1
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Petralla S, Panayotova M, Franchina E, Fricker G, Puris E. Low-Density Lipoprotein Receptor-Related Protein 1 as a Potential Therapeutic Target in Alzheimer's Disease. Pharmaceutics 2024; 16:948. [PMID: 39065645 PMCID: PMC11279518 DOI: 10.3390/pharmaceutics16070948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Revised: 07/15/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease impacting the lives of millions of people worldwide. The formation of amyloid β (Aβ) plagues in the brain is the main pathological hallmark of AD. The Aβ deposits are formed due to the imbalance between the production and Aβ clearance in the brain and across the blood-brain barrier (BBB). In this respect, low-density lipoprotein receptor-related protein 1 (LRP1) plays a significant role by mediating both brain Aβ production and clearance. Due to its important role in AD pathogenesis, LRP1 is considered an attractive drug target for AD therapies. In the present review, we summarize the current knowledge about the role of LRP1 in AD pathogenesis as well as recent findings on changes in LRP1 expression and function in AD. Finally, we discuss the advances in utilizing LRP1 as a drug target for AD treatments as well as future perspectives on LRP1 research.
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Affiliation(s)
| | | | | | | | - Elena Puris
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany; (S.P.); (M.P.); (E.F.); (G.F.)
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2
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Loeffler DA. Approaches for Increasing Cerebral Efflux of Amyloid-β in Experimental Systems. J Alzheimers Dis 2024; 100:379-411. [PMID: 38875041 PMCID: PMC11307100 DOI: 10.3233/jad-240212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2024] [Indexed: 06/16/2024]
Abstract
Amyloid protein-β (Aβ) concentrations are increased in the brain in both early onset and late onset Alzheimer's disease (AD). In early onset AD, cerebral Aβ production is increased and its clearance is decreased, while increased Aβ burden in late onset AD is due to impaired clearance. Aβ has been the focus of AD therapeutics since development of the amyloid hypothesis, but efforts to slow AD progression by lowering brain Aβ failed until phase 3 trials with the monoclonal antibodies lecanemab and donanemab. In addition to promoting phagocytic clearance of Aβ, antibodies lower cerebral Aβ by efflux of Aβ-antibody complexes across the capillary endothelia, dissolving Aβ aggregates, and a "peripheral sink" mechanism. Although the blood-brain barrier is the main route by which soluble Aβ leaves the brain (facilitated by low-density lipoprotein receptor-related protein-1 and ATP-binding cassette sub-family B member 1), Aβ can also be removed via the blood-cerebrospinal fluid barrier, glymphatic drainage, and intramural periarterial drainage. This review discusses experimental approaches to increase cerebral Aβ efflux via these mechanisms, clinical applications of these approaches, and findings in clinical trials with these approaches in patients with AD or mild cognitive impairment. Based on negative findings in clinical trials with previous approaches targeting monomeric Aβ, increasing the cerebral efflux of soluble Aβ is unlikely to slow AD progression if used as monotherapy. But if used as an adjunct to treatment with lecanemab or donanemab, this approach might allow greater slowing of AD progression than treatment with either antibody alone.
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Affiliation(s)
- David A. Loeffler
- Department of Neurology, Beaumont Research Institute, Corewell Health, Royal Oak, MI, USA
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3
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Ullah R, Lee EJ. Advances in Amyloid-β Clearance in the Brain and Periphery: Implications for Neurodegenerative Diseases. Exp Neurobiol 2023; 32:216-246. [PMID: 37749925 PMCID: PMC10569141 DOI: 10.5607/en23014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/25/2023] [Accepted: 08/23/2023] [Indexed: 09/27/2023] Open
Abstract
This review examines the role of impaired amyloid-β clearance in the accumulation of amyloid-β in the brain and the periphery, which is closely associated with Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA). The molecular mechanism underlying amyloid-β accumulation is largely unknown, but recent evidence suggests that impaired amyloid-β clearance plays a critical role in its accumulation. The review provides an overview of recent research and proposes strategies for efficient amyloid-β clearance in both the brain and periphery. The clearance of amyloid-β can occur through enzymatic or non-enzymatic pathways in the brain, including neuronal and glial cells, blood-brain barrier, interstitial fluid bulk flow, perivascular drainage, and cerebrospinal fluid absorption-mediated pathways. In the periphery, various mechanisms, including peripheral organs, immunomodulation/immune cells, enzymes, amyloid-β-binding proteins, and amyloid-β-binding cells, are involved in amyloid-β clearance. Although recent findings have shed light on amyloid-β clearance in both regions, opportunities remain in areas where limited data is available. Therefore, future strategies that enhance amyloid-β clearance in the brain and/or periphery, either through central or peripheral clearance approaches or in combination, are highly encouraged. These strategies will provide new insight into the disease pathogenesis at the molecular level and explore new targets for inhibiting amyloid-β deposition, which is central to the pathogenesis of sporadic AD (amyloid-β in parenchyma) and CAA (amyloid-β in blood vessels).
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Affiliation(s)
- Rahat Ullah
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, School of Medicine, The Johns Hopkins University, Baltimore, MD 21205, USA
- Department of Neurology, School of Medicine, The Johns Hopkins University, Baltimore, MD 21205, USA
| | - Eun Jeong Lee
- Department of Brain Science, Ajou University School of Medicine, Suwon 16499, Korea
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4
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Loeffler DA. Antibody-Mediated Clearance of Brain Amyloid-β: Mechanisms of Action, Effects of Natural and Monoclonal Anti-Aβ Antibodies, and Downstream Effects. J Alzheimers Dis Rep 2023; 7:873-899. [PMID: 37662616 PMCID: PMC10473157 DOI: 10.3233/adr-230025] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/05/2023] [Indexed: 09/05/2023] Open
Abstract
Immunotherapeutic efforts to slow the clinical progression of Alzheimer's disease (AD) by lowering brain amyloid-β (Aβ) have included Aβ vaccination, intravenous immunoglobulin (IVIG) products, and anti-Aβ monoclonal antibodies. Neither Aβ vaccination nor IVIG slowed disease progression. Despite conflicting phase III results, the monoclonal antibody Aducanumab received Food and Drug Administration (FDA) approval for treatment of AD in June 2021. The only treatments unequivocally demonstrated to slow AD progression to date are the monoclonal antibodies Lecanemab and Donanemab. Lecanemab received FDA approval in January 2023 based on phase II results showing lowering of PET-detectable Aβ; phase III results released at that time indicated slowing of disease progression. Topline results released in May 2023 for Donanemab's phase III trial revealed that primary and secondary end points had been met. Antibody binding to Aβ facilitates its clearance from the brain via multiple mechanisms including promoting its microglial phagocytosis, activating complement, dissolving fibrillar Aβ, and binding of antibody-Aβ complexes to blood-brain barrier receptors. Antibody binding to Aβ in peripheral blood may also promote cerebral efflux of Aβ by a peripheral sink mechanism. According to the amyloid hypothesis, for Aβ targeting to slow AD progression, it must decrease downstream neuropathological processes including tau aggregation and phosphorylation and (possibly) inflammation and oxidative stress. This review discusses antibody-mediated mechanisms of Aβ clearance, findings in AD trials involving Aβ vaccination, IVIG, and anti-Aβ monoclonal antibodies, downstream effects reported in those trials, and approaches which might improve the Aβ-clearing ability of monoclonal antibodies.
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Affiliation(s)
- David A. Loeffler
- Beaumont Research Institute, Department of Neurology, Corewell Health, Royal Oak, MI, USA
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5
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Rué L, Jaspers T, Degors IMS, Noppen S, Schols D, De Strooper B, Dewilde M. Novel Human/Non-Human Primate Cross-Reactive Anti-Transferrin Receptor Nanobodies for Brain Delivery of Biologics. Pharmaceutics 2023; 15:1748. [PMID: 37376196 DOI: 10.3390/pharmaceutics15061748] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
The blood-brain barrier (BBB), while being the gatekeeper of the central nervous system (CNS), is a bottleneck for the treatment of neurological diseases. Unfortunately, most of the biologicals do not reach their brain targets in sufficient quantities. The antibody targeting of receptor-mediated transcytosis (RMT) receptors is an exploited mechanism that increases brain permeability. We previously discovered an anti-human transferrin receptor (TfR) nanobody that could efficiently deliver a therapeutic moiety across the BBB. Despite the high homology between human and cynomolgus TfR, the nanobody was unable to bind the non-human primate receptor. Here we report the discovery of two nanobodies that were able to bind human and cynomolgus TfR, making these nanobodies more clinically relevant. Whereas nanobody BBB00515 bound cynomolgus TfR with 18 times more affinity than it did human TfR, nanobody BBB00533 bound human and cynomolgus TfR with similar affinities. When fused with an anti-beta-site amyloid precursor protein cleaving enzyme (BACE1) antibody (1A11AM), each of the nanobodies was able to increase its brain permeability after peripheral injection. A 40% reduction of brain Aβ1-40 levels could be observed in mice injected with anti-TfR/BACE1 bispecific antibodies when compared to vehicle-injected mice. In summary, we found two nanobodies that could bind both human and cynomolgus TfR with the potential to be used clinically to increase the brain permeability of therapeutic biologicals.
