1
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Walker CK, Liu E, Greathouse KM, Adamson AB, Wilson JP, Poovey EH, Curtis KA, Muhammad HM, Weber AJ, Bennett DA, Seyfried NT, Gaiteri C, Herskowitz JH. Dendritic spine head diameter predicts episodic memory performance in older adults. SCIENCE ADVANCES 2024; 10:eadn5181. [PMID: 39110801 PMCID: PMC11305389 DOI: 10.1126/sciadv.adn5181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 07/02/2024] [Indexed: 08/10/2024]
Abstract
Episodic memory in older adults is varied and perceived to rely on numbers of synapses or dendritic spines. We analyzed 2157 neurons among 128 older individuals from the Religious Orders Study and Rush Memory and Aging Project. Analysis of 55,521 individual dendritic spines by least absolute shrinkage and selection operator regression and nested model cross-validation revealed that the dendritic spine head diameter in the temporal cortex, but not the premotor cortex, improved the prediction of episodic memory performance in models containing β amyloid plaque scores, neurofibrillary tangle pathology, and sex. These findings support the emerging hypothesis that, in the temporal cortex, synapse strength is more critical than quantity for memory in old age.
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Affiliation(s)
- Courtney K. Walker
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Evan Liu
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Kelsey M. Greathouse
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Ashley B. Adamson
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Julia P. Wilson
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Emily H. Poovey
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Kendall A. Curtis
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Hamad M. Muhammad
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Audrey J. Weber
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Nicholas T. Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Christopher Gaiteri
- Department of Psychiatry, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Jeremy H. Herskowitz
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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2
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Lykhmus O, Tzeng WY, Koval L, Uspenska K, Zirdum E, Kalashnyk O, Garaschuk O, Skok M. Impairment of brain function in a mouse model of Alzheimer's disease during the pre-depositing phase: The role of α7 nicotinic acetylcholine receptors. Biomed Pharmacother 2024; 178:117255. [PMID: 39116785 DOI: 10.1016/j.biopha.2024.117255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 07/24/2024] [Accepted: 08/02/2024] [Indexed: 08/10/2024] Open
Abstract
Alzheimer's disease (AD) is an age-dependent incurable neurodegenerative disorder accompanied by neuroinflammation, amyloid accumulation, and memory impairment. It begins decades before the first clinical symptoms appear, and identifying early biomarkers is key for developing disease-modifying therapies. We show now in a mouse model of AD that before any amyloid deposition the brains of 1.5-month-old mice contain increased levels of pro-inflammatory cytokines IL-1β and IL-6, decreased levels of nicotinic acetylcholine receptors (nAChRs) in the brain and brain mitochondria and increased amounts of α7 nAChR-bound Aβ1-42, along with impaired episodic memory and increased risk of apoptosis. Both acute (1-week-long) and chronic (4-month-long) treatments with α7-selective agonist PNU282987, starting at 1.5 months of age, were well tolerated. The acute treatment did not affect the levels of soluble Aβ1-42 but consistently upregulated the α7 nAChR expression, decreased the level of α7-Aβ1-42 complexes, and improved episodic memory of 1.5-month-old mice. The chronic treatment, covering the disease development phase, strongly upregulated the expression of all abundant brain nAChRs, reduced both free and α7-coupled Aβ1-42 within the brain, had anti-inflammatory and antiapoptotic effects, and potently upregulated cognition, thus identifying α7 nAChRs as both early biomarker and potent therapeutic target for fighting this devastating disease.
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Affiliation(s)
- Olena Lykhmus
- Palladin Institute of Biochemistry NAS of Ukraine, Kyiv, Ukraine
| | - Wen-Yu Tzeng
- Department of Neurophysiology, Institute of Physiology, University of Tübingen, Tübingen, Germany
| | - Lyudmyla Koval
- Palladin Institute of Biochemistry NAS of Ukraine, Kyiv, Ukraine
| | | | - Elizabeta Zirdum
- Department of Neurophysiology, Institute of Physiology, University of Tübingen, Tübingen, Germany
| | - Olena Kalashnyk
- Palladin Institute of Biochemistry NAS of Ukraine, Kyiv, Ukraine
| | - Olga Garaschuk
- Department of Neurophysiology, Institute of Physiology, University of Tübingen, Tübingen, Germany.
| | - Maryna Skok
- Palladin Institute of Biochemistry NAS of Ukraine, Kyiv, Ukraine
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3
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Zhuang D, Yu N, Han S, Zhang X, Ju C. The Kv7 channel opener Retigabine reduces neuropathology and alleviates behavioral deficits in APP/PS1 transgenic mice. Behav Brain Res 2024; 471:115137. [PMID: 38971432 DOI: 10.1016/j.bbr.2024.115137] [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: 03/22/2024] [Revised: 06/19/2024] [Accepted: 07/01/2024] [Indexed: 07/08/2024]
Abstract
Hyperexcitability of neuronal networks is central to the pathogenesis of Alzheimer's disease (AD). Pharmacological activation of Kv7 channels is an effective way to reduce neuronal firing. Our results showed that that pharmacologically activating the Kv7 channel with Retigabine (RTG) can alleviate cognitive impairment in mice without affecting spontaneous activity. RTG could also ameliorate damage to the Nissl bodies in cortex and hippocampal CA and DG regions in 9-month-old APP/PS1 mice. Additionally, RTG could reduce the Aβ plaque number in the hippocampus and cortex of both 6-month-old and 9-month-old mice. By recordings of electroencephalogram, we showed that a decrease in the number of abnormal discharges in the brains of the AD model mice when the Kv7 channel was opened. Moreover, Western blot analysis revealed a reduction in the expression of the p-Tau protein in both the hippocampus and cortex upon Kv7 channel opening. These findings suggest that Kv7 channel opener RTG may ameliorate cognitive impairment in AD, most likely by reducing brain excitability.
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Affiliation(s)
- Dongpei Zhuang
- Department of Pharmacology, School of Pharmacy, Qingdao University Qingdao Medical College, China.
| | - Nan Yu
- Department of Pharmacy, Qingdao Eighth People's Hospital, China.
| | - Shuo Han
- Department of Pharmacology, School of Pharmacy, Qingdao University Qingdao Medical College, China.
| | - Xinyao Zhang
- Department of Pharmacology, School of Pharmacy, Qingdao University Qingdao Medical College, China.
| | - Chuanxia Ju
- Department of Pharmacology, School of Pharmacy, Qingdao University Qingdao Medical College, China.
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4
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Chen M, Wang C, Lin Y, Chen Y, Xie W, Huang X, Zhang F, Fu C, Zhuang K, Zou T, Can D, Li H, Wu S, Luo C, Zhang J. Dorsal raphe nucleus-hippocampus serotonergic circuit underlies the depressive and cognitive impairments in 5×FAD male mice. Transl Neurodegener 2024; 13:34. [PMID: 39044270 PMCID: PMC11267773 DOI: 10.1186/s40035-024-00425-w] [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: 12/04/2023] [Accepted: 06/19/2024] [Indexed: 07/25/2024] Open
Abstract
BACKGROUND Depressive symptoms often occur in patients with Alzheimer's disease (AD) and exacerbate the pathogenesis of AD. However, the neural circuit mechanisms underlying the AD-associated depression remain unclear. The serotonergic system plays crucial roles in both AD and depression. METHODS We used a combination of in vivo trans-synaptic circuit-dissecting anatomical approaches, chemogenetic manipulations, optogenetic manipulations, pharmacological methods, behavioral testing, and electrophysiological recording to investigate dorsal raphe nucleus serotonergic circuit in AD-associated depression in AD mouse model. RESULTS We found that the activity of dorsal raphe nucleus serotonin neurons (DRN5-HT) and their projections to the dorsal hippocampal CA1 (dCA1) terminals (DRN5-HT-dCA1CaMKII) both decreased in brains of early 5×FAD mice. Chemogenetic or optogenetic activation of the DRN5-HT-dCA1CaMKII neural circuit attenuated the depressive symptoms and cognitive impairments in 5×FAD mice through serotonin receptor 1B (5-HT1BR) and 4 (5-HT4R). Pharmacological activation of 5-HT1BR or 5-HT4R attenuated the depressive symptoms and cognitive impairments in 5×FAD mice by regulating the DRN5-HT-dCA1CaMKII neural circuit to improve synaptic plasticity. CONCLUSIONS These findings provide a new mechanistic connection between depression and AD and provide potential pharmaceutical prevention targets for AD.
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Affiliation(s)
- Meiqin Chen
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, College of Basic Medicine, Hebei Medical University, Shijiazhuang, 050017, China
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Chenlu Wang
- Department of Anesthesiology, First Affiliated Hospital of Xiamen University, Xiamen, 361000, China
| | - Yinan Lin
- Department of Anesthesiology, First Affiliated Hospital of Xiamen University, Xiamen, 361000, China
| | - Yanbing Chen
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Wenting Xie
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Xiaoting Huang
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Fan Zhang
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, College of Basic Medicine, Hebei Medical University, Shijiazhuang, 050017, China
| | - Congrui Fu
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, College of Basic Medicine, Hebei Medical University, Shijiazhuang, 050017, China
| | - Kai Zhuang
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Tingting Zou
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Dan Can
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Huifang Li
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China
| | - Shengxi Wu
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, 710032, China
| | - Ceng Luo
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, 710032, China
| | - Jie Zhang
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, College of Basic Medicine, Hebei Medical University, Shijiazhuang, 050017, China.
- Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, 361102, China.
- Department of Neurology, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, 610054, China.
- Institute of Neuroscience, Fujian Medical University, Fuzhou, 350004, China.
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5
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Uchiumi O, Zou J, Yamaki S, Hori Y, Ono M, Yamamoto R, Kato N. Disruption of sphingomyelin synthase 2 gene alleviates cognitive impairment in a mouse model of Alzheimer's disease. Brain Res 2024; 1835:148934. [PMID: 38609029 DOI: 10.1016/j.brainres.2024.148934] [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: 02/15/2024] [Revised: 03/28/2024] [Accepted: 04/09/2024] [Indexed: 04/14/2024]
Abstract
The membrane raft accommodates the key enzymes synthesizing amyloid β (Aβ). One of the two characteristic components of the membrane raft, cholesterol, is well known to promote the key enzymes that produce amyloid-β (Aβ) and exacerbate Alzheimer's disease (AD) pathogenesis. Given that the raft is a physicochemical platform for the sound functioning of embedded bioactive proteins, the other major lipid component sphingomyelin may also be involved in AD. Here we knocked out the sphingomyelin synthase 2 gene (SMS2) in 3xTg AD model mice by hybridization, yielding SMS2KO mice (4S mice). The novel object recognition test in 9/10-month-old 4S mice showed that cognitive impairment in 3xTg mice was alleviated by SMS2KO, though performance in the Morris water maze (MWM) was not improved. The tail suspension test detected a depressive trait in 4S mice, which may have hindered the manifestation of performance in the wet, stressful environment of MWM. In the hippocampal CA1, hyperexcitability in 3xTg was also found alleviated by SMS2KO. In the hippocampal dentate gyrus of 4S mice, the number of neurons positive with intracellular Aβ or its precursor proteins, the hallmark of young 3xTg mice, is reduced to one-third, suggesting an SMS2KO-led suppression of syntheses of those peptides in the dentate gyrus. Although we previously reported that large-conductance calcium-activated potassium (BK) channels are suppressed in 3xTg mice and their recovery relates to cognitive amelioration, no changes occurred by hybridization. Sphingomyelin in the membrane raft may serve as a novel target for AD drugs.
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Affiliation(s)
- Osamu Uchiumi
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan
| | - Jingyu Zou
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan; First Affiliated Hospital, China Medical University, Shenyang 110001, China
| | - Sachiko Yamaki
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan
| | - Yoshie Hori
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan
| | - Munenori Ono
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan
| | - Ryo Yamamoto
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan
| | - Nobuo Kato
- Department of Physiology, Kanazawa Medical University, Ishikawa 920-0293, Japan.
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6
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Lee R, Kim G, Kim S. Co-activation of selective nicotinic acetylcholine receptor subtypes is required to reverse hippocampal network dysfunction and prevent fear memory loss in Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.08.602576. [PMID: 39026693 PMCID: PMC11257460 DOI: 10.1101/2024.07.08.602576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Alzheimer's disease (AD) is the most common form of dementia with no known cause and cure. Research suggests that a reduction of GABAergic inhibitory interneurons' activity in the hippocampus by beta-amyloid peptide (Aβ) is a crucial trigger for cognitive impairment in AD via hyperexcitability. Therefore, enhancing hippocampal inhibition is thought to be protective against AD. However, hippocampal inhibitory cells are highly diverse, and these distinct interneuron subtypes differentially regulate hippocampal inhibitory circuits and cognitive processes. Moreover, Aβ unlikely affects all subtypes of inhibitory interneurons in the hippocampus equally. Hence, identifying the affected interneuron subtypes in AD to enhance hippocampal inhibition optimally is conceptually and practically challenging. We have previously found that Aβ selectively binds to two of the three major hippocampal nicotinic acetylcholine receptor (nAChR) subtypes, α7- and α4β2-nAChRs, but not α3β4-nAChRs, and inhibits these two receptors in cultured hippocampal inhibitory interneurons to decrease their activity, leading to hyperexcitation and synaptic dysfunction in excitatory neurons. We have also revealed that co-activation of α7- and α4β2-nAChRs is required to reverse the Aβ-induced adverse effects in hippocampal excitatory neurons. Here, we discover that α7- and α4β2-nAChRs predominantly control the nicotinic cholinergic signaling and neuronal activity in hippocampal parvalbumin-positive (PV+) and somatostatin-positive (SST+) inhibitory interneurons, respectively. Furthermore, we reveal that co-activation of these receptors is necessary to reverse hippocampal network dysfunction and fear memory loss in the amyloid pathology model mice. We thus suggest that co-activation of PV+ and SST+ cells is a novel strategy to reverse hippocampal dysfunction and cognitive decline in AD.
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7
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Zott B, Nästle L, Grienberger C, Unger F, Knauer MM, Wolf C, Keskin-Dargin A, Feuerbach A, Busche MA, Skerra A, Konnerth A. β-amyloid monomer scavenging by an anticalin protein prevents neuronal hyperactivity in mouse models of Alzheimer's Disease. Nat Commun 2024; 15:5819. [PMID: 38987287 PMCID: PMC11237084 DOI: 10.1038/s41467-024-50153-y] [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: 01/25/2023] [Accepted: 07/02/2024] [Indexed: 07/12/2024] Open
Abstract
Hyperactivity mediated by synaptotoxic β-amyloid (Aβ) oligomers is one of the earliest forms of neuronal dysfunction in Alzheimer's disease. In the search for a preventive treatment strategy, we tested the effect of scavenging Aβ peptides before Aβ plaque formation. Using in vivo two-photon calcium imaging and SF-iGluSnFR-based glutamate imaging in hippocampal slices, we demonstrate that an Aβ binding anticalin protein (Aβ-anticalin) can suppress early neuronal hyperactivity and synaptic glutamate accumulation in the APP23xPS45 mouse model of β-amyloidosis. Our results suggest that the sole targeting of Aβ monomers is sufficient for the hyperactivity-suppressing effect of the Aβ-anticalin at early disease stages. Biochemical and neurophysiological analyses indicate that the Aβ-anticalin-dependent depletion of naturally secreted Aβ monomers interrupts their aggregation to neurotoxic oligomers and, thereby, reverses early neuronal and synaptic dysfunctions. Thus, our results suggest that Aβ monomer scavenging plays a key role in the repair of neuronal function at early stages of AD.
