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Lee H, Fu JF, Gaudet K, Bryant AG, Price JC, Bennett RE, Johnson KA, Hyman BT, Hedden T, Salat DH, Yen YF, Huang SY. Aberrant vascular architecture in the hippocampus correlates with tau burden in mild cognitive impairment and Alzheimer's disease. J Cereb Blood Flow Metab 2024; 44:787-800. [PMID: 38000018 DOI: 10.1177/0271678x231216144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2023]
Abstract
Cerebrovascular dysfunction is a significant contributor to Alzheimer's disease (AD) progression. AD mouse models show altered capillary morphology, density, and diminished blood flow in areas of tau and beta-amyloid accumulation. The purpose of this study was to examine alterations in vascular structure and their contributions to perfusion deficits in the hippocampus in AD and mild cognitive impairment (MCI). Seven individuals with AD and MCI (1 AD/6 MCI), nine cognitively intact older healthy adults, and seven younger healthy adults underwent pseudo-continuous arterial spin labeling (PCASL) and gradient-echo/spin-echo (GESE) dynamic susceptibility contrast (DSC) MRI. Cerebral blood flow (CBF), cerebral blood volume, relative vessel size index (rVSI), and mean vessel density were calculated from model fitting. Lower CBF from PCASL and SE DSC MRI was observed in the hippocampus of AD/MCI group. rVSI in the hippocampus of the AD/MCI group was larger than that of the two healthy groups (FDR-P = 0.02). No difference in vessel density was detected between the groups. We also explored relationship of tau burden from 18F-flortaucipir positron emission tomography and vascular measures from MRI. Tau burden was associated with larger vessel size and lower CBF in the hippocampus. We postulate that larger vessel size may be associated with vascular alterations in AD/MCI.
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Affiliation(s)
- Hansol Lee
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Jessie Fanglu Fu
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Kyla Gaudet
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Annie G Bryant
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Julie C Price
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Rachel E Bennett
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Keith A Johnson
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
- Center for Alzheimer Research and Treatment, Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Trey Hedden
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - David H Salat
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Yi-Fen Yen
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Susie Y Huang
- Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
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Hoglund Z, Ruiz-Uribe N, del Sastre E, Woost B, Bailey J, Hyman BT, Zwang T, Bennett RE. Brain Vasculature Accumulates Tau and Is Spatially Related to Tau Tangle Pathology in Alzheimer's Disease. bioRxiv 2024:2024.01.27.577088. [PMID: 38328111 PMCID: PMC10849642 DOI: 10.1101/2024.01.27.577088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Insoluble pathogenic proteins accumulate along blood vessels in conditions of cerebral amyloid angiopathy (CAA), exerting a toxic effect on vascular cells and impacting cerebral homeostasis. In this work we provide new evidence from three-dimensional human brain histology that tau protein, the main component of neurofibrillary tangles, can similarly accumulate along brain vascular segments. We quantitatively assessed n=6 Alzheimer's disease (AD), and n=6 normal aging control brains and saw that tau-positive blood vessel segments were present in all AD cases. Tau-positive vessels are enriched for tau at levels higher than the surrounding tissue and appear to affect arterioles across cortical layers (I-V). Further, vessels isolated from these AD tissues were enriched for N-terminal tau and tau phosphorylated at T181 and T217. Importantly, tau-positive vessels are associated with local areas of increased tau neurofibrillary tangles. This suggests that accumulation of tau around blood vessels may reflect a local clearance failure. In sum, these data indicate tau, like amyloid beta, accumulates along blood vessels and may exert a significant influence on vasculature in the setting of AD.
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Affiliation(s)
- Zachary Hoglund
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Nancy Ruiz-Uribe
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Eric del Sastre
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Benjamin Woost
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Joshua Bailey
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
| | - Bradley T. Hyman
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Theodore Zwang
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Rachel E. Bennett
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
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3
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Lathuiliere A, Jo Y, Perbet R, Donahue C, Commins C, Quittot N, Fan Z, Bennett RE, Hyman BT. Specific detection of tau seeding activity in Alzheimer's disease using rationally designed biosensor cells. Mol Neurodegener 2023; 18:53. [PMID: 37553663 PMCID: PMC10408046 DOI: 10.1186/s13024-023-00643-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 07/28/2023] [Indexed: 08/10/2023] Open
Abstract
BACKGROUND The prion-like propagation of tau in neurodegenerative disorders implies that misfolded pathological tau can recruit the normal protein and template its aggregation. Here, we report the methods for the development of sensitive biosensor cell lines for the detection of tau seeding activity. RESULTS We performed the rational design of novel tau probes based on the current structural knowledge of pathological tau aggregates in Alzheimer's disease. We generated Förster resonance energy transfer (FRET)-based biosensor stable cell lines and characterized their sensitivity, specificity, and overall ability to detect bioactive tau in human samples. As compared to the reference biosensor line, the optimized probe design resulted in an increased efficiency in the detection of tau seeding. The increased sensitivity allowed for the detection of lower amount of tau seeding competency in human brain samples, while preserving specificity for tau seeds found in Alzheimer's disease. CONCLUSIONS This next generation of FRET-based biosensor cells is a novel tool to study tau seeding activity in Alzheimer's disease human samples, especially in samples with low levels of seeding activity, which may help studying early tau-related pathological events.
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Affiliation(s)
- Aurelien Lathuiliere
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
- Harvard Medical School, Boston, MA, USA
- Memory Center, Department of Rehabilitation and Geriatrics, Geneva University Hospital and University of Geneva, Geneva, Switzerland
| | - Youhwa Jo
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
| | - Romain Perbet
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
- Harvard Medical School, Boston, MA, USA
| | - Cameron Donahue
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
| | - Caitlin Commins
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
| | - Noé Quittot
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
- Harvard Medical School, Boston, MA, USA
| | - Zhanyun Fan
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
| | - Rachel E Bennett
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA
- Harvard Medical School, Boston, MA, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, 114 16Th Street, Charlestown, MA, 02129, USA.
- Harvard Medical School, Boston, MA, USA.
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4
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Ramirez SH, Hale JF, McCarthy S, Lino Cardenas CL, Dona KNUG, Hanlon KS, Hudry E, Cruz DDL, Ng C, Das S, Nguyen DM, Nammour J, Bennett RE, Andrews AM, Musolino PL, Maguire CA. An Engineered Adeno-Associated Virus Capsid Mediates Efficient Transduction of Pericytes and Smooth Muscle Cells of the Brain Vasculature. Hum Gene Ther 2023; 34:682-696. [PMID: 37376759 PMCID: PMC10457656 DOI: 10.1089/hum.2022.211] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Neurodegeneration and cerebrovascular disease share an underlying microvascular dysfunction that may be remedied by selective transgene delivery. To date, limited options exist in which cellular components of the brain vasculature can be effectively targeted by viral vector therapeutics. In this study, we characterize the first engineered adeno-associated virus (AAV) capsid mediating high transduction of cerebral vascular pericytes and smooth muscle cells (SMCs). We performed two rounds of in vivo selection with an AAV capsid scaffold displaying a heptamer peptide library to isolate capsids that traffic to the brain after intravenous delivery. One identified capsid, termed AAV-PR, demonstrated high transduction of the brain vasculature, in contrast to the parental capsid, AAV9, which transduces mainly neurons and astrocytes. Further analysis using tissue clearing, volumetric rendering, and colocalization revealed that AAV-PR enabled high transduction of cerebral pericytes located on small-caliber vessels and SMCs in the larger arterioles and penetrating pial arteries. Analysis of tissues in the periphery indicated that AAV-PR also transduced SMCs in large vessels associated with the systemic vasculature. AAV-PR was also able to transduce primary human brain pericytes with higher efficiency than AAV9. Compared with previously published AAV capsids tropisms, AAV-PR represents the first capsid to allow for effective transduction of brain pericytes and SMCs and offers the possibility of genetically modulating these cell types in the context of neurodegeneration and other neurological diseases.
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Affiliation(s)
- Servio H. Ramirez
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
- Shriners Hospitals Pediatric Research Center, Philadelphia, Pennsylvania, USA
| | - Jonathan F. Hale
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
- Shriners Hospitals Pediatric Research Center, Philadelphia, Pennsylvania, USA
| | - Siobhan McCarthy
- Center for Genomic Medicine; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Christian L. Lino Cardenas
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Cardiology; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Kalpani N. Udeni Galpayage Dona
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
- Shriners Hospitals Pediatric Research Center, Philadelphia, Pennsylvania, USA
| | - Killian S. Hanlon
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Eloise Hudry
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Demitri De La Cruz
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
- Molecular Neurogenetics Unit, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Carrie Ng
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
- Molecular Neurogenetics Unit, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Sabyasachi Das
- Center for Genomic Medicine; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Diane M. Nguyen
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Josette Nammour
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
- Molecular Neurogenetics Unit, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Rachel E. Bennett
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Allison M. Andrews
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
- Shriners Hospitals Pediatric Research Center, Philadelphia, Pennsylvania, USA
| | - Patricia L. Musolino
- Center for Genomic Medicine; Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Casey A. Maguire
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology; Massachusetts General Hospital, Boston, Massachusetts, USA
- Molecular Neurogenetics Unit, Massachusetts General Hospital, Charlestown, Massachusetts, USA
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5
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Zwang TJ, Woost B, Bailey J, Hoglund Z, Richardson DS, Bennett RE, Hyman BT. Spatial characterization of tangle-bearing neurons and ghost tangles in the human inferior temporal gyrus with three-dimensional imaging. Brain Commun 2023; 5:fcad130. [PMID: 37324243 PMCID: PMC10263274 DOI: 10.1093/braincomms/fcad130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/06/2023] [Accepted: 04/17/2023] [Indexed: 06/17/2023] Open
Abstract
Studies of post-mortem human tissue provide insight into pathological processes, but are inherently limited by practical considerations that limit the scale at which tissue can be examined, and the obvious issue that the tissue reflects only one time point in a continuous disease process. We approached this problem by adapting new tissue clearance techniques to an entire cortical area of human brain, which allows surveillance of hundreds of thousands of neurons throughout the depth of the entire cortical thickness. This approach allows detection of 'rare' events that may be difficult to detect in standard 5 micrometre-thick paraffin sections. For example, it is well established that neurofibrillary tangles begin within a neuron, and ultimately, in at least some instances, persist in the brain even after the neuron has died. These are referred to as 'ghost tangles', a term that appropriately implies their 'difficult to see' ephemeral qualities. We set out to find ghost tangles as one example of the power of the tissue clearance/image analysis techniques to detect rare events, and to learn what happens at the end-point of a tangle's life history. We were able to identify 8103 tau tangles, 132 465 neurons and 299 640 nuclei in tissue samples from three subjects with severe Alzheimer's disease (Braak V-VI) and 4 tau tangles, 200 447 neurons and 462 715 nuclei in tissue samples from three subjects with no significant tau pathology (Braak 0-I). Among these data, we located 57 ghost tangles, which makes them only 0.7% of the total tau tangles observed. We found that ghost tangles are more likely to be found in cortical layers 3 and 5 (49/57), with a select few scattered across other layers 1, 2, 4 and 6. This ability to find rare events, such as ghost tangles, in large enough quantities to statistically test their distribution exemplifies how tissue clearing can be used as a powerful tool for studying selective vulnerability or resilience to pathology across brain regions.
