1
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Liu Y, Chen Y, Fukui K. Oxidative stress induces tau hyperphosphorylation via MARK activation in neuroblastoma N1E-115 cells. J Clin Biochem Nutr 2023; 73:24-33. [PMID: 37534088 PMCID: PMC10390814 DOI: 10.3164/jcbn.22-39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 12/28/2022] [Indexed: 08/04/2023] Open
Abstract
Reactive oxygen species are considered a cause of neuronal cell death in Alzheimer's disease (AD). Abnormal tau phosphorylation is a proven pathological hallmark of AD. Microtubule affinity-regulating kinases (MARKs) regulate tau-microtubule binding and play a crucial role in neuronal survival. In this study, we hypothesized that oxidative stress increases the phosphorylation of Ser262 of tau protein through activation of MARKs, which is the main reason for the development of AD. We investigated the relationship between tau hyperphosphorylation on Ser262 and MARKs in N1E-115 cells subjected to oxidative stress by exposure to a low concentration of hydrogen peroxide. This work builds on the observation that hyperphosphorylation of tau is significantly increased by oxidative stress. MARKs activation correlated with tau hyperphosphorylation at Ser262, a site that is essential to maintain microtubule stability and is the initial phosphorylation site in AD. These results indicated that MARKs inhibitors might serve a role as therapeutic tools for the treatment of AD.
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Affiliation(s)
- Yuhong Liu
- Molecular Cell Biology Laboratory, Department of Functional Control Systems, Graduate School of Engineering and Science, Shibaura Institute of Technology, Fukasaku 307, Minuma-ku, Saitama 337-8570, Japan
| | - Yunxi Chen
- Molecular Cell Biology Laboratory, Department of Systems Engineering and Science, School of Engineering and Science, Shibaura Institute of Technology, Fukasaku 307, Minuma-ku, Saitama 337-8570, Japan
| | - Koji Fukui
- Molecular Cell Biology Laboratory, Department of Functional Control Systems, Graduate School of Engineering and Science, Shibaura Institute of Technology, Fukasaku 307, Minuma-ku, Saitama 337-8570, Japan
- Molecular Cell Biology Laboratory, Department of Systems Engineering and Science, School of Engineering and Science, Shibaura Institute of Technology, Fukasaku 307, Minuma-ku, Saitama 337-8570, Japan
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2
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Qu M, Zuo L, Zhang M, Cheng P, Guo Z, Yang J, Li C, Wu J. High glucose induces tau hyperphosphorylation in hippocampal neurons via inhibition of ALKBH5-mediated Dgkh m 6A demethylation: a potential mechanism for diabetic cognitive dysfunction. Cell Death Dis 2023; 14:385. [PMID: 37385994 PMCID: PMC10310746 DOI: 10.1038/s41419-023-05909-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 06/02/2023] [Accepted: 06/19/2023] [Indexed: 07/01/2023]
Abstract
Tau hyperphosphorylation in hippocampal neurons has an important pathogenetic role in the development of diabetic cognitive dysfunction. N6-methyladenosine (m6A) methylation is the most common modification of eukaryotic mRNA and is involved in regulating diverse biological processes. However, the role of m6A alteration in tau hyperphosphorylation of hippocampus neurons has not been reported. We found lower ALKBH5 expression in the hippocampus of diabetic rats and in HN-h cells with high-glucose intervention, accompanied by tau hyperphosphorylation. ALKBH5 overexpression significantly reversed tau hyperphosphorylation in high-glucose-stimulated HN-h cells. Furthermore, we found and confirmed by m6A-mRNA epitope transcriptome microarray and transcriptome RNA sequencing coupled with methylated RNA immunoprecipitation that ALKBH5 regulates the m6A modification of Dgkh mRNA. High glucose inhibited the demethylation modification of Dgkh by ALKBH5, resulting in decreases in Dgkh mRNA and protein levels. Overexpression of Dgkh reversed tau hyperphosphorylation in HN-h cells after high-glucose stimulation. Overexpression of Dgkh by adenovirus suspension injection into the bilateral hippocampus of diabetic rats significantly ameliorated tau hyperphosphorylation and diabetic cognitive dysfunction. In addition, ALKBH5 targeted Dgkh to activate PKC-α, leading to tau hyperphosphorylation under high-glucose conditions. The results of this study reveal that high glucose suppresses the demethylation modification of Dgkh by ALKBH5, which downregulates Dgkh and leads to tau hyperphosphorylation through activation of PKC-α in hippocampal neurons. These findings may indicate a new mechanism and a novel therapeutic target for diabetic cognitive dysfunction.
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Affiliation(s)
- Minli Qu
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Linhui Zuo
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Mengru Zhang
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Peng Cheng
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhanjun Guo
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Junya Yang
- School of Health and Related Research, University of Sheffield, Sheffield, UK
| | - Changjun Li
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Endocrinology Research Center, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jing Wu
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- Hunan Engineering Research Center for Obesity and its Metabolic Complications, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.
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3
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Susmitha G, Kumar R. Role of microbial dysbiosis in the pathogenesis of Alzheimer's disease. Neuropharmacology 2023; 229:109478. [PMID: 36871788 DOI: 10.1016/j.neuropharm.2023.109478] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/08/2023] [Accepted: 02/23/2023] [Indexed: 03/07/2023]
Abstract
Alzheimer's disease (AD) is the leading cause of dementia in the elderly and detected during the advanced stages where the chances of reversal are minimum. The gut-brain axis mediates a bidirectional communication between the gut and brain, which is dependent on bacterial products such as short chain fatty acids (SCFA) and neurotransmitters. Accumulating lines of evidence suggests that AD is associated with significant alteration in the composition of gut microbiota. Furthermore, transfer of gut microbiota from healthy individuals to patients can reshape the gut microbiota structure and thus holds the potential to be exploited for the treatment of various neurodegenerative disease. Moreover, AD-associated gut dysbiosis can be partially reversed by using probiotics, prebiotics, natural compounds and dietary modifications, but need further validations. Reversal of AD associated gut dysbiosis alleviate AD-associated pathological feature and therefore can be explored as a therapeutic approach in the future. The current review article will describe various studies suggesting that AD dysbiosis occurs with AD and highlights the causal role by focussing on the interventions that hold the potential to reverse the gut dysbiosis partially.
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Affiliation(s)
- Gudimetla Susmitha
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Vishakhapatnam, India
| | - Rahul Kumar
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Vishakhapatnam, India.
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4
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Chen Y, Lu H, Ding Y, Liu S, Ding Y, Lu B, Xiao J, Zhou X. Dietary Protective Potential of Fucoxanthin as an Active Food Component on Neurological Disorders. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:3599-3619. [PMID: 36802555 DOI: 10.1021/acs.jafc.2c08249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The prevalence of neurodegenerative, cerebrovascular, and psychiatric diseases and other neurological disorders has increased dramatically worldwide. Fucoxanthin is an algal pigment with many biological functions, and there is rising evidence that fucoxanthin plays a preventive and therapeutic role in neurological disorders. This review focuses on the metabolism, bioavailability, and blood-brain barrier penetration of fucoxanthin. Furthermore, the neuroprotective potential of fucoxanthin in neurodegenerative diseases, cerebrovascular diseases, and psychiatric diseases as well as other neurological disorders such as epilepsy, neuropathic pain, and brain tumors by acting on multiple targets will be summarized. The multiple targets include regulating apoptosis, reducing oxidative stress, activating the autophagy pathway, inhibiting Aβ aggregation, improving dopamine secretion, reducing α-synuclein aggregation, attenuating neuroinflammation, modulating gut microbiota, and activating brain-derived neurotrophic factor, etc. Additionally, we look forward to brain-targeted oral transport systems due to the low bioavailability and blood-brain barrier permeability of fucoxanthin. We also propose exploring the systemic mechanisms of fucoxanthin metabolism and transport through the gut-brain process and envision new therapeutic targets for fucoxanthin to act on the central nervous system. Finally, we propose dietary fucoxanthin delivery interventions to achieve preventive effects on neurological disorders. This review provides a reference for the application of fucoxanthin in the neural field.
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Affiliation(s)
- Yufeng Chen
- College of Food Science and Technology, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, National R&D Branch Center for Pelagic Aquatic Products Processing, Zhejiang University of Technology, Hangzhou 310014, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
| | - Hao Lu
- College of Food Science and Technology, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, National R&D Branch Center for Pelagic Aquatic Products Processing, Zhejiang University of Technology, Hangzhou 310014, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
| | - Yicheng Ding
- College of Food Science and Technology, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, National R&D Branch Center for Pelagic Aquatic Products Processing, Zhejiang University of Technology, Hangzhou 310014, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
| | - Shulai Liu
- College of Food Science and Technology, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, National R&D Branch Center for Pelagic Aquatic Products Processing, Zhejiang University of Technology, Hangzhou 310014, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
| | - Yuting Ding
- College of Food Science and Technology, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, National R&D Branch Center for Pelagic Aquatic Products Processing, Zhejiang University of Technology, Hangzhou 310014, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
| | - Baiyi Lu
- College of Biosystems Engineering and Food Science, Key Laboratory for Agro-Products Nutritional Evaluation of Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou 310058, China
| | - Jianbo Xiao
- Nutrition and Bromatology Group, Department of Analytical Chemistry and Food Science, Faculty of Food Science and Technology, University of Vigo-Ourense Campus, E-32004 Ourense, Spain
| | - Xuxia Zhou
- College of Food Science and Technology, Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, National R&D Branch Center for Pelagic Aquatic Products Processing, Zhejiang University of Technology, Hangzhou 310014, China
- Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
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5
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Hu Z, Chen PH, Li W, Douglas T, Hines J, Liu Y, Crews CM. Targeted Dephosphorylation of Tau by Phosphorylation Targeting Chimeras (PhosTACs) as a Therapeutic Modality. J Am Chem Soc 2023; 145:4045-4055. [PMID: 36753634 DOI: 10.1021/jacs.2c11706] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Microtubule-associated protein tau is essential for microtubule assembly and stabilization. Hyperphosphorylation of the microtubule-associated protein tau plays an important pathological role in the development of Alzheimer's disease and other tauopathies. In vivo studies using kinase inhibitors suggest that reducing tau phosphorylation levels has therapeutic potential; however, such approaches showed limited benefits. We sought to further develop our phosphorylation targeting chimera (PhosTAC) technology to specifically induce tau dephosphorylation. Herein, we use small molecule-based PhosTACs to recruit tau to PP2A, a native tau phosphatase. PhosTACs induced the formation of a stable ternary complex, leading to rapid, efficient, and sustained tau dephosphorylation, which also correlated with the enhanced downregulation of tau protein. Mass spectrometry data validated that PhosTACs downregulated multiple phosphorylation sites of tau. We believe that PhosTAC possesses several advantages over current strategies to modulate tau phosphorylation and represents a new avenue for disease-modifying therapies for tauopathies.
