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Holper S, Loveland P, Churilov L, Italiano D, Watson R, Yassi N. Blood Astrocyte Biomarkers in Alzheimer Disease: A Systematic Review and Meta-Analysis. Neurology 2024; 103:e209537. [PMID: 38986050 PMCID: PMC11314950 DOI: 10.1212/wnl.0000000000209537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 04/05/2024] [Indexed: 07/12/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Neuroinflammation, particularly early astrocyte reactivity, is a significant driver of Alzheimer disease (AD) pathogenesis. It is unclear how the levels of astrocyte biomarkers change in patients across the AD continuum and which best reflect AD-related change. We performed a systematic review and meta-analysis of 3 blood astrocyte biomarkers (glial fibrillary acidic protein [GFAP], chitinase-3-like protein 1 [YKL-40], and S100B) in patients clinically diagnosed with AD. METHODS MEDLINE and Web of Science were searched on March 23, 2023, without restrictions on language, time, or study design, for studies reporting blood levels of the astrocyte biomarkers GFAP, YKL-40, or S100B in patients on the AD continuum (including those with mild cognitive impairment [MCI] and dementia) and a cognitively unimpaired (CU) control population. AD diagnosis was based on established diagnostic criteria and/or comprehensive multidisciplinary clinical consensus. Studies reporting indirect biomarker measures (e.g., levels of biomarker autoantibodies) were excluded. Risk of bias assessment was performed using the revised Quality Assessment of Diagnostic Accuracy Studies tool. Pooled effect sizes were determined using the Hedge g method with a random-effects model. The review was prospectively registered on PROSPERO (registration number CRD42023458305). RESULTS The search identified 1,186 studies; 36 met inclusion criteria (AD continuum n = 3,366, CU n = 4,115). No study was assessed to have a high risk of bias. Compared with CU individuals, patients on the AD continuum had higher GFAP and YKL-40 levels (GFAP effect size 1.15, 95% CI 0.94-1.36, p < 0.0001; YKL-40 effect size 0.38, 95% CI 0.28-0.49, p < 0.0001). Both biomarkers were elevated in more advanced clinical stages of the disease (i.e., in AD dementia compared with MCI due to AD: GFAP effect size 0.48, 95% CI 0.19-0.76, p = 0.0009; YKL-40 effect size 0.34, 95% CI 0.10-0.57, p = 0.0048). No significant differences in blood S100B levels were identified. DISCUSSION We demonstrated significant elevations in blood GFAP and YKL-40 levels in patients on the AD continuum compared with CU individuals. Furthermore, within the AD clinical spectrum, significant elevation correlated with more advanced disease stage. Our findings suggest that both biomarkers reflect AD-related pathology. Our findings are limited by the lack of cultural and linguistic diversity in the study populations meta-analyzed. Future meta-analyses using a biomarker-defined AD population are warranted.
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Affiliation(s)
- Sarah Holper
- From the Population Health and Immunity Division (S.H., P.L., R.W., N.Y.), The Walter and Eliza Hall Institute of Medical Research; Department of Medicine (S.H., P.L., L.C., D.I., R.W., N.Y.), The Royal Melbourne Hospital, and Department of Neurology (N.Y.), Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
| | - Paula Loveland
- From the Population Health and Immunity Division (S.H., P.L., R.W., N.Y.), The Walter and Eliza Hall Institute of Medical Research; Department of Medicine (S.H., P.L., L.C., D.I., R.W., N.Y.), The Royal Melbourne Hospital, and Department of Neurology (N.Y.), Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
| | - Leonid Churilov
- From the Population Health and Immunity Division (S.H., P.L., R.W., N.Y.), The Walter and Eliza Hall Institute of Medical Research; Department of Medicine (S.H., P.L., L.C., D.I., R.W., N.Y.), The Royal Melbourne Hospital, and Department of Neurology (N.Y.), Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
| | - Dominic Italiano
- From the Population Health and Immunity Division (S.H., P.L., R.W., N.Y.), The Walter and Eliza Hall Institute of Medical Research; Department of Medicine (S.H., P.L., L.C., D.I., R.W., N.Y.), The Royal Melbourne Hospital, and Department of Neurology (N.Y.), Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
| | - Rosie Watson
- From the Population Health and Immunity Division (S.H., P.L., R.W., N.Y.), The Walter and Eliza Hall Institute of Medical Research; Department of Medicine (S.H., P.L., L.C., D.I., R.W., N.Y.), The Royal Melbourne Hospital, and Department of Neurology (N.Y.), Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
| | - Nawaf Yassi
- From the Population Health and Immunity Division (S.H., P.L., R.W., N.Y.), The Walter and Eliza Hall Institute of Medical Research; Department of Medicine (S.H., P.L., L.C., D.I., R.W., N.Y.), The Royal Melbourne Hospital, and Department of Neurology (N.Y.), Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
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Del Moro L, Pirovano E, Rota E. Mind the Metabolic Gap: Bridging Migraine and Alzheimer's disease through Brain Insulin Resistance. Aging Dis 2024:AD.2024.0351. [PMID: 38913047 DOI: 10.14336/ad.2024.0351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 06/11/2024] [Indexed: 06/25/2024] Open
Abstract
Brain insulin resistance has recently been described as a metabolic abnormality of brain glucose homeostasis that has been proven to downregulate insulin receptors, both in astrocytes and neurons, triggering a reduction in glucose uptake and glycogen synthesis. This condition may generate a mismatch between brain's energy reserve and expenditure, mainly during high metabolic demand, which could be involved in the chronification of migraine and, in the long run, at least in certain subsets of patients, in the prodromic phase of Alzheimer's disease, along a putative metabolic physiopathological continuum. Indeed, the persistent disruption of glucose homeostasis and energy supply to neurons may eventually impair protein folding, an energy-requiring process, promoting pathological changes in Alzheimer's disease, such as amyloid-β deposition and tau hyperphosphorylation. Hopefully, the "neuroenergetic hypothesis" presented herein will provide further insight on there being a conceivable metabolic bridge between chronic migraine and Alzheimer's disease, elucidating novel potential targets for the prophylactic treatment of both diseases.
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Affiliation(s)
- Lorenzo Del Moro
- Personalized Medicine, Asthma and Allergy, IRCCS Humanitas Research Hospital, Rozzano (MI), Italy
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
| | - Elenamaria Pirovano
- Center for Research in Medical Pharmacology, University of Insubria, Varese, Italy
| | - Eugenia Rota
- Neurology Unit, San Giacomo Hospital, Novi Ligure, ASL AL, Italy
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Sullivan MA, Lane SD, McKenzie ADJ, Ball SR, Sunde M, Neely GG, Moreno CL, Maximova A, Werry EL, Kassiou M. iPSC-derived PSEN2 (N141I) astrocytes and microglia exhibit a primed inflammatory phenotype. J Neuroinflammation 2024; 21:7. [PMID: 38178159 PMCID: PMC10765839 DOI: 10.1186/s12974-023-02951-2] [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: 11/11/2022] [Accepted: 11/07/2023] [Indexed: 01/06/2024] Open
Abstract
BACKGROUND Widescale evidence points to the involvement of glia and immune pathways in the progression of Alzheimer's disease (AD). AD-associated iPSC-derived glial cells show a diverse range of AD-related phenotypic states encompassing cytokine/chemokine release, phagocytosis and morphological profiles, but to date studies are limited to cells derived from PSEN1, APOE and APP mutations or sporadic patients. The aim of the current study was to successfully differentiate iPSC-derived microglia and astrocytes from patients harbouring an AD-causative PSEN2 (N141I) mutation and characterise the inflammatory and morphological profile of these cells. METHODS iPSCs from three healthy control individuals and three familial AD patients harbouring a heterozygous PSEN2 (N141I) mutation were used to derive astrocytes and microglia-like cells and cell identity and morphology were characterised through immunofluorescent microscopy. Cellular characterisation involved the stimulation of these cells by LPS and Aβ42 and analysis of cytokine/chemokine release was conducted through ELISAs and multi-cytokine arrays. The phagocytic capacity of these cells was then indexed by the uptake of fluorescently-labelled fibrillar Aβ42. RESULTS AD-derived astrocytes and microglia-like cells exhibited an atrophied and less complex morphological appearance than healthy controls. AD-derived astrocytes showed increased basal expression of GFAP, S100β and increased secretion and phagocytosis of Aβ42 while AD-derived microglia-like cells showed decreased IL-8 secretion compared to healthy controls. Upon immunological challenge AD-derived astrocytes and microglia-like cells showed exaggerated secretion of the pro-inflammatory IL-6, CXCL1, ICAM-1 and IL-8 from astrocytes and IL-18 and MIF from microglia. CONCLUSION Our study showed, for the first time, the differentiation and characterisation of iPSC-derived astrocytes and microglia-like cells harbouring a PSEN2 (N141I) mutation. PSEN2 (N141I)-mutant astrocytes and microglia-like cells presented with a 'primed' phenotype characterised by reduced morphological complexity, exaggerated pro-inflammatory cytokine secretion and altered Aβ42 production and phagocytosis.
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Affiliation(s)
- Michael A Sullivan
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - Samuel D Lane
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - André D J McKenzie
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - Sarah R Ball
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - Margaret Sunde
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - G Gregory Neely
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Camperdown, Australia
| | - Cesar L Moreno
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Camperdown, Australia
| | - Alexandra Maximova
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia
| | - Eryn L Werry
- School of Medical Sciences, The Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.
- School of Chemistry, The Faculty of Science, The University of Sydney, Camperdown, Australia.
- Central Clinical School, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.
| | - Michael Kassiou
- School of Chemistry, The Faculty of Science, The University of Sydney, Camperdown, Australia.
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Ding S, Wang C, Wang W, Yu H, Chen B, Liu L, Zhang M, Lang Y. Autocrine S100B in astrocytes promotes VEGF-dependent inflammation and oxidative stress and causes impaired neuroprotection. Cell Biol Toxicol 2023; 39:1-25. [PMID: 34792689 DOI: 10.1007/s10565-021-09674-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 10/11/2021] [Indexed: 12/20/2022]
Abstract
Minimal hepatic encephalopathy (MHE) is strongly associated with neuroinflammation. Nevertheless, the underlying mechanism of the induction of inflammatory response in MHE astrocytes remains not fully understood. In the present study, we investigated the effect and mechanism of S100B, a predominant isoform expressed and released from mature astrocytes, on MHE-like neuropathology in the MHE rat model. We discovered that S100B expressions and autocrine were significantly increased in MHE rat brains and MHE rat brain-derived astrocytes. Furthermore, S100B stimulates VEGF expression via the interaction between TLR2 and RAGE in an autocrine manner. S100B-facilitated VEGF autocrine expression further led to a VEGFR2 and COX-2 interaction, which in turn induced the activation of NFƙB, eventually resulting in inflammation and oxidative stress in MHE astrocytes. MHE astrocytes supported impairment of neuronal survival and growth in a co-culture system. To sum up, a comprehensive understanding of the role of S100B-overexpressed MHE astrocyte in MHE pathogenesis may provide insights into the etiology of MHE.