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Affiliation(s)
- Theodore J Zwang
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Massachusetts Alzheimer’s Disease Research Center, Charlestown, MA, USA
| | - Benjamin Woost
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
| | - Joshua Bailey
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
| | - Zachary Hoglund
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
| | - Douglas S Richardson
- Department of Molecular and Cellular Biology and Harvard Center for Biological Imaging, Harvard University, Cambridge, MA, USA
| | - Rachel E Bennett
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Massachusetts Alzheimer’s Disease Research Center, Charlestown, MA, USA
| | - Bradley T Hyman
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Massachusetts Alzheimer’s Disease Research Center, Charlestown, MA, USA
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6
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Zwang TJ, Bennett RE, Lysandrou M, Woost B, Zhang A, Lieber CM, Richardson DS, Hyman BT. Tissue libraries enable rapid determination of conditions that preserve antibody labeling in cleared mouse and human tissue. eLife 2023; 12:e84112. [PMID: 36656755 PMCID: PMC9889093 DOI: 10.7554/elife.84112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 01/18/2023] [Indexed: 01/20/2023] Open
Abstract
Difficulty achieving complete, specific, and homogenous staining is a major bottleneck preventing the widespread use of tissue clearing techniques to image large volumes of human tissue. In this manuscript, we describe a procedure to rapidly design immunostaining protocols for antibody labeling of cleared brain tissue. We prepared libraries of 0.5-1.0 mm thick tissue sections that are fixed, pre-treated, and cleared via similar, but different procedures to optimize staining conditions for a panel of antibodies. Results from a library of mouse tissue correlate well with results from a similarly prepared library of human brain tissue, suggesting mouse tissue is an adequate substitute for protocol optimization. These data show that procedural differences do not influence every antibody-antigen pair in the same way, and minor changes can have deleterious effects, therefore, optimization should be conducted for each target. The approach outlined here will help guide researchers to successfully label a variety of targets, thus removing a major hurdle to accessing the rich 3D information available in large, cleared human tissue volumes.
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Affiliation(s)
- Theodore J Zwang
- Department of Neurology, Massachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Harvard Medical SchoolBostonUnited States
- Massachusetts Alzheimer’s Disease Research CenterCharlestownUnited States
| | - Rachel E Bennett
- Department of Neurology, Massachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Harvard Medical SchoolBostonUnited States
- Massachusetts Alzheimer’s Disease Research CenterCharlestownUnited States
| | - Maria Lysandrou
- Department of Neurology, Massachusetts General Hospital, Harvard Medical SchoolBostonUnited States
| | - Benjamin Woost
- Department of Neurology, Massachusetts General Hospital, Harvard Medical SchoolBostonUnited States
| | - Anqi Zhang
- Department of Chemical Engineering, Stanford UniversityStanfordUnited States
| | - Charles M Lieber
- Department of Chemistry and Chemical Biology, Harvard UniversityCambridgeUnited States
| | - Douglas S Richardson
- Department of Molecular and Cellular Biology and Harvard Center for Biological Imaging, Harvard UniversityCambridgeUnited States
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Harvard Medical SchoolBostonUnited States
- Massachusetts Alzheimer’s Disease Research CenterCharlestownUnited States
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7
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Kwon T, Lin G, Chancellor SE, Wachter A, Abdourahman A, Bennett RE, Liao F, Pastika T, Tamm JA, Venkat N, Yanamandra K, Grinberg Y, Kummer MP, Das S, Dellovade TL, Karran EH, Talanian RV, Biber K, Ried JS, Serrano‐Pozo A, Langlois X, Hyman BT. Tau pathology vulnerable neuronal subpopulation in Alzheimer’s disease. Alzheimers Dement 2022. [DOI: 10.1002/alz.063430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | - Gen Lin
- AbbVie Deutschland GmbH & Co. KG Ludwigshafen Germany
| | | | | | | | - Rachel E Bennett
- Massachusetts General Hospital Boston MA USA
- Harvard Medical School Boston MA USA
| | - Fan Liao
- AbbVie, Cambridge Research Center Cambridge MA USA
| | | | | | | | | | | | | | - Sudeshna Das
- Massachusetts General Hospital Boston MA USA
- Harvard Medical School Cambridge MA USA
- Massachusetts Alzheimer’s Disease Research Center Charlestown MA USA
| | | | | | | | - Knut Biber
- AbbVie Deutschland GmbH & Co. KG Ludwigshafen Germany
| | - Janina S Ried
- AbbVie Deutschland GmbH & Co. KG Ludwigshafen Germany
| | - Alberto Serrano‐Pozo
- Massachusetts General Hospital Boston MA USA
- Harvard Medical School Boston MA USA
- Massachusetts Alzheimer’s Disease Research Center Charlestown MA USA
| | | | - Bradley T. Hyman
- Massachusetts General Hospital Boston MA USA
- Harvard Medical School Boston MA USA
- Massachusetts Alzheimer’s Disease Research Center Charlestown MA USA
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8
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Jackson RJ, Meltzer JC, Nguyen H, Commins C, Bennett RE, Hudry E, Hyman BT. APOE4 derived from astrocytes leads to blood-brain barrier impairment. Brain 2021; 145:3582-3593. [PMID: 34957486 PMCID: PMC9586546 DOI: 10.1093/brain/awab478] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/25/2021] [Accepted: 12/01/2021] [Indexed: 02/04/2023] Open
Abstract
Apolipoprotein E (ApoE) is a multifaceted secreted molecule synthesized in the CNS by astrocytes and microglia, and in the periphery largely by the liver. ApoE has been shown to impact the integrity of the blood-brain barrier, and, in humans, the APOE4 allele of the gene is reported to lead to a leaky blood-brain barrier. We used allele specific knock-in mice expressing each of the common (human) ApoE alleles, and longitudinal multiphoton intravital microscopy, to directly monitor the impact of various ApoE isoforms on blood-brain barrier integrity. We found that humanized APOE4, but not APOE2 or APOE3, mice show a leaky blood-brain barrier, increased MMP9, impaired tight junctions, and reduced astrocyte end-foot coverage of blood vessels. Removal of astrocyte-produced ApoE4 led to the amelioration of all phenotypes while the removal of astrocyte-produced ApoE3 had no effect on blood-brain barrier integrity. This work shows a cell specific gain of function effect of ApoE4 in the dysfunction of the BBB and implicates astrocyte production of ApoE4, possibly as a function of astrocytic end foot interactions with vessels, as a key regulator of the integrity of the blood-brain barrier.
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Affiliation(s)
- Rosemary J Jackson
- Alzheimer Research Unit, The Massachusetts General Hospital Institute for Neurodegenerative Disease, Charlestown, MA, USA,Department of Neurology, The Massachusetts General Hospital and NeuroDiscovery Center, Harvard Medical School, Boston, MA, USA
| | | | | | - Caitlin Commins
- Alzheimer Research Unit, The Massachusetts General Hospital Institute for Neurodegenerative Disease, Charlestown, MA, USA,Department of Neurology, The Massachusetts General Hospital and NeuroDiscovery Center, Harvard Medical School, Boston, MA, USA
| | - Rachel E Bennett
- Alzheimer Research Unit, The Massachusetts General Hospital Institute for Neurodegenerative Disease, Charlestown, MA, USA,Department of Neurology, The Massachusetts General Hospital and NeuroDiscovery Center, Harvard Medical School, Boston, MA, USA
| | - Eloise Hudry
- Alzheimer Research Unit, The Massachusetts General Hospital Institute for Neurodegenerative Disease, Charlestown, MA, USA,Department of Neurology, The Massachusetts General Hospital and NeuroDiscovery Center, Harvard Medical School, Boston, MA, USA,Novartis Institute for Biomedical Research, Cambridge, MA, USA
| | - Bradley T Hyman
- Correspondence to: Bradley Hyman Massachusetts General Hospital MIND Institute 114 16th Street, Charlestown, 02129 MA, USA E-mail:
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9
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Dehkordi SK, Walker J, Sah E, Bennett E, Atrian F, Frost B, Woost B, Bennett RE, Orr TC, Zhou Y, Andhey PS, Colonna M, Sudmant PH, Xu P, Wang M, Zhang B, Zare H, Orr ME. Profiling senescent cells in human brains reveals neurons with CDKN2D/p19 and tau neuropathology. Nat Aging 2021; 1:1107-1116. [PMID: 35531351 PMCID: PMC9075501 DOI: 10.1038/s43587-021-00142-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 10/26/2021] [Indexed: 12/20/2022]
Abstract
Senescent cells contribute to pathology and dysfunction in animal models1. Their sparse distribution and heterogenous phenotype have presented challenges for detecting them in human tissues. We developed a senescence eigengene approach to identify these rare cells within large, diverse populations of postmortem human brain cells. Eigengenes are useful when no single gene reliably captures a phenotype, like senescence; they also help to reduce noise, which is important in large transcriptomic datasets where subtle signals from low-expressing genes can be lost. Each of our eigengenes detected ~2% senescent cells from a population of ~140,000 single nuclei derived from 76 postmortem human brains with various levels of Alzheimer's disease (AD) pathology. More than 97% of the senescent cells were excitatory neurons and overlapped with tau-containing neurofibrillary tangles (NFTs). Cyclin dependent kinase inhibitor 2D (CDKN2D/p19) was predicted as the most significant contributor to the primary senescence eigengene. RNAscope and immunofluorescence confirmed its elevated expression in AD brain tissue whereby p19-expressing neurons had 1.8-fold larger nuclei and significantly more cells with lipofuscin than p19-negative neurons. These hallmark senescence phenotypes were further elevated in the presence of NFTs. Collectively, CDKN2D/p19-expressing neurons with NFTs represent a unique cellular population in human AD with a senescence phenotype. The eigengenes developed may be useful in future senescence profiling studies as they accurately identified senescent cells in snRNASeq datasets and predicted biomarkers for histological investigation.
