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Wang T, Jia H. The Sigma Receptors in Alzheimer's Disease: New Potential Targets for Diagnosis and Therapy. Int J Mol Sci 2023; 24:12025. [PMID: 37569401 PMCID: PMC10418732 DOI: 10.3390/ijms241512025] [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: 06/16/2023] [Revised: 07/14/2023] [Accepted: 07/16/2023] [Indexed: 08/13/2023] Open
Abstract
Sigma (σ) receptors are a class of unique proteins with two subtypes: the sigma-1 (σ1) receptor which is situated at the mitochondria-associated endoplasmic reticulum (ER) membrane (MAM), and the sigma-2 (σ2) receptor, located in the ER-resident membrane. Increasing evidence indicates the involvement of both σ1 and σ2 receptors in the pathogenesis of Alzheimer's disease (AD), and thus these receptors represent two potentially effective biomarkers for emerging AD therapies. The availability of optimal radioligands for positron emission tomography (PET) neuroimaging of the σ1 and σ2 receptors in humans will provide tools to monitor AD progression and treatment outcomes. In this review, we first summarize the significance of both receptors in the pathophysiology of AD and highlight AD therapeutic strategies related to the σ1 and σ2 receptors. We then survey the potential PET radioligands, with an emphasis on the requirements of optimal radioligands for imaging the σ1 or σ2 receptors in humans. Finally, we discuss current challenges in the development of PET radioligands for the σ1 or σ2 receptors, and the opportunities for neuroimaging to elucidate the σ1 and σ2 receptors as novel biomarkers for early AD diagnosis, and for monitoring of disease progression and AD drug efficacy.
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Affiliation(s)
- Tao Wang
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China;
- Department of Nuclear Medicine, Xinqiao Hospital, Army Medical University, Chongqing 400037, China
| | - Hongmei Jia
- Key Laboratory of Radiopharmaceuticals (Beijing Normal University), Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China;
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Nan J, Li J, Lin Y, Saif Ur Rahman M, Li Z, Zhu L. The interplay between mitochondria and store-operated Ca 2+ entry: Emerging insights into cardiac diseases. J Cell Mol Med 2021; 25:9496-9512. [PMID: 34564947 PMCID: PMC8505841 DOI: 10.1111/jcmm.16941] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/20/2021] [Accepted: 09/08/2021] [Indexed: 12/14/2022] Open
Abstract
Store‐operated Ca2+ entry (SOCE) machinery, including Orai channels, TRPCs, and STIM1, is key to cellular calcium homeostasis. The following characteristics of mitochondria are involved in the physiological and pathological regulation of cells: mitochondria mediate calcium uptake through calcium uniporters; mitochondria are regulated by mitochondrial dynamic related proteins (OPA1, MFN1/2, and DRP1) and form mitochondrial networks through continuous fission and fusion; mitochondria supply NADH to the electron transport chain through the Krebs cycle to produce ATP; under stress, mitochondria will produce excessive reactive oxygen species to regulate mitochondria‐endoplasmic reticulum interactions and the related signalling pathways. Both SOCE and mitochondria play critical roles in mediating cardiac hypertrophy, diabetic cardiomyopathy, and cardiac ischaemia‐reperfusion injury. All the mitochondrial characteristics mentioned above are determinants of SOCE activity, and vice versa. Ca2+ signalling dictates the reciprocal regulation between mitochondria and SOCE under the specific pathological conditions of cardiomyocytes. The coupling of mitochondria and SOCE is essential for various pathophysiological processes in the heart. Herein, we review the research focussing on the reciprocal regulation between mitochondria and SOCE and provide potential interplay patterns in cardiac diseases.
