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Glineburg MR, Yildirim E, Gomez N, Rodriguez G, Pak J, Li X, Altheim C, Waksmacki J, McInerney GM, Barmada SJ, Todd PK. Stress granule formation helps to mitigate neurodegeneration. Nucleic Acids Res 2024; 52:9745-9759. [PMID: 39106168 PMCID: PMC11381325 DOI: 10.1093/nar/gkae655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 05/28/2024] [Accepted: 07/17/2024] [Indexed: 08/09/2024] Open
Abstract
Cellular stress pathways that inhibit translation initiation lead to transient formation of cytoplasmic RNA/protein complexes known as stress granules. Many of the proteins found within stress granules and the dynamics of stress granule formation and dissolution are implicated in neurodegenerative disease. Whether stress granule formation is protective or harmful in neurodegenerative conditions is not known. To address this, we took advantage of the alphavirus protein nsP3, which selectively binds dimers of the central stress granule nucleator protein G3BP and markedly reduces stress granule formation without directly impacting the protein translational inhibitory pathways that trigger stress granule formation. In Drosophila and rodent neurons, reducing stress granule formation with nsP3 had modest impacts on lifespan even in the setting of serial stress pathway induction. In contrast, reducing stress granule formation in models of ataxia, amyotrophic lateral sclerosis and frontotemporal dementia largely exacerbated disease phenotypes. These data support a model whereby stress granules mitigate, rather than promote, neurodegenerative cascades.
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Affiliation(s)
- M Rebecca Glineburg
- Biological Sciences, Schmid College of Science and Technology, Chapman University, 1 University Drive, Orange, CA 92866, USA
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
| | - Evrim Yildirim
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
| | - Nicolas Gomez
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
- Cell and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Genesis Rodriguez
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Jaclyn Pak
- Biological Sciences, Schmid College of Science and Technology, Chapman University, 1 University Drive, Orange, CA 92866, USA
| | - Xingli Li
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
| | - Christopher Altheim
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
| | - Jacob Waksmacki
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
| | - Gerald M McInerney
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm 17165, Sweden
| | - Sami J Barmada
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
| | - Peter K Todd
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, BSRB48109-2200, Ann Arbor, MI 4005, USA
- Veterans Affairs Medical Center, Ann Arbor, MI, USA
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2
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Liu Y, Xu C, Gu R, Han R, Li Z, Xu X. Endoplasmic reticulum stress in diseases. MedComm (Beijing) 2024; 5:e701. [PMID: 39188936 PMCID: PMC11345536 DOI: 10.1002/mco2.701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 07/30/2024] [Accepted: 07/31/2024] [Indexed: 08/28/2024] Open
Abstract
The endoplasmic reticulum (ER) is a key organelle in eukaryotic cells, responsible for a wide range of vital functions, including the modification, folding, and trafficking of proteins, as well as the biosynthesis of lipids and the maintenance of intracellular calcium homeostasis. A variety of factors can disrupt the function of the ER, leading to the aggregation of unfolded and misfolded proteins within its confines and the induction of ER stress. A conserved cascade of signaling events known as the unfolded protein response (UPR) has evolved to relieve the burden within the ER and restore ER homeostasis. However, these processes can culminate in cell death while ER stress is sustained over an extended period and at elevated levels. This review summarizes the potential role of ER stress and the UPR in determining cell fate and function in various diseases, including cardiovascular diseases, neurodegenerative diseases, metabolic diseases, autoimmune diseases, fibrotic diseases, viral infections, and cancer. It also puts forward that the manipulation of this intricate signaling pathway may represent a novel target for drug discovery and innovative therapeutic strategies in the context of human diseases.
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Affiliation(s)
- Yingying Liu
- Department of Aviation Clinical Medicine, Air Force Medical CenterPLABeijingChina
| | - Chunling Xu
- School of Pharmaceutical SciencesTsinghua UniversityBeijingChina
| | - Renjun Gu
- School of Chinese MedicineNanjing University of Chinese MedicineNanjingChina
- Department of Gastroenterology and HepatologyJinling HospitalMedical School of Nanjing UniversityNanjingChina
| | - Ruiqin Han
- State Key Laboratory of Medical Molecular BiologyDepartment of Biochemistry and Molecular BiologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Ziyu Li
- School of Acupuncture and TuinaSchool of Regimen and RehabilitationNanjing University of Chinese MedicineNanjingChina
| | - Xianrong Xu
- Department of Aviation Clinical Medicine, Air Force Medical CenterPLABeijingChina
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Glineburg MR, Yildirim E, Gomez N, Li X, Pak J, Altheim C, Waksmacki J, McInerney G, Barmada SJ, Todd PK. Stress granule formation helps to mitigate neurodegeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.566060. [PMID: 37986813 PMCID: PMC10659376 DOI: 10.1101/2023.11.07.566060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Cellular stress pathways that inhibit translation initiation lead to transient formation of cytoplasmic RNA/protein complexes known as stress granules. Many of the proteins found within stress granules and the dynamics of stress granule formation and dissolution are implicated in neurodegenerative disease. Whether stress granule formation is protective or harmful in neurodegenerative conditions is not known. To address this, we took advantage of the alphavirus protein nsP3, which selectively binds dimers of the central stress granule nucleator protein G3BP (rin in Drosophila) and markedly reduces stress granule formation without directly impacting the protein translational inhibitory pathways that trigger stress granule formation. In Drosophila and rodent neurons, reducing stress granule formation with nsP3 had modest impacts on lifespan even in the setting of serial stress pathway induction. In contrast, reducing stress granule formation in models of ataxia, amyotrophic lateral sclerosis and frontotemporal dementia largely exacerbated disease phenotypes. These data support a model whereby stress granules mitigate, rather than promote, neurodegenerative cascades.
