (object-place context recognition) and non-associative (object recognition) task. Importantly, when the motility of extracellular vesicles, carrying β-amyloid, was inhibited, the effect on network stability and memory function was significantly reduced. Our model proposes a new biological mechanism based on the extracellular vesicles-mediated progression of β-amyloid pathology and offers the opportunity to test pharmacological treatments targeting the early stages of Alzheimer's disease.
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Affiliation(s)
- Chiara Falcicchia
- National Research Council (CNR) Institute of Neuroscience, Pisa 56124, Italy
| | - Francesca Tozzi
- National Research Council (CNR) Institute of Neuroscience, Pisa 56124, Italy
- Bio@SNS laboratory, Scuola Normale Superiore, Pisa 56124, Italy
| | - Martina Gabrielli
- National Research Council (CNR) Institute of Neuroscience, Vedano al Lambro, Monza (MB) 20854, Italy
| | - Stefano Amoretti
- National Research Council (CNR) Institute of Neuroscience, Pisa 56124, Italy
| | - Greta Masini
- National Research Council (CNR) Institute of Neuroscience, Pisa 56124, Italy
| | - Gabriele Nardi
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, Pisa 56127, Italy
| | - Stefano Guglielmo
- National Research Council (CNR) Institute of Neuroscience, Pisa 56124, Italy
- Bio@SNS laboratory, Scuola Normale Superiore, Pisa 56124, Italy
| | - Gian Michele Ratto
- National Enterprise for nanoScience and nanoTechnology (NEST), Istituto Nanoscienze, Consiglio Nazionale delle Ricerche (CNR) and Scuola Normale Superiore Pisa, Pisa 56127, Italy
| | - Ottavio Arancio
- Department of Pathology and Cell Biology, The Taub Institute for Research on Alzheimer’s Disease and the Aging Brain and Department of Medicine, Columbia University, New York, NY 10032, USA
| | - Claudia Verderio
- National Research Council (CNR) Institute of Neuroscience, Vedano al Lambro, Monza (MB) 20854, Italy
| | - Nicola Origlia
- National Research Council (CNR) Institute of Neuroscience, Pisa 56124, Italy
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16
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Calafate S, Özturan G, Thrupp N, Vanderlinden J, Santa-Marinha L, Morais-Ribeiro R, Ruggiero A, Bozic I, Rusterholz T, Lorente-Echeverría B, Dias M, Chen WT, Fiers M, Lu A, Vlaeminck I, Creemers E, Craessaerts K, Vandenbempt J, van Boekholdt L, Poovathingal S, Davie K, Thal DR, Wierda K, Oliveira TG, Slutsky I, Adamantidis A, De Strooper B, de Wit J. Early alterations in the MCH system link aberrant neuronal activity and sleep disturbances in a mouse model of Alzheimer's disease. Nat Neurosci 2023:10.1038/s41593-023-01325-4. [PMID: 37188873 DOI: 10.1038/s41593-023-01325-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 04/10/2023] [Indexed: 05/17/2023]
Abstract
Early Alzheimer's disease (AD) is associated with hippocampal hyperactivity and decreased sleep quality. Here we show that homeostatic mechanisms transiently counteract the increased excitatory drive to CA1 neurons in AppNL-G-F mice, but that this mechanism fails in older mice. Spatial transcriptomics analysis identifies Pmch as part of the adaptive response in AppNL-G-F mice. Pmch encodes melanin-concentrating hormone (MCH), which is produced in sleep-active lateral hypothalamic neurons that project to CA1 and modulate memory. We show that MCH downregulates synaptic transmission, modulates firing rate homeostasis in hippocampal neurons and reverses the increased excitatory drive to CA1 neurons in AppNL-G-F mice. AppNL-G-F mice spend less time in rapid eye movement (REM) sleep. AppNL-G-F mice and individuals with AD show progressive changes in morphology of CA1-projecting MCH axons. Our findings identify the MCH system as vulnerable in early AD and suggest that impaired MCH-system function contributes to aberrant excitatory drive and sleep defects, which can compromise hippocampus-dependent functions.
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Affiliation(s)
- Sara Calafate
- VIB Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium.
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal.
| | - Gökhan Özturan
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Nicola Thrupp
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Jeroen Vanderlinden
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Luísa Santa-Marinha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Rafaela Morais-Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Antonella Ruggiero
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ivan Bozic
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
| | - Thomas Rusterholz
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Blanca Lorente-Echeverría
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Marcelo Dias
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Wei-Ting Chen
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Mark Fiers
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Ashley Lu
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Ine Vlaeminck
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Eline Creemers
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Katleen Craessaerts
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Joris Vandenbempt
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Luuk van Boekholdt
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
- KU Leuven, Department of Otorhinolaryngology, Leuven, Belgium
| | - Suresh Poovathingal
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Kristofer Davie
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Dietmar Rudolf Thal
- Department of Imaging and Pathology, Laboratory of Neuropathology, and Leuven Brain Institute, KU-Leuven, O&N IV, Leuven, Belgium
- Department of Pathology, UZ Leuven, Leuven, Belgium
| | - Keimpe Wierda
- VIB Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium
| | - Tiago Gil Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Inna Slutsky
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Antoine Adamantidis
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Bart De Strooper
- VIB Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium.
- UK Dementia Research Institute (UK DRI@UCL) at University College London, London, UK.
| | - Joris de Wit
- VIB Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Neurosciences, Leuven Brain Institute, Leuven, Belgium.
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17
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Li H, Guglielmetti C, Sei YJ, Zilberter M, Le Page LM, Shields L, Yang J, Nguyen K, Tiret B, Gao X, Bennett N, Lo I, Dayton TL, Kampmann M, Huang Y, Rathmell JC, Vander Heiden M, Chaumeil MM, Nakamura K. Neurons require glucose uptake and glycolysis in vivo. Cell Rep 2023; 42:112335. [PMID: 37027294 PMCID: PMC10556202 DOI: 10.1016/j.celrep.2023.112335] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/22/2023] [Accepted: 03/20/2023] [Indexed: 04/08/2023] Open
Abstract
Neurons require large amounts of energy, but whether they can perform glycolysis or require glycolysis to maintain energy remains unclear. Using metabolomics, we show that human neurons do metabolize glucose through glycolysis and can rely on glycolysis to supply tricarboxylic acid (TCA) cycle metabolites. To investigate the requirement for glycolysis, we generated mice with postnatal deletion of either the dominant neuronal glucose transporter (GLUT3cKO) or the neuronal-enriched pyruvate kinase isoform (PKM1cKO) in CA1 and other hippocampal neurons. GLUT3cKO and PKM1cKO mice show age-dependent learning and memory deficits. Hyperpolarized magnetic resonance spectroscopic (MRS) imaging shows that female PKM1cKO mice have increased pyruvate-to-lactate conversion, whereas female GLUT3cKO mice have decreased conversion, body weight, and brain volume. GLUT3KO neurons also have decreased cytosolic glucose and ATP at nerve terminals, with spatial genomics and metabolomics revealing compensatory changes in mitochondrial bioenergetics and galactose metabolism. Therefore, neurons metabolize glucose through glycolysis in vivo and require glycolysis for normal function.