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Affiliation(s)
- Zhenyi Hu
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06511, United States
| | - Po-Han Chen
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06511, United States
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan City 701, Taiwan
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan city 701, Taiwan
| | - Wenxue Li
- Yale Cancer Biology Institute, West Haven, Connecticut 06516, United States
| | - Todd Douglas
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06511, United States
| | - John Hines
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06511, United States
| | - Yansheng Liu
- Yale Cancer Biology Institute, West Haven, Connecticut 06516, United States
| | - Craig M Crews
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06511, United States
- Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
- Department of Pharmacology, Yale University, New Haven, Connecticut 06511, United States
- Yale University School of Medicine, New Haven, Connecticut 06511, United States
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6
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Quach TT, Stratton HJ, Khanna R, Mackey-Alfonso S, Deems N, Honnorat J, Meyer K, Duchemin AM. Neurodegenerative Diseases: From Dysproteostasis, Altered Calcium Signalosome to Selective Neuronal Vulnerability to AAV-Mediated Gene Therapy. Int J Mol Sci 2022; 23:ijms232214188. [PMID: 36430666 PMCID: PMC9694178 DOI: 10.3390/ijms232214188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/01/2022] [Accepted: 11/04/2022] [Indexed: 11/18/2022] Open
Abstract
Despite intense research into the multifaceted etiology of neurodegenerative diseases (ND), they remain incurable. Here we provide a brief overview of several major ND and explore novel therapeutic approaches. Although the cause (s) of ND are not fully understood, the accumulation of misfolded/aggregated proteins in the brain is a common pathological feature. This aggregation may initiate disruption of Ca++ signaling, which is an early pathological event leading to altered dendritic structure, neuronal dysfunction, and cell death. Presently, ND gene therapies remain unidimensional, elusive, and limited to modifying one pathological feature while ignoring others. Considering the complexity of signaling cascades in ND, we discuss emerging therapeutic concepts and suggest that deciphering the molecular mechanisms involved in dendritic pathology may broaden the phenotypic spectrum of ND treatment. An innovative multiplexed gene transfer strategy that employs silencing and/or over-expressing multiple effectors could preserve vulnerable neurons before they are lost. Such therapeutic approaches may extend brain health span and ameliorate burdensome chronic disease states.
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Affiliation(s)
- Tam T. Quach
- Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
- INSERM U1217/CNRS UMR5310, Université de Lyon, Université Claude Bernard Lyon 1, 69677 Lyon, France
| | | | - Rajesh Khanna
- Department of Molecular Pathobiology, New York University, New York, NY 10010, USA
| | - Sabrina Mackey-Alfonso
- Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Nicolas Deems
- Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Jérome Honnorat
- INSERM U1217/CNRS UMR5310, Université de Lyon, Université Claude Bernard Lyon 1, 69677 Lyon, France
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, 69677 Lyon, France
- SynatAc Team, Institut NeuroMyoGène, 69677 Lyon, France
| | - Kathrin Meyer
- The Research Institute of Nationwide Children Hospital, Columbus, OH 43205, USA
- Department of Pediatric, The Ohio State University, Columbus, OH 43210, USA
| | - Anne-Marie Duchemin
- Department of Psychiatry and Behavioral Health, The Ohio State University, Columbus, OH 43210, USA
- Correspondence: ; Tel.: +1-614-293-5517; Fax: +1-614-293-7599
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7
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Ganguly D, Thomas JA, Ali A, Kumar R. Mechanistic and therapeutic implications of EphA-4 receptor tyrosine kinase in the pathogenesis of Alzheimer's disease. Eur J Neurosci 2022; 56:5532-5546. [PMID: 34989046 DOI: 10.1111/ejn.15591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 12/14/2021] [Accepted: 12/28/2021] [Indexed: 12/14/2022]
Abstract
Erythropoietin-producing hepatoma (Eph) receptors belong to a family of tyrosine kinase receptors that plays a pivotal role in the development of the brain. Eph can be divided broadly into two groups, namely, EphA and EphB, comprising nine and five members, respectively. In recent years, the role of EphA-4 has become increasingly apparent in the onset of Alzheimer's disease (AD). Emerging evidence suggests that EphA-4 results in synaptic dysfunction, which in turn promotes the progression of AD. Moreover, pharmacological or genetic ablation of EphA-4 in the murine model of AD can alleviate the symptoms. The current review summarizes different pathways by which EphA-4 can influence pathogenesis. Since, majority of the studies had reported the protective effect of EphA-4 inhibition during AD, designing therapeutics based on decreasing its enzymatic activity might be necessary for introducing the novel interventions. Therefore, the review described peptide and nanobodies inhibitors of EphA-4 that exhibit the potential to modulate EphA-4 and could be used as lead molecules for the targeted therapy of AD.
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Affiliation(s)
- Devargya Ganguly
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Vishakhapatnam, India
| | - Joshua Abby Thomas
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Vishakhapatnam, India
| | - Abid Ali
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Rahul Kumar
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Vishakhapatnam, India
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8
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Bera A, Lavanya G, Reshmi R, Dev K, Kumar R. Mechanistic and therapeutic role of Drp1 in the pathogenesis of Alzheimer's disease. Eur J Neurosci 2022; 56:5516-5531. [PMID: 35078269 DOI: 10.1111/ejn.15611] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/31/2021] [Accepted: 01/13/2022] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD), a progressive neurodegenerative disorder, has emerged as the most common form of dementia in the elderly. Two major pathological hallmarks have been identified for AD: extracellular amyloid plaques and intracellular neurofibrillary tangles (NFT). Recently, dynamin-related protein 1 (Drp1) was recognized to contribute significantly towards the pathogenesis of AD. Drp1 is primarily located in the cytosol, from where it translocates to the mitochondrial outer membrane and drives the mitochondrial fission via GTP hydrolysis. Drp1 interacts with Aβ and phosphorylated tau, leading to excessive mitochondrial fragmentation, which in turn results in synaptic dysfunction, neuronal damage and cognitive decline. Several studies suggest an increase in the level of Drp1 in the post-mortem brain specimen collected from the AD patients and murine models of AD. Interestingly, heterozygous deletion of Drp1 in the transgenic murine model of AD ameliorates the mitochondrial dysfunction, improving learning and memory. The current review article discusses the possible mechanistic pathways by which Drp1 can influence the pathogenesis of AD. Besides, it will describe various inhibitors for Drp1 and their potential role as therapeutics for AD in the future.
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Affiliation(s)
- Arpita Bera
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Visakhapatnam, India
| | - Gantyada Lavanya
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Visakhapatnam, India
| | - Ravada Reshmi
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Visakhapatnam, India
| | - Kapil Dev
- Department of Biotechnology, Jamia Millia Islamia, New Delhi, India
| | - Rahul Kumar
- Department of Biotechnology, GITAM Institute of Sciences, GITAM (Deemed to be) University, Visakhapatnam, India
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9
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Kumar R, Tiwari V, Dey S. Role of proline-rich tyrosine kinase 2 (Pyk2) in the pathogenesis of Alzheimer's disease. Eur J Neurosci 2022; 56:5442-5452. [PMID: 34905657 DOI: 10.1111/ejn.15569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD), a progressive neurodegenerative disorder, is the most common form of dementia in the elderly. Two major pathological hallmarks have been identified for AD: extracellular amyloid plaques and intracellular neurofibrillary tangles (NFT). Recently, proline-rich tyrosine kinase 2 (Pyk2), which belongs to the focal adhesion kinase (FAK) non-receptor tyrosine kinase family, was recognized to contribute significantly towards the pathogenesis of AD. Pyk2 can influence the formation of amyloid plaques as well as NFTs. The kinase can directly phosphorylate tau, which is a significant component of NFTs and enhances tau pathology. Several competitive inhibitors have been developed for Pyk2, tested in several cancer models, as Pyk2 is known to be overexpressed under those conditions. The current review article discusses the possible mechanistic pathways by which Pyk2 can influence the pathogenesis of AD. Besides, it describes various inhibitors for Pyk2 and their potential role as therapeutics for AD in the future.
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Affiliation(s)
- Rahul Kumar
- Department of Biotechnology, GITAM Institute of Sciences, GITAM University, Visakhapatnam, India
| | - Vishvanath Tiwari
- Department of Biochemistry, Central University of Rajasthan, Ajmer, India
| | - Sharmistha Dey
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
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10
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Francesca F, Caitlin A, Sarah L, Robyn GL. Antroquinonol administration in animal preclinical studies for Alzheimer's disease (AD): A new avenue for modifying progression of AD pathophysiology. Brain Behav Immun Health 2022; 21:100435. [PMID: 35252893 PMCID: PMC8892093 DOI: 10.1016/j.bbih.2022.100435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/28/2022] [Accepted: 02/22/2022] [Indexed: 11/28/2022] Open
Abstract
Despite the rise of Alzheimer's disease (AD) in an ageing population, no cure is currently available for this disorder. This study assessed the role of a natural compound, Antroquinonol, in modifying the progression of AD when administered at the start and/or before appearance of symptoms and when the disease was well established, in a transgenic animal model. Antroquinonol was administered daily for 8 weeks, in 11 week (early stage) and 9 month (late stage) male transgenic mice (3 times Transgenic mice PS1M146V, APPSwe, and tauP301L, 3 Tg XAD) and their respective aged controls. Behavioural testing (including Elevated Plus Maze Watermaze, Recognition object testing and Y maze) was performed at the end of the drug administration. In addition AD biomarkers (Amyloid beta 42 (Aβ42), tau and phospho-tau levels), oxidative stress and inflammatory markers, were assessed in tested mice brains after their sacrifice at the end of the treatment. When administered before the start of symptoms at 11 weeks, Antroquinonol treatment at 34 mg/kg (D2) and more consistently at 75 mg/kg (D3), had a significant effect on reducing systemic inflammatory markers (Interleukin 1, IL-1β and TNF-α) and AD biomarker (Amyloid Beta 42, Aβ42 and tau) levels in the brain. The reduction of behavioural impairment reported for 3TgXAD mice was observed significantly for the D3 drug dose only and for all behavioural tests, when administered at 11 weeks. Similarly, beneficial effects of Antroquinonol (at higher dose D3) were noted in the transgenic mice in terms of AD biomarkers (tau and phosphorylated-tau), systemic inflammatory (IL-1β), brain anti-inflammatory (Nrf2) and oxidative (3-Nitrotyrosine, 3NT) markers. Improvement of memory impairment was also reported when Antroquinonol (D3) was administered at late stage (9 months). Since Antroquinonol has been used without adverse effects in previous successful clinical trials, this drug may offer a new avenue of treatment to modify AD development and progression.