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Affiliation(s)
- Shiva Kazempour Dehkordi
- Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases, 7400 Merton Minter, San Antonio, TX, 78229, USA
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Jamie Walker
- Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases, 7400 Merton Minter, San Antonio, TX, 78229, USA
| | - Eric Sah
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Emma Bennett
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Farzaneh Atrian
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas, USA
- Sam and Ann Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Bess Frost
- Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases, 7400 Merton Minter, San Antonio, TX, 78229, USA
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas, USA
- Sam and Ann Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Benjamin Woost
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Rachel E. Bennett
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Timothy C. Orr
- Department of Healthcare Innovations, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Yingyue Zhou
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Prabhakar S. Andhey
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Peter H. Sudmant
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Peng Xu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Minghui Wang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
- Department of Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Habil Zare
- Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases, 7400 Merton Minter, San Antonio, TX, 78229, USA
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Miranda E. Orr
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
- Salisbury VA Medical Center, Salisbury, NC, USA
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10
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Bryant AG, Manhard MK, Salat DH, Rosen BR, Hyman BT, Johnson KA, Huang S, Bennett RE, Yen YF. Heterogeneity of Tau Deposition and Microvascular Involvement in MCI and AD. Curr Alzheimer Res 2021; 18:711-720. [PMID: 34825871 PMCID: PMC8822690 DOI: 10.2174/1567205018666211126113904] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/10/2021] [Accepted: 08/28/2021] [Indexed: 11/23/2022]
Abstract
Background Reduced cerebrovascular function and accumulation of tau pathology are key components of cognitive decline in Alzheimer’s disease (AD). Recent multimodal neuroimaging studies show a correlation between cortical tau accumulation and reduced cerebral perfusion. However, animal models predict that tau exerts capillary-level changes that may not be fully captured by standard imaging protocols. Objective Using newly-developed magnetic resonance imaging (MRI) technology to measure capillary-specific perfusion parameters, we examined a series of mild cognitive impairment (MCI) and AD patients with tau positron emission tomography (PET) to observe whole-brain capillary perfusion alterations and their association with tau deposition. Methods Seven subjects with MCI or AD received Flortaucipir PET to measure tau deposition and spin-echo dynamic susceptibility contrast (SE-DSC) MRI to measure microvascular perfusion (<10μm radius vessels). Gradient-echo (GE) DSC and pseudocontinuous arterial spin labeling (PCASL) MRI were also acquired to assess macrovascular perfusion. Tau PET, microvascular perfusion, and cortical thickness maps were visually inspected in volumetric slices and on cortical surface projections. Results High tau PET signal was generally observed in the lateral temporal and parietal cortices, with uptake in the occipital cortex in one subject. Global blood flow measured by PCASL was reduced with increasing tau burden, which was consistent with previous studies. Tau accumulation was spatially associated with variable patterns of microvascular cerebral blood flow (CBF) and oxygen extraction fraction (OEF) in the cortex and with increased capillary transit heterogeneity (CTH) in adjacent periventricular white matter, independent of amyloid-β status. Conclusion Although macrovascular perfusion generally correlated with tau deposition at the whole-cortex level, regional changes in microvascular perfusion were not uniformly associated with either tau pathology or cortical atrophy. This work highlights the heterogeneity of AD-related brain changes and the challenges of implementing therapeutic interventions to improve cerebrovascular function.
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Affiliation(s)
- Annie G Bryant
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Mary K Manhard
- Department of Radiology, Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States
| | - David H Salat
- Department of Radiology, Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States
| | - Bruce R Rosen
- Department of Radiology, Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States
| | - Bradley T Hyman
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Keith A Johnson
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Susie Huang
- Department of Radiology, Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States
| | - Rachel E Bennett
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Yi-Fen Yen
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
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11
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Wegmann S, DeVos SL, Zeitler B, Marlen K, Bennett RE, Perez-Rando M, MacKenzie D, Yu Q, Commins C, Bannon RN, Corjuc BT, Chase A, Diez L, Nguyen HOB, Hinkley S, Zhang L, Goodwin A, Ledeboer A, Lam S, Ankoudinova I, Tran H, Scarlott N, Amora R, Surosky R, Miller JC, Robbins AB, Rebar EJ, Urnov FD, Holmes MC, Pooler AM, Riley B, Zhang HS, Hyman BT. Persistent repression of tau in the brain using engineered zinc finger protein transcription factors. Sci Adv 2021; 7:7/12/eabe1611. [PMID: 33741591 PMCID: PMC7978433 DOI: 10.1126/sciadv.abe1611] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 02/05/2021] [Indexed: 05/12/2023]
Abstract
Neuronal tau reduction confers resilience against β-amyloid and tau-related neurotoxicity in vitro and in vivo. Here, we introduce a novel translational approach to lower expression of the tau gene MAPT at the transcriptional level using gene-silencing zinc finger protein transcription factors (ZFP-TFs). Following a single administration of adeno-associated virus (AAV), either locally into the hippocampus or intravenously to enable whole-brain transduction, we selectively reduced tau messenger RNA and protein by 50 to 80% out to 11 months, the longest time point studied. Sustained tau lowering was achieved without detectable off-target effects, overt histopathological changes, or molecular alterations. Tau reduction with AAV ZFP-TFs was able to rescue neuronal damage around amyloid plaques in a mouse model of Alzheimer's disease (APP/PS1 line). The highly specific, durable, and controlled knockdown of endogenous tau makes AAV-delivered ZFP-TFs a promising approach for the treatment of tau-related human brain diseases.
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Affiliation(s)
- Susanne Wegmann
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA.
- German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | - Sarah L DeVos
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | | | | | - Rachel E Bennett
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Marta Perez-Rando
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Danny MacKenzie
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Qi Yu
- Sangamo Therapeutics Inc., Richmond, CA 94804, USA
| | - Caitlin Commins
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Riley N Bannon
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Bianca T Corjuc
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Alison Chase
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | - Lisa Diez
- German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
| | | | | | - Lei Zhang
- Sangamo Therapeutics Inc., Richmond, CA 94804, USA
| | | | | | - Stephen Lam
- Sangamo Therapeutics Inc., Richmond, CA 94804, USA
| | | | - Hung Tran
- Sangamo Therapeutics Inc., Richmond, CA 94804, USA
| | | | | | | | | | - Ashley B Robbins
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA
| | | | | | | | - Amy M Pooler
- Sangamo Therapeutics Inc., Richmond, CA 94804, USA
| | - Brigit Riley
- Sangamo Therapeutics Inc., Richmond, CA 94804, USA
| | | | - Bradley T Hyman
- Massachusetts General Hospital, Massachusetts Institute of Neurodegenerative Disease, Charlestown, MA 02129, USA.
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12
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Perez-Rando M, Dujardin S, Bennett RE, Commins C, Nibhanupudy T, Hyman BT. Synaptic and metabolic gene expression alterations in neurons that are recipients of proteopathic tau seeds. Acta Neuropathol Commun 2020; 8:168. [PMID: 33076986 PMCID: PMC7574323 DOI: 10.1186/s40478-020-01049-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 10/02/2020] [Indexed: 01/07/2023] Open
Abstract
Recent studies suggest that misfolded tau molecules can be released, and taken up by adjacent neurons, propagating proteopathic seeds across neural systems. Yet critical to understanding whether tau propagation is relevant in pathophysiology of disease would be to learn if it alters neuronal properties. We utilized high resolution multi-color in situ hybridization technology, RNAScope, in a well-established tau transgenic animal, and found that a subset of neurons in the cortex do not appear to express the transgene, but do develop phospho-tau positive inclusions, consistent with having received tau seeds. Recipient neurons show decreases in their expression of synaptophysin, CAMKIIα, and mouse tau in both young and old animals. These results contrast with neurons that develop tau aggregates and also overexpress the transgene, which have few changes in expression of metabolic and synaptic markers. Taken together, these results strongly suggest that tau propagation impacts neuronal functional integrity.
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Affiliation(s)
- Marta Perez-Rando
- grid.32224.350000 0004 0386 9924Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital, Building 114, Room 2009, Charlestown, MA 02129 USA ,grid.38142.3c000000041936754XHarvard Medical School, Boston, MA USA
| | - Simon Dujardin
- grid.32224.350000 0004 0386 9924Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital, Building 114, Room 2009, Charlestown, MA 02129 USA ,grid.38142.3c000000041936754XHarvard Medical School, Boston, MA USA
| | - Rachel E. Bennett
- grid.32224.350000 0004 0386 9924Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital, Building 114, Room 2009, Charlestown, MA 02129 USA ,grid.38142.3c000000041936754XHarvard Medical School, Boston, MA USA
| | - Caitlin Commins
- grid.32224.350000 0004 0386 9924Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital, Building 114, Room 2009, Charlestown, MA 02129 USA
| | - Tara Nibhanupudy
- grid.32224.350000 0004 0386 9924Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital, Building 114, Room 2009, Charlestown, MA 02129 USA
| | - Bradley T. Hyman
- grid.32224.350000 0004 0386 9924Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital, Building 114, Room 2009, Charlestown, MA 02129 USA ,grid.38142.3c000000041936754XHarvard Medical School, Boston, MA USA
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13
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Bryant AG, Hu M, Carlyle BC, Arnold SE, Frosch MP, Das S, Hyman BT, Bennett RE. Cerebrovascular Senescence Is Associated With Tau Pathology in Alzheimer's Disease. Front Neurol 2020; 11:575953. [PMID: 33041998 PMCID: PMC7525127 DOI: 10.3389/fneur.2020.575953] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/12/2020] [Indexed: 12/21/2022] Open
Abstract
Alzheimer's Disease (AD) is associated with neuropathological changes, including aggregation of tau neurofibrillary tangles (NFTs) and amyloid-beta plaques. Mounting evidence indicates that vascular dysfunction also plays a key role in the pathogenesis and progression of AD, in part through endothelial dysfunction. Based on findings in animal models that tau pathology induces vascular abnormalities and cellular senescence, we hypothesized that tau pathology in the human AD brain leads to vascular senescence. To explore this hypothesis, we isolated intact microvessels from the dorsolateral prefrontal cortex (PFC, BA9) from 16 subjects with advanced Braak stages (Braak V/VI, B3) and 12 control subjects (Braak 0/I/II, B1), and quantified expression of 42 genes associated with senescence, cell adhesion, and various endothelial cell functions. Genes associated with endothelial senescence and leukocyte adhesion, including SERPINE1 (PAI-1), CXCL8 (IL8), CXCL1, CXCL2, ICAM-2, and TIE1, were significantly upregulated in B3 microvessels after adjusting for sex and cerebrovascular pathology. In particular, the senescence-associated secretory phenotype genes SERPINE1 and CXCL8 were upregulated by more than 2-fold in B3 microvessels after adjusting for sex, cerebrovascular pathology, and age at death. Protein quantification data from longitudinal plasma samples for a subset of 13 (n = 9 B3, n = 4 B1) subjects showed no significant differences in plasma senescence or adhesion-associated protein levels, suggesting that these changes were not associated with systemic vascular alterations. Future investigations of senescence biomarkers in both the peripheral and cortical vasculature could further elucidate links between tau pathology and vascular changes in human AD.