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Affiliation(s)
- Saidan Ding
- Central Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China.
| | - Chengde Wang
- Neurosurgery department, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China
| | - Weikan Wang
- Department of Microbiology, Immunology and Genetics, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA
| | - He Yu
- Central Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China
| | - Baihui Chen
- Central Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China
| | - Leping Liu
- Central Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China
| | - Minxue Zhang
- Central Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China
| | - Yan Lang
- Central Laboratory, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China
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Michetti F, Clementi ME, Di Liddo R, Valeriani F, Ria F, Rende M, Di Sante G, Romano Spica V. The S100B Protein: A Multifaceted Pathogenic Factor More Than a Biomarker. Int J Mol Sci 2023; 24:ijms24119605. [PMID: 37298554 DOI: 10.3390/ijms24119605] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
S100B is a calcium-binding protein mainly concentrated in astrocytes in the nervous system. Its levels in biological fluids are recognized as a reliable biomarker of active neural distress, and more recently, mounting evidence points to S100B as a Damage-Associated Molecular Pattern molecule, which, at high concentration, triggers tissue reactions to damage. S100B levels and/or distribution in the nervous tissue of patients and/or experimental models of different neural disorders, for which the protein is used as a biomarker, are directly related to the progress of the disease. In addition, in experimental models of diseases such as Alzheimer's and Parkinson's diseases, amyotrophic lateral sclerosis, multiple sclerosis, traumatic and vascular acute neural injury, epilepsy, and inflammatory bowel disease, alteration of S100B levels correlates with the occurrence of clinical and/or toxic parameters. In general, overexpression/administration of S100B worsens the clinical presentation, whereas deletion/inactivation of the protein contributes to the amelioration of the symptoms. Thus, the S100B protein may be proposed as a common pathogenic factor in different disorders, sharing different symptoms and etiologies but appearing to share some common pathogenic processes reasonably attributable to neuroinflammation.
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Affiliation(s)
- Fabrizio Michetti
- Department of Neuroscience, Catholic University of the Sacred Heart, 00168 Rome, Italy
- IRCCS San Raffaele Scientific Institute, Università Vita-Salute San Raffaele, 20132 Milan, Italy
- Department of Medicine, LUM University, 70010 Casamassima, Italy
- Genes, Via Venti Settembre 118, 00187 Roma, Italy
| | | | - Rosa Di Liddo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, 35131 Padova, Italy
| | - Federica Valeriani
- Laboratory of Epidemiology and Biotechnologies, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135 Rome, Italy
| | - Francesco Ria
- Department of Translational Medicine and Surgery, Section of General Pathology, Catholic University of the Sacred Heart, 00168 Rome, Italy
| | - Mario Rende
- Department of Medicine and Surgery, Section of Human, Clinical and Forensic Anatomy, University of Perugia, 06132 Perugia, Italy
| | - Gabriele Di Sante
- Department of Medicine and Surgery, Section of Human, Clinical and Forensic Anatomy, University of Perugia, 06132 Perugia, Italy
| | - Vincenzo Romano Spica
- Laboratory of Epidemiology and Biotechnologies, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135 Rome, Italy
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Koronyo Y, Rentsendorj A, Mirzaei N, Regis GC, Sheyn J, Shi H, Barron E, Cook-Wiens G, Rodriguez AR, Medeiros R, Paulo JA, Gupta VB, Kramerov AA, Ljubimov AV, Van Eyk JE, Graham SL, Gupta VK, Ringman JM, Hinton DR, Miller CA, Black KL, Cattaneo A, Meli G, Mirzaei M, Fuchs DT, Koronyo-Hamaoui M. Retinal pathological features and proteome signatures of Alzheimer's disease. Acta Neuropathol 2023; 145:409-438. [PMID: 36773106 PMCID: PMC10020290 DOI: 10.1007/s00401-023-02548-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/12/2023]
Abstract
Alzheimer's disease (AD) pathologies were discovered in the accessible neurosensory retina. However, their exact nature and topographical distribution, particularly in the early stages of functional impairment, and how they relate to disease progression in the brain remain largely unknown. To better understand the pathological features of AD in the retina, we conducted an extensive histopathological and biochemical investigation of postmortem retina and brain tissues from 86 human donors. Quantitative examination of superior and inferior temporal retinas from mild cognitive impairment (MCI) and AD patients compared to those with normal cognition (NC) revealed significant increases in amyloid β-protein (Aβ42) forms and novel intraneuronal Aβ oligomers (AβOi), which were closely associated with exacerbated retinal macrogliosis, microgliosis, and tissue atrophy. These pathologies were unevenly distributed across retinal layers and geometrical areas, with the inner layers and peripheral subregions exhibiting most pronounced accumulations in the MCI and AD versus NC retinas. While microgliosis was increased in the retina of these patients, the proportion of microglial cells engaging in Aβ uptake was reduced. Female AD patients exhibited higher levels of retinal microgliosis than males. Notably, retinal Aβ42, S100 calcium-binding protein B+ macrogliosis, and atrophy correlated with severity of brain Aβ pathology, tauopathy, and atrophy, and most retinal pathologies reflected Braak staging. All retinal biomarkers correlated with the cognitive scores, with retinal Aβ42, far-peripheral AβOi and microgliosis displaying the strongest correlations. Proteomic analysis of AD retinas revealed activation of specific inflammatory and neurodegenerative processes and inhibition of oxidative phosphorylation/mitochondrial, and photoreceptor-related pathways. This study identifies and maps retinopathy in MCI and AD patients, demonstrating the quantitative relationship with brain pathology and cognition, and may lead to reliable retinal biomarkers for noninvasive retinal screening and monitoring of AD.
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Affiliation(s)
- Yosef Koronyo
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Altan Rentsendorj
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Nazanin Mirzaei
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Giovanna C Regis
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Julia Sheyn
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Haoshen Shi
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Ernesto Barron
- Doheny Eye Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Galen Cook-Wiens
- Biostatistics and Bioinformatics Research Center, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Anthony R Rodriguez
- Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Rodrigo Medeiros
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, USA
| | - Veer B Gupta
- School of Medicine, Deakin University, Victoria, Australia
| | - Andrei A Kramerov
- Department of Biomedical Sciences and Eye Program, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alexander V Ljubimov
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
- Department of Biomedical Sciences and Eye Program, Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Departments of Neurology and Biomedical Sciences, Division of Applied Cell Biology and Physiology, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, USA
| | - Jennifer E Van Eyk
- Departments of Neurology and Biomedical Sciences, Division of Applied Cell Biology and Physiology, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, USA
- Barbra Streisand Women's Heart Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Stuart L Graham
- Save Sight Institute, University of Sydney, Sydney, NSW, Australia
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Vivek K Gupta
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - John M Ringman
- Department of Neurology, Keck School of Medicine of USC, Los Angeles, CA, USA
| | - David R Hinton
- Departments of Pathology and Ophthalmology, Keck School of Medicine, USC Roski Eye Institute, University of Southern California, Los Angeles, CA, USA
| | - Carol A Miller
- Department of Pathology Program in Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Keith L Black
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Antonino Cattaneo
- European Brain Research Institute (EBRI), Viale Regina Elena, Rome, Italy
| | - Giovanni Meli
- European Brain Research Institute (EBRI), Viale Regina Elena, Rome, Italy
| | - Mehdi Mirzaei
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Dieu-Trang Fuchs
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA
| | - Maya Koronyo-Hamaoui
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048, USA.
- Departments of Neurology and Biomedical Sciences, Division of Applied Cell Biology and Physiology, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, USA.
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Figueira AJ, Saavedra J, Cardoso I, Gomes CM. S100B chaperone multimers suppress the formation of oligomers during Aβ42 aggregation. Front Neurosci 2023; 17:1162741. [PMID: 37025373 PMCID: PMC10070764 DOI: 10.3389/fnins.2023.1162741] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 03/06/2023] [Indexed: 04/08/2023] Open
Abstract
Extracellular aggregation of the amyloid-β 1-42 (Aβ42) peptide is a major hallmark of Alzheimer's disease (AD), with recent data suggesting that Aβ intermediate oligomers (AβO) are more cytotoxic than mature amyloid fibrils. Understanding how chaperones harness such amyloid oligomers is critical toward establishing the mechanisms underlying regulation of proteostasis in the diseased brain. This includes S100B, an extracellular signaling Ca2+-binding protein which is increased in AD as a response to neuronal damage and whose holdase-type chaperone activity was recently unveiled. Driven by this evidence, we here investigate how different S100B chaperone multimers influence the formation of oligomers during Aβ42 fibrillation. Resorting to kinetic analysis coupled with simulation of AβO influx distributions, we establish that supra-stoichiometric ratios of dimeric S100B-Ca2+ drastically decrease Aβ42 oligomerization rate by 95% and AβO levels by 70% due to preferential inhibition of surface-catalyzed secondary nucleation, with a concomitant redirection of aggregation toward elongation. We also determined that sub-molar ratios of tetrameric apo-S100B decrease Aβ42 oligomerization influx down to 10%, while precluding both secondary nucleation and, more discreetly, fibril elongation. Coincidently, the mechanistic predictions comply with the independent screening of AβO using a combination of the thioflavin-T and X-34 fluorophores. Altogether, our findings illustrate that different S100B multimers act as complementary suppressors of Aβ42 oligomerization and aggregation, further underpinning their potential neuroprotective role in AD.
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Affiliation(s)
- António J. Figueira
- BioISI–Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Joana Saavedra
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC–Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- ICBAS–Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Isabel Cardoso
- i3S–Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC–Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- ICBAS–Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Cláudio M. Gomes
- BioISI–Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- *Correspondence: Cláudio M. Gomes,
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8
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Figueira AJ, Moreira GG, Saavedra J, Cardoso I, Gomes CM. Tetramerization of the S100B Chaperone Spawns a Ca 2+ Independent Regulatory Surface that Enhances Anti-aggregation Activity and Client Specificity. J Mol Biol 2022; 434:167791. [PMID: 35970403 DOI: 10.1016/j.jmb.2022.167791] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 10/15/2022]
Abstract
Alzheimer's disease (AD) hallmarks include the aggregation of amyloid-β (Aβ), tau and neuroinflammation promoted by several alarmins. Among these is S100B, a small astrocytic homodimeric protein, upregulated in AD, whose multiple biological activities depend on localization, concentration, and assembly state. S100B was reported to inhibit the aggregation and toxicity of Aβ42 and tau similarly to a holdase-type chaperone. This activity is dependent of Ca2+-binding, which triggers the exposure of a regulatory binding cleft at the S100B dimer interface with which amyloidogenic clients dynamically interact. Although the dimer prevails, a significant portion of secreted S100B in the human brain occurs as higher order multimers, whose protective functions remain uncharacterized and which we here investigate. Resorting to ThT-monitored aggregation kinetics, we determined that unlike the dimer, tetrameric S100B inhibits Aβ42 aggregation at sub/equimolar ratios, an effect that persists in the absence of Ca2+ binding. Structural analysis revealed that S100B tetramerization spawns a novel extended cleft accommodating an aggregation-prone surface that mediates interactions with monomeric Aβ client via hydrophobic interactions, as corroborated by Bis-ANS fluorescence and docking analysis. Correspondingly, at high ionic strength that reduces solvation and favours hydrophobic contacts, the inhibition of Aβ42 aggregation by tetrameric S100B is 3-fold increased. Interestingly, this extended Ca2+-independent surface favours Aβ42 as substrate, as tau K18 aggregation is not inhibited by the apo tetramer. Overall, results illustrate a mechanism through which oligomerization of the S100B chaperone fine-tunes anti-aggregation activity and client specificity, highlighting the potential functional relevance of S100B multimers in the regulation of AD proteotoxicity.