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Affiliation(s)
- Laura Rué
- Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium
- Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000 Leuven, Belgium
| | - Tom Jaspers
- Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Isabelle M S Degors
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium
- Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000 Leuven, Belgium
| | - Sam Noppen
- Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, 3000 Leuven, Belgium
| | - Dominique Schols
- Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, 3000 Leuven, Belgium
| | - Bart De Strooper
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium
- Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000 Leuven, Belgium
- UK Dementia Research Institute, University College London, London WC1E 6BT, UK
| | - Maarten Dewilde
- Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
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6
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Chandrashekar DV, Steinberg RA, Han D, Sumbria RK. Alcohol as a Modifiable Risk Factor for Alzheimer's Disease-Evidence from Experimental Studies. Int J Mol Sci 2023; 24:9492. [PMID: 37298443 PMCID: PMC10253673 DOI: 10.3390/ijms24119492] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/16/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive impairment and memory loss. Epidemiological evidence suggests that heavy alcohol consumption aggravates AD pathology, whereas low alcohol intake may be protective. However, these observations have been inconsistent, and because of methodological discrepancies, the findings remain controversial. Alcohol-feeding studies in AD mice support the notion that high alcohol intake promotes AD, while also hinting that low alcohol doses may be protective against AD. Chronic alcohol feeding to AD mice that delivers alcohol doses sufficient to cause liver injury largely promotes and accelerates AD pathology. The mechanisms by which alcohol can modulate cerebral AD pathology include Toll-like receptors, protein kinase-B (Akt)/mammalian target of rapamycin (mTOR) pathway, cyclic adenosine monophosphate (cAMP) response element-binding protein phosphorylation pathway, glycogen synthase kinase 3-β, cyclin-dependent kinase-5, insulin-like growth factor type-1 receptor, modulation of β-amyloid (Aβ) synthesis and clearance, microglial mediated, and brain endothelial alterations. Besides these brain-centric pathways, alcohol-mediated liver injury may significantly affect brain Aβ levels through alterations in the peripheral-to-central Aβ homeostasis. This article reviews published experimental studies (cell culture and AD rodent models) to summarize the scientific evidence and probable mechanisms (both cerebral and hepatic) by which alcohol promotes or protects against AD progression.
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Affiliation(s)
- Devaraj V. Chandrashekar
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA;
| | - Ross A. Steinberg
- School of Pharmacy and Health Sciences, Keck Graduate Institute, Claremont, CA 91711, USA; (R.A.S.); (D.H.)
| | - Derick Han
- School of Pharmacy and Health Sciences, Keck Graduate Institute, Claremont, CA 91711, USA; (R.A.S.); (D.H.)
| | - Rachita K. Sumbria
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA 92618, USA;
- Department of Neurology, University of California, Irvine, CA 92697, USA
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7
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Ulku I, Liebsch F, Akerman SC, Schulz JF, Kulic L, Hock C, Pietrzik C, Di Spiezio A, Thinakaran G, Saftig P, Multhaup G. Mechanisms of amyloid-β34 generation indicate a pivotal role for BACE1 in amyloid homeostasis. Sci Rep 2023; 13:2216. [PMID: 36750595 PMCID: PMC9905473 DOI: 10.1038/s41598-023-28846-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/25/2023] [Indexed: 02/09/2023] Open
Abstract
The beta‑site amyloid precursor protein (APP) cleaving enzyme (BACE1) was discovered due to its "amyloidogenic" activity which contributes to the production of amyloid-beta (Aβ) peptides. However, BACE1 also possesses an "amyloidolytic" activity, whereby it degrades longer Aβ peptides into a non‑toxic Aβ34 intermediate. Here, we examine conditions that shift the equilibrium between BACE1 amyloidogenic and amyloidolytic activities by altering BACE1/APP ratios. In Alzheimer disease brain tissue, we found an association between elevated levels of BACE1 and Aβ34. In mice, the deletion of one BACE1 gene copy reduced BACE1 amyloidolytic activity by ~ 50%. In cells, a stepwise increase of BACE1 but not APP expression promoted amyloidolytic cleavage resulting in dose-dependently increased Aβ34 levels. At the cellular level, a mislocalization of surplus BACE1 caused a reduction in Aβ34 levels. To align the role of γ-secretase in this pathway, we silenced Presenilin (PS) expression and identified PS2-γ-secretase as the main γ-secretase that generates Aβ40 and Aβ42 peptides serving as substrates for BACE1's amyloidolytic cleavage to generate Aβ34.
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Affiliation(s)
- Irem Ulku
- Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 0B1, Canada
| | - Filip Liebsch
- Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 0B1, Canada.,Department of Chemistry, Institute of Biochemistry, University of Cologne, 50674, Cologne, Germany
| | - S Can Akerman
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Jana F Schulz
- Institut Für Chemie Und Biochemie, Freie Universität Berlin, 14195, Berlin, Germany.,Cardiovascular and Metabolic Sciences, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), 13125, Berlin, Germany
| | - Luka Kulic
- Roche Pharma Research & Early Development, F.Hoffmann-La Roche Ltd., 4070, Basel, Switzerland
| | - Christoph Hock
- Institute for Regenerative Medicine, Un Iversity of Zurich, 8952, Schlieren, Switzerland.,Neurimmune AG, 8952, Schlieren, Switzerland
| | - Claus Pietrzik
- Department Molecular Neurodegeneration, Institute of Pathobiochemistry, University Medical Center of the Johannes Gutenberg-University of Mainz, Duesbergweg 6, 55099, Mainz, Germany
| | | | - Gopal Thinakaran
- Department of Molecular Medicine and Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, 33613, USA
| | - Paul Saftig
- Biochemisches Institut, CAU Kiel, Olshausenstr. 40, 24098, Kiel, Germany
| | - Gerhard Multhaup
- Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 0B1, Canada. .,Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, H3G 1Y6, Canada.
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8
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Oliveira DV, Coupland KG, Shao W, Jin S, Del Gaudio F, Wang S, Fox R, Rutten JW, Sandin J, Zetterberg H, Lundkvist J, Lesnik Oberstein SAJ, Lendahl U, Karlström H. Active immunotherapy reduces NOTCH3 deposition in brain capillaries in a CADASIL mouse model. EMBO Mol Med 2022; 15:e16556. [PMID: 36524456 PMCID: PMC9906330 DOI: 10.15252/emmm.202216556] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/14/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common monogenic form of familial small vessel disease; no preventive or curative therapy is available. CADASIL is caused by mutations in the NOTCH3 gene, resulting in a mutated NOTCH3 receptor, with aggregation of the NOTCH3 extracellular domain (ECD) around vascular smooth muscle cells. In this study, we have developed a novel active immunization therapy specifically targeting CADASIL-like aggregated NOTCH3 ECD. Immunizing CADASIL TgN3R182C150 mice with aggregates composed of CADASIL-R133C mutated and wild-type EGF1-5 repeats for a total of 4 months resulted in a marked reduction (38-48%) in NOTCH3 deposition around brain capillaries, increased microglia activation and lowered serum levels of NOTCH3 ECD. Active immunization did not impact body weight, general behavior, the number and integrity of vascular smooth muscle cells in the retina, neuronal survival, or inflammation or the renal system, suggesting that the therapy is tolerable. This is the first therapeutic study reporting a successful reduction of NOTCH3 accumulation in a CADASIL mouse model supporting further development towards clinical application for the benefit of CADASIL patients.
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Affiliation(s)
- Daniel V Oliveira
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden,Department of Cell Biology, Faculty of ScienceCharles UniversityPragueCzech Republic
| | - Kirsten G Coupland
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Wenchao Shao
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Shaobo Jin
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden,Department of Cell and Molecular BiologyKarolinska InstitutetStockholmSweden
| | | | - Sailan Wang
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Rhys Fox
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden,Department of Cell and Molecular BiologyKarolinska InstitutetStockholmSweden
| | - Julie W Rutten
- Department of Clinical GeneticsLeiden University Medical CenterLeidenThe Netherlands
| | - Johan Sandin
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden,Alzecure FoundationHuddingeSweden,Alzecure PharmaHuddingeSweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgMölndalSweden,Clinical Neurochemistry LaboratorySahlgrenska University HospitalMölndalSweden,Department of Neurodegenerative DiseaseUCL Institute of Neurology, Queen SquareLondonUK,UK Dementia Research Institute at UCLLondonUK,Hong Kong Center for Neurodegenerative Diseases, Clear Water BayHong KongChina
| | - Johan Lundkvist
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden,Alzecure FoundationHuddingeSweden,Sinfonia BiotherapeuticsHuddingeSweden
| | | | - Urban Lendahl
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden,Department of Cell and Molecular BiologyKarolinska InstitutetStockholmSweden
| | - Helena Karlström
- Department of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden
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9
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Wouters Y, Jaspers T, Rué L, Serneels L, De Strooper B, Dewilde M. VHHs as tools for therapeutic protein delivery to the central nervous system. Fluids Barriers CNS 2022; 19:79. [PMID: 36192747 PMCID: PMC9531356 DOI: 10.1186/s12987-022-00374-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 09/07/2022] [Indexed: 11/30/2022] Open
Abstract
Background The blood brain barrier (BBB) limits the therapeutic perspective for central nervous system (CNS) disorders. Previously we found an anti-mouse transferrin receptor (TfR) VHH (Nb62) that was able to deliver a biologically active neuropeptide into the CNS in mice. Here, we aimed to test its potential to shuttle a therapeutic relevant cargo. Since this VHH could not recognize the human TfR and hence its translational potential is limited, we also aimed to find and validate an anti-human transferrin VHH to deliver a therapeutic cargo into the CNS. Methods Alpaca immunizations with human TfR, and subsequent phage selection and screening for human TfR binding VHHs was performed to find a human TfR specific VHH (Nb188). Its ability to cross the BBB was determined by fusing it to neurotensin, a neuropeptide that reduces body temperature when present in the CNS but is not able to cross the BBB on its own. Next, the anti–β-secretase 1 (BACE1) 1A11 Fab and Nb62 or Nb188 were fused to an Fc domain to generate heterodimeric antibodies (1A11AM-Nb62 and 1A11AM-Nb188). These were then administered intravenously in wild-type mice and in mice in which the murine apical domain of the TfR was replaced by the human apical domain (hAPI KI). Pharmacokinetic and pharmacodynamic (PK/PD) studies were performed to assess the concentration of the heterodimeric antibodies in the brain over time and the ability to inhibit brain-specific BACE1 by analysing the brain levels of Aβ1–40. Results Selections and screening of a phage library resulted in the discovery of an anti-human TfR VHH (Nb188). Fusion of Nb188 to neurotensin induced hypothermia after intravenous injections in hAPI KI mice. In addition, systemic administration 1A11AM-Nb62 and 1A11AM-Nb188 fusions were able to reduce Aβ1-40 levels in the brain whereas 1A11AM fused to an irrelevant VHH did not. A PK/PD experiment showed that this effect could last for 3 days. Conclusion We have discovered an anti-human TfR specific VHH that is able to reach the CNS when administered systemically. In addition, both the currently discovered anti-human TfR VHH and the previously identified mouse-specific anti-TfR VHH, are both able to shuttle a therapeutically relevant cargo into the CNS. We suggest the mouse-specific VHH as a valuable research tool in mice and the human-specific VHH as a moiety to enhance the delivery efficiency of therapeutics into the CNS in human patients. Supplementary Information The online version contains supplementary material available at 10.1186/s12987-022-00374-4.