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Affiliation(s)
- Jinliang Nan
- Provincial Key Cardiovascular Research Laboratory, Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang Province, Hangzhou, China
| | - Jiamin Li
- Provincial Key Cardiovascular Research Laboratory, Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang Province, Hangzhou, China
| | - Yinuo Lin
- Wenzhou Municipal Key Cardiovascular Research Laboratory, Department of Cardiology, The First Affiliated Hospital, Wenzhou Medical University, Zhejiang Province, Wenzhou, China
| | - Muhammad Saif Ur Rahman
- Zhejiang University-University of Edinburgh Biomedical Institute, Haining, Zhejiang, China.,Clinical Research Center, The Second Affiliated Hospital Zhejiang University School of Medicine, Hangzhou, China
| | - Zhengzheng Li
- Department of Neurology, Research Institute of Experimental Neurobiology, The First Affiliated Hospital, Wenzhou Medical University, Zhejiang Province, Wenzhou, China
| | - Lingjun Zhu
- Provincial Key Cardiovascular Research Laboratory, Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang Province, Hangzhou, China
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Yang S, Wang D, Cao X, Zhang X, Yuan X, Yang T, Mi Y. Store operated calcium channels are associated with diabetic cystopathy in streptozotocin‑induced diabetic rats. Mol Med Rep 2018. [PMID: 29532875 PMCID: PMC5928646 DOI: 10.3892/mmr.2018.8723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Store operated calcium channels (SOCCs) have been suggested to play a critical role in many diabetic complications. Diabetic cystopathy (DCP) is common in patients with diabetes, but the role of SOCCs in DCP is still unclear. The aim of the present study was to investigate the role of SOCCs in DCP with streptozocin (STZ)-induced diabetic rats. Specifically, the authors investigated whether SOCCs were altered in streptozocin (STZ)-induced diabetic rats and, if so, how this may contribute to the contraction of bladder detrusor strips and the intracellular Ca2+ concentration of bladder smooth muscle cells in diabetic rats. Cyclopiazonic acid (CPA, 10 µM) and SKF-96365 (10 µM) were used to activate and inhibit SOCCs respectively, to research the effects of SOCCs on the contraction of the bladder detrusor strips in normal and STZ-induced diabetic rats at the 4th, 8th and 12th week after the diabetic rat model was established. The changes of intracellular Ca2+ were also evaluated under confocal microscopy with pretreated Fluo-4AM. In addition, the expressions of Orai1 and STIM1 were detected by reverse transcription-quantitative polymerase chain reaction and western blotting at different time points. According to the results, the contractive frequency of diabetic bladder muscle strips was higher than that of controls in the 4th and 8th week. The increased fluorescence intensity was detected after using CPA and SKF-96365 in diabetic groups. The expressions of Orai1 and STIM1 changed in a time-dependent manner.
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Affiliation(s)
- Sen Yang
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Dongwen Wang
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Xiaoming Cao
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Xuhui Zhang
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Xiaobin Yuan
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Tiancheng Yang
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
| | - Yang Mi
- First College of Clinical Medicine, First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, P.R. China
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Wei YP, Ye JW, Wang X, Zhu LP, Hu QH, Wang Q, Ke D, Tian Q, Wang JZ. Tau-Induced Ca 2+/Calmodulin-Dependent Protein Kinase-IV Activation Aggravates Nuclear Tau Hyperphosphorylation. Neurosci Bull 2017. [PMID: 28646348 DOI: 10.1007/s12264-017-0148-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Hyperphosphorylated tau is the major protein component of neurofibrillary tangles in the brains of patients with Alzheimer's disease (AD). However, the mechanism underlying tau hyperphosphorylation is not fully understood. Here, we demonstrated that exogenously expressed wild-type human tau40 was detectable in the phosphorylated form at multiple AD-associated sites in cytoplasmic and nuclear fractions from HEK293 cells. Among these sites, tau phosphorylated at Thr205 and Ser214 was almost exclusively found in the nuclear fraction at the conditions used in the present study. With the intracellular tau accumulation, the Ca2+ concentration was significantly increased in both cytoplasmic and nuclear fractions. Further studies using site-specific mutagenesis and pharmacological treatment demonstrated that phosphorylation of tau at Thr205 increased nuclear Ca2+ concentration with a simultaneous increase in the phosphorylation of Ca2+/calmodulin-dependent protein kinase IV (CaMKIV) at Ser196. On the other hand, phosphorylation of tau at Ser214 did not significantly change the nuclear Ca2+/CaMKIV signaling. Finally, expressing calmodulin-binding protein-4 that disrupts formation of the Ca2+/calmodulin complex abolished the okadaic acid-induced tau hyperphosphorylation in the nuclear fraction. We conclude that the intracellular accumulation of phosphorylated tau, as detected in the brains of AD patients, can trigger nuclear Ca2+/CaMKIV signaling, which in turn aggravates tau hyperphosphorylation. Our findings provide new insights for tauopathies: hyperphosphorylation of intracellular tau and an increased Ca2+ concentration may induce a self-perpetuating harmful loop to promote neurodegeneration.
