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Iwata N, Tsubuki S, Sekiguchi M, Watanabe-Iwata K, Matsuba Y, Kamano N, Fujioka R, Takamura R, Watamura N, Kakiya N, Mihira N, Morito T, Shirotani K, Mann DM, Robinson AC, Hashimoto S, Sasaguri H, Saito T, Higuchi M, Saido TC. Metabolic resistance of Aβ3pE-42, a target epitope of the anti-Alzheimer therapeutic antibody, donanemab. Life Sci Alliance 2024; 7:e202402650. [PMID: 39348937 PMCID: PMC11443169 DOI: 10.26508/lsa.202402650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 09/06/2024] [Accepted: 09/06/2024] [Indexed: 10/02/2024] Open
Abstract
The amyloid β peptide (Aβ), starting with pyroglutamate (pE) at position 3 and ending at position 42 (Aβ3pE-42), predominantly accumulates in the brains of Alzheimer's disease. Consistently, donanemab, a therapeutic antibody raised against Aβ3pE-42, has been shown to be effective in recent clinical trials. Although the primary Aβ produced physiologically is Aβ1-40/42, an explanation for how and why this physiological Aβ is converted to the pathological form remains elusive. Here, we present experimental evidence that accounts for the aging-associated Aβ3pE-42 deposition: Aβ3pE-42 was metabolically more stable than other Aβx-42 variants; deficiency of neprilysin, the major Aβ-degrading enzyme, induced a relatively selective deposition of Aβ3pE-42 in both APP transgenic and App knock-in mouse brains; Aβ3pE-42 deposition always colocalized with Pittsburgh compound B-positive cored plaques in APP transgenic mouse brains; and under aberrant conditions, such as a significant reduction in neprilysin activity, aminopeptidases, dipeptidyl peptidases, and glutaminyl-peptide cyclotransferase-like were up-regulated in the progression of aging, and a proportion of Aβ1-42 may be processed to Aβ3pE-42. Our findings suggest that anti-Aβ therapies are more effective if given before Aβ3pE-42 deposition.
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Affiliation(s)
- Nobuhisa Iwata
- https://ror.org/058h74p94 Department of Genome-Based Drug Discovery and Leading Medical Research Core Unit, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Satoshi Tsubuki
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Misaki Sekiguchi
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Kaori Watanabe-Iwata
- https://ror.org/058h74p94 Department of Genome-Based Drug Discovery and Leading Medical Research Core Unit, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yukio Matsuba
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Naoko Kamano
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Ryo Fujioka
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Risa Takamura
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Naoto Watamura
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Naomasa Kakiya
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Naomi Mihira
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Takahiro Morito
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Keiro Shirotani
- https://ror.org/058h74p94 Department of Genome-Based Drug Discovery and Leading Medical Research Core Unit, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - David Ma Mann
- https://ror.org/027m9bs27 Division of Neuroscience, Faculty of Biology, Medicine and Health, School of Biological Sciences, Faculty of Biology, Medicine and Health, School of Biological Sciences, The University of Manchester, Salford Royal Hospital, Salford, UK
| | - Andrew C Robinson
- https://ror.org/027m9bs27 Division of Neuroscience, Faculty of Biology, Medicine and Health, School of Biological Sciences, Faculty of Biology, Medicine and Health, School of Biological Sciences, The University of Manchester, Salford Royal Hospital, Salford, UK
| | - Shoko Hashimoto
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Hiroki Sasaguri
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Makoto Higuchi
- Department of Functional Brain Imaging, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Takaomi C Saido
- https://ror.org/04j1n1c04 Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Saitama, Japan
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2
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Mardanyan S, Sharoyan S, Antonyan A. Diversity of amyloid beta peptide actions. Rev Neurosci 2024; 35:387-398. [PMID: 38281140 DOI: 10.1515/revneuro-2023-0100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 12/16/2023] [Indexed: 01/30/2024]
Abstract
Fibril formation by amyloidogenic proteins and peptides is considered the cause of a number of incurable diseases. One of the most known amyloid diseases is Alzheimer's disease (AD). Traditionally, amyloidogenic beta peptides Aβ40 and Aβ42 (Aβs) are considered as main causes of AD and the foremost targets in AD fight. The main efforts in pharmacology are aimed at reducing Aβs concentration to prevent their accumulation, aggregation, formation of senile plaques, neuronal death, and neurodegeneration. However, a number of publications have demonstrated certain beneficial physiological effects of Aβs. Simultaneously, it is indicated that the effects of Aβs turn into pathological due to the development of certain diseases in the body. The accumulation of C- and N-terminal truncated Aβs under diverse conditions is supposed to play a role in AD development. The significance of transformation of glutamate residue at positions 3 or 11 of Aβs catalyzed by glutaminyl cyclase making them more degradation resistant, hydrophobic, and prone to aggregation, as well as the participation of dipeptidyl peptidase IV in these transformations are discussed. The experimental data presented confirm the maintenance of physiological, nonaggregated state of Aβs by plant preparations. In conclusion, this review suggests that in the fight against AD, instead of removing Aβs, preference should be given to the treatment of common diseases. Glutaminyl cyclase and dipeptidyl peptidase IV can be considered as targets in AD treatment. Flavonoids and plant preparations that possess antiamyloidogenic propensity are proposed as beneficial neuroprotective, anticancer, and antidiabetic food additives.
