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Iram F, Shahid M, Ansari J, Ashraf GM, Hassan MI, Islam A. Navigating the Maze of Alzheimer's disease by exploring BACE1: Discovery, current scenario, and future prospects. Ageing Res Rev 2024; 98:102342. [PMID: 38762102 DOI: 10.1016/j.arr.2024.102342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/04/2024] [Accepted: 05/13/2024] [Indexed: 05/20/2024]
Abstract
Alzheimer's disease (AD) is a chronic neurological condition that has become a leading cause of cognitive decline in elder individuals. Hardly any effective medication has been developed to halt the progression of AD due to the disease's complexity. Several theories have been put forward to clarify the mechanisms underlying AD etiology. The identification of amyloid plaques as a hallmark of AD has sparked the development of numerous drugs targeting the players involved in the amyloidogenic pathway, such as the β-site of amyloid precursor protein cleavage enzyme 1 (BACE1) blockers. Over the last ten years, preclinical and early experimental research has led several pharmaceutical companies to prioritize producing BACE1 inhibitors. Despite all these efforts, earlier discovered inhibitors were discontinued in consideration of another second-generation small molecules and recent BACE1 antagonists failed in the final stages of clinical trials because of the complications associated either with toxicity or effectiveness. In addition to discussing the difficulties associated with development of BACE1 inhibitors, this review aims to provide an overview of BACE1 and offer perspectives on the causes behind the failure of five recent BACE1 inhibitors, that would be beneficial for choosing effective treatment approaches in the future.
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Affiliation(s)
- Faiza Iram
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Mohammad Shahid
- Department of Basic Medical Sciences, College of Medicine, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Jaoud Ansari
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Ghulam Md Ashraf
- University of Sharjah, College of Health Sciences, and Research Institute for Medical and Health Sciences, Department of Medical Laboratory Sciences, Sharjah 27272, United Arab Emirates
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India.
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2
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Bhole RP, Chikhale RV, Rathi KM. Current biomarkers and treatment strategies in Alzheimer disease: An overview and future perspectives. IBRO Neurosci Rep 2024; 16:8-42. [PMID: 38169888 PMCID: PMC10758887 DOI: 10.1016/j.ibneur.2023.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 11/06/2023] [Accepted: 11/09/2023] [Indexed: 01/05/2024] Open
Abstract
Alzheimer's disease (AD), a progressive degenerative disorder first identified by Alois Alzheimer in 1907, poses a significant public health challenge. Despite its prevalence and impact, there is currently no definitive ante mortem diagnosis for AD pathogenesis. By 2050, the United States may face a staggering 13.8 million AD patients. This review provides a concise summary of current AD biomarkers, available treatments, and potential future therapeutic approaches. The review begins by outlining existing drug targets and mechanisms in AD, along with a discussion of current treatment options. We explore various approaches targeting Amyloid β (Aβ), Tau Protein aggregation, Tau Kinases, Glycogen Synthase kinase-3β, CDK-5 inhibitors, Heat Shock Proteins (HSP), oxidative stress, inflammation, metals, Apolipoprotein E (ApoE) modulators, and Notch signaling. Additionally, we examine the historical use of Estradiol (E2) as an AD therapy, as well as the outcomes of Randomized Controlled Trials (RCTs) that evaluated antioxidants (e.g., vitamin E) and omega-3 polyunsaturated fatty acids as alternative treatment options. Notably, positive effects of docosahexaenoic acid nutriment in older adults with cognitive impairment or AD are highlighted. Furthermore, this review offers insights into ongoing clinical trials and potential therapies, shedding light on the dynamic research landscape in AD treatment.
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Affiliation(s)
- Ritesh P. Bhole
- Department of Pharmaceutical Chemistry, Dr. D. Y. Patil institute of Pharmaceutical Sciences & Research, Pimpri, Pune, India
- Dr. D. Y. Patil Dental College and Hospital, Dr. D. Y. Patil Vidyapeeth, Pimpri, Pune 411018, India
| | | | - Karishma M. Rathi
- Department of Pharmacy Practice, Dr. D. Y. Patil institute of Pharmaceutical Sciences & Research, Pimpri, Pune, India
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3
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Vanova T, Sedmik J, Raska J, Amruz Cerna K, Taus P, Pospisilova V, Nezvedova M, Fedorova V, Kadakova S, Klimova H, Capandova M, Orviska P, Fojtik P, Bartova S, Plevova K, Spacil Z, Hribkova H, Bohaciakova D. Cerebral organoids derived from patients with Alzheimer's disease with PSEN1/2 mutations have defective tissue patterning and altered development. Cell Rep 2023; 42:113310. [PMID: 37864790 DOI: 10.1016/j.celrep.2023.113310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 08/09/2023] [Accepted: 10/04/2023] [Indexed: 10/23/2023] Open
Abstract
During the past two decades, induced pluripotent stem cells (iPSCs) have been widely used to study human neural development and disease. Especially in the field of Alzheimer's disease (AD), remarkable effort has been put into investigating molecular mechanisms behind this disease. Then, with the advent of 3D neuronal cultures and cerebral organoids (COs), several studies have demonstrated that this model can adequately mimic familial and sporadic AD. Therefore, we created an AD-CO model using iPSCs derived from patients with familial AD forms and explored early events and the progression of AD pathogenesis. Our study demonstrated that COs derived from three AD-iPSC lines with PSEN1(A246E) or PSEN2(N141I) mutations developed the AD-specific markers in vitro, yet they also uncover tissue patterning defects and altered development. These findings are complemented by single-cell sequencing data confirming this observation and uncovering that neurons in AD-COs likely differentiate prematurely.
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Affiliation(s)
- Tereza Vanova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center (ICRC), St. Anne's University Hospital, 60200 Brno, Czech Republic
| | - Jiri Sedmik
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Jan Raska
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center (ICRC), St. Anne's University Hospital, 60200 Brno, Czech Republic
| | - Katerina Amruz Cerna
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Petr Taus
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic
| | - Veronika Pospisilova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Marketa Nezvedova
- RECETOX, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic
| | - Veronika Fedorova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Sona Kadakova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Hana Klimova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Michaela Capandova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Petra Orviska
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Petr Fojtik
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center (ICRC), St. Anne's University Hospital, 60200 Brno, Czech Republic
| | - Simona Bartova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Karla Plevova
- Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic; Institute of Medical Genetics and Genomics, University Hospital Brno and Faculty of Medicine, Masaryk University, 61300 Brno, Czech Republic
| | - Zdenek Spacil
- RECETOX, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic
| | - Hana Hribkova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic
| | - Dasa Bohaciakova
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center (ICRC), St. Anne's University Hospital, 60200 Brno, Czech Republic.
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Abstract
Neurodegenerative diseases are characterized by the progressive loss of structure or function of neurons. In this Spotlight, we explore the idea that genetic forms of neurodegenerative disorders might be rooted in neural development. Focusing on Alzheimer's, Parkinson's and Huntington's disease, we first provide a brief overview of the pathology for these diseases. Although neurodegenerative diseases are generally thought of as late-onset diseases, we discuss recent evidence promoting the notion that they might be considered neurodevelopmental disorders. With this view in mind, we consider the suitability of animal models for studying these diseases, highlighting human-specific features of human brain development. We conclude by proposing that one such feature, human-specific regulation of neurogenic time, might be key to understanding the etiology and pathophysiology of human neurodegenerative disease.
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Affiliation(s)
- Khadijeh Shabani
- Institut du Cerveau – Paris Brain Institute – ICM, Sorbonne Université, Inserm, CNRS, Hôpital Pitié-Salpêtrière, 75013 Paris, France
| | - Bassem A. Hassan
- Institut du Cerveau – Paris Brain Institute – ICM, Sorbonne Université, Inserm, CNRS, Hôpital Pitié-Salpêtrière, 75013 Paris, France
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Cerebrospinal fluid tau levels are associated with abnormal neuronal plasticity markers in Alzheimer's disease. Mol Neurodegener 2022; 17:27. [PMID: 35346299 PMCID: PMC8962234 DOI: 10.1186/s13024-022-00521-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/13/2022] [Indexed: 12/15/2022] Open
Abstract
Background Increased total tau (t-tau) in cerebrospinal fluid (CSF) is a key characteristic of Alzheimer’s disease (AD) and is considered to result from neurodegeneration. T-tau levels, however, can be increased in very early disease stages, when neurodegeneration is limited, and can be normal in advanced disease stages. This suggests that t-tau levels may be driven by other mechanisms as well. Because tau pathophysiology is emerging as treatment target for AD, we aimed to clarify molecular processes associated with CSF t-tau levels. Methods We performed a proteomic, genomic, and imaging study in 1380 individuals with AD, in the preclinical, prodromal, and mild dementia stage, and 380 controls from the Alzheimer’s Disease Neuroimaging Initiative and EMIF-AD Multimodality Biomarker Discovery study. Results We found that, relative to controls, AD individuals with increased t-tau had increased CSF concentrations of over 400 proteins enriched for neuronal plasticity processes. In contrast, AD individuals with normal t-tau had decreased levels of these plasticity proteins and showed increased concentrations of proteins indicative of blood–brain barrier and blood-CSF barrier dysfunction, relative to controls. The distinct proteomic profiles were already present in the preclinical AD stage and persisted in prodromal and dementia stages implying that they reflect disease traits rather than disease states. Dysregulated plasticity proteins were associated with SUZ12 and REST signaling, suggesting aberrant gene repression. GWAS analyses contrasting AD individuals with and without increased t-tau highlighted several genes involved in the regulation of gene expression. Targeted analyses of SNP rs9877502 in GMNC, associated with t-tau levels previously, correlated in individuals with AD with CSF concentrations of 591 plasticity associated proteins. The number of APOE-e4 alleles, however, was not associated with the concentration of plasticity related proteins. Conclusions CSF t-tau levels in AD are associated with altered levels of proteins involved in neuronal plasticity and blood–brain and blood-CSF barrier dysfunction. Future trials may need to stratify on CSF t-tau status, as AD individuals with increased t-tau and normal t-tau are likely to respond differently to treatment, given their opposite CSF proteomic profiles. Supplementary Information The online version contains supplementary material available at 10.1186/s13024-022-00521-3.