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Affiliation(s)
- M. Rebecca Glineburg
- Biological Sciences, Schmid College of Science and Technology, Chapman University, 450 N. Center St, Orange, CA 92866
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
| | - Evrim Yildirim
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
| | - Nicolas Gomez
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden
| | - Xingli Li
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
| | - Jaclyn Pak
- Biological Sciences, Schmid College of Science and Technology, Chapman University, 450 N. Center St, Orange, CA 92866
| | - Christopher Altheim
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
| | - Jacob Waksmacki
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
| | - Gerald McInerney
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 17165, Sweden
| | - Sami J. Barmada
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
| | - Peter K. Todd
- Department of Neurology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 4005 BSRB48109-2200, USA
- Veterans Affairs Medical Center, Ann Arbor, MI, USA
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Liang T, Xue F, Hang W, Wen B, Zhang Q, Chen J, Liu X, Chen J. Neuron-Specific Apolipoprotein E4 (1-272) Fragment Induces Tau Hyperphosphorylation and Axonopathy via Triggering Endoplasmic Reticulum Stress. J Alzheimers Dis 2020; 71:597-611. [PMID: 31424401 DOI: 10.3233/jad-190419] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Apolipoprotein (apo) E4 is the major genetic risk factor for Alzheimer's disease (AD). It is shown that apoE4 preferentially undergoes aberrant cleavage in neurons, yielding neurotoxic C-terminal-truncated apoE4 fragment. Endoplasmic reticulum (ER) stress has also been known to be involved in the pathogenesis of AD. However, little is known about the contribution of ER stress to the neurotoxicity of apoE4 fragment. In the present study, we established the neuron-specific expression human C-terminal-truncated apoE4(1-272) fragment transgenic mice and also transfected apoE4(1-272) fragment in neuroblastoma N2a cells. We found that human apoE4(1-272) fragment could trigger ER stress as evidenced by increasing the expression of ER stress markers both in vivo and in vitro. Meanwhile, the apoE4(1-272) transgenic mice presented obviously AD-like neuropathological changes, including the impairment of spatial learning and memory, prominent axonal morphological changes, and hyperphosphorylation of tau. At the same time, we also found that glycogen synthase kinase-3 activities were significantly increased. Furthermore, these neuropathological changes, especially tau hyperphosphorylation and axonal transport impairment, were significantly rescued by the ER stress protector 4-phenylbutyric acid (4-PBA) in apoE4(1-272)-transfected N2a cells. Pretreatment with 4-PBA not only decreased the protein expression of immunoglobulin binding protein (BiP) and C/EBP-homologous protein (CHOP), but also significantly reversed these defects in axonal transport. These results suggested that the neurotoxic effects of apoE4(1-272) fragment found in AD subjects, at least in part, through triggering ER stress and inducing tau hyperphosphorylation, led to the enduring impairment of axonal transport.
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Affiliation(s)
- Tao Liang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Department of Clinical laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Feixiao Xue
- Department of Clinical laboratory, Xi'an No.3 Hospital, Xi'an, Shanxi, China
| | - Weijian Hang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Bin Wen
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qianying Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jiehui Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaofeng Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Department of Laboratory Medicine and Gene Diagnostic Laboratory, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Juan Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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Hafycz JM, Naidoo NN. Sleep, Aging, and Cellular Health: Aged-Related Changes in Sleep and Protein Homeostasis Converge in Neurodegenerative Diseases. Front Aging Neurosci 2019; 11:140. [PMID: 31244649 PMCID: PMC6579877 DOI: 10.3389/fnagi.2019.00140] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 05/23/2019] [Indexed: 01/17/2023] Open
Abstract
Many neurodegenerative diseases manifest in an overall aged population, the pathology of which is hallmarked by abnormal protein aggregation. It is known that across aging, sleep quality becomes less efficient and protein homeostatic regulatory mechanisms deteriorate. There is a known relationship between extended wakefulness and poorly consolidated sleep and an increase in cellular stress. In an aged population, when sleep is chronically poor, and proteostatic regulatory mechanisms are less efficient, the cell is inundated with misfolded proteins and suffers a collapse in homeostasis. In this review article, we explore the interplay between aging, sleep quality, and proteostasis and how these processes are implicated in the development and progression of neurodegenerative diseases like Alzheimer's disease (AD). We also present data suggesting that reducing cellular stress and improving proteostasis and sleep quality could serve as potential therapeutic solutions for the prevention or delay in the progression of these diseases.
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Affiliation(s)
- Jennifer M Hafycz
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Pennsylvania, PA, United States
| | - Nirinjini N Naidoo
- Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Pennsylvania, PA, United States
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Hashimoto S, Saido TC. Critical review: involvement of endoplasmic reticulum stress in the aetiology of Alzheimer's disease. Open Biol 2019; 8:rsob.180024. [PMID: 29695619 PMCID: PMC5936719 DOI: 10.1098/rsob.180024] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/03/2018] [Indexed: 12/18/2022] Open
Abstract
The endoplasmic reticulum (ER) stress response is regarded as an important process in the aetiology of Alzheimer's disease (AD). The accumulation of pathogenic misfolded proteins and the disruption of intracellular calcium (Ca2+) signalling are considered to be fundamental mechanisms that underlie the induction of ER stress, leading to neuronal cell death. Indeed, a number of studies have proposed molecular mechanisms linking ER stress to AD pathogenesis based on results from in vitro systems and AD mouse models. However, stress responsivity was largely different between each mouse model, even though all of these models display AD-related pathologies. While several reports have shown elevated ER stress responses in amyloid precursor protein (APP) and presenilin 1 (PS1) double-transgenic (Tg) AD mouse models, we and other groups, in contrast, observed no such ER stress response in APP-single-Tg or App-knockin mice. Therefore, it is debatable whether the ER stress observed in APP and PS1 double-Tg mice is due to AD pathology. From these findings, the roles of ER stress in AD pathogenesis needs to be carefully addressed in future studies. In this review, we summarize research detailing the relationship between ER stress and AD, and analyse the results in detail.
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Affiliation(s)
- Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Fe 3+ Facilitates Endocytic Internalization of Extracellular Aβ 1-42 and Enhances Aβ 1-42-Induced Caspase-3/Caspase-4 Activation and Neuronal Cell Death. Mol Neurobiol 2018; 56:4812-4819. [PMID: 30402707 DOI: 10.1007/s12035-018-1408-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 10/24/2018] [Indexed: 12/12/2022]
Abstract
Amyloid β (Aβ) peptide is a critical causative factor in Alzheimer's disease (AD) and of a variety of fragmented Aβ peptides Aβ1-42 thought to exhibit the most neurotoxic effect. The present study investigated the effects of Fe3+ on Aβ1-42 internalization and Aβ1-42-induced caspase activation and neurotoxicity using mouse hippocampal slices and cultured PC-12 cells. Extracellularly applied Aβ1-42 increased the cell-associated Aβ1-42 levels in a concentration-dependent manner, and the effect was enhanced by adding Fe3+. Fe3+-induced enhancement of the cell-associated Aβ1-42 levels was significantly inhibited by the endocytosis inhibitors dynasore and methyl-β-cyclodextrin. Aβ1-42 reduced PC-12 cell viability in a concentration-dependent manner, and further reduction of the cell viability was obtained with Fe3+. Aβ1-42-induced reduction of cell viability was not affected by A187, an antagonist of amylin-3 receptor. Aβ1-42 activated caspase-3, caspase-4, and caspase-8 to a variety of degrees and Fe3+ further enhanced Aβ1-42-induced activation of caspase-3 and caspase-4. Taken together, these results indicate that Fe3+ accelerates endocytic internalization of extracellular Aβ1-42, enhances Aβ1-42-induced caspase-3/caspase-4 activation, and promotes Aβ1-42-induced neuronal cell death, regardless of amylin receptor.
