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Li X, Quan M, Wei Y, Wang W, Xu L, Wang Q, Jia J. Critical thinking of Alzheimer's transgenic mouse model: current research and future perspective. SCIENCE CHINA. LIFE SCIENCES 2023; 66:2711-2754. [PMID: 37480469 DOI: 10.1007/s11427-022-2357-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 04/23/2023] [Indexed: 07/24/2023]
Abstract
Transgenic models are useful tools for studying the pathogenesis of and drug development for Alzheimer's Disease (AD). AD models are constructed usually using overexpression or knock-in of multiple pathogenic gene mutations from familial AD. Each transgenic model has its unique behavioral and pathological features. This review summarizes the research progress of transgenic mouse models, and their progress in the unique mechanism of amyloid-β oligomers, including the first transgenic mouse model built in China based on a single gene mutation (PSEN1 V97L) found in Chinese familial AD. We further summarized the preclinical findings of drugs using the models, and their future application in exploring the upstream mechanisms and multitarget drug development in AD.
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Affiliation(s)
- Xinyue Li
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Meina Quan
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
- National Medical Center for Neurological Diseases and National Clinical Research Center for Geriatric Diseases, Beijing, 100053, China
| | - Yiping Wei
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Wei Wang
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
- National Medical Center for Neurological Diseases and National Clinical Research Center for Geriatric Diseases, Beijing, 100053, China
| | - Lingzhi Xu
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Qi Wang
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
- National Medical Center for Neurological Diseases and National Clinical Research Center for Geriatric Diseases, Beijing, 100053, China
| | - Jianping Jia
- Innovation Center for Neurological Disorders and Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China.
- National Medical Center for Neurological Diseases and National Clinical Research Center for Geriatric Diseases, Beijing, 100053, China.
- Beijing Key Laboratory of Geriatric Cognitive Disorders, Beijing, 100053, China.
- Clinical Center for Neurodegenerative Disease and Memory Impairment, Capital Medical University, Beijing, 100053, China.
- Center of Alzheimer's Disease, Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100053, China.
- Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, 100053, China.
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Tambini MD, Yin T, Yesiltepe M, Breuillaud L, Zehntner SP, d'Abramo C, Giliberto L, D'Adamio L. Aβ43 levels determine the onset of pathological amyloid deposition. J Biol Chem 2023; 299:104868. [PMID: 37257821 PMCID: PMC10404620 DOI: 10.1016/j.jbc.2023.104868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 04/18/2023] [Accepted: 05/22/2023] [Indexed: 06/02/2023] Open
Abstract
About 2% of Alzheimer's disease (AD) cases have early onset (FAD) and are caused by mutations in either Presenilins (PSEN1/2) or amyloid-β precursor protein (APP). PSEN1/2 catalyze production of Aβ peptides of different length from APP. Aβ peptides are the major components of amyloid plaques, a pathological lesion that characterizes AD. Analysis of mechanisms by which PSEN1/2 and APP mutations affect Aβ peptide compositions lead to the implication of the absolute or relative increase in Aβ42 in amyloid-β plaques formation. Here, to elucidate the formation of pathogenic Aβ cocktails leading to amyloid pathology, we utilized FAD rat knock-in models carrying the Swedish APP (Apps allele) and the PSEN1 L435F (Psen1LF allele) mutations. To accommodate the differences in the pathogenicity of rodent and human Aβ, these rat models are genetically engineered to express human Aβ species as both the Swedish mutant allele and the WT rat allele (called Apph) have been humanized in the Aβ-coding region. Analysis of the eight possible FAD mutant permutations indicates that the CNS levels of Aβ43, rather than absolute or relative increases in Aβ42, determine the onset of pathological amyloid deposition in FAD knock-in rats. Notably, Aβ43 was found in amyloid plaques in late onset AD and mild cognitive impairment cases, suggesting that the mechanisms initiating amyloid pathology in FAD knock-in rat reflect disease mechanisms driving amyloid pathology in late onset AD. This study helps clarifying the molecular determinants initiating amyloid pathology and supports therapeutic interventions targeting Aβ43 in AD.
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Affiliation(s)
- Marc D Tambini
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
| | - Tao Yin
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
| | - Metin Yesiltepe
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, Newark, New Jersey, USA
| | | | | | - Cristina d'Abramo
- Litwin-Zucker Center for the Study of Alzheimer's Disease and Memory Disorders, Feinstein Institutes for Medical Research, Institute of Molecular Medicine, Northwell Health System, Manhasset, New York, USA
| | - Luca Giliberto
- Litwin-Zucker Center for the Study of Alzheimer's Disease and Memory Disorders, Feinstein Institutes for Medical Research, Institute of Molecular Medicine, Northwell Health System, Manhasset, New York, USA; Institute of Neurology and Neurosurgery, Northwell Health System, Manhasset, New York, USA
| | - Luciano D'Adamio
- Department of Pharmacology, Physiology & Neuroscience, New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, Newark, New Jersey, USA.
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Catania M, Marti A, Rossi G, Fioretti A, Boiocchi C, Ricci M, Gasparini F, Beltrami D, Crepaldi V, Redaelli V, Giaccone G, Fede GD. The novel I213S mutation in PSEN1 gene is located in a hotspot codon associated with familial early-onset Alzheimer's disease. Neurobiol Aging 2022; 112:191-196. [DOI: 10.1016/j.neurobiolaging.2022.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/26/2022] [Indexed: 11/28/2022]
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Akbar M, Shabbir A, Rehman K, Akash MSH, Shah MA. Neuroprotective potential of berberine in modulating Alzheimer's disease via multiple signaling pathways. J Food Biochem 2021; 45:e13936. [PMID: 34523148 DOI: 10.1111/jfbc.13936] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 09/01/2021] [Accepted: 09/02/2021] [Indexed: 12/22/2022]
Abstract
Berberine is one of the most important quinoline alkaloids, which has shown numerous pharmacological activities. There are pieces of evidence that berberine serves as a promising substance for treating Alzheimer's disease (AD). Recently, numerous studies on animal models have shown the neuroprotective role of berberine. AD is a complex disease having multiple pathological factors. Berberine restrains the deposition of amyloid plaques and neurofibrillary tangles. Substantial studies have demonstrated that berberine may also exhibit the protective effect against the risk factors associated with AD. This review illustrates the role of berberine in neuroinflammation, oxidative stress and its activity against acetylcholinesterase enzyme. It also focuses on the bioavailability and safety of berberine in AD. However, more investigations are required to explore the bioavailability and safety assessment of berberine and its new perspectives in limiting the AD-related pathogenesis and risk factors. PRACTICAL APPLICATIONS: Current therapeutic measures only provide symptomatic relief against AD by slowing memory loss, resolving thinking problems and behavioral issues. In recent past years, many biological actions and potential therapeutic applications have been observed by berberine particularly in neurological diseases. Berberine has been investigated by various researchers for its activity against AD. This review demonstrates a variety of mechanisms by which berberine imparts its neuroprotective roles and provides the possible mechanism of action of berberine by which it prevents the formation of neurofibrillary tangles and disaggregation of amyloid beta plaques in AD. It also focuses that berberine limits the neuroinflammation and oxidative stress in AD. Pre-clinical aspects of berberine against AD are also discussed. Eventually, a prospect is formulated that berberine might be a therapeutically significant agent for treating and preventing AD.