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Affiliation(s)
- Annie G Bryant
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Miwei Hu
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Becky C Carlyle
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Steven E Arnold
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Matthew P Frosch
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States.,Department of Pathology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Sudeshna Das
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Bradley T Hyman
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
| | - Rachel E Bennett
- Department of Neurology, Harvard Medical School, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, MA, United States
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14
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Bennett RE, Hu M, Fernandes A, Perez-Rando M, Robbins A, Kamath T, Dujardin S, Hyman BT. Tau reduction in aged mice does not impact Microangiopathy. Acta Neuropathol Commun 2020; 8:137. [PMID: 32811565 PMCID: PMC7436970 DOI: 10.1186/s40478-020-01014-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 11/30/2022] Open
Abstract
Microangiopathy, including proliferation of small diameter capillaries, increasing vessel tortuosity, and increased capillary blockage by leukocytes, was previously observed in the aged rTg4510 mouse model. Similar gene expression changes related to angiogenesis were observed in both rTg4510 and Alzheimer's disease (AD). It is uncertain if tau is directly responsible for these vascular changes by interacting directly with microvessels, and/or if it contributes indirectly via neurodegeneration and concurrent neuronal loss and inflammation. To better understand the nature of tau-related microangiopathy in human AD and in tau mice, we isolated capillaries and observed that bioactive soluble tau protein could be readily detected in association with vasculature. To examine whether this soluble tau is directly responsible for the microangiopathic changes, we made use of the tetracycline-repressible gene expression cassette in the rTg4510 mouse model and measured vascular pathology following tau reduction. These data suggest that reduction of tau is insufficient to alter established microvascular complications including morphological alterations, enhanced expression of inflammatory genes involved in leukocyte adherence, and blood brain barrier compromise. These data imply that 1) soluble bioactive tau surprisingly accumulates at the blood brain barrier in human brain and in mouse models, and 2) the morphological and molecular phenotype of microvascular disturbance does not resolve with reduction of whole brain soluble tau. Additional consideration of vascular-directed therapies and strategies that target tau in the vascular space may be required to restore normal function in neurodegenerative disease.
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Affiliation(s)
- Rachel E Bennett
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA.
| | - Miwei Hu
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Analiese Fernandes
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Marta Perez-Rando
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Ashley Robbins
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Tarun Kamath
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Simon Dujardin
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Bradley T Hyman
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
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15
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Hanlon KS, Meltzer JC, Buzhdygan T, Cheng MJ, Sena-Esteves M, Bennett RE, Sullivan TP, Razmpour R, Gong Y, Ng C, Nammour J, Maiz D, Dujardin S, Ramirez SH, Hudry E, Maguire CA. Selection of an Efficient AAV Vector for Robust CNS Transgene Expression. Mol Ther Methods Clin Dev 2019; 15:320-332. [PMID: 31788496 PMCID: PMC6881693 DOI: 10.1016/j.omtm.2019.10.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 10/17/2019] [Indexed: 12/17/2022]
Abstract
Adeno-associated virus (AAV) capsid libraries have generated improved transgene delivery vectors. We designed an AAV library construct, iTransduce, that combines a peptide library on the AAV9 capsid with a Cre cassette to enable sensitive detection of transgene expression. After only two selection rounds of the library delivered intravenously in transgenic mice carrying a Cre-inducible fluorescent protein, we flow sorted fluorescent cells from brain, and DNA sequencing revealed two dominant capsids. One of the capsids, termed AAV-F, mediated transgene expression in the brain cortex more than 65-fold (astrocytes) and 171-fold (neurons) higher than the parental AAV9. High transduction efficiency was sex-independent and sustained in two mouse strains (C57BL/6 and BALB/c), making it a highly useful capsid for CNS transduction of mice. Future work in large animal models will test the translation potential of AAV-F.
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Affiliation(s)
- Killian S Hanlon
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.,Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129.,Harvard Medical School, Boston, MA 02115, USA
| | - Jonah C Meltzer
- Harvard Medical School, Boston, MA 02115, USA.,Alzheimer's Disease Research Laboratory, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Tetyana Buzhdygan
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Shriners Hospital's Pediatric Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Ming J Cheng
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129.,Harvard Medical School, Boston, MA 02115, USA
| | | | - Rachel E Bennett
- Harvard Medical School, Boston, MA 02115, USA.,Alzheimer's Disease Research Laboratory, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Timothy P Sullivan
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Shriners Hospital's Pediatric Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Roshanak Razmpour
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Shriners Hospital's Pediatric Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Yi Gong
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129.,Harvard Medical School, Boston, MA 02115, USA
| | - Carrie Ng
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129.,Harvard Medical School, Boston, MA 02115, USA
| | - Josette Nammour
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129.,Harvard Medical School, Boston, MA 02115, USA
| | - Daniela Maiz
- Harvard Medical School, Boston, MA 02115, USA.,Alzheimer's Disease Research Laboratory, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Simon Dujardin
- Harvard Medical School, Boston, MA 02115, USA.,Alzheimer's Disease Research Laboratory, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Servio H Ramirez
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Shriners Hospital's Pediatric Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.,Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Eloise Hudry
- Harvard Medical School, Boston, MA 02115, USA.,Alzheimer's Disease Research Laboratory, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Casey A Maguire
- Molecular Neurogenetics Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129.,Harvard Medical School, Boston, MA 02115, USA
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16
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Eftekharzadeh B, Daigle JG, Kapinos LE, Coyne A, Schiantarelli J, Carlomagno Y, Cook C, Miller SJ, Dujardin S, Amaral AS, Grima JC, Bennett RE, Tepper K, DeTure M, Vanderburg CR, Corjuc BT, DeVos SL, Gonzalez JA, Chew J, Vidensky S, Gage FH, Mertens J, Troncoso J, Mandelkow E, Salvatella X, Lim RYH, Petrucelli L, Wegmann S, Rothstein JD, Hyman BT. Tau Protein Disrupts Nucleocytoplasmic Transport in Alzheimer's Disease. Neuron 2019; 99:925-940.e7. [PMID: 30189209 DOI: 10.1016/j.neuron.2018.07.039] [Citation(s) in RCA: 244] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 05/14/2018] [Accepted: 07/20/2018] [Indexed: 10/28/2022]
Abstract
Tau is the major constituent of neurofibrillary tangles in Alzheimer's disease (AD), but the mechanism underlying tau-associated neural damage remains unclear. Here, we show that tau can directly interact with nucleoporins of the nuclear pore complex (NPC) and affect their structural and functional integrity. Pathological tau impairs nuclear import and export in tau-overexpressing transgenic mice and in human AD brain tissue. Furthermore, the nucleoporin Nup98 accumulates in the cell bodies of some tangle-bearing neurons and can facilitate tau aggregation in vitro. These data support the hypothesis that tau can directly interact with NPC components, leading to their mislocalization and consequent disruption of NPC function. This raises the possibility that NPC dysfunction contributes to tau-induced neurotoxicity in AD and tauopathies.
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Affiliation(s)
- Bahareh Eftekharzadeh
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - J Gavin Daigle
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | | | - Alyssa Coyne
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Julia Schiantarelli
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Yari Carlomagno
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Casey Cook
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Sean J Miller
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Simon Dujardin
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Ana S Amaral
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Jonathan C Grima
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Rachel E Bennett
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Katharina Tepper
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Michael DeTure
- Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA
| | - Charles R Vanderburg
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Bianca T Corjuc
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Sarah L DeVos
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Jose Antonio Gonzalez
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Jeannie Chew
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Svetlana Vidensky
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Fred H Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Jerome Mertens
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Juan Troncoso
- Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA
| | - Eckhard Mandelkow
- German Center for Neurodegenerative Diseases (DZNE) and CAESAR Research Center, 53175 Bonn, Germany
| | | | | | | | - Susanne Wegmann
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Jeffrey D Rothstein
- Brain Science Institute, Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA.