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Cortical axon sub-population maintains density, but not turnover, of en passant boutons in the aged APP/PS1 amyloidosis model. Neurobiol Aging 2022; 115:29-38. [DOI: 10.1016/j.neurobiolaging.2022.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/10/2022] [Accepted: 03/12/2022] [Indexed: 11/21/2022]
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Bujdoso R, Smith A, Fleck O, Spiropoulos J, Andréoletti O, Thackray AM. Prion disease modelled in Drosophila. Cell Tissue Res 2022; 392:47-62. [PMID: 35092497 PMCID: PMC10113284 DOI: 10.1007/s00441-022-03586-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 01/17/2022] [Indexed: 11/02/2022]
Abstract
AbstractPrion diseases are fatal neurodegenerative conditions of humans and various vertebrate species that are transmissible between individuals of the same or different species. A novel infectious moiety referred to as a prion is considered responsible for transmission of these conditions. Prion replication is believed to be the cause of the neurotoxicity that arises during prion disease pathogenesis. The prion hypothesis predicts that the transmissible prion agent consists of PrPSc, which is comprised of aggregated misfolded conformers of the normal host protein PrPC. It is important to understand the biology of transmissible prions and to identify genetic modifiers of prion-induced neurotoxicity. This information will underpin the development of therapeutic and control strategies for human and animal prion diseases. The most reliable method to detect prion infectivity is by in vivo transmission in a suitable experimental host, which to date have been mammalian species. Current prion bioassays are slow, cumbersome and relatively insensitive to low titres of prion infectivity, and do not lend themselves to rapid genetic analysis of prion disease. Here, we provide an overview of our novel studies that have led to the establishment of Drosophila melanogaster, a genetically well-defined invertebrate host, as a sensitive, versatile and economically viable animal model for the detection of mammalian prion infectivity and genetic modifiers of prion-induced toxicity.
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Activation of Apoptosis in a βB1-CTGF Transgenic Mouse Model. Int J Mol Sci 2021; 22:ijms22041997. [PMID: 33671472 PMCID: PMC7922353 DOI: 10.3390/ijms22041997] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 02/09/2021] [Accepted: 02/12/2021] [Indexed: 11/23/2022] Open
Abstract
To reveal the pathomechanisms of glaucoma, a common cause of blindness, suitable animal models are needed. As previously shown, retinal ganglion cell and optic nerve degeneration occur in βB1-CTGF mice. Here, we aimed to determine possible apoptotic mechanisms and degeneration of different retinal cells. Hence, retinae were processed for immunohistology (n = 5–9/group) and quantitative real-time PCR analysis (n = 5–7/group) in 5- and 10-week-old βB1-CTGF and wildtype controls. We noted significantly more cleaved caspase 3+ cells in βB1-CTGF retinae at 5 (p = 0.005) and 10 weeks (p = 0.02), and a significant upregulation of Casp3 and Bax/Bcl2 mRNA levels (p < 0.05). Furthermore, more terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL+) cells were detected in transgenic mice at 5 (p = 0.03) and 10 weeks (p = 0.02). Neurofilament H staining (p = 0.01) as well as Nefh (p = 0.02) and Tubb3 (p = 0.009) mRNA levels were significantly decreased at 10 weeks. GABAergic synapse intensity was lower at 5 weeks, while no alterations were noted at 10 weeks. The glutamatergic synapse intensity was decreased at 5 (p = 0.007) and 10 weeks (p = 0.01). No changes were observed for bipolar cells, photoreceptors, and macroglia. We conclude that apoptotic processes and synapse loss precede neuronal death in this model. This slow progression rate makes the βB1-CTGF mice a suitable model to study primary open-angle glaucoma.
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9
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Transcriptional signature of prion-induced neurotoxicity in a Drosophila model of transmissible mammalian prion disease. Biochem J 2020; 477:833-852. [PMID: 32108870 PMCID: PMC7054746 DOI: 10.1042/bcj20190872] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/14/2020] [Accepted: 01/31/2020] [Indexed: 12/11/2022]
Abstract
Prion diseases are fatal transmissible neurodegenerative conditions of humans and animals that arise through neurotoxicity induced by PrP misfolding. The cellular and molecular mechanisms of prion-induced neurotoxicity remain undefined. Understanding these processes will underpin therapeutic and control strategies for human and animal prion diseases, respectively. Prion diseases are difficult to study in their natural hosts and require the use of tractable animal models. Here we used RNA-Seq-based transcriptome analysis of prion-exposed Drosophila to probe the mechanism of prion-induced neurotoxicity. Adult Drosophila transgenic for pan neuronal expression of ovine PrP targeted to the plasma membrane exhibit a neurotoxic phenotype evidenced by decreased locomotor activity after exposure to ovine prions at the larval stage. Pathway analysis and quantitative PCR of genes differentially expressed in prion-infected Drosophila revealed up-regulation of cell cycle activity and DNA damage response, followed by down-regulation of eIF2 and mTOR signalling. Mitochondrial dysfunction was identified as the principal toxicity pathway in prion-exposed PrP transgenic Drosophila. The transcriptomic changes we observed were specific to PrP targeted to the plasma membrane since these prion-induced gene expression changes were not evident in similarly treated Drosophila transgenic for cytosolic pan neuronal PrP expression, or in non-transgenic control flies. Collectively, our data indicate that aberrant cell cycle activity, repression of protein synthesis and altered mitochondrial function are key events involved in prion-induced neurotoxicity, and correlate with those identified in mammalian hosts undergoing prion disease. These studies highlight the use of PrP transgenic Drosophila as a genetically well-defined tractable host to study mammalian prion biology.
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Mao Y, Fisher DW, Yang S, Keszycki RM, Dong H. Protein-protein interactions underlying the behavioral and psychological symptoms of dementia (BPSD) and Alzheimer's disease. PLoS One 2020; 15:e0226021. [PMID: 31951614 PMCID: PMC6968845 DOI: 10.1371/journal.pone.0226021] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 11/19/2019] [Indexed: 12/25/2022] Open
Abstract
Alzheimer’s Disease (AD) is a devastating neurodegenerative disorder currently affecting 45 million people worldwide, ranking as the 6th highest cause of death. Throughout the development and progression of AD, over 90% of patients display behavioral and psychological symptoms of dementia (BPSD), with some of these symptoms occurring before memory deficits and therefore serving as potential early predictors of AD-related cognitive decline. However, the biochemical links between AD and BPSD are not known. In this study, we explored the molecular interactions between AD and BPSD using protein-protein interaction (PPI) networks built from OMIM (Online Mendelian Inheritance in Man) genes that were related to AD and two distinct BPSD domains, the Affective Domain and the Hyperactivity, Impulsivity, Disinhibition, and Aggression (HIDA) Domain. Our results yielded 8 unique proteins for the Affective Domain (RHOA, GRB2, PIK3R1, HSPA4, HSP90AA1, GSK3beta, PRKCZ, and FYN), 5 unique proteins for the HIDA Domain (LRP1, EGFR, YWHAB, SUMO1, and EGR1), and 6 shared proteins between both BPSD domains (APP, UBC, ELAV1, YWHAZ, YWHAE, and SRC) and AD. These proteins might suggest specific targets and pathways that are involved in the pathogenesis of these BPSD domains in AD.
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Affiliation(s)
- Yimin Mao
- School of Information and Technology, Jiangxi University of Science and Technology, Jiangxi, China
- Applied Science Institute, Jiangxi University of Science and Technology, Jiangxi, China
| | - Daniel W. Fisher
- Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Shuxing Yang
- School of Information and Technology, Jiangxi University of Science and Technology, Jiangxi, China
| | - Rachel M. Keszycki
- Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Hongxin Dong
- Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
- * E-mail:
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Ju DT, K AK, Kuo WW, Ho TJ, Chang RL, Lin WT, Day CH, Viswanadha VVP, Liao PH, Huang CY. Bioactive Peptide VHVV Upregulates the Long-Term Memory-Related Biomarkers in Adult Spontaneously Hypertensive Rats. Int J Mol Sci 2019; 20:E3069. [PMID: 31234585 PMCID: PMC6627188 DOI: 10.3390/ijms20123069] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/20/2019] [Accepted: 06/21/2019] [Indexed: 12/19/2022] Open
Abstract
Hypertension is one of the growing risk factors for the progression of long-term memory loss. Hypertension-mediated memory loss and treatment remain not thoroughly elucidated to date. Plant-based natural compounds are an alternative solution to treating human diseases without side effects associated with commercial drugs. This study reveals that bioactive peptides extracted from soy hydrolysates mimic hypertension-mediated memory loss and neuronal degeneration and alters the memory molecular pathway in spontaneously hypertensive rats (SHR). The SHR animal model was treated with bioactive peptide VHVV (10 mg/kg/oral administration) and angiotensin-converting-enzyme (ACE) inhibitors (5 mg/kg/oral administration) for 24 weeks. We evaluated molecular level expression of brain-derived neurotrophic factor (BDNF), cAMP response element binding protein (CREB), and survival markers phospho-protein kinase B (P-AKT) and phosphoinositide 3-kinase (PI3K) after 24 weeks of treatment for SHR in this study. Western blotting, hematoxylin and eosin (H&E) staining, and immunohistochemistry showed long-term memory loss and neuronal degeneration in SHR animals. Bioactive peptide VHVV-treated animals upregulated the expression of long-term memory-relate proteins and neuronal survival. Spontaneously hypertensive rats treated with oral administration of bioactive peptide VHVV had activated CREB-mediated downstream proteins which may reduce hypertension-mediated long-term memory loss and maintain neuronal survival.