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Affiliation(s)
- Sona Mardanyan
- H. Buniatian Institute of Biochemistry of Armenian National Academy of Sciences, Yerevan 0014, Republic of Armenia
| | - Svetlana Sharoyan
- H. Buniatian Institute of Biochemistry of Armenian National Academy of Sciences, Yerevan 0014, Republic of Armenia
| | - Alvard Antonyan
- H. Buniatian Institute of Biochemistry of Armenian National Academy of Sciences, Yerevan 0014, Republic of Armenia
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3
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Jiang X, Li J, Yao X, Ding H, Gu A, Zhou Z. Neuroprotective effects of dipeptidyl peptidase 4 inhibitor on Alzheimer's disease: a narrative review. Front Pharmacol 2024; 15:1361651. [PMID: 38405664 PMCID: PMC10884281 DOI: 10.3389/fphar.2024.1361651] [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: 12/26/2023] [Accepted: 01/30/2024] [Indexed: 02/27/2024] Open
Abstract
Insulin resistance in brain and amyloidogenesis are principal pathological features of diabetes-related cognitive decline and development of Alzheimer's disease (AD). A growing body of evidence suggests that maintaining glucose under control in diabetic patients is beneficial for preventing AD development. Dipeptidyl peptidase 4 inhibitors (DDP4is) are a class of novel glucose-lowering medications through increasing insulin excretion and decreasing glucagon levels that have shown neuroprotective potential in recent studies. This review consolidates extant evidence from earlier and new studies investigating the association between DPP4i use, AD, and other cognitive outcomes. Beyond DPP4i's benefits in alleviating insulin resistance and glucose-lowering, underlying mechanisms for the potential neuroprotection with DPP4i medications were categorized into the following sections: (Ferrari et al., Physiol Rev, 2021, 101, 1,047-1,081): the benefits of DPP4is on directly ameliorating the burden of β-amyloid plaques and reducing the formation of neurofibrillary tangles; DPP4i increasing the bioactivity of neuroprotective DPP4 substrates including glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and stromal-derived factor-1α (SDF-1α) etc.; pleiotropic effects of DPP4is on neuronal cells and intracerebral structure including anti-inflammation, anti-oxidation, and anti-apoptosis. We further revisited recently published epidemiological studies that provided supportive data to compliment preclinical evidence. Given that there remains a lack of completed randomized trials that aim at assessing the effect of DPP4is in preventing AD development and progression, this review is expected to provide a useful insight into DPP4 inhibition as a potential therapeutic target for AD prevention and treatment. The evidence is helpful for informing the rationales of future clinical research and guiding evidence-based clinical practice.
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Affiliation(s)
- Xin Jiang
- Baoying People’s Hospital, Yangzhou, China
| | | | | | - Hao Ding
- Baoying People’s Hospital, Yangzhou, China
| | - Aihong Gu
- Baoying People’s Hospital, Yangzhou, China
| | - Zhen Zhou
- School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
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4
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Abubakar M, Nama L, Ansari MA, Ansari MM, Bhardwaj S, Daksh R, Syamala KLV, Jamadade MS, Chhabra V, Kumar D, Kumar N. GLP-1/GIP Agonist as an Intriguing and Ultimate Remedy for Combating Alzheimer's Disease through its Supporting DPP4 Inhibitors: A Review. Curr Top Med Chem 2024; 24:1635-1664. [PMID: 38803170 DOI: 10.2174/0115680266293416240515075450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 04/14/2024] [Accepted: 04/22/2024] [Indexed: 05/29/2024]
Abstract
BACKGROUND Alzheimer's disease (AD) is a widespread neurological illness in the elderly, which impacted about 50 million people globally in 2020. Type 2 diabetes has been identified as a risk factor. Insulin and incretins are substances that have various impacts on neurodegenerative processes. Preclinical research has shown that GLP-1 receptor agonists decrease neuroinflammation, tau phosphorylation, amyloid deposition, synaptic function, and memory formation. Phase 2 and 3 studies are now occurring in Alzheimer's disease populations. In this article, we present a detailed assessment of the therapeutic potential of GLP-1 analogues and DPP4 inhibitors in Alzheimer's disease. AIM This study aimed to gain insight into how GLP-1 analogues and associated antagonists of DPP4 safeguard against AD. METHODS This study uses terms from search engines, such as Scopus, PubMed, and Google Scholar, to explore the role, function, and treatment options of the GLP-1 analogue for AD. RESULTS The review suggested that GLP-1 analogues may be useful for treating AD because they have been linked to anti-inflammatory, neurotrophic, and neuroprotective characteristics. Throughout this review, we discuss the underlying causes of AD and how GLP signaling functions. CONCLUSION With a focus on AD, the molecular and pharmacological effects of a few GLP-1/GIP analogs, both synthetic and natural, as well as DPP4 inhibitors, have been mentioned, which are in the preclinical and clinical studies. This has been demonstrated to improve cognitive function in Alzheimer's patients.