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Affiliation(s)
- Fernandez Francesca
- School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, 1100 Nudgee Rd, Banyo, Queensland, 4014, Australia
- Centre for Genomics and Personalised Medicine, Genomics Research Centre, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, QLD, 4059, Australia
| | - Aust Caitlin
- School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, 1100 Nudgee Rd, Banyo, Queensland, 4014, Australia
- Centre for Genomics and Personalised Medicine, Genomics Research Centre, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, QLD, 4059, Australia
| | - Lye Sarah
- School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, 1100 Nudgee Rd, Banyo, Queensland, 4014, Australia
- Centre for Genomics and Personalised Medicine, Genomics Research Centre, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, QLD, 4059, Australia
| | - Griffiths Lyn Robyn
- Centre for Genomics and Personalised Medicine, Genomics Research Centre, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove, QLD, 4059, Australia
- Corresponding author. Centre for Genomics and Personalised Health Genomics Research Centre, Queensland University of Technology, Australia.
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11
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Toyos-Rodríguez C, Llamedo-González A, Pando D, García S, García J, García-Alonso F, de la Escosura-Muñiz A. Novel magnetic beads with improved performance for Alzheimer’s disease biomarker detection. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Guan X, Iyaswamy A, Sreenivasmurthy SG, Su C, Zhu Z, Liu J, Kan Y, Cheung KH, Lu J, Tan J, Li M. Mechanistic Insights into Selective Autophagy Subtypes in Alzheimer's Disease. Int J Mol Sci 2022; 23:ijms23073609. [PMID: 35408965 PMCID: PMC8998506 DOI: 10.3390/ijms23073609] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 02/01/2023] Open
Abstract
Eukaryotic cells possess a plethora of regulatory mechanisms to maintain homeostasis and ensure proper biochemical functionality. Autophagy, a central, conserved self-consuming process of the cell, ensures the timely degradation of damaged cellular components. Several studies have demonstrated the important roles of autophagy activation in mitigating neurodegenerative diseases, especially Alzheimer's disease (AD). However, surprisingly, activation of macroautophagy has not shown clinical efficacy. Hence, alternative strategies are urgently needed for AD therapy. In recent years, selective autophagy has been reported to be involved in AD pathology, and different subtypes have been identified, such as aggrephagy, mitophagy, reticulophagy, lipophagy, pexophagy, nucleophagy, lysophagy and ribophagy. By clarifying the underlying mechanisms governing these various subtypes, we may come to understand how to control autophagy to treat AD. In this review, we summarize the latest findings concerning the role of selective autophagy in the pathogenesis of AD. The evidence overwhelmingly suggests that selective autophagy is an active mechanism in AD pathology, and that regulating selective autophagy would be an effective strategy for controlling this pathogenesis.
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Affiliation(s)
- Xinjie Guan
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Ashok Iyaswamy
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Sravan Gopalkrishnashetty Sreenivasmurthy
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Chengfu Su
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Zhou Zhu
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Jia Liu
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Yuxuan Kan
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
| | - King-Ho Cheung
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
| | - Jiahong Lu
- State Key Lab of Quality Research in Chinese Medicine, University of Macau, Macao, China;
| | - Jieqiong Tan
- Center for Medical Genetics, School of Life Sciences, Central South University, Changsha 410000, China
- Correspondence: (J.T.); (M.L.)
| | - Min Li
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China; (X.G.); (A.I.); (S.G.S.); (C.S.); (Z.Z.); (J.L.); (Y.K.); (K.-H.C.)
- Institute for Research and Continuing Education, Hong Kong Baptist University, Shenzhen 518057, China
- Correspondence: (J.T.); (M.L.)
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Trease AJ, George JW, Roland NJ, Lichter EZ, Emanuel K, Totusek S, Fox HS, Stauch KL. Hyperphosphorylated Human Tau Accumulates at the Synapse, Localizing on Synaptic Mitochondrial Outer Membranes and Disrupting Respiration in a Mouse Model of Tauopathy. Front Mol Neurosci 2022; 15:852368. [PMID: 35359570 PMCID: PMC8960727 DOI: 10.3389/fnmol.2022.852368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 01/31/2022] [Indexed: 12/24/2022] Open
Abstract
Neurogenerative disorders, such as Alzheimer’s disease (AD), represent a growing public health challenge in aging societies. Tauopathies, a subset of neurodegenerative disorders that includes AD, are characterized by accumulation of fibrillar and hyperphosphorylated forms of microtubule-associated protein tau with coincident mitochondrial abnormalities and neuronal dysfunction. Although, in vitro, tau impairs axonal transport altering mitochondrial distribution, clear in vivo mechanisms associating tau and mitochondrial dysfunction remain obscure. Herein, we investigated the effects of human tau on brain mitochondria in vivo using transgenic htau mice at ages preceding and coinciding with onset of tauopathy. Subcellular proteomics combined with bioenergetic assessment revealed pathologic forms of tau preferentially associate with synaptic over non-synaptic mitochondria coinciding with changes in bioenergetics, reminiscent of an aged synaptic mitochondrial phenotype in wild-type mice. While mitochondrial content was unaltered, mitochondrial maximal respiration was impaired in synaptosomes from htau mice. Further, mitochondria-associated tau was determined to be outer membrane-associated using the trypsin protection assay and carbonate extraction. These findings reveal non-mutant human tau accumulation at the synapse has deleterious effects on mitochondria, which likely contributes to synaptic dysfunction observed in the context of tauopathy.
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Patthy Á, Murai J, Hanics J, Pintér A, Zahola P, Hökfelt TGM, Harkany T, Alpár A. Neuropathology of the Brainstem to Mechanistically Understand and to Treat Alzheimer's Disease. J Clin Med 2021; 10:jcm10081555. [PMID: 33917176 PMCID: PMC8067882 DOI: 10.3390/jcm10081555] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/01/2021] [Accepted: 04/05/2021] [Indexed: 12/18/2022] Open
Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder as yet without effective therapy. Symptoms of this disorder typically reflect cortical malfunction with local neurohistopathology, which biased investigators to search for focal triggers and molecular mechanisms. Cortex, however, receives massive afferents from caudal brain structures, which do not only convey specific information but powerfully tune ensemble activity. Moreover, there is evidence that the start of AD is subcortical. The brainstem harbors monoamine systems, which establish a dense innervation in both allo- and neocortex. Monoaminergic synapses can co-release neuropeptides either by precisely terminating on cortical neurons or, when being “en passant”, can instigate local volume transmission. Especially due to its early damage, malfunction of the ascending monoaminergic system emerges as an early sign and possible trigger of AD. This review summarizes the involvement and cascaded impairment of brainstem monoaminergic neurons in AD and discusses cellular mechanisms that lead to their dysfunction. We highlight the significance and therapeutic challenges of transmitter co-release in ascending activating system, describe the role and changes of local connections and distant afferents of brainstem nuclei in AD, and summon the rapidly increasing diagnostic window during the last few years.
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Affiliation(s)
- Ágoston Patthy
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary; (Á.P.); (J.M.); (J.H.); (A.P.); (P.Z.)
| | - János Murai
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary; (Á.P.); (J.M.); (J.H.); (A.P.); (P.Z.)
| | - János Hanics
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary; (Á.P.); (J.M.); (J.H.); (A.P.); (P.Z.)
- SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Hungarian Academy of Sciences, H-1094 Budapest, Hungary
| | - Anna Pintér
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary; (Á.P.); (J.M.); (J.H.); (A.P.); (P.Z.)
| | - Péter Zahola
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary; (Á.P.); (J.M.); (J.H.); (A.P.); (P.Z.)
| | - Tomas G. M. Hökfelt
- Department of Neuroscience, Biomedicum 7D, Karolinska Institutet, 17165 Stockholm, Sweden; (T.G.M.H.); (T.H.)
| | - Tibor Harkany
- Department of Neuroscience, Biomedicum 7D, Karolinska Institutet, 17165 Stockholm, Sweden; (T.G.M.H.); (T.H.)
- Center for Brain Research, Department of Molecular Neurosciences, Medical University of Vienna, 1090 Vienna, Austria
| | - Alán Alpár
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary; (Á.P.); (J.M.); (J.H.); (A.P.); (P.Z.)
- SE NAP Research Group of Experimental Neuroanatomy and Developmental Biology, Hungarian Academy of Sciences, H-1094 Budapest, Hungary
- Correspondence:
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15
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Cente M, Zorad S, Smolek T, Fialova L, Paulenka Ivanovova N, Krskova K, Balazova L, Skrabana R, Filipcik P. Plasma Leptin Reflects Progression of Neurofibrillary Pathology in Animal Model of Tauopathy. Cell Mol Neurobiol 2020; 42:125-136. [PMID: 32997211 DOI: 10.1007/s10571-020-00972-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/23/2020] [Indexed: 10/23/2022]
Abstract
The close relationship between Alzheimer's disease (AD) and obesity was recognized many years ago. However, complete understanding of the pathological mechanisms underlying the interactions between degeneration of CNS and fat metabolism is still missing. The leptin a key adipokine of white adipose tissue has been suggested as one of the major mediators linking the obesity and AD. Here we investigated the association between peripheral levels of leptin, general metabolic status and stage of the pathogenesis in rat transgenic model of AD. We demonstrate significantly decreased levels of plasma leptin in animals with experimentally induced progressive neurofibrillary pathology, which represents only 62.3% (P = 0.0015) of those observed in normal wild type control animals. More detailed analysis showed a strong and statistically significant inverse correlation between the load of neurofibrillary pathology and peripheral levels of leptin (r = - 0.7248, P = 0.0177). We also observed a loss of body weight during development of neurodegeneration (about 14% less than control animals, P = 0.0004) and decrease in several metabolic parameters such as glucose, insulin, triglycerides and VLDL in plasma of the transgenic animals. Our data suggest that plasma leptin could serve as a convenient peripheral biomarker for tauopathies and Alzheimer's disease. Decrease in gene expression of leptin in fat tissue and its plasma level was found as one of the consequences of experimentally induced neurodegeneration. Our data may help to design rational diagnostic and therapeutic strategies for patients suffering from Alzheimer's disease or other forms of tauopathy.
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Affiliation(s)
- Martin Cente
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10, Bratislava, Slovakia.,Axon Neuroscience R&D Services SE, Bratislava, Slovakia
| | - Stefan Zorad
- Institute of Experimental Endocrinology, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Tomas Smolek
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10, Bratislava, Slovakia.,Axon Neuroscience R&D Services SE, Bratislava, Slovakia
| | - Lubica Fialova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10, Bratislava, Slovakia.,Axon Neuroscience R&D Services SE, Bratislava, Slovakia
| | | | - Katarina Krskova
- Institute of Experimental Endocrinology, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Lucia Balazova
- Institute of Experimental Endocrinology, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Rostislav Skrabana
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10, Bratislava, Slovakia.,Axon Neuroscience R&D Services SE, Bratislava, Slovakia
| | - Peter Filipcik
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10, Bratislava, Slovakia. .,Axon Neuroscience R&D Services SE, Bratislava, Slovakia.