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Affiliation(s)
- Moazzama Akbar
- Department of Pharmaceutical Chemistry, Government College University, Faisalabad, Pakistan
| | - Anam Shabbir
- Department of Pharmaceutical Chemistry, Government College University, Faisalabad, Pakistan
| | - Kanwal Rehman
- Department of Pharmacy, University of Agriculture, Faisalabad, Pakistan
| | | | - Muhammad Ajmal Shah
- Department of Pharmacognosy, Government College University, Faisalabad, Pakistan
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Sato K, Watamura N, Fujioka R, Mihira N, Sekiguchi M, Nagata K, Ohshima T, Saito T, Saido TC, Sasaguri H. A third-generation mouse model of Alzheimer's disease shows early and increased cored plaque pathology composed of wild-type human amyloid β peptide. J Biol Chem 2021; 297:101004. [PMID: 34329683 PMCID: PMC8397900 DOI: 10.1016/j.jbc.2021.101004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/15/2021] [Accepted: 07/22/2021] [Indexed: 01/22/2023] Open
Abstract
We previously developed single App knock-in mouse models of Alzheimer's disease (AD) harboring the Swedish and Beyreuther/Iberian mutations with or without the Arctic mutation (AppNL-G-F and AppNL-F mice, respectively). These models showed Aβ pathology, neuroinflammation, and cognitive impairment in an age-dependent manner. The former model exhibits extensive pathology as early as 6 months, but is unsuitable for investigating Aβ metabolism and clearance because the Arctic mutation renders Aβ resistant to proteolytic degradation and prone to aggregation. In particular, it is inapplicable to preclinical immunotherapy studies due to its discrete affinity for anti-Aβ antibodies. The latter model may take as long as 18 months for the pathology to become prominent, which leaves an unfulfilled need for an Alzheimer's disease animal model that is both swift to show pathology and useful for antibody therapy. We thus utilized mutant Psen1 knock-in mice into which a pathogenic mutation (P117L) had been introduced to generate a new model that exhibits early deposition of wild-type human Aβ by crossbreeding the AppNL-F line with the Psen1P117L/WT line. We show that the effects of the pathogenic mutations in the App and Psen1 genes are additive or synergistic. This new third-generation mouse model showed more cored plaque pathology and neuroinflammation than AppNL-G-F mice and will help accelerate the development of disease-modifying therapies to treat preclinical AD.
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Affiliation(s)
- Kaori Sato
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan; Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku, Tokyo, Japan
| | - Naoto Watamura
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Ryo Fujioka
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Naomi Mihira
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Misaki Sekiguchi
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Kenichi Nagata
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Toshio Ohshima
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku, Tokyo, Japan
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan.
| | - Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan.
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Singh AK, Singh SK, Nandi MK, Mishra G, Maurya A, Rai A, Rai GK, Awasthi R, Sharma B, Kulkarni GT. Berberine: A Plant-derived Alkaloid with Therapeutic Potential to Combat Alzheimer's disease. Cent Nerv Syst Agents Med Chem 2020; 19:154-170. [PMID: 31429696 DOI: 10.2174/1871524919666190820160053] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/29/2019] [Accepted: 08/06/2019] [Indexed: 12/20/2022]
Abstract
Berberine (a protoberberine isoquinoline alkaloid) has shown promising pharmacological activities, including analgesic, anti-inflammatory, anticancer, antidiabetic, anti-hyperlipidemic, cardioprotective, memory enhancement, antidepressant, antioxidant, anti-nociceptive, antimicrobial, anti- HIV and cholesterol-lowering effects. It is used in the treatment of the neurodegenerative disorder. It has strong evidence to serve as a potent phytoconstituent in the treatment of various neurodegenerative disorders such as AD. It limits the extracellular amyloid plaques and intracellular neurofibrillary tangles. It has also lipid-glucose lowering ability, hence can be used as a protective agent in atherosclerosis and AD. However, more detailed investigations along with safety assessment of berberine are warranted to clarify its role in limiting various risk factors and AD-related pathologies. This review highlights the pharmacological basis to control oxidative stress, neuroinflammation and protective effect of berberine in AD, which will benefit to the biological scientists in understanding and exploring the new vistas of berberine in combating Alzheimer's disease.
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Affiliation(s)
- Anurag K Singh
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India
| | - Santosh K Singh
- Centre of Experimental Medicine & Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India
| | - Manmath K Nandi
- Institute of Medical Sciences, Faculty of Ayurveda, Department of medicinal chemistry, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Gaurav Mishra
- Institute of Medical Sciences, Faculty of Ayurveda, Department of medicinal chemistry, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Anand Maurya
- Institute of Medical Sciences, Faculty of Ayurveda, Department of medicinal chemistry, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India
| | - Arati Rai
- Hygia Institute of Pharmaceutical Education & Research, Lucknow-226020, Uttar Pradesh, India
| | - Gopal K Rai
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi-221005, Uttar Pradesh, India
| | - Rajendra Awasthi
- Department of Pharmaceutics, Amity Institute of Pharmacy, Amity University Uttar Pradesh, Sec 125, Noida, 201303, Uttar Pradesh, India
| | - Bhupesh Sharma
- Department of Pharmacology, Amity Institute of Pharmacy, Amity University Uttar Pradesh, Sec 125, Noida, 201303, Uttar Pradesh, India
| | - Giriraj T Kulkarni
- Department of Pharmaceutics, Amity Institute of Pharmacy, Amity University Uttar Pradesh, Sec 125, Noida, 201303, Uttar Pradesh, India
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Maia MA, Sousa E. BACE-1 and γ-Secretase as Therapeutic Targets for Alzheimer's Disease. Pharmaceuticals (Basel) 2019; 12:ph12010041. [PMID: 30893882 PMCID: PMC6469197 DOI: 10.3390/ph12010041] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/13/2019] [Accepted: 03/15/2019] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is a growing global health concern with a massive impact on affected individuals and society. Despite the considerable advances achieved in the understanding of AD pathogenesis, researchers have not been successful in fully identifying the mechanisms involved in disease progression. The amyloid hypothesis, currently the prevalent theory for AD, defends the deposition of β-amyloid protein (Aβ) aggregates as the trigger of a series of events leading to neuronal dysfunction and dementia. Hence, several research and development (R&D) programs have been led by the pharmaceutical industry in an effort to discover effective and safety anti-amyloid agents as disease modifying agents for AD. Among 19 drug candidates identified in the AD pipeline, nine have their mechanism of action centered in the activity of β or γ-secretase proteases, covering almost 50% of the identified agents. These drug candidates must fulfill the general rigid prerequisites for a drug aimed for central nervous system (CNS) penetration and selectivity toward different aspartyl proteases. This review presents the classes of γ-secretase and beta-site APP cleaving enzyme 1 (BACE-1) inhibitors under development, highlighting their structure-activity relationship, among other physical-chemistry aspects important for the successful development of new anti-AD pharmacological agents.