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Affiliation(s)
- Da-Tong Ju
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan.
| | - Ashok Kumar K
- Graduate Institute of Basic Medical Science, China Medical University, Taichung 404, Taiwan.
| | - Wei-Wen Kuo
- Department of Biological Science and Technology, China Medical University, Taichung 404, Taiwan.
| | - Tsung-Jung Ho
- Department of Chinese Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Tzu Chi University, Hualien 970, Taiwan.
| | - Ruey-Lin Chang
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan.
| | - Wan-Teng Lin
- Department of Hospitality Management, College of Agriculture, Tunghai University, Taichung 407, Taiwan.
| | | | | | - Po-Hsiang Liao
- Graduate Institute of Basic Medical Science, China Medical University, Taichung 404, Taiwan.
- Holistic Education Center, Tzu Chi University of Science and Technology, Hualien 970, Taiwan.
- Cardiovascular research center, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 970, Taiwan.
| | - Chih-Yang Huang
- Holistic Education Center, Tzu Chi University of Science and Technology, Hualien 970, Taiwan.
- Cardiovascular research center, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 970, Taiwan.
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 404, Taiwan.
- Department of Biotechnology, Asia University, Taichung 413, Taiwan.
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Riazimontazer E, Sadeghpour H, Nadri H, Sakhteman A, Tüylü Küçükkılınç T, Miri R, Edraki N. Design, synthesis and biological activity of novel tacrine-isatin Schiff base hybrid derivatives. Bioorg Chem 2019; 89:103006. [PMID: 31158577 DOI: 10.1016/j.bioorg.2019.103006] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 03/10/2019] [Accepted: 05/19/2019] [Indexed: 12/13/2022]
Abstract
A series of novel tacrine-isatin Schiff base hybrid derivatives (7a-p) were designed, synthesized and evaluated as multi-target candidates against Alzheimer's disease (AD). The biological assays indicated that most of these compounds displayed potent inhibitory activity toward acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) and specific selectivity for AChE over BuChE. It was also found that they act as excellent metal chelators. The compounds 7k and 7m were found to be good inhibitors of AChE-induced amyloid-beta (Aβ) aggregation. Most of the compounds inhibited AChE with the IC50 values, ranging from 0.42 nM to 79.66 nM. Amongst them, 7k, 7m and 7p, all with a 6 carbon linker between tacrine and isatin Schiff base exhibited the strongest inhibitory activity against AChE with IC50 values of 0.42 nM, 0.62 nM and 0.95 nM, respectively. They were 92-, 62- and 41-fold more active than tacrine (IC50 = 38.72 nM) toward AChE. Most of the compounds also showed a potent BuChE inhibition among which 7d with an IC50 value of 0.11 nM for BuChE is the most potent one (56-fold more potent than that of tacrine (IC50 = 6.21 nM)). In addition, most compounds exhibited the highest metal chelating property. Kinetic and molecular modeling studies revealed that 7k is a mixed-type inhibitor, capable of binding to catalytic and peripheral site of AChE. Our findings make this hybrid scaffold an excellent candidate to modify current drugs in treating Alzheimer's disease (AD).
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Affiliation(s)
- E Riazimontazer
- Department of Medicinal Chemistry, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran
| | - H Sadeghpour
- Department of Medicinal Chemistry, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - H Nadri
- Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - A Sakhteman
- Department of Medicinal Chemistry, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - T Tüylü Küçükkılınç
- Hacettepe University, Faculty of Pharmacy, Department of Biochemistry, Sihhiye-Ankara, Turkey
| | - R Miri
- Department of Medicinal Chemistry, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran; Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Edraki
- Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
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Ashford JW, Tarpin-Bernard F, Ashford CB, Ashford MT. A Computerized Continuous-Recognition Task for Measurement of Episodic Memory. J Alzheimers Dis 2019; 69:385-399. [PMID: 30958384 PMCID: PMC6597981 DOI: 10.3233/jad-190167] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Based on clinical observations of severe episodic memory (EM) impairment in dementia of Alzheimer’s disease (AD), a brief, computerized EM test was developed for AD patient evaluation. A continuous recognition task (CRT) was chosen because of its extensive use in EM research. Initial experience with this computerized CRT (CCRT) showed patients were very engaged in the test, but AD patients had marked failure in recognizing repeated images. Subsequently, the test was administered to audiences, and then a two-minute online version was implemented (http://www.memtrax.com). The online CCRT shows 50 images, 25 unique and 25 repeats, which subjects respectively either try to remember or indicate recognition as quickly as possible. The pictures contain 5 sets of 5 images of scenes or objects (e.g., mountains, clothing, vehicles, etc.). A French company (HAPPYneuron, SAS) provided the test for 2 years, with these results. Of 18,477 individuals, who indicated sex and age 21–99 years and took the test for the first time, 18,007 individuals performed better than chance. In this group, age explained 1.5% of the variance in incorrect responses and 3.5% of recognition time variance, indicating considerable population variability. However, when averaging for specific year of age, age explained 58% of percent incorrect variance and 78% of recognition time variance, showing substantial population variability but a major age effect. There were no apparent sex effects. Further studies are indicated to determine the value of this CCRT as an AD screening test and validity as a measure of EM impairment in other clinical conditions.
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Affiliation(s)
- J Wesson Ashford
- Department of Psychiatry & Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, USA.,War Related Illness & Injury Study Center, VA Palo Alto Health Care System, Palo Alto, CA, USA
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Sánchez-Ramón S, Faure F. The Thymus/Neocortex Hypothesis of the Brain: A Cell Basis for Recognition and Instruction of Self. Front Cell Neurosci 2017; 11:340. [PMID: 29163052 PMCID: PMC5663735 DOI: 10.3389/fncel.2017.00340] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Accepted: 10/13/2017] [Indexed: 12/18/2022] Open
Abstract
The recognition of internal and external sources of stimuli, the self from non-self, seems to be an intrinsic property to the adequate functioning of the immune system and the nervous system, both complex network systems that have evolved to safeguard the self biological identity of the organism. The mammalian brain development relies on dynamic and adaptive processes that are now well described. However, the rules dictating this highly constrained developmental process remain elusive. Here we hypothesize that there is a cellular basis for brain selfhood, based on the analogy of the global mechanisms that drive the self/non-self recognition and instruction by the immune system. In utero education within the thymus by multi-step selection processes discard overly low and high affinity T-lymphocytes to self stimuli, thus avoiding expendable or autoreactive responses that might lead to harmful autoimmunity. We argue that the self principle is one of the chief determinants of neocortical brain neurogenesis. According to our hypothesis, early-life education on self at the subcortical plate of the neocortex by selection processes might participate in the striking specificity of neuronal repertoire and assure efficiency and self tolerance. Potential implications of this hypothesis in self-reactive neurological pathologies are discussed, particularly involving consciousness-associated pathophysiological conditions, i.e., epilepsy and schizophrenia, for which we coined the term autophrenity.
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Affiliation(s)
- Silvia Sánchez-Ramón
- Department of Clinical Immunology and IdISSC, Hospital Clínico San Carlos, Madrid, Spain.,Department of Microbiology I, School of Medicine, Complutense University of Madrid, Madrid, Spain
| | - Florence Faure
- PSL Research University, INSERM U932, Institut Curie, Paris, France
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15
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Do Carmo S, Crynen G, Paradis T, Reed J, Iulita MF, Ducatenzeiler A, Crawford F, Cuello AC. Hippocampal Proteomic Analysis Reveals Distinct Pathway Deregulation Profiles at Early and Late Stages in a Rat Model of Alzheimer's-Like Amyloid Pathology. Mol Neurobiol 2017; 55:3451-3476. [PMID: 28502044 DOI: 10.1007/s12035-017-0580-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 04/26/2017] [Indexed: 01/01/2023]
Abstract
The cerebral accumulation and cytotoxicity of amyloid beta (Aβ) is central to Alzheimer's pathogenesis. However, little is known about how the amyloid pathology affects the global expression of brain proteins at different disease stages. In order to identify genotype and time-dependent significant changes in protein expression, we employed quantitative proteomics analysis of hippocampal tissue from the McGill-R-Thy1-APP rat model of Alzheimer-like amyloid pathology. McGill transgenic rats were compared to wild-type rats at early and late pathology stages, i.e., when intraneuronal Aβ amyloid burden is conspicuous and when extracellular amyloid plaques are abundant with more pronounced cognitive deficits. After correction for multiple testing, the expression levels of 64 proteins were found to be considerably different in transgenic versus wild-type rats at the pre-plaque stage (3 months), and 86 proteins in the post-plaque group (12 months), with only 9 differentially regulated proteins common to the 2 time-points. This minimal overlap supports the hypothesis that different molecular pathways are affected in the hippocampus at early and late stages of the amyloid pathology throughout its continuum. At early stages, disturbances in pathways related to cellular responses to stress, protein homeostasis, and neuronal structure are predominant, while disturbances in metabolic energy generation dominate at later stages. These results shed new light on the molecular pathways affected by the early accumulation of Aβ and how the evolving amyloid pathology impacts other complex metabolic pathways.
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Affiliation(s)
- Sonia Do Carmo
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | | | - Tiffany Paradis
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Jon Reed
- Roskamp Institute, Sarasota, FL, USA
| | - M Florencia Iulita
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Adriana Ducatenzeiler
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | | | - A Claudio Cuello
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada. .,Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada. .,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.