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Affiliation(s)
- Benedikt Zott
- Institute of Neuroscience, Technical University of Munich, Munich, Germany.
- Department of Neuroradiology, MRI hospital of the Technical University of Munich, Munich, Germany.
- TUM Institute for Advanced Study, Garching, Germany.
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
| | - Lea Nästle
- Chair of Biological Chemistry, Technical University of Munich, Freising, Germany
| | - Christine Grienberger
- Institute of Neuroscience, Technical University of Munich, Munich, Germany
- Department of Biology and Volen National Center of Complex Systems, Brandeis University, Waltham, MA, USA
| | - Felix Unger
- Institute of Neuroscience, Technical University of Munich, Munich, Germany
- Department of Neuroradiology, MRI hospital of the Technical University of Munich, Munich, Germany
- TUM Institute for Advanced Study, Garching, Germany
| | - Manuel M Knauer
- Institute of Neuroscience, Technical University of Munich, Munich, Germany
| | - Christian Wolf
- Institute of Neuroscience, Technical University of Munich, Munich, Germany
- Department of Neuroradiology, MRI hospital of the Technical University of Munich, Munich, Germany
| | | | - Anna Feuerbach
- Chair of Biological Chemistry, Technical University of Munich, Freising, Germany
| | - Marc Aurel Busche
- Institute of Neuroscience, Technical University of Munich, Munich, Germany
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Arne Skerra
- Chair of Biological Chemistry, Technical University of Munich, Freising, Germany.
| | - Arthur Konnerth
- Institute of Neuroscience, Technical University of Munich, Munich, Germany.
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
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8
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Rodriguez-Rodriguez P, Arroyo-Garcia LE, Tsagkogianni C, Li L, Wang W, Végvári Á, Salas-Allende I, Plautz Z, Cedazo-Minguez A, Sinha SC, Troyanskaya O, Flajolet M, Yao V, Roussarie JP. A cell autonomous regulator of neuronal excitability modulates tau in Alzheimer's disease vulnerable neurons. Brain 2024; 147:2384-2399. [PMID: 38462574 PMCID: PMC11224620 DOI: 10.1093/brain/awae051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/12/2024] [Accepted: 01/19/2024] [Indexed: 03/12/2024] Open
Abstract
Neurons from layer II of the entorhinal cortex (ECII) are the first to accumulate tau protein aggregates and degenerate during prodromal Alzheimer's disease. Gaining insight into the molecular mechanisms underlying this vulnerability will help reveal genes and pathways at play during incipient stages of the disease. Here, we use a data-driven functional genomics approach to model ECII neurons in silico and identify the proto-oncogene DEK as a regulator of tau pathology. We show that epigenetic changes caused by Dek silencing alter activity-induced transcription, with major effects on neuronal excitability. This is accompanied by the gradual accumulation of tau in the somatodendritic compartment of mouse ECII neurons in vivo, reactivity of surrounding microglia, and microglia-mediated neuron loss. These features are all characteristic of early Alzheimer's disease. The existence of a cell-autonomous mechanism linking Alzheimer's disease pathogenic mechanisms in the precise neuron type where the disease starts provides unique evidence that synaptic homeostasis dysregulation is of central importance in the onset of tau pathology in Alzheimer's disease.
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Affiliation(s)
| | | | - Christina Tsagkogianni
- Department of Neurobiology Care Sciences and Society, Karolinska Institutet, 17 164, Solna, Sweden
| | - Lechuan Li
- Department of Computer Science, Rice University, Houston, TX 77004, USA
| | - Wei Wang
- Bioinformatics Resource Center, The Rockefeller University, New York, NY 10065, USA
| | - Ákos Végvári
- Division of Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17 164, Solna, Sweden
| | - Isabella Salas-Allende
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, NY 10065, USA
| | - Zakary Plautz
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, NY 10065, USA
| | - Angel Cedazo-Minguez
- Department of Neurobiology Care Sciences and Society, Karolinska Institutet, 17 164, Solna, Sweden
| | - Subhash C Sinha
- Helen and Robert Appel Alzheimer’s Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Olga Troyanskaya
- Department of Computer Science, Princeton University, Princeton, NJ 08540, USA
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
- Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, NY 10010, USA
| | - Marc Flajolet
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, NY 10065, USA
| | - Vicky Yao
- Division of Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17 164, Solna, Sweden
| | - Jean-Pierre Roussarie
- Department of Anatomy & Neurobiology, Boston University Chobanian and Avedisian School of Medicine, Boston, MA 02118, USA
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9
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Tabuena DR, Jang SS, Grone B, Yip O, Aery Jones EA, Blumenfeld J, Liang Z, Koutsodendris N, Rao A, Ding L, Zhang AR, Hao Y, Xu Q, Yoon SY, Leon SD, Huang Y, Zilberter M. Neuronal APOE4-induced Early Hippocampal Network Hyperexcitability in Alzheimer's Disease Pathogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.28.555153. [PMID: 37693533 PMCID: PMC10491126 DOI: 10.1101/2023.08.28.555153] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The full impact of apolipoprotein E4 (APOE4), the strongest genetic risk factor for Alzheimer's disease (AD), on neuronal and network function remains unclear. We found hippocampal region-specific network hyperexcitability in young APOE4 knock-in (E4-KI) mice which predicted cognitive deficits at old age. Network hyperexcitability in young E4-KI mice was mediated by hippocampal region-specific subpopulations of smaller and hyperexcitable neurons that were eliminated by selective removal of neuronal APOE4. Aged E4-KI mice exhibited hyperexcitable granule cells, a progressive inhibitory deficit, and E/I imbalance in the dentate gyrus, exacerbating hippocampal hyperexcitability. Single-nucleus RNA-sequencing revealed neuronal cell type-specific and age-dependent transcriptomic changes, including Nell2 overexpression in E4-KI mice. Reducing Nell2 expression in specific neuronal types of E4-KI mice with CRISPRi rescued their abnormal excitability phenotypes, implicating Nell2 overexpression as a cause of APOE4-induced hyperexcitability. These findings highlight the early transcriptomic and electrophysiological alterations underlying APOE4-induced hippocampal network dysfunction and its contribution to AD pathogenesis with aging.
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10
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Rajani RM, Ellingford R, Hellmuth M, Harris SS, Taso OS, Graykowski D, Lam FKW, Arber C, Fertan E, Danial JSH, Swire M, Lloyd M, Giovannucci TA, Bourdenx M, Klenerman D, Vassar R, Wray S, Sala Frigerio C, Busche MA. Selective suppression of oligodendrocyte-derived amyloid beta rescues neuronal dysfunction in Alzheimer's disease. PLoS Biol 2024; 22:e3002727. [PMID: 39042667 PMCID: PMC11265669 DOI: 10.1371/journal.pbio.3002727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Accepted: 07/01/2024] [Indexed: 07/25/2024] Open
Abstract
Reduction of amyloid beta (Aβ) has been shown to be effective in treating Alzheimer's disease (AD), but the underlying assumption that neurons are the main source of pathogenic Aβ is untested. Here, we challenge this prevailing belief by demonstrating that oligodendrocytes are an important source of Aβ in the human brain and play a key role in promoting abnormal neuronal hyperactivity in an AD knock-in mouse model. We show that selectively suppressing oligodendrocyte Aβ production improves AD brain pathology and restores neuronal function in the mouse model in vivo. Our findings suggest that targeting oligodendrocyte Aβ production could be a promising therapeutic strategy for treating AD.
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Affiliation(s)
- Rikesh M. Rajani
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Robert Ellingford
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Mariam Hellmuth
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Samuel S. Harris
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Orjona S. Taso
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - David Graykowski
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Francesca Kar Wey Lam
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Charles Arber
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London, United Kingdom
| | - Emre Fertan
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
- UK Dementia Research Institute at University of Cambridge, Cambridge, United Kingdom
| | - John S. H. Danial
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
- UK Dementia Research Institute at University of Cambridge, Cambridge, United Kingdom
- School of Physics and Astronomy, University of St Andrews, St. Andrews, United Kingdom
| | - Matthew Swire
- Wolfson Institute for Biomedical Research, University College London, London, United Kingdom
| | - Marcus Lloyd
- Wolfson Institute for Biomedical Research, University College London, London, United Kingdom
| | - Tatiana A. Giovannucci
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London, United Kingdom
| | - Mathieu Bourdenx
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - David Klenerman
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
- UK Dementia Research Institute at University of Cambridge, Cambridge, United Kingdom
| | - Robert Vassar
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Selina Wray
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London, United Kingdom
| | - Carlo Sala Frigerio
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
| | - Marc Aurel Busche
- UK Dementia Research Institute at UCL, University College London, London, United Kingdom
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11
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Mizuta K, Sato M. Multiphoton imaging of hippocampal neural circuits: techniques and biological insights into region-, cell-type-, and pathway-specific functions. NEUROPHOTONICS 2024; 11:033406. [PMID: 38464393 PMCID: PMC10923542 DOI: 10.1117/1.nph.11.3.033406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/31/2024] [Accepted: 02/06/2024] [Indexed: 03/12/2024]
Abstract
Significance The function of the hippocampus in behavior and cognition has long been studied primarily through electrophysiological recordings from freely moving rodents. However, the application of optical recording methods, particularly multiphoton fluorescence microscopy, in the last decade or two has dramatically advanced our understanding of hippocampal function. This article provides a comprehensive overview of techniques and biological findings obtained from multiphoton imaging of hippocampal neural circuits. Aim This review aims to summarize and discuss the recent technical advances in multiphoton imaging of hippocampal neural circuits and the accumulated biological knowledge gained through this technology. Approach First, we provide a brief overview of various techniques of multiphoton imaging of the hippocampus and discuss its advantages, drawbacks, and associated key innovations and practices. Then, we review a large body of findings obtained through multiphoton imaging by region (CA1 and dentate gyrus), cell type (pyramidal neurons, inhibitory interneurons, and glial cells), and cellular compartment (dendrite and axon). Results Multiphoton imaging of the hippocampus is primarily performed under head-fixed conditions and can reveal detailed mechanisms of circuit operation owing to its high spatial resolution and specificity. As the hippocampus lies deep below the cortex, its imaging requires elaborate methods. These include imaging cannula implantation, microendoscopy, and the use of long-wavelength light sources. Although many studies have focused on the dorsal CA1 pyramidal cells, studies of other local and inter-areal circuitry elements have also helped provide a more comprehensive picture of the information processing performed by the hippocampal circuits. Imaging of circuit function in mouse models of Alzheimer's disease and other brain disorders such as autism spectrum disorder has also contributed greatly to our understanding of their pathophysiology. Conclusions Multiphoton imaging has revealed much regarding region-, cell-type-, and pathway-specific mechanisms in hippocampal function and dysfunction in health and disease. Future technological advances will allow further illustration of the operating principle of the hippocampal circuits via the large-scale, high-resolution, multimodal, and minimally invasive imaging.
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Affiliation(s)
- Kotaro Mizuta
- RIKEN BDR, Kobe, Japan
- New York University Abu Dhabi, Department of Biology, Abu Dhabi, United Arab Emirates
| | - Masaaki Sato
- Hokkaido University Graduate School of Medicine, Department of Neuropharmacology, Sapporo, Japan
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12
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Linsley JW, Reisine T, Finkbeiner S. Three dimensional and four dimensional live imaging to study mechanisms of progressive neurodegeneration. J Biol Chem 2024; 300:107433. [PMID: 38825007 PMCID: PMC11261153 DOI: 10.1016/j.jbc.2024.107433] [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: 08/30/2023] [Revised: 05/20/2024] [Accepted: 05/26/2024] [Indexed: 06/04/2024] Open
Abstract
Neurodegenerative diseases are complex and progressive, posing challenges to their study and understanding. Recent advances in microscopy imaging technologies have enabled the exploration of neurons in three spatial dimensions (3D) over time (4D). When applied to 3D cultures, tissues, or animals, these technologies can provide valuable insights into the dynamic and spatial nature of neurodegenerative diseases. This review focuses on the use of imaging techniques and neurodegenerative disease models to study neurodegeneration in 4D. Imaging techniques such as confocal microscopy, two-photon microscopy, miniscope imaging, light sheet microscopy, and robotic microscopy offer powerful tools to visualize and analyze neuronal changes over time in 3D tissue. Application of these technologies to in vitro models of neurodegeneration such as mouse organotypic culture systems and human organoid models provide versatile platforms to study neurodegeneration in a physiologically relevant context. Additionally, use of 4D imaging in vivo, including in mouse and zebrafish models of neurodegenerative diseases, allows for the investigation of early dysfunction and behavioral changes associated with neurodegeneration. We propose that these studies have the power to overcome the limitations of two-dimensional monolayer neuronal cultures and pave the way for improved understanding of the dynamics of neurodegenerative diseases and the development of effective therapeutic strategies.
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Affiliation(s)
- Jeremy W Linsley
- Center for Systems and Therapeutics, Gladstone Institutes, San Francisco, California, USA; Operant Biopharma, San Francisco, California, USA
| | - Terry Reisine
- Independent Scientific Consultant, Santa Cruz, California, USA
| | - Steven Finkbeiner
- Center for Systems and Therapeutics, Gladstone Institutes, San Francisco, California, USA; Operant Biopharma, San Francisco, California, USA; Taube/Koret Center for Neurodegenerative Disease, Gladstone Institutes, San Francisco, California, USA; Departments of Neurology and Physiology, University of California, San Francisco, California, USA; Neuroscience Graduate Program, University of California, San Francisco, California, USA; Biomedical Sciences Graduate Program, University of California, San Francisco, California, USA.
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13
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De Paolis ML, Paoletti I, Zaccone C, Capone F, D'Amelio M, Krashia P. Transcranial alternating current stimulation (tACS) at gamma frequency: an up-and-coming tool to modify the progression of Alzheimer's Disease. Transl Neurodegener 2024; 13:33. [PMID: 38926897 PMCID: PMC11210106 DOI: 10.1186/s40035-024-00423-y] [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: 01/08/2024] [Accepted: 05/24/2024] [Indexed: 06/28/2024] Open
Abstract
The last decades have witnessed huge efforts devoted to deciphering the pathological mechanisms underlying Alzheimer's Disease (AD) and to testing new drugs, with the recent FDA approval of two anti-amyloid monoclonal antibodies for AD treatment. Beyond these drug-based experimentations, a number of pre-clinical and clinical trials are exploring the benefits of alternative treatments, such as non-invasive stimulation techniques on AD neuropathology and symptoms. Among the different non-invasive brain stimulation approaches, transcranial alternating current stimulation (tACS) is gaining particular attention due to its ability to externally control gamma oscillations. Here, we outline the current knowledge concerning the clinical efficacy, safety, ease-of-use and cost-effectiveness of tACS on early and advanced AD, applied specifically at 40 Hz frequency, and also summarise pre-clinical results on validated models of AD and ongoing patient-centred trials.
