251
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Shadfar S, Hwang CJ, Lim MS, Choi DY, Hong JT. Involvement of inflammation in Alzheimer’s disease pathogenesis and therapeutic potential of anti-inflammatory agents. Arch Pharm Res 2015; 38:2106-19. [DOI: 10.1007/s12272-015-0648-x] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 08/08/2015] [Indexed: 02/06/2023]
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252
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Up-regulation of PSMB4 is associated with neuronal apoptosis after neuroinflammation induced by lipopolysaccharide. J Mol Histol 2015; 46:457-66. [DOI: 10.1007/s10735-015-9637-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 08/10/2015] [Indexed: 12/15/2022]
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253
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Zhang ZG, Li Y, Ng CT, Song YQ. Inflammation in Alzheimer's Disease and Molecular Genetics: Recent Update. Arch Immunol Ther Exp (Warsz) 2015; 63:333-44. [PMID: 26232392 DOI: 10.1007/s00005-015-0351-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 03/03/2015] [Indexed: 01/01/2023]
Abstract
Alzheimer's disease (AD) is a complex age-related neurodegenerative disorder of the central nervous system. Since the first description of AD in 1907, many hypotheses have been established to explain its causes. The inflammation theory is one of them. Pathological and biochemical studies of brains from AD individuals have provided solid evidence of the activation of inflammatory pathways. Furthermore, people with long-term medication of anti-inflammatory drugs have shown a reduced risk to develop the disease. After three decades of genetic study in AD, dozens of loci harboring genetic variants influencing inflammatory pathways in AD patients has been identified through genome-wide association studies (GWAS). The most well-known GWAS risk factor that is responsible for immune response and inflammation in AD development should be APOE ε4 allele. However, a growing number of other GWAS risk AD candidate genes in inflammation have recently been discovered. In the present study, we try to review the inflammation in AD and immunity-associated GWAS risk genes like HLA-DRB5/DRB1, INPP5D, MEF2C, CR1, CLU and TREM2.
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Affiliation(s)
- Zhi-Gang Zhang
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, People's Republic of China
| | - Yan Li
- Energy Research Institute of Shandong Academy of Sciences, Jinan, Shandong, People's Republic of China
| | - Cheung Toa Ng
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, People's Republic of China
| | - You-Qiang Song
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, People's Republic of China. .,State Key Laboratory for Cognitive and Brain Sciences, The University of Hong Kong, Pokfulam, Hong Kong, People's Republic of China.
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254
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Skerrett R, Pellegrino MP, Casali BT, Taraboanta L, Landreth GE. Combined Liver X Receptor/Peroxisome Proliferator-activated Receptor γ Agonist Treatment Reduces Amyloid β Levels and Improves Behavior in Amyloid Precursor Protein/Presenilin 1 Mice. J Biol Chem 2015; 290:21591-602. [PMID: 26163517 DOI: 10.1074/jbc.m115.652008] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Indexed: 12/12/2022] Open
Abstract
Alzheimer disease (AD) is characterized by the extracellular accumulation of amyloid β (Aβ), which is accompanied by a robust inflammatory response in the brain. Both of these pathogenic processes are regulated by nuclear receptors, including the liver X receptors (LXRs) and peroxisome-proliferator receptor γ (PPARγ). Agonists of LXRs have been demonstrated previously to reduce Aβ levels and improve cognitive deficits in AD mouse models by inducing the transcription and lipidation of apolipoprotein E (apoE). Agonists targeting PPARγ reduce the microglial expression of proinflammatory genes and have also been shown to modulate apoE expression. Here we investigate whether a combination therapy with both LXR and PPARγ agonists results in increased benefits in an AD mouse model. We found that the LXR agonist GW3965 and the PPARγ agonist pioglitazone were individually able to increase the levels of apoE and related genes, decrease the expression of proinflammatory genes, and facilitate Aβ decreases in the hippocampus. Combined treatment with both agonists provoked a further increase in the expression of apoE and a decrease in the soluble and deposited forms of Aβ. The decrease in plaques was associated with increased colocalization between microglia and plaques. In addition, the PPARγ agonist in the combined treatment paradigm was able to counteract the elevation in plasma triglycerides that is a side effect of LXR agonist treatment. These results suggest that combined LXR/PPARγ agonist treatment merits further investigation for the treatment of AD.
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Affiliation(s)
- Rebecca Skerrett
- From the Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio 44106 and
| | - Mateus P Pellegrino
- the School of Medicine, University of Campinas, Campinas, Sao Paulo 13083-887, Brazil
| | - Brad T Casali
- From the Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio 44106 and
| | - Laura Taraboanta
- From the Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio 44106 and
| | - Gary E Landreth
- From the Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio 44106 and
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255
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Christensen A, Pike CJ. Menopause, obesity and inflammation: interactive risk factors for Alzheimer's disease. Front Aging Neurosci 2015. [PMID: 26217222 PMCID: PMC4493396 DOI: 10.3389/fnagi.2015.00130] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Alzheimer’s disease (AD) is a multifactorial neurodegenerative disorder, the development of which is regulated by several environmental and genetic risk factors. Two factors theorized to contribute to the initiation and/or progression of AD pathogenesis are age-related increases in inflammation and obesity. These factors may be particularly problematic in women. The onset of menopause in mid-life elevates the vulnerability of women to AD, an increased risk that is likely associated with the depletion of estrogens. Menopause is also linked with an abundance of additional changes, including increased central adiposity and inflammation. Here, we review the current literature to explore the interactions between obesity, inflammation, menopause and AD.
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Affiliation(s)
- Amy Christensen
- Davis School of Gerontology, University of Southern California Los Angeles, CA, USA
| | - Christian J Pike
- Davis School of Gerontology, University of Southern California Los Angeles, CA, USA
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256
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Anastasio TJ. Computational identification of potential multi-drug combinations for reduction of microglial inflammation in Alzheimer disease. Front Pharmacol 2015; 6:116. [PMID: 26097457 PMCID: PMC4456568 DOI: 10.3389/fphar.2015.00116] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/19/2015] [Indexed: 12/31/2022] Open
Abstract
Like other neurodegenerative diseases, Alzheimer Disease (AD) has a prominent inflammatory component mediated by brain microglia. Reducing microglial inflammation could potentially halt or at least slow the neurodegenerative process. A major challenge in the development of treatments targeting brain inflammation is the sheer complexity of the molecular mechanisms that determine whether microglia become inflammatory or take on a more neuroprotective phenotype. The process is highly multifactorial, raising the possibility that a multi-target/multi-drug strategy could be more effective than conventional monotherapy. This study takes a computational approach in finding combinations of approved drugs that are potentially more effective than single drugs in reducing microglial inflammation in AD. This novel approach exploits the distinct advantages of two different computer programming languages, one imperative and the other declarative. Existing programs written in both languages implement the same model of microglial behavior, and the input/output relationships of both programs agree with each other and with data on microglia over an extensive test battery. Here the imperative program is used efficiently to screen the model for the most efficacious combinations of 10 drugs, while the declarative program is used to analyze in detail the mechanisms of action of the most efficacious combinations. Of the 1024 possible drug combinations, the simulated screen identifies only 7 that are able to move simulated microglia at least 50% of the way from a neurotoxic to a neuroprotective phenotype. Subsequent analysis shows that of the 7 most efficacious combinations, 2 stand out as superior both in strength and reliability. The model offers many experimentally testable and therapeutically relevant predictions concerning effective drug combinations and their mechanisms of action.