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16
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Liu XY, Yang LP, Zhao L. Stem cell therapy for Alzheimer's disease. World J Stem Cells 2020; 12:787-802. [PMID: 32952859 PMCID: PMC7477654 DOI: 10.4252/wjsc.v12.i8.787] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/10/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory loss and cognitive impairment. It is caused by synaptic failure and excessive accumulation of misfolded proteins. To date, almost all advanced clinical trials on specific AD-related pathways have failed mostly due to a large number of neurons lost in the brain of patients with AD. Also, currently available drug candidates intervene too late. Stem cells have improved characteristics of self-renewal, proliferation, differentiation, and recombination with the advent of stem cell technology and the transformation of these cells into different types of central nervous system neurons and glial cells. Stem cell treatment has been successful in AD animal models. Recent preclinical studies on stem cell therapy for AD have proved to be promising. Cell replacement therapies, such as human embryonic stem cells or induced pluripotent stem cell–derived neural cells, have the potential to treat patients with AD, and human clinical trials are ongoing in this regard. However, many steps still need to be taken before stem cell therapy becomes a clinically feasible treatment for human AD and related diseases. This paper reviews the pathophysiology of AD and the application prospects of related stem cells based on cell type.
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Affiliation(s)
- Xin-Yu Liu
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
| | - Lin-Po Yang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
| | - Lan Zhao
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
- Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin 300381, China
- National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin 300381, China
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17
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Toyos-Rodríguez C, García-Alonso FJ, de la Escosura-Muñiz A. Electrochemical Biosensors Based on Nanomaterials for Early Detection of Alzheimer's Disease. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4748. [PMID: 32842632 PMCID: PMC7506792 DOI: 10.3390/s20174748] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is an untreatable neurodegenerative disease that initially manifests as difficulty to remember recent events and gradually progresses to cognitive impairment. The incidence of AD is growing yearly as life expectancy increases, thus early detection is essential to ensure a better quality of life for diagnosed patients. To reach that purpose, electrochemical biosensing has emerged as a cost-effective alternative to traditional diagnostic techniques, due to its high sensitivity and selectivity. Of special relevance is the incorporation of nanomaterials in biosensors, as they contribute to enhance electron transfer while promoting the immobilization of biological recognition elements. Moreover, nanomaterials have also been employed as labels, due to their unique electroactive and electrocatalytic properties. The aim of this review is to add value in the advances achieved in the detection of AD biomarkers, the strategies followed for the incorporation of nanomaterials and its effect in biosensors performance.
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Affiliation(s)
- Celia Toyos-Rodríguez
- NanoBioAnalysis Group-Department of Physical and Analytical Chemistry, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain;
- Biotechnology Institute of Asturias, University of Oviedo, Santiago Gascon Building, 33006 Oviedo, Spain;
| | - Francisco Javier García-Alonso
- Biotechnology Institute of Asturias, University of Oviedo, Santiago Gascon Building, 33006 Oviedo, Spain;
- NanoBioAnalysis Group-Department of Organic and Inorganic Chemistry, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain
| | - Alfredo de la Escosura-Muñiz
- NanoBioAnalysis Group-Department of Physical and Analytical Chemistry, University of Oviedo, Julián Clavería 8, 33006 Oviedo, Spain;
- Biotechnology Institute of Asturias, University of Oviedo, Santiago Gascon Building, 33006 Oviedo, Spain;
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18
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Zhang FQ, Jiang JL, Zhang JT, Niu H, Fu XQ, Zeng LL. Current status and future prospects of stem cell therapy in Alzheimer's disease. Neural Regen Res 2020; 15:242-250. [PMID: 31552889 PMCID: PMC6905342 DOI: 10.4103/1673-5374.265544] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 03/18/2019] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease is a common progressive neurodegenerative disorder, pathologically characterized by the presence of β-amyloid plaques and neurofibrillary tangles. Current treatment approaches using drugs only alleviate the symptoms without curing the disease, which is a serious issue and influences the quality of life of the patients and their caregivers. In recent years, stem cell technology has provided new insights into the treatment of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Currently, the main sources of stem cells include neural stem cells, embryonic stem cells, mesenchymal stem cells, and induced pluripotent stem cells. In this review, we discuss the pathophysiology and general treatment of Alzheimer's disease, and the current state of stem cell transplantation in the treatment of Alzheimer's disease. We also assess future challenges in the clinical application and drug development of stem cell transplantation as a treatment for Alzheimer's disease.
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Affiliation(s)
- Fu-Qiang Zhang
- Scientific Research Centre of China-Japan Union Hospital, Jilin University, Changchun, Jilin Province, China
| | - Jin-Lan Jiang
- Scientific Research Centre of China-Japan Union Hospital, Jilin University, Changchun, Jilin Province, China
| | - Jing-Tian Zhang
- School of Life Sciences, Jilin University, Changchun, Jilin Province, China
| | - Han Niu
- School of Life Sciences, Jilin University, Changchun, Jilin Province, China
| | - Xue-Qi Fu
- School of Life Sciences, Jilin University, Changchun, Jilin Province, China
| | - Lin-Lin Zeng
- School of Life Sciences, Jilin University, Changchun, Jilin Province, China
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19
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Targeting Aggrephagy for the Treatment of Alzheimer's Disease. Cells 2020; 9:cells9020311. [PMID: 32012902 PMCID: PMC7072705 DOI: 10.3390/cells9020311] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 01/25/2020] [Accepted: 01/26/2020] [Indexed: 12/17/2022] Open
Abstract
Alzheimer’s disease (AD) is one of the most common neurodegenerative diseases in older individuals with specific neuropsychiatric symptoms. It is a proteinopathy, pathologically characterized by the presence of misfolded protein (Aβ and Tau) aggregates in the brain, causing progressive dementia. Increasing studies have provided evidence that the defect in protein-degrading systems, especially the autophagy-lysosome pathway (ALP), plays an important role in the pathogenesis of AD. Recent studies have demonstrated that AD-associated protein aggregates can be selectively recognized by some receptors and then be degraded by ALP, a process termed aggrephagy. In this study, we reviewed the role of aggrephagy in AD development and discussed the strategy of promoting aggrephagy using small molecules for the treatment of AD.
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20
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Nakhate KT, Bharne AP, Verma VS, Aru DN, Kokare DM. Plumbagin ameliorates memory dysfunction in streptozotocin induced Alzheimer’s disease via activation of Nrf2/ARE pathway and inhibition of β-secretase. Biomed Pharmacother 2018; 101:379-390. [DOI: 10.1016/j.biopha.2018.02.052] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/31/2018] [Accepted: 02/13/2018] [Indexed: 01/01/2023] Open
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21
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Castillo-Ordóñez WO, Tamarozzi ER, da Silva GM, Aristizabal-Pachón AF, Sakamoto-Hojo ET, Takahashi CS, Giuliatti S. Exploration of the Acetylcholinesterase Inhibitory Activity of Some Alkaloids from Amaryllidaceae Family by Molecular Docking In Silico. Neurochem Res 2017; 42:2826-2830. [DOI: 10.1007/s11064-017-2295-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 04/27/2017] [Accepted: 05/06/2017] [Indexed: 01/24/2023]
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22
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Varnum MM, Clayton KA, Yoshii-Kitahara A, Yonemoto G, Koro L, Ikezu S, Ikezu T. A split-luciferase complementation, real-time reporting assay enables monitoring of the disease-associated transmembrane protein TREM2 in live cells. J Biol Chem 2017; 292:10651-10663. [PMID: 28490631 DOI: 10.1074/jbc.m116.759159] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 04/20/2017] [Indexed: 12/18/2022] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a single transmembrane molecule uniquely expressed in microglia. TREM2 mutations are genetically linked to Nasu-Hakola disease and associated with multiple neurodegenerative disorders, including Alzheimer's disease. TREM2 may regulate microglial inflammation and phagocytosis through coupling to the adaptor protein TYRO protein-tyrosine kinase-binding protein (TYROBP). However, there is no functional system for monitoring this protein-protein interaction. We developed a luciferase-based modality for real-time monitoring of TREM2-TYROBP coupling in live cells that utilizes split-luciferase complementation technology based on TREM2 and TYROBP fusion to the C- or N-terminal portion of the Renilla luciferase gene. Transient transfection of human embryonic kidney 293 cells with this reporter vector increased luciferase activity upon stimulation with an anti-TREM2 antibody, which induces their homodimerization. This was confirmed by ELISA-based analysis of the TREM2-TYROBP interaction. Antibody-mediated TREM2 stimulation enhanced spleen tyrosine kinase (SYK) activity and uptake of Staphylococcus aureus in microglial cell line BV-2 in a kinase-dependent manner. Interestingly, the TREM2 T66M mutation significantly enhanced luciferase activity without stimulation, indicating constitutive coupling to TYROBP. Finally, flow cytometry analyses indicated significantly lower surface expression of T66M TREM2 variant than wild type or other TREM2 variants. These results demonstrate that our TREM2 reporter vector is a novel tool for monitoring the TREM2-TYROBP interaction in real time.
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Affiliation(s)
- Megan M Varnum
- From the Departments of Pharmacology and Experimental Therapeutics and
| | - Kevin A Clayton
- From the Departments of Pharmacology and Experimental Therapeutics and
| | | | - Grant Yonemoto
- From the Departments of Pharmacology and Experimental Therapeutics and
| | - Lacin Koro
- From the Departments of Pharmacology and Experimental Therapeutics and
| | - Seiko Ikezu
- From the Departments of Pharmacology and Experimental Therapeutics and
| | - Tsuneya Ikezu
- From the Departments of Pharmacology and Experimental Therapeutics and .,Neurology, Boston University School of Medicine, Boston, Massachusetts 02118
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23
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Agadjanyan MG, Zagorski K, Petrushina I, Davtyan H, Kazarian K, Antonenko M, Davis J, Bon C, Blurton-Jones M, Cribbs DH, Ghochikyan A. Humanized monoclonal antibody armanezumab specific to N-terminus of pathological tau: characterization and therapeutic potency. Mol Neurodegener 2017; 12:33. [PMID: 28472993 PMCID: PMC5418694 DOI: 10.1186/s13024-017-0172-1] [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: 09/29/2016] [Accepted: 04/07/2017] [Indexed: 01/01/2023] Open
Abstract
Background The experience from clinical trials indicates that anti-Aβ immunotherapy could be effective in early/pre-clinical stages of AD, whereas at the late stages promoting the clearing of Aβ alone may be insufficient to halt the disease progression. At the same time, pathological tau correlates much better with the degree of dementia than Aβ deposition. Therefore, targeting pathological tau may provide a more promising approach for the treatment of advanced stages of AD. Recent data demonstrates that the N-terminal region of tau spanning aa 2–18 termed “phosphatase activation domain” that is normally hidden in the native protein in ‘paperclip’-like conformation, becomes exposed in pathological tau and plays an essential role in the inhibition of fast axonal transport and in aggregation of tau. Hence, we hypothesized that anti-Tau2–18 monoclonal antibodies (mAb) may recognize pathological, but not normal tau at very early stages of tauopathy and prevent or decrease the aggregation of this molecule. Methods Mouse mAbs were generated using standard hybridoma methodology. CDR grafting was used for humanization of mouse mAb. Humanized mAb (Armanezumab) was characterized and tested in vitro/ex vivo/in vivo using biochemical and immunological methods (HPLC, Biacore, ELISA, IHC, FRET, etc.). Stable DG44 cell line expressing Armanezumab was generated by clone selection with increased concentrations of methotrexate (MTX). Results A panel of mouse mAbs was generated, clone 1C9 was selected based on binding to pathological human tau with high affinity and humanized. Fine epitope mapping revealed conservation of the epitope of human tau recognized by the parent murine mAb and Armanezumab. Importantly, Armanezumab (i) bound to tau with high affinity as determined by Biacore; (ii) bound pathological tau in brains from AD, FTD and Pick’s disease cases; (iii) inhibited seeding effect of aggregated tau from brain lysate of P301S Tg mice; (iv) inhibited cytotoxic effect of tau oligomers; (v) reduced total tau (HT7) and AT100, PHF1, AT8, AT180, p212, p214-positive tau species in brains of tau transgenic mice after intracranial injection. A stable CHO cell line producing >1.5 g/l humanized mAb, Armanezumab was generated. Conclusion These findings suggest that Armanezumab could be therapeutic in clinical studies for treatment of AD.