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Affiliation(s)
- Yu-Ping Wei
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jin-Wang Ye
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiong Wang
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Li-Ping Zhu
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qing-Hua Hu
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qun Wang
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Dan Ke
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qing Tian
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China. .,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Jian-Zhi Wang
- Pathophysiology Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China. .,Key Laboratory of Ministry of Education for Neurological Disorders and Hubei Provincial Key Laboratory for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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From Stores to Sinks: Structural Mechanisms of Cytosolic Calcium Regulation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 981:215-251. [PMID: 29594864 DOI: 10.1007/978-3-319-55858-5_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
All eukaryotic cells have adapted the use of the calcium ion (Ca2+) as a universal signaling element through the evolution of a toolkit of Ca2+ sensor, buffer and effector proteins. Among these toolkit components, integral and peripheral proteins decorate biomembranes and coordinate the movement of Ca2+ between compartments, sense these concentration changes and elicit physiological signals. These changes in compartmentalized Ca2+ levels are not mutually exclusive as signals propagate between compartments. For example, agonist induced surface receptor stimulation can lead to transient increases in cytosolic Ca2+ sourced from endoplasmic reticulum (ER) stores; the decrease in ER luminal Ca2+ can subsequently signal the opening surface channels which permit the movement of Ca2+ from the extracellular space to the cytosol. Remarkably, the minuscule compartments of mitochondria can function as significant cytosolic Ca2+ sinks by taking up Ca2+ in a coordinated manner. In non-excitable cells, inositol 1,4,5 trisphosphate receptors (IP3Rs) on the ER respond to surface receptor stimulation; stromal interaction molecules (STIMs) sense the ER luminal Ca2+ depletion and activate surface Orai1 channels; surface Orai1 channels selectively permit the movement of Ca2+ from the extracellular space to the cytosol; uptake of Ca2+ into the matrix through the mitochondrial Ca2+ uniporter (MCU) further shapes the cytosolic Ca2+ levels. Recent structural elucidations of these key Ca2+ toolkit components have improved our understanding of how they function to orchestrate precise cytosolic Ca2+ levels for specific physiological responses. This chapter reviews the atomic-resolution structures of IP3R, STIM1, Orai1 and MCU elucidated by X-ray crystallography, electron microscopy and NMR and discusses the mechanisms underlying their biological functions in their respective compartments within the cell.