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Affiliation(s)
- Yessica Wouters
- VIB Center for Brain and Disease Research, Campus Gasthuisberg O&N4, Herestraat 49, box 602, 3000, Louvain, Belgium.,Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000, Louvain, Belgium.,Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Tom Jaspers
- VIB Center for Brain and Disease Research, Campus Gasthuisberg O&N4, Herestraat 49, box 602, 3000, Louvain, Belgium.,Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000, Louvain, Belgium.,Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000, Louvain, Belgium
| | - Laura Rué
- VIB Center for Brain and Disease Research, Campus Gasthuisberg O&N4, Herestraat 49, box 602, 3000, Louvain, Belgium.,Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000, Louvain, Belgium
| | - Lutgarde Serneels
- VIB Center for Brain and Disease Research, Campus Gasthuisberg O&N4, Herestraat 49, box 602, 3000, Louvain, Belgium.,Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000, Louvain, Belgium
| | - Bart De Strooper
- VIB Center for Brain and Disease Research, Campus Gasthuisberg O&N4, Herestraat 49, box 602, 3000, Louvain, Belgium. .,Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000, Louvain, Belgium. .,UK Dementia Research Institute, University College London, London, UK.
| | - Maarten Dewilde
- VIB Center for Brain and Disease Research, Campus Gasthuisberg O&N4, Herestraat 49, box 602, 3000, Louvain, Belgium. .,Laboratory for the Research of Neurodegenerative Diseases, Department of Neurosciences, Leuven Brain Institute (LBI), KU Leuven, 3000, Louvain, Belgium. .,Laboratory for Therapeutic and Diagnostic Antibodies, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000, Louvain, Belgium.
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10
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Zieneldien T, Kim J, Sawmiller D, Cao C. The Immune System as a Therapeutic Target for Alzheimer’s Disease. Life (Basel) 2022; 12:life12091440. [PMID: 36143476 PMCID: PMC9506058 DOI: 10.3390/life12091440] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/11/2022] [Accepted: 09/14/2022] [Indexed: 11/25/2022] Open
Abstract
Alzheimer’s disease (AD) is a heterogeneous neurodegenerative disorder and is the most common cause of dementia. Furthermore, aging is considered the most critical risk factor for AD. However, despite the vast amount of research and resources allocated to the understanding and development of AD treatments, setbacks have been more prominent than successes. Recent studies have shown that there is an intricate connection between the immune and central nervous systems, which can be imbalanced and thereby mediate neuroinflammation and AD. Thus, this review examines this connection and how it can be altered with AD. Recent developments in active and passive immunotherapy for AD are also discussed as well as suggestions for improving these therapies moving forward.
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Affiliation(s)
- Tarek Zieneldien
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33612, USA
| | - Janice Kim
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33612, USA
| | - Darrell Sawmiller
- MegaNano BioTech, Inc., 3802 Spectrum Blvd. Suite 122, Tampa, FL 33612, USA
| | - Chuanhai Cao
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33612, USA
- USF-Health Byrd Alzheimer’s Institute, University of South Florida, Tampa, FL 33613, USA
- Correspondence:
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11
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Schreiner TG, Popescu BO. Amyloid Beta Dynamics in Biological Fluids-Therapeutic Impact. J Clin Med 2021; 10:5986. [PMID: 34945282 PMCID: PMC8706225 DOI: 10.3390/jcm10245986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 12/12/2021] [Accepted: 12/16/2021] [Indexed: 12/21/2022] Open
Abstract
Despite the significant impact of Alzheimer's disease (AD) at individual and socioeconomic levels and the numerous research studies carried out on this topic over the last decades, the treatments available in daily clinical practice remain less than satisfactory. Among the accepted etiopathogenic hypotheses, the amyloidogenic pathway theory, although intensively studied and even sometimes controversial, is still providing relevant theoretical elements for understanding the etiology of AD and for the further development of possible therapeutic tools. In this sense, this review aims to offer new insights related to beta amyloid (Aβ), an essential biomarker in AD. First the structure and function of Aβ in normal and pathological conditions are presented in detail, followed by a discussion on the dynamics of Aβ at the level of different biological compartments. There is focus on Aβ elimination modalities at central nervous system (CNS) level, and clearance via the blood-brain barrier seems to play a crucial/dominant role. Finally, different theoretical and already-applied therapeutic approaches for CNS Aβ elimination are presented, including the recent "peripheral sink therapeutic strategy" and "cerebrospinal fluid sinks therapeutic strategy". These data outline the need for a multidisciplinary approach designed to deliver a solution to stimulate Aβ clearance in more direct ways, including from the cerebrospinal fluid level.
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Affiliation(s)
- Thomas Gabriel Schreiner
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 050474 Bucharest, Romania;
- Neurology Department, University of Medicine and Pharmacy “Grigore T. Popa”, 700115 Iași, Romania
- Department of Electrical Measurements and Materials, Faculty of Electrical Engineering and Information Technology, Gheorghe Asachi Technical University of Iasi, 700050 Iasi, Romania
| | - Bogdan Ovidiu Popescu
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 050474 Bucharest, Romania;
- Neurology Department, Colentina Clinical Hospital, 020125 Bucharest, Romania
- Laboratory of Cell Biology, Neurosciences and Experimental Myology, ‘Victor Babes’ National Institute of Pathology, 050096 Bucharest, Romania
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12
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Takata K, Ginhoux F, Shimohama S. Roles of microglia in Alzheimer's disease and impact of new findings on microglial heterogeneity as a target for therapeutic intervention. Biochem Pharmacol 2021; 192:114754. [PMID: 34480881 DOI: 10.1016/j.bcp.2021.114754] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 08/27/2021] [Accepted: 08/30/2021] [Indexed: 12/25/2022]
Abstract
Microglia are specialized macrophages that reside within the central nervous system and play key roles in brain immunity, development and homeostasis. Recent studies also revealed functions of microglia in neuroprotection and neuroinflammation, leading to the discovery that microglia are involved in several brain pathologies including Alzheimer's disease (AD). However, the beneficial and detrimental actions of this intriguing cell population can be challenging to dissect: the advent of single-cell and single-nucleus transcriptomic technologies has revolutionized our understanding of the heterogeneity of multiple cell types and is now being applied to the study of microglia in health and disease. Here, we review recent findings on microglial biology, focusing on insights from single cell transcriptomic studies and the heterogeneity that they reveal, and consider the impact of these findings on our understanding of AD. We also discuss how microglia might represent a next-generation therapeutic target for treatment of AD and other neuroinflammatory conditions.
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Affiliation(s)
- Kazuyuki Takata
- Division of Integrated Pharmaceutical Sciences, Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
| | - Florent Ginhoux
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore 138648, Singapore; Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Translational Immunology Institute, SingHealth/Duke-NUS, Academic Medical Centre, The Academia, Singapore 169856, Singapore
| | - Shun Shimohama
- Department of Neurology, Sapporo Medical University, School of Medicine, Sapporo 060-8543, Japan
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13
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Madrasi K, Das R, Mohmmadabdul H, Lin L, Hyman BT, Lauffenburger DA, Albers MW, Rissman RA, Burke JM, Apgar JF, Wille L, Gruenbaum L, Hua F. Systematic in silico analysis of clinically tested drugs for reducing amyloid-beta plaque accumulation in Alzheimer's disease. Alzheimers Dement 2021; 17:1487-1498. [PMID: 33938131 PMCID: PMC8478725 DOI: 10.1002/alz.12312] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 01/21/2021] [Accepted: 01/21/2021] [Indexed: 01/28/2023]
Abstract
Introduction Despite strong evidence linking amyloid beta (Aβ) to Alzheimer's disease, most clinical trials have shown no clinical efficacy for reasons that remain unclear. To understand why, we developed a quantitative systems pharmacology (QSP) model for seven therapeutics: aducanumab, crenezumab, solanezumab, bapineuzumab, elenbecestat, verubecestat, and semagacestat. Methods Ordinary differential equations were used to model the production, transport, and aggregation of Aβ; pharmacology of the drugs; and their impact on plaque. Results The calibrated model predicts that endogenous plaque turnover is slow, with an estimated half‐life of 2.75 years. This is likely why beta‐secretase inhibitors have a smaller effect on plaque reduction. Of the mechanisms tested, the model predicts binding to plaque and inducing antibody‐dependent cellular phagocytosis is the best approach for plaque reduction. Discussion A QSP model can provide novel insights to clinical results. Our model explains the results of clinical trials and provides guidance for future therapeutic development.