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Affiliation(s)
- Mohammad Abubakar
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Lokesh Nama
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Mohammad Arif Ansari
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Mohammad Mazharuddin Ansari
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Shivani Bhardwaj
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Rajni Daksh
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Katta Leela Venkata Syamala
- Department of Regulatory and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Mohini Santosh Jamadade
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Vishal Chhabra
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
| | - Dileep Kumar
- Poona College of Pharmacy, Bharati Vidyapeeth (Deemed to be) University, Pune, Maharashtra, 411038, India
- Department of Entomology, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA
| | - Nitesh Kumar
- Department of Pharmacology and Toxicology, National Institution of Pharmaceutical Education and Research, Hajipur, Vaishali, 844102, Bihar, India
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5
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Coimbra JRM, Moreira PI, Santos AE, Salvador JAR. Therapeutic potential of glutaminyl cyclases: Current status and emerging trends. Drug Discov Today 2023; 28:103644. [PMID: 37244566 DOI: 10.1016/j.drudis.2023.103644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/11/2023] [Accepted: 05/22/2023] [Indexed: 05/29/2023]
Abstract
Glutaminyl cyclase (QC) activity has been identified as a key effector in distinct biological processes. Human glutaminyl-peptide cyclotransferase (QPCT) and glutaminyl-peptide cyclotransferase-like (QPCTL) are considered attractive therapeutic targets in many human disorders, such as neurodegenerative diseases, and a range of inflammatory conditions, as well as for cancer immunotherapy, because of their capacity to modulate cancer immune checkpoint proteins. In this review, we explore the biological functions and structures of QPCT/L enzymes and highlight their therapeutic relevance. We also summarize recent developments in the discovery of small-molecule inhibitors targeting these enzymes, including an overview of preclinical and clinical studies.
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Affiliation(s)
- Judite R M Coimbra
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal; Center for Neuroscience and Cell Biology (CNC), Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Paula I Moreira
- Center for Neuroscience and Cell Biology (CNC), Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal; Laboratory of Physiology, Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Armanda E Santos
- Center for Neuroscience and Cell Biology (CNC), Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal; Laboratory of Biochemistry and Biology, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal.
| | - Jorge A R Salvador
- Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal; Center for Neuroscience and Cell Biology (CNC), Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal.
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6
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Kemeh MM, Lazo ND. Modulation of the Activity of the Insulin-Degrading Enzyme by Aβ Peptides. ACS Chem Neurosci 2023; 14:2935-2943. [PMID: 37498802 DOI: 10.1021/acschemneuro.3c00384] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023] Open
Abstract
The insulin-degrading enzyme (IDE) is an evolutionarily conserved protease implicated in the degradation of insulin and amyloidogenic peptides. Most of the biochemical and biophysical characterization of IDE's catalytic activity has been conducted using solutions containing a single substrate, i.e., insulin or Aβ(1-40). IDE's activity toward a particular substrate, however, is likely to be influenced by the presence of other substrates. Here, we show by a kinetic assay based on insulin's helical circular dichroic signal and MALDI TOF mass spectrometry that Aβ peptides modulate IDE's activity toward insulin in opposing ways. Aβ(1-40) enhances IDE-dependent degradation of insulin, whereas Aβ(pyroE3-42), the most pathogenic pyroglutamate-modified Aβ peptide in AD, inhibits IDE's activity. Intriguingly, Aβ(pyroE3-42) also inhibits IDE's ability to degrade Aβ(1-40). Together, our results implicate Aβ peptides in the abnormal catabolism of IDE's key substrates.
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Affiliation(s)
- Merc M Kemeh
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, Worcester, Massachusetts 01610, United States
| | - Noel D Lazo
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, Worcester, Massachusetts 01610, United States
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7
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Frackowiak J, Mazur-Kolecka B. Intraneuronal accumulation of amyloid-β peptides as the pathomechanism linking autism and its co-morbidities: epilepsy and self-injurious behavior - the hypothesis. Front Mol Neurosci 2023; 16:1160967. [PMID: 37305553 PMCID: PMC10250631 DOI: 10.3389/fnmol.2023.1160967] [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: 02/07/2023] [Accepted: 04/28/2023] [Indexed: 06/13/2023] Open
Abstract
Autism spectrum disorder (ASD) is associated with enhanced processing of amyloid-β precursor protein (APP) by secretase-α, higher blood levels of sAPPα and intraneuronal accumulation of N-terminally truncated Aβ peptides in the brain cortex - mainly in the GABAergic neurons expressing parvalbumin - and subcortical structures. Brain Aβ accumulation has been also described in epilepsy-the frequent ASD co-morbidity. Furthermore, Aβ peptides have been shown to induce electroconvulsive episodes. Enhanced production and altered processing of APP, as well as accumulation of Aβ in the brain are also frequent consequences of traumatic brain injuries which result from self-injurious behaviors, another ASD co-morbidity. We discuss distinct consequences of accumulation of Aβ in the neurons and synapses depending on the Aβ species, their posttranslational modifications, concentration, level of aggregation and oligomerization, as well as brain structures, cell types and subcellular structures where it occurs. The biological effects of Aβ species which are discussed in the context of the pathomechanisms of ASD, epilepsy, and self-injurious behavior include modulation of transcription-both activation and repression; induction of oxidative stress; activation and alteration of membrane receptors' signaling; formation of calcium channels causing hyper-activation of neurons; reduction of GABAergic signaling - all of which lead to disruption of functions of synapses and neuronal networks. We conclude that ASD, epilepsy, and self-injurious behaviors all contribute to the enhanced production and accumulation of Aβ peptides which in turn cause and enhance dysfunctions of the neuronal networks that manifest as autism clinical symptoms, epilepsy, and self-injurious behaviors.