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Affiliation(s)
- Thomas J Anastasio
- Computational Neurobiology Laboratory, Department of Molecular and Integrative Physiology, Beckman Institute, University of Illinois at Urbana-Champaign Urbana, IL, USA
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257
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Chemerovski-Glikman M, Richman M, Rahimipour S. New Perspectives in Reducing Amyloid Aggregation and Toxicity. Isr J Chem 2015. [DOI: 10.1002/ijch.201500010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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258
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Down syndrome individuals with Alzheimer's disease have a distinct neuroinflammatory phenotype compared to sporadic Alzheimer's disease. Neurobiol Aging 2015; 36:2468-74. [PMID: 26103884 DOI: 10.1016/j.neurobiolaging.2015.05.016] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 05/25/2015] [Accepted: 05/26/2015] [Indexed: 01/24/2023]
Abstract
Down syndrome (DS) is the most common genetic cause of intellectual disability and is primarily caused by the triplication of chromosome 21. The overexpression of amyloid precursor protein gene may be sufficient to drive Alzheimer's disease (AD) neuropathology that is observed in virtually all individuals with DS by the age of 40 years. There is relatively little information about inflammation in the DS brain and how the genetics of DS may alter inflammatory responses and modify the course of AD pathogenesis in this disorder. Using the macrophage classification system of M1, M2a, M2b, and M2c inflammatory phenotypes, we have shown that the early stages of AD are associated with a bias toward an M1 or M2a phenotype. In later stages of AD, markers of M1, M2a and M2c are elevated. We now report the inflammatory phenotype in a DS autopsy series to compare this with the progression in sporadic AD. Tissue from young DS cases (under 40 years of age, pre-AD) show a bias toward M1 and M2b states with little M2a or M2c observed. Older DS cases (over 40 with AD pathology) show a distinct bias toward an M2b phenotype. Importantly, this is distinct from sporadic AD where the M2b phenotype has been rarely, if ever observed in postmortem studies. Stimulated by immune complex activation of microglial cells and toll-like receptor activation, the M2b phenotype represents a unique neuroinflammatory state in diseased brain and may have significant implications for therapeutic intervention for persons with DS.
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259
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Nrdp1 is Associated with Neuronal Apoptosis in Lipopolysaccharide-Induced Neuroinflammation. Neurochem Res 2015; 40:971-9. [PMID: 25896295 DOI: 10.1007/s11064-015-1552-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 02/01/2015] [Accepted: 03/03/2015] [Indexed: 12/12/2022]
Abstract
Neuregulin receptor degradation protein-1 (Nrdp1), a kind of ring finger E3 ubiquitin ligase, is expressed in several adult tissues, including the heart, testis, prostate and brain. Studies of this molecule have demonstrated its great importance in regulating cell growth, apoptosis and oxidative stress in various cell types. However, information regarding its expression and possible function in the central nervous system is still limited. In this study, we performed a neuroinflammation model by lipopolysaccharide (LPS) lateral ventral injection in adult rats. It was found that the expression of Nrdp1 was significantly increased in cerebral cortex after LPS injection. Immunofluorescence indicated that Nrdp1 was located in the neurons, but not astrocytes or microglia. Furthermore, there was a concomitant up-regulation of active caspase-3 and decreased expression of BRUCE (an inhibitor of apoptosis protein). In addition, decreasing Nrdp1 levels by RNA interference in cortical primary neurons reduced active caspase-3 expression but induced up-regulation of BRUCE. Collectively, all these results suggested that Nrdp1 might play a role in neuronal apoptosis by reducing the expression of BRUCE in neuroinflammation after LPS injection.
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260
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Yan H, Kong Y, He B, Huang M, Li J, Zheng J, Liang L, Bi J, Zhao S, Shi L. CYP2J2 rs890293 polymorphism is associated with susceptibility to Alzheimer's disease in the Chinese Han population. Neurosci Lett 2015; 593:56-60. [PMID: 25796175 DOI: 10.1016/j.neulet.2015.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 03/09/2015] [Accepted: 03/16/2015] [Indexed: 12/27/2022]
Abstract
Alzheimer's disease (AD) is a common neurodegenerative disorder characterized by progressive cognitive dysfunction and memory loss. Increasing evidence indicates that inflammation in the brain is a powerful factor in AD progression. Epoxyeicosatrienoic acids, the biologically active derivatives of arachidonic acid, synthesized by cytochrome P450 (CYP) epoxygenases, have been proven to have powerful anti-inflammatory effects. The aim of this study was to examine whether polymorphism in CYP2J2, encoding one of the most common CYP epoxygenase isoforms, is associated with late-onset AD (LOAD). This case-control study genotyped 672 representatives of the Chinese Han population, including 321 LOAD patients and 351 healthy controls matched for age and gender, for the functional rs890293 polymorphism within CYP2J2 by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The CYP2J2 rs890293 T allele and GT+TT genotype were significantly associated with an increased risk of LOAD. Further data stratification according to the presence of the apolipoprotein E (APOE) e4 allele confirmed a strong association between CYP2J2 rs890293 and LOAD, and indicated that the involvement of CYP2J2 in LOAD was independent of ApoE-ϵ4. Our study demonstrated that CYP2J2 rs890293 is a possible predisposing genetic factor for progression of LOAD.
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Affiliation(s)
- Huacheng Yan
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China; Laboratory of Molecular Biology, Center for Disease Control and Prevention of Guangzhou Military Command, Guangzhou 510507, China
| | - Yanying Kong
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China; Department of Pharmacy, Guangzhou First People's Hospital, Guangzhou 510180, China
| | - Baoxia He
- Department of Pharmacy, Henan Cancer Hospital, Zhengzhou 450003, China
| | - Mukun Huang
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China
| | - Jian Li
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China
| | - Jiaqiang Zheng
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China
| | - Lei Liang
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China
| | - Jianjun Bi
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China
| | - Shujin Zhao
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China
| | - Lei Shi
- Department of Pharmacy, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China.