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Affiliation(s)
- António J Figueira
- BioISI - Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal. https://twitter.com/Antonio27902425
| | - Guilherme G Moreira
- BioISI - Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal. https://twitter.com/GuilhermeGilMo1
| | - Joana Saavedra
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Portugal
| | - Isabel Cardoso
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Portugal
| | - Cláudio M Gomes
- BioISI - Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
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9
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Lampinen R, Belaya I, Saveleva L, Liddell JR, Rait D, Huuskonen MT, Giniatullina R, Sorvari A, Soppela L, Mikhailov N, Boccuni I, Giniatullin R, Cruz-Haces M, Konovalova J, Koskuvi M, Domanskyi A, Hämäläinen RH, Goldsteins G, Koistinaho J, Malm T, Chew S, Rilla K, White AR, Marsh-Armstrong N, Kanninen KM. Neuron-astrocyte transmitophagy is altered in Alzheimer's disease. Neurobiol Dis 2022; 170:105753. [DOI: 10.1016/j.nbd.2022.105753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/11/2022] [Accepted: 05/09/2022] [Indexed: 10/18/2022] Open
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10
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Diaz-Amarilla P, Arredondo F, Dapueto R, Boix V, Carvalho D, Santi MD, Vasilskis E, Mesquita-Ribeiro R, Dajas-Bailador F, Abin-Carriquiry JA, Engler H, Savio E. Isolation and characterization of neurotoxic astrocytes derived from adult triple transgenic Alzheimer's disease mice. Neurochem Int 2022; 159:105403. [PMID: 35853553 DOI: 10.1016/j.neuint.2022.105403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 06/02/2022] [Accepted: 07/09/2022] [Indexed: 01/16/2023]
Abstract
Alzheimer's disease has been considered mostly as a neuronal pathology, although increasing evidence suggests that glial cells might play a key role in the disease onset and progression. In this sense, astrocytes, with their central role in neuronal metabolism and function, are of great interest for increasing our understanding of the disease. Thus, exploring the morphological and functional changes suffered by astrocytes along the course of this disorder has great therapeutic and diagnostic potential. In this work we isolated and cultivated astrocytes from symptomatic 9-10-months-old adult 3xTg-AD mice, with the aim of characterizing their phenotype and exploring their pathogenic potential. These "old" astrocytes occurring in the 3xTg-AD mouse model of Alzheimer's Disease presented high proliferation rate and differential expression of astrocytic markers compared with controls. They were neurotoxic to primary neuronal cultures both, in neuronal-astrocyte co-cultures and when their conditioned media (ACM) was added into neuronal cultures. ACM caused neuronal GSK3β activation, changes in cytochrome c pattern, and increased caspase 3 activity, suggesting intrinsic apoptotic pathway activation. Exposure of neurons to ACM caused different subcellular responses. ACM application to the somato-dendritic domain in compartmentalised microfluidic chambers caused degeneration both locally in soma/dendrites and distally in axons. However, exposure of axons to ACM did not affect somato-dendritic nor axonal integrity. We propose that this newly described old 3xTg-AD neurotoxic astrocytic population can contribute towards the mechanistic understanding of the disease and shed light on new therapeutical opportunities.
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Affiliation(s)
- Pablo Diaz-Amarilla
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay
| | - Florencia Arredondo
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay; Departamento de Neuroquímica, Instituto de Investigaciones Biológicas Clemente Estable, 11600, Montevideo, Uruguay.
| | - Rosina Dapueto
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay
| | - Victoria Boix
- Departamento de Neuroquímica, Instituto de Investigaciones Biológicas Clemente Estable, 11600, Montevideo, Uruguay
| | - Diego Carvalho
- Departamento de Neuroquímica, Instituto de Investigaciones Biológicas Clemente Estable, 11600, Montevideo, Uruguay
| | - María Daniela Santi
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay
| | - Elena Vasilskis
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay
| | - Raquel Mesquita-Ribeiro
- School of Life Sciences, Medical School Building, University of Nottingham, NG7 2UH, Nottingham, UK
| | - Federico Dajas-Bailador
- School of Life Sciences, Medical School Building, University of Nottingham, NG7 2UH, Nottingham, UK
| | - Juan Andrés Abin-Carriquiry
- Departamento de Neuroquímica, Instituto de Investigaciones Biológicas Clemente Estable, 11600, Montevideo, Uruguay
| | - Henry Engler
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay.
| | - Eduardo Savio
- Area I+D Biomédica, Centro Uruguayo de Imagenología Molecular, 11600, Montevideo, Uruguay.
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11
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Cognitive profiling and proteomic analysis of the modafinil analogue S-CE-123 in experienced aged rats. Sci Rep 2021; 11:23962. [PMID: 34907284 PMCID: PMC8671572 DOI: 10.1038/s41598-021-03372-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/30/2021] [Indexed: 12/22/2022] Open
Abstract
The lack of novel cognitive enhancer drugs in the clinic highlights the prediction problems of animal assays. The objective of the current study was to test a putative cognitive enhancer in a rodent cognitive test system with improved translational validity and clinical predictivity. Cognitive profiling was complemented with post mortem proteomic analysis. Twenty-seven male Lister Hooded rats (26 months old) having learned several cognitive tasks were subchronically treated with S-CE-123 (CE-123) in a randomized blind experiment. Rats were sacrificed after the last behavioural procedure and plasma and brains were collected. A label-free quantification approach was used to characterize proteomic changes in the synaptosomal fraction of the prefrontal cortex. CE-123 markedly enhanced motivation which resulted in superior performance in a new-to-learn operant discrimination task and in a cooperation assay of social cognition, and mildly increased impulsivity. The compound did not affect attention, spatial and motor learning. Proteomic quantification revealed 182 protein groups significantly different between treatment groups containing several proteins associated with aging and neurodegeneration. Bioinformatic analysis showed the most relevant clusters delineating synaptic vesicle recycling, synapse organisation and antioxidant activity. The cognitive profile of CE-123 mapped by the test system resembles that of modafinil in the clinic showing the translational validity of the test system. The findings of modulated synaptic systems are paralleling behavioral results and are in line with previous evidence for the role of altered synaptosomal protein groups in mechanisms of cognitive function.
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12
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Viejo L, Noori A, Merrill E, Das S, Hyman BT, Serrano-Pozo A. Systematic review of human post-mortem immunohistochemical studies and bioinformatics analyses unveil the complexity of astrocyte reaction in Alzheimer's disease. Neuropathol Appl Neurobiol 2021; 48:e12753. [PMID: 34297416 PMCID: PMC8766893 DOI: 10.1111/nan.12753] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/29/2021] [Accepted: 07/12/2021] [Indexed: 12/24/2022]
Abstract
AIMS Reactive astrocytes in Alzheimer's disease (AD) have traditionally been demonstrated by increased glial fibrillary acidic protein (GFAP) immunoreactivity; however, astrocyte reaction is a complex and heterogeneous phenomenon involving multiple astrocyte functions beyond cytoskeletal remodelling. To better understand astrocyte reaction in AD, we conducted a systematic review of astrocyte immunohistochemical studies in post-mortem AD brains followed by bioinformatics analyses on the extracted reactive astrocyte markers. METHODS NCBI PubMed, APA PsycInfo and WoS-SCIE databases were interrogated for original English research articles with the search terms 'Alzheimer's disease' AND 'astrocytes.' Bioinformatics analyses included protein-protein interaction network analysis, pathway enrichment, and transcription factor enrichment, as well as comparison with public human -omics datasets. RESULTS A total of 306 articles meeting eligibility criteria rendered 196 proteins, most of which were reported to be upregulated in AD vs control brains. Besides cytoskeletal remodelling (e.g., GFAP), bioinformatics analyses revealed a wide range of functional alterations including neuroinflammation (e.g., IL6, MAPK1/3/8 and TNF), oxidative stress and antioxidant defence (e.g., MT1A/2A, NFE2L2, NOS1/2/3, PRDX6 and SOD1/2), lipid metabolism (e.g., APOE, CLU and LRP1), proteostasis (e.g., cathepsins, CRYAB and HSPB1/2/6/8), extracellular matrix organisation (e.g., CD44, MMP1/3 and SERPINA3), and neurotransmission (e.g., CHRNA7, GABA, GLUL, GRM5, MAOB and SLC1A2), among others. CTCF and ESR1 emerged as potential transcription factors driving these changes. Comparison with published -omics datasets validated our results, demonstrating a significant overlap with reported transcriptomic and proteomic changes in AD brains and/or CSF. CONCLUSIONS Our systematic review of the neuropathological literature reveals the complexity of AD reactive astrogliosis. We have shared these findings as an online resource available at www.astrocyteatlas.org.
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Affiliation(s)
- Lucía Viejo
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.,MassGeneral Institute for Neurodegenerative Disease (MIND), Charlestown, MA, USA.,Departamento de Farmacología y Terapéutica, Universidad Autónoma de Madrid, Madrid, Spain
| | - Ayush Noori
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.,MassGeneral Institute for Neurodegenerative Disease (MIND), Charlestown, MA, USA.,Harvard College, Cambridge, MA, USA.,MIND Data Science Lab, Cambridge, MA, USA.,Massachusetts Alzheimer's Disease Research Center, Charlestown, MA, USA
| | - Emily Merrill
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.,MassGeneral Institute for Neurodegenerative Disease (MIND), Charlestown, MA, USA.,MIND Data Science Lab, Cambridge, MA, USA
| | - Sudeshna Das
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.,MassGeneral Institute for Neurodegenerative Disease (MIND), Charlestown, MA, USA.,MIND Data Science Lab, Cambridge, MA, USA.,Massachusetts Alzheimer's Disease Research Center, Charlestown, MA, USA.,Harvard Medical School, Harvard University, Boston, MA, USA
| | - Bradley T Hyman
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.,MassGeneral Institute for Neurodegenerative Disease (MIND), Charlestown, MA, USA.,Massachusetts Alzheimer's Disease Research Center, Charlestown, MA, USA.,Harvard Medical School, Harvard University, Boston, MA, USA
| | - Alberto Serrano-Pozo
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA.,MassGeneral Institute for Neurodegenerative Disease (MIND), Charlestown, MA, USA.,Massachusetts Alzheimer's Disease Research Center, Charlestown, MA, USA.,Harvard Medical School, Harvard University, Boston, MA, USA
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13
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Christl J, Verhülsdonk S, Pessanha F, Menge T, Seitz RJ, Kujovic M, Höft B, Supprian T, Lange-Asschenfeldt C. Association of Cerebrospinal Fluid S100B Protein with Core Biomarkers and Cognitive Deficits in Prodromal and Mild Alzheimer's Disease. J Alzheimers Dis 2020; 72:1119-1127. [PMID: 31683478 DOI: 10.3233/jad-190550] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Increased expression of the astroglial Ca2+-binding protein S100B has been observed in various neurodegenerative diseases and also seems to play a role in the unfolding of pathophysiological events at early stages of Alzheimer's disease (AD). OBJECTIVE To examine the association of cerebrospinal fluid (CSF) levels of S100B with 1) established CSF core biomarkers total tau (tau), hyperphosphorylated tau (p-tau), and amyloid β1-42 (Aβ1-42) as well as neuron-specific enolase (NSE) CSF levels and 2) cognition in early AD and mild cognitive impairment (MCI) due to AD (MCI-AD). METHODS Retrospective study assessing 49 pooled charts of Memory Clinic and inpatients diagnosed with AD (N = 26) and MCI-AD (N = 23) according to the National Institute of Aging and Alzheimer's Disease Association (NIA-AA) criteria. Neuropsychological testing was performed with the Consortium to Establish a Registry for AD (CERAD)-Plus battery. RESULTS CSF levels of S100B correlated with NSE, but not the other CSF parameters. Stepwise multiple linear regression, adjusted for age, sex, and educational level, revealed that only increased CSF S100B was independently associated with lower CERAD-Plus total and Mini-Mental Status Examination scores together with poorer performance in wordlist learning (delayed recall and overall performance). We found no independent associations with other CSF biomarkers or cognitive domains. CONCLUSION Our data suggest that CSF S100B may have a diagnostic value particularly at early stages of AD reflecting the significance of neuroinflammatory/astroglial processes. Thus, CSF S100B may complement the established array of available AD biomarkers to improve early stage diagnosis.