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Affiliation(s)
- Maria Luisa De Paolis
- Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21 - 00128, Rome, Italy
| | - Ilaria Paoletti
- Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21 - 00128, Rome, Italy
| | - Claudio Zaccone
- Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21 - 00128, Rome, Italy
| | - Fioravante Capone
- Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21 - 00128, Rome, Italy
- Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200 - 00128, Rome, Italy
| | - Marcello D'Amelio
- Department of Medicine and Surgery, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21 - 00128, Rome, Italy.
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, Via del Fosso Di Fiorano, 64 - 00143, Rome, Italy.
| | - Paraskevi Krashia
- Department of Experimental Neurosciences, IRCCS Santa Lucia Foundation, Via del Fosso Di Fiorano, 64 - 00143, Rome, Italy
- Department of Sciences and Technologies for Sustainable Development and One Health, Università Campus Bio-Medico Di Roma, Via Alvaro del Portillo, 21 - 00128, Rome, Italy
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14
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Nabizadeh F. Disruption in functional networks mediated tau spreading in Alzheimer's disease. Brain Commun 2024; 6:fcae198. [PMID: 38978728 PMCID: PMC11227975 DOI: 10.1093/braincomms/fcae198] [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: 01/18/2024] [Revised: 04/27/2024] [Accepted: 06/07/2024] [Indexed: 07/10/2024] Open
Abstract
Alzheimer's disease may be conceptualized as a 'disconnection syndrome', characterized by the breakdown of neural connectivity within the brain as a result of amyloid-beta plaques, tau neurofibrillary tangles and other factors leading to progressive degeneration and shrinkage of neurons, along with synaptic dysfunction. It has been suggested that misfolded tau proteins spread through functional connections (known as 'prion-like' properties of tau). However, the local effect of tau spreading on the synaptic function and communication between regions is not well understood. I aimed to investigate how the spreading of tau aggregates through connections can locally influence functional connectivity. In total, the imaging data of 211 participants including 117 amyloid-beta-negative non-demented and 94 amyloid-beta-positive non-demented participants were recruited from the Alzheimer's Disease Neuroimaging Initiative. Furthermore, normative resting-state functional MRI connectomes were used to model tau spreading through functional connections, and functional MRI of the included participants was used to determine the effect of tau spreading on functional connectivity. I found that lower functional connectivity to tau epicentres is associated with tau spreading through functional connections in both amyloid-beta-negative and amyloid-beta-positive participants. Also, amyloid-beta-PET in tau epicentres mediated the association of tau spreading and functional connectivity to epicentres suggesting a partial mediating effect of amyloid-beta deposition in tau epicentres on the local effect of tau spreading on functional connectivity. My findings provide strong support for the notion that tau spreading through connection is locally associated with disrupted functional connectivity between tau epicentre and non-epicentre regions independent of amyloid-beta pathology. Also, I defined several groups based on the relationship between tau spreading and functional disconnection, which provides quantitative assessment to investigate susceptibility or resilience to functional disconnection related to tau spreading. I showed that amyloid-beta, other copathologies and the apolipoprotein E epsilon 4 allele can be a leading factor towards vulnerability to tau relative functional disconnection.
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Affiliation(s)
- Fardin Nabizadeh
- School of Medicine, Iran University of Medical Sciences, Tehran 441265421414, Iran
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15
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Moguilner SG, Berezuk C, Bender AC, Pellerin KR, Gomperts SN, Cash SS, Sarkis RA, Lam AD. Sleep functional connectivity, hyperexcitability, and cognition in Alzheimer's disease. Alzheimers Dement 2024; 20:4234-4249. [PMID: 38764252 PMCID: PMC11180941 DOI: 10.1002/alz.13861] [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: 02/12/2024] [Revised: 03/29/2024] [Accepted: 04/01/2024] [Indexed: 05/21/2024]
Abstract
INTRODUCTION Sleep disturbances are common in Alzheimer's disease (AD) and may reflect pathologic changes in brain networks. To date, no studies have examined changes in sleep functional connectivity (FC) in AD or their relationship with network hyperexcitability and cognition. METHODS We assessed electroencephalogram (EEG) sleep FC in 33 healthy controls, 36 individuals with AD without epilepsy, and 14 individuals with AD and epilepsy. RESULTS AD participants showed increased gamma connectivity in stage 2 sleep (N2), which was associated with longitudinal cognitive decline. Network hyperexcitability in AD was associated with a distinct sleep connectivity signature, characterized by decreased N2 delta connectivity and reversal of several connectivity changes associated with AD. Machine learning algorithms using sleep connectivity features accurately distinguished diagnostic groups and identified "fast cognitive decliners" among study participants who had AD. DISCUSSION Our findings reveal changes in sleep functional networks associated with cognitive decline in AD and may have implications for disease monitoring and therapeutic development. HIGHLIGHTS Brain functional connectivity (FC) in Alzheimer's disease is altered during sleep. Sleep FC measures correlate with cognitive decline in AD. Network hyperexcitability in AD has a distinct sleep connectivity signature.
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Affiliation(s)
- Sebastian G. Moguilner
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
| | - Courtney Berezuk
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
| | - Alex C. Bender
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
| | - Kyle R. Pellerin
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
| | - Stephen N. Gomperts
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
| | - Sydney S. Cash
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
| | - Rani A. Sarkis
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyBrigham and Women's HospitalBostonMassachusettsUSA
| | - Alice D. Lam
- Department of NeurologyHarvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General HospitalBostonMassachusettsUSA
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16
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Su M, Xuan E, Sun X, Pan G, Li D, Zheng H, Zhang YW, Li Y. Synaptic adhesion molecule protocadherin-γC5 mediates β-amyloid-induced neuronal hyperactivity and cognitive deficits in Alzheimer's disease. J Neurochem 2024; 168:1060-1079. [PMID: 38308496 DOI: 10.1111/jnc.16066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 02/04/2024]
Abstract
Neuronal hyperactivity induced by β-amyloid (Aβ) is an early pathological feature in Alzheimer's disease (AD) and contributes to cognitive decline in AD progression. However, the underlying mechanisms are still unclear. Here, we revealed that Aβ increased the expression level of synaptic adhesion molecule protocadherin-γC5 (Pcdh-γC5) in a Ca2+-dependent manner, associated with aberrant elevation of synapses in both Aβ-treated neurons in vitro and the cortex of APP/PS1 mice in vivo. By using Pcdhgc5 gene knockout mice, we demonstrated the critical function of Pcdh-γC5 in regulating neuronal synapse formation, synaptic transmission, and cognition. To further investigate the role of Pcdh-γC5 in AD pathogenesis, the aberrantly enhanced expression of Pcdh-γC5 in the brain of APP/PS1 mice was knocked down by shRNA. Downregulation of Pcdh-γC5 efficiently rescued neuronal hyperactivity and impaired cognition in APP/PS1 mice. Our findings revealed the pathophysiological role of Pcdh-γC5 in mediating Aβ-induced neuronal hyperactivity and cognitive deficits in AD and identified a novel mechanism underlying AD pathogenesis.
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Affiliation(s)
- Min Su
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Erying Xuan
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Xiangyi Sun
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Gaojie Pan
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Dandan Li
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Honghua Zheng
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Yun-Wu Zhang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Yanfang Li
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
- Shenzhen Research Institute of Xiamen University, Shenzhen, Guangdong, China
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17
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Li H, Zhao Z, Fassini A, Lee HK, Green RJ, Gomperts SN. Impaired Hippocampal Reactivation Preceding Robust Aβ Deposition in a Model of Alzheimer's Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.26.595168. [PMID: 38853978 PMCID: PMC11160633 DOI: 10.1101/2024.05.26.595168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Current therapeutic strategies for Alzheimer's disease (AD) target amyloid-beta (Aβ) fibrils and high molecular weight protofibrils associated with plaques, but other bioactive species may directly contribute to neural systems failure in AD. Employing hippocampal electrophysiological recordings and dynamic calcium imaging across the sleep-wake cycle in young mice expressing human Aβ and Aβ oligomers, we reveal marked impairments of hippocampal function long before amyloid plaques predominate. In slow wave sleep (SWS), Aβ increased the proportion of hypoactive cells and reduced place-cell reactivation. During awake behavior, Aβ impaired theta-gamma phase-amplitude coupling (PAC) and drove excessive synchronization of place cell calcium fluctuations with hippocampal theta. Remarkably, the on-line impairment of hippocampal theta-gamma PAC correlated with the SWS impairment of place-cell reactivation. Together, these results identify toxic effects of Aβ on memory encoding and consolidation processes before robust plaque deposition and support targeting soluble Aβ-related species to treat and prevent AD.
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Affiliation(s)
- Hanyan Li
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Zhuoyang Zhao
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Aline Fassini
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Han K. Lee
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Reese J. Green
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Stephen N. Gomperts
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
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18
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Karimani F, Asgari Taei A, Abolghasemi-Dehaghani MR, Safari MS, Dargahi L. Impairment of entorhinal cortex network activity in Alzheimer's disease. Front Aging Neurosci 2024; 16:1402573. [PMID: 38882526 PMCID: PMC11176617 DOI: 10.3389/fnagi.2024.1402573] [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: 03/17/2024] [Accepted: 05/20/2024] [Indexed: 06/18/2024] Open
Abstract
The entorhinal cortex (EC) stands out as a critical brain region affected in the early phases of Alzheimer's disease (AD), with some of the disease's pathological processes originating from this area, making it one of the most crucial brain regions in AD. Recent research highlights disruptions in the brain's network activity, characterized by heightened excitability and irregular oscillations, may contribute to cognitive impairment. These disruptions are proposed not only as potential therapeutic targets but also as early biomarkers for AD. In this paper, we will begin with a review of the anatomy and function of EC, highlighting its selective vulnerability in AD. Subsequently, we will discuss the disruption of EC network activity, exploring changes in excitability and neuronal oscillations in this region during AD and hypothesize that, considering the advancements in neuromodulation techniques, addressing the disturbances in the network activity of the EC could offer fresh insights for both the diagnosis and treatment of AD.
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Affiliation(s)
- Farnaz Karimani
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Afsaneh Asgari Taei
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Mir-Shahram Safari
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Leila Dargahi
- Neurobiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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19
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L'esperance OJ, McGhee J, Davidson G, Niraula S, Smith AS, Sosunov A, Yan SS, Subramanian J. Functional connectivity favors aberrant visual network c-Fos expression accompanied by cortical synapse loss in a mouse model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.05.522900. [PMID: 36712054 PMCID: PMC9881957 DOI: 10.1101/2023.01.05.522900] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
While Alzheimer's disease (AD) has been extensively studied with a focus on cognitive networks, sensory network dysfunction has received comparatively less attention despite compelling evidence of its significance in both Alzheimer's disease patients and mouse models. We recently found that neurons in the primary visual cortex of an AD mouse model expressing human amyloid protein precursor with the Swedish and Indiana mutations (hAPP mutations) exhibit aberrant c-Fos expression and altered synaptic structures at a pre-amyloid plaque stage. However, it is unclear whether aberrant c-Fos expression and synaptic pathology vary across the broader visual network and to what extent c-Fos abnormality in the cortex is inherited through functional connectivity. Using both sexes of 4-6-month AD model mice with hAPP mutations (J20[PDGF-APPSw, Ind]), we found that cortical regions of the visual network show aberrant c-Fos expression and impaired experience-dependent modulation while subcortical regions do not. Interestingly, the average network-wide functional connectivity strength of a brain region in wild type (WT) mice significantly predicts its aberrant c-Fos expression, which in turn correlates with impaired experience-dependent modulation in the AD model. Using in vivo two-photon and ex vivo imaging of presynaptic termini, we observed a subtle yet selective weakening of excitatory cortical synapses in the visual cortex. Intriguingly, the change in the size distribution of cortical boutons in the AD model is downscaled relative to those in WT mice, suggesting that synaptic weakening may reflect an adaptation to aberrant activity. Our observations suggest that cellular and synaptic abnormalities in the AD model represent a maladaptive transformation of the baseline physiological state seen in WT conditions rather than entirely novel and unrelated manifestations.
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20
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Bonifazi G, Luchena C, Gaminde-Blasco A, Ortiz-Sanz C, Capetillo-Zarate E, Matute C, Alberdi E, De Pittà M. A nonlinear meccano for Alzheimer's emergence by amyloid β-mediated glutamatergic hyperactivity. Neurobiol Dis 2024; 194:106473. [PMID: 38493903 DOI: 10.1016/j.nbd.2024.106473] [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: 10/26/2023] [Revised: 03/10/2024] [Accepted: 03/10/2024] [Indexed: 03/19/2024] Open
Abstract
The pathophysiological process of Alzheimer's disease (AD) is believed to begin many years before the formal diagnosis of AD dementia. This protracted preclinical phase offers a crucial window for potential therapeutic interventions, yet its comprehensive characterization remains elusive. Accumulating evidence suggests that amyloid-β (Aβ) may mediate neuronal hyperactivity in circuit dysfunction in the early stages of AD. At the same time, neural activity can also facilitate Aβ accumulation through intricate feed-forward interactions, complicating elucidating the conditions governing Aβ-dependent hyperactivity and its diagnostic utility. In this study, we use biophysical modeling to shed light on such conditions. Our analysis reveals that the inherently nonlinear nature of the underlying molecular interactions can give rise to the emergence of various modes of hyperactivity. This diversity in the mechanisms of hyperactivity may ultimately account for a spectrum of AD manifestations.
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Affiliation(s)
- Giulio Bonifazi
- Basque Center for Applied Mathematics, Alameda Mazarredo 14, Bilbao 48009, Bizkaia, Spain; Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto M5T 0S8, ON, Canada
| | - Celia Luchena
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain
| | - Adhara Gaminde-Blasco
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain
| | - Carolina Ortiz-Sanz
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain
| | - Estibaliz Capetillo-Zarate
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain
| | - Carlos Matute
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain
| | - Elena Alberdi
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED), Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain
| | - Maurizio De Pittà
- Basque Center for Applied Mathematics, Alameda Mazarredo 14, Bilbao 48009, Bizkaia, Spain; Department of Neurosciences, University of the Basque Country, Barrio Sarriena, s/n, Leioa 48940, Bizkaia, Spain; Krembil Research Institute, University Health Network, 60 Leonard Ave, Toronto M5T 0S8, ON, Canada; Department of Physiology, University of Toronto, 1 King's College Circle, Toronto M5S 1A8, ON, Canada.