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16
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Blazquez-Llorca L, Valero-Freitag S, Rodrigues EF, Merchán-Pérez Á, Rodríguez JR, Dorostkar MM, DeFelipe J, Herms J. High plasticity of axonal pathology in Alzheimer's disease mouse models. Acta Neuropathol Commun 2017; 5:14. [PMID: 28173876 PMCID: PMC5296955 DOI: 10.1186/s40478-017-0415-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/26/2017] [Indexed: 02/05/2023] Open
Abstract
Axonal dystrophies (AxDs) are swollen and tortuous neuronal processes that are associated with extracellular depositions of amyloid β (Aβ) and have been observed to contribute to synaptic alterations occurring in Alzheimer's disease. Understanding the temporal course of this axonal pathology is of high relevance to comprehend the progression of the disease over time. We performed a long-term in vivo study (up to 210 days of two-photon imaging) with two transgenic mouse models (dE9xGFP-M and APP-PS1xGFP-M). Interestingly, AxDs were formed only in a quarter of GFP-expressing axons near Aβ-plaques, which indicates a selective vulnerability. AxDs, especially those reaching larger sizes, had long lifetimes and appeared as highly plastic structures with large variations in size and shape and axonal sprouting over time. In the case of the APP-PS1 mouse only, the formation of new long axonal segments in dystrophic axons (re-growth phenomenon) was observed. Moreover, new AxDs could appear at the same point of the axon where a previous AxD had been located before disappearance (re-formation phenomenon). In addition, we observed that most AxDs were formed and developed during the imaging period, and numerous AxDs had already disappeared by the end of this time. This work is the first in vivo study analyzing quantitatively the high plasticity of the axonal pathology around Aβ plaques. We hypothesized that a therapeutically early prevention of Aβ plaque formation or their growth might halt disease progression and promote functional axon regeneration and the recovery of neural circuits.
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17
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Tarazi H, Odeh RA, Al-Qawasmeh R, Yousef IA, Voelter W, Al-Tel TH. Design, synthesis and SAR analysis of potent BACE1 inhibitors: Possible lead drug candidates for Alzheimer's disease. Eur J Med Chem 2017; 125:1213-1224. [DOI: 10.1016/j.ejmech.2016.11.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 10/12/2016] [Accepted: 11/10/2016] [Indexed: 11/29/2022]
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Schaefers ATU, Teuchert-Noodt G. Developmental neuroplasticity and the origin of neurodegenerative diseases. World J Biol Psychiatry 2016; 17:587-599. [PMID: 23705632 DOI: 10.3109/15622975.2013.797104] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES Neurodegenerative diseases like Alzheimer's and Parkinson's Disease, marked by characteristic protein aggregations, are more and more accepted to be synaptic disorders and to arise from a combination of genetic and environmental factors. In this review we propose our concept that neuroplasticity might constitute a link between early life challenges and neurodegeneration. METHODS After introducing the general principles of neuroplasticity, we show how adverse environmental stimuli during development impact adult neuroplasticity and might lead to neurodegenerative processes. RESULTS There are significant overlaps between neurodevelopmental and neurodegenerative processes. Proteins that represent hallmarks of neurodegeneration are involved in plastic processes under physiological conditions. Brain regions - particularly the hippocampus - that retain life-long plastic capacities are the key targets of neurodegeneration. Neuroplasticity is highest in young age making the brain more susceptible to external influences than later in life. Impacts during critical periods have life-long consequences on neuroplasticity and structural self-organization and are known to be common risk factors for neurodegenerative diseases. CONCLUSIONS Several lines of evidence support a link between developmental neuroplasticity and neurodegenerative processes later in life. A deeper insight into these processes is necessary to design strategies to mitigate or even prevent neurodegenerative pathologies.
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Arendt T, Stieler JT, Holzer M. Tau and tauopathies. Brain Res Bull 2016; 126:238-292. [DOI: 10.1016/j.brainresbull.2016.08.018] [Citation(s) in RCA: 333] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 12/11/2022]
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20
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Lista S, Hampel H. Synaptic degeneration and neurogranin in the pathophysiology of Alzheimer’s disease. Expert Rev Neurother 2016; 17:47-57. [DOI: 10.1080/14737175.2016.1204234] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Simone Lista
- AXA Research Fund & UPMC Chair, Paris, France
- IHU-A-ICM – Paris Institute of Translational Neurosciences, Pitié-Salpêtrière University Hospital, Paris, France
| | - Harald Hampel
- AXA Research Fund & UPMC Chair, Paris, France
- Department of Neurology, Sorbonne Universities, Institute of Memory and Alzheimer’s Disease (IM2A) & Brain and Spine Institute (ICM) UMR S 1127, Pitié-Salpêtrière University Hospital, Pierre and Marie Curie University, Paris 06, Paris, France
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Abstract
A prevailing view in neuroscience is that the mature CNS has relatively little capacity to respond adaptively to injury. Recent data indicating a high degree of structural plasticity in the adult brain provides an impetus to reexamine how central neurons react to trauma. An analysis of both in vivo and in vitro experimental studies demonstrates that certain brain neurons may have an intrinsic ability to respond to structural injury by an attempt at regenerative sprouting. Indeed, aberrant sprouting following neuronal injury may be the cause of epilepsy following brain trauma and may underlie the neuronal changes stimulated by plaque formation in Alzheimer’s disease. An understanding of the stereotypical reaction to injury of different CNS neurons, as well as the role of nonneuronal cells, may provide new avenues for therapeutic intervention for a range of neurodegenerative diseases and “acquired” forms of CNS injury.
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22
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Reverte I, Peris-Sampedro F, Basaure P, Campa L, Suñol C, Moreno M, Domingo JL, Colomina MT. Attentional performance, impulsivity, and related neurotransmitter systems in apoE2, apoE3, and apoE4 female transgenic mice. Psychopharmacology (Berl) 2016; 233:295-308. [PMID: 26497539 DOI: 10.1007/s00213-015-4113-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 10/06/2015] [Indexed: 12/27/2022]
Abstract
RATIONALE The apolipoprotein E (apoE) genotype influences cognitive performance in humans depending on age and sex. While the detrimental role of the apoE4 isoform on spatial learning and memory has been well-established in humans and rodents, less is known on its impact on the executive functions. OBJECTIVES We aimed to evaluate the effect of apoE isoforms (apoE2, apoE3, apoE4) on visuospatial attention and inhibitory control performance in female transgenic mice, and to determine the neurochemical and neuropharmacological basis of this potential relationship. METHODS Female mice carrying apoE2, apoE3, and apoE4 were trained in the five-choice serial reaction time task (5-CSRTT). Upon a stable performance, we manipulated the inter-trial interval and the stimulus duration to elicit impulsive responding and engage attention respectively. We further performed a pharmacological challenge by administering cholinergic and GABAergic agents. Finally, we analyzed the levels of brain amino acids and monoamines by using reversed phase high-performance liquid chromatography (HPLC). RESULTS ApoE4 mice showed a deficient inhibitory control as revealed by increased perseveration and premature responding. When attention was challenged, apoE4 mice also showed a higher drop in accuracy. The adverse effect of scopolamine on the task was attenuated in apoE4 mice compared to apoE2 and apoE3. Furthermore, apoE4 mice showed less dopamine in the frontal cortex than apoE2 mice. CONCLUSIONS We confirmed that the apoE genotype influences attention and inhibitory control in female transgenic mice. The influence of apoE isoforms in the brain neuromodulatory system may explain the cognitive and behavioral differences attributable to the genotype.
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23
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Arendt T, Brückner MK, Lösche A. Regional mosaic genomic heterogeneity in the elderly and in Alzheimer's disease as a correlate of neuronal vulnerability. Acta Neuropathol 2015; 130:501-10. [PMID: 26298468 DOI: 10.1007/s00401-015-1465-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/31/2015] [Accepted: 07/31/2015] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by fibrillary aggregates of Aβ peptide and tau protein. The distribution of these pathological hallmarks throughout the brain is not random; it follows a predictive pattern that is used for pathological staging. However, most etiopathogenetic concepts, irrespective of whether they focus on Aβ or tau pathology, leave a key question unanswered: what is the explanation for the different vulnerabilities of brain regions in AD? The pattern of regional progression of neurofibrillary degeneration in AD to some extent inversely recapitulates ontogenetic and phylogenetic brain development. Accordingly, degeneration preferentially affects brain areas that have recently been acquired or restructured during anthropoid evolution, which means that the involvement of a neurodevelopmental mechanism is highly likely. Since evolutionary expansion of the neocortex is based on a substantial extension of the mitotic activity of progenitor cells, we propose a conceptual link between neurogenesis in anthropoid primates and a higher risk of accumulating mitotic errors that give rise to genomic aberrations commonly referred to as DNA content variation (DCV). If increased rates of DCV make neurons more vulnerable to AD-related pathology, one might expect there to be a higher rate of DCV in areas that are affected very early during the course of AD, as compared to areas which are hardly affected or are affected only during the most advanced stages. Therefore, in the present study, we comparatively analyzed the DCV in five different cortical areas that are affected during the early stage (entorhinal cortex), the intermediate stage (temporal, frontal, and parietal association cortex), and the late stage (primary sensory occipital cortex) of AD in both normal elderly subjects and AD patients. On average, we observed about 10 % neuronal mosaic DCV in the normal elderly and a two- to threefold increase in DCV in AD patients. We were able to demonstrate, moreover, that the neuronal DCV in the cerebral cortex of the normal elderly as well as the increased neuronal DCV in AD patients are not randomly distributed but instead show systematic regional differences which correspond to differences in vulnerability. These findings provide additional evidence that mosaic genomic heterogeneity may play a key role in AD pathology.