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Affiliation(s)
- Julia Christl
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Sandra Verhülsdonk
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Francesca Pessanha
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Til Menge
- Department of Neurology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Rüdiger J Seitz
- Department of Neurology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Milenko Kujovic
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Barbara Höft
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Tillmann Supprian
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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14
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Cristóvão JS, Figueira AJ, Carapeto AP, Rodrigues MS, Cardoso I, Gomes CM. The S100B Alarmin Is a Dual-Function Chaperone Suppressing Amyloid-β Oligomerization through Combined Zinc Chelation and Inhibition of Protein Aggregation. ACS Chem Neurosci 2020; 11:2753-2760. [PMID: 32706972 DOI: 10.1021/acschemneuro.0c00392] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Amyloid beta (Aβ) aggregation and imbalance of metal ions are major hallmarks of Alzheimer's disease (AD). Indeed, amyloid plaques of AD patients are enriched in zinc and Aβ42, and AD related-cognitive decline is dependent on extracellular zinc concentration. In vitro, zinc induces the formation of polymorphic Aβ42 oligomers that delay the formation of amyloid fibers at the expense of increased cellular toxicity. S100B is an inflammatory alarmin and one of the most abundant proteins in the brain and is upregulated in AD and associated with amyloid plaques, where it exerts extracellular functions. Recent findings have uncovered novel neuroprotective functions for S100B as a suppressor of Aβ aggregation and toxicity and in the regulation of zinc homeostasis in neurons. Here we combine biophysical and kinetic approaches to demonstrate that such S100B protective functions converge, making the protein a dual-function chaperone capable of suppressing the formation of toxic Aβ oligomers through both chelation of zinc and inhibition of protein aggregation. From detailed kinetic analysis of Aβ42 aggregation monitoring ThT fluorescence, we show that substoichiometric S100B prevents the formation of toxic off-pathway oligomers that are formed by monomeric Aβ42 in the presence of zinc. Indeed, S100B is effective when added during the lag and transition phases of Aβ42 aggregation, and its action under these circumstances results from its ability to buffer zinc, as it perfectly mimics the effect obtained with the chelating agent EDTA. Further, bioimaging analysis combining transmission electron microscopy and atomic force microscopy confirms that catalytic amounts of S100B partly revert the formation of toxic oligomers. Taken together these results indicate a new role for S100B as a dual chaperone whose distinct functions are interrelated and depend on the relative levels of zinc, S100B, and Aβ, which dynamically evolve during AD.
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Affiliation(s)
- Joana S. Cristóvão
- Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
| | - António J. Figueira
- Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
| | - Ana P. Carapeto
- Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
- Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
| | - Mário S. Rodrigues
- Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
- Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
| | - Isabel Cardoso
- i3S−Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto 4150-180, Portugal
- IBMC−Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto 4150-180, Portugal
| | - Cláudio M. Gomes
- Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
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15
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Kubis-Kubiak A, Dyba A, Piwowar A. The Interplay between Diabetes and Alzheimer's Disease-In the Hunt for Biomarkers. Int J Mol Sci 2020; 21:ijms21082744. [PMID: 32326589 PMCID: PMC7215807 DOI: 10.3390/ijms21082744] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/09/2020] [Accepted: 04/12/2020] [Indexed: 02/07/2023] Open
Abstract
The brain is an organ in which energy metabolism occurs most intensively and glucose is an essential and dominant energy substrate. There have been many studies in recent years suggesting a close relationship between type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) as they have many pathophysiological features in common. The condition of hyperglycemia exposes brain cells to the detrimental effects of glucose, increasing protein glycation and is the cause of different non-psychiatric complications. Numerous observational studies show that not only hyperglycemia but also blood glucose levels near lower fasting limits (72 to 99 mg/dL) increase the incidence of AD, regardless of whether T2DM will develop in the future. As the comorbidity of these diseases and earlier development of AD in T2DM sufferers exist, new AD biomarkers are being sought for etiopathogenetic changes associated with early neurodegenerative processes as a result of carbohydrate disorders. The S100B protein seem to be interesting in this respect as it may be a potential candidate, especially important in early diagnostics of these diseases, given that it plays a role in both carbohydrate metabolism disorders and neurodegenerative processes. It is therefore necessary to clarify the relationship between the concentration of the S100B protein and glucose and insulin levels. This paper draws attention to a valuable research objective that may in the future contribute to a better diagnosis of early neurodegenerative changes, in particular in subjects with T2DM and may be a good basis for planning experiments related to this issue as well as a more detailed explanation of the relationship between the neuropathological disturbances and changes of glucose and insulin concentrations in the brain.
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Affiliation(s)
- Adriana Kubis-Kubiak
- Department of Toxicology, Faculty of Pharmacy, Wroclaw Medical University, 50367 Wroclaw, Poland;
- Correspondence:
| | - Aleksandra Dyba
- Students Science Club of the Department of Toxicology, Faculty of Pharmacy, Wroclaw Medical University, 50367 Wroclaw, Poland;
| | - Agnieszka Piwowar
- Department of Toxicology, Faculty of Pharmacy, Wroclaw Medical University, 50367 Wroclaw, Poland;
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16
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Aladeokin AC, Akiyama T, Kimura A, Kimura Y, Takahashi-Jitsuki A, Nakamura H, Makihara H, Masukawa D, Nakabayashi J, Hirano H, Nakamura F, Saito T, Saido T, Goshima Y. Network-guided analysis of hippocampal proteome identifies novel proteins that colocalize with Aβ in a mice model of early-stage Alzheimer’s disease. Neurobiol Dis 2019; 132:104603. [DOI: 10.1016/j.nbd.2019.104603] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 07/12/2019] [Accepted: 09/02/2019] [Indexed: 12/14/2022] Open
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17
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Cristóvão JS, Gomes CM. S100 Proteins in Alzheimer's Disease. Front Neurosci 2019; 13:463. [PMID: 31156365 PMCID: PMC6532343 DOI: 10.3389/fnins.2019.00463] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 04/24/2019] [Indexed: 01/05/2023] Open
Abstract
S100 proteins are calcium-binding proteins that regulate several processes associated with Alzheimer's disease (AD) but whose contribution and direct involvement in disease pathophysiology remains to be fully established. Due to neuroinflammation in AD patients, the levels of several S100 proteins are increased in the brain and some S100s play roles related to the processing of the amyloid precursor protein, regulation of amyloid beta peptide (Aβ) levels and Tau phosphorylation. S100 proteins are found associated with protein inclusions, either within plaques or as isolated S100-positive puncta, which suggests an active role in the formation of amyloid aggregates. Indeed, interactions between S100 proteins and aggregating Aβ indicate regulatory roles over the aggregation process, which may either delay or aggravate aggregation, depending on disease stage and relative S100 and Aβ levels. Additionally, S100s are also known to influence AD-related signaling pathways and levels of other cytokines. Recent evidence also suggests that metal-ligation by S100 proteins influences trace metal homeostasis in the brain, particularly of zinc, which is also a major deregulated process in AD. Altogether, this evidence strongly suggests a role of S100 proteins as key players in several AD-linked physiopathological processes, which we discuss in this review.
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Affiliation(s)
- Joana S. Cristóvão
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, Lisbon, Portugal
| | - Cláudio M. Gomes
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, Lisbon, Portugal
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18
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AGE-RAGE stress: a changing landscape in pathology and treatment of Alzheimer's disease. Mol Cell Biochem 2019; 459:95-112. [PMID: 31079281 DOI: 10.1007/s11010-019-03553-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 05/04/2019] [Indexed: 12/27/2022]
Abstract
Numerous hypotheses including amyloid cascade, cholinergic, and oxidative have been proposed for pathogenesis of Alzheimer's disease (AD). The data suggest that advanced glycation end products (AGEs) and its receptor RAGE (receptor for AGE) are involved in the pathogenesis of AD. AGE-RAGE stress, defined as a balance between stressors (AGE, RAGE) and anti-stressors (sRAGE, AGE degraders) in favor of stressors, has been implicated in pathogenesis of diseases. AGE and its interaction with RAGE-mediated increase in the reactive oxygen species (ROS) damage brain because of its increased vulnerability to ROS. AGE and ROS increase the synthesis of amyloid β (Aβ) leading to deposition of Aβ and phosphorylation of tau, culminating in formation of plaques and neurofibrillary tangles. ROS increase the synthesis of Aβ, high-mobility group box 1(HMGB1), and S100 that interacts with RAGE to produce additional ROS resulting in enhancement of AD pathology. Elevation of ROS precedes the Aβ plaques formation. Because of involvement of AGE and RAGE in AD pathology, the treatment should be targeted at lowering AGE levels through reduction in consumption and formation of AGE, and lowering expression of RAGE, blocking of RAGE ligand binding, increasing levels of soluble RAGE (sRAGE), and use of antioxidants. The above treatment aspect of AD is lacking. In conclusion, AGE-RAGE stress initiates, and Aβ, HMGB1, and S100 enhance the progression of AD. Reduction of levels of AGE and RAGE, elevation of sRAGE, and antioxidants would be beneficial therapeutic modalities in the prevention, regression, and slowing of progression of AD.
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19
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Arterial stiffness induced by carotid calcification leads to cerebral gliosis mediated by oxidative stress. J Hypertens 2019; 36:286-298. [PMID: 28938336 DOI: 10.1097/hjh.0000000000001557] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Arterial stiffness is a risk factor for cognitive decline and dementia. However, its precise effects on the brain remain unexplored. Using a mouse model of carotid stiffness, we investigated its effect on glial activation and oxidative stress. METHODS Arterial stiffness was induced by the application of calcium chloride to the adventitial region of the right carotid. Superoxide anion production, NADPH activity and levels, as well as glial activation were examined with immunohistochemical and biochemical approaches, 2-week postcalcification. Antioxidant treatment was done with Tempol (1 mmol/l) administered in the drinking water during 2 weeks. RESULTS The current study revealed that arterial stiffness increases the levels of the microglial markers ionized calcium-binding adapter molecule 1 and cluster of differentiation 68 in hippocampus, and of the astrocyte marker, s100 calcium binding protein β in hippocampus and frontal cortex. The cerebral inflammatory effects of arterial stiffness were specific to the brain and not due to systemic inflammation. Treatment with Tempol prevented the increase in superoxide anion in mice with carotid stiffness and attenuated the activation of microglia and astrocytes in the hippocampus. To determine whether the increased oxidative stress derives from NADPH oxidase, superoxide anion production was assessed by incubating brain tissue in the presence of gp91ds-tat, a selective NADPH oxidase 2 inhibitor. This peptide inhibited superoxide anion production to a greater extent in the brains of mice with carotid calcification compared with controls. CONCLUSION Carotid calcification leads to cerebral gliosis mediated by oxidative stress. Correcting arterial stiffness could offer a novel paradigm to protect the brain in populations where stiffness is prominent.