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Abstract
The clinical manifestation of neurodegenerative diseases is initiated by the selective alteration in the functionality of distinct neuronal populations. The pathology of many neurodegenerative diseases includes accumulation of misfolded proteins in the brain. In physiological conditions, the proteostasis network maintains normal protein folding, trafficking and degradation; alterations in this network - particularly disturbances to the function of endoplasmic reticulum (ER) - are thought to contribute to abnormal protein aggregation. ER stress triggers a signalling reaction known as the unfolded protein response (UPR), which induces adaptive programmes that improve protein folding and promote quality control mechanisms and degradative pathways or can activate apoptosis when damage is irreversible. In this Review, we discuss the latest advances in defining the functional contribution of ER stress to brain diseases, including novel evidence that relates the UPR to synaptic function, which has implications for cognition and memory. A complex concept is emerging wherein the consequences of ER stress can differ drastically depending on the disease context and the UPR signalling pathway that is altered. Strategies to target specific components of the UPR using small molecules and gene therapy are in development, and promise interesting avenues for future interventions to delay or stop neurodegeneration.
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Thummayot S, Tocharus C, Suksamrarn A, Tocharus J. Neuroprotective effects of cyanidin against Aβ-induced oxidative and ER stress in SK-N-SH cells. Neurochem Int 2016; 101:15-21. [PMID: 27697517 DOI: 10.1016/j.neuint.2016.09.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 09/10/2016] [Accepted: 09/12/2016] [Indexed: 11/29/2022]
Abstract
This study evaluated the mechanisms underlying the protective effect of cyanidin against Aβ25-35-induced neuronal cell death in SK-N-SH cells. Aβ25-35-induced neurotoxicity is characterized by a decrease in cell viability, inducing the expression of endoplasmic reticulum (ER) stress proteins; an increase in intracellular reactive oxygen species (ROS) production; and an increase in intracellular calcium release. Aβ25-35 also induces neuronal toxicity through the disturbance of ER calcium levels. Pretreatment with cyanidin significantly attenuated the Aβ25-35-induced loss of cell viability, reducing the expression of endoplasmic reticulum (ER) stress response proteins with regard to the down-regulation of the expression levels of 78 kDa glucose regulated protein (Grp78), phosphorylated forms of pancreatic ER elF2α kinase (PERK), eukaryotic initiation factor 2 α (eIF2α), and inositol-requiring enzyme 1 (IRE1), and the expression levels of X-box binding protein 1 (XBP-1), activating transcription factor 6 (ATF6), and CCAAT/enhancer binding protein homologous transcription factor (C/EBP) homologous protein (CHOP); decreased intracellular ROS production; decreased intracellular calcium release; and reduced down-regulation of the protein expression levels of calpain and cleaved caspase-12. This result suggests that cyanidin may be an alternative agent in preventing neurodegenerative diseases.
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Affiliation(s)
- Sarinthorn Thummayot
- Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Chainarong Tocharus
- Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Apichart Suksamrarn
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand
| | - Jiraporn Tocharus
- Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.
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The combination of 1α,25dihydroxyvitaminD3 with resveratrol improves neuronal degeneration by regulating endoplasmic reticulum stress, insulin signaling and inhibiting tau hyperphosphorylation in SH-SY5Y cells. Food Chem Toxicol 2016; 93:32-40. [DOI: 10.1016/j.fct.2016.04.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 03/29/2016] [Accepted: 04/26/2016] [Indexed: 11/21/2022]
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Perri ER, Thomas CJ, Parakh S, Spencer DM, Atkin JD. The Unfolded Protein Response and the Role of Protein Disulfide Isomerase in Neurodegeneration. Front Cell Dev Biol 2016; 3:80. [PMID: 26779479 PMCID: PMC4705227 DOI: 10.3389/fcell.2015.00080] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/03/2015] [Indexed: 12/11/2022] Open
Abstract
The maintenance and regulation of proteostasis is a critical function for post-mitotic neurons and its dysregulation is increasingly implicated in neurodegenerative diseases. Despite having different clinical manifestations, these disorders share similar pathology; an accumulation of misfolded proteins in neurons and subsequent disruption to cellular proteostasis. The endoplasmic reticulum (ER) is an important component of proteostasis, and when the accumulation of misfolded proteins occurs within the ER, this disturbs ER homeostasis, giving rise to ER stress. This triggers the unfolded protein response (UPR), distinct signaling pathways that whilst initially protective, are pro-apoptotic if ER stress is prolonged. ER stress is increasingly implicated in neurodegenerative diseases, and emerging evidence highlights the complexity of the UPR in these disorders, with both protective and detrimental components being described. Protein Disulfide Isomerase (PDI) is an ER chaperone induced during ER stress that is responsible for the formation of disulfide bonds in proteins. Whilst initially considered to be protective, recent studies have revealed unconventional roles for PDI in neurodegenerative diseases, distinct from its normal function in the UPR and the ER, although these mechanisms remain poorly defined. However, specific aspects of PDI function may offer the potential to be exploited therapeutically in the future. This review will focus on the evidence linking ER stress and the UPR to neurodegenerative diseases, with particular emphasis on the emerging functions ascribed to PDI in these conditions.
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Affiliation(s)
- Emma R Perri
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University Melbourne, VIC, Australia
| | - Colleen J Thomas
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University Melbourne, VIC, Australia
| | - Sonam Parakh
- Department of Biomedical Sciences, Faculty of Medicine and Human Science, Macquarie University Sydney, NSW, Australia
| | - Damian M Spencer
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University Melbourne, VIC, Australia
| | - Julie D Atkin
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe UniversityMelbourne, VIC, Australia; Department of Biomedical Sciences, Faculty of Medicine and Human Science, Macquarie UniversitySydney, NSW, Australia
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12
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Jin Y, Tsuchiya A, Kanno T, Nishizaki T. Amyloid-β peptide increases cell surface localization of α7 ACh receptor to protect neurons from amyloid β-induced damage. Biochem Biophys Res Commun 2015; 468:157-60. [PMID: 26522221 DOI: 10.1016/j.bbrc.2015.10.141] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 10/26/2015] [Indexed: 11/27/2022]
Abstract
Amyloid-β peptide 1-42 (Aβ1-42) reduced PC-12 cell viability in a concentration (1-10 μM)- and treatment time (48-72 h)-dependent manner. Nicotine prevented Aβ1-42-induced PC-12 cell death, but conversely, the α7 ACh receptor antagonist α-bungarotoxin enhanced Aβ1-42-induced cell toxicity. Extracellularly applied Aβ1-42 significantly increased cell surface localization of α7 ACh receptor in PC-12 cells as compared with that for non-treated control cells. Cell surface localization of α7 ACh receptor in the brain of 5xFAD mouse, an animal model of Alzheimer's disease (AD), apparently increased in an age (1-12 months)-dependent manner in association with increased accumulation of Aβ1-42 in the plasma membrane component. Taken together, these results indicate that Aβ1-42 promotes translocation of α7 ACh receptor towards the cell surface and that α7 ACh receptor rescues neuronal cells from Aβ1-42-induced damage.
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Affiliation(s)
- Yu Jin
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan
| | - Ayako Tsuchiya
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan
| | - Takeshi Kanno
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan
| | - Tomoyuki Nishizaki
- Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan.