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8
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Bernstein HG, Keilhoff G, Dobrowolny H, Steiner J. The many facets of CD26/dipeptidyl peptidase 4 and its inhibitors in disorders of the CNS - a critical overview. Rev Neurosci 2023; 34:1-24. [PMID: 35771831 DOI: 10.1515/revneuro-2022-0026] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 05/10/2022] [Indexed: 01/11/2023]
Abstract
Dipeptidyl peptidase 4 is a serine protease that cleaves X-proline or X-alanine in the penultimate position. Natural substrates of the enzyme are glucagon-like peptide-1, glucagon inhibiting peptide, glucagon, neuropeptide Y, secretin, substance P, pituitary adenylate cyclase-activating polypeptide, endorphins, endomorphins, brain natriuretic peptide, beta-melanocyte stimulating hormone and amyloid peptides as well as some cytokines and chemokines. The enzyme is involved in the maintenance of blood glucose homeostasis and regulation of the immune system. It is expressed in many organs including the brain. DPP4 activity may be effectively depressed by DPP4 inhibitors. Apart from enzyme activity, DPP4 acts as a cell surface (co)receptor, associates with adeosine deaminase, interacts with extracellular matrix, and controls cell migration and differentiation. This review aims at revealing the impact of DPP4 and DPP4 inhibitors for several brain diseases (virus infections affecting the brain, tumours of the CNS, neurological and psychiatric disorders). Special emphasis is given to a possible involvement of DPP4 expressed in the brain.While prominent contributions of extracerebral DPP4 are evident for a majority of diseases discussed herein; a possible role of "brain" DPP4 is restricted to brain cancers and Alzheimer disease. For a number of diseases (Covid-19 infection, type 2 diabetes, Alzheimer disease, vascular dementia, Parkinson disease, Huntington disease, multiple sclerosis, stroke, and epilepsy), use of DPP4 inhibitors has been shown to have a disease-mitigating effect. However, these beneficial effects should mostly be attributed to the depression of "peripheral" DPP4, since currently used DPP4 inhibitors are not able to pass through the intact blood-brain barrier.
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Affiliation(s)
- Hans-Gert Bernstein
- Department of Psychiatry and Psychotherapy, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
| | - Gerburg Keilhoff
- Institute of Biochemistry and Cell Biology, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
| | - Henrik Dobrowolny
- Department of Psychiatry and Psychotherapy, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
| | - Johann Steiner
- Department of Psychiatry and Psychotherapy, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
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Solid-phase synthesis and pathological evaluation of pyroglutamate amyloid-β 3-42 peptide. Sci Rep 2023; 13:505. [PMID: 36627316 PMCID: PMC9831997 DOI: 10.1038/s41598-022-26616-x] [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: 08/22/2022] [Accepted: 12/16/2022] [Indexed: 01/11/2023] Open
Abstract
Pyroglutamate amyloid-β3-42 (AβpE3-42) is an N-terminally truncated and pyroglutamate-modified Aβ peptide retaining highly hydrophobic, amyloidogenic, and neurotoxic properties. In Alzheimer's disease (AD) patients, AβpE3-42 peptides accumulate into oligomers and induce cellular toxicity and synaptic dysfunction. AβpE3-42 aggregates further seed the formation of amyloid plaques, which are the pathological hallmarks of AD. Given that AβpE3-42 peptides play critical roles in the development of neurodegeneration, a reliable and reproducible synthetic access to these peptides may support pathological and medicinal studies of AD. Here, we synthesized AβpE3-42 peptides through the microwave-assisted solid-phase peptide synthesis (SPPS). Utilizing thioflavin T fluorescence assay and dot blotting analysis with anti-amyloid oligomer antibody, the amyloidogenic activity of synthesized AβpE3-42 peptides was confirmed. We further observed the cytotoxicity of AβpE3-42 aggregates in cell viability test. To examine the cognitive deficits induced by synthetic AβpE3-42 peptides, AβpE3-42 oligomers were intracerebroventricularly injected into imprinting control region mice and Y-maze and Morris water maze tests were performed. We found that AβpE3-42 aggregates altered the expression level of postsynaptic density protein 95 in cortical lysates. Collectively, we produced AβpE3-42 peptides in the microwave-assisted SPPS and evaluated the amyloidogenic and pathological function of the synthesized peptides.