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Affiliation(s)
- Thomas Arendt
- Department of Molecular and Cellular Mechanism of Neurodegeneration, Paul Flechsig Institute for Brain Research, Universität Leipzig, Liebigstrasse 19, 04103, Leipzig, Germany.
| | - Martina K Brückner
- Department of Molecular and Cellular Mechanism of Neurodegeneration, Paul Flechsig Institute for Brain Research, Universität Leipzig, Liebigstrasse 19, 04103, Leipzig, Germany
| | - Andreas Lösche
- Core Unit Fluorescence Technologies of the Medical Faculty, Universität Leipzig, Liebigstrasse 19, 04103, Leipzig, Germany
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Bujdoso R, Landgraf M, Jackson WS, Thackray AM. Prion-induced neurotoxicity: Possible role for cell cycle activity and DNA damage response. World J Virol 2015; 4:188-197. [PMID: 26279981 PMCID: PMC4534811 DOI: 10.5501/wjv.v4.i3.188] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 03/19/2015] [Accepted: 04/30/2015] [Indexed: 02/05/2023] Open
Abstract
Protein misfolding neurodegenerative diseases arise through neurotoxicity induced by aggregation of host proteins. These conditions include Alzheimer’s disease, Huntington’s disease, Parkinson’s disease, motor neuron disease, tauopathies and prion diseases. Collectively, these conditions are a challenge to society because of the increasing aged population and through the real threat to human food security by animal prion diseases. It is therefore important to understand the cellular and molecular mechanisms that underlie protein misfolding-induced neurotoxicity as this will form the basis for designing strategies to alleviate their burden. Prion diseases are an important paradigm for neurodegenerative conditions in general since several of these maladies have now been shown to display prion-like phenomena. Increasingly, cell cycle activity and the DNA damage response are recognised as cellular events that participate in the neurotoxic process of various neurodegenerative diseases, and their associated animal models, which suggests they are truly involved in the pathogenic process and are not merely epiphenomena. Here we review the role of cell cycle activity and the DNA damage response in neurodegeneration associated with protein misfolding diseases, and suggest that these events contribute towards prion-induced neurotoxicity. In doing so, we highlight PrP transgenic Drosophila as a tractable model for the genetic analysis of transmissible mammalian prion disease.
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25
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Li JM, Liu C, Hu X, Cai Y, Ma C, Luo XG, Yan XX. Inverse correlation between Alzheimer's disease and cancer: implication for a strong impact of regenerative propensity on neurodegeneration? BMC Neurol 2014; 14:211. [PMID: 25394409 PMCID: PMC4232711 DOI: 10.1186/s12883-014-0211-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/24/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Recent studies have revealed an inverse epidemiological correlation between Alzheimer's disease (AD) and cancer - patients with AD show a reduced risk of cancer, while cancer survivors are less likely to develop AD. These late discoveries in human subjects call for explorative studies to unlock the underlying biological mechanism, but also may shed new light on conceptual interrogation of the principal pathogenic players in AD etiology. DISCUSSION Here we hypothesize that this negative correlation reflects a rebalance of biosynthetic propensity between body systems under the two disease statuses. In normal condition the body cellular systems are maintained homeostatically under a balanced cell degenerative vs. surviving/regenerative propensities, determined by biosynthetic resources for anabolic processing. AD pathogenesis involves neurodegeneration but also aberrant regenerative, or reactive anabolic, burden, while cancer development is driving by uncontrolled proliferation inherent with excessive anabolic activity. The aberrant neural regenerative propensity in AD pathogenesis and the uncontrolled cellular proliferative propensity in cancer pathogeneses can manifest as competitive processes, which could result in the inverse epidemiological correlation seen among the elderly. SUMMARY The reduced prevalence of AD in cancer survivors may implicate a strong impact of aberrant neural regenerative burden in neurodegeneration. Further explorative studies into the inverse correlation between AD and cancer should include examinations of the proliferative propensity of tumor cells in AD models, and the development of AD-like neuropathology in cancer models as well as following anti-proliferative drug treatment.
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Affiliation(s)
- Jian-Ming Li
- />Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, 410013 Hunan China
- />Neuroscience Research Center, Changsha Medical University, Changsha, 410219 Hunan China
| | - Chao Liu
- />Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, 410013 Hunan China
- />Department of Neurology, The First Hospital of Changsha, Changsha, 410005 Hunan China
| | - Xia Hu
- />Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, 410013 Hunan China
| | - Yan Cai
- />Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, 410013 Hunan China
| | - Chao Ma
- />Department of Human Anatomy, Histology & Embryology, Institute of Basic Medical Sciences, Neuroscience Center, Chinese Academy of Medical Sciences; School of Basic Medicine, Peking Union Medical College, Beijing, 100730 China
| | - Xue-Gang Luo
- />Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, 410013 Hunan China
| | - Xiao-Xin Yan
- />Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, 410013 Hunan China
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26
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Vinitha E, Singh HJ, Kakalij RM, Kshirsagar RP, Kumar BH, Diwan PV. Neuroprotective effect of Prunus avium on streptozotocin induced neurotoxicity in mice. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.bionut.2014.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Yan XX, Ma C, Gai WP, Cai H, Luo XG. Can BACE1 inhibition mitigate early axonal pathology in neurological diseases? J Alzheimers Dis 2014; 38:705-18. [PMID: 24081378 DOI: 10.3233/jad-131400] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
β-Secretase-1 (BACE1) is the rate-limiting enzyme for the genesis of amyloid-β (Aβ) peptides, the main constituents of the amyloid plaques in the brains of Alzheimer's disease (AD) patients. BACE1 is being evaluated as an anti-Aβ target for AD therapy. Recent studies indicate that BACE1 elevation is associated with axonal and presynaptic pathology during plaque development. Evidence also points to a biological role for BACE1 in axonal outgrowth and synapse formation during development. Axonal, including presynaptic, pathology exists in AD as well as many other neurological disorders such as Parkinson's disease, epilepsy, stroke, and trauma. In this review, we discuss pharmaceutical BACE1 inhibition as a therapeutic option for axonal pathogenesis, in addition to amyloid pathology. We first introduce the amyloidogenic processing of amyloid-β protein precursor and describe the normal expression pattern of the amyloidogenic proteins in the brain, with an emphasis on BACE1. We then address BACE1 elevation relative to amyloid plaque development, followed by updating recent understanding of a neurotrophic role of BACE1 in axon and synapse development. We further elaborate the occurrence of axonal pathology in some other neurological conditions. Finally, we propose pharmacological inhibition of excessive BACE1 activity as an option to mitigate early axonal pathology occurring in AD and other neurological disorders.
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Affiliation(s)
- Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, Hunan, China
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28
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Cochran JN, Hall AM, Roberson ED. The dendritic hypothesis for Alzheimer's disease pathophysiology. Brain Res Bull 2014; 103:18-28. [PMID: 24333192 PMCID: PMC3989444 DOI: 10.1016/j.brainresbull.2013.12.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 11/28/2013] [Accepted: 12/02/2013] [Indexed: 01/02/2023]
Abstract
Converging evidence indicates that processes occurring in and around neuronal dendrites are central to the pathogenesis of Alzheimer's disease. These data support the concept of a "dendritic hypothesis" of AD, closely related to the existing synaptic hypothesis. Here we detail dendritic neuropathology in the disease and examine how Aβ, tau, and AD genetic risk factors affect dendritic structure and function. Finally, we consider potential mechanisms by which these key drivers could affect dendritic integrity and disease progression. These dendritic mechanisms serve as a framework for therapeutic target identification and for efforts to develop disease-modifying therapeutics for Alzheimer's disease.
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Affiliation(s)
- J Nicholas Cochran
- Center for Neurodegeneration and Experimental Therapeutics, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Alicia M Hall
- Center for Neurodegeneration and Experimental Therapeutics, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Erik D Roberson
- Center for Neurodegeneration and Experimental Therapeutics, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, United States.
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29
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van Groen T, Miettinen P, Kadish I. Axonal tract tracing for delineating interacting brain regions: implications for Alzheimer's disease-associated memory. FUTURE NEUROLOGY 2014; 9:89-98. [PMID: 24678267 DOI: 10.2217/fnl.13.67] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We are studying the projections from the entorhinal cortex to the hippocampal formation in the mouse. The dentate gyrus is innervated by the lateral entorhinal cortex (lateral perforant path) and medial entorhinal cortex (medial perforant path). The entorhinal cortex also projects to hippocampal areas CA3 and CA1, and to the subiculum. In young transgenic Alzheimer's disease mouse models (before amyloid-β pathology), the connections are not different from normal mice. In Alzheimer's disease mice with pathology, two changes occur: first, dystrophic axon endings appear near amyloid-β plaques, and second, there are sparse aberrant axon terminations not in the appropriate area or lamina of the hippocampus. Furthermore, MRI-diffusion tensor imaging analysis indicates a decrease in the quality of the white matter tracts connecting the hippocampus to the brain; in other words, the fimbria/fornix and perforant path. Similar changes in white matter integrity have been found in Alzheimer's disease patients and could potentially be used as early indicators of disease onset.
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Affiliation(s)
- Thomas van Groen
- Department of Cell, Developmental & Integrative Biology, University of Alabama at Birmingham, 1900 University Boulevard, THT 912, Birmingam, AL 35294-0006, USA
| | - Pasi Miettinen
- Department of Neuroscience, University of Eastern Finland, FIN 70211, Kuopio, Finland
| | - Inga Kadish
- Department of Cell, Developmental & Integrative Biology, University of Alabama at Birmingham, 1900 University Boulevard, THT 912, Birmingam, AL 35294-0006, USA
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30
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Kato-Negishi M, Morimoto Y, Onoe H, Takeuchi S. Millimeter-sized neural building blocks for 3D heterogeneous neural network assembly. Adv Healthc Mater 2013; 2:1564-70. [PMID: 23828857 DOI: 10.1002/adhm.201300052] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 03/27/2013] [Indexed: 01/05/2023]
Abstract
A millimeter-sized neural building block (NBB) shows high versatility to form a 3D heterogeneous neural component. A millimeter-sized 3D neural network between heterogeneous neural tissues is established, and an efficient technique is then developed to observe the spatiotemporal metrological changes of single neuron in the NBB. This technique allows the visualization of axonal extension, dendritic branching, and morphological changes of presynaptic components and synapses in real time.