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13
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Moussavi Nik SH, Newman M, Wilson L, Ebrahimie E, Wells S, Musgrave I, Verdile G, Martins RN, Lardelli M. Alzheimer's disease-related peptide PS2V plays ancient, conserved roles in suppression of the unfolded protein response under hypoxia and stimulation of γ-secretase activity. Hum Mol Genet 2015; 24:3662-78. [PMID: 25814654 DOI: 10.1093/hmg/ddv110] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/23/2015] [Indexed: 12/30/2022] Open
Abstract
The PRESENILIN1 and PRESENILIN2 genes encode structurally related proteases essential for γ-secretase activity. Of nearly 200 PRESENILIN mutations causing early onset, familial Alzheimer's disease (FAD) only the K115Efx10 mutation of PSEN2 causes truncation of the open reading frame. If translated, the truncated product would resemble a naturally occurring isoform of PSEN2 named PS2V that is induced by hypoxia and found at elevated levels in late onset Alzheimer's disease (AD) brains. The function of PS2V is largely unexplored. We show that zebrafish possess a PS2V-like isoform, PS1IV, produced from the fish's PSEN1 rather than PSEN2 orthologous gene. The molecular mechanism controlling formation of PS2V/PS1IV was probably present in the ancient common ancestor of the PSEN1 and PSEN2 genes. Human PS2V and zebrafish PS1IV have highly divergent structures but conserved abilities to stimulate γ-secretase activity and to suppress the unfolded protein response (UPR) under hypoxia. The putative protein truncation caused by K115Efx10 resembles PS2V in its ability to increase γ-secretase activity and suppress the UPR. This supports increased Aβ levels as a common link between K115Efx10 early onset AD and sporadic, late onset AD. The ability of mutant variants of PS2V to stimulate γ-secretase activity partially correlates with their ability to suppress the UPR. The cytosolic, transmembrane and luminal domains of PS2V are all critical to its γ-secretase and UPR-suppression activities. Our data support a model in which chronic hypoxia in aged brains promotes excessive Notch signalling and accumulation of Aβ that contribute to AD pathogenesis.
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Affiliation(s)
| | - Morgan Newman
- Department of Genetics and Evolution, School of Biological Sciences
| | - Lachlan Wilson
- Department of Genetics and Evolution, School of Biological Sciences
| | | | - Simon Wells
- Department of Genetics and Evolution, School of Biological Sciences
| | - Ian Musgrave
- Clinical and Experimental Pharmacology, University of Adelaide, Adelaide, SA 5005, Australia
| | - Giuseppe Verdile
- School of Biomedical Sciences, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia, Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, WA 6027, Australia and School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Ralph N Martins
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, WA 6027, Australia and School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Michael Lardelli
- Department of Genetics and Evolution, School of Biological Sciences,
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14
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Liu ZC, Chu J, Lin L, Song J, Ning LN, Luo HB, Yang SS, Shi Y, Wang Q, Qu N, Zhang Q, Wang JZ, Tian Q. SIL1 Rescued Bip Elevation-Related Tau Hyperphosphorylation in ER Stress. Mol Neurobiol 2015; 53:983-994. [PMID: 25575678 DOI: 10.1007/s12035-014-9039-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 11/30/2014] [Indexed: 12/20/2022]
Abstract
Endoplasmic reticulum (ER) stress has been indicated in the early stage of Alzheimer's disease (AD), in which tau hyperphosphorylation is one major pathological alteration. The elevation of binding immunoglobulin protein (Bip), an important ER chaperon, was reported in AD brain. It is important to study the roles of ER-related chaperons in tau hyperphosphorylation. In this research, increased Bip was found in the brains of the AD model mice (Tg2576) compared to the age-matched control mice. Meanwhile, deficiency of SIL1, an important co-chaperon of Bip, was observed in brains of Tg2576 mice and in ER stress both in vivo and in vitro. Then, we transfected Bip-EGFP plasmid into HEK293 cells stably expressing the longest human tau (HEK293/tau) or N2a cells and found that increased Bip induced tau hyperphosphorylation via activating glycogen synthase kinase-3β (GSK-3β), an important tau kinase, and increased the association with tau and GSK-3β. When we overexpressed SIL1 in Bip-transfected HEK293/tau cells and thapsigargin-treated HEK293/tau cells, significantly reduced tau hyperphosphorylation and GSK-3β activation were observed. These results suggested the important roles of ER-related chaperons, Bip and SIL1, in AD-like tau hyperphosphorylation.
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Affiliation(s)
- Zan-Chao Liu
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
- 2nd Hospital of Shijiazhuang, Shijiazhuang, 050051, China
| | - Jiang Chu
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Li Lin
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
- Hubei University of Traditional Chinese Medicine, Wuhan, 430061, China
| | - Jie Song
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Lin-Na Ning
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Hong-Bin Luo
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
- Medical School, Hubei University for Nationalities, Enshi, 445000, China
| | - Shu-Sheng Yang
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
- Hubei University of Traditional Chinese Medicine, Wuhan, 430061, China
| | - Yan Shi
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Qun Wang
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Na Qu
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Qi Zhang
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China
| | - Jian-Zhi Wang
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China.
| | - Qing Tian
- Department of Pathology and Pathophysiology, School of Basic Medicine, Tongji Medical College; Key Laboratory of Neurological Disease of National Education Ministry and Hubei Province, Institute of Brain Science, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, 430030, China.
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15
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Huang HC, Tang D, Lu SY, Jiang ZF. Endoplasmic reticulum stress as a novel neuronal mediator in Alzheimer's disease. Neurol Res 2014; 37:366-74. [PMID: 25310352 DOI: 10.1179/1743132814y.0000000448] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Alzheimer's disease (AD) is one of the most common types of progressive dementias. The typical neuropathological changes in AD include extracellular senile plaques, intracellular neurofibrillary tangles, and loss of neurons. The pathogenetic mechanism of this disease is not comprehensively understood yet. Recently, endoplasmic reticulum stress (ER stress) has been considered as a potential event involved in AD development. Some AD-related factors, such as misfolded protein and Ca(2+) depletion, could disrupt the homeostasis of ER lumen. In AD, the aggregated amyloid-beta peptide (Abeta) could induce ER stress in an assembly dependent way. The presenilin has been identified as a Ca(2+) channel. Mutations of presenilin could change the balance of Ca(2+) in ER lumen and thus disrupts the ER homeostasis. Furthermore, the ER stress could lead to cellular disorders like inflammation. Through activating the expression of inflammatory factors, ER stress triggers inflammatory response in AD pathology. Herein, we reviewed the recent progress of ER stress-induced unfolded protein response (UPR) and the roles of ER stress in AD pathological process.