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Affiliation(s)
| | | | | | - Lin Lin
- Applied Biomath, Concord, Massachusetts, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Douglas A Lauffenburger
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Mark W Albers
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Robert A Rissman
- Department of Neurosciences, UCSD School of Medicine, La Jolla, California, USA
| | | | | | - Lucia Wille
- Applied Biomath, Concord, Massachusetts, USA
| | | | - Fei Hua
- Applied Biomath, Concord, Massachusetts, USA
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14
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Bosoi CR, Vandal M, Tournissac M, Leclerc M, Fanet H, Mitchell PL, Verreault M, Trottier J, Virgili J, Tremblay C, Lippman HR, Bajaj JS, Barbier O, Marette A, Calon F. High-Fat Diet Modulates Hepatic Amyloid β and Cerebrosterol Metabolism in the Triple Transgenic Mouse Model of Alzheimer's Disease. Hepatol Commun 2021; 5:446-460. [PMID: 33681678 PMCID: PMC7917280 DOI: 10.1002/hep4.1609] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/09/2020] [Accepted: 08/20/2020] [Indexed: 12/19/2022] Open
Abstract
Obesity and diabetes are strongly associated not only with fatty liver but also cognitive dysfunction. Moreover, their presence, particularly in midlife, is recognized as a risk factor for Alzheimer's disease (AD). AD, the most common cause of dementia, is increasingly considered as a metabolic disease, although underlying pathogenic mechanisms remain unclear. The liver plays a major role in maintaining glucose and lipid homeostasis, as well as in clearing the AD neuropathogenic factor amyloid-β (Aβ) and in metabolizing cerebrosterol, a cerebral-derived oxysterol proposed as an AD biomarker. We hypothesized that liver impairment induced by obesity contributes to AD pathogenesis. We show that the AD triple transgenic mouse model (3xTg-AD) fed a chow diet presents a hepatic phenotype similar to nontransgenic controls (NTg) at 15 months of age. A high-fat diet (HFD), started at the age of 6 months and continued for 9 months, until sacrifice, induced hepatic steatosis in NTg, but not in 3xTg-AD mice, whereas HFD did not induce changes in hepatic fatty acid oxidation, de novo lipogenesis, and gluconeogenesis. HFD-induced obesity was associated with a reduction of insulin-degrading enzyme, one of the main hepatic enzymes responsible for Aβ clearance. The hepatic rate of cerebrosterol glucuronidation was lower in obese 3xTg-AD than in nonobese controls (P < 0.05) and higher compared with obese NTg (P < 0.05), although circulating levels remained unchanged. Conclusion: Modulation of hepatic lipids, Aβ, and cerebrosterol metabolism in obese 3xTg-AD mice differs from control mice. This study sheds light on the liver-brain axis, showing that the chronic presence of NAFLD and changes in liver function affect peripheral AD features and should be considered during development of biomarkers or AD therapeutic targets.
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Affiliation(s)
- Cristina R Bosoi
- Centre De Recherche De L'institut De Cardiologie Et Pneumologie De QuébecQuébecCanada.,Faculté De MédecineUniversité LavalQuébecCanada.,Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada
| | - Milène Vandal
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada.,Faculté De PharmacieUniversité LavalQuébecCanada
| | - Marine Tournissac
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada.,Faculté De PharmacieUniversité LavalQuébecCanada.,OptiNutriBrain International Associated LaboratoryQuébecCanada
| | - Manon Leclerc
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada.,Faculté De PharmacieUniversité LavalQuébecCanada
| | - Hortense Fanet
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada.,Faculté De PharmacieUniversité LavalQuébecCanada.,OptiNutriBrain International Associated LaboratoryQuébecCanada
| | - Patricia L Mitchell
- Centre De Recherche De L'institut De Cardiologie Et Pneumologie De QuébecQuébecCanada
| | - Mélanie Verreault
- Laboratoire de Pharmacologie MoléculaireAxe Endocrinologie et NéphrologieCentre de Recherche du CHU de Québec (Pavillon CHUL)QuébecCanada
| | - Jocelyn Trottier
- Laboratoire de Pharmacologie MoléculaireAxe Endocrinologie et NéphrologieCentre de Recherche du CHU de Québec (Pavillon CHUL)QuébecCanada
| | - Jessica Virgili
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada.,Faculté De PharmacieUniversité LavalQuébecCanada
| | - Cynthia Tremblay
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada
| | - H Robert Lippman
- Central Virginia VA Health Care SystemRichmondVA.,Virginia Commonwealth UniversityRichmondVA
| | - Jasmohan S Bajaj
- Central Virginia VA Health Care SystemRichmondVA.,Virginia Commonwealth UniversityRichmondVA
| | - Olivier Barbier
- Faculté De PharmacieUniversité LavalQuébecCanada.,Laboratoire de Pharmacologie MoléculaireAxe Endocrinologie et NéphrologieCentre de Recherche du CHU de Québec (Pavillon CHUL)QuébecCanada
| | - André Marette
- Centre De Recherche De L'institut De Cardiologie Et Pneumologie De QuébecQuébecCanada.,Faculté De MédecineUniversité LavalQuébecCanada
| | - Frédéric Calon
- Axe NeurosciencesCentre De Recherche du CHU de Québec-Université LavalQuébecCanada.,Faculté De PharmacieUniversité LavalQuébecCanada.,OptiNutriBrain International Associated LaboratoryQuébecCanada
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15
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Vaccination against β-Amyloid as a Strategy for the Prevention of Alzheimer's Disease. BIOLOGY 2020; 9:biology9120425. [PMID: 33260956 PMCID: PMC7761159 DOI: 10.3390/biology9120425] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 12/17/2022]
Abstract
Vaccination relies on the phenomenon of immunity, a long-term change in the immunological response to subsequent encounters with the same pathogen that occurs after the recovery from some infectious diseases. However, vaccination is a strategy that can, in principle, be applied also to non-infectious diseases, such as cancer or neurodegenerative diseases, if an adaptive immune response can prevent the onset of the disease or modify its course. Immunization against β-amyloid has been explored as a vaccination strategy for Alzheimer's disease for over 20 years. No vaccine has been licensed so far, and immunotherapy has come under considerable criticism following the negative results of several phase III clinical trials. In this narrative review, we illustrate the working hypothesis behind immunization against β-amyloid as a vaccination strategy for Alzheimer's disease, and the outcome of the active immunization strategies that have been tested in humans. On the basis of the lessons learned from preclinical and clinical research, we discuss roadblocks and current perspectives in this challenging enterprise in translational immunology.
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16
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Bjorkli C, Sandvig A, Sandvig I. Bridging the Gap Between Fluid Biomarkers for Alzheimer's Disease, Model Systems, and Patients. Front Aging Neurosci 2020; 12:272. [PMID: 32982716 PMCID: PMC7492751 DOI: 10.3389/fnagi.2020.00272] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/06/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD) is a debilitating neurodegenerative disease characterized by the accumulation of two proteins in fibrillar form: amyloid-β (Aβ) and tau. Despite decades of intensive research, we cannot yet pinpoint the exact cause of the disease or unequivocally determine the exact mechanism(s) underlying its progression. This confounds early diagnosis and treatment of the disease. Cerebrospinal fluid (CSF) biomarkers, which can reveal ongoing biochemical changes in the brain, can help monitor developing AD pathology prior to clinical diagnosis. Here we review preclinical and clinical investigations of commonly used biomarkers in animals and patients with AD, which can bridge translation from model systems into the clinic. The core AD biomarkers have been found to translate well across species, whereas biomarkers of neuroinflammation translate to a lesser extent. Nevertheless, there is no absolute equivalence between biomarkers in human AD patients and those examined in preclinical models in terms of revealing key pathological hallmarks of the disease. In this review, we provide an overview of current but also novel AD biomarkers and how they relate to key constituents of the pathological cascade, highlighting confounding factors and pitfalls in interpretation, and also provide recommendations for standardized procedures during sample collection to enhance the translational validity of preclinical AD models.
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Affiliation(s)
- Christiana Bjorkli
- Sandvig Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Axel Sandvig
- Sandvig Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Institute of Neuromedicine and Movement Science, Department of Neurology, St. Olavs Hospital, Trondheim, Norway.,Department of Pharmacology and Clinical Neurosciences, Division of Neuro, Head, and Neck, University Hospital of Umeå, Umeå, Sweden
| | - Ioanna Sandvig
- Sandvig Group, Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
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17
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Rabanel JM, Delbreil P, Banquy X, Brambilla D, Ramassamy C. Periphery-confined particulate systems for the management of neurodegenerative diseases and toxicity: Avoiding the blood-brain-barrier challenge. J Control Release 2020; 322:286-299. [PMID: 32243978 DOI: 10.1016/j.jconrel.2020.03.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 01/07/2023]
Abstract
The blood-brain barrier prevents passage of large and hydrophilic molecules, undermining efforts to deliver most active molecules, proteins and other macromolecules. To date, nanoparticle-assisted delivery has been extensively studied to overcome this challenge but with limited success. On the other hand, for certain brain therapeutic applications, periphery-confined particles could be of immediate therapeutic usefulness. The modulation of CNS dysfunctions from the peripheral compartment is a promising approach, as it does not involve invasive interventions. From recent studies, three main roles could be identified for periphery-confined particles: brain tissue detoxification via the "sink-effect"; a "circulating drug-reservoir" effect to improve drug delivery to brain tissues, and finally, brain vascular endothelium targeting to diagnose or heal vascular-related dysfunctions. These applications are much easier to implement as they do not involve complex therapeutic and targeting strategies and do not require crossing biological barriers. Micro/nano-devices required for such applications will likely be simpler to synthesize and will involve fewer complex materials. Moreover, peripheral particles are expected to be less prone to neurotoxicity and issues related to their diffusion in confined space.