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Affiliation(s)
- Midori Kato-Negishi
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan; Takeuchi Biohybrid Innovation Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Agency (JST), 4-6-1, Komaba, Meguro-ku, Tokyo 153-8505, Japan
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Cheng X, Wu J, Geng M, Xiong J. Role of synaptic activity in the regulation of amyloid beta levels in Alzheimer's disease. Neurobiol Aging 2013; 35:1217-32. [PMID: 24368087 DOI: 10.1016/j.neurobiolaging.2013.11.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Revised: 11/03/2013] [Accepted: 11/24/2013] [Indexed: 01/27/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Accumulation of amyloid-beta (Aβ) peptides is regarded as the critical component associated with AD pathogenesis, which is derived from the amyloid precursor protein (APP) cleavage. Recent studies suggest that synaptic activity is one of the most important factors that regulate Aβ levels. It has been found that synaptic activity facilitates APP internalization and influences APP cleavage. Glutamatergic, cholinergic, serotonergic, leptin, adrenergic, orexin, and gamma-amino butyric acid receptors, as well as the activity-regulated cytoskeleton-associated protein (Arc) are all involved in these processes. The present review summarizes the evidence for synaptic activity-modulated Aβ levels and the mechanisms underlying this regulation. Interestingly, the immediate early gene product Arc may also be the downstream signaling molecule of several receptors in the synaptic activity-modulated Aβ levels. Elucidating how Aβ levels are regulated by synaptic activity may provide new insights in both the understanding of the pathogenesis of AD and in the development of therapies to slow down the progression of AD.
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Affiliation(s)
- Xiaofang Cheng
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Jian Wu
- Department of Physiology, Third Military Medical University, Chongqing, China
| | - Miao Geng
- Institute of Geriatrics, General Hospital of Chinese PLA, Beijing, China
| | - Jiaxiang Xiong
- Department of Physiology, Third Military Medical University, Chongqing, China.
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Comparison of frailty of primary neurons, embryonic, and aging mouse cortical layers. Neurobiol Aging 2013; 35:322-30. [PMID: 24011540 DOI: 10.1016/j.neurobiolaging.2013.08.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 05/02/2013] [Accepted: 08/05/2013] [Indexed: 11/23/2022]
Abstract
Superficial layers I to III of the human cerebral cortex are more vulnerable toward Aβ peptides than deep layers V to VI in aging. Three models of layers were used to investigate this pattern of frailty. First, primary neurons from E14 and E17 embryonic murine cortices, corresponding respectively to future deep and superficial layers, were treated either with Aβ(1-42), okadaic acid, or kainic acid. Second, whole E14 and E17 embryonic cortices, and third, in vitro separated deep and superficial layers of young and old C57BL/6J mice, were treated identically. We observed that E14 and E17 neurons in culture were prone to death after the Aβ and particularly the kainic acid treatment. This was also the case for the superficial layers of the aged cortex, but not for the embryonic, the young cortex, and the deep layers of the aged cortex. Thus, the aged superficial layers appeared to be preferentially vulnerable against Aβ and kainic acid. This pattern of vulnerability corresponds to enhanced accumulation of senile plaques in the superficial cortical layers with aging and Alzheimer's disease.
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Neuroprotective effects of edaravone on cognitive deficit, oxidative stress and tau hyperphosphorylation induced by intracerebroventricular streptozotocin in rats. Neurotoxicology 2013; 38:136-45. [PMID: 23932983 DOI: 10.1016/j.neuro.2013.07.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 07/16/2013] [Accepted: 07/19/2013] [Indexed: 12/19/2022]
Abstract
Oxidative stress is implicated as an important factor in the development of Alzheimer's disease (AD). In the present study, we have investigated the effects of edaravone (9mg/kg, 3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger, in a streptozotocin (STZ-3mg/kg) induced rat model of sporadic AD (sAD). Treatment with edaravone significantly improved STZ-induced cognitive damage as evaluated in Morris water maze and step-down tests and markedly restored changes in malondialdehyde (MDA), 4-hydroxy-2-nonenal (4-HNE) adducts, hydroxyl radical (OH), hydrogen peroxide (H2O2), total superoxide dismutase (T-SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and protein carbonyl (PC) levels. In addition, histomorphological observations confirmed the protective effect of edaravone on neuronal degeneration. Moreover, hyperphosphorylation of tau resulting from intracerebroventricular streptozotocin (ICV-STZ) injection was decreased by the administration of edaravone. These results provide experimental evidence demonstrating preventive effects of edaravone on cognitive dysfunction, oxidative stress and hyperphosphorylation of tau in ICV-STZ rats. Since edaravone has been used for treatment of patients with stroke, it represents a safe and established therapeutic intervention that has the potential for a novel application in the treatment of age-related neurodegenerative disorders associated with cognitive decline, such as AD.
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Ehresman C. From rendering to remembering: Art therapy for people with Alzheimer's disease. INTERNATIONAL JOURNAL OF ART THERAPY 2013. [DOI: 10.1080/17454832.2013.819023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Jansen D, Zerbi V, Janssen CIF, van Rooij D, Zinnhardt B, Dederen PJ, Wright AJ, Broersen LM, Lütjohann D, Heerschap A, Kiliaan AJ. Impact of a multi-nutrient diet on cognition, brain metabolism, hemodynamics, and plasticity in apoE4 carrier and apoE knockout mice. Brain Struct Funct 2013; 219:1841-68. [PMID: 23832599 DOI: 10.1007/s00429-013-0606-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/24/2013] [Indexed: 11/28/2022]
Abstract
Lipid metabolism and genetic background together strongly influence the development of both cardiovascular and neurodegenerative diseases like Alzheimer's disease (AD). A non-pharmacological way to prevent the genotype-induced occurrence of these pathologies is given by dietary behavior. In the present study, we tested the effects of long-term consumption of a specific multi-nutrient diet in two models for atherosclerosis and vascular risk factors in AD: the apolipoprotein ε4 (apoE4) and the apoE knockout (apoE ko) mice. This specific multi-nutrient diet was developed to support neuronal membrane synthesis and was expected to contribute to the maintenance of vascular health. At 12 months of age, both genotypes showed behavioral changes compared to control mice and we found increased neurogenesis in apoE ko mice. The specific multi-nutrient diet decreased anxiety-related behavior in the open field, influenced sterol composition in serum and brain tissue, and increased the concentration of omega-3 fatty acids in the brain. Furthermore, we found that wild-type and apoE ko mice fed with this multi-nutrient diet showed locally increased cerebral blood volume and decreased hippocampal glutamate levels. Taken together, these data suggest that a specific dietary intervention has beneficial effects on early pathological consequences of hypercholesterolemia and vascular risk factors for AD.
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Affiliation(s)
- Diane Jansen
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, PO Box 9101, 6500 HB, Nijmegen, The Netherlands,
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36
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Compensating for synaptic loss in Alzheimer’s disease. J Comput Neurosci 2013; 36:19-37. [DOI: 10.1007/s10827-013-0462-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 05/10/2013] [Accepted: 05/14/2013] [Indexed: 01/08/2023]
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Jansen D, Zerbi V, Janssen CIF, Dederen PJWC, Mutsaers MPC, Hafkemeijer A, Janssen AL, Nobelen CLM, Veltien A, Asten JJ, Heerschap A, Kiliaan AJ. A longitudinal study of cognition, proton MR spectroscopy and synaptic and neuronal pathology in aging wild-type and AβPPswe-PS1dE9 mice. PLoS One 2013; 8:e63643. [PMID: 23717459 PMCID: PMC3661598 DOI: 10.1371/journal.pone.0063643] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Accepted: 04/04/2013] [Indexed: 11/24/2022] Open
Abstract
Proton magnetic resonance spectroscopy (1H MRS) is a valuable tool in Alzheimer’s disease research, investigating the functional integrity of the brain. The present longitudinal study set out to characterize the neurochemical profile of the hippocampus, measured by single voxel 1H MRS at 7 Tesla, in the brains of AβPPSswe-PS1dE9 and wild-type mice at 8 and 12 months of age. Furthermore, we wanted to determine whether alterations in hippocampal metabolite levels coincided with behavioral changes, cognitive decline and neuropathological features, to gain a better understanding of the underlying neurodegenerative processes. Moreover, correlation analyses were performed in the 12-month-old AβPP-PS1 animals with the hippocampal amyloid-β deposition, TBS-T soluble Aβ levels and high-molecular weight Aβ aggregate levels to gain a better understanding of the possible involvement of Aβ in neurochemical and behavioral changes, cognitive decline and neuropathological features in AβPP-PS1 transgenic mice. Our results show that at 8 months of age AβPPswe-PS1dE9 mice display behavioral and cognitive changes compared to age-matched wild-type mice, as determined in the open field and the (reverse) Morris water maze. However, there were no variations in hippocampal metabolite levels at this age. AβPP-PS1 mice at 12 months of age display more severe behavioral and cognitive impairment, which coincided with alterations in hippocampal metabolite levels that suggest reduced neuronal integrity. Furthermore, correlation analyses suggest a possible role of Aβ in inflammatory processes, synaptic dysfunction and impaired neurogenesis.