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16
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Sanchez-Espinosa MP, Atienza M, Cantero JL. Sleep deficits in mild cognitive impairment are related to increased levels of plasma amyloid-β and cortical thinning. Neuroimage 2014; 98:395-404. [PMID: 24845621 DOI: 10.1016/j.neuroimage.2014.05.027] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Revised: 05/01/2014] [Accepted: 05/10/2014] [Indexed: 01/09/2023] Open
Abstract
Evidence suggests that amyloid-beta (Aβ) depositions parallel sleep deficits in Alzheimer's disease (AD). However, it remains unknown whether impaired sleep and changes in plasma Aβ levels are related in amnestic mild cognitive impairment (aMCI) subjects, and whether both markers are further associated with cortical thinning in canonical AD regions. To jointly address this issue, we investigated relationships between changes in physiological sleep and plasma Aβ concentrations in 21 healthy old (HO) adults and 21 aMCI subjects, and further assessed whether these two factors were associated with cortical loss in each group. aMCI, but not HO subjects, showed significant relationships between disrupted slow-wave sleep (SWS) and increased plasma levels of Aβ42. We also found that shortened rapid-eye movement (REM) sleep in aMCI correlated with thinning of the posterior cingulate, precuneus, and postcentral gyrus; whereas higher levels of Aβ40 and Aβ42 accounted for grey matter (GM) loss of posterior cingulate and entorhinal cortex, respectively. These results support preliminary relationships between Aβ burden and altered sleep physiology observed in animal models of AD amyloidosis, and provide precise cortical correlates of these changes in older adults with aMCI. Taken together, these findings open new research avenues on the combined role of sleep, peripheral Aβ levels and cortical integrity in tracking the progression from normal aging to early neurodegeneration.
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Affiliation(s)
- Mayely P Sanchez-Espinosa
- Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain
| | - Mercedes Atienza
- Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain
| | - Jose L Cantero
- Laboratory of Functional Neuroscience, Spanish Network of Excellence for Research on Neurodegenerative Diseases (CIBERNED), Pablo de Olavide University, Seville, Spain.
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17
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Rivabene R, Visentin S, Piscopo P, De Nuccio C, Crestini A, Svetoni F, Rosa P, Confaloni A. Thapsigargin affects presenilin-2 but not presenilin-1 regulation in SK-N-BE cells. Exp Biol Med (Maywood) 2013; 239:213-24. [PMID: 24363250 DOI: 10.1177/1535370213514317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Presenilin-1 (PS1) and presenilin-2 (PS2) are transmembrane proteins widely expressed in the central nervous system, which function as the catalytic subunits of γ-secretase, the enzyme that releases amyloid-β protein (Aβ) from ectodomain cleaved amyloid precursor protein (APP) by intramembrane proteolysis. Mutations in PS1, PS2, and Aβ protein precursor are involved in the etiology of familial Alzheimer's disease (FAD), while the cause of the sporadic form of AD (SAD) is still not known. However, since similar neuropathological changes have been observed in both FAD and SAD, a common pathway in the etiology of the disease has been suggested. Given that age-related deranged Ca(2+) regulation has been hypothesized to play a role in SAD pathogenesis via PS gene regulation and γ-secretase activity, we studied the in vitro regulation of PS1 and PS2 in the human neuron-like SK-N-BE cell line treated with the specific endoplasmic reticulum (ER) calcium ATPase inhibitor Thapsigargin (THG), to introduce intracellular Ca(2+) perturbations and mimic the altered Ca(2+) homeostasis observed in AD. Our results showed a consistent and significant down-regulation of PS2, while PS1 appeared to be unmodulated. These events were accompanied by oxidative stress and a number of morphological alterations suggestive of the induction of apoptotic machinery. The administration of the antioxidant N-acetylcysteine (NAC) did not revert the THG-induced effects reported, while treatment with the Ca(2+)-independent ER stressor Brefeldin A did not modulate basal PS1 and PS2 expression. Collectively, these results suggest that Ca(2+) fluctuation rather than ER stress and/or oxidative imbalance seems to play an essential role in PS2 regulation and confirm that, despite their strong homology, PS1 and PS2 could play different roles in AD.
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Affiliation(s)
- Roberto Rivabene
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena, 299 00161 Rome, Italy
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18
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Wang CY, Xie JW, Wang T, Xu Y, Cai JH, Wang X, Zhao BL, An L, Wang ZY. Hypoxia-triggered m-calpain activation evokes endoplasmic reticulum stress and neuropathogenesis in a transgenic mouse model of Alzheimer's disease. CNS Neurosci Ther 2013; 19:820-33. [PMID: 23889979 DOI: 10.1111/cns.12151] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 05/25/2013] [Accepted: 06/16/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Previous studies have demonstrated that endoplasmic reticulum (ER) stress is activated in Alzheimer's disease (AD) brains. ER stress-triggered unfolded protein response (UPR) leads to tau phosphorylation and neuronal death. AIMS In this study, we tested the hypothesis that hypoxia-induced m-calpain activation is involved in ER stress-mediated AD pathogenesis. METHOD We employed a hypoxic exposure in APP/PS1 transgenic mice and SH-SY5Y cells overexpressing human Swedish mutation APP (APPswe). RESULTS We observed that hypoxia impaired spatial learning and memory in the APP/PS1 mouse. In the transgenic mouse brain, hypoxia increased the UPR, upregulated apoptotic signaling, enhanced the activation of calpain and glycogen synthase kinase-3β (GSK3β), and increased tau hyperphosphorylation and β-amyloid deposition. In APPswe cells, m-calpain silencing reduced hypoxia-induced cellular dysfunction and resulted in suppression of GSK3β activation, ER stress and tau hyperphosphorylation reduction as well as caspase pathway suppression. CONCLUSION These findings demonstrate that hypoxia-induced abnormal calpain activation may increase ER stress-induced apoptosis in AD pathogenesis. In contrast, a reduction in the expression of the m-calpain isoform reduces ER stress-linked apoptosis that is triggered by hypoxia. These findings suggest that hypoxia-triggered m-calpain activation is involved in ER stress-mediated AD pathogenesis. m-calpain is a potential target for AD therapeutics.
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Affiliation(s)
- Chun-Yan Wang
- Department of Pathophysiology, Key Laboratory of Medical Cell Biology of Ministry of Education of China, China Medical University, Shenyang, China; Medical Research Laboratory, Jilin Medical College, Jilin, China
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19
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Crosstalk between Endoplasmic Reticulum Stress and Protein Misfolding in Neurodegenerative Diseases. ACTA ACUST UNITED AC 2013. [DOI: 10.1155/2013/256404] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Under physiological conditions, the endoplasmic reticulum (ER) is a central subcellular compartment for protein quality control in the secretory pathway that prevents protein misfolding and aggregation. Instrumental in protein quality control in the ER is the unfolded protein response (UPR), which is activated upon ER stress to reestablish homeostasis through a sophisticated transcriptionally and translationally regulated signaling network. However, this response can lead to apoptosis if the stress cannot be alleviated. The presence of abnormal protein aggregates containing specific misfolded proteins is recognized as the basis of numerous human conformational disorders, including neurodegenerative diseases. Here, I will highlight the overwhelming evidence that the presence of specific aberrant proteins in Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), prion diseases, and Amyotrophic Lateral Sclerosis (ALS) is intimately associated with perturbations in the ER protein quality control machinery that become incompetent to restore protein homeostasis and shift adaptive programs toward the induction of apoptotic signaling to eliminate irreversibly damaged neurons. Increasing our understanding about the deadly crosstalk between ER dysfunction and protein misfolding in these neurodegenerative diseases may stimulate the development of novel therapeutic strategies able to support neuronal survival and ameliorate disease progression.