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DeVos SL, Corjuc BT, Commins C, Dujardin S, Bannon RN, Corjuc D, Moore BD, Bennett RE, Jorfi M, Gonzales JA, Dooley PM, Roe AD, Pitstick R, Irimia D, Frosch MP, Carlson GA, Hyman BT. Tau reduction in the presence of amyloid-β prevents tau pathology and neuronal death in vivo. Brain 2019; 141:2194-2212. [PMID: 29733334 DOI: 10.1093/brain/awy117] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 03/05/2018] [Indexed: 11/14/2022] Open
Abstract
Several studies have now supported the use of a tau lowering agent as a possible therapy in the treatment of tauopathy disorders, including Alzheimer's disease. In human Alzheimer's disease, however, concurrent amyloid-β deposition appears to synergize and accelerate tau pathological changes. Thus far, tau reduction strategies that have been tested in vivo have been examined in the setting of tau pathology without confounding amyloid-β deposition. To determine whether reducing total human tau expression in a transgenic model where there is concurrent amyloid-β plaque formation can still reduce tau pathology and protect against neuronal loss, we have taken advantage of the regulatable tau transgene in APP/PS1 × rTg4510 mice. These mice develop both neurofibrillary tangles as well as amyloid-β plaques throughout the cortex and hippocampus. By suppressing human tau expression for 6 months in the APP/PS1 × rTg4510 mice using doxycycline, AT8 tau pathology, bioactivity, and astrogliosis were reduced, though importantly to a lesser extent than lowering tau in the rTg4510 alone mice. Based on non-denaturing gels and proteinase K digestions, the remaining tau aggregates in the presence of amyloid-β exhibit a longer-lived aggregate conformation. Nonetheless, lowering the expression of the human tau transgene was sufficient to equally ameliorate thioflavin-S positive tangles and prevent neuronal loss equally well in both the APP/PS1 × rTg4510 mice and the rTg4510 cohort. Together, these results suggest that, although amyloid-β stabilizes tau aggregates, lowering total tau levels is still an effective strategy for the treatment of tau pathology and neuronal loss even in the presence of amyloid-β deposition.
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Affiliation(s)
- Sarah L DeVos
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Bianca T Corjuc
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Caitlin Commins
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Simon Dujardin
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Riley N Bannon
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Diana Corjuc
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Benjamin D Moore
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Rachel E Bennett
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Mehdi Jorfi
- McLaughlin Research Institute, Great Falls, Montana, USA
| | - Jose A Gonzales
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Patrick M Dooley
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Allyson D Roe
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Rose Pitstick
- McLaughlin Research Institute, Great Falls, Montana, USA
| | - Daniel Irimia
- Center for Engineering in Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Matthew P Frosch
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA.,C.S. Kubik Laboratory for Neuropathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - George A Carlson
- Center for Engineering in Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Bradley T Hyman
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
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Wegmann S, Bennett RE, Delorme L, Robbins AB, Hu M, McKenzie D, Kirk MJ, Schiantarelli J, Tunio N, Amaral AC, Fan Z, Nicholls S, Hudry E, Hyman BT. Experimental evidence for the age dependence of tau protein spread in the brain. Sci Adv 2019; 5:eaaw6404. [PMID: 31249873 PMCID: PMC6594764 DOI: 10.1126/sciadv.aaw6404] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 05/16/2019] [Indexed: 05/24/2023]
Abstract
The incidence of Alzheimer's disease (AD), which is characterized by progressive cognitive decline that correlates with the spread of tau protein aggregation in the cortical mantle, is strongly age-related. It could be that age predisposes the brain for tau misfolding and supports the propagation of tau pathology. We tested this hypothesis using an experimental setup that allowed for exploration of age-related factors of tau spread and regional vulnerability. We virally expressed human tau locally in entorhinal cortex (EC) neurons of young or old mice and monitored the cell-to-cell tau protein spread by immunolabeling. Old animals showed more tau spreading in the hippocampus and adjacent cortical areas and accumulated more misfolded tau in EC neurons. No misfolding, at any age, was observed in the striatum, a brain region mostly unaffected by tangles. Age and brain region dependent tau spreading and misfolding likely contribute to the profound age-related risk for sporadic AD.
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Affiliation(s)
- Susanne Wegmann
- German Center for Neurodegenerative Diseases (DZNE), 10117 Berlin, Germany
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Rachel E. Bennett
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Louis Delorme
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ashley B. Robbins
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Miwei Hu
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Danny McKenzie
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Molly J. Kirk
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Nahel Tunio
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ana C. Amaral
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Zhanyun Fan
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Samantha Nicholls
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Eloise Hudry
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Bradley T. Hyman
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Eftekharzadeh B, Daigle JG, Kapinos LE, Coyne A, Schiantarelli J, Carlomagno Y, Cook C, Miller SJ, Dujardin S, Amaral AS, Grima JC, Bennett RE, Tepper K, DeTure M, Vanderburg CR, Corjuc BT, DeVos SL, Gonzalez JA, Chew J, Vidensky S, Gage FH, Mertens J, Troncoso J, Mandelkow E, Salvatella X, Lim RYH, Petrucelli L, Wegmann S, Rothstein JD, Hyman BT. Tau Protein Disrupts Nucleocytoplasmic Transport in Alzheimer's Disease. Neuron 2019; 101:349. [PMID: 30653936 DOI: 10.1016/j.neuron.2018.12.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Bennett RE, Bryant A, Hu M, Robbins AB, Hopp SC, Hyman BT. Partial reduction of microglia does not affect tau pathology in aged mice. J Neuroinflammation 2018; 15:311. [PMID: 30413160 PMCID: PMC6230271 DOI: 10.1186/s12974-018-1348-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 10/26/2018] [Indexed: 12/22/2022] Open
Abstract
Background Activation of inflammation pathways in the brain occurs in Alzheimer’s disease and may contribute to the accumulation and spread of pathological proteins including tau. The goal of this study was to identify how changes in microglia, a key inflammatory cell type, may contribute to tau protein accumulation and pathology-associated changes in immune and non-immune cell processes such as neuronal degeneration, astrocyte physiology, cytokine expression, and blood vessel morphology. Methods We used PLX3397 (290 mg/kg), a colony-stimulating factor receptor 1 (CSF1R) inhibitor, to reduce the number of microglia in the brains of a tau-overexpressing mouse model. Mice were fed PLX3397 in chow or a control diet for 3 months beginning at 12 months of age and then were subsequently analyzed for changes in blood vessel morphology by in vivo two-photon microscopy and tissues were collected for biochemistry and histology. Results PLX3397 reduced microglial numbers by 30% regardless of genotype compared to control diet-treated mice. No change in tau burden, cortical atrophy, blood vessels, or astrocyte activation was detected. All Tg4510 mice were observed to have an increased in “disease-associated” microglial gene expression, but PLX3397 treatment did not reduce expression of these genes. Surprisingly, PLX3397 treatment resulted in upregulation of CD68 and Tgf1β. Conclusions Manipulating microglial activity may not be an effective strategy to combat tau pathological lesions. Higher doses of PLX3397 may be required or earlier intervention in the disease course. Overall, this indicates a need for a better understanding of specific microglial changes and their relation to the disease process.
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Affiliation(s)
- Rachel E Bennett
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Annie Bryant
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Miwei Hu
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Ashley B Robbins
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Sarah C Hopp
- Biggs Institute for Alzheimer's and Neurodegenerative Disease, University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA. .,Department of Pharmacology, University of Texas Health Science Center San Antonio, San Antonio, TX, 78229, USA.
| | - Bradley T Hyman
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
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21
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Wegmann S, Eftekharzadeh B, Tepper K, Zoltowska KM, Bennett RE, Dujardin S, Laskowski PR, MacKenzie D, Kamath T, Commins C, Vanderburg C, Roe AD, Fan Z, Molliex AM, Hernandez-Vega A, Muller D, Hyman AA, Mandelkow E, Taylor JP, Hyman BT. Tau protein liquid-liquid phase separation can initiate tau aggregation. EMBO J 2018; 37:e98049. [PMID: 29472250 PMCID: PMC5881631 DOI: 10.15252/embj.201798049] [Citation(s) in RCA: 584] [Impact Index Per Article: 97.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 01/17/2018] [Accepted: 01/19/2018] [Indexed: 11/13/2022] Open
Abstract
The transition between soluble intrinsically disordered tau protein and aggregated tau in neurofibrillary tangles in Alzheimer's disease is unknown. Here, we propose that soluble tau species can undergo liquid-liquid phase separation (LLPS) under cellular conditions and that phase-separated tau droplets can serve as an intermediate toward tau aggregate formation. We demonstrate that phosphorylated or mutant aggregation prone recombinant tau undergoes LLPS, as does high molecular weight soluble phospho-tau isolated from human Alzheimer brain. Droplet-like tau can also be observed in neurons and other cells. We found that tau droplets become gel-like in minutes, and over days start to spontaneously form thioflavin-S-positive tau aggregates that are competent of seeding cellular tau aggregation. Since analogous LLPS observations have been made for FUS, hnRNPA1, and TDP43, which aggregate in the context of amyotrophic lateral sclerosis, we suggest that LLPS represents a biophysical process with a role in multiple different neurodegenerative diseases.
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Affiliation(s)
- Susanne Wegmann
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Bahareh Eftekharzadeh
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Katharina Tepper
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Katarzyna M Zoltowska
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Rachel E Bennett
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Simon Dujardin
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Pawel R Laskowski
- Department for Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Danny MacKenzie
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Tarun Kamath
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Caitlin Commins
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Charles Vanderburg
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Allyson D Roe
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Zhanyun Fan
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Amandine M Molliex
- Department of Cell & Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | | | - Daniel Muller
- Department for Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Anthony A Hyman
- Department for Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Eckhard Mandelkow
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
- Max-Planck Institute for Metabolism Research, Hamburg Outstation c/o DESY, Hamburg, Germany
- CAESAR Research Center, Bonn, Germany
| | - J Paul Taylor
- Department of Cell & Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
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22
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Wegmann S, Bennett RE, Amaral AS, Hyman BT. Studying tau protein propagation and pathology in the mouse brain using adeno-associated viruses. Methods Cell Biol 2017; 141:307-322. [PMID: 28882310 DOI: 10.1016/bs.mcb.2017.06.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The progressive spread of pathological brain lesions containing aggregated tau protein is a hallmark of Alzheimer's disease and other neurodegenerative diseases. In AD, this process follows a distinct pattern along neuronal connections from the entorhinal cortex to hippocampal areas and further on through the limbic system. In other tauopathies, the spread of tau appears less hierarchical throughout the brain, and also nonpathological tau is reported to cross-synaptic connections in the brain. To be able to study the process of cell-to-cell transport of tau and the associated neurotoxicity in the brain in vivo, adeno-associated virus-mediated expression of tau can be used to express different forms of tau in distinct brain areas in rodent models. As an example, we describe how the expression of FTD-mutant human tauP301L in the entorhinal cortex of wild-type mice can be used to study the propagation of tau to connected neurons and to determine pathological consequences such as tau hyperphosphorylation, misfolding, and gliosis. The approach described can easily be translated to study other aggregating and/or propagating proteins in the brain such as synuclein, Abeta, or SOD1.