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Affiliation(s)
- Huihui Li
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Caroline Guglielmetti
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA
| | - Yoshitaka J Sei
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Misha Zilberter
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Lydia M Le Page
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA
| | - Lauren Shields
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA
| | - Joyce Yang
- Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA
| | - Kevin Nguyen
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Brice Tiret
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA
| | - Xiao Gao
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA; UCSF/UCB Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA 94158, USA
| | - Neal Bennett
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Iris Lo
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Talya L Dayton
- Koch Institute for Integrative Cancer Research and the Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Martin Kampmann
- Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; UCSF/UCB Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA 94158, USA; Institute for Neurodegenerative Diseases, University of California San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Yadong Huang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Jeffrey C Rathmell
- Vanderbilt Center for Immunobiology, Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Matthew Vander Heiden
- Koch Institute for Integrative Cancer Research and the Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | - Myriam M Chaumeil
- Department of Physical Therapy and Rehabilitation Science, San Francisco, CA 94158, USA; Department of Radiology and Biomedical Imaging, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; UCSF/UCB Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA 94158, USA.
| | - Ken Nakamura
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA; Graduate Program in Biomedical Sciences, University of California San Francisco, San Francisco, CA 94143, USA; Graduate Program in Neuroscience, University of California San Francisco, San Francisco, CA 94158, USA; Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA.
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18
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Niraula S, Doderer JJ, Indulkar S, Berry KP, Hauser WL, L'Esperance OJ, Deng JZ, Keeter G, Rouse AG, Subramanian J. Excitation-inhibition imbalance disrupts visual familiarity in amyloid and non-pathology conditions. Cell Rep 2023; 42:111946. [PMID: 36640331 PMCID: PMC9939293 DOI: 10.1016/j.celrep.2022.111946] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/14/2022] [Accepted: 12/15/2022] [Indexed: 01/06/2023] Open
Abstract
Neuronal hyperactivity induces memory deficits in Alzheimer's disease. However, how hyperactivity disrupts memory is unclear. Using in vivo synaptic imaging in the mouse visual cortex, we show that structural excitatory-inhibitory synapse imbalance in the apical dendrites favors hyperactivity in early amyloidosis. Consistent with this, natural images elicit neuronal hyperactivity in these mice. Compensatory changes that maintain activity homeostasis disrupt functional connectivity and increase population sparseness such that a small fraction of neurons dominates population activity. These properties reduce the selectivity of neural response to natural images and render visual recognition memory vulnerable to interference. Deprivation of non-specific visual experiences improves the neural representation and behavioral expression of visual familiarity. In contrast, in non-pathological conditions, deprivation of non-specific visual experiences induces disinhibition, increases excitability, and disrupts visual familiarity. We show that disrupted familiarity occurs when the fraction of high-responsive neurons and the persistence of neural representation of a memory-associated stimulus are not constrained.
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Affiliation(s)
- Suraj Niraula
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Julia J Doderer
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Shreya Indulkar
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Kalen P Berry
- Division of Experimental Hematology and Cancer Biology, Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - William L Hauser
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Oliver J L'Esperance
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Jasmine Z Deng
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Griffin Keeter
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA
| | - Adam G Rouse
- Department of Neurosurgery, University of Kansas Medical Center, Kansas City, KS 66103, USA
| | - Jaichandar Subramanian
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA.
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19
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Gorina YV, Vlasova OL, Bolshakova AV, Salmina AB. Alzheimer’s Disease: a Search for the Best Experimental Models to Decode Cellular and Molecular Mechanisms of Its Development. J EVOL BIOCHEM PHYS+ 2023. [DOI: 10.1134/s0022093023010106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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20
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Brown JL, Hart DW, Boyle GE, Brown TG, LaCroix M, Baraibar AM, Pelzel R, Kim M, Sherman MA, Boes S, Sung M, Cole T, Lee MK, Araque A, Lesné SE. SNCA genetic lowering reveals differential cognitive function of alpha-synuclein dependent on sex. Acta Neuropathol Commun 2022; 10:180. [PMID: 36517890 PMCID: PMC9749314 DOI: 10.1186/s40478-022-01480-y] [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: 08/23/2022] [Accepted: 11/18/2022] [Indexed: 12/15/2022] Open
Abstract
Antisense oligonucleotide (ASO) therapy for neurological disease has been successful in clinical settings and its potential has generated hope for Alzheimer's disease (AD). We previously described that ablating SNCA encoding for α-synuclein (αSyn) in a mouse model of AD was beneficial. Here, we sought to demonstrate whether transient reduction of αSyn expression using ASOSNCA could be therapeutic in a mouse model of AD. The efficacy of the ASOSNCA was measured via immunocytochemistry, RT-qPCR and western blotting. To assess spatial learning and memory, ASOSNCA or PBS-injected APP and non-transgenic (NTG) mice, and separate groups of SNCA-null mice, were tested on the Barnes circular maze. Hippocampal slice electrophysiology and transcriptomic profiling were used to explore synaptic function and differential gene expression between groups. Reduction of SNCA transcripts alleviated cognitive deficits in male transgenic animals, but surprisingly, not in females. To determine the functional cause of this differential effect, we assessed memory function in SNCA-null mice. Learning and memory were intact in male mice but impaired in female animals, revealing that the role of αSyn on cognitive function is sex-specific. Transcriptional analyses identified a differentially expressed gene network centered around EGR1, a central modulator of learning and memory, in the hippocampi of SNCA-null mice. Thus, these novel results demonstrate that the function of αSyn on memory differs between male and female brains.
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Affiliation(s)
- Jennifer L. Brown
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN USA
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Damyan W. Hart
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Gabriel E. Boyle
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
- Present Address: Graduate Program in Molecular and Cellular Biology, University of Washington, Seattle, WA 98195 USA
| | - Taylor G. Brown
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Medical Scientist Training Program, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Michael LaCroix
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
- Present Address: Medical Scientist Training Program, University of Texas Southwestern Medical School, Dallas, TX 75390 USA
| | - Andrés M. Baraibar
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Present Address: Department of Neurosciences, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Ross Pelzel
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN USA
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Minwoo Kim
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Mathew A. Sherman
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Samuel Boes
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Michelle Sung
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
- Present Address: Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21218 USA
| | - Tracy Cole
- Ionis Pharmaceuticals Inc., Carlsbad, CA USA
- Present Address: n-Lorem Foundation, Carlsbad, CA 92010 USA
| | - Michael K. Lee
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
| | - Alfonso Araque
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN USA
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
| | - Sylvain E. Lesné
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN USA
- Department of Neuroscience, University of Minnesota, Minneapolis, MN USA
- Institute for Translational Neuroscience, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414 USA
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21
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Olah VJ, Goettemoeller AM, Rayaprolu S, Dammer EB, Seyfried NT, Rangaraju S, Dimidschstein J, Rowan MJM. Biophysical Kv3 channel alterations dampen excitability of cortical PV interneurons and contribute to network hyperexcitability in early Alzheimer's. eLife 2022; 11:75316. [PMID: 35727131 PMCID: PMC9278953 DOI: 10.7554/elife.75316] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 05/19/2022] [Indexed: 11/13/2022] Open
Abstract
In Alzheimer’s disease (AD), a multitude of genetic risk factors and early biomarkers are known. Nevertheless, the causal factors responsible for initiating cognitive decline in AD remain controversial. Toxic plaques and tangles correlate with progressive neuropathology, yet disruptions in circuit activity emerge before their deposition in AD models and patients. Parvalbumin (PV) interneurons are potential candidates for dysregulating cortical excitability as they display altered action potential (AP) firing before neighboring excitatory neurons in prodromal AD. Here, we report a novel mechanism responsible for PV hypoexcitability in young adult familial AD mice. We found that biophysical modulation of Kv3 channels, but not changes in their mRNA or protein expression, were responsible for dampened excitability in young 5xFAD mice. These K+ conductances could efficiently regulate near-threshold AP firing, resulting in gamma-frequency-specific network hyperexcitability. Thus, biophysical ion channel alterations alone may reshape cortical network activity prior to changes in their expression levels. Our findings demonstrate an opportunity to design a novel class of targeted therapies to ameliorate cortical circuit hyperexcitability in early AD.