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Affiliation(s)
- Michael G Agadjanyan
- Department of Molecular Immunology, Institute for Molecular Medicine, 16371 Gothard St, Huntington Beach, CA, 92647, USA. .,The Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, 92697, USA.
| | - Karen Zagorski
- Department of Molecular Immunology, Institute for Molecular Medicine, 16371 Gothard St, Huntington Beach, CA, 92647, USA.,Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE, 68198-6025, USA
| | - Irina Petrushina
- The Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, 92697, USA
| | - Hayk Davtyan
- Department of Molecular Immunology, Institute for Molecular Medicine, 16371 Gothard St, Huntington Beach, CA, 92647, USA
| | - Konstantin Kazarian
- Department of Molecular Immunology, Institute for Molecular Medicine, 16371 Gothard St, Huntington Beach, CA, 92647, USA
| | - Maxim Antonenko
- Department of Molecular Immunology, Institute for Molecular Medicine, 16371 Gothard St, Huntington Beach, CA, 92647, USA
| | - Joy Davis
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA, 92697, USA
| | | | - Mathew Blurton-Jones
- The Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, 92697, USA.,Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA, 92697, USA
| | - David H Cribbs
- The Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, 92697, USA
| | - Anahit Ghochikyan
- Department of Molecular Immunology, Institute for Molecular Medicine, 16371 Gothard St, Huntington Beach, CA, 92647, USA.
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The role of neuropathological markers in the interpretation of neuropsychiatric disorders: Focus on fetal and perinatal programming. Neurosci Lett 2016; 669:75-82. [PMID: 27818357 DOI: 10.1016/j.neulet.2016.10.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 10/24/2016] [Accepted: 10/25/2016] [Indexed: 12/29/2022]
Abstract
The study of neuropathological markers in patients affected by mental/psychiatric disorders is relevant for the comprehension of the pathogenesis and the correlation with the clinical symptomatology. The neuropathology of Alzheimer's disease (AD) recognizes intraneuronal and extracellular neurofibrillary formation responsible for neuronal degeneration. Immunohistochemical studies discovered many interesting results for a better interpretation of the AD pathogenesis, while the "metal hypothesis" supports that metal ions might differentially influence the formation of amyloid aggregates. The most relevant pathological findings reported in schizophrenia originate from computer assisted tomography (CT), Magnetic Resonance Imaging (MRI) studies and Diffusion Tensor Imaging (DTI), suggesting the brain abnormalities involved in the pathophysiology of schizophrenia. The theory of fetal programming illustrates the epigenetic factors that may act during the intrauterine life on brain development, with relevant consequences on the susceptibility to develop AD or schizophrenia later in life. The neuropathological interpretation of AD and schizophrenia shows that the presence of severe neuropathological changes is not always associated with severe cognitive impairment. A better dialogue between psychiatrics and pathologists might help to halt insurgence and progression of neurodegenerative diseases.
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Majd S, Power JHT, Koblar SA, Grantham HJM. Early glycogen synthase kinase-3β and protein phosphatase 2A independent tau dephosphorylation during global brain ischaemia and reperfusion following cardiac arrest and the role of the adenosine monophosphate kinase pathway. Eur J Neurosci 2016; 44:1987-97. [PMID: 27177932 PMCID: PMC5089632 DOI: 10.1111/ejn.13277] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 04/27/2016] [Accepted: 04/28/2016] [Indexed: 12/13/2022]
Abstract
Abnormal tau phosphorylation (p‐tau) has been shown after hypoxic damage to the brain associated with traumatic brain injury and stroke. As the level of p‐tau is controlled by Glycogen Synthase Kinase (GSK)‐3β, Protein Phosphatase 2A (PP2A) and Adenosine Monophosphate Kinase (AMPK), different activity levels of these enzymes could be involved in tau phosphorylation following ischaemia. This study assessed the effects of global brain ischaemia/reperfusion on the immediate status of p‐tau in a rat model of cardiac arrest (CA) followed by cardiopulmonary resuscitation (CPR). We reported an early dephosphorylation of tau at its AMPK sensitive residues, Ser396 and Ser262after 2 min of ischaemia, which did not recover during the first two hours of reperfusion, while the tau phosphorylation at GSK‐3β sensitive but AMPK insensitive residues, Ser202/Thr205 (AT8), as well as the total amount of tau remained unchanged. Our data showed no alteration in the activities of GSK‐3β and PP2A during similar episodes of ischaemia of up to 8 min and reperfusion of up to 2 h, and 4 weeks recovery. Dephosphorylation of AMPK followed the same pattern as tau dephosphorylation during ischaemia/reperfusion. Catalase, another AMPK downstream substrate also showed a similar pattern of decline to p‐AMPK, in ischaemic/reperfusion groups. This suggests the involvement of AMPK in changing the p‐tau levels, indicating that tau dephosphorylation following ischaemia is not dependent on GSK‐3β or PP2A activity, but is associated with AMPK dephosphorylation. We propose that a reduction in AMPK activity is a possible early mechanism responsible for tau dephosphorylation.
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Affiliation(s)
- Shohreh Majd
- Centre for Neuroscience, Neuronal Injury and Repair Laboratory, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia
| | - John H T Power
- Department of Human Physiology, School of Medicine, Flinders University of South Australia, Adelaide, SA, Australia
| | - Simon A Koblar
- School of Medicine, The Queen Elizabeth Hospital (TQEH) Campus, University of Adelaide, Adelaide, SA, Australia
| | - Hugh J M Grantham
- Centre for Neuroscience, Neuronal Injury and Repair Laboratory, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia
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Maj M, Hoermann G, Rasul S, Base W, Wagner L, Attems J. The Microtubule-Associated Protein Tau and Its Relevance for Pancreatic Beta Cells. J Diabetes Res 2016; 2016:1964634. [PMID: 26824039 PMCID: PMC4707345 DOI: 10.1155/2016/1964634] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 11/24/2015] [Indexed: 12/02/2022] Open
Abstract
Structural and biochemical alterations of the microtubule-associated protein tau (MAPT) are associated with degenerative disorders referred to as tauopathies. We have previously shown that MAPT is present in human islets of Langerhans, human insulinomas, and pancreatic beta-cell line models, with biophysical similarities to the pathological MAPT in the brain. Here, we further studied MAPT in pancreatic endocrine tissue to better understand the mechanisms that lead to functional dysregulation of pancreatic beta cells. We found upregulation of MAPT protein expression in human insulinomas when compared to human pancreatic islets of Langerhans and an imbalance between MAPT isoforms in insulinomas tissue. We cloned one 3-repeat domain MAPT and transduced this into a beta-cell derived rodent cell line Rin-5F. Proliferation experiments showed higher growth rates and metabolic activities of cells overexpressing MAPT protein. We observed that a MAPT overexpressing cell line demonstrates altered insulin transcription, translation, and insulin secretion rates. We found the relative insulin secretion rates were significantly decreased in a MAPT overexpressing cell line and these findings could be confirmed using partial MAPT knock-down cell lines. Our findings support that MAPT may play an important role in insulin granule trafficking and indicate the importance of balanced MAPT phosphorylation and dephosphorylation for adequate insulin release.
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Affiliation(s)
- Magdalena Maj
- Department of Internal Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, 1090 Vienna, Austria
- *Magdalena Maj:
| | - Gregor Hoermann
- Department of Laboratory Medicine, Medical University of Vienna, 1090 Vienna, Austria
| | - Sazan Rasul
- Department of Internal Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, 1090 Vienna, Austria
| | - Wolfgang Base
- Department of Internal Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, 1090 Vienna, Austria
| | - Ludwig Wagner
- Department of Internal Medicine III, Division of Nephrology and Dialysis, Medical University of Vienna, 1090 Vienna, Austria
| | - Johannes Attems
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
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Majd S, Power JH, Grantham HJM. Neuronal response in Alzheimer's and Parkinson's disease: the effect of toxic proteins on intracellular pathways. BMC Neurosci 2015; 16:69. [PMID: 26499115 PMCID: PMC4619058 DOI: 10.1186/s12868-015-0211-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 10/13/2015] [Indexed: 01/09/2023] Open
Abstract
Accumulation of protein aggregates is the leading cause of cellular dysfunction in neurodegenerative disorders. Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease, Prion disease and motor disorders such as amyotrophic lateral sclerosis, present with a similar pattern of progressive neuronal death, nervous system deterioration and cognitive impairment. The common characteristic is an unusual misfolding of proteins which is believed to cause protein deposition and trigger degenerative signals in the neurons. A similar clinical presentation seen in many neurodegenerative disorders suggests the possibility of shared neuronal responses in different disorders. Despite the difference in core elements of deposits in each neurodegenerative disorder, the cascade of neuronal reactions such as activation of glycogen synthase kinase-3 beta, mitogen-activated protein kinases, cell cycle re-entry and oxidative stress leading to a progressive neurodegeneration are surprisingly similar. This review focuses on protein toxicity in two neurodegenerative diseases, AD and PD. We reviewed the activated mechanisms of neurotoxicity in response to misfolded beta-amyloid and α-synuclein, two major toxic proteins in AD and PD, leading to neuronal apoptosis. The interaction between the proteins in producing an overlapping pathological pattern will be also discussed.
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Affiliation(s)
- Shohreh Majd
- Centre for Neuroscience and Paramedic Unit, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia.
| | - John H Power
- Department of Human Physiology, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia.
| | - Hugh J M Grantham
- Centre for Neuroscience and Paramedic Unit, School of Medicine, Flinders University of South Australia, Adelaide, SA, 5042, Australia.