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21
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Nelson ED, Tippani M, Ramnauth AD, Divecha HR, Miller RA, Eagles NJ, Pattie EA, Kwon SH, Bach SV, Kaipa UM, Yao J, Kleinman JE, Collado-Torres L, Han S, Maynard KR, Hyde TM, Martinowich K, Page SC, Hicks SC. An integrated single-nucleus and spatial transcriptomics atlas reveals the molecular landscape of the human hippocampus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.590643. [PMID: 38712198 PMCID: PMC11071618 DOI: 10.1101/2024.04.26.590643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
The hippocampus contains many unique cell types, which serve the structure's specialized functions, including learning, memory and cognition. These cells have distinct spatial topography, morphology, physiology, and connectivity, highlighting the need for transcriptome-wide profiling strategies that retain cytoarchitectural organization. Here, we generated spatially-resolved transcriptomics (SRT) and single-nucleus RNA-sequencing (snRNA-seq) data from adjacent tissue sections of the anterior human hippocampus across ten adult neurotypical donors. We defined molecular profiles for hippocampal cell types and spatial domains. Using non-negative matrix factorization and transfer learning, we integrated these data to define gene expression patterns within the snRNA-seq data and infer the expression of these patterns in the SRT data. With this approach, we leveraged existing rodent datasets that feature information on circuit connectivity and neural activity induction to make predictions about axonal projection targets and likelihood of ensemble recruitment in spatially-defined cellular populations of the human hippocampus. Finally, we integrated genome-wide association studies with transcriptomic data to identify enrichment of genetic components for neurodevelopmental, neuropsychiatric, and neurodegenerative disorders across cell types, spatial domains, and gene expression patterns of the human hippocampus. To make this comprehensive molecular atlas accessible to the scientific community, both raw and processed data are freely available, including through interactive web applications.
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22
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Bonzanni M, Braga A, Saito T, Saido TC, Tesco G, Haydon PG. Adenosine deficiency facilitates CA1 synaptic hyperexcitability in the presymptomatic phase of a knock in mouse model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.24.590882. [PMID: 38712028 PMCID: PMC11071633 DOI: 10.1101/2024.04.24.590882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
The disease's trajectory of Alzheimer's disease (AD) is associated with and worsened by hippocampal hyperexcitability. Here we show that during the asymptomatic stage in a knock in mouse model of Alzheimer's disease (APPNL-G-F/NL-G-F; APPKI), hippocampal hyperactivity occurs at the synaptic compartment, propagates to the soma and is manifesting at low frequencies of stimulation. We show that this aberrant excitability is associated with a deficient adenosine tone, an inhibitory neuromodulator, driven by reduced levels of CD39/73 enzymes, responsible for the extracellular ATP-to-adenosine conversion. Both pharmacologic (adenosine kinase inhibitor) and non-pharmacologic (ketogenic diet) restorations of the adenosine tone successfully normalize hippocampal neuronal activity. Our results demonstrated that neuronal hyperexcitability during the asymptomatic stage of a KI model of Alzheimer's disease originated at the synaptic compartment and is associated with adenosine deficient tone. These results extend our comprehension of the hippocampal vulnerability associated with the asymptomatic stage of Alzheimer's disease.
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Affiliation(s)
- Mattia Bonzanni
- Department of Neuroscience, Tufts University, Boston, MA, USA
| | - Alice Braga
- Department of Neuroscience, Tufts University, Boston, MA, USA
- Current address: Centre for Cardiovascular and 811 Metabolic Neuroscience, Department of Neuroscience, Physiology & Pharmacology, University College London, London, WC1E 6BT, UK
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi 467-8601, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | | | - Philip G Haydon
- Department of Neuroscience, Tufts University, Boston, MA, USA
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23
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Moguilner S, Herzog R, Perl YS, Medel V, Cruzat J, Coronel C, Kringelbach M, Deco G, Ibáñez A, Tagliazucchi E. Biophysical models applied to dementia patients reveal links between geographical origin, gender, disease duration, and loss of neural inhibition. Alzheimers Res Ther 2024; 16:79. [PMID: 38605416 PMCID: PMC11008050 DOI: 10.1186/s13195-024-01449-0] [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: 11/06/2023] [Accepted: 04/02/2024] [Indexed: 04/13/2024]
Abstract
BACKGROUND The hypothesis of decreased neural inhibition in dementia has been sparsely studied in functional magnetic resonance imaging (fMRI) data across patients with different dementia subtypes, and the role of social and demographic heterogeneities on this hypothesis remains to be addressed. METHODS We inferred regional inhibition by fitting a biophysical whole-brain model (dynamic mean field model with realistic inter-areal connectivity) to fMRI data from 414 participants, including patients with Alzheimer's disease, behavioral variant frontotemporal dementia, and controls. We then investigated the effect of disease condition, and demographic and clinical variables on the local inhibitory feedback, a variable related to the maintenance of balanced neural excitation/inhibition. RESULTS Decreased local inhibitory feedback was inferred from the biophysical modeling results in dementia patients, specific to brain areas presenting neurodegeneration. This loss of local inhibition correlated positively with years with disease, and showed differences regarding the gender and geographical origin of the patients. The model correctly reproduced known disease-related changes in functional connectivity. CONCLUSIONS Results suggest a critical link between abnormal neural and circuit-level excitability levels, the loss of grey matter observed in dementia, and the reorganization of functional connectivity, while highlighting the sensitivity of the underlying biophysical mechanism to demographic and clinical heterogeneities in the patient population.
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Affiliation(s)
- Sebastian Moguilner
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile
- Global Brain Health Institute (GBHI), University of California San Francisco (UCSF), 1207 1651 4th St, 3rd Floor, San Francisco, CA, 94143, USA
- Cognitive Neuroscience Center (CNC), Universidad de San Andrés, Vito Dumas 284, B1644BID, Buenos Aires, VIC, Argentina
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 25 Shattuck St, Boston, MA, 02115, USA
- Trinity College Dublin, Lloyd Building Trinity College Dublin, Dublin, D02 PN40, Ireland
| | - Rubén Herzog
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile
| | - Yonatan Sanz Perl
- Cognitive Neuroscience Center (CNC), Universidad de San Andrés, Vito Dumas 284, B1644BID, Buenos Aires, VIC, Argentina
- National Scientific and Technical Research Council (CONICET), Godoy Cruz 2290, CABA, 1425, Argentina
- Institute of Applied and Interdisciplinary Physics and Department of Physics, University of Buenos Aires, Pabellón 1, Ciudad Universitaria, CABA, 1428, Argentina
- Center for Brain and Cognition, Computational Neuroscience Group, Universitat Pompeu Fabra, Plaça de La Mercè, 10-12, Barcelona, 08002, Spain
| | - Vicente Medel
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Universidad de Valparaíso, Harrington 287, Valparaíso, 2381850, Chile
| | - Josefina Cruzat
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile
| | - Carlos Coronel
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile
| | - Morten Kringelbach
- Centre for Eudaimonia and Human Flourishing, Linacre College, University of Oxford, St.Cross Rd, Oxford, OX1 3JA, UK
- Department of Psychiatry, University of Oxford, Warneford Hospital, Warneford Ln, Headington, Oxford, OX3 7JX, UK
- Center for Music in the Brain, Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Blvd. 82, Aarhus, 8200, Denmark
| | - Gustavo Deco
- Center for Brain and Cognition, Computational Neuroscience Group, Universitat Pompeu Fabra, Plaça de La Mercè, 10-12, Barcelona, 08002, Spain
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, Leipzig, 04103, Germany
- Institució Catalana de Recerca I Estudis Avancats (ICREA), Passeig de Lluís Companys, 23, Barcelona, 08010, Spain
- Turner Institute for Brain and Mental Health, Monash University, 770 Blackburn Rd,, Clayton, VIC, 3168, Australia
| | - Agustín Ibáñez
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile.
- Global Brain Health Institute (GBHI), University of California San Francisco (UCSF), 1207 1651 4th St, 3rd Floor, San Francisco, CA, 94143, USA.
- Cognitive Neuroscience Center (CNC), Universidad de San Andrés, Vito Dumas 284, B1644BID, Buenos Aires, VIC, Argentina.
- Trinity College Institute of Neuroscience, Trinity College Dublin, 152 - 160 Pearse St, Dublin, D02 R590, Ireland.
- Trinity College Dublin, Lloyd Building Trinity College Dublin, Dublin, D02 PN40, Ireland.
| | - Enzo Tagliazucchi
- Latin American Brain Health (BrainLat), Universidad Adolfo Ibáñez, Av. Diag. Las Torres 2640, Santiago Región Metropolitana, Peñalolén, 7941169, Chile.
- Cognitive Neuroscience Center (CNC), Universidad de San Andrés, Vito Dumas 284, B1644BID, Buenos Aires, VIC, Argentina.
- National Scientific and Technical Research Council (CONICET), Godoy Cruz 2290, CABA, 1425, Argentina.
- Institute of Applied and Interdisciplinary Physics and Department of Physics, University of Buenos Aires, Pabellón 1, Ciudad Universitaria, CABA, 1428, Argentina.
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24
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Prabhu P, Morise H, Kudo K, Beagle A, Mizuiri D, Syed F, Kotegar KA, Findlay A, Miller BL, Kramer JH, Rankin KP, Garcia PA, Kirsch HE, Vossel K, Nagarajan SS, Ranasinghe KG. Abnormal gamma phase-amplitude coupling in the parahippocampal cortex is associated with network hyperexcitability in Alzheimer's disease. Brain Commun 2024; 6:fcae121. [PMID: 38665964 PMCID: PMC11043655 DOI: 10.1093/braincomms/fcae121] [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: 11/22/2023] [Revised: 03/08/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
While animal models of Alzheimer's disease (AD) have shown altered gamma oscillations (∼40 Hz) in local neural circuits, the low signal-to-noise ratio of gamma in the resting human brain precludes its quantification via conventional spectral estimates. Phase-amplitude coupling (PAC) indicating the dynamic integration between the gamma amplitude and the phase of low-frequency (4-12 Hz) oscillations is a useful alternative to capture local gamma activity. In addition, PAC is also an index of neuronal excitability as the phase of low-frequency oscillations that modulate gamma amplitude, effectively regulates the excitability of local neuronal firing. In this study, we sought to examine the local neuronal activity and excitability using gamma PAC, within brain regions vulnerable to early AD pathophysiology-entorhinal cortex and parahippocampus, in a clinical population of patients with AD and age-matched controls. Our clinical cohorts consisted of a well-characterized cohort of AD patients (n = 50; age, 60 ± 8 years) with positive AD biomarkers, and age-matched, cognitively unimpaired controls (n = 35; age, 63 ± 5.8 years). We identified the presence or the absence of epileptiform activity in AD patients (AD patients with epileptiform activity, AD-EPI+, n = 20; AD patients without epileptiform activity, AD-EPI-, n = 30) using long-term electroencephalography (LTM-EEG) and 1-hour long magnetoencephalography (MEG) with simultaneous EEG. Using the source reconstructed MEG data, we computed gamma PAC as the coupling between amplitude of the gamma frequency (30-40 Hz) with phase of the theta (4-8 Hz) and alpha (8-12 Hz) frequency oscillations, within entorhinal and parahippocampal cortices. We found that patients with AD have reduced gamma PAC in the left parahippocampal cortex, compared to age-matched controls. Furthermore, AD-EPI+ patients showed greater reductions in gamma PAC than AD-EPI- in bilateral parahippocampal cortices. In contrast, entorhinal cortices did not show gamma PAC abnormalities in patients with AD. Our findings demonstrate the spatial patterns of altered gamma oscillations indicating possible region-specific manifestations of network hyperexcitability within medial temporal lobe regions vulnerable to AD pathophysiology. Greater deficits in AD-EPI+ suggests that reduced gamma PAC is a sensitive index of network hyperexcitability in AD patients. Collectively, the current results emphasize the importance of investigating the role of neural circuit hyperexcitability in early AD pathophysiology and explore its potential as a modifiable contributor to AD pathobiology.
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Affiliation(s)
- Pooja Prabhu
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
- Department of Data science and Computer Applications, Manipal Institute of Technology, Manipal 576104, India
| | - Hirofumi Morise
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
- Medical Imaging Business Center, Ricoh Company Ltd., Kanazawa 920-0177, Japan
| | - Kiwamu Kudo
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
- Medical Imaging Business Center, Ricoh Company Ltd., Kanazawa 920-0177, Japan
| | - Alexander Beagle
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Danielle Mizuiri
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
| | - Faatimah Syed
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Karunakar A Kotegar
- Department of Data science and Computer Applications, Manipal Institute of Technology, Manipal 576104, India
| | - Anne Findlay
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
| | - Bruce L Miller
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Joel H Kramer
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Katherine P Rankin
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Paul A Garcia
- Epilepsy Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Heidi E Kirsch
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
- Epilepsy Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
| | - Keith Vossel
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
- Mary S. Easton Center for Alzheimer’s Research and Care, Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Srikantan S Nagarajan
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94158, USA
| | - Kamalini G Ranasinghe
- Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA
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25
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B Szabo A, Sayegh F, Gauzin S, Lejards C, Guiard B, Valton L, Verret L, Rampon C, Dahan L. No major effect of dopamine receptor 1/5 antagonist SCH-23390 on epileptic activity in the Tg2576 mouse model of amyloidosis. Eur J Neurosci 2024; 59:1558-1566. [PMID: 38308520 DOI: 10.1111/ejn.16268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 12/19/2023] [Accepted: 01/14/2024] [Indexed: 02/04/2024]
Abstract
The excitation-inhibition imbalance manifesting as epileptic activities in Alzheimer's disease is gaining more and more attention, and several potentially involved cellular and molecular pathways are currently under investigation. Based on in vitro studies, dopamine D1-type receptors in the anterior cingulate cortex and the hippocampus have been proposed to participate in this peculiar co-morbidity in mouse models of amyloidosis. Here, we tested the implication of dopaminergic transmission in vivo in the Tg2576 mouse model of Alzheimer's disease by monitoring epileptic activities via intracranial EEG before and after treatment with dopamine antagonists. Our results show that neither the D1-like dopamine receptor antagonist SCH23390 nor the D2-like dopamine receptor antagonist haloperidol reduces the frequency of epileptic activities. While requiring further investigation, our results indicate that on a systemic level, dopamine receptors are not significantly contributing to epilepsy observed in vivo in this mouse model of Alzheimer's disease.