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20
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Michetti F, D'Ambrosi N, Toesca A, Puglisi MA, Serrano A, Marchese E, Corvino V, Geloso MC. The S100B story: from biomarker to active factor in neural injury. J Neurochem 2018; 148:168-187. [DOI: 10.1111/jnc.14574] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/19/2018] [Accepted: 08/15/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Fabrizio Michetti
- Institute of Anatomy and Cell Biology; Università Cattolica del Sacro Cuore; Rome Italy
- IRCCS San Raffaele Scientific Institute; Università Vita-Salute San Raffaele; Milan Italy
| | - Nadia D'Ambrosi
- Department of Biology; Università degli Studi di Roma Tor Vergata; Rome Italy
| | - Amelia Toesca
- Institute of Anatomy and Cell Biology; Università Cattolica del Sacro Cuore; Rome Italy
| | | | - Alessia Serrano
- Institute of Anatomy and Cell Biology; Università Cattolica del Sacro Cuore; Rome Italy
| | - Elisa Marchese
- Institute of Anatomy and Cell Biology; Università Cattolica del Sacro Cuore; Rome Italy
| | - Valentina Corvino
- Institute of Anatomy and Cell Biology; Università Cattolica del Sacro Cuore; Rome Italy
| | - Maria Concetta Geloso
- Institute of Anatomy and Cell Biology; Università Cattolica del Sacro Cuore; Rome Italy
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Role of purinergic receptors in the Alzheimer's disease. Purinergic Signal 2018; 14:331-344. [PMID: 30362042 PMCID: PMC6298926 DOI: 10.1007/s11302-018-9629-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 10/02/2018] [Indexed: 12/13/2022] Open
Abstract
Etiology of the Alzheimer’s disease (AD) is not fully understood. Different pathological processes are considered, such as amyloid deposition, tau protein phosphorylation, oxidative stress (OS), metal ion disregulation, or chronic neuroinflammation. Purinergic signaling is involved in all these processes, suggesting the importance of nucleotide receptors (P2X and P2Y) and adenosine receptors (A1, A2A, A2B, A3) present on the CNS cells. Ecto-purines, ecto-pyrimidines, and enzymes participating in their metabolism are present in the inter-cellular spaces. Accumulation of amyloid-β (Aβ) in brain induces the ATP release into the extra-cellular space, which in turn stimulates the P2X7 receptors. Activation of P2X7 results in the increased synthesis and release of many pro-inflammatory mediators such as cytokines and chemokines. Furthermore, activation of P2X7 leads to the decreased activity of α-secretase, while activation of P2Y2 receptor has an opposite effect. Simultaneous inhibition of P2X7 and stimulation of P2Y2 would therefore be the efficient way of the α-secretase activation. Activation of P2Y2 receptors present in neurons, glia cells, and endothelial cells may have a positive neuroprotective effect in AD. The OS may also be counteracted via the purinergic signaling. ADP and its non-hydrolysable analogs activate P2Y13 receptors, leading to the increased activity of heme oxygenase, which has a cytoprotective activity. Adenosine, via A1 and A2A receptors, affects the dopaminergic and glutaminergic signaling, the brain-derived neurotrophic factor (BNDF), and also changes the synaptic plasticity (e.g., causing a prolonged excitation or inhibition) in brain regions responsible for learning and memory. Such activity may be advantageous in the Alzheimer’s disease.
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Cristóvão JS, Morris VK, Cardoso I, Leal SS, Martínez J, Botelho HM, Göbl C, David R, Kierdorf K, Alemi M, Madl T, Fritz G, Reif B, Gomes CM. The neuronal S100B protein is a calcium-tuned suppressor of amyloid-β aggregation. SCIENCE ADVANCES 2018; 4:eaaq1702. [PMID: 29963623 PMCID: PMC6025902 DOI: 10.1126/sciadv.aaq1702] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 05/22/2018] [Indexed: 05/23/2023]
Abstract
Amyloid-β (Aβ) aggregation and neuroinflammation are consistent features in Alzheimer's disease (AD) and strong candidates for the initiation of neurodegeneration. S100B is one of the most abundant proinflammatory proteins that is chronically up-regulated in AD and is found associated with senile plaques. This recognized biomarker for brain distress may, thus, play roles in amyloid aggregation which remain to be determined. We report a novel role for the neuronal S100B protein as suppressor of Aβ42 aggregation and toxicity. We determined the structural details of the interaction between monomeric Aβ42 and S100B, which is favored by calcium binding to S100B, possibly involving conformational switching of disordered Aβ42 into an α-helical conformer, which locks aggregation. From nuclear magnetic resonance experiments, we show that this dynamic interaction occurs at a promiscuous peptide-binding region within the interfacial cleft of the S100B homodimer. This physical interaction is coupled to a functional role in the inhibition of Aβ42 aggregation and toxicity and is tuned by calcium binding to S100B. S100B delays the onset of Aβ42 aggregation by interacting with Aβ42 monomers inhibiting primary nucleation, and the calcium-bound state substantially affects secondary nucleation by inhibiting fibril surface-catalyzed reactions through S100B binding to growing Aβ42 oligomers and fibrils. S100B protects cells from Aβ42-mediated toxicity, rescuing cell viability and decreasing apoptosis induced by Aβ42 in cell cultures. Together, our findings suggest that molecular targeting of S100B could be translated into development of novel approaches to ameliorate AD neurodegeneration.
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Affiliation(s)
- Joana S. Cristóvão
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Vanessa K. Morris
- Center for Integrated Protein Science Munich, Department of Chemistry, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Isabel Cardoso
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Sónia S. Leal
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Javier Martínez
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Hugo M. Botelho
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Christoph Göbl
- Center for Integrated Protein Science Munich, Department of Chemistry, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Rodrigo David
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Katrin Kierdorf
- Department of Neuropathology, University of Freiburg, Freiburg, Germany
| | - Mobina Alemi
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - Tobias Madl
- Center for Integrated Protein Science Munich, Department of Chemistry, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Günter Fritz
- Department of Neuropathology, University of Freiburg, Freiburg, Germany
| | - Bernd Reif
- Center for Integrated Protein Science Munich, Department of Chemistry, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Cláudio M. Gomes
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Departamento de Química e Bioquímica, Universidade de Lisboa, 1749-016 Lisboa, Portugal
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23
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Ferguson SA, Panos JJ, Sloper D, Varma V. Neurodegenerative Markers are Increased in Postmortem BA21 Tissue from African Americans with Alzheimer's Disease. J Alzheimers Dis 2018; 59:57-66. [PMID: 28582866 DOI: 10.3233/jad-170204] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) presents with an earlier onset age and increased symptom severity in African Americans and Hispanics. OBJECTIVE Although the prevalence of plaques and tangles may not exhibit ethnicity-related differences, levels of neurodegenerative proteins have not been described. METHODS Here, levels of five proteins (i.e., S100B, sRAGE, GDNF, Aβ40, and Aβ42) and the Aβ42/Aβ40 ratio were measured in postmortem samples of the middle temporal gyrus (BA21) from age-matched African Americans and Caucasians with AD (n = 6/gender/ethnicity). RESULTS S100B levels were increased 17% in African Americans (p < 0.003) while sRAGE was mildly decreased (p < 0.09). Aβ42 levels were increased 121% in African Americans (p < 0.02), leading to a 493% increase in the Aβ42/Aβ40 ratio (p < 0.002). Analysis of GDNF levels did not indicate any significant effects. There were no significant effects of gender and no significant ethnicity with gender interactions on any analyte. Effect size calculations indicated "medium" to "very large" effects. CONCLUSION S100B is typically elevated in AD cases; however, the increased levels in African Americans here may be indicative of increased severity in specific populations. Increased Aβ42/Aβ40 ratios in the current study are compatible with increased disease severity and might indicate increased AD pathogenesis in African Americans. Overall, these results are compatible with a hypothesis of increased neuroinflammation in African Americans with AD.
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Affiliation(s)
- Sherry A Ferguson
- Division of Neurotoxicology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR, USA
| | - John J Panos
- Division of Neurotoxicology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR, USA
| | - Daniel Sloper
- Division of Systems Biology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR, USA
| | - Vijayalakshmi Varma
- Division of Systems Biology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR, USA
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24
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Dossi E, Vasile F, Rouach N. Human astrocytes in the diseased brain. Brain Res Bull 2017; 136:139-156. [PMID: 28212850 PMCID: PMC5766741 DOI: 10.1016/j.brainresbull.2017.02.001] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 12/23/2022]
Abstract
Astrocytes are key active elements of the brain that contribute to information processing. They not only provide neurons with metabolic and structural support, but also regulate neurogenesis and brain wiring. Furthermore, astrocytes modulate synaptic activity and plasticity in part by controlling the extracellular space volume, as well as ion and neurotransmitter homeostasis. These findings, together with the discovery that human astrocytes display contrasting characteristics with their rodent counterparts, point to a role for astrocytes in higher cognitive functions. Dysfunction of astrocytes can thereby induce major alterations in neuronal functions, contributing to the pathogenesis of several brain disorders. In this review we summarize the current knowledge on the structural and functional alterations occurring in astrocytes from the human brain in pathological conditions such as epilepsy, primary tumours, Alzheimer's disease, major depressive disorder and Down syndrome. Compelling evidence thus shows that dysregulations of astrocyte functions and interplay with neurons contribute to the development and progression of various neurological diseases. Targeting astrocytes is thus a promising alternative approach that could contribute to the development of novel and effective therapies to treat brain disorders.
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Affiliation(s)
- Elena Dossi
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
| | - Flora Vasile
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, Paris, France.
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25
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Pate KM, Murphy RM. Cerebrospinal Fluid Proteins as Regulators of Beta-amyloid Aggregation and Toxicity. Isr J Chem 2017; 57:602-612. [PMID: 29129937 DOI: 10.1002/ijch.201600078] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Amyloid disorders, such as Alzheimer's, are almost invariably late-onset diseases. One defining diagnostic feature of Alzheimer's disease is the deposition of beta-amyloid as extracellular plaques, primarily in the hippocampus. This raises the question: are there natural protective agents that prevent beta-amyloid from depositing, and is it loss of this protection that leads to onset of disease? Proteins in cerebrospinal fluid (CSF) have been suggested to act as just such natural protective agents. Here, we describe some of the early evidence that led to this suggestion, and we discuss, in greater detail, two CSF proteins that have garnered the bulk of the attention.