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Affiliation(s)
- Susanne Wegmann
- Massachusetts General Hospital, Harvard Medical School, Mass. Institute for Neurodegenerative Diseases (MIND), Boston, MA, United States.
| | - Rachel E Bennett
- Massachusetts General Hospital, Harvard Medical School, Mass. Institute for Neurodegenerative Diseases (MIND), Boston, MA, United States
| | - Ana S Amaral
- Massachusetts General Hospital, Harvard Medical School, Mass. Institute for Neurodegenerative Diseases (MIND), Boston, MA, United States
| | - Bradley T Hyman
- Massachusetts General Hospital, Harvard Medical School, Mass. Institute for Neurodegenerative Diseases (MIND), Boston, MA, United States
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23
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Nicholls SB, DeVos SL, Commins C, Nobuhara C, Bennett RE, Corjuc DL, Maury E, Eftekharzadeh B, Akingbade O, Fan Z, Roe AD, Takeda S, Wegmann S, Hyman BT. Characterization of TauC3 antibody and demonstration of its potential to block tau propagation. PLoS One 2017; 12:e0177914. [PMID: 28531180 PMCID: PMC5439699 DOI: 10.1371/journal.pone.0177914] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 05/05/2017] [Indexed: 11/21/2022] Open
Abstract
The spread of neurofibrillary tangle (NFT) pathology through the human brain is a hallmark of Alzheimer’s disease (AD), which is thought to be caused by the propagation of “seeding” competent soluble misfolded tau. “TauC3”, a C-terminally truncated form of tau that is generated by caspase-3 cleavage at D421, has previously been observed in NFTs and has been implicated in tau toxicity. Here we show that TauC3 is found in the seeding competent high molecular weight (HMW) protein fraction of human AD brain. Using a specific TauC3 antibody, we were able to substantially block the HMW tau seeding activity of human AD brain extracts in an in vitro tau seeding FRET assay. We propose that TauC3 could contribute to the templated tau misfolding that leads to NFT spread in AD brains.
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Affiliation(s)
- Samantha B. Nicholls
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Sarah L. DeVos
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Caitlin Commins
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Chloe Nobuhara
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Rachel E. Bennett
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Diana L. Corjuc
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Eduardo Maury
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Bahareh Eftekharzadeh
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Ololade Akingbade
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Zhanyun Fan
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Allyson D. Roe
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Shuko Takeda
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Susanne Wegmann
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
| | - Bradley T. Hyman
- Massachusetts General Hospital, Harvard Medical School, Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Charlestown, Massachusetts, United States of America
- * E-mail:
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Bennett RE, DeVos SL, Dujardin S, Corjuc B, Gor R, Gonzalez J, Roe AD, Frosch MP, Pitstick R, Carlson GA, Hyman BT. Enhanced Tau Aggregation in the Presence of Amyloid β. Am J Pathol 2017; 187:1601-1612. [PMID: 28500862 DOI: 10.1016/j.ajpath.2017.03.011] [Citation(s) in RCA: 144] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 03/01/2017] [Accepted: 03/22/2017] [Indexed: 01/12/2023]
Abstract
Amyloid plaques and neurofibrillary tangles co-occur in Alzheimer disease, but with different topological and temporal patterns. Whether these two lesions are independent or pathobiologically related is uncertain. For example, amyloid deposition in the neocortex precedes the spread of tau neurofibrillary tangles from the limbic areas to the cortex. We examined the aggregation properties of tau isolated from human cases with early tau pathology (Braak II) with and without plaques. Using a well-established HEK cell biosensor assay, we show that tau from cases with plaques has an enhanced ability to induce tau aggregates compared to tau from cases without plaques. To further explore this effect, we combined mice carrying the APP/PS1 transgene array that develop plaques with rTg4510 mice carrying the P301L mutant human tau transgene that develop extensive tau pathology with age. The resulting APP/PS1-rTg4510 mice had a threefold increase in tau seeding activity over the rTg4510 strain, without change in tau production or extracellular release. Surprisingly, this effect was observed before overt amyloid deposition. The enhancement of tau aggregation was also apparent by an increase in histological measures of tau pathology in young APP/PS1-rTg4510 mice and an increase in high-molecular-weight tau. Overall, these data provide evidence that amyloid β acts to enhance tau pathology by increasing the formation of tau species capable of seeding new aggregates.
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Affiliation(s)
- Rachel E Bennett
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Sarah L DeVos
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Simon Dujardin
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Bianca Corjuc
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Rucha Gor
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Jose Gonzalez
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Allyson D Roe
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Matthew P Frosch
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts; C.S. Kubik Laboratory for Neuropathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | | | | | - Bradley T Hyman
- Department of Neurology, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts.
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Zamorski MA, Bennett RE, Boulos D, Garber BG, Jetly R, Sareen J. The 2013 Canadian Forces Mental Health Survey: Background and Methods. Can J Psychiatry 2016; 61:10S-25S. [PMID: 27270738 PMCID: PMC4800478 DOI: 10.1177/0706743716632731] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE The 2013 Canadian Forces Mental Health Survey (CFMHS) collected detailed information on mental health problems, their impacts, occupational and nonoccupational determinants of mental health, and the use of mental health services from a random sample of 8200 serving personnel. The objective of this article is to provide a firm scientific foundation for understanding and interpreting the CFMHS findings. METHODS This narrative review first provides a snapshot of the Canadian Armed Forces (CAF), focusing on 2 key determinants of mental health: the deployment of more than 40,000 personnel in support of the mission in Afghanistan and the extensive renewal of the CAF mental health system. The findings of recent population-based CAF mental health research are reviewed, with a focus on findings from the very similar mental health survey done in 2002. Finally, key aspects of the methods of the 2013 CFMHS are presented. RESULTS The findings of 20 peer-reviewed publications using the 2002 mental health survey data are reviewed, along with those of 25 publications from other major CAF mental health research projects executed over the past decade. CONCLUSIONS More than a decade of population-based mental health research in the CAF has provided a detailed picture of its mental health and use of mental health services. This knowledge base and the homology of the 2013 survey with the 2002 CAF survey and general population surveys in 2002 and 2012 will provide an unusual opportunity to use the CFMHS to situate mental health in the CAF in a historical and societal perspective.
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Affiliation(s)
- Mark A Zamorski
- Directorate of Mental Health, Canadian Forces Health Services Group, Ottawa, Ontario Department of Family Medicine, University of Ottawa, Ottawa, Ontario
| | - Rachel E Bennett
- Directorate of Mental Health, Canadian Forces Health Services Group, Ottawa, Ontario
| | - David Boulos
- Directorate of Mental Health, Canadian Forces Health Services Group, Ottawa, Ontario
| | - Bryan G Garber
- Directorate of Mental Health, Canadian Forces Health Services Group, Ottawa, Ontario
| | - Rakesh Jetly
- Directorate of Mental Health, Canadian Forces Health Services Group, Ottawa, Ontario
| | - Jitender Sareen
- Departments of Psychiatry, Psychology, and Community Health Sciences, University of Manitoba, Winnipeg, Manitoba
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Zamorski MA, Bennett RE, Rusu C, Weeks M, Boulos D, Garber BG. Prevalence of Past-Year Mental Disorders in the Canadian Armed Forces, 2002-2013. Can J Psychiatry 2016; 61:26S-35S. [PMID: 27270739 PMCID: PMC4800474 DOI: 10.1177/0706743716628854] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE More than 40,000 Canadian Armed Forces (CAF) personnel have deployed in support of the mission in Afghanistan since 2002. Over the same period, the CAF strengthened its mental health system. This article explores the effect of these events on the prevalence of past-year mental disorders over the period 2002-2013. METHOD The data sources were 2 highly comparable population-based mental health surveys of CAF Regular Force personnel done in 2002 and 2013 (n = 5155 and 6996, respectively). Data were collected via in-person interviews with Statistics Canada personnel using the World Health Organization's Composite International Diagnostic Interview to assess past-year disorders. RESULTS In 2013, 16.5% had 1 or more of the 6 past-year disorders assessed in the survey, with the most common conditions being major depressive episode (MDE), posttraumatic stress disorder (PTSD), and generalized anxiety disorder (GAD), which affected 8.0%, 5.3%, and 4.7%, respectively. The prevalence of PTSD, GAD, and panic disorder has increased significantly since 2002 (adjusted odds ratios from logistic regression models = 2.1, 3.0, and 1.9, respectively), while no change was seen for MDE. The comorbidity of mood and anxiety disorders increased significantly over time, being seen in 27.4% and 41.0% of those with mental disorders in 2002 and 2013, respectively. CONCLUSION There has been an increase in the prevalence of PTSD and other anxiety disorders and of the extent of comorbidity of mood and anxiety disorders in CAF personnel over the period 2002-2013.