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Affiliation(s)
- Viktor J Olah
- Department of Cell Biology, Emory University, Atlanta, United States
| | | | - Sruti Rayaprolu
- Department of Neurology, Emory University, Atlanta, United States
| | - Eric B Dammer
- Department of Biochemistry, Emory University, Atlanta, United States
| | | | | | | | - Matthew J M Rowan
- Department of Cell Biology, Emory University, Atlanta, United States
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22
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Xia D, Lianoglou S, Sandmann T, Calvert M, Suh JH, Thomsen E, Dugas J, Pizzo ME, DeVos SL, Earr TK, Lin CC, Davis S, Ha C, Leung AWS, Nguyen H, Chau R, Yulyaningsih E, Lopez I, Solanoy H, Masoud ST, Liang CC, Lin K, Astarita G, Khoury N, Zuchero JY, Thorne RG, Shen K, Miller S, Palop JJ, Garceau D, Sasner M, Whitesell JD, Harris JA, Hummel S, Gnörich J, Wind K, Kunze L, Zatcepin A, Brendel M, Willem M, Haass C, Barnett D, Zimmer TS, Orr AG, Scearce-Levie K, Lewcock JW, Di Paolo G, Sanchez PE. Novel App knock-in mouse model shows key features of amyloid pathology and reveals profound metabolic dysregulation of microglia. Mol Neurodegener 2022; 17:41. [PMID: 35690868 PMCID: PMC9188195 DOI: 10.1186/s13024-022-00547-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 05/25/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Genetic mutations underlying familial Alzheimer's disease (AD) were identified decades ago, but the field is still in search of transformative therapies for patients. While mouse models based on overexpression of mutated transgenes have yielded key insights in mechanisms of disease, those models are subject to artifacts, including random genetic integration of the transgene, ectopic expression and non-physiological protein levels. The genetic engineering of novel mouse models using knock-in approaches addresses some of those limitations. With mounting evidence of the role played by microglia in AD, high-dimensional approaches to phenotype microglia in those models are critical to refine our understanding of the immune response in the brain. METHODS We engineered a novel App knock-in mouse model (AppSAA) using homologous recombination to introduce three disease-causing coding mutations (Swedish, Arctic and Austrian) to the mouse App gene. Amyloid-β pathology, neurodegeneration, glial responses, brain metabolism and behavioral phenotypes were characterized in heterozygous and homozygous AppSAA mice at different ages in brain and/ or biofluids. Wild type littermate mice were used as experimental controls. We used in situ imaging technologies to define the whole-brain distribution of amyloid plaques and compare it to other AD mouse models and human brain pathology. To further explore the microglial response to AD relevant pathology, we isolated microglia with fibrillar Aβ content from the brain and performed transcriptomics and metabolomics analyses and in vivo brain imaging to measure energy metabolism and microglial response. Finally, we also characterized the mice in various behavioral assays. RESULTS Leveraging multi-omics approaches, we discovered profound alteration of diverse lipids and metabolites as well as an exacerbated disease-associated transcriptomic response in microglia with high intracellular Aβ content. The AppSAA knock-in mouse model recapitulates key pathological features of AD such as a progressive accumulation of parenchymal amyloid plaques and vascular amyloid deposits, altered astroglial and microglial responses and elevation of CSF markers of neurodegeneration. Those observations were associated with increased TSPO and FDG-PET brain signals and a hyperactivity phenotype as the animals aged. DISCUSSION Our findings demonstrate that fibrillar Aβ in microglia is associated with lipid dyshomeostasis consistent with lysosomal dysfunction and foam cell phenotypes as well as profound immuno-metabolic perturbations, opening new avenues to further investigate metabolic pathways at play in microglia responding to AD-relevant pathogenesis. The in-depth characterization of pathological hallmarks of AD in this novel and open-access mouse model should serve as a resource for the scientific community to investigate disease-relevant biology.
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Affiliation(s)
- Dan Xia
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Steve Lianoglou
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Thomas Sandmann
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Meredith Calvert
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Jung H. Suh
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Elliot Thomsen
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Jason Dugas
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Michelle E. Pizzo
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Sarah L. DeVos
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Timothy K. Earr
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Chia-Ching Lin
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Sonnet Davis
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Connie Ha
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Amy Wing-Sze Leung
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Hoang Nguyen
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Roni Chau
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Ernie Yulyaningsih
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Isabel Lopez
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Hilda Solanoy
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Shababa T. Masoud
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Chun-chi Liang
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Karin Lin
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Giuseppe Astarita
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Nathalie Khoury
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Joy Yu Zuchero
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Robert G. Thorne
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
- Department of Pharmaceutics, University of Minnesota, 9-177 Weaver-Densford Hall, 308 Harvard St. SE, Minneapolis, MN 55455 USA
| | - Kevin Shen
- Gladstone Institute of Neurological Disease, San Francisco, CA 94158 USA
- Department of Neurology, University of California, San Francisco, CA 94158 USA
| | - Stephanie Miller
- Gladstone Institute of Neurological Disease, San Francisco, CA 94158 USA
- Department of Neurology, University of California, San Francisco, CA 94158 USA
| | - Jorge J. Palop
- Gladstone Institute of Neurological Disease, San Francisco, CA 94158 USA
- Department of Neurology, University of California, San Francisco, CA 94158 USA
| | | | | | | | | | - Selina Hummel
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Johannes Gnörich
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Karin Wind
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Lea Kunze
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Artem Zatcepin
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Matthias Brendel
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Michael Willem
- Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany
| | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
- Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig- Maximilians-Universität, München, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Daniel Barnett
- Appel Alzheimer’s Disease Research Institute, Weill Cornell Medicine, New York, NY USA
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY USA
- Neuroscience Graduate Program, Weill Cornell Medicine, New York, NY USA
| | - Till S. Zimmer
- Appel Alzheimer’s Disease Research Institute, Weill Cornell Medicine, New York, NY USA
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY USA
| | - Anna G. Orr
- Appel Alzheimer’s Disease Research Institute, Weill Cornell Medicine, New York, NY USA
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY USA
- Neuroscience Graduate Program, Weill Cornell Medicine, New York, NY USA
| | - Kimberly Scearce-Levie
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Joseph W. Lewcock
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Gilbert Di Paolo
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
| | - Pascal E. Sanchez
- Denali Therapeutics, Inc., 161 Oyster Point Blvd, South San Francisco, California, 94080 USA
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23
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Saggu S, Chen Y, Chen L, Pizarro D, Pati S, Law WJ, McMahon L, Jiao K, Wang Q. A peptide blocking the ADORA1-neurabin interaction is anticonvulsant and inhibits epilepsy in an Alzheimer's model. JCI Insight 2022; 7:155002. [PMID: 35674133 PMCID: PMC9220929 DOI: 10.1172/jci.insight.155002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 04/20/2022] [Indexed: 11/17/2022] Open
Abstract
Epileptic seizures are common sequelae of stroke, acute brain injury, and chronic neurodegenerative diseases, including Alzheimer's disease (AD), and cannot be effectively controlled in approximately 40% of patients, necessitating the development of novel therapeutic agents. Activation of the A1 receptor (A1R) by endogenous adenosine is an intrinsic mechanism to self-terminate seizures and protect neurons from excitotoxicity. However, targeting A1R for neurological disorders has been hindered by side effects associated with its broad expression outside the nervous system. Here we aim to target the neural-specific A1R/neurabin/regulator of G protein signaling 4 (A1R/neurabin/RGS4) complex that dictates A1R signaling strength and response outcome in the brain. We developed a peptide that blocks the A1R-neurabin interaction to enhance A1R activity. Intracerebroventricular or i.n. administration of this peptide shows marked protection against kainate-induced seizures and neuronal death. Furthermore, in an AD mouse model with spontaneous seizures, nasal delivery of this blocking peptide reduces epileptic spike frequency. Significantly, the anticonvulsant and neuroprotective effects of this peptide are achieved through enhanced A1R function in response to endogenous adenosine in the brain, thus, avoiding side effects associated with A1R activation in peripheral tissues and organs. Our study informs potentially new anti-seizure therapy applicable to epilepsy and other neurological illness with comorbid seizures.