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20
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Cornejo VH, Hetz C. The unfolded protein response in Alzheimer’s disease. Semin Immunopathol 2013; 35:277-92. [DOI: 10.1007/s00281-013-0373-9] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 03/13/2013] [Indexed: 01/05/2023]
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21
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Impairment of proteostasis network in Down syndrome prior to the development of Alzheimer's disease neuropathology: redox proteomics analysis of human brain. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1249-59. [PMID: 23603808 DOI: 10.1016/j.bbadis.2013.04.013] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 03/18/2013] [Accepted: 04/10/2013] [Indexed: 01/06/2023]
Abstract
DS is the most frequent genetic cause of intellectual disability characterized by the anomalous presence of three copies of chromosome 21. One of the peculiar features of DS is the onset of Alzheimer's disease neuropathology after the age of 40years characterized by deposition of senile plaques and neurofibrillary tangles. Growing studies demonstrated that increased oxidative damage, accumulation of unfolded/damaged protein aggregates and dysfunction of intracellular degradative system are key players in neurodegenerative processes. In this study, redox proteomics approach was used to analyze the frontal cortex from DS subjects under the age of 40 compared with age-matched controls, and proteins found to be increasingly carbonylated were identified. Interestingly, our results showed that oxidative damage targets specifically different components of the intracellular quality control system such as GRP78, UCH-L1, V0-ATPase, cathepsin D and GFAP that couples with decreased activity of the proteasome and autophagosome formation observed. We also reported a slight but consistent increase of Aβ 1-42 SDS- and PBS-soluble form and tau phosphorylation in DS versus CTR. We suggest that disturbance in the proteostasis network could contribute to the accumulation of protein aggregates, such as amyloid deposits and NFTs, which occur very early in DS. It is likely that a sub-optimal functioning of degradative systems occur in DS neurons, which in turn provide the basis for further accumulation of toxic protein aggregates. The results of this study suggest that oxidation of protein members of the proteostatis network is an early event in DS and might contribute to neurodegenerative phenomena.
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22
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Nijholt DAT, Nölle A, van Haastert ES, Edelijn H, Toonen RF, Hoozemans JJM, Scheper W. Unfolded protein response activates glycogen synthase kinase-3 via selective lysosomal degradation. Neurobiol Aging 2013; 34:1759-71. [PMID: 23415837 DOI: 10.1016/j.neurobiolaging.2013.01.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 12/20/2012] [Accepted: 01/12/2013] [Indexed: 01/01/2023]
Abstract
The unfolded protein response (UPR) is a stress response that is activated upon disturbed homeostasis in the endoplasmic reticulum. In Alzheimer's disease, as well as in other tauopathies, the UPR is activated in neurons that contain early tau pathology. A recent genome-wide association study identified genetic variation in a UPR transducer as a risk factor for tauopathy, supporting a functional connection between UPR activation and tau pathology. Here we show that UPR activation increases the activity of the major tau kinase glycogen synthase kinase (GSK)-3 in vitro via a selective removal of inactive GSK-3 phosphorylated at Ser(21/9). We demonstrate that this is mediated by the autophagy/lysosomal pathway. In brain tissue from patients with different tauopathies, lysosomal accumulations of pSer(21/9) GSK-3 are found in neurons with markers for UPR activation. Our data indicate that UPR activation increases the activity of GSK-3 by a novel mechanism, the lysosomal degradation of the inactive pSer(21/9) GSK-3. This may provide a functional explanation for the close association between UPR activation and early tau pathology in neurodegenerative diseases.
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Affiliation(s)
- Diana A T Nijholt
- Department of Genome Analysis, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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23
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De Kimpe L, Bennis A, Zwart R, van Haastert ES, Hoozemans JJM, Scheper W. Disturbed Ca2+ homeostasis increases glutaminyl cyclase expression; connecting two early pathogenic events in Alzheimer's disease in vitro. PLoS One 2012; 7:e44674. [PMID: 22970285 PMCID: PMC3436868 DOI: 10.1371/journal.pone.0044674] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 08/10/2012] [Indexed: 01/22/2023] Open
Abstract
A major neuropathological hallmark of Alzheimer’s disease (AD) is the deposition of aggregated β amyloid (Aβ) peptide in the senile plaques. Aβ is a peptide of 38–43 amino acids and its accumulation and aggregation plays a key role early in the disease. A large fraction of β amyloid is N-terminally truncated rendering a glutamine that can subsequently be cyclized into pyroglutamate (pE). This makes the peptide more resistant to proteases, more prone to aggregation and increases its neurotoxicity. The enzyme glutaminyl cyclase (QC) catalyzes this conversion of glutamine to pE. In brains of AD patients, the expression of QC is increased in the earliest stages of pathology, which may be an important event in the pathogenesis. In this study we aimed to investigate the regulatory mechanism underlying the upregulation of QC expression in AD. Using differentiated SK-N-SH as a neuronal cell model, we found that neither the presence of Aβ peptides nor the unfolded protein response, two early events in AD, leads to increased QC levels. In contrast, we demonstrated increased QC mRNA levels and enzyme activity in response to another pathogenic factor in AD, perturbed intracellular Ca2+ homeostasis. The QC promoter contains a putative binding site for the Ca2+ dependent transcription factors c-fos and c-jun. C-fos and c-jun are induced by the same Ca2+-related stimuli as QC and their upregulation precedes QC expression. We show that in the human brain QC is predominantly expressed by neurons. Interestingly, the Ca2+- dependent regulation of both c-fos and QC is not observed in non-neuronal cells. Our results indicate that perturbed Ca2+ homeostasis results in upregulation of QC selectively in neuronal cells via Ca2+- dependent transcription factors. This suggests that disruption of Ca2+ homeostasis may contribute to the formation of the neurotoxic pE Aβ peptides in Alzheimer’s disease.