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Affiliation(s)
- Diane Jansen
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Valerio Zerbi
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Carola I. F. Janssen
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Pieter J. W. C. Dederen
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Martina P. C. Mutsaers
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Anne Hafkemeijer
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Anna-Lena Janssen
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Cindy L. M. Nobelen
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
| | - Andor Veltien
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Jack J. Asten
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Arend Heerschap
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Amanda J. Kiliaan
- Department of Anatomy, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Neuroscience, Nijmegen, The Netherlands
- * E-mail:
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Yates SC, Zafar A, Hubbard P, Nagy S, Durant S, Bicknell R, Wilcock G, Christie S, Esiri MM, Smith AD, Nagy Z. Dysfunction of the mTOR pathway is a risk factor for Alzheimer's disease. Acta Neuropathol Commun 2013; 1:3. [PMID: 24252508 PMCID: PMC3776211 DOI: 10.1186/2051-5960-1-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 01/17/2013] [Indexed: 11/17/2022] Open
Abstract
Background The development of disease-modifying therapies for Alzheimer’s disease is hampered by our lack of understanding of the early pathogenic mechanisms and the lack of early biomarkers and risk factors. We have documented the expression pattern of mTOR regulated genes in the frontal cortex of Alzheimer’s disease patients. We have also examined the functional integrity of mTOR signaling in peripheral lymphocytes in Alzheimer’s disease patients relative to healthy controls. Results In the brain mTOR is seen to control molecular functions related to cell cycle regulation, cell death and several metabolic pathways. These downstream elements of the mTOR signaling cascade are deregulated in the brain of Alzheimer’s disease patients well before the development of pathology. This dysregulation of the mTOR downstream signaling cascade is not restricted to the brain but appears to be systemic and can be detected in peripheral lymphocytes as a reduced Rapamycin response. Conclusions The dysfunction of the signaling pathways downstream of mTOR may represent a risk factor for Alzheimer’s disease and is independent of the ApoE status of the patients. We have also identified the molecular substrates of the beneficial effects of Rapamycin on the nervous system. We believe that these results can further inform the development of clinical predictive tests for the risk of Alzheimer’s disease in patients with mild cognitive impairment.
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Synaptic Proteins and Choline Acetyltransferase Loss in Visual Cortex in Dementia With Lewy Bodies. J Neuropathol Exp Neurol 2013; 72:53-60. [DOI: 10.1097/nen.0b013e31827c5710] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Crimins JL, Rocher AB, Luebke JI. Electrophysiological changes precede morphological changes to frontal cortical pyramidal neurons in the rTg4510 mouse model of progressive tauopathy. Acta Neuropathol 2012; 124:777-95. [PMID: 22976049 DOI: 10.1007/s00401-012-1038-9] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 08/20/2012] [Accepted: 08/21/2012] [Indexed: 12/14/2022]
Abstract
Whole-cell patch-clamp recordings and high-resolution morphometry were used to assess functional and structural properties of layer 3 pyramidal neurons in early (<4 months) and advanced (>8 months) stages of tauopathy in frontal cortical slices prepared from rTg4510 tau mutant (P301L) mice. In early tauopathy, dendritic architecture is preserved. In advanced tauopathy, neurons can be categorized as either "atrophic" (58 %)-exhibiting marked atrophy of the apical tuft, or "intact" (42 %)-with normal apical tufts and, in some instances, proliferative sprouting of oblique branches of the apical trunk. Approximately equal numbers of atrophic and intact neurons contain neurofibrillary tangles (NFTs) or are tangle-free, lending further support to the idea that NFTs per se are not toxic. Spine density is decreased due to a specific reduction in mushroom spines, but filopodia are increased in both atrophic and intact neurons. By contrast to these morphological changes, which are robust only in the advanced stage, significant electrophysiological changes are present in the early stage and persist in the advanced stage in both atrophic and intact neurons. The most marked of these changes are: a depolarized resting membrane potential, an increased depolarizing sag potential and increased action potential firing rates-all indicative of hyperexcitability. Spontaneous excitatory postsynaptic currents are not reduced in frequency or amplitude in either stage. The difference in the time course of functionally important electrophysiological changes versus regressive morphological changes implies differences in pathogenic mechanisms underlying functional and structural changes to neurons during progressive tauopathy.
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Affiliation(s)
- Johanna L Crimins
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA
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Reverte I, Klein AB, Ratner C, Domingo JL, Colomina MT. Behavioral phenotype and BDNF differences related to apoE isoforms and sex in young transgenic mice. Exp Neurol 2012; 237:116-25. [DOI: 10.1016/j.expneurol.2012.06.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 06/14/2012] [Accepted: 06/16/2012] [Indexed: 02/07/2023]
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Khan MB, Khan MM, Khan A, Ahmed ME, Ishrat T, Tabassum R, Vaibhav K, Ahmad A, Islam F. Naringenin ameliorates Alzheimer's disease (AD)-type neurodegeneration with cognitive impairment (AD-TNDCI) caused by the intracerebroventricular-streptozotocin in rat model. Neurochem Int 2012; 61:1081-93. [PMID: 22898296 DOI: 10.1016/j.neuint.2012.07.025] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 07/27/2012] [Accepted: 07/31/2012] [Indexed: 11/17/2022]
Abstract
Oxidative stress is involved in Alzheimer's disease (AD)-type neurodegeneration with cognitive impairment (AD-TNDCI) as well as age related cognitive deficit. The present study was designed to investigate the pre-treatment effects of naringenin (NAR), a polyphenolic compound on cognitive dysfunction, oxidative stress in the hippocampus, and hippocampal neuron injury in a rat model of AD-TNDCI. The rats were pre-treated with NAR at a selective dose (50mg/kg, orally) for 2 weeks followed by intracerebroventricular-streptozotocin (ICV-STZ) (3mg/kg; 5μl per site) injection bilaterally. Behavioral alterations were monitored after 2 weeks from the lesion using passive avoidance test and Morris water maze paradigm. Three weeks after the lesion, the rats were sacrificed for measuring non-enzymatic [4-hydroxynonenal (4-HNE), malonaldehyde (MDA), thiobarbituric reactive substances (TBARS), hydrogen peroxide (H(2)O(2)), protein carbonyl (PC), reduced glutathione (GSH)] content and enzymatic [glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) and Na(+)/K(+)-ATPase] activity in the hippocampus, and expression of choline acetyltransferase (ChAT) positive neuron, and histopathology of hippocampal neurons. The non-enzymatic level and enzymatic activity was significantly increased and decreased, respectively, with striking impairments in spatial learning and memory, loss of ChAT positive neuron and severe damage to hippocampal neurons in the rat induced by ICV-STZ. These abnormalities were significantly improved by NAR pre-treatment. The study suggests that NAR can protect against cognitive deficits, neuronal injury and oxidative stress induced by ICV-STZ, and may be used as a potential agent in treatment of neurodegenerative diseases such as AD-TNDCI.
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Affiliation(s)
- M Badruzzaman Khan
- Department of Medical Elementology & Toxicology, Hamdard University, Hamdard Nagar, New Delhi, India.
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Hernández-Ortega K, Arias C. ERK activation and expression of neuronal cell cycle markers in the hippocampus after entorhinal cortex lesion. J Neurosci Res 2012; 90:2116-26. [PMID: 22811014 DOI: 10.1002/jnr.23106] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 05/22/2012] [Accepted: 05/29/2012] [Indexed: 12/22/2022]
Abstract
Current findings suggest that neuronal cell death is frequently associated with the aberrant expression of cell cycle-regulatory proteins in postmitotic neurons. Aberrant cell cycle reentry has been implicated in diverse neurodegenerative conditions, including Alzheimer's disease (AD). Previously we reported that the appearance of cell cycle markers in postmitotic neurons of the entorhinal cortex (EC) after excitotoxic hippocampal damage is associated with the expression of phospho-tau and amyloid precursor protein (APP). However, the question of the signaling pathway involved in this cell cycle reentry remains unresolved. Differentiated neurons use the molecular mechanisms initially acquired to direct cell proliferation, such as the Ras-extracellular signal-regulated kinase (ERK1/2) pathway, to regulate synaptic plasticity. In this work we explored whether ERK1/2-related signaling might contribute to the cell cycle reentry in hippocampal neurons after a unilateral EC lesion. We showed that, within the first 24 hr after hippocampal deafferentation, numerous neurons expressed phospho-ERK1/2, concomitantly with the gradual increases in cyclin D1 and cyclin B immunoreactivity in the dentate gyrus and hilus. Several of these immunopositive cells to phospho-ERK1/2 and cyclin B in hippocampus are postmitotic neurons, insofar as they are positive to NeuN. The intracisternal administration of U0126 (an MEK inhibitor), previous to the excitotoxic lesion, decreased the activation of ERK1/2 and the expression of cyclin D1 and cyclin B in the hippocampus. The present findings support the notion that ERK1/2 plays a role in cell cycle reactivation in mature neurons efferently connected to the lesion site.
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Affiliation(s)
- Karina Hernández-Ortega
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México D.F., México
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Cell cycle activation and aneuploid neurons in Alzheimer's disease. Mol Neurobiol 2012; 46:125-35. [PMID: 22528601 DOI: 10.1007/s12035-012-8262-0] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 03/20/2012] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disorder, characterized by synaptic degeneration associated with fibrillar aggregates of the amyloid-ß peptide and the microtubule-associated protein tau. The progression of neurofibrillary degeneration throughout the brain during AD follows a predictive pattern which provides the basis for the neuropathological staging of the disease. This pattern of selective neuronal vulnerability against neurofibrillary degeneration matches the regional degree of neuronal plasticity and inversely recapitulates ontogenetic and phylogenetic brain development which links neurodegenerative cell death to neuroplasticity and brain development. Here, we summarize recent evidence for a loss of neuronal differentiation control as a critical pathogenetic event in AD, associated with a reactivation of the cell cycle and a partial or full replication of DNA giving rise to neurons with a content of DNA above the diploid level. Neurons with an aneuploid set of chromosomes are also present at a low frequency in the normal brain where they appear to be well tolerated. In AD, however, where the number of aneuploid neurons is highly increased, a rather selective cell death of neurons with this chromosomal aberrancy occurs. This finding add aneuploidy to the list of critical molecular events that are shared between neurodegeneration and oncogenesis. It defines a molecular signature for neuronal vulnerability and directs our attention to a failure of neuronal differentiation control as a critical pathogenetic event and potential therapeutic target in AD.