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Affiliation(s)
- Miguel A Maia
- Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
| | - Emília Sousa
- Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal.
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Tang N, Kepp KP. Aβ42/Aβ40 Ratios of Presenilin 1 Mutations Correlate with Clinical Onset of Alzheimer’s Disease. J Alzheimers Dis 2018; 66:939-945. [DOI: 10.3233/jad-180829] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Ning Tang
- Technical University of Denmark, DTU Chemistry, Kgs. Lyngby, Denmark
| | - Kasper P. Kepp
- Technical University of Denmark, DTU Chemistry, Kgs. Lyngby, Denmark
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Sasaguri H, Nagata K, Sekiguchi M, Fujioka R, Matsuba Y, Hashimoto S, Sato K, Kurup D, Yokota T, Saido TC. Introduction of pathogenic mutations into the mouse Psen1 gene by Base Editor and Target-AID. Nat Commun 2018; 9:2892. [PMID: 30042426 PMCID: PMC6057936 DOI: 10.1038/s41467-018-05262-w] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Accepted: 06/22/2018] [Indexed: 01/26/2023] Open
Abstract
Base Editor (BE) and Target-AID (activation-induced cytidine deaminase) are engineered genome-editing proteins composed of Cas9 and cytidine deaminases. These base-editing tools convert C:G base pairs to T:A at target sites. Here, we inject either BE or Target-AID mRNA together with identical single-guide RNAs (sgRNAs) into mouse zygotes, and compare the base-editing efficiencies of the two distinct tools in vivo. BE consistently show higher base-editing efficiency (10.0–62.8%) compared to that of Target-AID (3.4–29.8%). However, unexpected base substitutions and insertion/deletion formations are also more frequently observed in BE-injected mice or zygotes. We are able to generate multiple mouse lines harboring point mutations in the mouse presenilin 1 (Psen1) gene by injection of BE or Target-AID. These results demonstrate that BE and Target-AID are highly useful tools to generate mice harboring pathogenic point mutations and to analyze the functional consequences of the mutations in vivo. CRISPR-guided cytidine deaminases, including BE3 (Base Editor 3) and Target-AID (activation-induced cytidine deaminase), can covert C:G base pairs to T:A at target site. Here, the authors generate missense mutations of mouse Psen1 gene and find BE3 has higher editing efficiency than Target-AID.
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Affiliation(s)
- Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan. .,Department of Neurology and Neurological Science, Graduate School of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, 113-8510, Japan.
| | - Kenichi Nagata
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan
| | - Misaki Sekiguchi
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan
| | - Ryo Fujioka
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan
| | - Yukio Matsuba
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan
| | - Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan
| | - Kaori Sato
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan
| | - Deepika Kurup
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Takanori Yokota
- Department of Neurology and Neurological Science, Graduate School of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, 351-0198, Japan.
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Veugelen S, Saito T, Saido TC, Chávez-Gutiérrez L, De Strooper B. Familial Alzheimer's Disease Mutations in Presenilin Generate Amyloidogenic Aβ Peptide Seeds. Neuron 2017; 90:410-6. [PMID: 27100199 DOI: 10.1016/j.neuron.2016.03.010] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 12/24/2015] [Accepted: 03/10/2016] [Indexed: 01/15/2023]
Abstract
Recently it was proposed that the familial Alzheimer's disease (FAD) causing presenilin (PSEN) mutations PSEN1-L435F and PSEN1-C410Y do not support the generation of Aβ-peptides from the amyloid precursor protein (APP). This challenges the amyloid hypothesis and disagrees with previous work showing that PSEN1 FAD causing mutations generate invariably long Aβ and seed amyloid. We contrast here the proteolytic activities of these mutant PSEN alleles with the complete loss-of-function PSEN1-D257A allele. We find residual carboxy- and endo-peptidase γ-secretase activities, similar to the formerly characterized PSEN1-R278I. We conclude that the PSEN1-L435F and -C410Y mutations are extreme examples of the previously proposed "dysfunction" of γ-secretase that characterizes FAD-associated PSEN. This Matters Arising paper is in response to Xia et al. (2015), published in Neuron. See also the response by Xia et al. (2016), published in this issue.
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Affiliation(s)
- Sarah Veugelen
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium; Center for Human Genetics, and Leuven Institute for Neurodegenerative Diseases (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Lucía Chávez-Gutiérrez
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium; Center for Human Genetics, and Leuven Institute for Neurodegenerative Diseases (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium.
| | - Bart De Strooper
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium; Center for Human Genetics, and Leuven Institute for Neurodegenerative Diseases (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium; Institute of Neurology, University College London, London, WC1N 3BG, UK.
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Bursavich MG, Harrison BA, Acharya R, Costa DE, Freeman EA, Hodgdon HE, Hrdlicka LA, Jin H, Kapadnis S, Moffit JS, Murphy DA, Nolan S, Patzke H, Tang C, Wen M, Koenig G, Blain JF, Burnett DA. Design, Synthesis, and Evaluation of a Novel Series of Oxadiazine Gamma Secretase Modulators for Familial Alzheimer’s Disease. J Med Chem 2017; 60:2383-2400. [DOI: 10.1021/acs.jmedchem.6b01620] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Matthew G. Bursavich
- FORUM Pharmaceuticals, 225 Second Avenue, Waltham, Massachusetts 02451, United States
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Almdahl IS, Lauridsen C, Selnes P, Kalheim LF, Coello C, Gajdzik B, Møller I, Wettergreen M, Grambaite R, Bjørnerud A, Bråthen G, Sando SB, White LR, Fladby T. Cerebrospinal Fluid Levels of Amyloid Beta 1-43 Mirror 1-42 in Relation to Imaging Biomarkers of Alzheimer's Disease. Front Aging Neurosci 2017; 9:9. [PMID: 28223932 PMCID: PMC5293760 DOI: 10.3389/fnagi.2017.00009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/12/2017] [Indexed: 11/24/2022] Open
Abstract
Introduction: Amyloid beta 1-43 (Aβ43), with its additional C-terminal threonine residue, is hypothesized to play a role in early Alzheimer’s disease pathology possibly different from that of amyloid beta 1-42 (Aβ42). Cerebrospinal fluid (CSF) Aβ43 has been suggested as a potential novel biomarker for predicting conversion from mild cognitive impairment (MCI) to dementia in Alzheimer’s disease. However, the relationship between CSF Aβ43 and established imaging biomarkers of Alzheimer’s disease has never been assessed. Materials and Methods: In this observational study, CSF Aβ43 was measured with ELISA in 89 subjects; 34 with subjective cognitive decline (SCD), 51 with MCI, and four with resolution of previous cognitive complaints. All subjects underwent structural MRI; 40 subjects on a 3T and 50 on a 1.5T scanner. Forty subjects, including 24 with SCD and 12 with MCI, underwent 18F-Flutemetamol PET. Seventy-eight subjects were assessed with 18F-fluorodeoxyglucose PET (21 SCD/7 MCI and 11 SCD/39 MCI on two different scanners). Ten subjects with SCD and 39 with MCI also underwent diffusion tensor imaging. Results: Cerebrospinal fluid Aβ43 was both alone and together with p-tau a significant predictor of the distinction between SCD and MCI. There was a marked difference in CSF Aβ43 between subjects with 18F-Flutemetamol PET scans visually interpreted as negative (37 pg/ml, n = 27) and positive (15 pg/ml, n = 9), p < 0.001. Both CSF Aβ43 and Aβ42 were negatively correlated with standardized uptake value ratios for all analyzed regions; CSF Aβ43 average rho -0.73, Aβ42 -0.74. Both CSF Aβ peptides correlated significantly with hippocampal volume, inferior parietal and frontal cortical thickness and axial diffusivity in the corticospinal tract. There was a trend toward CSF Aβ42 being better correlated with cortical glucose metabolism. None of the studied correlations between CSF Aβ43/42 and imaging biomarkers were significantly different for the two Aβ peptides when controlling for multiple testing. Conclusion: Cerebrospinal fluid Aβ43 appears to be strongly correlated with cerebral amyloid deposits in the same way as Aβ42, even in non-demented patients with only subjective cognitive complaints. Regarding imaging biomarkers, there is no evidence from the present study that CSF Aβ43 performs better than the classical CSF biomarker Aβ42 for distinguishing SCD and MCI.