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261
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Latta CH, Sudduth TL, Weekman EM, Brothers HM, Abner EL, Popa GJ, Mendenhall MD, Gonzalez-Oregon F, Braun K, Wilcock DM. Determining the role of IL-4 induced neuroinflammation in microglial activity and amyloid-β using BV2 microglial cells and APP/PS1 transgenic mice. J Neuroinflammation 2015; 12:41. [PMID: 25885682 PMCID: PMC4350455 DOI: 10.1186/s12974-015-0243-6] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 01/10/2015] [Indexed: 12/16/2022] Open
Abstract
Background Microglia are considered the resident immune cells of the central nervous system (CNS). In response to harmful stimuli, an inflammatory reaction ensues in which microglia are activated in a sequenced spectrum of pro- and antiinflammatory phenotypes that are akin to the well-characterized polarization states of peripheral macrophages. A “classically” activated M1 phenotype is known to eradicate toxicity. The transition to an “alternatively” activated M2 phenotype encompasses neuroprotection and repair. In recent years, inflammation has been considered an accompanying pathology in response to the accumulation of extracellular amyloid-β (Aβ) in Alzheimer’s disease (AD). This study aimed to drive an M2a-biased immune phenotype with IL-4 in vitro and in vivo and to determine the subsequent effects on microglial activation and Aβ pathology. Methods In vitro, exogenous IL-4 was applied to BV2 microglial cell cultures to evaluate the temporal progression of microglial responses. In vivo, intracranial injections of an adeno-associate-virus (AAV) viral vector were performed to assess long-term expression of IL-4 in the frontal cortex and hippocampus of Aβ-depositing, APP/PS1 transgenic mice. Quantitative real-time PCR was used to assess the fold change in expression of biomarkers representing each of the microglial phenotypes in both the animal tissue and the BV2 cells. ELISAs quantified IL-4 expression and Aβ levels. Histological staining permitted quantification of microglial and astrocytic activity. Results Both in vitro and in vivo models showed an enhanced M2a phenotype, and the in vivo model revealed a trend toward a decreased trend in Aβ deposition. Conclusions In summary, this study offers insight into the therapeutic potential of microglial immune response in AD.
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Affiliation(s)
- Clare H Latta
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA. .,Department of Biology, The University of Manchester, Manchester, M13 9PL, UK.
| | - Tiffany L Sudduth
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA.
| | - Erica M Weekman
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA. .,Department of Physiology, University of Kentucky, Lexington, KY, 40536, USA.
| | - Holly M Brothers
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA.
| | - Erin L Abner
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA. .,Department of Epidemiology, University of Kentucky, Lexington, KY, 40536, USA.
| | - Gabriel J Popa
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA.
| | - Michael D Mendenhall
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA.
| | - Floracita Gonzalez-Oregon
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA. .,Department of Physiology, University of Kentucky, Lexington, KY, 40536, USA.
| | - Kaitlyn Braun
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA. .,Department of Physiology, University of Kentucky, Lexington, KY, 40536, USA.
| | - Donna M Wilcock
- Department of Physiology, University of Kentucky, Sanders-Brown Center on Aging, Lexington, KY, 40536, USA. .,Department of Physiology, University of Kentucky, Lexington, KY, 40536, USA. .,University of Kentucky, Room 424 Sanders-Brown Center on Aging, 800 S Limestone Street, Lexington, KY, 40536, USA.
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262
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Blair LJ, Frauen HD, Zhang B, Nordhues BA, Bijan S, Lin YC, Zamudio F, Hernandez LD, Sabbagh JJ, Selenica MLB, Dickey CA. Tau depletion prevents progressive blood-brain barrier damage in a mouse model of tauopathy. Acta Neuropathol Commun 2015; 3:8. [PMID: 25775028 PMCID: PMC4353464 DOI: 10.1186/s40478-015-0186-2] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 01/12/2015] [Indexed: 12/31/2022] Open
Abstract
Introduction The blood-brain barrier (BBB) is damaged in tauopathies, including progressive supranuclear palsy (PSP) and Alzheimer’s disease (AD), which is thought to contribute to pathogenesis later in the disease course. In AD, BBB dysfunction has been associated with amyloid beta (Aß) pathology, but the role of tau in this process is not well characterized. Since increased BBB permeability is found in tauopathies without Aß pathology, like PSP, we suspected that tau accumulation alone could not only be sufficient, but even more important than Aß for BBB damage. Results Longitudinal evaluation of brain tissue from the tetracycline-regulatable rTg4510 tau transgenic mouse model showed progressive IgG, T cell and red blood cell infiltration. The Evans blue (EB) dye that is excluded from the brain when the BBB is intact also permeated the brains of rTg4510 mice following peripheral administration, indicative of a bonafide BBB defect, but this was only evident later in life. Thus, despite the marked brain atrophy and inflammation that occurs earlier in this model, BBB integrity is maintained. Interestingly, BBB dysfunction emerged at the same time that perivascular tau emerged around major hippocampal blood vessels. However, when tau expression was suppressed using doxycycline, BBB integrity was preserved, suggesting that the BBB can be stabilized in a tauopathic brain by reducing tau levels. Conclusions For the first time, these data demonstrate that tau alone can initiate breakdown of the BBB, but the BBB is remarkably resilient, maintaining its integrity in the face of marked brain atrophy, neuroinflammation and toxic tau accumulation. Moreover, the BBB can recover integrity when tau levels are reduced. Thus, late stage interventions targeting tau may slow the vascular contributions to cognitive impairment and dementia that occur in tauopathies. Electronic supplementary material The online version of this article (doi:10.1186/s40478-015-0186-2) contains supplementary material, which is available to authorized users.
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263
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Aliaghaei A, Digaleh H, Khodagholi F, Ahmadiani A. Encapsulated Choroid Plexus Epithelial Cells Actively Protect Against Intrahippocampal Aβ-induced Long-Term Memory Dysfunction; Upregulation of Effective Neurogenesis with the Abrogated Apoptosis and Neuroinflammation. J Mol Neurosci 2015; 56:708-21. [PMID: 25634726 DOI: 10.1007/s12031-015-0492-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 01/06/2015] [Indexed: 01/02/2023]
Abstract
Choroid plexus epithelial cells (CPECs) as a secretory epithelium are responsible for the secretion of cerebrospinal fluid (CSF). Beyond this classical tenet, CPECs also synthesize and release many neurotrophic factors such as antioxidants into the CSF, participating in brain homeostasis. In this study, CPECs were isolated from rat's brain and encapsulated in alginate microcapsules. Firstly, functional properties of alginate microcapsules and encapsulated CPECs were examined in vitro. Following, micro-encapsulated CPECs were grafted into rats' brains that were pretreated with Aβ. The in vivo studies include western blotting against Caspase-3 and Terminal-Transferase dUTP Nick End Labeling test that were performed to detect apoptosis in brain tissues. The in vivo part also included immunohistochemistry against Iba-1, glial fibrillary acidic protein, and Brdu to detect microglial migration, gliosis, and neurogenesis, respectively. Moreover, the activity of superoxide dismutase enzyme in hippocampi also was measured, and the memory was assessed by shuttle box apparatus. Our data suggest that transplantation of encapsulated CPECs resulted in a significant decrease in apoptosis, reduced migration microglia, diminished gliosis, increased neurogenesis, and improved long-term memory as well as upregulated antioxidant activity. Since microencapsulated CPECs do not need immunosuppression following implantation, and also we showed their neuroprotective effects against Aβ toxicity and oxidative stress, this may be a suitable candidate for cell therapy in neurological disorders.