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Affiliation(s)
- Mark A Zamorski
- Directorate of Mental Health, Canadian Forces Health Services Group Headquarters, Ottawa, Ontario Department of Family Medicine, University of Ottawa, Ottawa, Ontario
| | - Rachel E Bennett
- Directorate of Mental Health, Canadian Forces Health Services Group Headquarters, Ottawa, Ontario
| | - Corneliu Rusu
- Directorate of Mental Health, Canadian Forces Health Services Group Headquarters, Ottawa, Ontario
| | - Murray Weeks
- Directorate of Mental Health, Canadian Forces Health Services Group Headquarters, Ottawa, Ontario
| | - David Boulos
- Directorate of Mental Health, Canadian Forces Health Services Group Headquarters, Ottawa, Ontario
| | - Bryan G Garber
- Directorate of Mental Health, Canadian Forces Health Services Group Headquarters, Ottawa, Ontario
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Bennett RE, Brody DL. Array tomography for the detection of non-dilated, injured axons in traumatic brain injury. J Neurosci Methods 2015; 245:25-36. [PMID: 25687633 DOI: 10.1016/j.jneumeth.2015.02.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 02/05/2015] [Accepted: 02/06/2015] [Indexed: 10/24/2022]
Abstract
BACKGROUND Axonal injury is a key feature of several types of brain trauma and neurological disease. However, in mice and humans, many axons are less than 500 nm in diameter which is at or below the resolution of most conventional light microscopic imaging methods. In moderate to severe forms of axon injury, damaged axons become dilated and therefore readily detectible by light microscopy. However, in more subtle forms of injury, the damaged axons may remain undilated and therefore difficult to detect. NEW METHOD Here we present a method for adapting array tomography for the identification and quantification of injured axons. In this technique, ultrathin (∼70 nm) plastic sections of tissue are prepared, labeled with axon injury-relevant antibodies and imaged using conventional epifluorescence. RESULTS To demonstrate the use of array-tomography-based methods, we determined that mice that received two closed-skull concussive traumatic brain injury impacts had significantly increased numbers of non-dilated axons that were immunoreactive for non-phosphorylated neurofilament (SMI-32; a marker of axonal injury), compared to sham mice (1682±628 versus 339±52 per mm(2), p=0.004, one-tailed Mann-Whitney U test). Tubulin loss was not evident (p=0.2063, one-tailed Mann-Whitney U test). Furthermore, mice that were subjected to more severe injury had a loss of tubulin in addition to both dilated and non-dilated SMI-32 immunoreactive axons indicating that this technique is suitable for the analysis of various injury conditions. COMPARISON WITH EXISTING METHOD With array tomography we could detect similar overall numbers of axons as electron microscopy, but accurate diameter measurements were limited to those with diameters >200 nm. Importantly, array tomography had greater sensitivity for detecting small non-dilated injured axons compared with conventional immunohistochemistry. CONCLUSION Imaging of individual axons and quantification of subtle axonal injury is possible using this array tomography method. This method may be most useful for the assessment of concussive injuries and other pathologies in which injured axons are not typically dilated. The ability to process moderately large volumes of tissue, label multiple proteins of interest, and automate analysis support array tomography as a useful alternative to electron microscopy.
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Affiliation(s)
- Rachel E Bennett
- Department of Neurology, Washington University in St. Louis, 660 S. Euclid Avenue, Saint Louis, MO 63110, USA
| | - David L Brody
- Department of Neurology, Washington University in St. Louis, 660 S. Euclid Avenue, Saint Louis, MO 63110, USA.
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Brody DL, Benetatos J, Bennett RE, Klemenhagen KC, Mac Donald CL. The pathophysiology of repetitive concussive traumatic brain injury in experimental models; new developments and open questions. Mol Cell Neurosci 2015; 66:91-8. [PMID: 25684677 DOI: 10.1016/j.mcn.2015.02.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 02/03/2015] [Accepted: 02/06/2015] [Indexed: 12/14/2022] Open
Abstract
In recent years, there has been an increasing interest in the pathophysiology of repetitive concussive traumatic brain injury (rcTBI) in large part due to the association with dramatic cases of progressive neurological deterioration in professional athletes, military personnel, and others. However, our understanding of the pathophysiology of rcTBI is less advanced than for more severe brain injuries. Most prominently, the mechanisms underlying traumatic axonal injury, microglial activation, amyloid-beta accumulation, and progressive tau pathology are not yet known. In addition, the role of injury to dendritic spine cytoskeletal structures, vascular reactivity impairments, and microthrombi are intriguing and subjects of ongoing inquiry. Methods for quantitative analysis of axonal injury, dendritic injury, and synaptic loss need to be refined for the field to move forward in a rigorous fashion. We and others are attempting to develop translational approaches to assess these specific pathophysiological events in both animals and humans to facilitate clinically relevant pharmacodynamic assessments of candidate therapeutics. In this article, we review and discuss several of the recent experimental results from our lab and others. We include new initial data describing the difficulty in modeling progressive tau pathology in experimental rcTBI, and results demonstrating that sertraline can alleviate social interaction deficits and depressive-like behaviors following experimental rcTBI plus foot shock stress. Furthermore, we propose a discrete set of open, experimentally tractable questions that may serve as a framework for future investigations. In addition, we also raise several important questions that are less experimentally tractable at this time, in hopes that they may stimulate future methodological developments to address them. This article is part of a Special Issue entitled "Traumatic Brain Injury".
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Affiliation(s)
- David L Brody
- Department of Neurology, Washington University School of Medicine and Hope Center for Neurological Disorders, St Louis, MO, USA.
| | - Joseph Benetatos
- Department of Neurology, Washington University School of Medicine and Hope Center for Neurological Disorders, St Louis, MO, USA
| | - Rachel E Bennett
- Department of Neurology, Washington University School of Medicine and Hope Center for Neurological Disorders, St Louis, MO, USA
| | - Kristen C Klemenhagen
- Department of Neurology, Washington University School of Medicine and Hope Center for Neurological Disorders, St Louis, MO, USA
| | - Christine L Mac Donald
- Department of Neurology, Washington University School of Medicine and Hope Center for Neurological Disorders, St Louis, MO, USA
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Bennett RE, Brody DL. Acute reduction of microglia does not alter axonal injury in a mouse model of repetitive concussive traumatic brain injury. J Neurotrauma 2014; 31:1647-63. [PMID: 24797413 DOI: 10.1089/neu.2013.3320] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The pathological processes that lead to long-term consequences of multiple concussions are unclear. Primary mechanical damage to axons during concussion is likely to contribute to dysfunction. Secondary damage has been hypothesized to be induced or exacerbated by inflammation. The main inflammatory cells in the brain are microglia, a type of macrophage. This research sought to determine the contribution of microglia to axon degeneration after repetitive closed-skull traumatic brain injury (rcTBI) using CD11b-TK (thymidine kinase) mice, a valganciclovir-inducible model of macrophage depletion. Low-dose (1 mg/mL) valganciclovir was found to reduce the microglial population in the corpus callosum and external capsule by 35% after rcTBI in CD11b-TK mice. At both acute (7 days) and subacute (21 days) time points after rcTBI, reduction of the microglial population did not alter the extent of axon injury as visualized by silver staining. Further reduction of the microglial population by 56%, using an intermediate dose (10 mg/mL), also did not alter the extent of silver staining, amyloid precursor protein accumulation, neurofilament labeling, or axon injury evident by electron microscopy at 7 days postinjury. Longer treatment of CD11b-TK mice with intermediate dose and treatment for 14 days with high-dose (50 mg/mL) valganciclovir were both found to be toxic in this injury model. Altogether, these data are most consistent with the idea that microglia do not contribute to acute axon degeneration after multiple concussive injuries. The possibility of longer-term effects on axon structure or function cannot be ruled out. Nonetheless, alternative strategies directly targeting injury to axons may be a more beneficial approach to concussion treatment than targeting secondary processes of microglial-driven inflammation.
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Affiliation(s)
- Rachel E Bennett
- Department of Neurology, Washington University , St. Louis, Missouri
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Willie JT, Lim MM, Bennett RE, Azarion AA, Schwetye KE, Brody DL. Controlled cortical impact traumatic brain injury acutely disrupts wakefulness and extracellular orexin dynamics as determined by intracerebral microdialysis in mice. J Neurotrauma 2013; 29:1908-21. [PMID: 22607167 DOI: 10.1089/neu.2012.2404] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Among other deficits, traumatic brain injury (TBI) causes impaired arousal and cognitive dysfunction. Hypothalamic orexin neuropeptides (also called hypocretins) regulate levels of arousal, and cerebrospinal fluid orexin levels are reportedly low in TBI patients. We hypothesized that TBI acutely impairs the dynamics of orexin release into brain interstitial fluid, and that these extracellular orexin levels correlate with wakefulness and motor activity. To test this in mice, we combined an electromagnetic controlled cortical impact (CCI) model of experimental TBI with dual intracerebral microdialysis using one catheter in the hypothalamus and one catheter in the hippocampus, plus electroencephalography/electromyography (EEG/EMG), and motor activity monitoring. Baseline data were continuously collected in tethered but relatively freely moving mice for 2 days. Then, ipsilateral CCI or sham surgery was performed, and data collection was continued for 3 additional days. At baseline, extracellular orexin levels in the hypothalamus showed a circadian rhythm, with peak levels during the dark (wake) phase, and a nadir during the light (rest) phase. Following CCI but not sham surgery, orexin levels were depressed in both the hypothalamus and hippocampus, and diurnal fluctuation amplitudes were blunted in the hypothalamus. At baseline, correlations of orexin with wakefulness and motor activity were positive and highly significant. Following CCI but not sham surgery, the mice exhibited reduced wakefulness and motor activity, and correlations between orexin and these measures were diminished. These abnormal orexin dynamics were associated with hypothalamic astrogliosis, but not acute loss of orexin neurons, as assessed by immunohistochemistry 3 days after injury. Future studies involving experimental manipulations of the orexin system will be required to determine its contribution to neurological outcomes following injury.
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Affiliation(s)
- Jon T Willie
- Department of Neurological Surgery, Emory University School of Medicine, Atlanta, GA, USA
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Abstract
An unusual case of perinatal herpes infection presenting with pneumonia and pleural effusions is described.
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Affiliation(s)
- R E Bennett
- Department of Pediatrics, Texas Tech University Health Sciences Center School of Medicine, Odessa 79763, USA.
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Abstract
The OASIS data set provides home care agencies with well-tested items for the collection of patient health status and outcome data. Illustrative examples of some of the OASIS-derived reports that agencies participating in demonstration projects received are presented. By understanding these reports, clinicians can see how the information they collect is presented in reports and can better understand the importance of collecting complete and accurate data.
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Affiliation(s)
- P W Shaughnessy
- Center for Health Services Research, University of Colorado Health Sciences Center, 1355 South Colorado Boulevard, Suite 306, Denver, Colorado 80222, USA
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Abstract
Relatively little is known about the characteristics of inner-city adults who seek assistance from literacy programs. Increased knowledge about this population will enhance the development of more effective programs, as well as policy options. This study describes the characteristics of 280 adults, ages 16 to 63, who came to an adult literacy program that focused on severe reading difficulties. The program, located within a hospital complex in a large, urban area, attracted these individuals through an extensive multimedia outreach effort. Results suggested that the adults who sought help were generally characterized by a vast array of cognitive, academic, and social difficulties. In addition, the extent of these difficulties increased dramatically as literacy level declined. These findings suggest that comprehensive educational, social, and vocational services may be needed to help adults with severe reading difficulties cope with the diverse and severe problems they face.