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Subthreshold Concentrations of Melatonin and Galantamine Improves Pathological AD-Hallmarks in Hippocampal Organotypic Cultures. Mol Neurobiol 2015; 53:3338-3348. [PMID: 26081146 DOI: 10.1007/s12035-015-9272-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 05/28/2015] [Indexed: 12/16/2022]
Abstract
Melatonin is a neurohormone whose levels are significantly reduced or absent in Alzheimer's disease (AD) patients. In these patients, acetylcholinesterase inhibitors (AChEI) are the major drug class used for their treatment; however, they present unwanted cholinergic side effects and have provided limited efficacy in clinic. Because combination therapy is being extensively used to treat different pathological diseases such as cancer or acquired immune deficiency syndrome, we posed this study to evaluate if melatonin in combination with an AChEI, galantamine, could provide beneficial properties in a novel in vitro model of AD. Thus, we subjected organotypic hippocampal cultures (OHCs) to subtoxic concentrations of β-amyloid (0.5 μM βA) plus okadaic acid (1 nM OA), for 4 days. This treatment increased by 95 % cell death, which was mainly apoptotic as shown by positive TUNEL staining. In addition, the combination of βA/OA increased Thioflavin S aggregates, hyperphosphorylation of Tau, oxidative stress (increased DCFDA fluorescence), and neuroinflammation (increased IL-1β and TNFα). Under these experimental conditions, melatonin (1-1000 nM) and galantamine (10-1000 nM), co-incubated with the toxic stimuli, caused a concentration-dependent neuroprotection; maximal neuroprotective effect was achieved at 1 μM of melatonin and galantamine. Most effective was the finding that combination of sub-effective concentrations of melatonin (1 nM) and galantamine (10 nM) provided a synergic anti-apoptotic effect and reduction of most of the AD-related pathological hallmarks observed in the βA/OA model. Therefore, we suggest that supplementation of melatonin in combination with lower doses of AChEIs could be an interesting strategy for AD patients.
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Abstract
Alzheimer's disease (AD) is the foremost cause of dementia worldwide. Clinically, AD manifests as progressive memory impairment followed by a gradual decline in other cognitive abilities leading to complete functional dependency. Recent biomarker studies indicate that AD is characterized by a long asymptomatic phase, with the development of pathology occurring at least a decade prior to the onset of any symptoms. Current FDA-approved treatments target neurotransmitter abnormalities associated with the disease but do not affect what is believed to be the underlying etiology. In this review, we briefly discuss the most recent therapeutic strategies being employed in AD clinical trials, as well the scientific rationale with which they have been developed.
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Stem cell treatment for Alzheimer's disease. Int J Mol Sci 2014; 15:19226-38. [PMID: 25342318 PMCID: PMC4227270 DOI: 10.3390/ijms151019226] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 10/09/2014] [Accepted: 10/10/2014] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is a progressive and neurodegenerative disorder that induces dementia in older people. It was first reported in 1907 by Alois Alzheimer, who characterized the disease as causing memory loss and cognitive impairment. Pathologic characteristics of AD are β-amyloid plaques, neurofibrillary tangles and neurodegeneration. Current therapies only target the relief of symptoms using various drugs, and do not cure the disease. Recently, stem cell therapy has been shown to be a potential approach to various diseases, including neurodegenerative disorders, and in this review, we focus on stem cell therapies for AD.
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Complex regulation of acute and chronic neuroinflammatory responses in mouse models deficient for nuclear factor kappa B p50 subunit. Neurobiol Dis 2014; 64:16-29. [DOI: 10.1016/j.nbd.2013.12.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Revised: 11/11/2013] [Accepted: 12/04/2013] [Indexed: 12/29/2022] Open
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Choi SS, Lee SR, Kim SU, Lee HJ. Alzheimer's disease and stem cell therapy. Exp Neurobiol 2014; 23:45-52. [PMID: 24737939 PMCID: PMC3984956 DOI: 10.5607/en.2014.23.1.45] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 02/28/2014] [Accepted: 02/28/2014] [Indexed: 12/19/2022] Open
Abstract
The loss of neuronal cells in the central nervous system may occur in many neurodegenerative diseases. Alzheimer's disease is a common senile disease in people over 65 years, and it causes impairment characterized by the decline of mental function, including memory loss and cognitive impairment, and affects the quality of life of patients. However, the current therapeutic strategies against AD are only to relieve symptoms, but not to cure it. Because there are only a few therapeutic strategies against Alzheimer's disease, we need to understand the pathogenesis of this disease. Cell therapy may be a powerful tool for the treatment of Alzheimer's disease. This review will discuss the characteristics of Alzheimer's disease and various available therapeutic strategies.
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Affiliation(s)
- Sung S Choi
- Medical Research Institute, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Sang-Rae Lee
- National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology, Ochang 363-883, Korea
| | - Seung U Kim
- Division of Neurology, Department of Medicine, University of British Columbia, Vancouver 317-2194, Canada
| | - Hong J Lee
- Medical Research Institute, Chung-Ang University College of Medicine, Seoul 156-756, Korea
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Vaidyanathan K, Durning S, Wells L. Functional O-GlcNAc modifications: implications in molecular regulation and pathophysiology. Crit Rev Biochem Mol Biol 2014; 49:140-163. [PMID: 24524620 PMCID: PMC4912837 DOI: 10.3109/10409238.2014.884535] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
O-linked β-N-acetylglucosamine (O-GlcNAc) is a regulatory post-translational modification of intracellular proteins. The dynamic and inducible cycling of the modification is governed by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) in response to UDP-GlcNAc levels in the hexosamine biosynthetic pathway (HBP). Due to its reliance on glucose flux and substrate availability, a major focus in the field has been on how O-GlcNAc contributes to metabolic disease. For years this post-translational modification has been known to modify thousands of proteins implicated in various disorders, but direct functional connections have until recently remained elusive. New research is beginning to reveal the specific mechanisms through which O-GlcNAc influences cell dynamics and disease pathology including clear examples of O-GlcNAc modification at a specific site on a given protein altering its biological functions. The following review intends to focus primarily on studies in the last half decade linking O-GlcNAc modification of proteins with chromatin-directed gene regulation, developmental processes, and several metabolically related disorders including Alzheimer's, heart disease and cancer. These studies illustrate the emerging importance of this post-translational modification in biological processes and multiple pathophysiologies.
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Affiliation(s)
| | - Sean Durning
- Complex Carbohydrate Research Center, University of Georgia, Athens, USA
| | - Lance Wells
- Complex Carbohydrate Research Center, University of Georgia, Athens, USA
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Zetzsche T, Rujescu D, Hardy J, Hampel H. Advances and perspectives from genetic research: development of biological markers in Alzheimer’s disease. Expert Rev Mol Diagn 2014; 10:667-90. [PMID: 20629514 DOI: 10.1586/erm.10.48] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Thomas Zetzsche
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilian-University, Nussbaumstrasse 7, Munich, Germany. thomas.zetzsche@ med.uni-muenchen.de
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35
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Lee SL, Thomas P, Fenech M. Extracellular amyloid beta 42 causes necrosis, inhibition of nuclear division, and mitotic disruption under both folate deficient and folate replete conditions as measured by the cytokinesis-block micronucleus cytome assay. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:1-14. [PMID: 24038346 DOI: 10.1002/em.21811] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/17/2013] [Accepted: 07/19/2013] [Indexed: 06/02/2023]
Abstract
Alzheimer's disease is associated with accumulation of extracellular beta amyloid peptide 42 (Aβ42) which may induce DNA damage and reduce cellular regenerative potential. These effects may be exacerbated under conditions of folate deficiency. The aim of this study was to investigate whether extracellular Aβ42 induces DNA damage and cell death in human peripheral lymphocytes and whether there is an interactive effect between extracellular Aβ42 and folic acid status. Peripheral blood lymphocytes were cultured in medium under conditions of both low and high folate (20 and 200 nM, respectively) and challenged with either Aβ42 or the physiologically normal form Aβ40 (both at 5, 10, 15 µM). Genome stability and cytotoxicity events were investigated using the cytokinesis-block micronucleus cytome (CBMN-cyt) assay. Outcome measures scored included the nuclear division index (NDI), necrosis, apoptosis, binucleated cells with micronuclei (MN), nucleoplasmic bridges (NPB), and nuclear buds (NBUD) and abnormally shaped nuclei (circular, (CIR) and horse-shoe, (HS) that may be indicative of mitotic disruption. Folic acid deficiency significantly reduced NDI (P < 0.001) and increased all the DNA damage biomarkers (MN, NPB, NBUD, HS, CIR), (P < 0.001). In contrast, exposure to Aβ40 had no impact on CBMN cytome biomarkers but Aβ42 significantly reduced NDI (P < 0.01), increased necrosis (P < 0.05) and frequency of cells with circular nuclei (P < 0.01). There was no evidence of an interaction between Aβ42 and folic acid with respect to CBMN cytome biomarkers. Extracellular Aβ42 appears to have cytotoxic and cytostatic effects but its effect on chromosomal instability appears to be small relative to folate deficiency.
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Affiliation(s)
- Sau Lai Lee
- Commonwealth Scientific and Industrial Research Organisation, (Animal, Food and Health Sciences), Adelaide, South Australia, 5000; Discipline of Physiology, School of Medical Sciences, The University of Adelaide, Adelaide, South Australia, 5005
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Noble W, Hanger DP, Miller CCJ, Lovestone S. The importance of tau phosphorylation for neurodegenerative diseases. Front Neurol 2013; 4:83. [PMID: 23847585 PMCID: PMC3696910 DOI: 10.3389/fneur.2013.00083] [Citation(s) in RCA: 263] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 06/14/2013] [Indexed: 01/20/2023] Open
Abstract
Fibrillar deposits of highly phosphorylated tau are a key pathological feature of several neurodegenerative tauopathies including Alzheimer's disease (AD) and some frontotemporal dementias. Increasing evidence suggests that the presence of these end-stage neurofibrillary lesions do not cause neuronal loss, but rather that alterations to soluble tau proteins induce neurodegeneration. In particular, aberrant tau phosphorylation is acknowledged to be a key disease process, influencing tau structure, distribution, and function in neurons. Although typically described as a cytosolic protein that associates with microtubules and regulates axonal transport, several additional functions of tau have recently been demonstrated, including roles in DNA stabilization, and synaptic function. Most recently, studies examining the trans-synaptic spread of tau pathology in disease models have suggested a potential role for extracellular tau in cell signaling pathways intrinsic to neurodegeneration. Here we review the evidence showing that tau phosphorylation plays a key role in neurodegenerative tauopathies. We also comment on the tractability of altering phosphorylation-dependent tau functions for therapeutic intervention in AD and related disorders.