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Affiliation(s)
- Abbas Aliaghaei
- NeuroBiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Zhang X, Wang J, Yu T, Du D, Jiang W. Minocycline can delay the development of morphine tolerance, but cannot reverse existing tolerance in the maintenance period of neuropathic pain in rats. Clin Exp Pharmacol Physiol 2014; 42:94-101. [PMID: 25311407 DOI: 10.1111/1440-1681.12316] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 12/16/2022]
Affiliation(s)
- Xin Zhang
- Pain Management Center; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai China
| | - Jing Wang
- Pain Management Center; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai China
| | - Tingting Yu
- Pain Management Center; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai China
| | - Dongping Du
- Pain Management Center; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai China
| | - Wei Jiang
- Pain Management Center; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai China
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265
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Latta CH, Brothers HM, Wilcock DM. Neuroinflammation in Alzheimer's disease; A source of heterogeneity and target for personalized therapy. Neuroscience 2014; 302:103-11. [PMID: 25286385 DOI: 10.1016/j.neuroscience.2014.09.061] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 09/25/2014] [Accepted: 09/26/2014] [Indexed: 12/30/2022]
Abstract
Neuroinflammation has long been known as an accompanying pathology of Alzheimer's disease. Microglia surrounding amyloid plaques in the brain of Auguste D were described in the original publication of Alois Alzheimer. It is only quite recently, however, that we have a more complete appreciation for the diverse roles of neuroinflammation in neurodegenerative disorders such as Alzheimer's. While gaps in our knowledge remain, and conflicting data are abound in the field, our understanding of the complexities and heterogeneous functions of the inflammatory response in Alzheimer's is vastly improved. This review article will discuss some of the roles of neuroinflammation in Alzheimer's disease, in particular, how understanding heterogeneity in the individual inflammatory response can be used in therapeutic development and as a mechanism of personalizing our treatment of the disease.
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Affiliation(s)
- C H Latta
- University of Kentucky, Sanders-Brown Center on Aging, Department of Physiology, Lexington, KY 40536, USA; The University of Manchester, Department of Biology, Manchester M13 9PL, United Kingdom
| | - H M Brothers
- University of Kentucky, Sanders-Brown Center on Aging, Department of Physiology, Lexington, KY 40536, USA
| | - D M Wilcock
- University of Kentucky, Sanders-Brown Center on Aging, Department of Physiology, Lexington, KY 40536, USA.
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266
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Cheng S, LeBlanc KJ, Li L. Triptolide preserves cognitive function and reduces neuropathology in a mouse model of Alzheimer's disease. PLoS One 2014; 9:e108845. [PMID: 25275487 PMCID: PMC4183525 DOI: 10.1371/journal.pone.0108845] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 09/02/2014] [Indexed: 12/02/2022] Open
Abstract
Triptolide, a major bioactive ingredient of a widely used herbal medicine, has been shown to possess multiple pharmacological functions, including potential neuroprotective effects pertinent to Alzheimer's disease (AD) in vitro. However, the therapeutic potential of triptolide for AD in vivo has not been thoroughly evaluated. In the present study, we investigated the impact of peripherally administered triptolide on AD-related behavior and neuropathology in APPswe/PS1ΔE9 (APP/PS1) mice, an established model of AD. Our results showed that two-month treatment with triptolide rescued cognitive function in APP/PS1 mice. Immunohistochemical analyses indicated that triptolide treatment led to a significant decrease in amyloid-β (Aβ) deposition and neuroinflammation in treated mice. In contrast to previous findings in vitro, biochemical analyses showed that triptolide treatment did not significantly affect the production pathway of Aβ in vivo. Intriguingly, further analyses revealed that triptolide treatment upregulated the level of insulin-degrading enzyme, a major Aβ-degrading enzyme in the brain, indicating that triptolide treatment reduced Aβ pathology by enhancing the proteolytic degradation of Aβ. Our findings demonstrate that triptolide treatment ameliorates key behavioral and neuropathological changes found in AD, suggesting that triptolide may serve as a potential therapeutic agent for AD.
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Affiliation(s)
- Shaowu Cheng
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Kyle J. LeBlanc
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Ling Li
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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267
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Malek G, Lad EM. Emerging roles for nuclear receptors in the pathogenesis of age-related macular degeneration. Cell Mol Life Sci 2014; 71:4617-36. [PMID: 25156067 DOI: 10.1007/s00018-014-1709-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/14/2014] [Accepted: 08/18/2014] [Indexed: 12/20/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly in the Western world. Over the last 30 years, our understanding of the pathogenesis of the disease has grown exponentially thanks to the results of countless epidemiology, genetic, histological, and biochemical studies. This information, in turn, has led to the identification of multiple biologic pathways potentially involved in development and progression of AMD, including but not limited to inflammation, lipid and extracellular matrix dysregulation, and angiogenesis. Nuclear receptors are a superfamily of transcription factors that have been shown to regulate many of the pathogenic pathways linked with AMD and as such they are emerging as promising targets for therapeutic intervention. In this review, we will present the fundamental phenotypic features of AMD and discuss our current understanding of the pathobiological disease mechanisms. We will introduce the nuclear receptor superfamily and discuss the current literature on their effects on AMD-related pathophysiology.
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Affiliation(s)
- Goldis Malek
- Department of Ophthalmology, Duke University School of Medicine, 2351 Erwin Road, AERI Room 4006, Durham, NC, 27710, USA,
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268
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SCM-198 inhibits microglial overactivation and attenuates Aβ(1-40)-induced cognitive impairments in rats via JNK and NF-кB pathways. J Neuroinflammation 2014; 11:147. [PMID: 25134526 PMCID: PMC4156960 DOI: 10.1186/s12974-014-0147-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 08/06/2014] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Neuroinflammation mediated by overactivated microglia plays a key role in many neurodegenerative diseases, including Alzheimer's disease (AD). In this study, we investigated for the first time the anti-neuroinflammatory effects and possible mechanisms of SCM-198 (an alkaloid extracted from Herbaleonuri), which was previously found highly cardioprotective, both in vitro and in vivo. METHODS For in vitro experiments, lipopolysaccharide (LPS) or β-amyloid(1-40) (Aβ(1-40)) was applied to induce microglial overactivation. Proinflammatory mediators were measured and activations of NF-κB and mitogen-activated protein kinases' (MAPKs) pathways were investigated. Further protective effect of SCM-198 was evaluated in microglia-neuron co-culture assay and Sprague-Dawley (SD) rats intrahippocampally-injected with Aβ(1-40). RESULTS SCM-198 reduced expressions of nitric oxide (NO), TNF-α, IL-1β and IL-6 possibly via, at least partially, inhibiting c-Jun N-terminal kinase (JNK) and NF-κB signaling pathways in microglia. Co-culture assay showed that activated microglia pretreated with SCM-198 led to less neuron loss and decreased phosphorylation of tau and extracellular signal-regulated kinase (ERK) in neurons. Besides, SCM-198 also directly protected against Aβ(1-40)-induced neuronal death and lactate dehydrogenase (LDH) release in primary cortical neurons. For in vivo studies, SCM-198 significantly enhanced cognitive performances of rats 12 days after intrahippocampal injections of aged Aβ(1-40) peptides in the Morris water maze (MWM), accompanied by less hippocampal microglial activation, decreased synaptophysin loss and phosphorylation of ERK and tau. Co-administration of donepezil and SCM-198 resulted in a slight cognitive improvement in SD rats 50 days after intrahippocampal injections of aged Aβ(1-40) peptides as compared to only donepezil or SCM-198 treated group. CONCLUSIONS Our findings are the first to report that SCM-198 has considerable anti-neuroinflammatory effects on inhibiting microglial overactivation and might become a new potential drug candidate for AD therapy in the future.