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Sontag JM, Nunbhakdi-Craig V, White CL, Halpain S, Sontag E. The protein phosphatase PP2A/Bα binds to the microtubule-associated proteins Tau and MAP2 at a motif also recognized by the kinase Fyn: implications for tauopathies. J Biol Chem 2012; 287:14984-93. [PMID: 22403409 DOI: 10.1074/jbc.m111.338681] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The predominant brain microtubule-associated proteins MAP2 and tau play a critical role in microtubule cytoskeletal organization and function. We have previously reported that PP2A/Bα, a major protein phosphatase 2A (PP2A) holoenzyme, binds to and dephosphorylates tau, and regulates microtubule stability. Here, we provide evidence that MAP2 co-purifies with and is dephosphorylated by endogenous PP2A/Bα in bovine gray matter. It co-localizes with PP2A/Bα in immature and mature human neuronal cell bodies. PP2A co-immunoprecipitates with and directly interacts with MAP2. Using in vitro binding assays, we show that PP2A/Bα binds to MAP2c isoforms through a region encompassing the microtubule-binding domain and upstream proline-rich region. Tau and MAP2 compete for binding to and dephosphorylation by PP2A/Bα. Remarkably, the protein-tyrosine kinase Fyn, which binds to the proline-rich RTPPKSP motif conserved in both MAP2 and tau, inhibits the interaction of PP2A/Bα with either tau or MAP2c. The corresponding synthetic RTPPKSP peptide, but not the phosphorylated RpTPPKSP version, competes with Tau and MAP2c for binding to PP2A/Bα. Significantly, down-regulation of PP2A/Bα and deregulation of Fyn-Tau protein interactions have been linked to enhanced tau phosphorylation in Alzheimer disease. Together, our results suggest that PP2A/Bα is part of segregated MAP2 and tau signaling scaffolds that can coordinate the action of key kinases and phosphatases involved in modulating neuronal plasticity. Deregulation of these compartmentalized multifunctional protein complexes is likely to contribute to tau deregulation, microtubule disruption, and altered signaling in tauopathies.
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Affiliation(s)
- Jean-Marie Sontag
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales 2308, Australia
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Sharma V, Bala A, Deshmukh R, Bedi KL, Sharma PL. Neuroprotective effect of RO-20-1724-a phosphodiesterase4 inhibitor against intracerebroventricular streptozotocin induced cognitive deficit and oxidative stress in rats. Pharmacol Biochem Behav 2012; 101:239-45. [PMID: 22285388 DOI: 10.1016/j.pbb.2012.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2011] [Revised: 11/21/2011] [Accepted: 01/06/2012] [Indexed: 01/06/2023]
Abstract
Cyclic nucleotides viz cGMP and cAMP are known to play an important role in learning and memory processes. Enhancement of cyclic nucleotide signalling through inhibition of phosphodiesterases (PDEs) has been reported to be beneficial in several neurodegenerative disorders associated with cognitive decline. The present study was undertaken to investigate the effect of RO-20-1724-a PDE4 inhibitor on streptozotocin (STZ) induced experimental sporadic dementia of Alzheimer's type. The STZ was injected twice intracerebroventrically (3 mg/kg i.c.v.) on alternate days (day 1 and day 3) in rats. The STZ injected rats were treated with RO-20-1724 (125, 250 and 500 μg/kgi.p.) for 21 days following first i.c.v. STZ administration. Learning and memory in rats were assessed by passive avoidance [PA (days 14 and 15)] and Morris water maze [MWM (days 17, 18, 19, 20 and 21)] following first i.c.v. STZ administration. On day 22 rat cerebral homogenate was used for all the biochemical estimations. The pharmacological inhibition of PDE4 by RO-20-1724 significantly attenuated STZ induced cognitive deficit and oxidative stress. RO-20-1724 was found to not only improve learning and memory in MWM and PA paradigms but also restore STZ induced elevation in cholinesterase activity. Further, RO-20-1724 significantly reduced malondialdehyde and nitrite levels, and restored the glutathione levels indicating attenuation of oxidative stress. Current data complement previous studies by providing evidence for a subset of cognition enhancing effects after PDE4 inhibition. The observed beneficial effects of RO-20-1724 in spatial memory may be due to its ability to restore cholinergic functions and possibly through its antioxidant mechanisms.
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Affiliation(s)
- Vivek Sharma
- Neuropharmacology Div., Department of Pharmacology, ISF College of Pharmacy, Moga-142001, Punjab, India
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BACE1 elevation is associated with aberrant limbic axonal sprouting in epileptic CD1 mice. Exp Neurol 2012; 235:228-37. [PMID: 22265658 DOI: 10.1016/j.expneurol.2012.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 12/25/2011] [Accepted: 01/04/2012] [Indexed: 12/20/2022]
Abstract
The brain is capable of remarkable synaptic reorganization following stress and injury, often using the same molecular machinery that governs neurodevelopment. This form of plasticity is crucial for restoring and maintaining network function. However, neurodegeneration and subsequent reorganization can also play a role in disease pathogenesis, as is seen in temporal lobe epilepsy and Alzheimer's disease. β-Secretase-1 (BACE1) is a protease known for cleaving β-amyloid precursor protein into β-amyloid (Aβ), a major constituent in amyloid plaques. Emerging evidence suggests that BACE1 is also involved with synaptic plasticity and nerve regeneration. Here we examined whether BACE1 immunoreactivity (IR) was altered in pilocarpine-induced epileptic CD1 mice in a manner consistent with the synaptic reorganization seen during epileptogenesis. BACE1-IR increased in the CA3 mossy fiber field and dentate inner molecular layer in pilocarpine-induced epileptic mice, relative to controls (saline-treated mice and mice 24-48 h after pilocarpine-status), and paralleled aberrant expression of neuropeptide Y. Regionally increased BACE1-IR also occurred in neuropil in hippocampal area CA1 and in subregions of the amygdala and temporal cortex in epileptic mice, colocalizing with increased IR for growth associated protein 43 (GAP43) and polysialylated-neural cell adhesion molecule (PSA-NCAM), but reduced IR for microtubule-associated protein 2 (MAP2). These findings suggest that BACE1 is involved in aberrant limbic axonal sprouting in a model of temporal lobe epilepsy, warranting further investigation into the role of BACE1 in physiological vs. pathological neuronal plasticity.
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Neill D. Should Alzheimer's disease be equated with human brain ageing? A maladaptive interaction between brain evolution and senescence. Ageing Res Rev 2012; 11:104-22. [PMID: 21763787 DOI: 10.1016/j.arr.2011.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/26/2011] [Accepted: 06/28/2011] [Indexed: 10/18/2022]
Abstract
In this review Alzheimer's disease is seen as a maladaptive interaction between human brain evolution and senescence. It is predicted to occur in everyone although does not necessarily lead to dementia. The pathological process is initiated in relation to a senescence mediated functional down-regulation in the posteromedial cortex (Initiation Phase). This leads to a loss of glutamatergic excitatory input to layer II entorhinal cortex neurons. A human specific maladaptive neuroplastic response is initiated in these neurons leading to neuronal dysfunction, NFT formation and death. This leads to further loss of glutamatergic excitatory input and propagation of the maladaptive response along excitatory pathways linking evolutionary progressed vulnerable neurons (Propagation Phase). Eventually neurons are affected in many brain areas resulting in dementia. Possible therapeutic approaches include enhancing glutamatergic transmission. The theory may have implications with regards to how Alzheimer's disease is classified.
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Gomi F, Uchida Y. MAP1B 1–126 interacts with tubulin isoforms and induces neurite outgrowth and neuronal death of cultured cortical neurons. Brain Res 2012; 1433:1-8. [DOI: 10.1016/j.brainres.2011.11.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 10/12/2011] [Accepted: 11/11/2011] [Indexed: 01/11/2023]
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New pyrazolyl and thienyl aminohydantoins as potent BACE1 inhibitors: exploring the S2' region. Bioorg Med Chem Lett 2011; 21:5164-70. [PMID: 21835615 DOI: 10.1016/j.bmcl.2011.07.057] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 07/13/2011] [Accepted: 07/14/2011] [Indexed: 11/23/2022]
Abstract
The proteolytic enzyme β-secretase (BACE1) plays a central role in the synthesis of the pathogenic β-amyloid in Alzheimer's disease. SAR studies of the S2' region of the BACE1 ligand binding pocket with pyrazolyl and thienyl P2' side chains are reported. These analogs exhibit low nanomolar potency for BACE1, and demonstrate >50- to 100-fold selectivity for the structurally related aspartyl proteases BACE2 and cathepsin D. Small groups attached at the nitrogen of the P2' pyrazolyl moiety, together with the P3 pyrimidine nucleus projecting into the S3 region of the binding pocket, are critical components to ligand's potency and selectivity. P2' thiophene side chain analogs are highly potent BACE1 inhibitors with excellent selectivity against cathepsin D, but only modest selectivity against BACE2. The cell-based activity of these new analogs tracked well with their increased molecular binding with EC(50) values of 0.07-0.2 μM in the ELISA assay for the most potent analogs.
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