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Affiliation(s)
- Jean-Michel Rabanel
- INRS, Centre Armand-Frappier Santé Biotechnologie, 531 boul. des Prairies, Laval, QC H7V 1B7, Canada
| | - Philippe Delbreil
- Faculty of Pharmacy, Université de Montréal, CP. 6128, succursale Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Xavier Banquy
- Faculty of Pharmacy, Université de Montréal, CP. 6128, succursale Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Davide Brambilla
- Faculty of Pharmacy, Université de Montréal, CP. 6128, succursale Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Charles Ramassamy
- INRS, Centre Armand-Frappier Santé Biotechnologie, 531 boul. des Prairies, Laval, QC H7V 1B7, Canada
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18
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Loeffler DA. AMBAR, an Encouraging Alzheimer's Trial That Raises Questions. Front Neurol 2020; 11:459. [PMID: 32547478 PMCID: PMC7272580 DOI: 10.3389/fneur.2020.00459] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 04/29/2020] [Indexed: 12/18/2022] Open
Abstract
Grifols' recent Alzheimer Management by Albumin Replacement (“AMBAR”) study investigated the effects of plasmapheresis with albumin replacement, plus intravenous immunoglobulin (IVIG) in some subjects, in patients with mild-to-moderate Alzheimer's disease (AD). AMBAR was a phase IIb trial in the United States and a phase III trial in Europe. There were three treatment groups (plasmapheresis with albumin replacement; plasmapheresis with low dose albumin and IVIG; plasmapheresis with high dose albumin and IVIG) and sham-treated controls. Disease progression in pooled treated patients was 66% less than control subjects based on ADAS-Cog scores (p = 0.06) and 52% less based on ADCS-ADL scores (p = 0.03). Moderate AD patients had 61% less progression, based on both ADAS-Cog and ADCS-ADL scores, than their sham-treated counterparts (p-values 0.05 and 0.002), and their CDR-Sb scores declined 53% less than their sham-treated counterparts. However, ADAS-Cog and ADCS-ADL scores were not significantly different between actively-treated and sham-treated mild AD patients, although CDR-Sb scores improved vs. baseline for treated mild AD patients. Patients administered both IVIG and albumin had less reduction in brain glucose metabolism than sham-treated patients. Questions raised by these findings include: what mechanism(s) contributed to slowing of disease progression? Is this approach as effective in mild AD as in moderate AD? Must IVIG be included in the protocol? Does age, sex, or ApoE genotype influence treatment response? Does the protocol increase the risk for amyloid-related imaging abnormalities? How long does disease progression remain slowed post-treatment? A further study should allow this approach to be optimized.
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Affiliation(s)
- David A Loeffler
- Beaumont Research Institute, Department of Neurology, Beaumont Health, Royal Oak, MI, United States
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19
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Wang X, Sun Y, Li T, Cai Y, Han Y. Amyloid-β as a Blood Biomarker for Alzheimer’s Disease: A Review of Recent Literature. J Alzheimers Dis 2020; 73:819-832. [PMID: 31868667 DOI: 10.3233/jad-190714] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Xiaoni Wang
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Yu Sun
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Taoran Li
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Yanning Cai
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Key Laboratory for Neurodegenerative Diseases of the Ministry of Education, Beijing, China
| | - Ying Han
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
- Center of Alzheimer’s Disease, Beijing Institute for Brain Disorders, Beijing, China
- National Clinical Research Center for Geriatric Disorders, Beijing, China
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20
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Transient upregulation of translational efficiency in prodromal and early symptomatic Tg2576 mice contributes to Aβ pathology. Neurobiol Dis 2020; 139:104787. [PMID: 32032729 DOI: 10.1016/j.nbd.2020.104787] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 01/14/2020] [Accepted: 01/31/2020] [Indexed: 12/20/2022] Open
Abstract
TG2576 mice show highest levels of the full length mutant Swedish Human Amyloid Precursor Protein (APPKM670/671LN) during prodromal and early sympotomatic stages. Interestingly, this occurs in association with the unbalanced expression of two of its RNA Binding proteins (RBPs) opposite regulators, the Fragile-X Mental Retardation Protein (FMRP) and the heteronuclear Ribonucleoprotein C (hnRNP C). Whether an augmentation in overall translational efficiency also contributes to the elevation of APP levels at those early developmental stages is currently unknown. We investigated this possibility by performing a longitudinal polyribosome profiling analysis of APP mRNA and protein in total hippocampal extracts from Tg2576 mice. Results showed that protein polysomal signals were exclusively detected in pre-symptomatic (1 months) and early symptomatic (3 months) mutant mice. Differently, hAPP mRNA polysomal signals were detected at any age, but a peak of expression was found when mice were 3-month old. Consistent with an early but transient rise of translational efficiency, the phosphorylated form of the initial translation factor eIF2α (p-eIF2α) was reduced at pre-symptomatic and early symptomatic stages, whereas it was increased at the fully symptomatic stage. Pharmacological downregulation of overall translation in early symptomatic mutants was then found to reduce hippocampal levels of full length APP, Aβspecies, BACE1 and Caspase-3, to rescue predominant LTD at hippocampal synapses, to revert dendritic spine loss and memory alterations, and to reinstate memory-induced c-fosactivation. Altogether, our findings demonstrate that overall translation is upregulated in prodromal and early symptomatic Tg2576 mice, and that restoring proper translational control at the onset of AD-like symptoms blocks the emergence of the AD-like phenotype.
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21
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High Levels of β-Amyloid, Tau, and Phospho-Tau in Red Blood Cells as Biomarkers of Neuropathology in Senescence-Accelerated Mouse. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:5030475. [PMID: 31281579 PMCID: PMC6590616 DOI: 10.1155/2019/5030475] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/25/2019] [Accepted: 05/06/2019] [Indexed: 12/11/2022]
Abstract
Alzheimer's Disease (AD) is the most common Neurodegenerative Disease (ND), primarily characterised by neuroinflammation, neuronal plaques of β-amyloid (Aβ), and neurofibrillary tangles of hyperphosphorylated tau. α-Synuclein (α-syn) and its heteroaggregates with Aβ and tau have been recently included among the neuropathological elements of NDs. These pathological traits are not restricted to the brain, but they reach peripheral fluids as well. In this sense, Red Blood Cells (RBCs) are emerging as a good model to investigate the biochemical alterations of aging and NDs. Herein, the levels of homo- and heteroaggregates of ND-related proteins were analysed at different stages of disease progression. In particular, a validated animal model of AD, the SAMP8 (Senescence-Accelerated Mouse-Prone) and its control strain SAMR1 (Senescence-Accelerated Mouse-Resistant) were used in parallel experiments. The levels of the aforementioned proteins and of the inflammatory marker interleukin-1β (IL-1β) were examined in both brain and RBCs of SAMP8 and SAMR1 at 6 and 8 months. Brain Aβ, tau, and phospho-tau (p-tau) were higher in SAMP8 mice than in control mice and increased with AD progression. Similar accumulation kinetics were found in RBCs, even if slower. By contrast, α-syn and its heterocomplexes (α-syn-Aβ and α-syn-tau) displayed different accumulation kinetics between brain tissue and RBCs. Both brain and peripheral IL-1β levels were higher in SAMP8 mice, but increased sooner in RBCs, suggesting that inflammation might initiate at a peripheral level before affecting the brain. In conclusion, these results confirm RBCs as a valuable model for monitoring neurodegeneration, suggesting peripheral Aβ, tau, and p-tau as potential early biomarkers of AD.
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22
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Liebsch F, Kulic L, Teunissen C, Shobo A, Ulku I, Engelschalt V, Hancock MA, van der Flier WM, Kunach P, Rosa-Neto P, Scheltens P, Poirier J, Saftig P, Bateman RJ, Breitner J, Hock C, Multhaup G. Aβ34 is a BACE1-derived degradation intermediate associated with amyloid clearance and Alzheimer's disease progression. Nat Commun 2019; 10:2240. [PMID: 31110178 PMCID: PMC6527709 DOI: 10.1038/s41467-019-10152-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 04/17/2019] [Indexed: 12/13/2022] Open
Abstract
The beta-site APP cleaving enzyme 1 (BACE1) is known primarily for its initial cleavage of the amyloid precursor protein (APP), which ultimately leads to the generation of Aβ peptides. Here, we provide evidence that altered BACE1 levels and activity impact the degradation of Aβ40 and Aβ42 into a common Aβ34 intermediate. Using human cerebrospinal fluid (CSF) samples from the Amsterdam Dementia Cohort, we show that Aβ34 is elevated in individuals with mild cognitive impairment who later progressed to dementia. Furthermore, Aβ34 levels correlate with the overall Aβ clearance rates in amyloid positive individuals. Using CSF samples from the PREVENT-AD cohort (cognitively normal individuals at risk for Alzheimer’s disease), we further demonstrate that the Aβ34/Aβ42 ratio, representing Aβ degradation and cortical deposition, associates with pre-clinical markers of neurodegeneration. We propose that Aβ34 represents a marker of amyloid clearance and may be helpful for the characterization of Aβ turnover in clinical samples. Aβ34 is generated from degradation of Aβ40 and Aβ42 by β-secretase. Here, the authors show that Aβ34 is a marker for amyloid clearance and is elevated in the CSF of patients that go on to convert from mild cognitive impairment to Alzheimer’s disease, suggesting it may be a useful biomarker.