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10
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Busch L, Eggert S, Endres K, Bufe B. The Hidden Role of Non-Canonical Amyloid β Isoforms in Alzheimer's Disease. Cells 2022; 11:3421. [PMID: 36359817 PMCID: PMC9654995 DOI: 10.3390/cells11213421] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 09/08/2024] Open
Abstract
Recent advances have placed the pro-inflammatory activity of amyloid β (Aβ) on microglia cells as the focus of research on Alzheimer's Disease (AD). Researchers are confronted with an astonishing spectrum of over 100 different Aβ variants with variable length and chemical modifications. With the exception of Aβ1-42 and Aβ1-40, the biological significance of most peptides for AD is as yet insufficiently understood. We therefore aim to provide a comprehensive overview of the contributions of these neglected Aβ variants to microglia activation. First, the impact of Aβ receptors, signaling cascades, scavenger mechanisms, and genetic variations on the physiological responses towards various Aβ species is described. Furthermore, we discuss the importance of different types of amyloid precursor protein processing for the generation of these Aβ variants in microglia, astrocytes, oligodendrocytes, and neurons, and highlight how alterations in secondary structures and oligomerization affect Aβ neurotoxicity. In sum, the data indicate that gene polymorphisms in Aβ-driven signaling pathways in combination with the production and activity of different Aβ variants might be crucial factors for the initiation and progression of different forms of AD. A deeper assessment of their interplay with glial cells may pave the way towards novel therapeutic strategies for individualized medicine.
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Affiliation(s)
- Lukas Busch
- Department of Informatics and Microsystems Technology, University of Applied Sciences Kaiserslautern, D-66482 Zweibruecken, Germany
| | - Simone Eggert
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, D-37075 Goettingen, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Centre of the Johannes Gutenberg University, D-55131 Mainz, Germany
| | - Bernd Bufe
- Department of Informatics and Microsystems Technology, University of Applied Sciences Kaiserslautern, D-66482 Zweibruecken, Germany
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11
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Morató X, Pytel V, Jofresa S, Ruiz A, Boada M. Symptomatic and Disease-Modifying Therapy Pipeline for Alzheimer's Disease: Towards a Personalized Polypharmacology Patient-Centered Approach. Int J Mol Sci 2022; 23:9305. [PMID: 36012569 PMCID: PMC9409252 DOI: 10.3390/ijms23169305] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 02/07/2023] Open
Abstract
Since 1906, when Dr. Alois Alzheimer first described in a patient "a peculiar severe disease process of the cerebral cortex", people suffering from this pathology have been waiting for a breakthrough therapy. Alzheimer's disease (AD) is an irreversible, progressive neurodegenerative brain disorder and the most common form of dementia in the elderly with a long presymptomatic phase. Worldwide, approximately 50 million people are living with dementia, with AD comprising 60-70% of cases. Pathologically, AD is characterized by the deposition of amyloid β-peptide (Aβ) in the neuropil (neuritic plaques) and blood vessels (amyloid angiopathy), and by the accumulation of hyperphosphorylated tau in neurons (neurofibrillary tangles) in the brain, with associated loss of synapses and neurons, together with glial activation, and neuroinflammation, resulting in cognitive deficits and eventually dementia. The current competitive landscape in AD consists of symptomatic treatments, of which there are currently six approved medications: three AChEIs (donepezil, rivastigmine, and galantamine), one NMDA-R antagonist (memantine), one combination therapy (memantine/donepezil), and GV-971 (sodium oligomannate, a mixture of oligosaccharides derived from algae) only approved in China. Improvements to the approved therapies, such as easier routes of administration and reduced dosing frequencies, along with the developments of new strategies and combined treatments are expected to occur within the next decade and will positively impact the way the disease is managed. Recently, Aducanumab, the first disease-modifying therapy (DMT) has been approved for AD, and several DMTs are in advanced stages of clinical development or regulatory review. Small molecules, mAbs, or multimodal strategies showing promise in animal studies have not confirmed that promise in the clinic (where small to moderate changes in clinical efficacy have been observed), and therefore, there is a significant unmet need for a better understanding of the AD pathogenesis and the exploration of alternative etiologies and therapeutic effective disease-modifying therapies strategies for AD. Therefore, a critical review of the disease-modifying therapy pipeline for Alzheimer's disease is needed.