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Affiliation(s)
- Ina S Almdahl
- Division of Medicine and Laboratory Sciences, Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway; Department of Neurology, Akershus University HospitalLørenskog, Norway
| | - Camilla Lauridsen
- Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and Technology Trondheim, Norway
| | - Per Selnes
- Division of Medicine and Laboratory Sciences, Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway; Department of Neurology, Akershus University HospitalLørenskog, Norway
| | - Lisa F Kalheim
- Division of Medicine and Laboratory Sciences, Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway; Department of Neurology, Akershus University HospitalLørenskog, Norway
| | - Christopher Coello
- Preclinical PET/CT, Institute of Basic Medical Sciences, University of Oslo Oslo, Norway
| | | | - Ina Møller
- Department of Neurology and Clinical Neurophysiology, University Hospital of Trondheim Trondheim, Norway
| | - Marianne Wettergreen
- Department of Neurology, Akershus University HospitalLørenskog, Norway; Department of Clinical Molecular Biology (EpiGen), Institute of Clinical Medicine, University of Oslo - Akershus University HospitalLørenskog, Norway
| | - Ramune Grambaite
- Department of Neurology, Akershus University Hospital Lørenskog, Norway
| | - Atle Bjørnerud
- The Intervention Centre, Oslo University Hospital Oslo, Norway
| | - Geir Bråthen
- Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and TechnologyTrondheim, Norway; Department of Neurology and Clinical Neurophysiology, University Hospital of TrondheimTrondheim, Norway
| | - Sigrid B Sando
- Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and TechnologyTrondheim, Norway; Department of Neurology and Clinical Neurophysiology, University Hospital of TrondheimTrondheim, Norway
| | - Linda R White
- Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and TechnologyTrondheim, Norway; Department of Neurology and Clinical Neurophysiology, University Hospital of TrondheimTrondheim, Norway
| | - Tormod Fladby
- Division of Medicine and Laboratory Sciences, Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway; Department of Neurology, Akershus University HospitalLørenskog, Norway
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13
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Cicvaric A, Yang J, Krieger S, Khan D, Kim EJ, Dominguez-Rodriguez M, Cabatic M, Molz B, Acevedo Aguilar JP, Milicevic R, Smani T, Breuss JM, Kerjaschki D, Pollak DD, Uhrin P, Monje FJ. The brain-tumor related protein podoplanin regulates synaptic plasticity and hippocampus-dependent learning and memory. Ann Med 2016; 48:652-668. [PMID: 27558977 PMCID: PMC5125287 DOI: 10.1080/07853890.2016.1219455] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/14/2016] [Accepted: 07/25/2016] [Indexed: 01/15/2023] Open
Abstract
INTRODUCTION Podoplanin is a cell-surface glycoprotein constitutively expressed in the brain and implicated in human brain tumorigenesis. The intrinsic function of podoplanin in brain neurons remains however uncharacterized. MATERIALS AND METHODS Using an established podoplanin-knockout mouse model and electrophysiological, biochemical, and behavioral approaches, we investigated the brain neuronal role of podoplanin. RESULTS Ex-vivo electrophysiology showed that podoplanin deletion impairs dentate gyrus synaptic strengthening. In vivo, podoplanin deletion selectively impaired hippocampus-dependent spatial learning and memory without affecting amygdala-dependent cued fear conditioning. In vitro, neuronal overexpression of podoplanin promoted synaptic activity and neuritic outgrowth whereas podoplanin-deficient neurons exhibited stunted outgrowth and lower levels of p-Ezrin, TrkA, and CREB in response to nerve growth factor (NGF). Surface Plasmon Resonance data further indicated a physical interaction between podoplanin and NGF. DISCUSSION This work proposes podoplanin as a novel component of the neuronal machinery underlying neuritogenesis, synaptic plasticity, and hippocampus-dependent memory functions. The existence of a relevant cross-talk between podoplanin and the NGF/TrkA signaling pathway is also for the first time proposed here, thus providing a novel molecular complex as a target for future multidisciplinary studies of the brain function in the physiology and the pathology. Key messages Podoplanin, a protein linked to the promotion of human brain tumors, is required in vivo for proper hippocampus-dependent learning and memory functions. Deletion of podoplanin selectively impairs activity-dependent synaptic strengthening at the neurogenic dentate-gyrus and hampers neuritogenesis and phospho Ezrin, TrkA and CREB protein levels upon NGF stimulation. Surface plasmon resonance data indicates a physical interaction between podoplanin and NGF. On these grounds, a relevant cross-talk between podoplanin and NGF as well as a role for podoplanin in plasticity-related brain neuronal functions is here proposed.