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Affiliation(s)
- Shalini Saggu
- Departments of Cell, Developmental and Integrative Biology
| | - Yunjia Chen
- Departments of Cell, Developmental and Integrative Biology
| | - Liping Chen
- Departments of Cell, Developmental and Integrative Biology
| | | | | | - Wen Jing Law
- Departments of Cell, Developmental and Integrative Biology
| | - Lori McMahon
- Departments of Cell, Developmental and Integrative Biology
| | - Kai Jiao
- Department of Genetics, University of Alabama at Birmingham, Alabama, USA
| | - Qin Wang
- Departments of Cell, Developmental and Integrative Biology
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24
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Tok S, Maurin H, Delay C, Crauwels D, Manyakov NV, Van Der Elst W, Moechars D, Drinkenburg WHIM. Neurophysiological effects of human-derived pathological tau conformers in the APPKM670/671NL.PS1/L166P amyloid mouse model of Alzheimer's disease. Sci Rep 2022; 12:7784. [PMID: 35546164 PMCID: PMC9094605 DOI: 10.1038/s41598-022-11582-1] [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: 12/30/2021] [Accepted: 04/19/2022] [Indexed: 11/09/2022] Open
Abstract
Alzheimer’s Disease (AD) is a neurodegenerative disease characterized by two main pathological hallmarks: amyloid plaques and intracellular tau neurofibrillary tangles. However, a majority of studies focus on the individual pathologies and seldom on the interaction between the two pathologies. Herein, we present the longitudinal neuropathological and neurophysiological effects of a combined amyloid-tau model by hippocampal seeding of human-derived tau pathology in the APP.PS1/L166P amyloid animal model. We statistically assessed both neurophysiological and pathological changes using linear mixed modelling to determine if factors such as the age at which animals were seeded, genotype, seeding or buffer, brain region where pathology was quantified, and time-post injection differentially affect these outcomes. We report that AT8-positive tau pathology progressively develops and is facilitated by the amount of amyloid pathology present at the time of injection. The amount of AT8-positive tau pathology was influenced by the interaction of age at which the animal was injected, genotype, and time after injection. Baseline pathology-related power spectra and Higuchi Fractal Dimension (HFD) score alterations were noted in APP.PS1/L166P before any manipulations were performed, indicating a baseline difference associated with genotype. We also report immediate localized hippocampal dysfunction in the electroencephalography (EEG) power spectra associated with tau seeding which returned to comparable levels at 1 month-post-injection. Longitudinal effects of seeding indicated that tau-seeded wild-type mice showed an increase in gamma power earlier than buffer control comparisons which was influenced by the age at which the animal was injected. A reduction of hippocampal broadband power spectra was noted in tau-seeded wild-type mice, but absent in APP.PS1 animals. HFD scores appeared to detect subtle effects associated with tau seeding in APP.PS1 animals, which was differentially influenced by genotype. Notably, while tau histopathological changes were present, a lack of overt longitudinal electrophysiological alterations was noted, particularly in APP.PS1 animals that feature both pathologies after seeding, reiterating and underscoring the difficulty and complexity associated with elucidating physiologically relevant and translatable biomarkers of Alzheimer’s Disease at the early stages of the disease.
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Affiliation(s)
- S Tok
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium. .,Faculty of Science and Engineering, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands.
| | - H Maurin
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - C Delay
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - D Crauwels
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - N V Manyakov
- Data Sciences, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - W Van Der Elst
- Quantitative Sciences Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - D Moechars
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium
| | - W H I M Drinkenburg
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340, Beerse, Belgium.,Faculty of Science and Engineering, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
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Reutzel M, Grewal R, Joppe A, Eckert GP. Age-Dependent Alterations of Cognition, Mitochondrial Function, and Beta-Amyloid Deposition in a Murine Model of Alzheimer’s Disease—A Longitudinal Study. Front Aging Neurosci 2022; 14:875989. [PMID: 35585868 PMCID: PMC9108248 DOI: 10.3389/fnagi.2022.875989] [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: 02/14/2022] [Accepted: 03/30/2022] [Indexed: 11/21/2022] Open
Abstract
Aging is the main risk factor for sporadic Alzheimer’s disease (AD), which is characterized by the cerebral deposition of β-amyloid peptides (Aβ) and cognitive decline. Mitochondrial dysfunction is also characteristic of the disease and represents a hallmark of both, aging and neurodegeneration. We longitudinally followed Aβ levels, cognition, and mitochondrial function in the same cohort of Thy1-APP751SL mice representing a murine model of AD. In the course of time, changes were most prominent at an age of 13 months including the latency time in the passive avoidance test, the activity of complexes I and IV of the mitochondrial respiration chain, and expression of genes related to mitochondrial biogenesis and synaptic plasticity including Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1-α), CAMP responsive element binding protein 1 (CREB1), and Synaptophysin 1 (SYP1). These changes occurred in parallel with massively increasing cerebral Aβ levels. Other parameters were changed in younger mice including the alteration rate in the Y-maze test and the nesting score when Aβ levels were not changed yet. The results are consistent in the cohort described. However, previous, non-longitudinal studies reported divergent time points for the occurrence of the parameters studied. These findings are discussed in light of the current results.
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Affiliation(s)
- Martina Reutzel
- Laboratory for Nutrition in Prevention and Therapy, Biomedical Research Center Seltersberg (BFS), Institute of Nutritional Sciences, Justus-Liebig-University Giessen, Giessen, Germany
| | - Rekha Grewal
- Laboratory for Nutrition in Prevention and Therapy, Biomedical Research Center Seltersberg (BFS), Institute of Nutritional Sciences, Justus-Liebig-University Giessen, Giessen, Germany
| | - Aljoscha Joppe
- Department of Biological Sciences & Cluster of Excellence Macromolecular Complexes, Institute for Molecular Biosciences, Johann Wolfgang Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Gunter P. Eckert
- Laboratory for Nutrition in Prevention and Therapy, Biomedical Research Center Seltersberg (BFS), Institute of Nutritional Sciences, Justus-Liebig-University Giessen, Giessen, Germany
- *Correspondence: Gunter P. Eckert,
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26
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Shao E, Chang CW, Li Z, Yu X, Ho K, Zhang M, Wang X, Simms J, Lo I, Speckart J, Holtzman J, Yu GQ, Roberson ED, Mucke L. TAU ablation in excitatory neurons and postnatal TAU knockdown reduce epilepsy, SUDEP, and autism behaviors in a Dravet syndrome model. Sci Transl Med 2022; 14:eabm5527. [PMID: 35476595 DOI: 10.1126/scitranslmed.abm5527] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intracellular accumulation of TAU aggregates is a hallmark of several neurodegenerative diseases. However, global genetic reduction of TAU is beneficial also in models of other brain disorders that lack such TAU pathology, suggesting a pathogenic role of nonaggregated TAU. Here, conditional ablation of TAU in excitatory, but not inhibitory, neurons reduced epilepsy, sudden unexpected death in epilepsy, overactivation of the phosphoinositide 3-kinase-AKT-mammalian target of rapamycin pathway, brain overgrowth (megalencephaly), and autism-like behaviors in a mouse model of Dravet syndrome, a severe epileptic encephalopathy of early childhood. Furthermore, treatment with a TAU-lowering antisense oligonucleotide, initiated on postnatal day 10, had similar therapeutic effects in this mouse model. Our findings suggest that excitatory neurons are the critical cell type in which TAU has to be reduced to counteract brain dysfunctions associated with Dravet syndrome and that overall cerebral TAU reduction could have similar benefits, even when initiated postnatally.