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Affiliation(s)
- R L Gottesman
- Adult Literacy Program, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York, USA
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Abstract
The role of cell death in involution of lactating breast was investigated in mice and rats by light and electron microscopy. Apoptosis, recognized by sharply demarcated compaction of chromatin against the nuclear envelope and by shrinkage and budding of the whole cell to form membrane-bounded apoptotic bodies, was responsible for major loss of cells in both species. In the mouse, rapid involution during the first 2 days was associated with shedding of large numbers of apoptotic bodies derived from alveolar epithelial cells into alveolar lumens. This was followed by more gradual regression, during which the bodies were mostly phagocytosed by macrophages within the epithelium. In the rat, glandular involution was a more gradual and uniform process, with shedding of apoptotic epithelial cells into alveolar lumens being much less conspicuous. Apoptosis of myoepithelial cells was observed in mice, the resulting apoptotic bodies being phagocytosed by intraepithelial macrophages, but was not detected in rats. Apoptosis of capillary endothelial cells caused rapid regression of the capillary beds in both mice and rats. Intraepithelial macrophages increased in number during involution, developed cytoplasmic lipofuscin pigment, and either remained within the epithelium or migrated to the interstitium and regional nodes. Cell loss by apoptosis has been demonstrated during involution and atrophy of a variety of other glands. It characteristically results in shrinkage of a tissue without disruption of its basic architecture.
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Affiliation(s)
- N I Walker
- Department of Pathology, Princess Alexandra Hospital, Brisbane, Qld., Australia
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Rock DA, Bennett RE, Jirele T. Factor structure of the graduate record examinations general test in handicapped and nonhandicapped groups. J Appl Psychol 1988; 73:383-92. [PMID: 2972676 DOI: 10.1037/0021-9010.73.3.383] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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Walker NI, Bennett RE, Axelsen RA. Melanosis coli. A consequence of anthraquinone-induced apoptosis of colonic epithelial cells. Am J Pathol 1988; 131:465-76. [PMID: 3381879 PMCID: PMC1880689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A condition closely resembling human melanosis coli was induced in the guinea pig large intestine by daily oral administration of the anthraquinone danthron. Each treatment caused a transient, dose-related wave of apoptosis of the colonic surface epithelial cells. Most of the resulting apoptotic bodies were phagocytosed by intraepithelial macrophages and carried by them through fenestrae in the epithelial basement membrane to the lamina propria. Here, the apoptotic bodies were transformed into typical lipofuscin pigment in macrophage heterolysosomes. Continued danthron administration caused progressive accumulation of pigmented macrophages in the bowel wall, whereas ongoing migration of pigmented macrophages to regional lymph nodes resulted, after danthron was ceased, in sequential loss of the pigmented cells from the superficial and deep lamina propria. Examination of colonic biopsies from patients with melanosis coli shows increased numbers of apoptotic bodies in the surface epithelium and lamina propria, suggesting implication of the same cellular processes in the formation of the pigment in man.
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Affiliation(s)
- N I Walker
- Department of Pathology, University of Queensland, Herston, Australia
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37
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Roth SH, Bennett RE. Nonsteroidal anti-inflammatory drug gastropathy. Recognition and response. Arch Intern Med 1987; 147:2093-100. [PMID: 3318750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Gastropathy, recognized as gastric lesional disease ranging from erosions to actual ulcer craters, represents the most ubiquitous significant complication of common nonsteroidal anti-inflammatory drug (salicylate and nonsalicylate) use. Recently, this association has been established as distinct from classic peptic ulcer disease, which is primarily acid-mediated, duodenal, and more prevalent in a younger, often male, population. Nonsteroidal anti-inflammatory drug gastropathy is usually antral/prepyloric disease, and research indicates it is mediated through blockade of cyclooxygenase with reduction in cytoprotective gastric prostaglandins. The previous literature has been confounded with short-term studies on healthy volunteers and animals that emphasize the resiliency of normal gastric adaptation to heal such gastropathy. Newer long-term studies in patients with arthritis undergoing anti-inflammatory therapy on a sustained basis indicate fatigue of normal adaptation, with persisting gastropathy leading to bleeding and even death. In addition, silent lesions are more common as symptomatology is not synchronous with lesional disease. Since endoscopy is an expensive, not always utilized procedure, it is important to identify the population most at risk for appropriate cytoprotective management as well as modification of the anti-inflammatory therapy program.
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Affiliation(s)
- S H Roth
- Arthritis Center Ltd/Arizona Institute, Phoenix 85012
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Roth SH, Bennett RE, Mitchell CS, Hartman RJ. Cimetidine therapy in nonsteroidal anti-inflammatory drug gastropathy. Double-blind long-term evaluation. Arch Intern Med 1987; 147:1798-801. [PMID: 3310942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
To assess the efficacy of cimetidine in treating and preventing gastric mucosal lesions associated with nonsteroidal anti-inflammatory drug (NSAID) therapy (NSAID gastropathy), we endoscopically studied 104 patients taking NSAIDs for a variety of rheumatic diseases. Fifty-six percent (22/43) of patients randomized to cimetidine 300 mg four times a day and 52% (22/42) of those randomized to placebo showed progression of endoscopic lesions during the eight-week short-term phase. Thirty-nine patients whose endoscopic lesions improved were then randomized to a ten-month maintenance regimen of either cimetidine 400 mg at bedtime or placebo. Fifty percent (7/14) of placebo-treated and 42% (5/12) of cimetidine-treated patients showed progression of lesions during the maintenance phase. The failure of cimetidine to offer any significant benefit under these protocol conditions reflects the fundamental difference in pathophysiologic features between classic acid-mediated ulcer disease and NSAID gastropathy.
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Affiliation(s)
- S H Roth
- Arthritis Center Ltd, Arizona Institutes, Phoenix 85012
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Bennett RE, Calabrese LH, Lucas FV, Clough JD. The association of lupus anticoagulant and anti-DNA binding in patients with systemic lupus erythematosus. Cleve Clin Q 1985; 52:115-8. [PMID: 3928199 DOI: 10.3949/ccjm.52.2.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Bennett RE, Harrison MW, Bishop CJ, Searle J, Kerr JF. The role of apoptosis in atrophy of the small gut mucosa produced by repeated administration of cytosine arabinoside. J Pathol 1984; 142:259-63. [PMID: 6716211 DOI: 10.1002/path.1711420404] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Progressive atrophy of ileal crypts and villi following daily administration of cytosine arabinoside to mice was found to be the result of suppression of mitosis and marked enhancement of apoptosis in the crypt epithelium. The amount of apoptosis produced by each dose decreased as the atrophy advanced. Mucosal regeneration after cessation of administration of the drug was due to increased mitosis in the crypts, and was associated with complete restoration of susceptibility of the crypt cells to further doses. During early regeneration, the wave of increased mitosis was accompanied by a wave of mildly increased apoptosis.
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Abstract
As a result of state and federal education requirements, administrators must collect prodigious amounts of information on exceptional pupils and special education programs. Automated information management systems are thought to provide numerous advantages for administrators overloaded by paperwork. The lure of these benefits has caused many special educators to rush headlong to automate the information-management function. Technologically inexperienced administrators, however, have been surprised to find their overly optimistic expectations severely challenged by the realities of automated systems. This paper describes three real advantages and five common misconceptions brought to automating special education information management.
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Abstract
Microcomputers are currently being used to make technological improvements that affect many areas of our lives. Microcomputer technology is used in the latest cars for regulating fuel flow, in television sets for tuning, in microwave ovens for remembering and acting on cooking instructions, and even in Broadway shows for coordinating complex audiovisual effects. Given this profusion of microcomputer technology in everyday life, it is only natural and appropriate that microcomputers be used to improve the educational process. This article describes some of the ways in which microcomputer and related technologies are being applied to special education. In particular, applications designed to improve special education administration, assessment, instruction, related services, and staff development are discussed.
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Abstract
Informal assessment can make a valuable contribution to the assessment process in special education. Informal procedures are characterized by their ability to be tailored to the needs of specific assessment situations and are especially useful in student evaluation for this reason. However, because informal procedures are typically of unknown technical adequacy they must be constructed and used with care. Specific cautions to be exercised in the construction and use of informal procedures are suggested as one means of increasing the technical quality and utility of these evaluation tools.
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Toliver WH, Bennett RE, Roach CG. Analytical gas desorption apparatus. AMRL-TR-65-61. AMRL TR 1966:1-10. [PMID: 4381816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abstract
The penicillin acylase activity of Penicillium chrysogenum was studied. Washed mycelial suspensions of a high penicillin-producing and a nonproducing strain were found to be similar in respect to relative acylase activity on benzylpenicillin, 2-pentenylpenicillin, heptylpenicillin, and phenoxymethylpenicillin. The relative rates for both strains, as determined by 6-aminopenicillanic acid formation, were approximately 1.0, 2.5, 3.5, and 6.0 on the penicillins in the order given. The high producing strain formed both 6-aminopenicillanic acid and "natural" penicillins in fermentations to which no side-chain precursor had been added. Therefore, its demonstrated ability to cleave the natural penicillins, 2-pentenylpenicillin and heptylpenicillin, suggests that at least some of the 6-aminopenicillanic acid produced during such fermentations arises from the hydrolysis of the natural penicillins. At pH 8.5, the mycelial acylase activity of the nonproducing strain was about three times that at pH 6.0; at 35 C, it was about 1.5 times as active as it was at 30 C. When tested on penicillin G or V, no differences in either total or specific penicillin acylase activity were observed among mycelia harvested from cultures of the nonproducer to which penicillin G, penicillin V, or no penicillin had been added. Acetone-dried mycelium from both strains displayed acylase activity, but considerably less than that shown by viable mycelium. Culture filtrates were essentially inactive, although a very low order of activity was detected when culture filtrate from the nonproducer was treated with acetone and the acetone-precipitated material was assayed in a minimal amount of buffer.
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Bennett RE, Gordon SA, Wildman SG. A LIGHT-TIGHT BOX FOR MAKING SHADOWGRAPHS OF AVENA SEEDLINGS FOR GROWTH HORMONE DETERMINATIONS. Plant Physiol 1943; 18:134-5. [PMID: 16653826 PMCID: PMC438088 DOI: 10.1104/pp.18.1.134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
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