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Sánchez JA, Alfonso A, Thomas OP, Botana LM. Autumnalamide targeted proteins of the immunophilin family. Immunobiology 2016; 222:241-250. [PMID: 27720433 DOI: 10.1016/j.imbio.2016.09.016] [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] [Received: 03/01/2016] [Revised: 09/19/2016] [Accepted: 09/26/2016] [Indexed: 11/25/2022]
Abstract
Previous works with autumnalamide reported that Store Operated Calcium (SOC) channels were blocked through mitochondrial modulation. In the present paper we studied the effect of autumnalamide on ionomycin Ca2+ fluxes. Thus, autumnalamide did not modify ionomycin-sensitive intracellular pools while the ionomycin-induced Ca2+ influx was blocked with similar potency whether the incubation was done before or after ionomycin-sensitive pools depletion. Nevertheless, autumnalamide was not able to inhibit ionomycin-induced Ca2+ influx once the membrane channels were activated. Moreover, the compound efficiently inhibited flufenamic acid (FFA) Ca2+ release induced in this organelle but no the next influx. Since in previous work the effect of autumnalamide was inhibited by cyclosporine A (CsA), structures that target this drug were studied. Therefore, the affinity of autumnalamide for cyclophilin D (Cyp D) was examined. The KD obtained for Cyp D- autumnalamide was 1.51±1.399. Moreover, the KD for Cyp A- autumnalamide was calculated. The peptide had a similar order of Cyp A binding affinity than CsA (8.08±1.23 and 6.85±1.1μM respectively). After testing autumnalamide-binding capacity for Cyp A, the activity of this compound on Cyp A pathway was tested. Thus, the effect on interleukin (IL)-2 release on activated T-lymphocytes was checked. Autumnalamide was able to reduce IL-2 levels near to T cells in resting conditions. Next, the effect over calcineurin and NFATc1 was also evaluated. While CsA inhibits both calcineurin and NFATc1, autumnalamide did not produce any effect. From these results we can conclude that, autumnalamide targeted mitochondrion and prevent T-cells from IL-2 production through the modulation of SOC Ca2+ channels.
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Affiliation(s)
- Jon Andoni Sánchez
- Departamento de Farmacología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain.
| | - Amparo Alfonso
- Departamento de Farmacología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain.
| | - Olivier P Thomas
- Geoazur, UMR Université Nice Sophia Antipolis-CNRS-IRD-OCA, 250 rue Albert Einstein, 06560, Valbonne, France; Marine Biodiscovery, School of Chemistry, National University of Ireland Galway, University Road, Galway, Ireland.
| | - Luís M Botana
- Departamento de Farmacología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain.
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Naia L, Ferreira IL, Ferreiro E, Rego AC. Mitochondrial Ca 2+ handling in Huntington's and Alzheimer's diseases - Role of ER-mitochondria crosstalk. Biochem Biophys Res Commun 2016; 483:1069-1077. [PMID: 27485547 DOI: 10.1016/j.bbrc.2016.07.122] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 07/26/2016] [Accepted: 07/29/2016] [Indexed: 10/21/2022]
Abstract
Mitochondria play a relevant role in Ca2+ buffering, governing energy metabolism and neuronal function. Huntington's disease (HD) and Alzheimer's disease (AD) are two neurodegenerative disorders that, although clinically distinct, share pathological features linked to selective brain damage. These include mitochondrial dysfunction, intracellular Ca2+ deregulation and mitochondrial Ca2+ handling deficits. Both diseases are associated with misfolding and aggregation of specific proteins that physically interact with mitochondria and interfere with endoplasmic reticulum (ER)/mitochondria-contact sites. Cumulating evidences indicate that impairment of mitochondrial Ca2+ homeostasis underlies the susceptibility to selective neuronal death observed in HD and AD; however data obtained with different models and experimental approaches are not always consistent. In this review, we explore the recent literature on deregulation of mitochondrial Ca2+ handling underlying the interplay between mitochondria and ER in HD and AD-associated neurodegeneration.