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Affiliation(s)
- Eric Shao
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Che-Wei Chang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Zhiyong Li
- Alzheimer's Disease Center, Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Xinxing Yu
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Kaitlyn Ho
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Michelle Zhang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Xin Wang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Jeffrey Simms
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Iris Lo
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Jessica Speckart
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Julia Holtzman
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Gui-Qiu Yu
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Erik D Roberson
- Alzheimer's Disease Center, Center for Neurodegeneration and Experimental Therapeutics, Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Lennart Mucke
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA.,Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94158, USA
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Krafft GA, Jerecic J, Siemers E, Cline EN. ACU193: An Immunotherapeutic Poised to Test the Amyloid β Oligomer Hypothesis of Alzheimer’s Disease. Front Neurosci 2022; 16:848215. [PMID: 35557606 PMCID: PMC9088393 DOI: 10.3389/fnins.2022.848215] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/02/2022] [Indexed: 12/26/2022] Open
Abstract
Alzheimer’s disease (AD) is an age-related neurodegenerative disease that affects 50 million people worldwide, with 10 million new cases occurring each year. The emotional and economic impacts of AD on patients and families are devastating. Approved treatments confer modest improvement in symptoms, and recently one treatment obtained accelerated approval from the United States Food and Drug Administration (FDA) and may have modest disease modifying benefit. Research over the past three decades has established a clear causal linkage between AD and elevated brain levels of amyloid β (Aβ) peptide, and substantial evidence now implicates soluble, non-fibrillar Aβ oligomers (AβOs) as the molecular assemblies directly responsible for AD-associated memory and cognitive failure and accompanying progressive neurodegeneration. The widely recognized linkage of elevated Aβ and AD spawned a comprehensive 20-year therapeutic campaign that focused primarily on two strategies – inhibition of the secretase enzymes responsible for Aβ production and clearance of Aβ peptide or amyloid plaques with Aβ-directed immunotherapeutics. Unfortunately, all clinical trials of secretase inhibitors were unsuccessful. Of the completed phase 3 immunotherapy programs, bapineuzumab (targeting amyloid plaque) and solanezumab (targeting Aβ monomers) were negative, and the crenezumab program (targeting Aβ monomers and to a small extent oligomers) was stopped for futility. Aducanumab (targeting amyloid plaques), which recently received FDA accelerated approval, had one positive and one negative phase 3 trial. More than 25 negative randomized clinical trials (RCTs) have evaluated Aβ-targeting therapeutics, yet none has directly evaluated whether selective blockage of disease-relevant AβOs can stop or reverse AD-associated cognitive decline. Here, we briefly summarize studies that establish the AD therapeutic rationale to target AβOs selectively, and we describe ACU193, the first AβO-selective immunotherapeutic to enter human clinical trials and the first positioned to test the AβO hypothesis of AD.
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Therapeutic potential of Nlrp1 inflammasome, Caspase-1, or Caspase-6 against Alzheimer disease cognitive impairment. Cell Death Differ 2022; 29:657-669. [PMID: 34625662 PMCID: PMC8901623 DOI: 10.1038/s41418-021-00881-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 11/08/2022] Open
Abstract
The sequential activation of Nucleotide-binding oligomerization domain, Leucine rich Repeat and Pyrin domain containing protein 1 (Nlrp1) inflammasome, Caspase-1 (Casp1), and Caspase-6 (Casp6) is implicated in primary human neuron cultures and Alzheimer Disease (AD) neurodegeneration. To validate the Nlrp1-Casp1-Casp6 pathway in vivo, the APPSwedish/Indiana J20 AD transgenic mouse model was generated on either a Nlrp1, Casp1 or Casp6 null genetic background and mice were studied at 4-5 months of age. Episodic memory deficits assessed with novel object recognition were normalized by genetic ablation of Nlrp1, Casp1, or Casp6 in J20 mice. Spatial learning deficits, assessed with the Barnes Maze, were normalized in genetically ablated J20, whereas memory recall was normalized in J20/Casp1-/- and J20/Casp6-/-, and improved in J20/Nlrp1-/- mice. Hippocampal CA1 dendritic spine density of the mushroom subtype was reduced in J20, and normalized in genetically ablated J20 mice. Reduced J20 hippocampal dentate gyrus and CA3 synaptophysin levels were normalized in genetically ablated J20. Increased Iba1+-microglia in the hippocampus and cortex of J20 brains were normalized by Casp1 and Casp6 ablation and reduced by Nlrp1 ablation. Increased pro-inflammatory cytokines, TNF-α and CXCL1, in the J20 hippocampus were normalized by Nlrp1 or Casp1 genetic ablation. CXCL1 was also normalized by Casp6 genetic ablation. IFN-γ was increased and total amyloid β peptide was decreased in genetically ablated Nlrp1, Casp1 or Casp6 J20 hippocampi. We conclude that Nlrp1, Casp1, or Casp6 are implicated in AD-related cognitive impairment, inflammation, and amyloidogenesis. These results indicate that Nlrp1, Casp1, and Casp6 represent rational therapeutic targets against cognitive impairment and inflammation in AD.
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Cope ZA, Murai T, Sukoff Rizzo SJ. Emerging Electroencephalographic Biomarkers to Improve Preclinical to Clinical Translation in Alzheimer’s Disease. Front Aging Neurosci 2022; 14:805063. [PMID: 35250541 PMCID: PMC8891809 DOI: 10.3389/fnagi.2022.805063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/26/2022] [Indexed: 11/18/2022] Open
Abstract
Continually emerging data indicate that sub-clinical, non-convulsive epileptiform activity is not only prevalent in Alzheimer’s disease (AD) but is detectable early in the course of the disease and predicts cognitive decline in both humans and animal models. Epileptiform activity and other electroencephalographic (EEG) measures may hold powerful, untapped potential to improve the translational validity of AD-related biomarkers in model animals ranging from mice, to rats, and non-human primates. In this review, we will focus on studies of epileptiform activity, EEG slowing, and theta-gamma coupling in preclinical models, with particular focus on its role in cognitive decline and relevance to AD. Here, each biomarker is described in the context of the contemporary literature and recent findings in AD relevant animal models are discussed.
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30
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Chen YY, Liu QP, An P, Jia M, Luan X, Tang JY, Zhang H. Ginsenoside Rd: A promising natural neuroprotective agent. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2022; 95:153883. [PMID: 34952508 DOI: 10.1016/j.phymed.2021.153883] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/05/2021] [Accepted: 12/05/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Neurological diseases seriously affect human health, which are arousing wider attention, and it is a great challenge to discover neuroprotective drugs with minimal side-effects and better efficacies. Natural agents derived from herbs or plants have become unparalleled resources for the discovery of novel drug candidates. Panax ginseng C. A. Meyer, a well-known herbal medicine in China, occupies a very important position in traditional Chinese medicines (TCMs) with a long history of clinical application. Ginsenoside Rd is the active compound in P. ginseng known to have broad-spectrum pharmacological effects to reduce neurological damage that can lead to neurological diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, depression, cognitive impairment, and cerebral ischemia. PURPOSE To review and discuss the effects and mechanisms of ginsenoside Rd in the treatment of neurological diseases. STUDY DESIGN & METHODS The related information was compiled by the major scientific databases, such as Chinese National Knowledge Infrastructure (CNKI), Elsevier, ScienceDirect, PubMed, SpringerLink, Web of Science, and GeenMedical. Using 'Ginsenoside Rd', 'Ginsenosides', 'Anti-inflammation', 'Antioxidant', 'Apoptosis' and 'Neuroprotection' as keywords, the correlated literature was extracted and conducted from the databases mentioned above. RESULTS Through summarizing the existing research progress, we found that the general effects of ginsenoside Rd are anti-inflammatory, antioxidant, anti-apoptosis, inhibition of Ca2+ influx and protection of mitochondria, and through these pathways, the compound can inhibit excitatory toxicity, regulate nerve growth factor, and promote nerve regeneration. CONCLUSION Ginsenoside Rd is a promising natural neuroprotective agent. This review would contribute to the future development of ginsenoside Rd as a novel clinical candidate drug for treating neurological diseases.