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Affiliation(s)
- Anna B Szabo
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
- Centre de recherche Cerveau et Cognition (CerCo), CNRS, UMR 5549, Toulouse Mind and Brain Institute (TMBI), University of Toulouse, University Paul Sabatier (UPS), Toulouse, France
| | - Farès Sayegh
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Sèbastien Gauzin
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Camille Lejards
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Bruno Guiard
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Luc Valton
- Centre de recherche Cerveau et Cognition (CerCo), CNRS, UMR 5549, Toulouse Mind and Brain Institute (TMBI), University of Toulouse, University Paul Sabatier (UPS), Toulouse, France
- Department of Neurology, Hôpital Pierre Paul Riquet - Purpan, Toulouse University Hospital, University of Toulouse, Toulouse, France
| | - Laure Verret
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Claire Rampon
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Lionel Dahan
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
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26
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Davidson B, Vetkas A, Germann J, Tang-Wai D, Lozano AM. Deep brain stimulation for Alzheimer's disease - current status and next steps. Expert Rev Med Devices 2024; 21:285-292. [PMID: 38573133 DOI: 10.1080/17434440.2024.2337298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 03/26/2024] [Indexed: 04/05/2024]
Abstract
INTRODUCTION Alzheimer's disease (AD) requires novel therapeutic approaches due to limited efficacy of current treatments. AREAS COVERED This article explores AD as a manifestation of neurocircuit dysfunction and evaluates deep brain stimulation (DBS) as a potential intervention. Focusing on fornix-targeted stimulation (DBS-f), the article summarizes safety, feasibility, and outcomes observed in phase 1/2 trials, highlighting findings such as cognitive improvement, increased metabolism, and hippocampal growth. Topics for further study include optimization of electrode placement, and the role of stimulation-induced autobiographical-recall. Nucleus basalis of Meynert (DBS-NBM) DBS is also discussed and compared with DBS-f. Challenges with both DBS-f and DBS-NBM are identified, emphasizing the need for further research on optimal stimulation parameters. The article also reviews alternative DBS targets, including medial temporal lobe structures and the ventral capsule/ventral striatum. EXPERT OPINION Looking ahead, a phase-3 DBS-f trial, and the prospect of closed-loop stimulation using EEG-derived biomarkers or hippocampal theta activity are highlighted. Recent FDA-approved therapies and other neuromodulation techniques like temporal interference and low-intensity ultrasound are considered. The article concludes by underscoring the importance of imaging-based diagnosis and staging to allow for circuit-targeted therapies, given the heterogeneity of AD and varied stages of neurocircuit dysfunction.
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Affiliation(s)
- Benjamin Davidson
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada
| | - Artur Vetkas
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada
| | - Jürgen Germann
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada
- Krembil Research Institute, Toronto, ON, Canada
| | - David Tang-Wai
- Krembil Research Institute, Toronto, ON, Canada
- Department of Neurology, Toronto Western Hospital, University Health Network, Toronto, University of Toronto, ON, Canada
| | - Andres M Lozano
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada
- Krembil Research Institute, Toronto, ON, Canada
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27
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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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28
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Almeida VN. Somatostatin and the pathophysiology of Alzheimer's disease. Ageing Res Rev 2024; 96:102270. [PMID: 38484981 DOI: 10.1016/j.arr.2024.102270] [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: 07/18/2023] [Revised: 03/09/2024] [Accepted: 03/09/2024] [Indexed: 03/28/2024]
Abstract
Among the central features of Alzheimer's disease (AD) progression are altered levels of the neuropeptide somatostatin (SST), and the colocalisation of SST-positive interneurons (SST-INs) with amyloid-β plaques, leading to cell death. In this theoretical review, I propose a molecular model for the pathogenesis of AD based on SST-IN hypofunction and hyperactivity. Namely, hypofunctional and hyperactive SST-INs struggle to control hyperactivity in medial regions in early stages, leading to axonal Aβ production through excessive presynaptic GABAB inhibition, GABAB1a/APP complex downregulation and internalisation. Concomitantly, excessive SST-14 release accumulates near SST-INs in the form of amyloids, which bind to Aβ to form toxic mixed oligomers. This leads to differential SST-IN death through excitotoxicity, further disinhibition, SST deficits, and increased Aβ release, fibrillation and plaque formation. Aβ plaques, hyperactive networks and SST-IN distributions thereby tightly overlap in the brain. Conversely, chronic stimulation of postsynaptic SST2/4 on gulutamatergic neurons by hyperactive SST-INs promotes intense Mitogen-Activated Protein Kinase (MAPK) p38 activity, leading to somatodendritic p-tau staining and apoptosis/neurodegeneration - in agreement with a near complete overlap between p38 and neurofibrillary tangles. This model is suitable to explain some of the principal risk factors and markers of AD progression, including mitochondrial dysfunction, APOE4 genotype, sex-dependent vulnerability, overactive glial cells, dystrophic neurites, synaptic/spine losses, inter alia. Finally, the model can also shed light on qualitative aspects of AD neuropsychology, especially within the domains of spatial and declarative (episodic, semantic) memory, under an overlying pattern of contextual indiscrimination, ensemble instability, interference and generalisation.
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Affiliation(s)
- Victor N Almeida
- Institute of Psychiatry, Faculty of Medicine, University of São Paulo (USP), Brazil; Faculty of Languages, Federal University of Minas Gerais (UFMG), Brazil.
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29
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Yao J, Chen SRW. RyR2-dependent modulation of neuronal hyperactivity: A potential therapeutic target for treating Alzheimer's disease. J Physiol 2024; 602:1509-1518. [PMID: 36866974 DOI: 10.1113/jp283824] [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: 11/29/2022] [Accepted: 02/27/2023] [Indexed: 03/04/2023] Open
Abstract
Increasing evidence suggests that simply reducing β-amyloid (Aβ) plaques may not significantly affect the progression of Alzheimer's disease (AD). There is also increasing evidence indicating that AD progression is driven by a vicious cycle of soluble Aβ-induced neuronal hyperactivity. In support of this, it has recently been shown that genetically and pharmacologically limiting ryanodine receptor 2 (RyR2) open time prevents neuronal hyperactivity, memory impairment, dendritic spine loss and neuronal cell death in AD mouse models. By contrast, increased RyR2 open probability (Po) exacerbates the onset of familial AD-associated neuronal dysfunction and induces AD-like defects in the absence of AD-causing gene mutations. Thus, RyR2-dependent modulation of neuronal hyperactivity represents a promising new target for combating AD.
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Affiliation(s)
- Jinjing Yao
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - S R Wayne Chen
- Libin Cardiovascular Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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30
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Balez R, Stevens CH, Lenk K, Maksour S, Sidhu K, Sutherland G, Ooi L. Increased Neuronal Nitric Oxide Synthase in Alzheimer's Disease Mediates Spontaneous Calcium Signaling and Divergent Glutamatergic Calcium Responses. Antioxid Redox Signal 2024. [PMID: 38299492 DOI: 10.1089/ars.2023.0395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
Nitrosative stress is a feature of Alzheimer's disease (AD). Aims: We aimed to identify the cause underpinning increased nitric oxide (NO) in neurons and the impact of NO on neuronal function in AD. Results: We analyzed neuronal nitric oxide synthase (nNOS) protein levels in postmortem tissue and induced pluripotent stem cell (iPSC)-derived neurons from Alzheimer's patients and controls by immunohistochemistry and Western blots. Furthermore, we assessed the impact of modulating nNOS function or NO levels on neuronal glutamatergic signaling using calcium imaging. We show that nNOS protein levels are increased in early and severely affected brain regions of AD postmortem tissue, but not late and mildly affected regions, or cognitively normal individuals. The increased nNOS phenotype was also present in iPSC-derived neurons from late-onset Alzheimer's disease (LOAD) patients compared with controls, along with increased levels of nitrite, a stable marker of NO. Innovation: We observed a divergent functional impact of NO that included strengthening the calcium response in control neurons, while dysregulating calcium signaling and altering the amplitude and kinetics of the calcium responses to glutamate in the AD neurons. Pharmacological scavenging of NO or inhibition of nNOS prevented aberrant spontaneous calcium signaling in AD neurons. Conclusion: Together these data identify increases in nNOS protein in AD. Functional data suggest that NO modulation of glutamatergic calcium signaling is neuroprotective under nonpathogenic conditions, with increased nNOS and NO contributing to dysregulated spontaneous calcium signaling in AD neurons.
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Affiliation(s)
- Rachelle Balez
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - Claire H Stevens
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - Kerstin Lenk
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
- Institute of Neural Engineering, Graz University of Technology, Graz, Austria
- BioTechMed, Graz, Austria
| | - Simon Maksour
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
| | - Kuldip Sidhu
- Centre for Healthy Brain Ageing (CheBA), University of New South Wales, Sydney, Australia
| | - Greg Sutherland
- Charles Perkins Centre, University of Sydney, Glebe, Australia
| | - Lezanne Ooi
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, Australia
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Yook Y, Lee KY, Kim E, Lizarazo S, Yu X, Tsai NP. Hyperfunction of post-synaptic density protein 95 promotes seizure response in early-stage aβ pathology. EMBO Rep 2024; 25:1233-1255. [PMID: 38413732 PMCID: PMC10933348 DOI: 10.1038/s44319-024-00090-0] [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: 05/30/2023] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 02/29/2024] Open
Abstract
Accumulation of amyloid-beta (Aβ) can lead to the formation of aggregates that contribute to neurodegeneration in Alzheimer's disease (AD). Despite globally reduced neural activity during AD onset, recent studies have suggested that Aβ induces hyperexcitability and seizure-like activity during the early stages of the disease that ultimately exacerbate cognitive decline. However, the underlying mechanism is unknown. Here, we reveal an Aβ-induced elevation of postsynaptic density protein 95 (PSD-95) in cultured neurons in vitro and in an in vivo AD model using APP/PS1 mice at 8 weeks of age. Elevation of PSD-95 occurs as a result of reduced ubiquitination caused by Akt-dependent phosphorylation of E3 ubiquitin ligase murine-double-minute 2 (Mdm2). The elevation of PSD-95 is consistent with the facilitation of excitatory synapses and the surface expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors induced by Aβ. Inhibition of PSD-95 corrects these Aβ-induced synaptic defects and reduces seizure activity in APP/PS1 mice. Our results demonstrate a mechanism underlying elevated seizure activity during early-stage Aβ pathology and suggest that PSD-95 could be an early biomarker and novel therapeutic target for AD.
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Affiliation(s)
- Yeeun Yook
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Kwan Young Lee
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Eunyoung Kim
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Simon Lizarazo
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Xinzhu Yu
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Nien-Pei Tsai
- Department of Molecular and Integrative Physiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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32
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Maruoka H, Hattori T, Hase T, Takahashi K, Ohara M, Orimo S, Yokota T. Aberrant morphometric networks in Alzheimer's disease have hemispheric asymmetry and age dependence. Eur J Neurosci 2024; 59:1332-1347. [PMID: 38105486 DOI: 10.1111/ejn.16225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 11/24/2023] [Accepted: 11/27/2023] [Indexed: 12/19/2023]
Abstract
Alzheimer's disease (AD) is associated with abnormal accumulations of hyperphosphorylated tau and amyloid-β proteins, resulting in unique patterns of atrophy in the brain. We aimed to elucidate some characteristics of the AD's morphometric networks constructed by associating different morphometric features among brain areas and evaluating their relationship to Mini-Mental State Examination total score and age. Three-dimensional T1-weighted (3DT1) image data scanned by the same 1.5T magnetic resonance imaging (MRI) were obtained from 62 AD patients and 41 healthy controls (HCs) and were analysed by using FreeSurfer. The associations of the extracted six morphometric features between regions were estimated by correlation coefficients. The global and local graph theoretical measures for this network were evaluated. Associations between graph theoretical measures and age, sex and cognition were evaluated by multiple regression analysis in each group. Global measures of integration: global efficiency and mean information centrality were significantly higher in AD patients. Local measures of integration: node global efficiency and information centrality were significantly higher in the entorhinal cortex, fusiform gyrus and posterior cingulate cortex of AD patients but only in the left hemisphere. All global measures were correlated with age in AD patients but not in HCs. The information centrality was associated with age in AD's broad brain regions. Our results showed that altered morphometric networks due to AD are left-hemisphere dominant, suggesting that AD pathogenesis has a left-right asymmetry. Ageing has a unique impact on the morphometric networks in AD patients. The information centrality is a sensitive graph theoretical measure to detect this association.
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Affiliation(s)
- Hiroyuki Maruoka
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Science, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Neurology, Kanto Central Hospital, Tokyo, Japan
| | - Takaaki Hattori
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Science, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takeshi Hase
- Innovative Human Resource Development Division, Institute of Education, Tokyo Medical and Dental University, Tokyo, Japan
- Faculty of Pharmacy, Keio University, Tokyo, Japan
- Research, The Systems Biology Institute, Tokyo, Japan
- Research, SBX BioSciences, Vancouver, British Columbia, Canada
| | - Kunihiko Takahashi
- Department of Biostatistics, M&D Data Science Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masahiro Ohara
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Science, Tokyo Medical and Dental University, Tokyo, Japan
| | - Satoshi Orimo
- Department of Neurology, Kanto Central Hospital, Tokyo, Japan
| | - Takanori Yokota
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Science, Tokyo Medical and Dental University, Tokyo, Japan
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Tzavellas NP, Tsamis KI, Katsenos AP, Davri AS, Simos YV, Nikas IP, Bellos S, Lekkas P, Kanellos FS, Konitsiotis S, Labrakakis C, Vezyraki P, Peschos D. Firing Alterations of Neurons in Alzheimer's Disease: Are They Merely a Consequence of Pathogenesis or a Pivotal Component of Disease Progression? Cells 2024; 13:434. [PMID: 38474398 DOI: 10.3390/cells13050434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/14/2024] Open
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder, yet its underlying causes remain elusive. The conventional perspective on disease pathogenesis attributes alterations in neuronal excitability to molecular changes resulting in synaptic dysfunction. Early hyperexcitability is succeeded by a progressive cessation of electrical activity in neurons, with amyloid beta (Aβ) oligomers and tau protein hyperphosphorylation identified as the initial events leading to hyperactivity. In addition to these key proteins, voltage-gated sodium and potassium channels play a decisive role in the altered electrical properties of neurons in AD. Impaired synaptic function and reduced neuronal plasticity contribute to a vicious cycle, resulting in a reduction in the number of synapses and synaptic proteins, impacting their transportation inside the neuron. An understanding of these neurophysiological alterations, combined with abnormalities in the morphology of brain cells, emerges as a crucial avenue for new treatment investigations. This review aims to delve into the detailed exploration of electrical neuronal alterations observed in different AD models affecting single neurons and neuronal networks.