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Affiliation(s)
- Filip Liebsch
- Department of Pharmacology and Therapeutics and Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Luka Kulic
- Institute for Regenerative Medicine, University of Zurich, CH-8952, Schlieren, Switzerland
| | - Charlotte Teunissen
- Department of Clinical Chemistry, Amsterdam Neuroscience, Amsterdam UMC, Vrije Universiteit Amsterdam, 1081HZ, Amsterdam, The Netherlands
| | - Adeola Shobo
- Department of Pharmacology and Therapeutics and Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Irem Ulku
- Department of Pharmacology and Therapeutics and Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Vivienne Engelschalt
- Institut für Chemie und Biochemie, Freie Universität Berlin, 14195, Berlin, Germany
| | - Mark A Hancock
- SPR-MS Facility, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Wiesje M van der Flier
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, 1081HZ, The Netherlands
| | - Peter Kunach
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Alzheimer's Disease Research Unit, Douglas Research Institute, McGill University, Montreal, H4H 1R3, QC, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Alzheimer's Disease Research Unit, Douglas Research Institute, McGill University, Montreal, H4H 1R3, QC, Canada
| | - Philip Scheltens
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, 1081HZ, The Netherlands
| | - Judes Poirier
- Department of Psychiatry, McGill University, Montreal, QC, H4H 1R3, Canada
| | - Paul Saftig
- Biochemisches Institut, Christian-Albrechts-Universität-Kiel, 24118, Kiel, Germany
| | - Randall J Bateman
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - John Breitner
- Department of Psychiatry, McGill University, Montreal, QC, H4H 1R3, Canada
| | - Christoph Hock
- Institute for Regenerative Medicine, University of Zurich, CH-8952, Schlieren, Switzerland.,Neurimmune, CH-8952, Schlieren, Switzerland
| | - Gerhard Multhaup
- Department of Pharmacology and Therapeutics and Integrated Program in Neuroscience, McGill University, Montreal, QC, H3G 1Y6, Canada.
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23
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Scholz D, Chernyshova Y, Ückert AK, Leist M. Reduced Aβ secretion by human neurons under conditions of strongly increased BACE activity. J Neurochem 2018; 147:256-274. [PMID: 29804308 DOI: 10.1111/jnc.14467] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/06/2018] [Accepted: 05/23/2018] [Indexed: 12/20/2022]
Abstract
The initial step in the amyloidogenic cascade of amyloid precursor protein (APP) processing is catalyzed by beta-site APP-cleaving enzyme (BACE), and this protease has increased activities in affected areas of Alzheimer's disease brains. We hypothesized that altered APP processing, because of augmented BACE activity, would affect the actions of direct and indirect BACE inhibitors. We therefore compared post-mitotic human neurons (LUHMES) with their BACE-overexpressing counterparts (BLUHMES). Although β-cleavage of APP was strongly increased in BLUHMES, they produced less full-length and truncated amyloid beta (Aβ) than LUHMES. Moreover, low concentrations of BACE inhibitors decreased cellular BACE activity as expected, but increased Aβ1-40 levels. Several other approaches to modulate BACE activity led to a similar, apparently paradoxical, behavior. For instance, reduction in intracellular acidification by bepridil increased Aβ production in parallel with decreased BACE activity. In contrast to BLUHMES, the respective control cells (LUHMES or BLUHMES with catalytically inactive BACE) showed conventional pharmacological responses. Other non-canonical neurochemical responses (so-called 'rebound effects') are well-documented for the Aβ pathway, especially for γ-secretase: a partial block of its activity leads to an increased Aβ secretion by some cell types. We therefore compared LUHMES and BLUHMES regarding rebound effects of γ-secretase inhibitors and found an Aβ rise in LUHMES but not in BLUHMES. Thus, different cellular factors are responsible for the γ-secretase- versus BACE-related Aβ rebound. We conclude that increased BACE activity, possibly accompanied by an altered cellular localization pattern, can dramatically influence Aβ generation in human neurons and affect pharmacological responses to secretase inhibitors. OPEN PRACTICES: Open Science: This manuscript was awarded with the Open Materials Badge. For more information see: https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Diana Scholz
- Chair for in vitro Toxicology and Biomedicine, University of Konstanz, Konstanz, Germany
| | - Yana Chernyshova
- Chair for in vitro Toxicology and Biomedicine, University of Konstanz, Konstanz, Germany
| | - Anna-Katharina Ückert
- Chair for in vitro Toxicology and Biomedicine, University of Konstanz, Konstanz, Germany
| | - Marcel Leist
- Chair for in vitro Toxicology and Biomedicine, University of Konstanz, Konstanz, Germany
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24
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Menendez-Gonzalez M, Padilla-Zambrano HS, Alvarez G, Capetillo-Zarate E, Tomas-Zapico C, Costa A. Targeting Beta-Amyloid at the CSF: A New Therapeutic Strategy in Alzheimer's Disease. Front Aging Neurosci 2018; 10:100. [PMID: 29713273 PMCID: PMC5911461 DOI: 10.3389/fnagi.2018.00100] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 03/26/2018] [Indexed: 12/17/2022] Open
Abstract
Although immunotherapies against the amyloid-β (Aβ) peptide tried so date failed to prove sufficient clinical benefit, Aβ still remains the main target in Alzheimer’s disease (AD). This article aims to show the rationale of a new therapeutic strategy: clearing Aβ from the CSF continuously (the “CSF-sink” therapeutic strategy). First, we describe the physiologic mechanisms of Aβ clearance and the resulting AD pathology when these mechanisms are altered. Then, we review the experiences with peripheral Aβ-immunotherapy and discuss the related hypothesis of the mechanism of action of “peripheral sink.” We also present Aβ-immunotherapies acting on the CNS directly. Finally, we introduce alternative methods of removing Aβ including the “CSF-sink” therapeutic strategy. As soluble peptides are in constant equilibrium between the ISF and the CSF, altering the levels of Aβ oligomers in the CSF would also alter the levels of such proteins in the brain parenchyma. We conclude that interventions based in a “CSF-sink” of Aβ will probably produce a steady clearance of Aβ in the ISF and therefore it may represent a new therapeutic strategy in AD.
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Affiliation(s)
- Manuel Menendez-Gonzalez
- Servicio de Neurologia, Hospital Universitario Central de Asturias, Oviedo, Spain.,Department of Cellular Morphology and Biology, University of Oviedo, Oviedo, Spain.,Instituto de Investigacion Sanitaria del Principado de Asturias, Oviedo, Spain
| | | | | | - Estibaliz Capetillo-Zarate
- Departamento de Neurociencias, Universidad del Pais Vasco (UPV/EHU), Leioa, Spain.,El Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Madrid, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Cristina Tomas-Zapico
- Instituto de Investigacion Sanitaria del Principado de Asturias, Oviedo, Spain.,Department of Functional Biology, University of Oviedo, Oviedo, Spain
| | - Agustin Costa
- Department of Physical and Analytical Chemistry, University of Oviedo, Oviedo, Spain
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25
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Doig AJ. Positive Feedback Loops in Alzheimer's Disease: The Alzheimer's Feedback Hypothesis. J Alzheimers Dis 2018; 66:25-36. [PMID: 30282364 PMCID: PMC6484277 DOI: 10.3233/jad-180583] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2018] [Indexed: 12/17/2022]
Abstract
The dominant model for Alzheimer's disease (AD) is the amyloid cascade hypothesis, in which the accumulation of excess amyloid-β (Aβ) leads to inflammation, excess glutamate and intracellular calcium, oxidative stress, tau hyperphosphorylation and tangle formation, neuronal loss, and ultimately dementia. In a cascade, AD proceeds in a unidirectional fashion, with events only affecting downstream processes. Compelling evidence now exists for the presence of positive feedback loops in AD, however, involving oxidative stress, inflammation, glutamate, calcium, and tau. The pathological state of AD is thus a system of positive feedback loops, leading to amplification of the initial perturbation, rather than a linear cascade. Drugs may therefore be effective by targeting numerous points within the loops, rather than concentrating on upstream processes. Anti-inflammatories and anti-oxidants may be especially valuable, since these processes are involved in many loops and hence would affect numerous processes in AD.
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Affiliation(s)
- Andrew J. Doig
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology Medicine and Health, Oxford Road, University of Manchester, UK
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26
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Li JM, Huang LL, Liu F, Tang BS, Yan XX. Can brain impermeable BACE1 inhibitors serve as anti-CAA medicine? BMC Neurol 2017; 17:163. [PMID: 28841840 PMCID: PMC5574137 DOI: 10.1186/s12883-017-0942-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/14/2017] [Indexed: 12/21/2022] Open
Abstract
Background Cerebral amyloid angiopathy (CAA) is characterized by the deposition of ß-amyloid peptides (Aß) in and surrounding the wall of microvasculature in the central nervous system, together with parenchymal amyloid plaques collectively referred to as cerebral amyloidosis, which occurs in the brain commonly among the elderly and more frequently in patients with Alzheimer’s disease (AD). CAA is associated with vascular injury and may cause devastating neurological outcomes. No therapeutic approach is available for this lesion to date. Main body ß-Secretase 1 (BACE1) is the enzyme initiating Aß production. Brain permeable BACE1 inhibitors targeting primarily at the parenchymal plaque pathology are currently evaluated in clinical trials. This article presents findings in support of a role of BACE1 elevation in the development of CAA, in addition to plaque pathogenesis. The rationale, feasibility, benefit and strategic issues for developing BACE1 inhibitors against CAA are discussed. Brain impermeable compounds are considered preferable as they might exhibit sufficient anti-CAA efficacy without causing significant neuronal/synaptic side effects. Conclusion Early pharmacological intervention to the pathogenesis of CAA is expected to provide significant protection for cerebral vascular health and hence brain health. Brain impermeable BACE1 inhibitors should be optimized and tested as potential anti-CAA therapeutics.