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Affiliation(s)
- Kayla M Pate
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison WI 53706 (USA)
| | - Regina M Murphy
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison WI 53706 (USA)
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26
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Robinson AM, Stojanovska V, Rahman AA, McQuade RM, Senior PV, Nurgali K. Effects of Oxaliplatin Treatment on the Enteric Glial Cells and Neurons in the Mouse Ileum. J Histochem Cytochem 2016; 64:530-45. [PMID: 27389702 PMCID: PMC5006136 DOI: 10.1369/0022155416656842] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 06/06/2016] [Indexed: 12/17/2022] Open
Abstract
Oxaliplatin, currently used for treatment of colorectal and other cancers, causes severe gastrointestinal side effects, including nausea, vomiting, diarrhea, and constipation that are attributed to mucosal damage. However, delayed onset and long-term persistence of these side effects suggest that damage to the enteric nervous system (ENS) regulating physiological function of the gastrointestinal tract may also occur. The ENS comprises myenteric and submucosal neurons and enteric glial cells (EGCs). This study aimed to investigate the effects of oxaliplatin treatment on enteric neurons and EGCs within the mouse ileum. BALB/c mice received repeated intraperitoneal injections of oxaliplatin (3 mg/kg, 3 injections/week). Tissues were collected 3, 7, 14, and 21 days from the commencement of treatment. Decreases in glial fibrillary acidic protein-immunoreactive (IR) EGCs and protein gene product 9.5/β-Tubulin III-IR neurons as well as increase in s100β-IR EGCs after chronic oxaliplatin administration were observed in both the myenteric and submucosal plexi. Changes in EGCs were further observed in cross-sections of the ileum at day 14 and confirmed by Western blotting. Alterations in EGCs correlated with loss of myenteric and submucosal neurons in the ileum from oxaliplatin-treated mice. These changes to the ENS may contribute to the mechanisms underlying gastrointestinal side effects associated with oxaliplatin treatment.
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Affiliation(s)
| | | | | | | | | | - Kulmira Nurgali
- Kulmira Nurgali, Western Centre for Health Research & Education, Sunshine Hospital, 176 Furlong Road, St Albans, VIC 3021, Australia.
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27
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Cuajungco MP, Lees GJ, Kydd RR, Tanzi RE, Bush AI. Zinc and Alzheimer's Disease: An Update. Nutr Neurosci 2016; 2:191-208. [DOI: 10.1080/1028415x.1999.11747277] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Batarseh YS, Duong QV, Mousa YM, Al Rihani SB, Elfakhri K, Kaddoumi A. Amyloid-β and Astrocytes Interplay in Amyloid-β Related Disorders. Int J Mol Sci 2016; 17:338. [PMID: 26959008 PMCID: PMC4813200 DOI: 10.3390/ijms17030338] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 02/14/2016] [Accepted: 02/24/2016] [Indexed: 12/17/2022] Open
Abstract
Amyloid-β (Aβ) pathology is known to promote chronic inflammatory responses in the brain. It was thought previously that Aβ is only associated with Alzheimer's disease and Down syndrome. However, studies have shown its involvement in many other neurological disorders. The role of astrocytes in handling the excess levels of Aβ has been highlighted in the literature. Astrocytes have a distinctive function in both neuronal support and protection, thus its involvement in Aβ pathological process may tip the balance toward chronic inflammation and neuronal death. In this review we describe the involvement of astrocytes in Aβ related disorders including Alzheimer's disease, Down syndrome, cerebral amyloid angiopathy, and frontotemporal dementia.
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Affiliation(s)
- Yazan S Batarseh
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA 70504, USA.
| | - Quoc-Viet Duong
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA 70504, USA.
| | - Youssef M Mousa
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA 70504, USA.
| | - Sweilem B Al Rihani
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA 70504, USA.
| | - Khaled Elfakhri
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA 70504, USA.
| | - Amal Kaddoumi
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA 70504, USA.
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29
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Johnson DA, Johnson JA. Nrf2--a therapeutic target for the treatment of neurodegenerative diseases. Free Radic Biol Med 2015; 88:253-267. [PMID: 26281945 PMCID: PMC4809057 DOI: 10.1016/j.freeradbiomed.2015.07.147] [Citation(s) in RCA: 255] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 07/19/2015] [Accepted: 07/20/2015] [Indexed: 12/13/2022]
Abstract
The brain is very sensitive to changes in redox status; thus maintaining redox homeostasis in the brain is critical for the prevention of accumulating oxidative damage. Aging is the primary risk factor for developing neurodegenerative diseases. In addition to age, genetic and environmental risk factors have also been associated with disease development. The primary reactive insults associated with the aging process are a result of oxidative stress (OS) and nitrosative stress (NS). Markers of increased oxidative stress, protein and DNA modification, inflammation, and dysfunctional proteostasis have all been implicated in contributing to the progression of neurodegeneration. The ability of the cell to combat OS/NS and maintain a clearance mechanism for misfolded aggregating proteins determines whether or not it will survive. A critical pathway in this regard is the Nrf2 (nuclear factor erythroid 2-related factor 2)- antioxidant response element (ARE) pathway. Nrf2 activation has been shown to mitigate a number of pathologic mechanisms associated with Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, and multiple sclerosis. This review will focus on the role of Nrf2 in these diseases and the potential for Nrf2 activation to attenuate disease progression.
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Affiliation(s)
- Delinda A Johnson
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA.
| | - Jeffrey A Johnson
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA.
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30
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Delgado-Cortés MJ, Espinosa-Oliva AM, Sarmiento M, Argüelles S, Herrera AJ, Mauriño R, Villarán RF, Venero JL, Machado A, de Pablos RM. Synergistic Deleterious Effect of Chronic Stress and Sodium Azide in the Mouse Hippocampus. Chem Res Toxicol 2015; 28:651-61. [DOI: 10.1021/tx5004408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- María José Delgado-Cortés
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Ana M. Espinosa-Oliva
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Manuel Sarmiento
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Sandro Argüelles
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Antonio J. Herrera
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Raquel Mauriño
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Ruth F. Villarán
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - José L. Venero
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Alberto Machado
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
| | - Rocío M. de Pablos
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Sevilla, 41012-Sevilla, Spain
- Instituto de Biomedicina
de Sevilla (IBiS)-Hospital Universitario Virgen del Rocío/CSIC/Universidad
de Sevilla, 41013-Sevilla, Spain
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31
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Abstract
BACKGROUND S100B level in the blood has been used as a marker for brain damage and blood-brain barrier (BBB) disruption. Elevations of S100B levels after exercise have been observed, suggesting that the BBB may be compromised during exercise. However, an increase in S100B levels may be confounded by other variables. OBJECTIVES The primary objective of this review was to compile findings on the relationship between S100B and exercise in order to determine if this protein is a valid marker for BBB disruptions during exercise. The secondary objective was to consolidate known factors causing S100B increases that may give rise to inaccurate interpretations of S100B levels. DATA SOURCES AND STUDY SELECTION PubMed, Web of Science and ScienceDirect were searched for relevant studies up to January 2013, in which S100B measurements were taken after a bout of exercise. Animal studies were excluded. Variables of interest such as the type of activity, exercise intensities, duration, detection methods, presence and extent of head trauma were examined and compiled. RESULTS This review included 23 studies; 15 (65 %) reported S100B increases after exercise, and among these, ten reported S100B increases regardless of intervention, while five reported increases in only some trials but not others. Eight (35 %) studies reported no increases in S100B levels across all trials. Most baseline S100B levels fall below 0.16 μg/L, with an increase in S100B levels of less than 0.07 μg/L following exercise. Factors that are likely to affect S100B levels include exercise intensity, and duration, presence and extent of head trauma. Several other probable factors influencing S100B elevations are muscle breakdown, level of training and oxidative stress, but current findings are still weak and inconclusive. CONCLUSIONS Elevated S100B levels have been recorded following exercise and are mostly attributed to either an increase in BBB permeability or trauma to the head. However, even in the absence of head trauma, it appears that the BBB may be compromised following exercise, with the severity dependent on exercise intensity.
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32
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Edwards MM, Rodríguez JJ, Gutierrez-Lanza R, Yates J, Verkhratsky A, Lutty GA. Retinal macroglia changes in a triple transgenic mouse model of Alzheimer's disease. Exp Eye Res 2014; 127:252-60. [PMID: 25149907 DOI: 10.1016/j.exer.2014.08.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 08/06/2014] [Accepted: 08/11/2014] [Indexed: 11/18/2022]
Abstract
The retinas of Alzheimer's disease (AD) patients and transgenic AD animal models display amyloid beta deposits and degeneration of ganglion cells. Little is known, however, about the glial changes in the AD retina. The present study used a triple transgenic mouse model (3xTG-AD), which carries mutated human amyloid precursor protein, tau, and presenilin 1 genes and closely mimics the human brain pathology, to investigate retinal glial changes in AD. AD cognitive symptoms are known to begin in the 3xTG-AD mice at four months of age but plaques and tangles are not seen until six to twelve months. Müller cells in 3xTG-AD animals were GFAP-positive, indicating activation, at the earliest time point investigated, nine months. Astrocyte activation was also suggested in the 3xTG-AD mice by an apparent increase in size and process number. Another glial marker, S100, was expressed by astrocytes in both the non-transgenic (NTG) controls and 3xTG-AD retinas. Labeling was predominantly nuclear in nine month non-transgenic (NTG) control mice but was also seen in the cytoplasm and processes at 18 months of age. Interestingly, the nuclear localization was not as prominent in the 3xTG-AD retina even at nine months with labeling observed in astrocyte processes. The diffusion of S100 suggests the possible secretion of this protein, as is seen in the brain, with age and, more profoundly, associated with AD. Several dense, abnormally shaped, opaque structures were noted in all 3xTG-AD mice investigated. These structures, which were enveloped by GFAP and S100-positive astrocytes and Müller cells, were positive for amyloid beta, suggesting that they are amyloid plaques. Staining control retinas with amyloid showed similar structures in 30% of NTG animals but these were fewer in number and not associated with glial activation. The results herein indicate retinal glia activation in the 3xTG-AD mouse retina.
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Affiliation(s)
- Malia M Edwards
- Wilmer Eye Institute, Johns Hopkins Hospital, M023 Smith Building, 400 N. Broadway, Baltimore, MD 21287, USA.
| | - José J Rodríguez
- Department of Neurosciences, University of Basque Country, UPV/EHU, Leioa, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
| | | | - Joseph Yates
- Wilmer Eye Institute, Johns Hopkins Hospital, M023 Smith Building, 400 N. Broadway, Baltimore, MD 21287, USA.
| | - Alexei Verkhratsky
- Department of Neurosciences, University of Basque Country, UPV/EHU, Leioa, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain; Faculty of Life Sciences, The University of Manchester, Oxford Road, Manchester M13 9PT, UK.
| | - Gerard A Lutty
- Wilmer Eye Institute, Johns Hopkins Hospital, M023 Smith Building, 400 N. Broadway, Baltimore, MD 21287, USA.