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Affiliation(s)
- Nikolaos P Tzavellas
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Konstantinos I Tsamis
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
- Department of Neurology, Faculty of Medicine, School of Health Sciences, University Hospital of Ioannina, 455 00 Ioannina, Greece
| | - Andreas P Katsenos
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Athena S Davri
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Yannis V Simos
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Ilias P Nikas
- Medical School, University of Cyprus, 2029 Nicosia, Cyprus
| | - Stefanos Bellos
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Panagiotis Lekkas
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Foivos S Kanellos
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Spyridon Konitsiotis
- Department of Neurology, Faculty of Medicine, School of Health Sciences, University Hospital of Ioannina, 455 00 Ioannina, Greece
| | - Charalampos Labrakakis
- Department of Biological Applications and Technology, University of Ioannina, 451 10 Ioannina, Greece
| | - Patra Vezyraki
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
| | - Dimitrios Peschos
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 451 10 Ioannina, Greece
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Mao R, Hu M, Liu X, Ye L, Xu B, Sun M, Xu S, Shao W, Tan Y, Xu Y, Bai F, Shu S. Impairments of GABAergic transmission in hippocampus mediate increased susceptibility of epilepsy in the early stage of Alzheimer's disease. Cell Commun Signal 2024; 22:147. [PMID: 38388921 PMCID: PMC10885444 DOI: 10.1186/s12964-024-01528-7] [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: 12/18/2023] [Accepted: 02/13/2024] [Indexed: 02/24/2024] Open
Abstract
BACKGROUND Patients with Alzheimer's disease (AD) are often co-morbid with unprovoked seizures, making clinical diagnosis and management difficult. Although it has an important role in both AD and epilepsy, abnormal γ-aminobutyric acid (GABA)ergic transmission is recognized only as a compensative change for glutamatergic damage. Neuregulin 1 (NRG1)-ErbB4 signaling can promote GABA release and suppress epileptogenesis, but its effects on cognition in AD are still controversial. METHODS Four-month-old APPswe/PS1dE9 mice (APP mice) were used as animal models in the early stage of AD in this study. Acute/chronic chemical-kindling epilepsy models were established with pentylenetetrazol. Electroencephalogram and Racine scores were performed to assess seizures. Behavioral tests were used to assess cognition and emotion. Electrophysiology, western blot and immunofluorescence were performed to detect the alterations in synapses, GABAergic system components and NRG1-ErbB4 signaling. Furthermore, NRG1 was administrated intracerebroventricularly into APP mice and then its antiepileptic and cognitive effects were evaluated. RESULTS APP mice had increased susceptibility to epilepsy and resulting hippocampal synaptic damage and cognitive impairment. Electrophysiological analysis revealed decreased GABAergic transmission in the hippocampus. This abnormal GABAergic transmission involved a reduction in the number of parvalbumin interneurons (PV+ Ins) and decreased levels of GABA synthesis and transport. We also found impaired NRG1-ErbB4 signaling which mediated by PV+ Ins loss. And NRG1 administration could effectively reduce seizures and improve cognition in four-month-old APP mice. CONCLUSION Our results indicated that abnormal GABAergic transmission mediated hippocampal hyperexcitability, further excitation/inhibition imbalance, and promoted epileptogenesis in the early stage of AD. Appropriate NRG1 administration could down-regulate seizure susceptibility and rescue cognitive function. Our study provided a potential direction for intervening in the co-morbidity of AD and epilepsy.
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Affiliation(s)
- Rui Mao
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Mengsha Hu
- Department of Neurology, Nanjing Drum Tower Hospital Clinical College of Nanjing University of Chinese Medicine, Nanjing, China
| | - Xuan Liu
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Lei Ye
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Bingsong Xu
- Department of Neurology, Nanjing Drum Tower Hospital Clinical College of Nanjing University of Chinese Medicine, Nanjing, China
| | - Min Sun
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Siyi Xu
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Wenxuan Shao
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Yi Tan
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Yun Xu
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China.
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China.
- Jiangsu Provincial Key Discipline of Neurology, Nanjing, China.
- Nanjing Neurology Medical Center, Nanjing, China.
| | - Feng Bai
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China.
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China.
- Jiangsu Provincial Key Discipline of Neurology, Nanjing, China.
- Nanjing Neurology Medical Center, Nanjing, China.
| | - Shu Shu
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
- Department of Neurology, Nanjing Drum Tower Hospital, State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases, Nanjing University, Nanjing, China.
- Jiangsu Key Laboratory for Molecular Medicine, Medical School of Nanjing University, Nanjing, China.
- Jiangsu Provincial Key Discipline of Neurology, Nanjing, China.
- Nanjing Neurology Medical Center, Nanjing, China.
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Malik N, Miah MU, Galgani A, McAleese K, Walker L, LeBeau FE, Attems J, Outeiro TF, Thomas A, Koss DJ. Regional AT-8 reactive tau species correlate with intracellular Aβ levels in cases of low AD neuropathologic change. Acta Neuropathol 2024; 147:40. [PMID: 38353753 PMCID: PMC10866780 DOI: 10.1007/s00401-024-02691-4] [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: 11/09/2023] [Revised: 12/21/2023] [Accepted: 01/19/2024] [Indexed: 02/16/2024]
Abstract
The amyloid cascade hypothesis states that Aβ aggregates induce pathological changes in tau, leading to neurofibrillary tangles (NFTs) and cell death. A caveat with this hypothesis is the spatio-temporal divide between plaques and NFTs. This has been addressed by the inclusion of soluble Aβ and tau species in the revised amyloid cascade hypothesis. Nevertheless, despite the potential for non-plaque Aβ to contribute to tau pathology, few studies have examined relative correlative strengths between total Aβ, plaque Aβ and intracellular Aβ with tau pathology within a single tissue cohort. Employing frozen and fixed frontal cortex grey and white matter tissue from non-AD controls (Con; n = 39) and Alzheimer's disease (AD) cases (n = 21), biochemical and immunohistochemical (IHC) measures of Aβ and AT-8 phosphorylated tau were assessed. Biochemical native-state dot blots from crude tissue lysates demonstrated robust correlations between total Aβ and AT-8 tau, when considered as a combined cohort (Con and AD) and when as Con and AD cases, separately. In contrast, no associations between Aβ plaques and AT-8 were reported when using IHC measurements in either Con or AD cases. However, when intracellular Aβ was measured via the Aβ specific antibody MOAB-2, a correlative relationship with AT-8 tau was reported in non-AD controls but not in AD cases. Collectively the data suggests that accumulating intracellular Aβ may influence AT-8 pathology, early in AD-related neuropathological change. Despite the lower levels of phospho-tau and Aβ in controls, the robust correlative relationships observed suggest a physiological association of Aβ production and tau phosphorylation, which may be modified during disease. This study is supportive of a revised amyloid cascade hypothesis and demonstrates regional associative relationships between tau pathology and intracellular Aβ, but not extracellular Aβ plaques.
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Affiliation(s)
- Nauman Malik
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Mohi-Uddin Miah
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Alessandro Galgani
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Kirsty McAleese
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Lauren Walker
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Fiona E LeBeau
- Biosciences, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Johannes Attems
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Tiago F Outeiro
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Göttingen, Germany
- Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Alan Thomas
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - David J Koss
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK.
- Division of Cellular and Systems Medicine, School of Medicine, University of Dundee, Dundee, Scotland, UK.
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Escalada P, Ezkurdia A, Ramírez MJ, Solas M. Essential Role of Astrocytes in Learning and Memory. Int J Mol Sci 2024; 25:1899. [PMID: 38339177 PMCID: PMC10856373 DOI: 10.3390/ijms25031899] [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: 01/17/2024] [Revised: 01/31/2024] [Accepted: 02/02/2024] [Indexed: 02/12/2024] Open
Abstract
One of the most biologically relevant functions of astrocytes within the CNS is the regulation of synaptic transmission, i.e., the physiological basis for information transmission between neurons. Changes in the strength of synaptic connections are indeed thought to be the cellular basis of learning and memory. Importantly, astrocytes have been demonstrated to tightly regulate these processes via the release of several gliotransmitters linked to astrocytic calcium activity as well as astrocyte-neuron metabolic coupling. Therefore, astrocytes seem to be integrators of and actors upon learning- and memory-relevant information. In this review, we focus on the role of astrocytes in learning and memory processes. We delineate the recognized inputs and outputs of astrocytes and explore the influence of manipulating astrocytes on behaviour across diverse learning paradigms. We conclude that astrocytes influence learning and memory in various manners. Appropriate astrocytic Ca2+ dynamics are being increasingly identified as central contributors to memory formation and retrieval. In addition, astrocytes regulate brain rhythms essential for cognition, and astrocyte-neuron metabolic cooperation is required for memory consolidation.
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Affiliation(s)
- Paula Escalada
- Department of Pharmaceutical Sciences, University of Navarra, 31008 Pamplona, Spain; (P.E.); (A.E.); (M.J.R.)
| | - Amaia Ezkurdia
- Department of Pharmaceutical Sciences, University of Navarra, 31008 Pamplona, Spain; (P.E.); (A.E.); (M.J.R.)
- IdiSNA, Navarra Institute for Health Research, 31008 Pamplona, Spain
| | - María Javier Ramírez
- Department of Pharmaceutical Sciences, University of Navarra, 31008 Pamplona, Spain; (P.E.); (A.E.); (M.J.R.)
- IdiSNA, Navarra Institute for Health Research, 31008 Pamplona, Spain
| | - Maite Solas
- Department of Pharmaceutical Sciences, University of Navarra, 31008 Pamplona, Spain; (P.E.); (A.E.); (M.J.R.)
- IdiSNA, Navarra Institute for Health Research, 31008 Pamplona, Spain
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Tang T, Li X, Yu E, Li M, Pan X. Identification of common core ion channel genes in epilepsy and Alzheimer's disease. Ir J Med Sci 2024; 193:417-424. [PMID: 37477849 DOI: 10.1007/s11845-023-03447-x] [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: 01/30/2023] [Accepted: 06/23/2023] [Indexed: 07/22/2023]
Abstract
BACKGROUND Although available literature indicates that the incidence of dementia in the epilepsy population and the risk of seizures in the Alzheimer's disease (AD) population are high, the specific genetic risk factors and the interaction mechanism are unclear, rendering rational genetic interpretation rather challenging. AIMS Our work aims to identify the common core ion channel genes in epilepsy and AD. METHODS In this study, we first integrated gene expression omnibus datasets (GSE48350 and GSE6834) on AD and epilepsy to identify differentially expressed genes (DEGs), performing Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs. The related protein-protein interaction (PPI) network was constructed for DEGs, and the hub gene was evaluated. RESULTS A total of 2800 and 35 genes were identified in GSE48350 and GSE6834, and 12 DEGs were significantly differentially expressed between the datasets. KEGG pathway analysis showed that DEGs were primarily enriched in glutamatergic synapse and dopaminergic synapse pathways. SCN2A, GRIA1, and KCNJ9 were the hub genes with high connectivity. CONCLUSIONS The findings suggest that the three genes, SCN2A, GRIA1, and KCNJ9, may serve as potential targets for treating AD comorbid with epilepsy.
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Affiliation(s)
- Ting Tang
- Department of Neurology, The Second Affiliated Hospital of Fujian Medical University, 34 Zhongshan North Road, Quanzhou, Fujian, 362000, People's Republic of China
| | - Xiang Li
- Department of Neurology, Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, Fujian, 350001, People's Republic of China
| | - Erhan Yu
- Department of Neurology, Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, Fujian, 350001, People's Republic of China
| | - Man Li
- Department of Neurology, Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, Fujian, 350001, People's Republic of China
| | - Xiaodong Pan
- Department of Neurology, Center for Cognitive Neurology, Fujian Institute of Geriatrics, Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, Fujian, 350001, People's Republic of China.
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Zhu Y, Huang H, Chen Z, Tao Y, Liao LY, Gao SH, Wang YJ, Gao CY. Intermittent Theta Burst Stimulation Attenuates Cognitive Deficits and Alzheimer's Disease-Type Pathologies via ISCA1-Mediated Mitochondrial Modulation in APP/PS1 Mice. Neurosci Bull 2024; 40:182-200. [PMID: 37578635 PMCID: PMC10838862 DOI: 10.1007/s12264-023-01098-7] [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: 01/19/2023] [Accepted: 04/28/2023] [Indexed: 08/15/2023] Open
Abstract
Intermittent theta burst stimulation (iTBS), a time-saving and cost-effective repetitive transcranial magnetic stimulation regime, has been shown to improve cognition in patients with Alzheimer's disease (AD). However, the specific mechanism underlying iTBS-induced cognitive enhancement remains unknown. Previous studies suggested that mitochondrial functions are modulated by magnetic stimulation. Here, we showed that iTBS upregulates the expression of iron-sulfur cluster assembly 1 (ISCA1, an essential regulatory factor for mitochondrial respiration) in the brain of APP/PS1 mice. In vivo and in vitro studies revealed that iTBS modulates mitochondrial iron-sulfur cluster assembly to facilitate mitochondrial respiration and function, which is required for ISCA1. Moreover, iTBS rescues cognitive decline and attenuates AD-type pathologies in APP/PS1 mice. The present study uncovers a novel mechanism by which iTBS modulates mitochondrial respiration and function via ISCA1-mediated iron-sulfur cluster assembly to alleviate cognitive impairments and pathologies in AD. We provide the mechanistic target of iTBS that warrants its therapeutic potential for AD patients.
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Affiliation(s)
- Yang Zhu
- Department of Rehabilitation Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Hao Huang
- Department of Rehabilitation Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Zhi Chen
- Department of Special Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Yong Tao
- Department of Rehabilitation Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Ling-Yi Liao
- Department of Rehabilitation Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Shi-Hao Gao
- Department of Rehabilitation Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China.
| | - Yan-Jiang Wang
- Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Army Medical University, Chongqing, 400042, China.
| | - Chang-Yue Gao
- Department of Rehabilitation Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, China.
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da Silva SP, de Castro CCM, Rabelo LN, Engelberth RC, Fernández-Calvo B, Fiuza FP. Neuropathological and sociodemographic factors associated with the cortical amyloid load in aging and Alzheimer's disease. GeroScience 2024; 46:621-643. [PMID: 37870702 PMCID: PMC10828279 DOI: 10.1007/s11357-023-00982-4] [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: 06/06/2023] [Accepted: 10/10/2023] [Indexed: 10/24/2023] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia and is characterized by a progressive decline in cognitive abilities. A pathological hallmark of AD is a region-specific accumulation of the amyloid-beta protein (Aβ). Here, we explored the association between regional Aβ deposition, sociodemographic, and local biochemical factors. We quantified the Aβ burden in postmortem cortical samples from parietal (PCx) and temporal (TCx) regions of 27 cognitively unimpaired (CU) and 15 AD donors, aged 78-100 + years. Histological images of Aβ immunohistochemistry and local concentrations of pathological and inflammatory proteins were obtained at the "Aging, Dementia and TBI Study" open database. We used the area fraction fractionator stereological methodology to quantify the Aβ burden in the gray and white matter within each cortical region. We found higher Aβ burdens in the TCx of AD octogenarians compared to CU ones. We also found higher Aβ loads in the PCx of AD nonagenarians than in AD octogenarians. Moreover, AD women exhibited increased Aβ deposition compared to CU women. Interestingly, we observed a negative correlation between education years and Aβ burden in the white matter of both cortices in CU samples. In AD brains, the Aβ40, Aβ42, and pTau181 isoforms of Aβ and Tau proteins were positively correlated with the Aβ burden. Additionally, in the TCx of AD donors, the proinflammatory cytokine TNFα showed a positive correlation with the Aβ load. These novel findings contribute to understanding the interplay between sociodemographic characteristics, local inflammatory signaling, and the development of AD-related pathology in the cerebral cortex.