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Affiliation(s)
- Wendy Noble
- Department of Neuroscience, King's College London, Institute of Psychiatry , London , UK
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Shuai H, Zhang J, Zhang J, Xie J, Zhang M, Ma J, Zhang L, Wang X. Role of stereotaxically injected IgG from db/db mice in the phosphorylation of the microtubule-associated protein tau in hippocampus. Brain Res 2012; 1486:14-26. [PMID: 23036273 DOI: 10.1016/j.brainres.2012.08.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 08/21/2012] [Accepted: 08/25/2012] [Indexed: 11/29/2022]
Abstract
People with type 2 diabetes (T2DM) mellitus are high risk for dementia and Alzheimer's disease (AD) via several plausible pathways. However, the underlying mechanisms have been still unclear, and the relation of immune injury to the pathogenesis of T2DM-related AD is not yet completely understood. Our present study aimed to elucidate the possible role of immunoglobulin IgG in the immune process of AD associated with T2DM in db/db mice. Hippocampi of 20 db/db mice and 20 C57BL/6 mice were subjected to immunohistochemistry and immunofluorescence assays. The phosphorylation of tau, glycogen synthase kinase (GSK)-3β and AKT activity was examined by Western blot analysis. IgG purified from the sera of IgG deposit-positive db/db mice was stereotaxically injected into the hippocampi of another 12 db/db mice and 12 C57BL/6 mice. The phosphorylation of tau, Abeta, GSK-3β and AKT activity was analyzed. Compared with the C57BL/6 control, 13 of the 20 db/db mice exhibited high levels of IgG deposits in the hippocampus. Treatment with IgG triggered tau hyperphosphorylations and Abeta deposition, which are likely major factors in AD. Meanwhile, IgG inhibited AKT phosphorylation and promoted GSK-3β activity. The IgG deposits observed in some db/db mice were possibly related to the impairment of T2DM-related AD development. Some autoimmune processes may be involved in AD in type 2 diabetes mellitus development at the level of the hippocampus.
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Affiliation(s)
- Hongxia Shuai
- Department of Endocrinology, XiangYang Central Hospital, XiangYang, China
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Maulik M, Westaway D, Jhamandas JH, Kar S. Role of cholesterol in APP metabolism and its significance in Alzheimer's disease pathogenesis. Mol Neurobiol 2012; 47:37-63. [PMID: 22983915 DOI: 10.1007/s12035-012-8337-y] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 08/19/2012] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is a complex multifactorial neurodegenerative disorder believed to be initiated by accumulation of amyloid β (Aβ)-related peptides derived from proteolytic processing of amyloid precursor protein (APP). Research over the past two decades provided a mechanistic link between cholesterol and AD pathogenesis. Genetic polymorphisms in genes regulating the pivotal points in cholesterol metabolism have been suggested to enhance the risk of developing AD. Altered neuronal membrane cholesterol level and/or subcellular distribution have been implicated in aberrant formation, aggregation, toxicity, and degradation of Aβ-related peptides. However, the results are somewhat contradictory and we still do not have a complete understanding on how cholesterol can influence AD pathogenesis. In this review, we summarize our current understanding on the role of cholesterol in regulating the production/function of Aβ-related peptides and also examine the therapeutic potential of regulating cholesterol homeostasis in the treatment of AD pathology.
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Affiliation(s)
- M Maulik
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
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Varnum MM, Ikezu T. The classification of microglial activation phenotypes on neurodegeneration and regeneration in Alzheimer's disease brain. Arch Immunol Ther Exp (Warsz) 2012; 60:251-66. [PMID: 22710659 PMCID: PMC4429536 DOI: 10.1007/s00005-012-0181-2] [Citation(s) in RCA: 284] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 02/20/2012] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive decline of cognitive function. There is no therapy that can halt or reverse its progression. Contemporary research suggests that age-dependent neuroinflammatory changes may play a significant role in the decreased neurogenesis and cognitive impairments in AD. The innate immune response is characterized by pro-inflammatory (M1) activation of macrophages and subsequent production of specific cytokines, chemokines, and reactive intermediates, followed by resolution and alternative activation for anti-inflammatory signaling (M2a) and wound healing (M2c). We propose that microglial activation phenotypes are analogous to those of macrophages and that their activation plays a significant role in regulating neurogenesis in the brain. Microglia undergo a switch from an M2- to an M1-skewed activation phenotype during aging. This review will assess the neuroimmunological studies that led to characterization of the different microglial activation states in AD mouse models. It will also discuss the roles of microglial activation on neurogenesis in AD and propose anti-inflammatory molecules as exciting therapeutic targets for research. Molecules such as interleukin-4 and CD200 have proven to be important anti-inflammatory mediators in the regulation of neuroinflammation in the brain, which will be discussed in detail for their therapeutic potential.
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Affiliation(s)
- Megan M. Varnum
- Laboratory of Molecular NeuroTherapeutics, Boston University School of Medicine, Boston, Massachusetts, USA
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts, USA
- Program in Biomolecular Pharmacology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Tsuneya Ikezu
- Laboratory of Molecular NeuroTherapeutics, Boston University School of Medicine, Boston, Massachusetts, USA
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, Massachusetts, USA
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA
- Alzheimer’s Disease Center, Boston University School of Medicine, Boston, Massachusetts, USA
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40
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Salomone S, Caraci F, Leggio GM, Fedotova J, Drago F. New pharmacological strategies for treatment of Alzheimer's disease: focus on disease modifying drugs. Br J Clin Pharmacol 2012; 73:504-17. [PMID: 22035455 DOI: 10.1111/j.1365-2125.2011.04134.x] [Citation(s) in RCA: 202] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Current approved drug treatments for Alzheimer disease (AD) include cholinesterase inhibitors (donepezil, rivastigmine, galantamine) and the NMDA receptor antagonist memantine. These drugs provide symptomatic relief but poorly affect the progression of the disease. Drug discovery has been directed, in the last 10 years, to develop 'disease modifying drugs' hopefully able to counteract the progression of AD. Because in a chronic, slow progressing pathological process, such as AD, an early start of treatment enhances the chance of success, it is crucial to have biomarkers for early detection of AD-related brain dysfunction, usable before clinical onset. Reliable early biomarkers need therefore to be prospectively tested for predictive accuracy, with specific cut off values validated in clinical practice. Disease modifying drugs developed so far include drugs to reduce β amyloid (Aβ) production, drugs to prevent Aβ aggregation, drugs to promote Aβ clearance, drugs targeting tau phosphorylation and assembly and other approaches. Unfortunately none of these drugs has demonstrated efficacy in phase 3 studies. The failure of clinical trials with disease modifying drugs raises a number of questions, spanning from methodological flaws to fundamental understanding of AD pathophysiology and biology. Recently, new diagnostic criteria applicable to presymptomatic stages of AD have been published. These new criteria may impact on drug development, such that future trials on disease modifying drugs will include populations susceptible to AD, before clinical onset. Specific problems with completed trials and hopes with ongoing trials are discussed in this review.
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Affiliation(s)
- Salvatore Salomone
- Department of Clinical and Molecular Biomedicine, Section of Pharmacology and Biochemistry Department of Formative Processes, University of Catania, Viale Andrea Doria 6, Catania, Italy
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Allen SJ, Watson JJ, Dawbarn D. The neurotrophins and their role in Alzheimer's disease. Curr Neuropharmacol 2011; 9:559-73. [PMID: 22654716 PMCID: PMC3263452 DOI: 10.2174/157015911798376190] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Revised: 08/19/2010] [Accepted: 08/19/2010] [Indexed: 12/15/2022] Open
Abstract
Besides being essential for correct development of the vertebrate nervous system the neurotrophins also play a vital role in adult neuron survival, maintenance and regeneration. In addition they are implicated in the pathogenesis of certain neurodegenerative diseases, and may even provide a therapeutic solution for some. In particular there have been a number of studies on the involvement of nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) in the development of Alzheimer's disease. This disease is of growing concern as longevity increases worldwide, with little treatment available at the moment to alleviate the condition. Memory loss is one of the earliest symptoms associated with Alzheimer's disease. The brain regions first affected by pathology include the hippocampus, and also the entorhinal cortex and basal cholinergic nuclei which project to the hippocampus; importantly, all these areas are required for memory formation. Both NGF and BDNF are affected early in the disease and this is thought to initiate a cascade of events which exacerbates pathology and leads to the symptoms of dementia. This review briefly describes the pathology, symptoms and molecular processes associated with Alzheimer's disease; it discusses the involvement of the neurotrophins, particularly NGF and BDNF, and their receptors, with changes in BDNF considered particularly in the light of its importance in synaptic plasticity. In addition, the possibilities of neurotrophin-based therapeutics are evaluated.
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Affiliation(s)
- Shelley J Allen
- Dorothy Hodgkin Building, School of Clinical Sciences, University of Bristol, Bristol BS1 3NY, UK
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Götz J, Gladbach A, Pennanen L, van Eersel J, Schild A, David D, Ittner LM. Animal models reveal role for tau phosphorylation in human disease. Biochim Biophys Acta Mol Basis Dis 2010; 1802:860-71. [DOI: 10.1016/j.bbadis.2009.09.008] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 09/03/2009] [Accepted: 09/07/2009] [Indexed: 12/18/2022]
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Hébert SS, Papadopoulou AS, Smith P, Galas MC, Planel E, Silahtaroglu AN, Sergeant N, Buée L, De Strooper B. Genetic ablation of Dicer in adult forebrain neurons results in abnormal tau hyperphosphorylation and neurodegeneration. Hum Mol Genet 2010; 19:3959-69. [PMID: 20660113 DOI: 10.1093/hmg/ddq311] [Citation(s) in RCA: 243] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Type III RNase Dicer is responsible for the maturation and function of microRNA (miRNA) molecules in the cell. It is now well-documented that Dicer and the fine-tuning of the miRNA gene network are important for neuronal integrity. However, the underlying mechanisms involved in neuronal death, particularly in the adult brain, remain poorly defined. Here we show that the absence of Dicer in the adult forebrain is accompanied by a mixed neurodegenerative phenotype. Although neuronal loss is observed in the hippocampus, cellular shrinkage is predominant in the cortex. Interestingly, neuronal degeneration coincides with the hyperphosphorylation of endogenous tau at several epitopes previously associated with neurofibrillary pathology. Transcriptome analysis of enzymes involved in tau phosphorylation identified ERK1 as one of the candidate kinases responsible for this event in vivo. We further demonstrate that miRNAs belonging to the miR-15 family are potent regulators of ERK1 expression in mouse neuronal cells and co-expressed with ERK1/2 in vivo. Finally, we show that miR-15a is specifically downregulated in Alzheimer's disease brain. In summary, these results support the hypothesis that changes in the miRNA network may contribute to a neurodegenerative phenotype by affecting tau phosphorylation.
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Anoop A, Singh PK, Jacob RS, Maji SK. CSF Biomarkers for Alzheimer's Disease Diagnosis. Int J Alzheimers Dis 2010; 2010. [PMID: 20721349 PMCID: PMC2915796 DOI: 10.4061/2010/606802] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 04/27/2010] [Indexed: 01/12/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia that affects several million people worldwide. The major neuropathological hallmarks of AD are the presence of extracellular amyloid plaques that are composed of Aβ40 and Aβ42 and intracellular neurofibrillary tangles (NFT), which is composed of hyperphosphorylated protein Tau. While the amyloid plaques and NFT could define the disease progression involving neuronal loss and dysfunction, significant cognitive decline occurs before their appearance. Although significant advances in neuroimaging techniques provide the structure and physiology of brain of AD cases, the biomarker studies based on cerebrospinal fluid (CSF) and plasma represent the most direct and convenient means to study the disease progression. Biomarkers are useful in detecting the preclinical as well as symptomatic stages of AD. In this paper, we discuss the recent advancements of various biomarkers with particular emphasis on CSF biomarkers for monitoring the early development of AD before significant cognitive dysfunction.