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Affiliation(s)
- Jian-Ming Li
- Department of Neurology & Key Laboratory of Hunan Province in Neurodegenerative Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.,Neuroscience Research Center, Changsha Medical University, Changsha, Hunan, 410219, China
| | - Li-Ling Huang
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China
| | - Fei Liu
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China
| | - Bei-Sha Tang
- Department of Neurology & Key Laboratory of Hunan Province in Neurodegenerative Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Xiao-Xin Yan
- Department of Neurology & Key Laboratory of Hunan Province in Neurodegenerative Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China. .,Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China.
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27
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McInerney MP, Short JL, Nicolazzo JA. Neurovascular Alterations in Alzheimer's Disease: Transporter Expression Profiles and CNS Drug Access. AAPS JOURNAL 2017; 19:940-956. [PMID: 28462473 DOI: 10.1208/s12248-017-0077-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 03/15/2017] [Indexed: 01/05/2023]
Abstract
Despite a century of steady and incremental progress toward understanding the underlying biochemical mechanisms, Alzheimer's disease (AD) remains a complicated and enigmatic disease, and greater insight will be necessary before substantive clinical success is realised. Over the last decade in particular, a large body of work has highlighted the cerebral microvasculature as an anatomical region with an increasingly apparent role in the pathogenesis of AD. The causative interplay and temporal cascade that manifest between the brain vasculature and the wider disease progression of AD are not yet fully understood, and further inquiry is required to properly characterise these relationships. The purpose of this review is to highlight the recent advancements in research implicating neurovascular factors in AD, at both the molecular and anatomical levels. We begin with a brief introduction of the biochemical and genetic aspects of AD, before reviewing the essential concepts of the blood-brain barrier (BBB) and the neurovascular unit (NVU). In detail, we then examine the evidence demonstrating involvement of BBB dysfunction in AD pathogenesis, highlighting the importance of neurovascular components in AD. Lastly, we include within this review research that focuses on how altered properties of the BBB in AD impact upon CNS exposure of therapeutic agents and the potential clinical impact that this may have on people with this disease.
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Affiliation(s)
- Mitchell P McInerney
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia
| | - Jennifer L Short
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, 3052, VIC, Australia
| | - Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia.
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28
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BACE1 across species: a comparison of the in vivo consequences of BACE1 deletion in mice and rats. Sci Rep 2017; 7:44249. [PMID: 28281673 PMCID: PMC5345047 DOI: 10.1038/srep44249] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 02/06/2017] [Indexed: 01/18/2023] Open
Abstract
Assessing BACE1 (β-site APP cleaving enzyme 1) knockout mice for general health and neurological function may be useful in predicting risks associated with prolonged pharmacological BACE1 inhibition, a treatment approach currently being developed for Alzheimer’s disease. To determine whether BACE1 deletion-associated effects in mice generalize to another species, we developed a novel Bace1−/− rat line using zinc-finger nuclease technology and compared Bace1−/− mice and rats with their Bace1+/+ counterparts. Lack of BACE1 was confirmed in Bace1−/− animals from both species. Removal of BACE1 affected startle magnitude, balance beam performance, pain response, and nerve myelination in both species. While both mice and rats lacking BACE1 have shown increased mortality, the increase was smaller and restricted to early developmental stages for rats. Bace1−/− mice and rats further differed in body weight, spontaneous locomotor activity, and prepulse inhibition of startle. While the effects of species and genetic background on these phenotypes remain difficult to distinguish, our findings suggest that BACE1’s role in myelination and some sensorimotor functions is consistent between mice and rats and may be conserved in other species. Other phenotypes differ between these models, suggesting that some effects of BACE1 inhibition vary with the biological context (e.g. species or background strain).
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29
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Portelius E, Mattsson N, Pannee J, Zetterberg H, Gisslén M, Vanderstichele H, Gkanatsiou E, Crespi GAN, Parker MW, Miles LA, Gobom J, Blennow K. Ex vivo 18O-labeling mass spectrometry identifies a peripheral amyloid β clearance pathway. Mol Neurodegener 2017; 12:18. [PMID: 28219449 PMCID: PMC5317049 DOI: 10.1186/s13024-017-0152-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 01/06/2017] [Indexed: 01/26/2023] Open
Abstract
Background Proteolytic degradation of amyloid β (Aβ) peptides has been intensely studied due to the central role of Aβ in Alzheimer’s disease (AD) pathogenesis. While several enzymes have been shown to degrade Aβ peptides, the main pathway of Aβ degradation in vivo is unknown. Cerebrospinal fluid (CSF) Aβ42 is reduced in AD, reflecting aggregation and deposition in the brain, but low CSF Aβ42 is, for unknown reasons, also found in some inflammatory brain disorders such as bacterial meningitis. Method Using 18O-labeling mass spectrometry and immune-affinity purification, we examined endogenous proteolytic processing of Aβ in human CSF. Results The Aβ peptide profile was stable in CSF samples from healthy controls but in CSF samples from patients with bacterial meningitis, showing increased leukocyte cell count, 18O-labeling mass spectrometry identified proteolytic activities degrading Aβ into several short fragments, including abundant Aβ1–19 and 1–20. After antibiotic treatment, no degradation of Aβ was detected. In vitro experiments located the source of the proteolytic activity to blood components, including leukocytes and erythrocytes, with insulin-degrading enzyme as the likely protease. A recombinant version of the mid-domain anti-Aβ antibody solanezumab was found to inhibit insulin-degrading enzyme-mediated Aβ degradation. Conclusion 18O labeling-mass spectrometry can be used to detect endogenous proteolytic activity in human CSF. Using this technique, we found an enzymatic activity that was identified as insulin-degrading enzyme that cleaves Aβ in the mid-domain of the peptide, and could be inhibited by a recombinant version of the mid-domain anti-Aβ antibody solanezumab. Electronic supplementary material The online version of this article (doi:10.1186/s13024-017-0152-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Erik Portelius
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, University Hospital, SE-431 80, Mölndal, Sweden
| | - Niklas Mattsson
- Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund, Sweden.,Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Josef Pannee
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, University Hospital, SE-431 80, Mölndal, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, University Hospital, SE-431 80, Mölndal, Sweden.,Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
| | - Magnus Gisslén
- Department of Infectious Diseases, Institute of Biomedicine, the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | | | - Eleni Gkanatsiou
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden
| | | | - Michael W Parker
- St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia.,Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, Australia
| | - Luke A Miles
- St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia.,Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, Australia
| | - Johan Gobom
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden. .,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, University Hospital, SE-431 80, Mölndal, Sweden.
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, University Hospital, SE-431 80, Mölndal, Sweden
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30
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Butler CR, Ogilvie K, Martinez-Alsina L, Barreiro G, Beck EM, Nolan CE, Atchison K, Benvenuti E, Buzon L, Doran S, Gonzales C, Helal CJ, Hou X, Hsu MH, Johnson EF, Lapham K, Lanyon L, Parris K, O'Neill BT, Riddell D, Robshaw A, Vajdos F, Brodney MA. Aminomethyl-Derived Beta Secretase (BACE1) Inhibitors: Engaging Gly230 without an Anilide Functionality. J Med Chem 2016; 60:386-402. [PMID: 27997172 PMCID: PMC5461923 DOI: 10.1021/acs.jmedchem.6b01451] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
![]()
A growing subset of β-secretase
(BACE1) inhibitors for the
treatment of Alzheimer’s disease (AD) utilizes an anilide chemotype
that engages a key residue (Gly230) in the BACE1 binding site. Although
the anilide moiety affords excellent potency, it simultaneously introduces
a third hydrogen bond donor that limits brain availability and provides
a potential metabolic site leading to the formation of an aniline,
a structural motif of prospective safety concern. We report herein
an alternative aminomethyl linker that delivers similar potency and
improved brain penetration relative to the amide moiety. Optimization
of this series identified analogues with an excellent balance of ADME
properties and potency; however, potential drug–drug interactions
(DDI) were predicted based on CYP 2D6 affinities. Generation and analysis
of key BACE1 and CYP 2D6 crystal structures identified strategies
to obviate the DDI liability, leading to compound 16,
which exhibits robust in vivo efficacy as a BACE1 inhibitor.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Mei-Hui Hsu
- Molecular and Experimental Medicine, The Scripps Research Institute , 10550 Torrey Pines Road, La Jolla, California 92024, United States
| | - Eric F Johnson
- Molecular and Experimental Medicine, The Scripps Research Institute , 10550 Torrey Pines Road, La Jolla, California 92024, United States
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31
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Eketjäll S, Janson J, Kaspersson K, Bogstedt A, Jeppsson F, Fälting J, Haeberlein SB, Kugler AR, Alexander RC, Cebers G. AZD3293: A Novel, Orally Active BACE1 Inhibitor with High Potency and Permeability and Markedly Slow Off-Rate Kinetics. J Alzheimers Dis 2016; 50:1109-23. [PMID: 26890753 PMCID: PMC4927864 DOI: 10.3233/jad-150834] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A growing body of pathological, biomarker, genetic, and mechanistic data suggests that amyloid accumulation, as a result of changes in production, processing, and/or clearance of brain amyloid-β peptide (Aβ) concentrations, plays a key role in the pathogenesis of Alzheimer’s disease (AD). Beta-secretase 1 (BACE1) mediates the first step in the processing of amyloid-β protein precursor (AβPP) to Aβ peptides, with the soluble N terminal fragment of AβPP (sAβPPβ) as a direct product, and BACE1 inhibition is an attractive target for therapeutic intervention to reduce the production of Aβ. Here, we report the in vitro and in vivo pharmacological profile of AZD3293, a potent, highly permeable, orally active, blood-brain barrier (BBB) penetrating, BACE1 inhibitor with unique slow off-rate kinetics. The in vitro potency of AZD3293 was demonstrated in several cellular models, including primary cortical neurons. In vivo in mice, guinea pigs, and dogs, AZD3293 displayed significant dose- and time-dependent reductions in plasma, cerebrospinal fluid, and brain concentrations of Aβ40, Aβ42, and sAβPPβ. The in vitro potency of AZD3293 in mouse and guinea pig primary cortical neuronal cells was correlated to the in vivo potency expressed as free AZD3293 concentrations in mouse and guinea pig brains. In mice and dogs, the slow off-rate from BACE1 may have translated into a prolongation of the observed effect beyond the turnover rate of Aβ. The preclinical data strongly support the clinical development of AZD3293, and patients with AD are currently being recruited into a combined Phase 2/3 study to test the disease-modifying properties of AZD3293.