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Affiliation(s)
- Line De Kimpe
- Department of Genome Analysis, Academic Medical Center/University of Amsterdam, Amsterdam, The Netherlands
| | - Anna Bennis
- Department of Genome Analysis, Academic Medical Center/University of Amsterdam, Amsterdam, The Netherlands
| | - Rob Zwart
- Department of Genome Analysis, Academic Medical Center/University of Amsterdam, Amsterdam, The Netherlands
| | | | | | - Wiep Scheper
- Department of Genome Analysis, Academic Medical Center/University of Amsterdam, Amsterdam, The Netherlands
- Department of Neurology, Academic Medical Center/University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
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24
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Ferreiro E, Baldeiras I, Ferreira IL, Costa RO, Rego AC, Pereira CF, Oliveira CR. Mitochondrial- and endoplasmic reticulum-associated oxidative stress in Alzheimer's disease: from pathogenesis to biomarkers. Int J Cell Biol 2012; 2012:735206. [PMID: 22701485 PMCID: PMC3373122 DOI: 10.1155/2012/735206] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 04/06/2012] [Indexed: 12/23/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia in the elderly, affecting several million of people worldwide. Pathological changes in the AD brain include the presence of amyloid plaques, neurofibrillary tangles, loss of neurons and synapses, and oxidative damage. These changes strongly associate with mitochondrial dysfunction and stress of the endoplasmic reticulum (ER). Mitochondrial dysfunction is intimately linked to the production of reactive oxygen species (ROS) and mitochondrial-driven apoptosis, which appear to be aggravated in the brain of AD patients. Concomitantly, mitochondria are closely associated with ER, and the deleterious crosstalk between both organelles has been shown to be involved in neuronal degeneration in AD. Stimuli that enhance expression of normal and/or folding-defective proteins activate an adaptive unfolded protein response (UPR) that, if unresolved, can cause apoptotic cell death. ER stress also induces the generation of ROS that, together with mitochondrial ROS and decreased activity of several antioxidant defenses, promotes chronic oxidative stress. In this paper we discuss the critical role of mitochondrial and ER dysfunction in oxidative injury in AD cellular and animal models, as well as in biological fluids from AD patients. Progress in developing peripheral and cerebrospinal fluid biomarkers related to oxidative stress will also be summarized.
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Affiliation(s)
- E. Ferreiro
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal 3004-517, Coimbra, Portugal
| | - I. Baldeiras
- Faculty of Medicine, University of Coimbra, Rua Larga 3004-504, Coimbra, Portugal
- University Coimbra Hospital, 3000-075, Coimbra, Portugal
| | - I. L. Ferreira
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal 3004-517, Coimbra, Portugal
| | - R. O. Costa
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal 3004-517, Coimbra, Portugal
| | - A. C. Rego
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal 3004-517, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Rua Larga 3004-504, Coimbra, Portugal
| | - C. F. Pereira
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal 3004-517, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Rua Larga 3004-504, Coimbra, Portugal
| | - C. R. Oliveira
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal 3004-517, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Rua Larga 3004-504, Coimbra, Portugal
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25
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Bernales S, Soto MM, McCullagh E. Unfolded protein stress in the endoplasmic reticulum and mitochondria: a role in neurodegeneration. Front Aging Neurosci 2012; 4:5. [PMID: 22539924 PMCID: PMC3336107 DOI: 10.3389/fnagi.2012.00005] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 04/10/2012] [Indexed: 11/17/2022] Open
Abstract
Protein-folding occurs in several intracellular locations including the endoplasmic reticulum and mitochondria. In normal conditions there is a balance between the levels of unfolded proteins and protein folding machinery. Disruption of homeostasis and an accumulation of unfolded proteins trigger stress responses, or unfolded protein responses (UPR), in these organelles. These pathways signal to increase the folding capacity, inhibit protein import or expression, increase protein degradation, and potentially trigger cell death. Many aging-related neurodegenerative diseases involve the accumulation of misfolded proteins in both the endoplasmic reticulum and mitochondria. The exact participation of the UPRs in the onset of neurodegeneration is unclear, but there is significant evidence for the alteration of these pathways in the endoplasmic reticulum and mitochondria. Here we will discuss the involvement of endoplasmic reticulum and mitochondrial stress and the possible contributions of the UPR in these organelles to the development of two neurodegenerative diseases, Parkinson's disease (PD) and Alzheimer's disease (AD).
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26
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Kumar P, Pradhan K, Karunya R, Ambasta RK, Querfurth HW. Cross-functional E3 ligases Parkin and C-terminus Hsp70-interacting protein in neurodegenerative disorders. J Neurochem 2011; 120:350-70. [DOI: 10.1111/j.1471-4159.2011.07588.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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27
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Wiley JC, Pettan-Brewer C, Ladiges WC. Phenylbutyric acid reduces amyloid plaques and rescues cognitive behavior in AD transgenic mice. Aging Cell 2011; 10:418-28. [PMID: 21272191 DOI: 10.1111/j.1474-9726.2011.00680.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Trafficking through the secretory pathway is known to regulate the maturation of the APP-cleaving secretases and APP proteolysis. The coupling of stress signaling and pathological deterioration of the brain in Alzheimer's disease (AD) supports a mechanistic connection between endoplasmic reticulum (ER) stress and neurodegeneration. Consequently, small molecular chaperones, which promote protein folding and minimize ER stress, might be effective in delaying or attenuating the deleterious progression of AD. We tested this hypothesis by treating APPswePS1delta9 AD transgenic mice with the molecular chaperone phenylbutyric acid (PBA) for 14 months at a dose of 1 mg PBA g(-1) of body weight in the drinking water. Phenylbutyric acid treatment increased secretase-mediated APP cleavage, but was not associated with any increase in amyloid biosynthesis. The PBA-treated AD transgenic mice had significantly decreased incidence and size of amyloid plaques throughout the cortex and hippocampus. There was no change in total amyloid levels suggesting that PBA modifies amyloid aggregation or pathogenesis independently of biogenesis. The decrease in amyloid plaques was paralleled by increased memory retention, as PBA treatment facilitated cognitive performance in a spatial memory task in both wild-type and AD transgenic mice. The molecular mechanism underlying the cognitive facilitation of PBA is not clear; however, increased levels of both metabotropic and ionotropic glutamate receptors, as well as ADAM10 and TACE, were observed in the cortex and hippocampus of PBA-treated mice. The data suggest that PBA ameliorates the cognitive and pathological features of AD and supports the investigation of PBA as a therapeutic for AD.
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Affiliation(s)
- Jesse C Wiley
- Department of Comparative Medicine, University of Washington School of Medicine, Seattle, USA
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Matus S, Glimcher LH, Hetz C. Protein folding stress in neurodegenerative diseases: a glimpse into the ER. Curr Opin Cell Biol 2011; 23:239-52. [PMID: 21288706 DOI: 10.1016/j.ceb.2011.01.003] [Citation(s) in RCA: 177] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 01/05/2011] [Accepted: 01/11/2011] [Indexed: 01/19/2023]
Abstract
Several neurodegenerative diseases share common neuropathology, primarily featuring the presence in the brain of abnormal protein inclusions containing specific misfolded proteins. Recent evidence indicates that alteration in organelle function is a common pathological feature of protein misfolding disorders, highlighting perturbations in the homeostasis of the endoplasmic reticulum (ER). Signs of ER stress have been detected in most experimental models of neurological disorders and more recently in brain samples from human patients with neurodegenerative disease. To cope with ER stress, cells activate an integrated signaling response termed the unfolded protein response (UPR), which aims to reestablish homeostasis in part through regulation of genes involved in protein folding, quality control and degradation pathways. Here we discuss the particular mechanisms currently proposed to be involved in the generation of protein folding stress in different neurodegenerative conditions and speculate about possible therapeutic interventions.