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Affiliation(s)
- A Anoop
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
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Massoud F, Gauthier S. Update on the pharmacological treatment of Alzheimer's disease. Curr Neuropharmacol 2010; 8:69-80. [PMID: 20808547 PMCID: PMC2866463 DOI: 10.2174/157015910790909520] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 11/25/2009] [Accepted: 12/08/2009] [Indexed: 01/12/2023] Open
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder. Worldwide prevalence of the disease is estimated at more than 24 million cases. With aging of populations, this number will likely increase to more than 80 million cases by the year 2040. The annual incidence worldwide is estimated at 4.6 million cases which is the equivalent of one new case every seven seconds! The pathophysiology of AD is complex and largely misunderstood. It is thought to start with the accumulation of beta-amyloid (αβ) that leads to deposition of insoluble neuritic or senile plaques. Secondary events in this "amyloid cascade" include hyperphosphorylation of the protein tau into neurofibrillary tangles, inflammation, oxidation, and excitotoxicity that eventually cause activation of apoptotis, cell death and neurotransmitter deficits. This review will briefly summarize recent advances in the pathophysiology of AD and focus on the pharmacological treatment of the cognitive and functional symptoms of AD. It will discuss the roles of vascular prevention, cholinesterase inhibitors and an NMDA-antagonist in the management of AD. It will address the issues thought to be related to the lack of persistence or discontinuation of therapy with cholinesterase inhibitors shown in recent studies and some of the solutions proposed. These include setting realistic expectations in light of a neurodegenerative condition and available symptomatic treatments, slowly titrating medications, and using alternate routes of administration. Finally, it will introduce future therapeutic options currently under study.
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Affiliation(s)
- Fadi Massoud
- Department of Medicine, University of Montreal, Centre Hospitalier de l'Université de Montréal (CHUM), Hôpital Notre-Dame, Service de Gériatrie, 1560 Sherbrooke Est, Montreal, Quebec, H2L 4M1.
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Maarouf CL, Andacht TM, Kokjohn TA, Castaño EM, Sue LI, Beach TG, Roher AE. Proteomic analysis of Alzheimer's disease cerebrospinal fluid from neuropathologically diagnosed subjects. Curr Alzheimer Res 2009; 6:399-406. [PMID: 19689240 DOI: 10.2174/156720509788929318] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A crucial need exists for reliable Alzheimer's disease (AD) diagnostic and prognostic tests. Given its intimate communication with the brain, the cerebrospinal fluid (CSF) has been surveyed intensively for reliable AD biomarkers. The heterogeneity of AD pathology and the unavoidable difficulties associated with the clinical diagnosis and differentiation of this dementia from other pathologies have confounded biomarker studies in antemortem CSF samples. Using postmortem ventricular CSF (V-CSF) pools, two-dimensional difference gel electrophoresis (2D DIGE) analyses revealed a set of proteins that showed significant differences between neuropathologically-diagnosed AD and elderly non-demented controls (NDC), as well as subjects with non-AD dementias. The 2D DIGE system identified a set of 21 different protein biomarkers. This panel of proteins probably reflects fundamental pathological changes that are divergent from both normal aging and non-AD dementias.
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Affiliation(s)
- Chera L Maarouf
- The Longtine Center for Molecular Biology and Genetics, Sun Health Research Institute, Sun City, Arizona 85351, USA
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Wai MSM, Liang Y, Shi C, Cho EYP, Kung HF, Yew DT. Co-localization of hyperphosphorylated tau and caspases in the brainstem of Alzheimer's disease patients. Biogerontology 2008; 10:457-69. [PMID: 18946722 DOI: 10.1007/s10522-008-9189-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2008] [Accepted: 10/07/2008] [Indexed: 11/25/2022]
Abstract
Hyperphosphorylation of microtubule associated protein tau had limited studies in Alzheimer's disease (AD) brainstem. We compared the distribution and number of neurons with hyperphosphorylated tau in two age groups of AD brainstems with mean ages of 65.4 +/- 5.7 and 91.1 +/- 6.4 years. The degree of co-localization of hyperphosphorylated tau positive cells with either cleaved caspase-3 or cleaved caspase-6 was also quantified. Results showed hyperphosphorylated tau mainly occurred in hypoglossal, dorsal motor vagal, trigeminal sensory/motor nuclei as well as in dorsal raphe, locus coeruleus and substantia nigra. Older AD brainstem consistently had higher density of hyperphosphorylated tau cells. Up to 70% of tau positive cells also displayed either cleaved caspase-3 or caspase-6, and the number of co-localized tau cells in each caspase subfamily group was always higher in older aged group. Some hyperphosphorylated tau cells with cleaved caspases had TUNEL positive nuclei. These findings suggest that these latter cells went through the apoptotic process or DNA fragmentation.
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Affiliation(s)
- Maria Sen Mun Wai
- Department of Anatomy, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
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Deters N, Ittner LM, Götz J. Divergent phosphorylation pattern of tau in P301L tau transgenic mice. Eur J Neurosci 2008; 28:137-47. [PMID: 18662339 DOI: 10.1111/j.1460-9568.2008.06318.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Aggregates of hyperphosphorylated tau are prominent in brains of patients with Alzheimer's disease or frontotemporal dementia (FTD). They have been reproduced in animal models following the identification of tau mutations in familial cases of FTD. This includes our previously generated transgenic model, pR5, which expresses FTD (P301L) mutant tau in neurons. The mice are characterized by tau aggregation including tangle (NFT) formation, memory impairment and mitochondrial dysfunction. In 8-month-old mice, S422 phosphorylation of tau is linked to NFT formation, however, a detailed analysis of tau solubility, phosphorylation and aggregation has not been done nor have the mice been monitored until a high age. Here, we undertook an analysis by immunohistochemistry, Gallyas impregnation and Western blotting of brains from 3 month- up to 20 month-old mice. NFTs first appeared at 6 months in the amygdala, followed by the CA1 region of the hippocampus. As the mice get older, the solubility of tau is decreased as determined by sequential extractions. Histological analysis revealed increased phosphorylation at the AT180, AT270 and 12E8 epitopes with ageing. The numbers of AT8-positive neurons increased from 3 to 6 months old. However, whereas S422 appeared only late and concomitantly with NFT formation, the only neurons left with AT8-reactivity at 20 months were those that had undergone NFT formation. As hyperphosphorylated tau continued to accumulate, the lack of AT8-reactivity suggests regulatory mechanisms in specifically dephosphorylating the AT8 epitope in the remaining neurons. Thus, differential regulation of phosphorylation is important for NFT formation in neurodegenerative diseases with tau pathology.
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Affiliation(s)
- Natasha Deters
- Alzheimer's and Parkinson's Disease Laboratory, Brain & Mind Research Institute, University of Sydney, 100 Mallett St, Camperdown, NSW 2050, Australia
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Mondragón-Rodríguez S, Basurto-Islas G, Santa-Maria I, Mena R, Binder LI, Avila J, Smith MA, Perry G, García-Sierra F. Cleavage and conformational changes of tau protein follow phosphorylation during Alzheimer's disease. Int J Exp Pathol 2008; 89:81-90. [PMID: 18336525 DOI: 10.1111/j.1365-2613.2007.00568.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Phosphorylation, cleavage and conformational changes in tau protein all play pivotal roles during Alzheimer's disease (AD). In an effort to determine the chronological sequence of these changes, in this study, using confocal microscopy, we compared phosphorylation at several sites (Ser(199/202/396/404/422)-Thr(205) and the second repeat domain), cleavage of tau (D(421)) and the canonical conformational Alz-50 epitope. While all of these posttranslational modifications are found in neurofibrillary tangles (NFTs) at all stages of the disease, we found significantly higher numbers of phospho-tau positive NFTs when compared with cleaved tau (P = 0.006 in Braak III; P = 0.002 in Braak IV; P = 0.012 in Braak V) or compared with the Alz-50 epitope (P < 0.05). Consistent with these findings, in a double transgenic mice model (Tet/GSK-3beta/VLW) overexpressing the enzyme glycogen synthase kinase-3beta (GSK-3beta) and tau with a triple FTDP-17 mutation (VLW) with AD-like neurodegeneration, phosphorylation at sites Ser(199/202)-Thr(205) was greater than truncated tau. Taken together, these data strongly support the notion that the conformational changes and truncation of tau occur after the phosphorylation of tau. We propose two probable pathways for the pathological processing of tau protein during AD, either phosphorylation and cleavage of tau followed by the Alz-50 conformational change or phosphorylation followed by the conformational change and cleavage as the last step.
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Chen S, Li B, Grundke-Iqbal I, Iqbal K. I1PP2A affects tau phosphorylation via association with the catalytic subunit of protein phosphatase 2A. J Biol Chem 2008; 283:10513-21. [PMID: 18245083 DOI: 10.1074/jbc.m709852200] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
In Alzheimer disease (AD) brain, the level of I (1)(PP2A), a 249-amino acid long endogenous inhibitor of protein phosphatase 2A (PP2A), is increased, the activity of the phosphatase is decreased, and the microtubule-associated protein Tau is abnormally hyperphosphorylated. However, little is known about the detailed regulatory mechanism by which PP2A activity is inhibited by I (1)(PP2A) and the consequent events in mammalian cells. In this study, we found that both I (1)(PP2A) and its N-terminal half I (1)(PP2A(1-120)), but neither I (1)(PP2A(1-163)) nor I (1)(PP2A(164-249)), inhibited PP2A activity in vitro, suggesting an autoinhibition by amino acid residues 121-163 and its neutralization by the C-terminal region. Furthermore, transfection of NIH3T3 cells produced a dose-dependent inhibition of PP2A activity by I (1)(PP2A)(1). I (PP2A) and PP2A were found to colocalize in PC12 cells. I (1)(PP2A) could only interact with the catalytic subunit of PP2A (PP2Ac) and had no interaction with the regulatory subunits of PP2A (PP2A-A or PP2A-B) using a glutathione S-transferase-pulldown assay. The interaction was further confirmed by coimmunoprecipitation of I (1)(PP2A) and PP2Ac from lysates of transiently transfected NIH3T3 cells. The N-terminal isotype specific region of I (1)(PP2A) was required for its association with PP2Ac as well as PP2A inhibition. In addition, the phosphorylation of Tau was significantly increased in PC12/Tau441 cells transiently transfected with full-length I (1)(PP2A) and with PP2Ac-interacting I (1)(PP2A) deletion mutant 1-120 (I (1)(PP2A)DeltaC2). Double immunofluorescence staining showed that I (1)(PP2A) and I (1)(PP2A)DeltaC2 increased Tau phosphorylation and impaired the microtubule network and neurite outgrowth in PC12 cells treated with nerve growth factor.
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Affiliation(s)
- She Chen
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
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