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269
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Spielman LJ, Little JP, Klegeris A. Inflammation and insulin/IGF-1 resistance as the possible link between obesity and neurodegeneration. J Neuroimmunol 2014; 273:8-21. [PMID: 24969117 DOI: 10.1016/j.jneuroim.2014.06.004] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 06/03/2014] [Accepted: 06/04/2014] [Indexed: 12/17/2022]
Abstract
Obesity is a growing epidemic that contributes to several brain disorders including Alzheimer's, Parkinson's, and Huntington's diseases. Obesity could promote these diseases through several different mechanisms. Here we review evidence supporting the involvement of two recently recognized factors linking obesity with neurodegeneration: the induction of pro-inflammatory cytokines and onset of insulin and insulin-like growth factor 1 (IGF-1) resistance. Excess peripheral pro-inflammatory mediators, some of which can cross the blood brain barrier, may trigger neuroinflammation, which subsequently exacerbates neurodegeneration. Insulin and IGF-1 resistance leads to weakening of neuroprotective signaling by these molecules and can contribute to onset of neurodegenerative diseases.
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Affiliation(s)
- Lindsay J Spielman
- Department of Biology, University of British Columbia Okanagan Campus, 3333 University Way, Kelowna, BC, V1V 1V7 Canada
| | - Jonathan P Little
- School of Health and Exercise Sciences, University of British Columbia Okanagan Campus, 3333 University Way, Kelowna, BC, V1V 1V7 Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, 3333 University Way, Kelowna, BC, V1V 1V7 Canada.
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270
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Kim M, Kim SO, Lee M, Lee JH, Jung WS, Moon SK, Kim YS, Cho KH, Ko CN, Lee EH. Tetramethylpyrazine, a natural alkaloid, attenuates pro-inflammatory mediators induced by amyloid β and interferon-γ in rat brain microglia. Eur J Pharmacol 2014; 740:504-11. [PMID: 24975095 DOI: 10.1016/j.ejphar.2014.06.037] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 06/19/2014] [Accepted: 06/19/2014] [Indexed: 12/11/2022]
Abstract
Neuroinflammation has been consistently reported as a pathological hallmark of Alzheimer׳s disease and other neurodegenerative diseases. Microglial cells are activated by diverse pathological stimuli and play key roles in development of neuroinflammation. Amyloid β peptide (Aβ), the major constituent of amyloid plaques in Alzheimer׳s brain, is known to activate cultured microglial cells to produce increased amounts of proinflammatory and neurotoxic factors. Tetramethylpyrazine (TMP) is the main bioactive alkaloid isolated from Ligusticum chuanxiong. TMP has multiple pharmacological activities, including anti-oxidant, anti-inflammatory, and anti-cancer effects. Neuroprotective potential of TMP has been demonstrated in animal models of neuropathologies. However, the efficacy of this compound for controlling Aβ-related neuropathology has not been explored yet. We examined the efficacy of TMP in the repression of inflammatory response in cultured microglial cells stimulated with Aβ25-35 in the presence of interferon (IFN)-γ. TMP significantly inhibited the Aβ25-35 and IFN-γ-stimulated productions of nitric oxide, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, monocyte chemoattractant protein-1, and intracellular reactive oxygen species from primary microglial cells. TMP also effectively reduced Aβ25-35 and IFN-γ-elicited NF-κB activation. In organotypic hippocampal slice cultures (OHSCs), TMP significantly blocked Aβ25-35-induced reactive oxygen species generation and phosphorylation of Akt. Furthermore, TMP also inhibited Aβ1-42-induced TNF-α and IL-1β production in primary microglial cells and neuronal death in OHSCs. These results suggest that TMP provide a possible therapeutic approach for alleviating the inflammatory progression of Alzheimer׳s disease.
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Affiliation(s)
- Mia Kim
- Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Sung-Ok Kim
- College of Oriental Medicine, Daegu Haany University, Daegu 706-060, Republic of Korea
| | - Moonsung Lee
- Department of East-West Medical Science, Kyung Hee University, Yongin-si 446-701, Republic of Korea
| | - Joon H Lee
- Myunggok Eye Research Institute, Konyang University College of Medicine, Nonsan 320-711, Republic of Korea
| | - Woo-Sang Jung
- Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Sang-Kwan Moon
- Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Young-Suk Kim
- Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Ki-Ho Cho
- Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Chang-Nam Ko
- Department of Cardiovascular & Neurologic Diseases (Stroke Center), Hospital of Oriental Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Eunjoo H Lee
- Department of East-West Medical Science, Kyung Hee University, Yongin-si 446-701, Republic of Korea.
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271
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Song Y, Shen J, Lin Y, Shen J, Wu X, Yan Y, Zhou L, Zhang H, Zhou Y, Cao M, Liu Y. Up-regulation of podoplanin involves in neuronal apoptosis in LPS-induced neuroinflammation. Cell Mol Neurobiol 2014; 34:839-49. [PMID: 24821010 DOI: 10.1007/s10571-014-0060-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 04/04/2014] [Indexed: 02/01/2023]
Abstract
Podoplanin (PDPN) is a mucin-type transmembrane sialoglycoprotein expressed in multiple tissues in adult animals, including the brain, lungs, kidney, and lymphoid organs. Studies of this molecule have demonstrated its great importance in tumor metastasis, platelet aggregation, and lymphatic vessel formation. However, information regarding its regulation and possible function in the central nervous system is still limited. In this study, we performed a neuroinflammatory model by lipopolysaccharide (LPS) lateral ventral injection in adult rats and detected increased expression of PDPN in the brain cortex. Immunofluorescence indicated that PDPN was located in the neurons, but not astrocytes. Moreover, there was a concomitant up-regulation of active caspase-3, cyclin D1, and CDK4 in vivo and vitro studies. In addition, the expression of these three proteins in cortical primary neurons was decreased after knocking down PDPN by siRNA. Collectively, all these results suggested that the up-regulation of PDPN might be involved in neuronal apoptosis in neuroinflammation after LPS injection.