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Affiliation(s)
- Ana Cicvaric
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Jiaye Yang
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Sigurd Krieger
- Clinical Institute of Pathology, Medical University of Vienna,
Vienna,
Austria
| | - Deeba Khan
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Eun-Jung Kim
- Paik Institute for Clinical Research, Inje University College of Medicine,
Busan,
Republic of Korea
| | - Manuel Dominguez-Rodriguez
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Maureen Cabatic
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Barbara Molz
- Psychology University of York,
Heslington York,
UK
| | - Juan Pablo Acevedo Aguilar
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Radoslav Milicevic
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Tarik Smani
- Grupo de Fisiopatología Cardiovascular, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla,
Seville,
Spain
| | - Johannes M. Breuss
- Department of Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Dontscho Kerjaschki
- Clinical Institute of Pathology, Medical University of Vienna,
Vienna,
Austria
| | - Daniela D. Pollak
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Pavel Uhrin
- Department of Vascular Biology and Thrombosis Research, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
| | - Francisco J. Monje
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna,
Vienna,
Austria
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14
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Blain JF, Bursavich MG, Freeman EA, Hrdlicka LA, Hodgdon HE, Chen T, Costa DE, Harrison BA, Kapadnis S, Murphy DA, Nolan S, Tu Z, Tang C, Burnett DA, Patzke H, Koenig G. Characterization of FRM-36143 as a new γ-secretase modulator for the potential treatment of familial Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2016; 8:34. [PMID: 27572246 PMCID: PMC5004293 DOI: 10.1186/s13195-016-0199-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/18/2016] [Indexed: 01/01/2023]
Abstract
Background Familial Alzheimer’s disease (FAD) is caused by mutations in the amyloid precursor protein (APP) or presenilin (PS). Most PS mutations, which account for the majority of FAD cases, lead to an increased ratio of longer to shorter forms of the amyloid beta (Aβ) peptide. The therapeutic rationale of γ-secretase modulators (GSMs) for Alzheimer’s disease is based on this genetic evidence as well as on enzyme kinetics measurements showing changes in the processivity of the γ-secretase complex. This analysis suggests that GSMs could potentially offset some of the effects of PS mutations on APP processing, thereby addressing the root cause of early onset FAD. Unfortunately, the field has generated few, if any, molecules with good central nervous system (CNS) drug-like properties to enable proof-of-mechanism studies. Method We characterized the novel GSM FRM-36143 using multiple cellular assays to determine its in vitro potency and off-target activity as well as its potential to reverse the effect of PS mutations. We also tested its efficacy in vivo in wild-type mice and rats. Results FRM-36143 has much improved CNS drug-like properties compared to published GSMs. It has an in vitro EC50 for Aβ42 of 35 nM in H4 cells, can reduce Aβ42 to 58 % of the baseline in rat cerebrospinal fluid, and also increases the non-amyloidogenic peptides Aβ37 and Aβ38. It does not inhibit Notch processing, nor does it inhibit 24-dehydrocholesterol reductase (DHCR24) activity. Most interestingly, it can reverse the effects of presenilin mutations on APP processing in vitro. Conclusions FRM-36143 possesses all the characteristics of a GSM in terms of Aβ modulation Because FRM-36143 was able to reverse the effect of PS mutations, we suggest that targeting patients with this genetic defect would be the best approach at testing the efficacy of a GSM in the clinic. While the amyloid hypothesis is still being tested with β-site APP-cleaving enzyme inhibitors and monoclonal antibodies in sporadic AD, we believe it is not a hypothesis for FAD. Since GSMs can correct the molecular defect caused by PS mutations, they have the promise to provide benefits to the patients when treated early enough in the course of the disease.
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Affiliation(s)
| | | | - Emily A Freeman
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Lori A Hrdlicka
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | | | - Ting Chen
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Don E Costa
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Bryce A Harrison
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | | | - Deirdre A Murphy
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Scott Nolan
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Zhiming Tu
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Cuyue Tang
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Duane A Burnett
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Holger Patzke
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
| | - Gerhard Koenig
- FORUM Pharmaceuticals Inc, 225 2nd Avenue, Waltham, MA, 02451, USA
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15
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Bursavich MG, Harrison BA, Blain JF. Gamma Secretase Modulators: New Alzheimer's Drugs on the Horizon? J Med Chem 2016; 59:7389-409. [PMID: 27007185 DOI: 10.1021/acs.jmedchem.5b01960] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The rapidly aging population desperately requires new therapies for Alzheimer's disease. Despite years of pharmaceutical research, limited clinical success has been realized, with several failed disease modification therapies in recent years. On the basis of compelling genetic evidence, the pharmaceutical industry has put a large emphasis on brain beta amyloid (Aβ) either through its removal via antibodies or by targeting the proteases responsible for its production. In this Perspective, we focus on the development of small molecules that improve the activity of one such protease, gamma secretase, through an allosteric binding site to preferentially increase the concentration of the shorter non-amyloidogenic Aβ species. After a few early failures due to poor drug-like properties, the industry is now on the cusp of delivering gamma secretase modulators for clinical proof-of-mechanism studies that combine potency and efficacy with improved drug-like properties such as lower cLogP, high central nervous system multiparameter optimization scores, and high sp(3) character.
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Affiliation(s)
- Matthew G Bursavich
- FORUM Pharmaceuticals , 225 Second Avenue, Waltham, Massachusetts 02451, United States
| | - Bryce A Harrison
- FORUM Pharmaceuticals , 225 Second Avenue, Waltham, Massachusetts 02451, United States
| | - Jean-François Blain
- FORUM Pharmaceuticals , 225 Second Avenue, Waltham, Massachusetts 02451, United States
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16
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Abstract
Berberine, an important protoberberine isoquinoline alkaloid, has several pharmacological activities, including antimicrobial, glucose- and cholesterol-lowering, antitumoral, and immunomodulatory properties. Substantial studies suggest that berberine may be beneficial to Alzheimer's disease (AD) by limiting the pathogenesis of extracellular amyloid plaques and intracellular neurofibrillary tangles. Increasing evidence has indicated that berberine exerts a protective role in atherosclerosis related to lipid- and glucose-lowering properties, implicating that berberine has the potential to inhibit these risk factors for AD. This review also attempts to discuss the pharmacological basis through which berberine may retard oxidative stress and neuroinflammation to exhibit its protective role in AD. Accordingly, berberine might be considered a potential therapeutic approach to prevent or delay the process of AD. However, more detailed investigations along with a safety assessment of berberine are warranted to clarify the role of berberine in limiting these risk factors and AD-related pathologies.
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Affiliation(s)
- Zhiyou Cai
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan Renmin Hospital, Shiyan, Hubei Province
| | - Chuanling Wang
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan Renmin Hospital, Shiyan, Hubei Province
| | - Wenming Yang
- Department of Neurology, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, Anhui Province, People's Republic of China
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17
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C-Terminal Threonine Reduces Aβ43 Amyloidogenicity Compared with Aβ42. J Mol Biol 2015; 428:274-291. [PMID: 26122432 DOI: 10.1016/j.jmb.2015.06.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 04/19/2015] [Accepted: 06/17/2015] [Indexed: 12/21/2022]
Abstract
Aβ43, a product of the proteolysis of the amyloid precursor protein APP, is related to Aβ42 by an additional Thr residue at the C-terminus. Aβ43 is typically generated at low levels compared with the predominant Aβ42 and Aβ40 forms, but it has been suggested that this longer peptide might have an impact on amyloid-β aggregation and Alzheimer's disease that is out of proportion to its brain content. Here, we report that both Aβ42 and Aβ43 spontaneously aggregate into mature amyloid fibrils via sequential appearance of the same series of oligomeric and protofibrillar intermediates, the earliest of which appears to lack β-structure. In spite of the additional β-branched amino acid at the C-terminus, Aβ43 fibrils have fewer strong backbone H-bonds than Aβ42 fibrils, some of which are lost at the C-terminus. In contrast to previous reports, we found that Aβ43 spontaneously aggregates more slowly than Aβ42. In addition, Aβ43 fibrils are very inefficient at seeding Aβ42 amyloid formation, even though Aβ42 fibrils efficiently seed amyloid formation by Aβ43 monomers. Finally, mixtures of Aβ42 and Aβ43 aggregate more slowly than Aβ42 alone. Both in this Aβ42/Aβ43 co-aggregation reaction and in cross-seeding by Aβ42 fibrils, the structure of the Aβ43 in the product fibrils is influenced by the presence of Aβ42. The results provide new details of amyloid structure and assembly pathways, an example of structural plasticity in prion-like replication, and data showing that low levels of Aβ43 in the brain are unlikely to favorably impact the aggregation of Aβ42.