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Mattson MP, Barger SW. Roles for calcium signaling in structural plasticity and pathology in the hippocampal system. Hippocampus 2013. [DOI: 10.1002/hipo.1993.4500030711] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Mark P. Mattson
- Sanders‐Brown Center on Aging and Department of Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky, U.S.A
| | - Steven W. Barger
- Sanders‐Brown Center on Aging and Department of Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky, U.S.A
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Crutcher KA, Anderton BH, Barger SW, Ohm TG, Snow AD. Cellular and molecular pathology in alzheimer's disease. Hippocampus 2013. [DOI: 10.1002/hipo.1993.4500030730] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Keith A. Crutcher
- Department of Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, U.S.A
| | | | - Steven W. Barger
- Department of Anatomy and Neurobiology, University of Kentucky Medical Center, Lexington, Kentucky, U.S.A
| | - Thomas G. Ohm
- Zentrum der Morphologie, J. W. Goethe‐Universität, Frankfurt, Germany
| | - Alan D. Snow
- Department of Neuropathology, University of Washington, Seattle, Washington, U.S.A
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Affiliation(s)
- Keith A. Crutcher
- Department of Neurosurgery, University of Cincinnati Medical Center, Cincinnati, Ohio, U.S.A
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Wilcock DM, Griffin WST. Down's syndrome, neuroinflammation, and Alzheimer neuropathogenesis. J Neuroinflammation 2013; 10:84. [PMID: 23866266 PMCID: PMC3750399 DOI: 10.1186/1742-2094-10-84] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 05/28/2013] [Indexed: 12/26/2022] Open
Abstract
Down syndrome (DS) is the result of triplication of chromosome 21 (trisomy 21) and is the prevailing cause of mental retardation. In addition to the mental deficiencies and physical anomalies noted at birth, triplication of chromosome 21 gene products results in the neuropathological and cognitive changes of Alzheimer's disease (AD). Mapping of the gene that encodes the precursor protein (APP) of the β-amyloid (Aβ) present in the Aβ plaques in both AD and DS to chromosome 21 was strong evidence that this chromosome 21 gene product was a principal neuropathogenic culprit in AD as well as DS. The discovery of neuroinflammatory changes, including dramatic proliferation of activated glia overexpressing a chromosome 2 gene product--the pluripotent immune cytokine interleukin-1 (IL-1)--and a chromosome 21 gene product--S100B--in the brains of fetuses, neonates, and children with DS opened the possibility that early events in Alzheimer pathogenesis were driven by cytokines. The specific chromosome 21 gene products and the complexity of the mechanisms they engender that give rise to the neuroinflammatory responses noted in fetal development of the DS brain and their potential as accelerators of Alzheimer neuropathogenesis in DS are topics of this review, particularly as they relate to development and propagation of neuroinflammation, the consequences of which are recognized clinically and neuropathologically as Alzheimer's disease.
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Affiliation(s)
- Donna M Wilcock
- Department of Physiology, Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40536, USA
| | - W Sue T Griffin
- Donald W. Reynolds Department of Geriatrics, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, 629 Jack Stephens Dr., Little Rock, AR 72205, USA
- The Geriatric Research Education Clinical Center, Central Arkansas HealthCare System, Little Rock, AR, USA
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Joshi G, Johnson JA. The Nrf2-ARE pathway: a valuable therapeutic target for the treatment of neurodegenerative diseases. ACTA ACUST UNITED AC 2013; 7:218-29. [PMID: 22742419 DOI: 10.2174/157488912803252023] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 05/23/2012] [Accepted: 06/06/2012] [Indexed: 12/13/2022]
Abstract
Modulation of NF-E2 related factor 2 (Nrf2) has been shown in several neurodegenerative disorders. The overexpression of Nrf2 has become a potential therapeutic avenue for various neurodegenerative disorders such as Parkinson, Amyotrophic lateral sclerosis, and Alzheimer's disease. The expression of phase II detoxification enzymes is governed by the cis-acting regulatory element known as antioxidant response element (ARE). The transcription factor Nrf2 binds to ARE thereby transcribing multitude of antioxidant genes. Keap1, a culin 3-based E3 ligase that targets Nrf2 for degradation, sequesters Nrf2 in cytoplasm. Disruption of Keap1-Nrf2 interaction or genetic overexpression of Nrf2 can increase the endogenous antioxidant capacity of the brain thereby rendering protection against oxidative stress in neurodegenerative disorders. This review primarily focuses on recent patents that target Nrf2 overexpression as a promising therapeutic strategy for the treatment of neurodegenerative disorders.
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Affiliation(s)
- Gururaj Joshi
- Division of Pharmaceutical Sciences, School of Pharmacy, 6125 Rennebohm Hall, 777 Highland Avenue, University of Wisconsin, Madison, WI 53705, USA
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Lee YS, Kim H, Kim YH, Roh EJ, Han H, Shin KJ. Synthesis and structure-activity relationships of tri-substituted thiazoles as RAGE antagonists for the treatment of Alzheimer's disease. Bioorg Med Chem Lett 2012; 22:7555-61. [PMID: 23140885 DOI: 10.1016/j.bmcl.2012.10.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 09/28/2012] [Accepted: 10/04/2012] [Indexed: 11/29/2022]
Abstract
A series of thiazole derivatives were designed, and prepared to develop RAGE antagonist for the treatment of Alzheimer's disease (AD). SAR studies were performed to optimize inhibitory activity on Aβ-RAGE binding. SAR studies showed that introducing an amino group at part A was essential for inhibitory activity on Aβ-RAGE binding. Compounds selected from Aβ-RAGE binding screening displayed inhibitory activity on Aβ transport across BBB. They also showed inhibitory activity against Aβ-induced NF-κB activation. These results indicated that our derivatives had a potential as therapeutic agent for the treatment of AD.
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Affiliation(s)
- Yun Suk Lee
- Korea Institute of Science and Technology, 39-1 Hawolgog-dong, Sungbuk-gu, Seoul 136-791, Republic of Korea
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Mechanisms of oxidative damage in multiple sclerosis and neurodegenerative diseases: therapeutic modulation via fumaric acid esters. Int J Mol Sci 2012; 13:11783-11803. [PMID: 23109883 PMCID: PMC3472775 DOI: 10.3390/ijms130911783] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 09/05/2012] [Accepted: 09/07/2012] [Indexed: 12/21/2022] Open
Abstract
Oxidative stress plays a crucial role in many neurodegenerative conditions such as Alzheimer’s disease, amyotrophic lateral sclerosis and Parkinson’s as well as Huntington’s disease. Inflammation and oxidative stress are also thought to promote tissue damage in multiple sclerosis (MS). Recent data point at an important role of anti-oxidative pathways for tissue protection in chronic-progressive MS, particularly involving the transcription factor nuclear factor (erythroid-derived 2)-related factor 2 (Nrf2). Thus, novel therapeutics enhancing cellular resistance to free radicals could prove useful for MS treatment. Here, fumaric acid esters (FAE) are a new, orally available treatment option which had already been tested in phase II/III MS trials demonstrating beneficial effects on relapse rates and magnetic resonance imaging markers. In vitro, application of dimethylfumarate (DMF) leads to stabilization of Nrf2, activation of Nrf2-dependent transcriptional activity and abundant synthesis of detoxifying proteins. Furthermore, application of FAE involves direct modification of the inhibitor of Nrf2, Kelch-like ECH-associated protein 1. On cellular levels, the application of FAE enhances neuronal survival and protects astrocytes against oxidative stress. Increased levels of Nrf2 are detected in the central nervous system of DMF treated mice suffering from experimental autoimmune encephalomyelitis (EAE), an animal model of MS. In EAE, DMF ameliorates the disease course and improves preservation of myelin, axons and neurons. Finally, Nrf2 is also up-regulated in the spinal cord of autopsy specimens from untreated patients with MS, probably as part of a naturally occurring anti-oxidative response. In summary, oxidative stress and anti-oxidative pathways are important players in MS pathophysiology and constitute a promising target for future MS therapies like FAE.
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Herault Y, Duchon A, Velot E, Maréchal D, Brault V. The in vivo Down syndrome genomic library in mouse. PROGRESS IN BRAIN RESEARCH 2012; 197:169-97. [PMID: 22541293 DOI: 10.1016/b978-0-444-54299-1.00009-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mouse models are key elements to better understand the genotype-phenotype relationship and the physiopathology of Down syndrome (DS). Even though the mouse will never recapitulate the whole spectrum of intellectual disabilities observed in the DS, mouse models have been developed over the recent decades and have been used extensively to identify homologous genes or entire regions homologous to the human chromosome 21 (Hsa21) that are necessary or sufficient to induce DS cognitive features. In this chapter, we review the principal mouse DS models which have been selected and engineered over the years either for large genomic regions or for a few or a single gene of interest. Their analyses highlight the complexity of the genetic interactions that are involved in DS cognitive phenotypes and also strengthen the hypothesis on the multigenic nature of DS. This review also addresses future research challenges relative to the making of new models and their combination to go further in the characterization of candidates and modifier of the DS features.
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Affiliation(s)
- Yann Herault
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Translational medicine and Neurogenetics program, IGBMC, CNRS, INSERM, Université de Strasbourg, UMR7104, UMR964, Illkirch, Strasbourg, France.
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41
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Kim JS, Lee SH, Park G, Kim S, Bae SM, Kim DW, Im CH. Clinical Implications of Quantitative Electroencephalography and Current Source Density in Patients with Alzheimer’s Disease. Brain Topogr 2012; 25:461-74. [DOI: 10.1007/s10548-012-0234-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Accepted: 05/24/2012] [Indexed: 10/28/2022]
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Lerner AJ, Gustaw-Rothenberg K, Smyth S, Casadesus G. Retinoids for treatment of Alzheimer's disease. Biofactors 2012; 38:84-9. [PMID: 22419567 DOI: 10.1002/biof.196] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 12/14/2011] [Indexed: 11/11/2022]
Abstract
Retinoids are Vitamin A derivatives involved in cellular regulatory processes including cell differentiation, neurite outgrowth and defense against oxidative stress. Retinoids may also influence Amyloid beta processing upregulation of alpha secretase via ADAM10. Vitamin A and other retinoids also directly inhibit formation of Amyloid fibrils in vivo. These properties of retinoids are relevant to theories of Alzheimer's disease pathogenesis. Retinoids are already used in treatment of acne vulgaris, psoriasis, neuroblastoma and acute promyelocytic leukemia. Clinical studies involving in cognitively impaired older adults with Alzheimer's disease are beginning with a variety of retinoids. These studies need to address safety issues of retinoids in older populations, and hold hope for demonstrating efficacy in translating these basic mechanisms to treatment of a widespread dementing illness.
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Affiliation(s)
- Alan J Lerner
- Department of Neurology, University Hospitals Case Medical Center, Cleveland, OH, USA.
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Michetti F, Corvino V, Geloso MC, Lattanzi W, Bernardini C, Serpero L, Gazzolo D. The S100B protein in biological fluids: more than a lifelong biomarker of brain distress. J Neurochem 2012; 120:644-59. [PMID: 22145907 DOI: 10.1111/j.1471-4159.2011.07612.x] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
S100B is a calcium-binding protein concentrated in glial cells, although it has also been detected in definite extra-neural cell types. Its biological role is still debated. When secreted, S100B is believed to have paracrine/autocrine trophic effects at physiological concentrations, but toxic effects at higher concentrations. Elevated S100B levels in biological fluids (CSF, blood, urine, saliva, amniotic fluid) are thus regarded as a biomarker of pathological conditions, including perinatal brain distress, acute brain injury, brain tumors, neuroinflammatory/neurodegenerative disorders, psychiatric disorders. In the majority of these conditions, high S100B levels offer an indicator of cell damage when standard diagnostic procedures are still silent. The key question remains as to whether S100B is merely leaked from injured cells or is released in concomitance with both physiological and pathological conditions, participating at high concentrations in the events leading to cell injury. In this respect, S100B levels in biological fluids have been shown to increase in physiological conditions characterized by stressful physical and mental activity, suggesting that it may be physiologically regulated and raised during conditions of stress, with a putatively active role. This possibility makes this protein a candidate not only for a biomarker but also for a potential therapeutic target.
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Affiliation(s)
- Fabrizio Michetti
- Institute of Anatomy and Cell Biology, Università Cattolica Sacro Cuore, Roma, Italy.