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Affiliation(s)
- Yu-Ying Chen
- Shanghai Frontiers Science Center of TCM Chemical Biology; Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Qiu-Ping Liu
- Shanghai Frontiers Science Center of TCM Chemical Biology; Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Pei An
- Shanghai Frontiers Science Center of TCM Chemical Biology; Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Min Jia
- College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Xin Luan
- Shanghai Frontiers Science Center of TCM Chemical Biology; Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
| | - Jian-Yuan Tang
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu 610072, China.
| | - Hong Zhang
- Shanghai Frontiers Science Center of TCM Chemical Biology; Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China.
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31
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Das M, Mao W, Shao E, Tamhankar S, Yu GQ, Yu X, Ho K, Wang X, Wang J, Mucke L. Interdependence of neural network dysfunction and microglial alterations in Alzheimer's disease-related models. iScience 2021; 24:103245. [PMID: 34755090 PMCID: PMC8561005 DOI: 10.1016/j.isci.2021.103245] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/27/2021] [Accepted: 10/05/2021] [Indexed: 11/26/2022] Open
Abstract
Nonconvulsive epileptiform activity and microglial alterations have been detected in people with Alzheimer's disease (AD) and related mouse models. However, the relationship between these abnormalities remains to be elucidated. We suppressed epileptiform activity by treatment with the antiepileptic drug levetiracetam or by genetic ablation of tau and found that these interventions reversed or prevented aberrant microglial gene expression in brain tissues of aged human amyloid precursor protein transgenic mice, which simulate several key aspects of AD. The most robustly modulated genes included multiple factors previously implicated in AD pathogenesis, including TREM2, the hypofunction of which increases disease risk. Genetic reduction of TREM2 exacerbated epileptiform activity after mice were injected with kainate. We conclude that AD-related epileptiform activity markedly changes the molecular profile of microglia, inducing both maladaptive and adaptive alterations in their activities. Increased expression of TREM2 seems to support microglial activities that counteract this type of network dysfunction.
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Affiliation(s)
- Melanie Das
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Wenjie Mao
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Eric Shao
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Soniya Tamhankar
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Gui-Qiu Yu
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Xinxing Yu
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Kaitlyn Ho
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Xin Wang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Jiaming Wang
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
| | - Lennart Mucke
- Gladstone Institute of Neurological Disease, Gladstone Institutes, San Francisco, CA 94158, USA
- Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94158, USA
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Das B, Singh N, Yao AY, Zhou J, He W, Hu X, Yan R. BACE1 controls synaptic function through modulating release of synaptic vesicles. Mol Psychiatry 2021; 26:6394-6410. [PMID: 34158621 PMCID: PMC8760050 DOI: 10.1038/s41380-021-01166-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 04/27/2021] [Accepted: 05/06/2021] [Indexed: 01/20/2023]
Abstract
BACE1 initiates production of β-amyloid peptides (Aβ), which is associated with cognitive dysfunction in Alzheimer's disease (AD) due to abnormal oligomerization and aggregation. While BACE1 inhibitors show strong reduction in Aβ deposition, they fail to improve cognitive function in patients, largely due to its role in synaptic function. We show that BACE1 is required for optimal release of synaptic vesicles. BACE1 deficiency or inhibition decreases synaptic vesicle docking in the synaptic active zones. Consistently, BACE1-null mice or mice treated with clinically tested BACE1 inhibitors Verubecestat and Lanabecestat exhibit severe reduction in hippocampal LTP and learning behaviors. To counterbalance this synaptic deficit, we discovered that BACE1-null mice treated with positive allosteric modulators (PAMs) of metabotropic glutamate receptor 1 (mGluR1), whose levels were reduced in BACE1-null mice and significantly improved long-term potentiation and cognitive behaviors. Similarly, mice treated with mGluR1 PAM showed significantly mitigated synaptic deficits caused by BACE1 inhibitors. Together, our data suggest that a therapy combining BACE1 inhibitors for reducing amyloid deposition and an mGluR1 PAM for counteracting BACE1-mediated synaptic deficits appears to be an effective approach for treating AD patients.
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Affiliation(s)
- Brati Das
- Department of Neuroscience, UConn Health, Farmington, CT, USA
| | - Neeraj Singh
- Department of Neuroscience, UConn Health, Farmington, CT, USA
| | - Annie Y Yao
- Department of Neuroscience, UConn Health, Farmington, CT, USA
| | - John Zhou
- Department of Neuroscience, UConn Health, Farmington, CT, USA
| | - Wanxia He
- Department of Neuroscience, UConn Health, Farmington, CT, USA
| | - Xiangyou Hu
- Department of Neuroscience, UConn Health, Farmington, CT, USA
| | - Riqiang Yan
- Department of Neuroscience, UConn Health, Farmington, CT, USA.
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Kreis A, Desloovere J, Suelves N, Pierrot N, Yerna X, Issa F, Schakman O, Gualdani R, de Clippele M, Tajeddine N, Kienlen-Campard P, Raedt R, Octave JN, Gailly P. Overexpression of wild-type human amyloid precursor protein alters GABAergic transmission. Sci Rep 2021; 11:17600. [PMID: 34475508 PMCID: PMC8413381 DOI: 10.1038/s41598-021-97144-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/13/2021] [Indexed: 02/07/2023] Open
Abstract
The function of the amyloid precursor protein (APP) is not fully understood, but its cleavage product amyloid beta (Aβ) together with neurofibrillary tangles constitute the hallmarks of Alzheimer's disease (AD). Yet, imbalance of excitatory and inhibitory neurotransmission accompanied by loss of synaptic functions, has been reported much earlier and independent of any detectable pathological markers. Recently, soluble APP fragments have been shown to bind to presynaptic GABAB receptors (GABABRs), subsequently decreasing the probability of neurotransmitter release. In this body of work, we were able to show that overexpression of wild-type human APP in mice (hAPPwt) causes early cognitive impairment, neuronal loss, and electrophysiological abnormalities in the absence of amyloid plaques and at very low levels of Aβ. hAPPwt mice exhibited neuronal overexcitation that was evident in EEG and increased long-term potentiation (LTP). Overexpression of hAPPwt did not alter GABAergic/glutamatergic receptor components or GABA production ability. Nonetheless, we detected a decrease of GABA but not glutamate that could be linked to soluble APP fragments, acting on presynaptic GABABRs and subsequently reducing GABA release. By using a specific presynaptic GABABR antagonist, we were able to rescue hyperexcitation in hAPPwt animals. Our results provide evidence that APP plays a crucial role in regulating inhibitory neurotransmission.