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18
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Morishima-Kawashima M. Molecular mechanism of the intramembrane cleavage of the β-carboxyl terminal fragment of amyloid precursor protein by γ-secretase. Front Physiol 2014; 5:463. [PMID: 25505888 PMCID: PMC4245903 DOI: 10.3389/fphys.2014.00463] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 11/11/2014] [Indexed: 01/31/2023] Open
Abstract
Amyloid β-protein (Aβ) plays a central role in the pathogenesis of Alzheimer's disease, the most common age-associated neurodegenerative disorder. Aβ is generated through intramembrane proteolysis of the β-carboxyl terminal fragment (βCTF) of β-amyloid precursor protein (APP) by γ-secretase. The initial cleavage by γ-secretase occurs in the membrane/cytoplasm boundary of the βCTF, liberating the APP intracellular domain (AICD). The remaining βCTFs, which are truncated at the C-terminus (longer Aβs), are then cropped sequentially in a stepwise manner, predominantly at three residue intervals, to generate Aβ. There are two major Aβ product lines which generate Aβ40 and Aβ42 with concomitant release of three and two tripeptides, respectively. Additionally, many alternative cleavages occur, releasing peptides with three to six residues. These modulate the Aβ product lines and define the species and quantity of Aβ generated. Here, we review our current understanding of the intramembrane cleavage of the βCTF by γ-secretase, which may contribute to the future goal of developing an efficient therapeutic strategy for Alzheimer's disease.
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Affiliation(s)
- Maho Morishima-Kawashima
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University Sapporo, Japan
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19
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Fernandez MA, Klutkowski JA, Freret T, Wolfe MS. Alzheimer presenilin-1 mutations dramatically reduce trimming of long amyloid β-peptides (Aβ) by γ-secretase to increase 42-to-40-residue Aβ. J Biol Chem 2014; 289:31043-52. [PMID: 25239621 DOI: 10.1074/jbc.m114.581165] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The presenilin-containing γ-secretase complex produces the amyloid β-peptide (Aβ) through intramembrane proteolysis, and >100 presenilin mutations are associated with familial early-onset Alzheimer disease (AD). The question of whether these mutations result in AD through a gain or a loss of function remains highly controversial. Mutations in presenilins increase ratios of 42- to 40-residue Aβ critical to pathogenesis, but other Aβs of 38-49 residues are also formed by γ-secretase. Evidence in cells suggests the protease first cleaves substrate within the transmembrane domain at the ϵ site to form 48- or 49-residue Aβ. Subsequent cleavage almost every three residues from the C terminus is thought to occur along two pathways toward shorter secreted forms of Aβ: Aβ49 → Aβ46 → Aβ43 → Aβ40 and Aβ48 → Aβ45 → Aβ42 → Aβ38. Here we show that the addition of synthetic long Aβ peptides (Aβ45-49) directly into purified preparations of γ-secretase leads to the formation of Aβ40 and Aβ42 whether the protease complex is detergent-solubilized or reconstituted into lipid vesicles, and the ratios of products Aβ42 to Aβ40 follow a pattern consistent with the dual-pathway hypothesis. Kinetic analysis of five different AD-causing mutations in presenilin-1 revealed that all result in drastic reduction of normal carboxypeptidase function. Altered trimming of long Aβ peptides to Aβ40 and Aβ42 by mutant proteases occurs at multiple levels, independent of the effects on initial endoproteolysis at the ϵ site, all conspiring to increase the critical Aβ42/Aβ40 ratio implicated in AD pathogenesis. Taken together, these results suggest that specific reduction of carboxypeptidase function of γ-secretase leads to the gain of toxic Aβ42/Aβ40.
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Affiliation(s)
- Marty A Fernandez
- From the Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Julia A Klutkowski
- From the Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Taylor Freret
- From the Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Michael S Wolfe
- From the Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
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20
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Sandebring A, Welander H, Winblad B, Graff C, Tjernberg LO. The pathogenic aβ43 is enriched in familial and sporadic Alzheimer disease. PLoS One 2013; 8:e55847. [PMID: 23409063 PMCID: PMC3569467 DOI: 10.1371/journal.pone.0055847] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 01/04/2013] [Indexed: 11/18/2022] Open
Abstract
The amyloid-cascade hypothesis posits that the role of amyloid β-peptide (Aβ) in Alzheimer disease (AD) involves polymerization into structures that eventually are deposited as amyloid plaques. During this process, neurotoxic oligomers are formed that induce synaptic loss and neuronal death. Several different isoforms of Aβ are produced, of which the 40 and 42 residue variants (Aβ40 and Aβ42) are the most common. Aβ42 has a strong tendency to form neurotoxic aggregates and is involved in AD pathogenesis. Longer Aβ isoforms, like the less studied Aβ43, are gaining attention for their higher propensity to aggregate into neurotoxic oligomers. To further investigate Aβ43 in AD, we conducted a quantitative study on Aβ43 levels in human brain. We homogenized human brain tissue and prepared fractions of various solubility; tris buffered saline (TBS), sodium dodecyl sulfate (SDS) and formic acid (FA). Levels of Aβ43, as well as Aβ40 and Aβ42, were quantified using ELISA. We compared quantitative data showing Aβ levels in occipital and frontal cortex from sporadic (SAD) and familial (FAD) AD cases, as well as non-demented (ND) controls. Results showed Aβ43 present in each fraction from the SAD and FAD cases, while its level was lower than the detection limit in the majority of the ND-cases. Aβ42 and Aβ43 were enriched in the less soluble fractions (SDS and FA) of SAD and FAD cases in both occipital and frontal cortex. Thus, although the total levels of Aβ43 in human brain are low compared to Aβ40 and Aβ42, we suggest that Aβ43 could initiate the formation of oligomers and amyloid plaques and thereby be crucial to AD pathogenesis.