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Lasagna-Reeves CA, Kayed R. Astrocytes contain amyloid-β annular protofibrils in Alzheimer's disease brains. FEBS Lett 2011; 585:3052-7. [PMID: 21872592 DOI: 10.1016/j.febslet.2011.08.027] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 08/17/2011] [Accepted: 08/18/2011] [Indexed: 10/17/2022]
Abstract
Annular protofibrils (APFs) represent a newly described and distinct class of amyloid structures formed by disease-associated proteins. In vitro, these pore-like structures have been implicated in membrane permeabilization and ion homeostasis via pore formation. Still, their formation and relevance in vivo are poorly understood. Herein, we report that APFs are in human Alzheimer's disease brain samples and that amyloid-β APFs were associated with activated astrocytes. Moreover, we show that amyloid-β APFs in astrocytes adopt a conformation in which the N-terminal region is buried inside the wall of the pore. Our results together with previous studies suggest that the formation of amyloid-β APFs in astrocytes could be a relevant event in the pathogenesis of Alzheimer's disease and validate this amyloidogenic structure as a target for the prevention of the disease.
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Affiliation(s)
- Cristian A Lasagna-Reeves
- George P. and Cynthia Woods Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555-1045, USA.
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45
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Olsson B, Zetterberg H, Hampel H, Blennow K. Biomarker-based dissection of neurodegenerative diseases. Prog Neurobiol 2011; 95:520-34. [PMID: 21524681 DOI: 10.1016/j.pneurobio.2011.04.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 04/06/2011] [Accepted: 04/10/2011] [Indexed: 12/12/2022]
Abstract
The diagnosis of neurodegenerative diseases within neurology and psychiatry are hampered by the difficulty in getting biopsies and thereby validating the diagnosis by pathological findings. Biomarkers for other types of disease have been readily adopted into the clinical practice where for instance troponins are standard tests when myocardial infarction is suspected. However, the use of biomarkers for neurodegeneration has not been fully incorporated into the clinical routine. With the development of cerebrospinal fluid (CSF) biomarkers that reflect pathological events within the central nervous system (CNS), important clinical diagnostic tools are becoming available. This review summarizes the most promising biomarker candidates that may be used to monitor different types of neurodegeneration and protein inclusions, as well as different types of metabolic changes, in living patients in relation to the clinical phenotype and disease progression over time. Our aim is to provide the reader with an updated lexicon on currently available biomarker candidates, how far they have come in development and how well they reflect pathogenic processes in different neurodegenerative diseases. Biomarkers for specific pathogenetic processes would also be valuable tools both to study disease pathogenesis directly in patients and to identify and monitor the effect of novel treatment strategies.
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Affiliation(s)
- Bob Olsson
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden.
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Steiner J, Bogerts B, Schroeter ML, Bernstein HG. S100B protein in neurodegenerative disorders. Clin Chem Lab Med 2011; 49:409-24. [PMID: 21303299 DOI: 10.1515/cclm.2011.083] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
"Classic" neurodegenerative disorders, such as Alzheimer's disease and amyotrophic lateral sclerosis share common pathophysiological features and involve progressive loss of specific neuronal populations, axonal or synaptic loss and dysfunction, reactive astrogliosis, and reduction in myelin. Furthermore, despite the absence of astrogliosis, impaired expression of astrocyte- and oligodendrocyte-related genes has been observed in patients with major psychiatric disorders, including schizophrenia and mood disorders. Because S100B is expressed in astrocytes and oligodendrocytes, its concentration in cerebrospinal fluid (CSF) or serum has been considered a suitable surrogate marker for the diagnostic or prognostic assessment of neurodegeneration. This review summarizes previous postmortem, CSF and serum studies regarding the role of S100B in this context. A general drawback is that only small single-center studies have been performed. Many potential confounding factors exist because of the wide extra-astrocytic and extracerebral expression of S100B. Due to lack of disease specificity, reliance on S100B concentrations for differential diagnostic purposes in cases of suspected neurodegenerative disorders is not recommended. Moreover, there is no consistent evidence for a correlation between disease severity and concentrations of S100B in CSF or serum. Therefore, S100B has limited usefulness for monitoring disease progression.
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Affiliation(s)
- Johann Steiner
- Department of Psychiatry, University of Magdeburg, Magdeburg, Germany.
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Kuljiš RO. The fourth element targeting hypothesis of Alzheimer's disease pathogenesis and pathophysiology. Front Neurol 2010; 1:144. [PMID: 21188267 PMCID: PMC3008923 DOI: 10.3389/fneur.2010.00144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 10/22/2010] [Indexed: 12/20/2022] Open
Abstract
Despite well over a century of research on all forms of the disorder known as Alzheimer's disease (AD), it is still not known whether the condition targets initially neurons, glial cells, other cellular elements in the brain, or components of cells, such as synapses, or molecules independently of their cellular compartmentalization, or otherwise (e.g., specific neuronal circuits). Multiple lines of highly suggestive but as yet insufficient experimental evidence are discussed here to formulate the hypothesis that AD results from primary (i.e., direct and initial) or secondary targeting of what we designate as the Fourth Element Cell (4EC): a relatively recently identified type of brain cell that exhibits features in common with neurons (e.g., synapses, participation in glutamatergic, and GABAergic neurotransmission), astrocytes, oligodendrocytes, and their precursors, but is in other respects clearly distinct from all of them. The 4EC is proposed to be the main target of both: (1) converging insults (i.e., not true "causes") that over time cause sporadic forms of AD as postulated by the Danger Signal Hypothesis - which was not formulated with 4EC in mind - as well as (2) the causes of inherited (i.e., familial) forms of neurodegeneration that resemble certain aspects of the clinical manifestations of sporadic AD.
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Affiliation(s)
- Rodrigo O. Kuljiš
- The Brain-Mind Project, Inc. and Encephalogistics, Inc. Galveston, TX, USA
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Roltsch E, Holcomb L, Young KA, Marks A, Zimmer DB. PSAPP mice exhibit regionally selective reductions in gliosis and plaque deposition in response to S100B ablation. J Neuroinflammation 2010; 7:78. [PMID: 21080947 PMCID: PMC2996465 DOI: 10.1186/1742-2094-7-78] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 11/16/2010] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Numerous studies have reported that increased expression of S100B, an intracellular Ca2+ receptor protein and secreted neuropeptide, exacerbates Alzheimer's disease (AD) pathology. However, the ability of S100B inhibitors to prevent/reverse AD histopathology remains controversial. This study examines the effect of S100B ablation on in vivo plaque load, gliosis and dystrophic neurons. METHODS Because S100B-specific inhibitors are not available, genetic ablation was used to inhibit S100B function in the PSAPP AD mouse model. The PSAPP/S100B-/- line was generated by crossing PSAPP double transgenic males with S100B-/- females and maintained as PSAPP/S100B+/- crosses. Congo red staining was used to quantify plaque load, plaque number and plaque size in 6 month old PSAPP and PSAPP/S100B-/- littermates. The microglial marker Iba1 and astrocytic marker glial fibrillary acidic protein (GFAP) were used to quantify gliosis. Dystrophic neurons were detected with the phospho-tau antibody AT8. S100B immunohistochemistry was used to assess the spatial distribution of S100B in the PSAPP line. RESULTS PSAPP/S100B-/- mice exhibited a regionally selective decrease in cortical but not hippocampal plaque load when compared to PSAPP littermates. This regionally selective reduction in plaque load was accompanied by decreases in plaque number, GFAP-positive astrocytes, Iba1-positive microglia and phospho-tau positive dystrophic neurons. These effects were not attributable to regional variability in the distribution of S100B. Hippocampal and cortical S100B immunoreactivity in PSAPP mice was associated with plaques and co-localized with astrocytes and microglia. CONCLUSIONS Collectively, these data support S100B inhibition as a novel strategy for reducing cortical plaque load, gliosis and neuronal dysfunction in AD and suggest that both extracellular as well as intracellular S100B contribute to AD histopathology.
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Affiliation(s)
- Emily Roltsch
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX, USA
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Reactive astrocytes give neurons less support: implications for Alzheimer's disease. Neurobiol Aging 2010; 33:423.e1-13. [PMID: 21051108 DOI: 10.1016/j.neurobiolaging.2010.09.018] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 09/20/2010] [Accepted: 09/20/2010] [Indexed: 11/20/2022]
Abstract
Astrocytes become activated in Alzheimer's disease (AD), contributing to and reinforcing an inflammatory cascade. It is proposed that by transforming from a basal to a reactive state, astrocytes neglect their neurosupportive functions, thus rendering neurons vulnerable to excitotoxicity and oxidative stress. This review considers 3 important astrocytic functions, that when disrupted, can affect neuronal metabolism. These are the uptake of glucose and release of lactate; the uptake of glutamate and release of glutamine; and the uptake of glutathione precursors and release of glutathione. Conditions under which these functions can be manipulated in vitro, as well as examples of possible loss of astrocytic function in AD, are discussed. It is proposed that the targeting of astrocytes with pharmacological agents that are specifically designed to return astrocytes to a quiescent phenotype could represent a fruitful new angle for the therapeutic treatment of AD and other neurodegenerative disorders.
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Stozicka Z, Zilka N, Novak P, Kovacech B, Bugos O, Novak M. Genetic background modifies neurodegeneration and neuroinflammation driven by misfolded human tau protein in rat model of tauopathy: implication for immunomodulatory approach to Alzheimer's disease. J Neuroinflammation 2010; 7:64. [PMID: 20937161 PMCID: PMC2958906 DOI: 10.1186/1742-2094-7-64] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 10/12/2010] [Indexed: 11/25/2022] Open
Abstract
Background Numerous epidemiological studies demonstrate that genetic background modifies the onset and the progression of Alzheimer's disease and related neurodegenerative disorders. The efficacious influence of genetic background on the disease pathway of amyloid beta has been meticulously described in rodent models. Since the impact of genetic modifiers on the neurodegenerative and neuroinflammatory cascade induced by misfolded tau protein is yet to be elucidated, we have addressed the issue by using transgenic lines expressing the same human truncated tau protein in either spontaneously hypertensive rat (SHR) or Wistar-Kyoto (WKY) genetic background. Methods Brains of WKY and SHR transgenic rats in the terminal stage of phenotype and their age-matched non-transgenic littermates were examined by means of immunohistochemistry and unbiased stereology. Basic measures of tau-induced neurodegeneration (load of neurofibrillary tangles) and neuroinflammation (number of Iba1-positive microglia, their activated morphology, and numbers of microglia immunoreactive for MHCII and astrocytes immunoreactive for GFAP) were quantified with an optical fractionator in brain areas affected by neurofibrillary pathology (pons, medulla oblongata). The stereological data were evaluated using two-way ANOVA and Student's t-test. Results Tau neurodegeneration (neurofibrillary tangles (NFTs), axonopathy) and neuroinflammation (microgliosis, astrocytosis) appeared in both WKY and SHR transgenic rats. Although identical levels of transgene expression in both lines were present, terminally-staged WKY transgenic rats displayed significantly lower final NFT loads than their SHR transgenic counterparts. Interestingly, microglial responses showed a striking difference between transgenic lines. Only 1.6% of microglia in SHR transgenic rats expressed MHCII in spite of having a robust phagocytic phenotype, whereas in WKY transgenic rats, 23.2% of microglia expressed MHCII despite displaying a considerably lower extent of transformation into phagocytic phenotype. Conclusions These results show that the immune response represents a pivotal and genetically variable modifying factor that is able to influence vulnerability to neurodegeneration. Therefore, targeted immunomodulation could represent a prospective therapeutic approach to Alzheimer's disease.
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Affiliation(s)
- Zuzana Stozicka
- Institute of Neuroimmunology, Slovak Academy of Sciences, AD Centre, Dubravska cesta 9, 845 10 Bratislava, Slovak Republic
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