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Affiliation(s)
- Anna Kreis
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Jana Desloovere
- grid.5342.00000 0001 2069 7798Faculty of Medicine and Health Sciences, Universiteit Gent, C. Heymanslaan 10, 9000 Gent, Belgium
| | - Nuria Suelves
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Nathalie Pierrot
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Xavier Yerna
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Farah Issa
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Olivier Schakman
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Roberta Gualdani
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Marie de Clippele
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Nicolas Tajeddine
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
| | - Pascal Kienlen-Campard
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Robrecht Raedt
- grid.5342.00000 0001 2069 7798Faculty of Medicine and Health Sciences, Universiteit Gent, C. Heymanslaan 10, 9000 Gent, Belgium
| | - Jean-Noël Octave
- grid.7942.80000 0001 2294 713XAlzheimer Dementia Group, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53, 1200 Brussels, Belgium
| | - Philippe Gailly
- grid.7942.80000 0001 2294 713XLaboratory of Cell Physiology, Institute of Neuroscience, Université Catholique de Louvain, av. Mounier 53/B1.53.17, 1200 Brussels, Belgium
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Sáez-Orellana F, Leroy T, Ribeiro F, Kreis A, Leroy K, Lalloyer F, Baugé E, Staels B, Duyckaerts C, Brion JP, Gailly P, Octave JN, Pierrot N. Regulation of PPARα by APP in Alzheimer disease affects the pharmacological modulation of synaptic activity. JCI Insight 2021; 6:e150099. [PMID: 34228639 PMCID: PMC8410016 DOI: 10.1172/jci.insight.150099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/30/2021] [Indexed: 11/17/2022] Open
Abstract
Among genetic susceptibility loci associated with late-onset Alzheimer disease (LOAD), genetic polymorphisms identified in genes encoding lipid carriers led to the hypothesis that a disruption of lipid metabolism could promote disease progression. We previously reported that amyloid precursor protein (APP) involved in Alzheimer disease (AD) physiopathology impairs lipid synthesis needed for cortical networks' activity and that activation of peroxisome proliferator-activated receptor α (PPARα), a metabolic regulator involved in lipid metabolism, improves synaptic plasticity in an AD mouse model. These observations led us to investigate a possible correlation between PPARα function and full-length APP expression. Here, we report that PPARα expression and activation were inversely related to APP expression both in LOAD brains and in early-onset AD cases with a duplication of the APP gene, but not in control human brains. Moreover, human APP expression decreased PPARA expression and its related target genes in transgenic mice and in cultured cortical cells, while opposite results were observed in APP-silenced cortical networks. In cultured neurons, APP-mediated decrease or increase in synaptic activity was corrected by a PPARα-specific agonist and antagonist, respectively. APP-mediated control of synaptic activity was abolished following PPARα deficiency, indicating a key function of PPARα in this process.
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Affiliation(s)
| | | | | | - Anna Kreis
- Laboratory of Cell Physiology, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
| | - Karelle Leroy
- Laboratory of Histology and Neuropathology, Free University of Brussels, Brussels, Belgium
| | - Fanny Lalloyer
- University of Lille, INSERM, CHU Lille, Pasteur Institute of Lille, U1011, Lille, France
| | - Eric Baugé
- University of Lille, INSERM, CHU Lille, Pasteur Institute of Lille, U1011, Lille, France
| | - Bart Staels
- University of Lille, INSERM, CHU Lille, Pasteur Institute of Lille, U1011, Lille, France
| | - Charles Duyckaerts
- University of Sorbonne, Pitié-Salpêtrière University Hospital, and Paris Brain Institute, CNRS UMR7225, INSERM U1127, Paris, France
| | - Jean-Pierre Brion
- Laboratory of Histology and Neuropathology, Free University of Brussels, Brussels, Belgium
| | - Philippe Gailly
- Laboratory of Cell Physiology, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
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35
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Tok S, Ahnaou A, Drinkenburg W. Functional Neurophysiological Biomarkers of Early-Stage Alzheimer's Disease: A Perspective of Network Hyperexcitability in Disease Progression. J Alzheimers Dis 2021; 88:809-836. [PMID: 34420957 PMCID: PMC9484128 DOI: 10.3233/jad-210397] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Network hyperexcitability (NH) has recently been suggested as a potential neurophysiological indicator of Alzheimer’s disease (AD), as new, more accurate biomarkers of AD are sought. NH has generated interest as a potential indicator of certain stages in the disease trajectory and even as a disease mechanism by which network dysfunction could be modulated. NH has been demonstrated in several animal models of AD pathology and multiple lines of evidence point to the existence of NH in patients with AD, strongly supporting the physiological and clinical relevance of this readout. Several hypotheses have been put forward to explain the prevalence of NH in animal models through neurophysiological, biochemical, and imaging techniques. However, some of these hypotheses have been built on animal models with limitations and caveats that may have derived NH through other mechanisms or mechanisms without translational validity to sporadic AD patients, potentially leading to an erroneous conclusion of the underlying cause of NH occurring in patients with AD. In this review, we discuss the substantiation for NH in animal models of AD pathology and in human patients, as well as some of the hypotheses considering recently developed animal models that challenge existing hypotheses and mechanisms of NH. In addition, we provide a preclinical perspective on how the development of animal models incorporating AD-specific NH could provide physiologically relevant translational experimental data that may potentially aid the discovery and development of novel therapies for AD.
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Affiliation(s)
- Sean Tok
- Department of Neuroscience, Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium.,Groningen Institute for Evolutionary Life Sciences, Faculty of Science and Engineering, University of Groningen, The Netherlands
| | - Abdallah Ahnaou
- Department of Neuroscience, Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Wilhelmus Drinkenburg
- Department of Neuroscience, Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium.,Groningen Institute for Evolutionary Life Sciences, Faculty of Science and Engineering, University of Groningen, The Netherlands
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36
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Kim HR, Jang JH, Ham H, Choo SH, Park J, Kang SH, Hwangbo S, Jang H, Na DL, Seo SW, Baek JH, Kim HJ. A Case of Early-Onset Alzheimer's Disease Mimicking Schizophrenia in a Patient with Presenilin 1 Mutation (S170P). J Alzheimers Dis 2021; 83:1025-1031. [PMID: 34366354 DOI: 10.3233/jad-210650] [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] [Indexed: 11/15/2022]
Abstract
Atypical psychological symptoms frequently occur in early-onset Alzheimer's disease (EOAD), which makes it difficult to differentiate it from other psychiatric disorders. We report the case of a 28-year-old woman with EOAD, carrying a presenilin-1 mutation (S170P), who was initially misdiagnosed with schizophrenia because of prominent psychiatric symptoms in the first 1-2 years of the disease. Amyloid-β positron emission tomography (PET) showed remarkably high tracer uptake in the striatum and thalamus. Tau PET showed widespread cortical uptake and relatively low uptake in the subcortical and medial temporal regions. Our case advocates for considering EOAD diagnosis for young patients with psychiatric and atypical cognitive symptoms.
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Affiliation(s)
- Hang-Rai Kim
- Department of Neurology, Dongguk University Ilsan Hospital, Dongguk University College of Medicine, Goyang, Republic of Korea.,Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
| | - Ja Hyun Jang
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Honggi Ham
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea.,Department of Digital Health, SAIHST, Sungkyunkwan University, Samsung Medical Center, Seoul, Republic of Korea.,Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea
| | - Seung Ho Choo
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jeongho Park
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sung Hoon Kang
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea.,Department of Neurology, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Republic of Korea
| | - Song Hwangbo
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
| | - Hyemin Jang
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea
| | - Duk L Na
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea.,Stem Cell & Regenerative Medicine Institute, Samsung Medical Center, Seoul, Republic of Korea
| | - Sang Won Seo
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea.,Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
| | - Ji Hyun Baek
- Department of Psychiatry, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hee Jin Kim
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.,Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, Republic of Korea.,Department of Digital Health, SAIHST, Sungkyunkwan University, Samsung Medical Center, Seoul, Republic of Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
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37
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Romoli M, Sen A, Parnetti L, Calabresi P, Costa C. Amyloid-β: a potential link between epilepsy and cognitive decline. Nat Rev Neurol 2021; 17:469-485. [PMID: 34117482 DOI: 10.1038/s41582-021-00505-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2021] [Indexed: 02/05/2023]
Abstract
People with epilepsy - in particular, late-onset epilepsy of unknown aetiology - have an elevated risk of dementia, and seizures have been detected in the early stages of Alzheimer disease (AD), supporting the concept of an epileptic AD prodrome. However, the relationship between epilepsy and cognitive decline remains controversial, with substantial uncertainties about whether epilepsy drives cognitive decline or vice versa, and whether shared pathways underlie both conditions. Here, we review evidence that amyloid-β (Aβ) forms part of a shared pathway between epilepsy and cognitive decline, particularly in the context of AD. People with epilepsy show an increased burden of Aβ pathology in the brain, and Aβ-mediated epileptogenic alterations have been demonstrated in experimental studies, with evidence suggesting that Aβ pathology might already be pro-epileptogenic at the soluble stage, long before plaque deposition. We discuss the hypothesis that Aβ mediates - or is at least a major determinant of - a continuum spanning epilepsy and cognitive decline. Serial cognitive testing and assessment of Aβ levels might be worthwhile to stratify the risk of developing dementia in people with late-onset epilepsy. If seizures are a clinical harbinger of dementia, people with late-onset epilepsy could be an ideal group in which to implement preventive or therapeutic strategies to slow cognitive decline.