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Affiliation(s)
- Xavier Morató
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
| | - Vanesa Pytel
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
| | - Sara Jofresa
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
| | - Agustín Ruiz
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Mercè Boada
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28029 Madrid, Spain
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12
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Pyroglutamate Aβ cascade as drug target in Alzheimer's disease. Mol Psychiatry 2022; 27:1880-1885. [PMID: 34880449 PMCID: PMC9126800 DOI: 10.1038/s41380-021-01409-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 02/07/2023]
Abstract
One of the central aims in Alzheimer's disease (AD) research is the identification of clinically relevant drug targets. A plethora of potential molecular targets work very well in preclinical model systems both in vitro and in vivo in AD mouse models. However, the lack of translation into clinical settings in the AD field is a challenging endeavor. Although it is long known that N-terminally truncated and pyroglutamate-modified Abeta (AβpE3) peptides are abundantly present in the brain of AD patients, form stable and soluble low-molecular weight oligomers, and induce neurodegeneration in AD mouse models, their potential as drug target has not been generally accepted in the past. This situation has dramatically changed with the report that passive immunization with donanemab, an AβpE3-specific antibody, cleared aymloid plaques and stabilized cognitive deficits in a group of patients with mild AD in a phase II trial. This review summarizes the current knowledge on the molecular mechanisms of generation of AβpE, its biochemical properties, and the intervention points as a drug target in AD.
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13
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Van Acker ZP, Perdok A, Bretou M, Annaert W. The microglial lysosomal system in Alzheimer's disease: Guardian against proteinopathy. Ageing Res Rev 2021; 71:101444. [PMID: 34391945 DOI: 10.1016/j.arr.2021.101444] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/14/2021] [Accepted: 08/08/2021] [Indexed: 12/12/2022]
Abstract
Microglia, the brain-resident immune cells, play an essential role in the upkeep of brain homeostasis. They actively adapt into specific activation states based on cues from the microenvironment. One of these encompasses the activated response microglia (ARMs) phenotype. It arises along a healthy aging process and in a range of neurodegenerative diseases, including Alzheimer's disease (AD). As the phenotype is characterized by an increased lipid metabolism, phagocytosis rate, lysosomal protease content and secretion of neuroprotective agents, it leaves to reason that the phenotype is adapted in an attempt to restore homeostasis. This is important to the conundrum of inflammatory processes. Inflammation per se may not be deleterious; it is only when microglial reactions become chronic or the microglial subtype is made dysfunctional by (multiple) risk proteins with single-nucleotide polymorphisms that microglial involvement becomes deleterious instead of beneficial. Interestingly, the ARMs up- and downregulate many late-onset AD-associated risk factor genes, the products of which are particularly active in the endolysosomal system. Hence, in this review, we focus on how the endolysosomal system is placed at the crossroad of inflammation and microglial capacity to keep pace with degradation.
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Hoffmann T, Rahfeld JU, Schenk M, Ponath F, Makioka K, Hutter-Paier B, Lues I, Lemere CA, Schilling S. Combination of the Glutaminyl Cyclase Inhibitor PQ912 (Varoglutamstat) and the Murine Monoclonal Antibody PBD-C06 (m6) Shows Additive Effects on Brain Aβ Pathology in Transgenic Mice. Int J Mol Sci 2021; 22:ijms222111791. [PMID: 34769222 PMCID: PMC8584206 DOI: 10.3390/ijms222111791] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/07/2021] [Accepted: 10/27/2021] [Indexed: 11/16/2022] Open
Abstract
Compelling evidence suggests that pyroglutamate-modified Aβ (pGlu3-Aβ; AβN3pG) peptides play a pivotal role in the development and progression of Alzheimer’s disease (AD). Approaches targeting pGlu3-Aβ by glutaminyl cyclase (QC) inhibition (Varoglutamstat) or monoclonal antibodies (Donanemab) are currently in clinical development. Here, we aimed at an assessment of combination therapy of Varoglutamstat (PQ912) and a pGlu3-Aβ-specific antibody (m6) in transgenic mice. Whereas the single treatments at subtherapeutic doses show moderate (16–41%) but statistically insignificant reduction of Aβ42 and pGlu-Aβ42 in mice brain, the combination of both treatments resulted in significant reductions of Aβ by 45–65%. Evaluation of these data using the Bliss independence model revealed a combination index of ≈1, which is indicative for an additive effect of the compounds. The data are interpreted in terms of different pathways, in which the two drugs act. While PQ912 prevents the formation of pGlu3-Aβ in different compartments, the antibody is able to clear existing pGlu3-Aβ deposits. The results suggest that combination of the small molecule Varoglutamstat and a pE3Aβ-directed monoclonal antibody may allow a reduction of the individual compound doses while maintaining the therapeutic effect.