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Affiliation(s)
- Susanna Eketjäll
- AstraZeneca Translational Sciences Centre, Science for Life Laboratory, Personal Healthcare and Biomarkers, AstraZeneca, Solna, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, Solna, Sweden
| | - Juliette Janson
- AstraZeneca Translational Sciences Centre, Science for Life Laboratory, Personal Healthcare and Biomarkers, AstraZeneca, Solna, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, Solna, Sweden
| | | | - Anna Bogstedt
- AstraZeneca Translational Sciences Centre, Science for Life Laboratory, Personal Healthcare and Biomarkers, AstraZeneca, Solna, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, Solna, Sweden
| | - Fredrik Jeppsson
- CNS and Pain iMed, AstraZeneca, Södertälje, Sweden.,Operations Global Quality, AstraZeneca, Södertälje, Sweden
| | | | | | - Alan R Kugler
- Neuroscience iMed, IMED Biotech Unit, AstraZeneca, Cambridge, MA, USA
| | | | - Gvido Cebers
- Neuroscience iMed, IMED Biotech Unit, AstraZeneca, Cambridge, MA, USA
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32
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Cebers G, Alexander RC, Haeberlein SB, Han D, Goldwater R, Ereshefsky L, Olsson T, Ye N, Rosen L, Russell M, Maltby J, Eketjäll S, Kugler AR. AZD3293: Pharmacokinetic and Pharmacodynamic Effects in Healthy Subjects and Patients with Alzheimer’s Disease. J Alzheimers Dis 2016; 55:1039-1053. [DOI: 10.3233/jad-160701] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
| | | | | | - David Han
- PAREXEL, Early Phase Clinical Unit, Glendale, CA, USA
| | - Ronald Goldwater
- PAREXEL, Clinical Pharmacology Research Unit, Harbor Hospital, Baltimore, MD, USA
| | | | | | - Naidong Ye
- AstraZeneca, Neuroscience, Waltham, MA, USA
| | | | - Muir Russell
- AstraZeneca, Protein Biomarkers, Personalised Healthcare and Biomarkers, Alderley Park, UK
| | - Justine Maltby
- AstraZeneca, Protein Biomarkers, Personalised Healthcare and Biomarkers, Alderley Park, UK
| | - Susanna Eketjäll
- AstraZeneca Integrated Cardio Metabolic Centre, Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, Karolinska Institutet, Solna, Sweden
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33
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Kucheryavykh LY, Dávila-Rodríguez J, Rivera-Aponte DE, Zueva LV, Washington AV, Sanabria P, Inyushin MY. Platelets are responsible for the accumulation of β-amyloid in blood clots inside and around blood vessels in mouse brain after thrombosis. Brain Res Bull 2016; 128:98-105. [PMID: 27908798 DOI: 10.1016/j.brainresbull.2016.11.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 11/21/2016] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Platelets contain beta-amyloid precursor protein (APP) as well as Aβ peptide (Aβ) that can be released upon activation. During thrombosis, platelets are concentrated in clots and activated. METHODS We used in vivo fluorescent analysis and electron microscopy in mice to determine to what degree platelets are concentrated in clots. We used immunostaining to visualize Aβ after photothrombosis in mouse brains. RESULTS Both in vivo results and electron microscopy revealed that platelets were 300-500 times more concentrated in clots than in non-clotted blood. After thrombosis in control mice, but not in thrombocytopenic animals, Aβ immunofluorescence was present inside blood vessels in the visual cortex and around capillaries in the entorhinal cortex. CONCLUSION The increased concentration of platelets allows enhanced release of Aβ during thrombosis, suggesting an additional source of Aβ in the brains of Alzheimer's patients that may arise if frequent micro-thrombosis events occur in their brains.
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Affiliation(s)
- Lilia Y Kucheryavykh
- Department of Biochemistry, School of Medicine, Universidad Central del Caribe, Bayamon, PR 00960-6032, (P.O. Box 60327), USA.
| | - Josué Dávila-Rodríguez
- School of Medicine, Universidad Central del Caribe, Bayamon, PR 00960-6032, (P.O. Box 60327), USA.
| | - David E Rivera-Aponte
- Department of Biochemistry, School of Medicine, Universidad Central del Caribe, Bayamon, PR 00960-6032, (P.O. Box 60327), USA.
| | - Lidia V Zueva
- Department of Physics, University of Puerto Rico Rio Piedras, San Juan, PR 00936, USA.
| | - A Valance Washington
- Department of Anatomy, School of Medicine, Universidad Central del Caribe, Bayamon, PR 00960-6032, (P.O. Box 60327), USA; The Department of Biology, University of Puerto Rico Rio Piedras, San Juan, PR 00936, USA.
| | - Priscilla Sanabria
- Department of Physiology, School of Medicine, Universidad Central del Caribe, Bayamon, PR 00960-6032, (P.O. Box 60327), USA.
| | - Mikhail Y Inyushin
- Department of Physiology, School of Medicine, Universidad Central del Caribe, Bayamon, PR 00960-6032, (P.O. Box 60327), USA.
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Xue ZQ, He ZW, Yu JJ, Cai Y, Qiu WY, Pan A, Gai WP, Cai H, Luo XG, Ma C, Yan XX. Non-neuronal and neuronal BACE1 elevation in association with angiopathic and leptomeningeal β-amyloid deposition in the human brain. BMC Neurol 2015; 15:71. [PMID: 25934480 PMCID: PMC4428107 DOI: 10.1186/s12883-015-0327-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Accepted: 04/21/2015] [Indexed: 12/14/2022] Open
Abstract
Background Cerebral amyloid angiopathy (CAA) refers to the deposition of β-amyloid (Aβ) peptides in the wall of brain vasculature, commonly involving capillaries and arterioles. Also being considered a part of CAA is the Aβ deposition in leptomeninge. The cellular origin of angiopathic Aβ and the pathogenic course of CAA remain incompletely understood. Methods The present study was aimed to explore the pathogenic course of CAA in the human cerebrum via examination of changes in β-secretase-1 (BACE1), the obligatory Aβ producing enzyme, relative to Aβ and other cellular markers, by neuroanatomical and biochemical characterizations with postmortem brain samples and primary cell cultures. Results Immunoreactivity (IR) for BACE1 was essentially not visible at vasculature in cases without cerebral amyloidosis (control group, n = 15, age = 86.1 ± 10.3 year). In cases with brain amyloid pathology (n = 15, age = 78.7 ± 12.7 year), increased BACE1 IR was identified locally at capillaries, arterioles and along the pia, localizing to endothelia, perivascular dystrophic neurites and meningeal cells, and often coexisting with vascular iron deposition. Double immunofluorescence with densitometric analysis confirmed a site-specific BACE1 elevation at cerebral arterioles in the development of vascular Aβ deposition. Levels of BACE1 protein, activity and its immediate product (C99) were elevated in leptomeningeal lysates from cases with CAA relative to controls. The expression of BACE1 and other amyloidogenic proteins in the endothelial and meningeal cells was confirmed in primary cultures prepared from human leptomeningeal and arteriolar biopsies. Conclusion These results suggest that BACE1 elevation in the endothelia and perivascular neurites may be involved in angiopathic Aβ deposition, while BACE1 elevation in meningeal cells might contribute Aβ to leptomeningeal amyloidosis.
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Affiliation(s)
- Zhi-Qin Xue
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China. .,Department of Anatomy, Xinjiang Medical University, Urumqi, Xinjiang, 830011, China.
| | - Zheng-Wen He
- Central South University Affiliated Tumor Hospital, Changsha, Hunan, 410006, China.
| | - Jian-Jun Yu
- Central South University Affiliated Tumor Hospital, Changsha, Hunan, 410006, China.
| | - Yan Cai
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China.
| | - Wen-Ying Qiu
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100730, China.
| | - Aihua Pan
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China.
| | - Wei-Ping Gai
- Department of Surgery and Centre for Neuroscience, Flinders University School of Medicine, Bedford Park, SA, 5042, Australia.
| | - Huaibin Cai
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Xue-Gang Luo
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China.
| | - Chao Ma
- Department of Human Anatomy, Histology and Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100730, China.
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China.
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