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Affiliation(s)
- Michele Romoli
- Neurology Clinic, Department of Medicine and Surgery, University of Perugia - S. Maria della Misericordia Hospital, Perugia, Italy.,Oxford Epilepsy Research Group, NIHR Biomedical Research Centre, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK.,Neurology and Stroke Unit, "Maurizio Bufalini" Hospital, Cesena, Italy.,IRCCS Istituto delle Scienze Neurologiche di Bologna, Neurologia e Rete Stroke Metropolitana, Ospedale Maggiore, Bologna, Italy
| | - Arjune Sen
- Oxford Epilepsy Research Group, NIHR Biomedical Research Centre, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Lucilla Parnetti
- Neurology Clinic, Department of Medicine and Surgery, University of Perugia - S. Maria della Misericordia Hospital, Perugia, Italy
| | - Paolo Calabresi
- Dipartimento di Neuroscienze, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario A. Gemelli, IRCCS, UOC Neurologia, Dipartimento di Scienze dell'Invecchiamento, Neurologiche, Ortopediche e della Testa-Collo, Rome, Italy
| | - Cinzia Costa
- Neurology Clinic, Department of Medicine and Surgery, University of Perugia - S. Maria della Misericordia Hospital, Perugia, Italy.
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38
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Jin N, Babiloni C, Drinkenburg WH, Hajós M, Nygaard HB, Tanila H. Recommendations for Preclinical Testing of Treatments Against Alzheimer's Disease-Related Epileptiform Spikes in Transgenic Rodent Models. J Alzheimers Dis 2021; 88:849-865. [PMID: 34092642 DOI: 10.3233/jad-210209] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Recent evidence suggests that about 30%of patients with mild to moderate Alzheimer's disease (AD) without a known diagnosis of epilepsy may display epileptiform spikes during electroencephalographic (EEG) recordings. These abnormal discharges occur predominantly during sleep and may be associated with accelerated disease progression. Subclinical spikes may represent a relevant target for clinical drug interventions, and there is a clear unmet need for preclinical testing of novel disease modifying agents in suitable animal models. Transgenic rodent models of AD pathology exhibit various forms of epileptiform EEG activity related to the abnormal levels of amyloid species in the brain. Among them, large-amplitude cortical and hippocampal EEG spikes in mouse and rat AD models may be reminiscent of the subclinical epileptiform EEG spikes recorded in some AD patients. This article reports the recommendations of a multidisciplinary panel of experts on optimal EEG markers and experimental designs to measure and report epileptiform activities and their response to symptomatic and disease-modifying drugs in transgenic AD model rodents. These recommendations may harmonize future preclinical EEG studies in the drug discovery research and may increase the comparability of experimental outcomes and their translational clinical value.
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Affiliation(s)
- Nanxiang Jin
- A. I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
| | - Claudio Babiloni
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Rome, Italy.,Hospital San Raffaele Cassino, Cassino (FR), Italy
| | - Wilhelmus H Drinkenburg
- Janssen Research & Development, Janssen Pharmaceutica NV, Beerse, Belgium.,Groningen Institute for Evolutionary Life Sciences, University of Groningen, The Netherlands
| | - Mihály Hajós
- Cognito Therapeutics, Cambridge, MA, USA.,Yale University School of Medicine, New Haven, CT, USA
| | - Haakon B Nygaard
- Division of Neurology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Heikki Tanila
- A. I. Virtanen Institute, University of Eastern Finland, Kuopio, Finland
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Phenotypic Differences between the Alzheimer's Disease-Related hAPP-J20 Model and Heterozygous Zbtb20 Knock-Out Mice. eNeuro 2021; 8:ENEURO.0089-21.2021. [PMID: 33833046 PMCID: PMC8121260 DOI: 10.1523/eneuro.0089-21.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/30/2021] [Accepted: 04/02/2021] [Indexed: 12/20/2022] Open
Abstract
Diverse gene products contribute to the pathogenesis of Alzheimer’s disease (AD). Experimental models have helped elucidate their mechanisms and impact on brain functions. Human amyloid precursor protein (hAPP) transgenic mice from line J20 (hAPP-J20 mice) are widely used to simulate key aspects of AD. However, they also carry an insertional mutation in noncoding sequence of one Zbtb20 allele, a gene involved in neural development. We demonstrate that heterozygous hAPP-J20 mice have reduced Zbtb20 expression in some AD-relevant brain regions, but not others, and that Zbtb20 levels are higher in hAPP-J20 mice than heterozygous Zbtb20 knock-out (Zbtb20+/–) mice. Whereas hAPP-J20 mice have premature mortality, severe deficits in learning and memory, other behavioral alterations, and prominent nonconvulsive epileptiform activity, Zbtb20+/– mice do not. Thus, the insertional mutation in hAPP-J20 mice does not ablate the affected Zbtb20 allele and is unlikely to account for the AD-like phenotype of this model.
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40
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Is γ-secretase a beneficial inactivating enzyme of the toxic APP C-terminal fragment C99? J Biol Chem 2021; 296:100489. [PMID: 33662398 PMCID: PMC8027268 DOI: 10.1016/j.jbc.2021.100489] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 02/26/2021] [Accepted: 02/26/2021] [Indexed: 12/12/2022] Open
Abstract
Genetic, biochemical, and anatomical grounds led to the proposal of the amyloid cascade hypothesis centered on the accumulation of amyloid beta peptides (Aβ) to explain Alzheimer's disease (AD) etiology. In this context, a bulk of efforts have aimed at developing therapeutic strategies seeking to reduce Aβ levels, either by blocking its production (γ- and β-secretase inhibitors) or by neutralizing it once formed (Aβ-directed immunotherapies). However, so far the vast majority of, if not all, clinical trials based on these strategies have failed, since they have not been able to restore cognitive function in AD patients, and even in many cases, they have worsened the clinical picture. We here propose that AD could be more complex than a simple Aβ-linked pathology and discuss the possibility that a way to reconcile undoubted genetic evidences linking processing of APP to AD and a consistent failure of Aβ-based clinical trials could be to envision the pathological contribution of the direct precursor of Aβ, the β-secretase-derived C-terminal fragment of APP, βCTF, also referred to as C99. In this review, we summarize scientific evidences pointing to C99 as an early contributor to AD and postulate that γ-secretase should be considered as not only an Aβ-generating protease, but also a beneficial C99-inactivating enzyme. In that sense, we discuss the limitations of molecules targeting γ-secretase and propose alternative strategies seeking to reduce C99 levels by other means and notably by enhancing its lysosomal degradation.
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