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Affiliation(s)
- Yan Song
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, People's Republic of China
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272
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273
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Tamboli IY, Heo D, Rebeck GW. Extracellular proteolysis of apolipoprotein E (apoE) by secreted serine neuronal protease. PLoS One 2014; 9:e93120. [PMID: 24675880 PMCID: PMC3968057 DOI: 10.1371/journal.pone.0093120] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 03/02/2014] [Indexed: 12/20/2022] Open
Abstract
Under normal conditions, brain apolipoprotein E (apoE) is secreted and lipidated by astrocytes, then taken up by neurons via receptor mediated endocytosis. Free apoE is either degraded in intraneuronal lysosomal compartments or released. Here we identified a novel way by which apoE undergoes proteolysis in the extracellular space via a secreted neuronal protease. We show that apoE is cleaved in neuronal conditioned media by a secreted serine protease. This apoE cleavage was inhibited by PMSF and α1-antichymotrypsin, but not neuroserpin-1 or inhibitors of thrombin and cathepsin G, supporting its identity as a chymotrypsin like protease. In addition, apoE incubation with purified chymotrypsin produced a similar pattern of apoE fragments. Analysis of apoE fragments by mass spectrometry showed cleavages occurring at the C-terminal side of apoE tryptophan residues, further supporting our identification of cleavage by chymotrypsin like protease. Hippocampal neurons were more efficient in mediating this apoE cleavage than cortical neurons. Proteolysis of apoE4 generated higher levels of low molecular weight fragments compared to apoE3. Primary glial cultures released an inhibitor of this proteolytic activity. Together, these studies reveal novel mechanism by which apoE can be regulated and therefore could be useful in designing apoE directed AD therapeutic approaches.
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Affiliation(s)
- Irfan Y. Tamboli
- Department of Neuroscience, Georgetown University, Washington DC., United States of America
| | - Dongeun Heo
- Department of Neuroscience, Georgetown University, Washington DC., United States of America
| | - G. William Rebeck
- Department of Neuroscience, Georgetown University, Washington DC., United States of America
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274
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Wincewicz D, Braszko JJ. Angiotensin II AT1 receptor blockade by telmisartan reduces impairment of spatial maze performance induced by both acute and chronic stress. J Renin Angiotensin Aldosterone Syst 2014; 16:495-505. [DOI: 10.1177/1470320314526269] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 01/26/2014] [Indexed: 01/02/2023] Open
Affiliation(s)
- Dominik Wincewicz
- Department of Clinical Pharmacology, Medical University of Bialystok, Poland
| | - Jan J Braszko
- Department of Clinical Pharmacology, Medical University of Bialystok, Poland
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275
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Wan Z, Mah D, Simtchouk S, Klegeris A, Little JP. Globular adiponectin induces a pro-inflammatory response in human astrocytic cells. Biochem Biophys Res Commun 2014; 446:37-42. [PMID: 24582565 DOI: 10.1016/j.bbrc.2014.02.077] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 02/11/2014] [Indexed: 12/18/2022]
Abstract
Neuroinflammation, mediated in part by activated brain astrocytes, plays a critical role in the development of neurodegenerative disorders, including Alzheimer's disease (AD). Adiponectin is the most abundant adipokine secreted from adipose tissue and has been reported to exert both anti- and pro-inflammatory effects in peripheral tissues; however, the effects of adiponectin on astrocytes remain unknown. Shifts in peripheral concentrations of adipokines, including adiponectin, could contribute to the observed link between midlife adiposity and increased AD risk. The aim of the present study was to characterize the effects of globular adiponectin (gAd) on pro-inflammatory cytokine mRNA expression and secretion in human U373 MG astrocytic cells and to explore the potential involvement of nuclear factor (NF)-κB, p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK) and phosphatidylinositide 3-kinases (PI3K) signaling pathways in these processes. We demonstrated expression of adiponectin receptor 1 (adipoR1) and adipoR2 in U373 MG cells and primary human astrocytes. gAd induced secretion of interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1, and gene expression of IL-6, MCP-1, IL-1β and IL-8 in U373 MG cells. Using specific inhibitors, we found that NF-κB, p38MAPK and ERK1/2 pathways are involved in gAd-induced induction of cytokines with ERK1/2 contributing the most. These findings provide evidence that gAd may induce a pro-inflammatory phenotype in human astrocytes.
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Affiliation(s)
- Zhongxiao Wan
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Dorrian Mah
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Svetlana Simtchouk
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan, Kelowna, BC, Canada
| | - Jonathan P Little
- School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, BC, Canada.
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276
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Auriel E, Regev K, Korczyn AD. Nonsteroidal anti-inflammatory drugs exposure and the central nervous system. HANDBOOK OF CLINICAL NEUROLOGY 2014; 119:577-584. [PMID: 24365321 DOI: 10.1016/b978-0-7020-4086-3.00038-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used agents in clinical practice. They are employed as anti-inflammatory, analgesic, and antipyretic agents for a wide spectrum of clinical conditions. Their anti-inflammatory properties are primarily due to inhibition of prostaglandin synthesis. In this paper we review the neurological effects associated with the use of NSAIDs. Acute CNS toxicity related to NSAID use is pervasive and varied. A prospective study looking at ibuprofen overdose noted that 30% of patients experience CNS effects ranging from drowsiness to coma. Case reports have identified numerous neurologic sequelae including ataxia, vertigo, dizziness, recurrent falls, nystagmus, headache, encephalopathy, and disorientation. Seizures have also been reported, mostly after overdose ingestions, but even therapeutic doses have occasionally been associated with seizures. One of the important neurologic side-effects attributed to the use of NSAIDs is aseptic meningitis. The clinical signs of drug-induced meningitis are similar to those of infectious meningitis and include fever, headache, photophobia, and stiff neck. The laboratory findings are also similar, including cerebrospinal fluid (CSF) pleocytosis of several hundred or thousand cells, mainly neutrophils, elevated levels of protein, normal or low glucose levels and negative cultures. Drug-induced meningitis is a transient disorder with an excellent prognosis. Most or all drugs used for the treatment of headache, including NSAIDs, may cause a condition known as medication overuse headache - a refractory chronic daily headache that tends to resolve following discontinuation of the analgesics. Reye's syndrome is a rare severe illness occurring mainly in children and adolescents and characterized by abnormal liver function, vomiting, and encephalopathy, with a mortality rate approaching 40%. The pathogenesis is currently unknown, but commonly the syndrome is preceded by a viral episode, with an intermediate latent period of 3-5 days. An association with aspirin use is strongly suggested. Aspirin, the classic and most commonly used NSAID, has a well-documented effect in inhibiting intravascular clotting, thus reducing the occurrence of ischemic strokes and other vascular events. NSAIDs, however, have a double impact on coagulation. On the one hand, most agents inhibit the synthesis of thromboxane in the platelets, thereby inhibiting coagulation. On the other hand, they also inhibit the production of prostacyclin by endothelial cells, resulting in a prothrombotic state. Selective inhibition of COX-2 by drugs such as rofecoxib (Vioxx) and valdecoxib (Bextra) results in specific inhibition of synthesis of prostaglandins participating in inflammation and was found to lead to vascular complications including an increased risk for stroke. The connection between inflammation and neuronal degeneration is well established. Most studies, including the prospective Rotterdam study, have found an inverse correlation between the use of NSAIDs and the risk for dementia. Two meta-analyses have found 40% and 25% reduction, respectively, in the risk of Alzheimer's disease among NSAID users. However, some large, well designed studies failed to confirm these results, and some even found that NSAID use is associated with cognitive decline. The clinical impact of NSAIDs on Parkinson's disease (PD) remains unclear. While some studies showed that chronic NSAID use is protective against PD, other studies could not confirm the existence of a significant relationship. A recent meta-analysis indicated that the use of non-aspirin NSAID, particularly ibuprofen, reduces the risk of PD by 15% while the use of aspirin did not show any effect.