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Affiliation(s)
- Luana Naia
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Ildete Luísa Ferreira
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; IIIUC-Institute for Interdisciplinary Research, University of Coimbra (IIIUC), Polo II, Coimbra, Portugal
| | - Elisabete Ferreiro
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; IIIUC-Institute for Interdisciplinary Research, University of Coimbra (IIIUC), Polo II, Coimbra, Portugal
| | - A Cristina Rego
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
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Pallo SP, Johnson GVW. Tau facilitates Aβ-induced loss of mitochondrial membrane potential independent of cytosolic calcium fluxes in mouse cortical neurons. Neurosci Lett 2015; 597:32-7. [PMID: 25888814 DOI: 10.1016/j.neulet.2015.04.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 04/09/2015] [Accepted: 04/12/2015] [Indexed: 11/16/2022]
Abstract
Alzheimer's disease (AD) is defined by presence of two pathological hallmarks, the intraneuronal neurofibrillary tangle (NFT) formed by abnormally processed tau, and the extracellular amyloid plaques formed primarily by the amyloid beta peptide (Aβ). In AD it is likely that these two proteins act in concert to impair neuronal function, and there is evidence to suggest that one of the key targets on which they converge is the mitochondria. For example, overexpression of a pathologic form of tau in rat primary cortical neurons exacerbates Aβ-induced mitochondrial membrane potential (ΔΨm) loss due to impairment of the calcium (Ca(2+)) buffering capability of mitochondria. However the role of physiological levels of tau in mediating Aβ-induced mitochondrial dysfunction was not examined. Therefore in this present study we used primary neurons from wild type (WT) and tau knockout (tau(-/-)) mice to investigate whether endogenous tau facilitates Aβ-induced ΔΨm loss and alterations in cytosolic calcium (Ca(2+)cyt). Knocking out tau significantly protected mouse primary cortical neurons from loss of ΔΨm caused by low concentrations of Aβ42, which supports our previous findings. However, the absence of tau resulted in significantly greater increases in Ca(2+)cyt in response to Aβ treatment when compared to those observed in WT mouse primary cortical neurons. This unexpected outcome may be explained by findings that suggest tau(-/-) neurons display certain phenotypic abnormalities associated with alterations in Ca(2+)cyt. Overall, data indicate that tau facilitates Aβ-induced mitochondrial dysfunction and this effect is independent of Aβ-induced alterations in Ca(2+)cyt.(1).
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Affiliation(s)
- Susanne P Pallo
- Department of Anesthesiology, University of Rochester Medical Center, Rochester, NY, USA
| | - Gail V W Johnson
- Department of Anesthesiology, University of Rochester Medical Center, Rochester, NY, USA.
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De Caluwé J, Dupont G. The progression towards Alzheimer's disease described as a bistable switch arising from the positive loop between amyloids and Ca(2+). J Theor Biol 2013; 331:12-8. [PMID: 23614875 DOI: 10.1016/j.jtbi.2013.04.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 04/11/2013] [Accepted: 04/13/2013] [Indexed: 11/28/2022]
Abstract
Alzheimer's disease is a progressive neurodegenerative disorder affecting millions of people. It is characterized by the slow deposition of cerebral amyloid-β peptides in the brain and by dysregulations in neuronal Ca(2+) homeostasis. Numerous experimental studies have revealed the existence of a feed-forward loop wherein amyloids-β disturb neuronal Ca(2+) levels, which in turn affect the production of amyloids. Here, we formalize this positive loop in a minimal, qualitative model and show that it exhibits bistability. Thus, a stable steady state characterized by low levels of Ca(2+) and amyloids, corresponding to a healthy situation, coexists with another 'pathological state' where the levels of both compounds are high. The onset of the disease corresponds to the switch from the lower steady state to the higher one induced by a large-enough perturbation in either the metabolism of amyloids or the homeostasis of intracellular Ca(2+). Numerical simulations of the model reproduce a variety of experimental observations about the disease, as its irreversible character, the threshold-like transition to a severe pathology after the slow accumulation of symptoms, the effect of presenilins, the so-called 'prion-like' autocatalytic behaviour of amyloids and the inherent random character of the apparition of the disease that is well known for the sporadic form. The model thus provides a conceptual framework that could be useful when developing therapeutic protocols to slow down the progression of Alzheimer's disease.
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Affiliation(s)
- Joëlle De Caluwé
- Unité de Chronobiologie Théorique, Université Libre de Bruxelles ULB, Faculté des Sciences, Brussels, Belgium
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Amyloid precursor protein-mediated modulation of capacitive calcium entry. CHINESE SCIENCE BULLETIN-CHINESE 2012. [DOI: 10.1007/s11434-012-5526-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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