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Affiliation(s)
- Anna Sandebring
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, KI-Alzheimer’s Disease Research center (KI-ADRC), Huddinge, Sweden
| | - Hedvig Welander
- Department of Public Health/Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Bengt Winblad
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, KI-Alzheimer’s Disease Research center (KI-ADRC), Huddinge, Sweden
| | - Caroline Graff
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, KI-Alzheimer’s Disease Research center (KI-ADRC), Huddinge, Sweden
| | - Lars O. Tjernberg
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, KI-Alzheimer’s Disease Research center (KI-ADRC), Huddinge, Sweden
- * E-mail:
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21
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APP mutations in the Aβ coding region are associated with abundant cerebral deposition of Aβ38. Acta Neuropathol 2012; 124:809-21. [PMID: 23143229 DOI: 10.1007/s00401-012-1061-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 10/24/2012] [Accepted: 10/26/2012] [Indexed: 12/19/2022]
Abstract
Aβ is the main component of amyloid deposits in Alzheimer disease (AD) and its aggregation into oligomers, protofibrils and fibrils is considered a seminal event in the pathogenesis of AD. Aβ with C-terminus at residue 42 is the most abundant species in parenchymal deposits, whereas Aβ with C-terminus at residue 40 predominates in the amyloid of the walls of large vessels. Aβ peptides with other C-termini have not yet been thoroughly investigated. We analysed Aβ38 in the brains of patients with Aβ deposition linked to sporadic and familial AD, hereditary cerebral haemorrhage with amyloidosis, or Down syndrome. Immunohistochemistry, confocal microscopy, immunoelectron microscopy, immunoprecipitation and the electrophoresis separation of low molecular weight aggregates revealed that Aβ38 accumulates consistently in the brains of patients carrying APP mutations in the Aβ coding region, but was not detected in the patients with APP mutations outside the Aβ domain, in the patients with presenilin mutations or in subjects with Down syndrome. In the patients with sporadic AD, Aβ38 was absent in the senile plaques, but it was detected only in the vessel walls of a small subset of patients with severe cerebral amyloid angiopathy. Our results suggest that APP mutations in the Aβ coding region favour Aβ38 accumulation in the brain and that the molecular mechanisms of Aβ deposition in these patients may be different from those active in patients with familial AD associated with other genetic defects and sporadic AD.
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22
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Weggen S, Beher D. Molecular consequences of amyloid precursor protein and presenilin mutations causing autosomal-dominant Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2012; 4:9. [PMID: 22494386 PMCID: PMC3334542 DOI: 10.1186/alzrt107] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Mutations in both the amyloid precursor protein (APP) and the presenilin (PSEN) genes cause familial Alzheimer's disease (FAD) with autosomal dominant inheritance and early onset of disease. The clinical course and neuropathology of FAD and sporadic Alzheimer's disease are highly similar, and patients with FAD constitute a unique population in which to conduct treatment and, in particular, prevention trials with novel pharmaceutical entities. It is critical, therefore, to exactly defi ne the molecular consequences of APP and PSEN FAD mutations. Both APP and PSEN mutations drive amyloidosis in FAD patients through changes in the brain metabolism of amyloid-β (Aβ) peptides that promote the formation of pathogenic aggregates. APP mutations do not seem to impair the physiological functions of APP. In contrast, it has been proposed that PSEN mutations compromise γ-secretase-dependent and -independent functions of PSEN. However, PSEN mutations have mostly been studied in model systems that do not accurately refl ect the genetic background in FAD patients. In this review, we discuss the reported cellular phenotypes of APP and PSEN mutations, the current understanding of their molecular mechanisms, the need to generate faithful models of PSEN mutations, and the potential bias of APP and PSEN mutations on therapeutic strategies that target Aβ.
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Affiliation(s)
- Sascha Weggen
- Department of Neuropathology, Heinrich-Heine-University, Moorenstrasse 5, D-40225 Düsseldorf, Germany.
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23
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Saito T, Suemoto T, Brouwers N, Sleegers K, Funamoto S, Mihira N, Matsuba Y, Yamada K, Nilsson P, Takano J, Nishimura M, Iwata N, Van Broeckhoven C, Ihara Y, Saido TC. Potent amyloidogenicity and pathogenicity of Aβ43. Nat Neurosci 2011; 14:1023-32. [PMID: 21725313 DOI: 10.1038/nn.2858] [Citation(s) in RCA: 219] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 05/13/2011] [Indexed: 11/09/2022]
Abstract
The amyloid-β peptide Aβ42 is known to be a primary amyloidogenic and pathogenic agent in Alzheimer's disease. However, the role of Aβ43, which is found just as frequently in the brains of affected individuals, remains unresolved. We generated knock-in mice containing a pathogenic presenilin-1 R278I mutation that causes overproduction of Aβ43. Homozygosity was embryonic lethal, indicating that the mutation involves a loss of function. Crossing amyloid precursor protein transgenic mice with heterozygous mutant mice resulted in elevated Aβ43, impairment of short-term memory and acceleration of amyloid-β pathology, which accompanied pronounced accumulation of Aβ43 in plaque cores similar in biochemical composition to those observed in the brains of affected individuals. Consistently, Aβ43 showed a higher propensity to aggregate and was more neurotoxic than Aβ42. Other pathogenic presenilin mutations also caused overproduction of Aβ43 in a manner correlating with Aβ42 and with the age of disease onset. These findings indicate that Aβ43, an overlooked species, is potently amyloidogenic, neurotoxic and abundant in vivo.
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Affiliation(s)
- Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
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24
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Lichtenthaler SF, Haass C, Steiner H. Regulated intramembrane proteolysis--lessons from amyloid precursor protein processing. J Neurochem 2011; 117:779-96. [PMID: 21413990 DOI: 10.1111/j.1471-4159.2011.07248.x] [Citation(s) in RCA: 176] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Regulated intramembrane proteolysis (RIP) controls the communication between cells and the extracellular environment. RIP is essential in the nervous system, but also in other tissues. In the RIP process, a membrane protein typically undergoes two consecutive cleavages. The first one results in the shedding of its ectodomain. The second one occurs within its transmembrane domain, resulting in secretion of a small peptide and the release of the intracellular domain into the cytosol. The proteolytic cleavage fragments act as versatile signaling molecules or are further degraded. An increasing number of membrane proteins undergo RIP. These include growth factors, cytokines, cell adhesion proteins, receptors, viral proteins and signal peptides. A dysregulation of RIP is found in diseases, such as leukemia and Alzheimer's disease. One of the first RIP substrates discovered was the amyloid precursor protein (APP). RIP processing of APP controls the generation of the amyloid β-peptide, which is believed to cause Alzheimer's disease. Focusing on APP as the best-studied RIP substrate, this review describes the function and mechanism of the APP RIP proteases with the goal to elucidate cellular mechanisms and common principles of the RIP process in general.
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Affiliation(s)
- Stefan F Lichtenthaler
- DZNE-German Center for Neurodegenerative Diseases, Adolf-Butenandt-Institute, Biochemistry, Ludwig-Maximilians-University, Munich, Germany
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25
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Sahara N, Lewis J. Amyloid precursor protein and tau transgenic models of Alzheimer's disease: insights from the past and directions for the future. FUTURE NEUROLOGY 2010; 5:411-420. [PMID: 20730022 DOI: 10.2217/fnl.10.10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
During the last 20 years, our understanding of the mechanisms underlying Alzheimer's disease (AD) has considerably improved, in part owing to both in vitro and in vivo model systems. Studies in mice expressing both human amyloid precursor protein and human tau have provided clear evidence that amyloid-beta and tau interact in the pathogenesis of AD. Moreover, amyloid-beta toxicity has been shown to be tau-dependent since reducing tau levels prevents behavioral deficits and sudden death in amyloid precursor protein transgenic mice. As tau pathology preferentially develops in specific sites and spreads in a predictable manner across the brain, understanding the mechanism underlying tau dysfunction should be a focus in AD mouse modeling. A defined effort must be made to develop therapies that directly address the impact of tau dysfunction in the pathogenesis of AD. Finally, early diagnosis of AD is essential and this must be made possible by identification of early biomarkers, behavioral changes or use of novel imaging techniques.