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Affiliation(s)
- Torsten Hoffmann
- Vivoryon Therapeutics N.V., Weinbergweg 22, 06120 Halle, Germany;
- Correspondence: (T.H.); (S.S.)
| | - Jens-Ulrich Rahfeld
- Fraunhofer Institute for Cell Therapy and Immunology, Department of Drug Design and Target Validation, Weinbergweg 22, 06120 Halle, Germany; (J.-U.R.); (M.S.)
| | - Mathias Schenk
- Fraunhofer Institute for Cell Therapy and Immunology, Department of Drug Design and Target Validation, Weinbergweg 22, 06120 Halle, Germany; (J.-U.R.); (M.S.)
| | - Falk Ponath
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, 60 Fenwood Rd., Boston, MA 02115, USA; (F.P.); (K.M.); (C.A.L.)
| | - Koki Makioka
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, 60 Fenwood Rd., Boston, MA 02115, USA; (F.P.); (K.M.); (C.A.L.)
| | - Birgit Hutter-Paier
- QPS Austria GmbH, Department of Neuropharmacology, Parkring 12, A-8074 Grambach, Austria;
| | - Inge Lues
- Vivoryon Therapeutics N.V., Weinbergweg 22, 06120 Halle, Germany;
| | - Cynthia A. Lemere
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, 60 Fenwood Rd., Boston, MA 02115, USA; (F.P.); (K.M.); (C.A.L.)
| | - Stephan Schilling
- Fraunhofer Institute for Cell Therapy and Immunology, Department of Drug Design and Target Validation, Weinbergweg 22, 06120 Halle, Germany; (J.-U.R.); (M.S.)
- Anhalt University of Applied Sciences, Bernburger Straße 55, 06366 Köthen, Germany
- Correspondence: (T.H.); (S.S.)
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15
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Bayer TA. N-Truncated Aβ Starting at Position Four-Biochemical Features, Preclinical Models, and Potential as Drug Target in Alzheimer's Disease. Front Aging Neurosci 2021; 13:710579. [PMID: 34489680 PMCID: PMC8417877 DOI: 10.3389/fnagi.2021.710579] [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: 05/16/2021] [Accepted: 07/29/2021] [Indexed: 12/21/2022] Open
Abstract
The discussion of whether amyloid plaque Aβ is a valid drug target to fight Alzheimer’s disease (AD) has been a matter of scientific dispute for decades. This question can only be settled by successful clinical trials and the approval of disease-modifying drugs. However, many clinical trials with antibodies against different regions of the amyloid Aβ peptide have been discontinued, as they did not meet the clinical endpoints required. Recently, passive immunization of AD patients with Donanemab, an antibody directed against the N-terminus of pyroglutamate Aβ, showed beneficial effects in a phase II trial, supporting the concept that N-truncated Aβ is a relevant target for AD therapy. There is long-standing evidence that N-truncated Aβ variants are the main variants found in amyloid plaques besides full-length Aβ1–42, t, therefore their role in triggering AD pathology and as targets for drug development are of interest. While the contribution of pyroglutamate Aβ3–42 to AD pathology has been well studied in the past, the potential role of Aβ4–42 has been largely neglected. The present review will therefore focus on Aβ4–42 as a possible drug target based on human and mouse pathology, in vitro and in vivo toxicity, and anti-Aβ4-X therapeutic effects in preclinical models.
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Affiliation(s)
- Thomas A Bayer
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen (UMG), Georg-August-University, Göttingen, Germany
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Valverde A, Dunys J, Lorivel T, Debayle D, Gay AS, Caillava C, Chami M, Checler F. Dipeptidyl peptidase 4 contributes to Alzheimer's disease-like defects in a mouse model and is increased in sporadic Alzheimer's disease brains. J Biol Chem 2021; 297:100963. [PMID: 34265307 PMCID: PMC8334387 DOI: 10.1016/j.jbc.2021.100963] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 06/25/2021] [Accepted: 07/12/2021] [Indexed: 01/14/2023] Open
Abstract
The amyloid cascade hypothesis, which proposes a prominent role for full-length amyloid β peptides in Alzheimer's disease, is currently being questioned. In addition to full-length amyloid β peptide, several N-terminally truncated fragments of amyloid β peptide could well contribute to Alzheimer's disease setting and/or progression. Among them, pyroGlu3-amyloid β peptide appears to be one of the main components of early anatomical lesions in Alzheimer's disease-affected brains. Little is known about the proteolytic activities that could account for the N-terminal truncations of full-length amyloid β, but they appear as the rate-limiting enzymes yielding the Glu3-amyloid β peptide sequence that undergoes subsequent cyclization by glutaminyl cyclase, thereby yielding pyroGlu3-amyloid β. Here, we investigated the contribution of dipeptidyl peptidase 4 in Glu3-amyloid β peptide formation and the functional influence of its genetic depletion or pharmacological blockade on spine maturation as well as on pyroGlu3-amyloid β peptide and amyloid β 42-positive plaques and amyloid β 42 load in the triple transgenic Alzheimer's disease mouse model. Furthermore, we examined whether reduction of dipeptidyl peptidase 4 could rescue learning and memory deficits displayed by these mice. Our data establish that dipeptidyl peptidase 4 reduction alleviates anatomical, biochemical, and behavioral Alzheimer's disease-related defects. Furthermore, we demonstrate that dipeptidyl peptidase 4 activity is increased early in sporadic Alzheimer's disease brains. Thus, our data demonstrate that dipeptidyl peptidase 4 participates in pyroGlu3-amyloid β peptide formation and that targeting this peptidase could be considered as an alternative strategy to interfere with Alzheimer's disease progression.