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Affiliation(s)
- Sayonara P da Silva
- Graduate Program in Neuroengineering, Edmond and Lily Safra International Institute of Neuroscience, Santos Dumont Institute, Macaíba, RN, 59280-000, Brazil
| | - Carla C M de Castro
- Graduate Program in Neuroengineering, Edmond and Lily Safra International Institute of Neuroscience, Santos Dumont Institute, Macaíba, RN, 59280-000, Brazil
| | - Lívia N Rabelo
- Graduate Program in Neuroengineering, Edmond and Lily Safra International Institute of Neuroscience, Santos Dumont Institute, Macaíba, RN, 59280-000, Brazil
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Biosciences Center, Federal University of Rio Grande Do Norte, Natal, Brazil
| | - Rovena C Engelberth
- Laboratory of Neurochemical Studies, Department of Physiology and Behavior, Biosciences Center, Federal University of Rio Grande Do Norte, Natal, Brazil
| | - Bernardino Fernández-Calvo
- Department of Psychology, University of Córdoba, Córdoba, Spain
- Maimonides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain
- Reina Sofia University Hospital, Córdoba, Spain
- Department of Psychology, Federal University of Paraíba, João Pessoa, Brazil
| | - Felipe P Fiuza
- Graduate Program in Neuroengineering, Edmond and Lily Safra International Institute of Neuroscience, Santos Dumont Institute, Macaíba, RN, 59280-000, Brazil.
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40
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Nous A, Seynaeve L, Feys O, Wens V, De Tiège X, Van Mierlo P, Baroumand AG, Nieboer K, Allemeersch GJ, Mangelschots S, Michiels V, van der Zee J, Van Broeckhoven C, Ribbens A, Houbrechts R, De Witte S, Wittens MMJ, Bjerke M, Vanlersberghe C, Ceyssens S, Nagels G, Smolders I, Engelborghs S. Subclinical epileptiform activity in the Alzheimer continuum: association with disease, cognition and detection method. Alzheimers Res Ther 2024; 16:19. [PMID: 38263073 PMCID: PMC10804650 DOI: 10.1186/s13195-023-01373-9] [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: 09/13/2023] [Accepted: 12/17/2023] [Indexed: 01/25/2024]
Abstract
BACKGROUND Epileptic seizures are an established comorbidity of Alzheimer's disease (AD). Subclinical epileptiform activity (SEA) as detected by 24-h electroencephalography (EEG) or magneto-encephalography (MEG) has been reported in temporal regions of clinically diagnosed AD patients. Although epileptic activity in AD probably arises in the mesial temporal lobe, electrical activity within this region might not propagate to EEG scalp electrodes and could remain undetected by standard EEG. However, SEA might lead to faster cognitive decline in AD. AIMS 1. To estimate the prevalence of SEA and interictal epileptic discharges (IEDs) in a well-defined cohort of participants belonging to the AD continuum, including preclinical AD subjects, as compared with cognitively healthy controls. 2. To evaluate whether long-term-EEG (LTM-EEG), high-density-EEG (hd-EEG) or MEG is superior to detect SEA in AD. 3. To characterise AD patients with SEA based on clinical, neuropsychological and neuroimaging parameters. METHODS Subjects (n = 49) belonging to the AD continuum were diagnosed according to the 2011 NIA-AA research criteria, with a high likelihood of underlying AD pathophysiology. Healthy volunteers (n = 24) scored normal on neuropsychological testing and were amyloid negative. None of the participants experienced a seizure before. Subjects underwent LTM-EEG and/or 50-min MEG and/or 50-min hd-EEG to detect IEDs. RESULTS We found an increased prevalence of SEA in AD subjects (31%) as compared to controls (8%) (p = 0.041; Fisher's exact test), with increasing prevalence over the disease course (50% in dementia, 27% in MCI and 25% in preclinical AD). Although MEG (25%) did not withhold a higher prevalence of SEA in AD as compared to LTM-EEG (19%) and hd-EEG (19%), MEG was significantly superior to detect spikes per 50 min (p = 0.002; Kruskall-Wallis test). AD patients with SEA scored worse on the RBANS visuospatial and attention subset (p = 0.009 and p = 0.05, respectively; Mann-Whitney U test) and had higher left frontal, (left) temporal and (left and right) entorhinal cortex volumes than those without. CONCLUSION We confirmed that SEA is increased in the AD continuum as compared to controls, with increasing prevalence with AD disease stage. In AD patients, SEA is associated with more severe visuospatial and attention deficits and with increased left frontal, (left) temporal and entorhinal cortex volumes. TRIAL REGISTRATION Clinicaltrials.gov, NCT04131491. 12/02/2020.
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Affiliation(s)
- Amber Nous
- Department of Neurology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium
- Laboratory of Pharmaceutical Chemistry, Drug Analysis and Drug Information (FASC), Research Group Experimental Pharmacology (EFAR), Center for Neurosciences, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Laura Seynaeve
- Department of Neurology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Odile Feys
- Department of Neurology, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (HUB), Hôpital Erasme, Brussels, Belgium
- Laboratoire de Neuroimagerie Et Neuroanatomie Translationnelles (LN2T), Université Libre de Bruxelles (ULB), ULB Neuroscience Institute (UNI), Brussels, Belgium
| | - Vincent Wens
- Laboratoire de Neuroimagerie Et Neuroanatomie Translationnelles (LN2T), Université Libre de Bruxelles (ULB), ULB Neuroscience Institute (UNI), Brussels, Belgium
- Department of Translational Neuroimaging, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (HUB), Hôpital Erasme, Brussels, Belgium
| | - Xavier De Tiège
- Laboratoire de Neuroimagerie Et Neuroanatomie Translationnelles (LN2T), Université Libre de Bruxelles (ULB), ULB Neuroscience Institute (UNI), Brussels, Belgium
- Department of Translational Neuroimaging, Université Libre de Bruxelles (ULB), Hôpital Universitaire de Bruxelles (HUB), Hôpital Erasme, Brussels, Belgium
| | | | | | - Koenraad Nieboer
- Department of Radiology, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Gert-Jan Allemeersch
- Department of Radiology, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Shana Mangelschots
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium
| | - Veronique Michiels
- Department of Neurology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Julie van der Zee
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium
- Neurodegenerative Brain Diseases, VIB Center for Molecular Neurology, Antwerp, Belgium
| | - Christine Van Broeckhoven
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium
- Neurodegenerative Brain Diseases, VIB Center for Molecular Neurology, Antwerp, Belgium
| | | | | | - Sara De Witte
- Department of Neurology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Mandy Melissa Jane Wittens
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium
| | - Maria Bjerke
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium
- Department of Clinical Biology, Laboratory of Clinical Neurochemistry, Universitair Ziekenhuis Brussel, Brussels, Belgium
| | - Caroline Vanlersberghe
- Department of Anaesthesiology and Perioperative Medicine, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
| | - Sarah Ceyssens
- Department of Nuclear Medicine, Universitair Ziekenhuis Antwerpen, University of Antwerp, Antwerpen, Belgium
| | - Guy Nagels
- Department of Neurology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium
- Artificial Intelligence Supported Modelling in Clinical Sciences (AIMS) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Ilse Smolders
- Laboratory of Pharmaceutical Chemistry, Drug Analysis and Drug Information (FASC), Research Group Experimental Pharmacology (EFAR), Center for Neurosciences, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Sebastiaan Engelborghs
- Department of Neurology, Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium.
- Neuroprotection and Neuromodulation (NEUR) Research Group, Center for Neurosciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium.
- Department of Biomedical Sciences, Universiteit Antwerpen, Antwerp, Belgium.
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Zhang L, Qu J, Ma H, Chen T, Liu T, Zhu D. Exploring Alzheimer's disease: a comprehensive brain connectome-based survey. PSYCHORADIOLOGY 2024; 4:kkad033. [PMID: 38333558 PMCID: PMC10848159 DOI: 10.1093/psyrad/kkad033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/21/2023] [Accepted: 01/03/2024] [Indexed: 02/10/2024]
Abstract
Dementia is an escalating global health challenge, with Alzheimer's disease (AD) at its forefront. Substantial evidence highlights the accumulation of AD-related pathological proteins in specific brain regions and their subsequent dissemination throughout the broader area along the brain network, leading to disruptions in both individual brain regions and their interconnections. Although a comprehensive understanding of the neurodegeneration-brain network link is lacking, it is undeniable that brain networks play a pivotal role in the development and progression of AD. To thoroughly elucidate the intricate network of elements and connections constituting the human brain, the concept of the brain connectome was introduced. Research based on the connectome holds immense potential for revealing the mechanisms underlying disease development, and it has become a prominent topic that has attracted the attention of numerous researchers. In this review, we aim to systematically summarize studies on brain networks within the context of AD, critically analyze the strengths and weaknesses of existing methodologies, and offer novel perspectives and insights, intending to serve as inspiration for future research.
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Affiliation(s)
- Lu Zhang
- Department of Computer Science and Engineering, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Junqi Qu
- Department of Computer Science and Engineering, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Haotian Ma
- Department of Computer Science and Engineering, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Tong Chen
- Department of Computer Science and Engineering, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Tianming Liu
- Department of Computer Science, The University of Georgia, Athens, GA 30602, USA
| | - Dajiang Zhu
- Department of Computer Science and Engineering, The University of Texas at Arlington, Arlington, TX 76019, USA
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42
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Tagliatti E, Desiato G, Mancinelli S, Bizzotto M, Gagliani MC, Faggiani E, Hernández-Soto R, Cugurra A, Poliseno P, Miotto M, Argüello RJ, Filipello F, Cortese K, Morini R, Lodato S, Matteoli M. Trem2 expression in microglia is required to maintain normal neuronal bioenergetics during development. Immunity 2024; 57:86-105.e9. [PMID: 38159572 PMCID: PMC10783804 DOI: 10.1016/j.immuni.2023.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 07/17/2023] [Accepted: 12/05/2023] [Indexed: 01/03/2024]
Abstract
Triggering receptor expressed on myeloid cells 2 (Trem2) is a myeloid cell-specific gene expressed in brain microglia, with variants that are associated with neurodegenerative diseases, including Alzheimer's disease. Trem2 is essential for microglia-mediated synaptic refinement, but whether Trem2 contributes to shaping neuronal development remains unclear. Here, we demonstrate that Trem2 plays a key role in controlling the bioenergetic profile of pyramidal neurons during development. In the absence of Trem2, developing neurons in the hippocampal cornus ammonis (CA)1 but not in CA3 subfield displayed compromised energetic metabolism, accompanied by reduced mitochondrial mass and abnormal organelle ultrastructure. This was paralleled by the transcriptional rearrangement of hippocampal pyramidal neurons at birth, with a pervasive alteration of metabolic, oxidative phosphorylation, and mitochondrial gene signatures, accompanied by a delay in the maturation of CA1 neurons. Our results unveil a role of Trem2 in controlling neuronal development by regulating the metabolic fitness of neurons in a region-specific manner.
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Affiliation(s)
- Erica Tagliatti
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy; Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Genni Desiato
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy
| | - Sara Mancinelli
- Humanitas University, Department of Biomedical Sciences, Via Levi Montalicini 4, Pieve Emanuele 20072 Milan, Italy
| | - Matteo Bizzotto
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy; Humanitas University, Department of Biomedical Sciences, Via Levi Montalicini 4, Pieve Emanuele 20072 Milan, Italy
| | - Maria C Gagliani
- Cellular Electron Microscopy Laboratory, Department of Experimental Medicine (DIMES), Human Anatomy, Università di Genova, Via Antonio de Toni 14, 16132 Genova, Italy
| | - Elisa Faggiani
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy
| | | | - Andrea Cugurra
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy
| | - Paola Poliseno
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy
| | - Matteo Miotto
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy
| | - Rafael J Argüello
- Aix Marseille Univ, CNRS, INSERM, CIML, Centre d'Immunologie de Marseille-Luminy, Marseille, France
| | - Fabia Filipello
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy; Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA
| | - Katia Cortese
- Cellular Electron Microscopy Laboratory, Department of Experimental Medicine (DIMES), Human Anatomy, Università di Genova, Via Antonio de Toni 14, 16132 Genova, Italy
| | - Raffaella Morini
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy
| | - Simona Lodato
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy; Humanitas University, Department of Biomedical Sciences, Via Levi Montalicini 4, Pieve Emanuele 20072 Milan, Italy
| | - Michela Matteoli
- IRCCS Humanitas Research Hospital, via Manzoni 56, Rozzano, 20089 Milan, Italy; Institute of Neuroscience - National Research Council, 20139 Milan, Italy.
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Viana da Silva S, Haberl MG, Gaur K, Patel R, Narayan G, Ledakis M, Fu ML, de Castro Vieira M, Koo EH, Leutgeb JK, Leutgeb S. Localized APP expression results in progressive network dysfunction by disorganizing spike timing. Neuron 2024; 112:124-140.e6. [PMID: 37909036 PMCID: PMC10877582 DOI: 10.1016/j.neuron.2023.10.001] [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: 12/26/2022] [Revised: 06/16/2023] [Accepted: 10/02/2023] [Indexed: 11/02/2023]
Abstract
Progressive cognitive decline in Alzheimer's disease could either be caused by a spreading molecular pathology or by an initially focal pathology that causes aberrant neuronal activity in a larger network. To distinguish between these possibilities, we generated a mouse model with expression of mutant human amyloid precursor protein (APP) in only hippocampal CA3 cells. We found that performance in a hippocampus-dependent memory task was impaired in young adult and aged mutant mice. In both age groups, we then recorded from the CA1 region, which receives inputs from APP-expressing CA3 cells. We observed that theta oscillation frequency in CA1 was reduced along with disrupted relative timing of principal cells. Highly localized pathology limited to the presynaptic CA3 cells is thus sufficient to cause aberrant firing patterns in postsynaptic neuronal networks, which indicates that disease progression is not only from spreading pathology but also mediated by progressively advancing physiological dysfunction.
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Affiliation(s)
- Silvia Viana da Silva
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA; NeuroCure Excellence Cluster and German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | - Matthias G Haberl
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Neuroscience Research Center, Charitéplatz 1, 10117 Berlin, Germany
| | - Kshitij Gaur
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Rina Patel
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Gautam Narayan
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Max Ledakis
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Maylin L Fu
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Miguel de Castro Vieira
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Neuroscience Research Center, Charitéplatz 1, 10117 Berlin, Germany
| | - Edward H Koo
- Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Jill K Leutgeb
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA.
| | - Stefan Leutgeb
- Neurobiology Department, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA; Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA.