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Affiliation(s)
- Soledad Matus
- Center for Molecular Studies of Cell, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
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29
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Loewen CA, Feany MB. The unfolded protein response protects from tau neurotoxicity in vivo. PLoS One 2010; 5. [PMID: 20927324 PMCID: PMC2947516 DOI: 10.1371/journal.pone.0013084] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2010] [Accepted: 09/09/2010] [Indexed: 02/06/2023] Open
Abstract
The unfolded protein response is a critical system by which the cell handles excess misfolded protein in the secretory pathway. The role of the system in modulating the effects of aggregation prone cytosolic proteins has received less attention. We use genetic reporters to demonstrate activation of the unfolded protein response in a transgenic Drosophila model of Alzheimer's disease and related tauopathies. We then use loss of function genetic reagents to support a role for the unfolded protein response in protecting from tau neurotoxicity. Our findings suggest that the unfolded protein response can ameliorate the toxicity of tau in vivo.
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Affiliation(s)
- Carin A Loewen
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
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Activation of eukaryotic initiation factor-2 α-kinases in okadaic acid-treated neurons. Neuroscience 2010; 169:1831-9. [PMID: 20600673 DOI: 10.1016/j.neuroscience.2010.06.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Revised: 05/17/2010] [Accepted: 06/10/2010] [Indexed: 01/19/2023]
Abstract
Phosphorylation of eukaryotic initiation factor-2 alpha (eIF2 alpha) is increased in Alzheimer's disease (AD) and this protein can be phosphorylated by several kinases, including double-stranded RNA-dependent protein kinase (PKR), PKR-like endoplasmic reticulum kinase (PERK), amino acids-regulated eIF2 alpha kinase (GCN2) and heme-regulated eIF2 alpha kinase (HRI). PKR and PERK especially are activated in the AD brain, and GCN2 is reported to increase presenilin-1 (PS1) activity. Okadaic acid (OA), a protein phosphatase-2A (PP2A) inhibitor, is known to increase tau phosphorylation, beta-amyloid (A beta) deposition and neuronal death, which are the pathological characteristics of AD. Here, we show that the phosphorylation of eIF2 alpha is increased and its kinases, PKR, PERK and GCN2 are activated in rat neurons by OA. Activating transcription factor (ATF4) which induces apoptosis in response to eIF2 alpha phosphorylation was increased and translocated to nuclei in OA-treated neurons. These results suggest that the successive events of activation of eIF2 alpha kinases and eIF2 alpha phosphorylation leading to ATF4 nuclear translocation may contribute to neuronal death. However, PKR inhibitors did not reduce eIF2 alpha phosphorylation or neuronal toxicity despite inhibiting PKR activity. These results suggest that PKR might not be the most responsible kinase for eIF2 alpha phosphorylation or cell death in PP2A-inhibited conditions such as AD.
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31
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Rosen KM, Moussa CEH, Lee HK, Kumar P, Kitada T, Qin G, Fu Q, Querfurth HW. Parkin reverses intracellular beta-amyloid accumulation and its negative effects on proteasome function. J Neurosci Res 2010; 88:167-78. [PMID: 19610108 DOI: 10.1002/jnr.22178] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The significance of intracellular beta-amyloid (Abeta(42)) accumulation is increasingly recognized in Alzheimer's disease (AD) pathogenesis. Abeta removal mechanisms that have attracted attention include IDE/neprilysin degradation and antibody-mediated uptake by immune cells. However, the role of the ubiquitin-proteasome system (UPS) in the disposal of cellular Abeta has not been fully explored. The E3 ubiquitin ligase Parkin targets several proteins for UPS degradation, and Parkin mutations are the major cause of autosomal recessive Parkinson's disease. We tested whether Parkin has cross-function to target misfolded proteins in AD for proteasome-dependent clearance in SH-SY5Y and primary neuronal cells. Wild-type Parkin greatly decreased steady-state levels of intracellular Abeta(42), an action abrogated by proteasome inhibitors. Intracellular Abeta(42) accumulation decreased cell viability and proteasome activity. Accordingly, Parkin reversed both effects. Changes in mitochondrial ATP production from Abeta or Parkin did not account for their effects on the proteasome. Parkin knock-down led to accumulation of Abeta. In AD brain, Parkin was found to interact with Abeta and its levels were reduced. Thus, Parkin is cytoprotective, partially by increasing the removal of cellular Abeta through a proteasome-dependent pathway.
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Affiliation(s)
- Kenneth M Rosen
- Department of Neurology, Tufts University School of Medicine, Boston, Massachusetts, USA
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Hoozemans JJM, van Haastert ES, Nijholt DAT, Rozemuller AJM, Eikelenboom P, Scheper W. The unfolded protein response is activated in pretangle neurons in Alzheimer's disease hippocampus. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 174:1241-51. [PMID: 19264902 DOI: 10.2353/ajpath.2009.080814] [Citation(s) in RCA: 455] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Accumulation of misfolded proteins in the endoplasmic reticulum triggers a cellular stress response called the unfolded protein response (UPR) that protects the cell against the toxic buildup of misfolded proteins. Previously, we reported that UPR activation is increased in Alzheimer's disease (AD) patients. How the UPR relates to the pathological hallmarks of AD is still elusive. In the present study, the involvement of UPR activation in neurofibrillary degeneration in AD was investigated. Immunoreactivity for the phosphorylated UPR activation markers pancreatic ER kinase (pPERK), eukaryotic initiation factor 2alpha, and inositol-requiring enzyme 1alpha was observed in hippocampal neurons associated with granulovacuolar degeneration. The percentage of pPERK-immunoreactive neurons was increased in AD cases compared with nondemented control cases and with the Braak stage for neurofibrillary changes. Although absent from neurofibrillary tangles, pPERK immunoreactivity was most abundant in neurons with diffuse localization of phosphorylated tau protein. Additional analyses showed that pPERK immunoreactivity was associated with ubiquitin and the ubiquitin binding protein p62. A strong co-occurrence of immunoreactivity for both pPERK and glycogen synthase kinase 3beta in neurons was also observed. Together, these data indicate that UPR activation in AD neurons occurs at an early stage of neurofibrillary degeneration and suggest that the prolonged activation of the UPR is involved in both tau phosphorylation and neurodegeneration in AD pathogenesis.
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Affiliation(s)
- Jeroen J M Hoozemans
- VU University Medical Center, Department of Pathology, P.O. Box 7057, 1007 MB Amsterdam, The Netherlands.
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