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Affiliation(s)
- Audrey Valverde
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Julie Dunys
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Thomas Lorivel
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Delphine Debayle
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Anne-Sophie Gay
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Céline Caillava
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Mounia Chami
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France
| | - Frédéric Checler
- Team Labeled "Laboratory of Excellence (LABEX) Distalz", INSERM, CNRS, IPMC, Université Côte d'Azur, Sophia-Antipolis, Valbonne, France.
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17
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Abstract
A diverse range of N-terminally truncated and modified forms of amyloid-β (Aβ) oligomers have been discovered in Alzheimer’s disease brains, including the pyroglutamate-Aβ (AβpE3). AβpE3 species are shown to be more neurotoxic when compared with the full-length Aβ peptide. Findings visibly suggest that glutaminyl cyclase (QC) catalyzed the generation of cerebral AβpE3, and therapeutic effects are achieved by reducing its activity. In recent years, efforts to effectively develop QC inhibitors have been pursued worldwide. The inhibitory activity of current QC inhibitors is mainly triggered by zinc-binding groups that coordinate Zn2+ ion in the active site and other common features. Herein, we summarized the current state of discovery and evolution of QC inhibitors as a potential Alzheimer’s disease-modifying strategy.
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18
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Dunys J, Valverde A, Checler F. Are N- and C-terminally truncated Aβ species key pathological triggers in Alzheimer's disease? J Biol Chem 2018; 293:15419-15428. [PMID: 30143530 DOI: 10.1074/jbc.r118.003999] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The histopathology of Alzheimer's disease (AD) is characterized by neuronal loss, neurofibrillary tangles, and senile plaque formation. The latter results from an exacerbated production (familial AD cases) or altered degradation (sporadic cases) of 40/42-amino acid-long β-amyloid peptides (Aβ peptides) that are produced by sequential cleavages of Aβ precursor protein (βAPP) by β- and γ-secretases. The amyloid cascade hypothesis proposes a key role for the full-length Aβ42 and the Aβ40/42 ratio in AD etiology, in which soluble Aβ oligomers lead to neurotoxicity, tau hyperphosphorylation, aggregation, and, ultimately, cognitive defects. However, following this postulate, during the last decade, several clinical approaches aimed at decreasing full-length Aβ42 production or neutralizing it by immunotherapy have failed to reduce or even stabilize AD-related decline. Thus, the Aβ peptide (Aβ40/42)-centric hypothesis is probably a simplified view of a much more complex situation involving a multiplicity of APP fragments and Aβ catabolites. Indeed, biochemical analyses of AD brain deposits and fluids have unraveled an Aβ peptidome consisting of additional Aβ-related species. Such Aβ catabolites could be due to either primary enzymatic cleavages of βAPP or secondary processing of Aβ itself by exopeptidases. Here, we review the diversity of N- and C-terminally truncated Aβ peptides and their biosynthesis and outline their potential function/toxicity. We also highlight their potential as new pharmaceutical targets and biomarkers.
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Affiliation(s)
- Julie Dunys
- From the Université Côte d'Azur, INSERM, CNRS, IPMC, Team labeled "Laboratory of Excellence (LABEX) Distalz," 660 Route des Lucioles, Sophia-Antipolis, 06560 Valbonne, France
| | - Audrey Valverde
- From the Université Côte d'Azur, INSERM, CNRS, IPMC, Team labeled "Laboratory of Excellence (LABEX) Distalz," 660 Route des Lucioles, Sophia-Antipolis, 06560 Valbonne, France
| | - Frédéric Checler
- From the Université Côte d'Azur, INSERM, CNRS, IPMC, Team labeled "Laboratory of Excellence (LABEX) Distalz," 660 Route des Lucioles, Sophia-Antipolis, 06560 Valbonne, France
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Bernstein HG, Dobrowolny H, Keilhoff G, Steiner J. Dipeptidyl peptidase IV, which probably plays important roles in Alzheimer disease (AD) pathology, is upregulated in AD brain neurons and associates with amyloid plaques. Neurochem Int 2018; 114:55-57. [PMID: 29353063 DOI: 10.1016/j.neuint.2018.01.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/05/2018] [Accepted: 01/11/2018] [Indexed: 01/14/2023]
Abstract
There is evidence from in vitro experiments that dipeptidyl peptidase IV (DPP IV) might play role(s) in amyloid formation. However, nothing is known about the localization of the enzyme in brains of individuals with Alzheimer's disease. We herein show that in comparison to non-demented controls DPP IV is upregulated in AD brain neurons and occurs in multiple amyloid plaques.
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Affiliation(s)
- Hans-Gert Bernstein
- Department of Psychiatry, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
| | - Henrik Dobrowolny
- Department of Psychiatry, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
| | - Gerburg Keilhoff
- Institute of Biochemistry and Cell Biology, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
| | - Johann Steiner
- Department of Psychiatry, Otto v. Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany
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