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Affiliation(s)
- Eitan Auriel
- Department of Neurology, Tel-Aviv University, Ramat-Aviv, Israel
| | - Keren Regev
- Department of Neurology, Tel-Aviv University, Ramat-Aviv, Israel
| | - Amos D Korczyn
- Department of Neurology, Tel-Aviv University, Ramat-Aviv, Israel.
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277
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Wild-type neural progenitors divide and differentiate normally in an amyloid-rich environment. J Neurosci 2013; 33:17335-41. [PMID: 24174666 DOI: 10.1523/jneurosci.1917-13.2013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Adult neurogenesis is modulated by a balance of extrinsic signals and intrinsic responses that maintain production of new granule cells in the hippocampus. Disorders that disrupt the proliferative niche can impair this process, and alterations in adult neurogenesis have been described in human autopsy tissue and transgenic mouse models of Alzheimer's disease. Because exogenous application of aggregated Aβ peptide is neurotoxic in vitro and extracellular Aβ deposits are the main pathological feature recapitulated by mouse models, cell-extrinsic effects of Aβ accumulation were thought to underlie the breakdown of hippocampal neurogenesis observed in Alzheimer's models. We tested this hypothesis using a bigenic mouse in which transgenic expression of APP was restricted to mature projection neurons. These mice allowed us to examine how wild-type neural progenitor cells responded to high levels of Aβ released from neighboring granule neurons. We find that the proliferation, determination, and survival of hippocampal adult-born granule neurons are unaffected in the APP bigenic mice, despite abundant amyloid pathology and robust neuroinflammation. Our findings suggest that Aβ accumulation is insufficient to impair adult hippocampal neurogenesis, and that factors other than amyloid pathology may account for the neurogenic deficits observed in transgenic models with more widespread APP expression.
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278
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Abstract
Traumatic injury or disease of the spinal cord and brain elicits multiple cellular and biochemical reactions that together cause or are associated with neuropathology. Specifically, injury or disease elicits acute infiltration and activation of immune cells, death of neurons and glia, mitochondrial dysfunction, and the secretion of substrates that inhibit axon regeneration. In some diseases, inflammation is chronic or non-resolving. Ligands that target PPARs (peroxisome proliferator-activated receptors), a group of ligand-activated transcription factors, are promising therapeutics for neurologic disease and CNS injury because their activation affects many, if not all, of these interrelated pathologic mechanisms. PPAR activation can simultaneously weaken or reprogram the immune response, stimulate metabolic and mitochondrial function, promote axon growth and induce progenitor cells to differentiate into myelinating oligodendrocytes. PPAR activation has beneficial effects in many pre-clinical models of neurodegenerative diseases and CNS injury; however, the mechanisms through which PPARs exert these effects have yet to be fully elucidated. In this review we discuss current literature supporting the role of PPAR activation as a therapeutic target for treating traumatic injury and degenerative diseases of the CNS.
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279
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Sheridan GK, Murphy KJ. Neuron-glia crosstalk in health and disease: fractalkine and CX3CR1 take centre stage. Open Biol 2013; 3:130181. [PMID: 24352739 PMCID: PMC3877844 DOI: 10.1098/rsob.130181] [Citation(s) in RCA: 252] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
An essential aspect of normal brain function is the bidirectional interaction and communication between neurons and neighbouring glial cells. To this end, the brain has evolved ligand-receptor partnerships that facilitate crosstalk between different cell types. The chemokine, fractalkine (FKN), is expressed on neuronal cells, and its receptor, CX(3)CR1, is predominantly expressed on microglia. This review focuses on several important functional roles for FKN/CX(3)CR1 in both health and disease of the central nervous system. It has been posited that FKN is involved in microglial infiltration of the brain during development. Microglia, in turn, are implicated in the developmental synaptic pruning that occurs during brain maturation. The abundance of FKN on mature hippocampal neurons suggests a homeostatic non-inflammatory role in mechanisms of learning and memory. There is substantial evidence describing a role for FKN in hippocampal synaptic plasticity. FKN, on the one hand, appears to prevent excess microglial activation in the absence of injury while promoting activation of microglia and astrocytes during inflammatory episodes. Thus, FKN appears to be neuroprotective in some settings, whereas it contributes to neuronal damage in others. Many progressive neuroinflammatory disorders that are associated with increased microglial activation, such as Alzheimer's disease, show disruption of the FKN/CX(3)CR1 communication system. Thus, targeting CX(3)CR1 receptor hyperactivation with specific antagonists in such neuroinflammatory conditions may eventually lead to novel neurotherapeutics.
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Affiliation(s)
- Graham K Sheridan
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
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280
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Wang CC, Tsai YJ, Hsieh YC, Lin RJ, Lin CL. The aqueous extract from Toona sinensis leaves inhibits microglia-mediated neuroinflammation. Kaohsiung J Med Sci 2013; 30:73-81. [PMID: 24444536 PMCID: PMC7118447 DOI: 10.1016/j.kjms.2013.09.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 08/30/2013] [Indexed: 01/24/2023] Open
Abstract
The leaves of Toona sinensis, a well‐known traditional oriental medicine, have been prescribed for the treatment of enteritis and infection. Recently, aqueous extracts of Toona sinensis leaves (TSL‐1) have demonstrated many biological effects both in vitro and in vivo. In the central nervous system, microglial activation and their proinflammatory responses are considered an important therapeutic strategy for neuroinflammatory disorders such as cerebral ischemia, Alzheimer's disease, and Parkinson's disease. The present study attempted to validate the effect of TSL‐1 on microglia‐mediated neuroinflammation stimulated by lipopolysaccharide (LPS). As inflammatory parameters, the production of nitric oxide (NO), inducible NO synthase, and tumor necrosis factor‐α were evaluated. Our results demonstrate that TSL‐1 suppresses LPS‐induced NO production, tumor necrosis factor‐α secretion, and inducible NO synthase protein expression in a concentration‐dependent manner, without causing cytotoxicity. In addition, the inhibitory effects of TSL‐1 in LPS‐stimulated BV‐2 microglia were extended to post‐treatment suggesting the therapeutic potential of TSL‐1. Therefore, this work provides the future evaluation of the role of TSL‐1 in the treatment of neurodegenerative diseases by inhibition of inflammatory mediator production in activated microglia.