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Affiliation(s)
- Naruhiko Sahara
- Department of Neuroscience, Mayo Clinic, Jacksonville FL 32224, USA
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26
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Winkler E, Hobson S, Fukumori A, Dümpelfeld B, Luebbers T, Baumann K, Haass C, Hopf C, Steiner H. Purification, pharmacological modulation, and biochemical characterization of interactors of endogenous human gamma-secretase. Biochemistry 2009; 48:1183-97. [PMID: 19159235 DOI: 10.1021/bi801204g] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Gamma-secretase is a unique intramembrane-cleaving protease complex, which cleaves the Alzheimer's disease-associated beta-amyloid precursor protein (APP) and a number of other type I membrane proteins. Human gamma-secretase consists of the catalytic subunit presenilin (PS) (PS1 or PS2), the substrate receptor nicastrin, APH-1 (APH-1a or APH-1b), and PEN-2. To facilitate in-depth biochemical analysis of gamma-secretase, we developed a fast and convenient multistep purification procedure for the endogenous enzyme. The enzyme was purified from HEK293 cells in an active form and had a molecular mass of approximately 500 kDa. Purified gamma-secretase was capable of producing the major amyloid-beta peptide (Abeta) species, such as Abeta40 and Abeta42, from a recombinant APP substrate in physiological ratios. Abeta generation could be modulated by pharmacological gamma-secretase modulators. Moreover, the Abeta42/Abeta40 ratio was strongly increased by purified PS1 L166P, an aggressive familial Alzheimer's disease mutant. Tandem mass spectrometry analysis revealed the consistent coisolation of several proteins with the known gamma-secretase core subunits. Among these were the previously described gamma-secretase interactors CD147 and TMP21 as well as other known interactors of these. Interestingly, the Niemann-Pick type C1 protein, a cholesterol transporter previously implicated in gamma-secretase-mediated processing of APP, was identified as a major copurifying protein. Affinity capture experiments using a biotinylated transition-state analogue inhibitor of gamma-secretase showed that these proteins are absent from active gamma-secretase complexes. Taken together, we provide an effective procedure for isolating endogenous gamma-secretase in considerably high grade, thus aiding further characterization of this pivotal enzyme. In addition, we provide evidence that the copurifying proteins identified are unlikely to be part of the active gamma-secretase enzyme.
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Affiliation(s)
- Edith Winkler
- Center for Integrated Protein Science Munich and Adolf-Butenandt-Institute, Department of Biochemistry, Laboratory for Neurodegenerative Disease Research, Ludwig-Maximilians-University, 80336 Munich, Germany
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27
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Welander H, Frånberg J, Graff C, Sundström E, Winblad B, Tjernberg LO. Abeta43 is more frequent than Abeta40 in amyloid plaque cores from Alzheimer disease brains. J Neurochem 2009; 110:697-706. [PMID: 19457079 DOI: 10.1111/j.1471-4159.2009.06170.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
One hallmark of Alzheimer disease (AD) is the extracellular deposition of the amyloid beta-peptide (Abeta) in senile plaques. Two major forms of Abeta are produced, 40 (Abeta40) and 42 (Abeta42) residues long. The most abundant form of Abeta is Abeta40, while Abeta42 is more hydrophobic and more prone to form toxic oligomers and the species of particular importance in early plaque formation. Thus, the length of the hydrophobic C-terminal seems to be very important for the oligomerization and neurotoxicity of the Abeta peptide. Here we investigated which Abeta species are deposited in AD brain. We analyzed plaque cores, prepared from occipital and frontal cortex, from sporadic and familial AD cases and performed a quantitative study using Abeta standard peptides. Cyanogen bromide was used to generate C-terminal Abeta fragments, which were analyzed by HPLC coupled to an electrospray ionisation ion trap mass spectrometer. We found a longer peptide, Abeta43, to be more frequent than Abeta40. No variants longer than Abeta43 could be observed in any of the brains. Immunohistochemistry was performed and was found to be in line with our findings. Abeta1-43 polymerizes rapidly and we suggest that this variant may be of importance for AD.
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Affiliation(s)
- Hedvig Welander
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Dainippon Sumitomo Pharma Alzheimer Center, Novum, Huddinge, Sweden.
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28
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Fluhrer R, Fukumori A, Martin L, Grammer G, Haug-Kröper M, Klier B, Winkler E, Kremmer E, Condron MM, Teplow DB, Steiner H, Haass C. Intramembrane proteolysis of GXGD-type aspartyl proteases is slowed by a familial Alzheimer disease-like mutation. J Biol Chem 2008; 283:30121-8. [PMID: 18768471 DOI: 10.1074/jbc.m806092200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
More than 150 familial Alzheimer disease (FAD)-associated missense mutations in presenilins (PS1 and PS2), the catalytic subunit of the gamma-secretase complex, cause aberrant amyloid beta-peptide (Abeta) production, by increasing the relative production of the highly amyloidogenic 42-amino acid variant. The molecular mechanism behind this pathological activity is unclear, and different possibilities ranging from a gain of function to a loss of function have been discussed. gamma-Secretase, signal peptide peptidase (SPP) and SPP-like proteases (SPPLs) belong to the same family of GXGD-type intramembrane cleaving aspartyl proteases and share several functional similarities. We have introduced the FAD-associated PS1 G384A mutation, which occurs within the highly conserved GXGD motif of PS1 right next to the catalytically critical aspartate residue, into the corresponding GXGD motif of the signal peptide peptidase-like 2b (SPPL2b). Compared with wild-type SPPL2b, mutant SPPL2b slowed intramembrane proteolysis of tumor necrosis factor alpha and caused a relative increase of longer intracellular cleavage products. Because the N termini of the secreted counterparts remain unchanged, the mutation selectively affects the liberation of the intracellular processing products. In vitro experiments demonstrate that the apparent accumulation of longer intracellular cleavage products is the result of slowed sequential intramembrane cleavage. The longer cleavage products are still converted to shorter peptides, however only after prolonged incubation time. This suggests that FAD-associated PS mutation may also result in reduced intramembrane cleavage of beta-amyloid precursor protein (betaAPP). Indeed, in vitro experiments demonstrate slowed intramembrane proteolysis by gamma-secretase containing PS1 with the G384A mutation. As compared with wild-type PS1, the mutation selectively slowed Abeta40 production, whereas Abeta42 generation remained unaffected. Thus, the PS1 G384A mutation causes a selective loss of function by slowing the processing pathway leading to the benign Abeta40.
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Affiliation(s)
- Regina Fluhrer
- Center for Integrated Protein Science Munich and Adolf-Butenandt-Institute, Department of Biochemistry, Laboratory for Neurodegenerative Disease Research, Ludwig-Maximilians-University, Munich 80336, Germany
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