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Franzmeier N, Dehsarvi A, Steward A, Biel D, Dewenter A, Roemer SN, Wagner F, Groß M, Brendel M, Moscoso A, Arunachalam P, Blennow K, Zetterberg H, Ewers M, Schöll M. Elevated CSF GAP-43 is associated with accelerated tau accumulation and spread in Alzheimer's disease. Nat Commun 2024; 15:202. [PMID: 38172114 PMCID: PMC10764818 DOI: 10.1038/s41467-023-44374-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Abstract
In Alzheimer's disease, amyloid-beta (Aβ) triggers the trans-synaptic spread of tau pathology, and aberrant synaptic activity has been shown to promote tau spreading. Aβ induces aberrant synaptic activity, manifesting in increases in the presynaptic growth-associated protein 43 (GAP-43), which is closely involved in synaptic activity and plasticity. We therefore tested whether Aβ-related GAP-43 increases, as a marker of synaptic changes, drive tau spreading in 93 patients across the aging and Alzheimer's spectrum with available CSF GAP-43, amyloid-PET and longitudinal tau-PET assessments. We found that (1) higher GAP-43 was associated with faster Aβ-related tau accumulation, specifically in brain regions connected closest to subject-specific tau epicenters and (2) that higher GAP-43 strengthened the association between Aβ and connectivity-associated tau spread. This suggests that GAP-43-related synaptic changes are linked to faster Aβ-related tau spread across connected regions and that synapses could be key targets for preventing tau spreading in Alzheimer's disease.
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Affiliation(s)
- Nicolai Franzmeier
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany.
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
- University of Gothenburg, The Sahlgrenska Academy, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Mölndal and Gothenburg, Sweden.
| | - Amir Dehsarvi
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Anna Steward
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Davina Biel
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Anna Dewenter
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Sebastian Niclas Roemer
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Fabian Wagner
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
| | - Mattes Groß
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany
| | - Matthias Brendel
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
- Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany
| | - Alexis Moscoso
- University of Gothenburg, The Sahlgrenska Academy, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Mölndal and Gothenburg, Sweden
| | - Prithvi Arunachalam
- University of Gothenburg, The Sahlgrenska Academy, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Mölndal and Gothenburg, Sweden
| | - Kaj Blennow
- University of Gothenburg, The Sahlgrenska Academy, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Mölndal and Gothenburg, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- University of Gothenburg, The Sahlgrenska Academy, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Mölndal and Gothenburg, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Michael Ewers
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Michael Schöll
- University of Gothenburg, The Sahlgrenska Academy, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Mölndal and Gothenburg, Sweden
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
- Dementia Research Centre, Queen Square Institute of Neurology, University College London, London, UK
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Scheinman SB, Tseng KY, Alford S, Tai LM. Higher Neuronal Facilitation and Potentiation with APOE4 Suppressed by Angiotensin II. Mol Neurobiol 2024; 61:120-131. [PMID: 37589833 PMCID: PMC10843153 DOI: 10.1007/s12035-023-03556-9] [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: 05/22/2023] [Accepted: 08/01/2023] [Indexed: 08/18/2023]
Abstract
Progressive hippocampal degeneration is a key component of Alzheimer's disease (AD) progression. Therefore, identifying how hippocampal neuronal function is modulated early in AD is an important approach to eventually prevent degeneration. AD-risk factors and signaling molecules likely modulate neuronal function, including APOE genotype and angiotensin II. Compared to APOE3, APOE4 increases AD risk up to 12-fold, and high levels of angiotensin II are hypothesized to disrupt neuronal function in AD. However, the extent that APOE and angiotensin II modulates the hippocampal neuronal phenotype in AD-relevant models is unknown. To address this issue, we used electrophysiological techniques to assess the impact of APOE genotype and angiotensin II on basal synaptic transmission, presynaptic, and post-synaptic activity in mice that express human APOE3 (E3FAD) or APOE4 (E4FAD) and overproduce Aβ. We found that compared to E3FAD mice, E4FAD mice have lower synaptic activity, but higher levels of paired-pulse facilitation (PPF) and long-term potentiation (LTP) in the Schaffer Collateral Commissural Pathway (SCCP) of the hippocampus. We also found that exogenous angiotensin II has a profound inhibitory effect on hippocampal LTP in both E3FAD and E4FAD mice. Collectively, our data suggests that APOE4 and Aβ are associated with a hippocampal phenotype comprised of lower basal activity and higher responses to high-frequency stimulation, the latter of which is suppressed by angiotensin II. These novel data suggest a potential mechanistic link between hippocampal activity, APOE4 genotype, and angiotensin II in AD.
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Affiliation(s)
- Sarah B Scheinman
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St. Rm 578 MC 512, Chicago, IL, 60612, USA
| | - Kuei Y Tseng
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St. Rm 578 MC 512, Chicago, IL, 60612, USA
| | - Simon Alford
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St. Rm 578 MC 512, Chicago, IL, 60612, USA
| | - Leon M Tai
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, 808 S. Wood St. Rm 578 MC 512, Chicago, IL, 60612, USA.
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Chen K, Gupta R, Martín‐Ávila A, Cui M, Xie Z, Yang G. Anesthesia-induced hippocampal-cortical hyperactivity and tau hyperphosphorylation impair remote memory retrieval in Alzheimer's disease. Alzheimers Dement 2024; 20:494-510. [PMID: 37695022 PMCID: PMC10843666 DOI: 10.1002/alz.13464] [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: 03/23/2023] [Revised: 07/25/2023] [Accepted: 08/16/2023] [Indexed: 09/12/2023]
Abstract
INTRODUCTION Anesthesia often exacerbates memory recall difficulties in individuals with Alzheimer's disease (AD), but the underlying mechanisms remain unclear. METHODS We used in vivo Ca2+ imaging, viral-based circuit tracing, and chemogenetic approaches to investigate anesthesia-induced remote memory impairment in mouse models of presymptomatic AD. RESULTS Our study identified pyramidal neuron hyperactivity in the anterior cingulate cortex (ACC) as a significant contributor to anesthesia-induced remote memory impairment. This ACC hyperactivation arises from the disinhibition of local inhibitory circuits and increased excitatory inputs from the hippocampal CA1 region. Inhibiting hyperactivity in the CA1-ACC circuit improved memory recall after anesthesia. Moreover, anesthesia led to increased tau phosphorylation in the hippocampus, and inhibiting this hyperphosphorylation prevented ACC hyperactivity and subsequent memory impairment. DISCUSSION Hippocampal-cortical hyperactivity plays a role in anesthesia-induced remote memory impairment. Targeting tau hyperphosphorylation shows promise as a therapeutic strategy to mitigate anesthesia-induced neural network dysfunction and retrograde amnesia in AD.
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Affiliation(s)
- Kai Chen
- Department of AnesthesiologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Riya Gupta
- Barnard College of Columbia UniversityNew YorkNew YorkUSA
| | | | - Meng Cui
- Department of BiologyPurdue UniversityWest LafayetteIndianaUSA
| | - Zhongcong Xie
- Geriatric Anesthesia Research UnitDepartment of AnesthesiaCritical Care and Pain MedicineMassachusetts General Hospital and Harvard Medical SchoolCharlestownMassachusettsUSA
| | - Guang Yang
- Department of AnesthesiologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
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Ohno M. A Strategy for Allowing Earlier Diagnosis and Rigorous Evaluation of BACE1 Inhibitors in Preclinical Alzheimer's Disease. J Alzheimers Dis 2024; 99:431-445. [PMID: 38701146 DOI: 10.3233/jad-231451] [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] [Indexed: 05/05/2024]
Abstract
Given continued failure of BACE1 inhibitor programs at symptomatic and prodromal stages of Alzheimer's disease (AD), clinical trials need to target the earlier preclinical stage. However, trial design is complex in this population with negative diagnosis of classical hippocampal amnesia on standard memory tests. Besides recent advances in brain imaging, electroencephalogram, and fluid-based biomarkers, new cognitive markers should be established for earlier diagnosis that can optimize recruitment to BACE1 inhibitor trials in presymptomatic AD. Notably, accelerated long-term forgetting (ALF) is emerging as a sensitive cognitive measure that can discriminate between asymptomatic individuals with high risks for developing AD and healthy controls. ALF is a form of declarative memory impairment characterized by increased forgetting rates over longer delays (days to months) despite normal storage within the standard delays of testing (20-60 min). Therefore, ALF may represent a harbinger of preclinical dementia and the impairment of systems memory consolidation, during which memory traces temporarily stored in the hippocampus become gradually integrated into cortical networks. This review provides an overview of the utility of ALF in a rational design of next-generation BACE1 inhibitor trials in preclinical AD. I explore potential mechanisms underlying ALF and relevant early-stage biomarkers useful for BACE1 inhibitor evaluation, including synaptic protein alterations, astrocytic dysregulation and neuron hyperactivity in the hippocampal-cortical network. Furthermore, given the physiological role of the isoform BACE2 as an AD-suppressor gene, I also discuss the possible association between the poor selectivity of BACE1 inhibitors and their side effects (e.g., cognitive worsening) in prior clinical trials.
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Affiliation(s)
- Masuo Ohno
- Center for Dementia Research, Nathan Kline Institute, Orangeburg, NY, USA
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Wang W, Sun T. Impact of TRPV1 on Pathogenesis and Therapy of Neurodegenerative Diseases. Molecules 2023; 29:181. [PMID: 38202764 PMCID: PMC10779880 DOI: 10.3390/molecules29010181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/11/2023] [Accepted: 12/11/2023] [Indexed: 01/12/2024] Open
Abstract
Transient receptor potential vanilloid 1 (TRPV1) is a transmembrane and non-selective cation channel protein, which can be activated by various physical and chemical stimuli. Recent studies have shown the strong pathogenetic associations of TRPV1 with neurodegenerative diseases (NDs), in particular Alzheimer's disease (AD), Parkinson's disease (PD) and multiple sclerosis (MS) via regulating neuroinflammation. Therapeutic effects of TRPV1 agonists and antagonists on the treatment of AD and PD in animal models also are emerging. We here summarize the current understanding of TRPV1's effects and its agonists and antagonists as a therapeutic means in neurodegenerative diseases, and highlight future treatment strategies using natural TRPV1 agonists. Developing new targets and applying natural products are becoming a promising direction in the treatment of chronic disorders, especially neurodegenerative diseases.
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Affiliation(s)
| | - Tao Sun
- Center for Precision Medicine, School of Medicine and School of Biomedical Sciences, Huaqiao University, Xiamen 361021, China;
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49
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Keramidis I, McAllister BB, Bourbonnais J, Wang F, Isabel D, Rezaei E, Sansonetti R, Degagne P, Hamel JP, Nazari M, Inayat S, Dudley JC, Barbeau A, Froux L, Paquet ME, Godin AG, Mohajerani MH, De Koninck Y. Restoring neuronal chloride extrusion reverses cognitive decline linked to Alzheimer's disease mutations. Brain 2023; 146:4903-4915. [PMID: 37551444 PMCID: PMC10690023 DOI: 10.1093/brain/awad250] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/23/2023] [Accepted: 07/09/2023] [Indexed: 08/09/2023] Open
Abstract
Disinhibition during early stages of Alzheimer's disease is postulated to cause network dysfunction and hyperexcitability leading to cognitive deficits. However, the underlying molecular mechanism remains unknown. Here we show that, in mouse lines carrying Alzheimer's disease-related mutations, a loss of neuronal membrane potassium-chloride cotransporter KCC2, responsible for maintaining the robustness of GABAA-mediated inhibition, occurs pre-symptomatically in the hippocampus and prefrontal cortex. KCC2 downregulation was inversely correlated with the age-dependent increase in amyloid-β 42 (Aβ42). Acute administration of Aβ42 caused a downregulation of membrane KCC2. Loss of KCC2 resulted in impaired chloride homeostasis. Preventing the decrease in KCC2 using long term treatment with CLP290 protected against deterioration of learning and cortical hyperactivity. In addition, restoring KCC2, using short term CLP290 treatment, following the transporter reduction effectively reversed spatial memory deficits and social dysfunction, linking chloride dysregulation with Alzheimer's disease-related cognitive decline. These results reveal KCC2 hypofunction as a viable target for treatment of Alzheimer's disease-related cognitive decline; they confirm target engagement, where the therapeutic intervention takes place, and its effectiveness.
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Affiliation(s)
- Iason Keramidis
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Graduate Program in Neuroscience, Faculty of Medicine, Université Laval, Québec, QC G1V 0A6, Canada
| | - Brendan B McAllister
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Julien Bourbonnais
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Feng Wang
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Faculty of Dentistry, Université Laval, Québec, QC G1V 0A6, Canada
| | - Dominique Isabel
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Edris Rezaei
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Romain Sansonetti
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Phil Degagne
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Justin P Hamel
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Mojtaba Nazari
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Samsoon Inayat
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Jordan C Dudley
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Annie Barbeau
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Lionel Froux
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
| | - Marie-Eve Paquet
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Department of Biochemistry, Microbiology, and Bio-informatics, Université Laval, Québec, QC G1V 0A6, Canada
| | - Antoine G Godin
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Graduate Program in Neuroscience, Faculty of Medicine, Université Laval, Québec, QC G1V 0A6, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada
| | - Majid H Mohajerani
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Yves De Koninck
- CERVO Brain Research Centre, Quebec Mental Health Institute, Québec, QC G1E 1T2, Canada
- Graduate Program in Neuroscience, Faculty of Medicine, Université Laval, Québec, QC G1V 0A6, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, QC G1V 0A6, Canada
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Dastgheib ZA, Lithgow BJ, Moussavi ZK. Evaluating the Diagnostic Value of Electrovestibulography (EVestG) in Alzheimer's Patients with Mixed Pathology: A Pilot Study. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:2091. [PMID: 38138194 PMCID: PMC10744488 DOI: 10.3390/medicina59122091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/24/2023] [Accepted: 11/26/2023] [Indexed: 12/24/2023]
Abstract
Background and Objectives: Diagnosis of dementia subtypes caused by different brain pathophysiologies, particularly Alzheimer's disease (AD) from AD mixed with levels of cerebrovascular disease (CVD) symptomology (AD-CVD), is challenging due to overlapping symptoms. In this pilot study, the potential of Electrovestibulography (EVestG) for identifying AD, AD-CVD, and healthy control populations was investigated. Materials and Methods: A novel hierarchical multiclass diagnostic algorithm based on the outcomes of its lower levels of binary classifications was developed using data of 16 patients with AD, 13 with AD-CVD, and 24 healthy age-matched controls, and then evaluated on a blind testing dataset made up of a new population of 12 patients diagnosed with AD, 9 with AD-CVD, and 8 healthy controls. Multivariate analysis was run to test the between population differences while controlling for sex and age covariates. Results: The accuracies of the multiclass diagnostic algorithm were found to be 85.7% and 79.6% for the training and blind testing datasets, respectively. While a statistically significant difference was found between the populations after accounting for sex and age, no significant effect was found for sex or age covariates. The best characteristic EVestG features were extracted from the upright sitting and supine up/down stimulus responses. Conclusions: Two EVestG movements (stimuli) and their most informative features that are best selective of the above-populations' separations were identified, and a hierarchy diagnostic algorithm was developed for three-way classification. Given that the two stimuli predominantly stimulate the otholithic organs, physiological and experimental evidence supportive of the results are presented. Disruptions of inhibition associated with GABAergic activity might be responsible for the changes in the EVestG features.
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Affiliation(s)
| | | | - Zahra K. Moussavi
- Diagnostic and Neurological Processing Research Laboratory, Biomedical Engineering Program, University of Manitoba, Riverview Health Centre, Winnipeg, MB R3L 2P4, Canada; (Z.A.D.); (B.J.L.)
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