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Affiliation(s)
- Chao-Chuan Wang
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yee-Jean Tsai
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ya-Ching Hsieh
- Department of Medical Research, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan
| | - Rong-Jyh Lin
- Department of Parasitology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chih-Lung Lin
- Department of Neurosurgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Faculty of Medicine, Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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281
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Hornik TC, Neniskyte U, Brown GC. Inflammation induces multinucleation of Microglia via PKC inhibition of cytokinesis, generating highly phagocytic multinucleated giant cells. J Neurochem 2013; 128:650-61. [PMID: 24117490 DOI: 10.1111/jnc.12477] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/18/2013] [Accepted: 09/29/2013] [Indexed: 12/15/2022]
Abstract
Microglia are brain macrophages, which can undergo multinucleation to give rise to multinucleated giant cells that accumulate with ageing and some brain pathologies. However, the origin, regulation and function of multinucleate microglia remain unclear. We found that inflammatory stimuli, including lipopolysaccharide, amyloid β, α-synuclein, tumour necrosis factor-α and interferon γ, but not interleukin-4, induced multinucleation of cultured microglia: primary rat cortical microglia and the murine microglial cell line BV-2. Inflammation-induced multinucleation was prevented by a protein kinase C (PKC) inhibitor Gö6976 (100 nM) and replicated by a PKC activator phorbol myristate acetate (160 nM). Multinucleation was reversible and not because of cell fusion or phagocytosis, but rather failure of cytokinesis. Time-lapse imaging revealed that some dividing cells failed to abscise, even after formation of long cytoplasmic bridges, followed by retraction of bridge and reversal of cleavage furrow to form multinucleate cells. Multinucleate microglia were larger and 2-4 fold more likely to phagocytose large beads and both dead and live PC12 cells. We conclude that multinucleate microglia are reversibly generated by inflammation via PKC inhibition of cytokinesis, and may have specialized functions/dysfunctions including the phagocytosis of other cells. Inflammation resulted in the accumulation of multiple nuclei per cell in cultured microglia. This multinucleation was reversible and due to a PKC-dependent block of the last step of cell division. Multinucleate microglia were larger and had a greater capacity to phagocytose other cells, suggesting they might remove neurons in the brain.
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Affiliation(s)
- Tamara C Hornik
- Department of Biochemistry, University of Cambridge, Cambridge, UK
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282
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Kurapati KRV, Atluri VSR, Samikkannu T, Nair MPN. Ashwagandha (Withania somnifera) reverses β-amyloid1-42 induced toxicity in human neuronal cells: implications in HIV-associated neurocognitive disorders (HAND). PLoS One 2013; 8:e77624. [PMID: 24147038 PMCID: PMC3797707 DOI: 10.1371/journal.pone.0077624] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 09/04/2013] [Indexed: 01/22/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by progressive dysfunction of memory and higher cognitive functions with abnormal accumulation of extracellular amyloid plaques and intracellular neurofibrillary tangles throughout cortical and limbic brain regions. At present no curative treatment is available, and research focuses on drugs for slowing disease progression or providing prophylaxis. Withania somnifera (WS) also known as 'ashwagandha' is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer. However, there is a paucity of data on the potential neuroprotective effects of W.somnifera against β-Amyloid (1-42)-induced neuropathogenesis. In the present study, we have tested the neuroprotective effects of methanol:Chloroform (3:1) extract of ashwagandha against β-amyloid induced toxicity and HIV-1Ba-L (clade B) infection using a human neuronal SK-N-MC cell line. Our results showed that β-amyloid induced cytotoxic effects in SK-N-MC cells as shown by decreased cell growth when tested individually. Also, confocal microscopic analysis showed decreased spine density, loss of spines and decreased dendrite diameter, total dendrite and spine area in clade B infected SK-N-MC cells compared to uninfected cells. However, when ashwagandha was added to β-amyloid treated and HIV-1 infected samples, the toxic effects were neutralized. Further, the MTT cell viability assays and the peroxisome proliferator-activated receptor-γ (PPARγ) levels supported these observations indicating the neuroprotective effect of WS root extract against β-amyloid and HIV-1Ba-L (clade B) induced neuro-pathogenesis.
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Affiliation(s)
- Kesava Rao Venkata Kurapati
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Modesto A. Maidique Campus, Miami, Florida, United States of America
| | - Venkata Subba Rao Atluri
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Modesto A. Maidique Campus, Miami, Florida, United States of America
| | - Thangavel Samikkannu
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Modesto A. Maidique Campus, Miami, Florida, United States of America
| | - Madhavan P. N. Nair
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Modesto A. Maidique Campus, Miami, Florida, United States of America
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283
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Regulation of prostaglandin F2α against β amyloid clearance and its inflammation induction through LXR/RXR heterodimer antagonism in microglia. Prostaglandins Other Lipid Mediat 2013; 106:45-52. [DOI: 10.1016/j.prostaglandins.2013.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 09/04/2013] [Accepted: 09/17/2013] [Indexed: 12/13/2022]
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284
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Armato U, Chiarini A, Chakravarthy B, Chioffi F, Pacchiana R, Colarusso E, Whitfield JF, Dal Prà I. Calcium-sensing receptor antagonist (calcilytic) NPS 2143 specifically blocks the increased secretion of endogenous Aβ42 prompted by exogenous fibrillary or soluble Aβ25-35 in human cortical astrocytes and neurons-therapeutic relevance to Alzheimer's disease. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1832:1634-52. [PMID: 23628734 DOI: 10.1016/j.bbadis.2013.04.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/28/2013] [Accepted: 04/18/2013] [Indexed: 11/17/2022]
Abstract
The "amyloid-β (Aβ) hypothesis" posits that accumulating Aβ peptides (Aβs) produced by neurons cause Alzheimer's disease (AD). However, the Aβs contribution by the more numerous astrocytes remains undetermined. Previously we showed that fibrillar (f)Aβ25-35, an Aβ42 proxy, evokes a surplus endogenous Aβ42 production/accumulation in cortical adult human astrocytes. Here, by using immunocytochemistry, immunoblotting, enzymatic assays, and highly sensitive sandwich ELISA kits, we investigated the effects of fAβ25-35 and soluble (s)Aβ25-35 on Aβ42 and Aβ40 accumulation/secretion by human cortical astrocytes and HCN-1A neurons and, since the calcium-sensing receptor (CaSR) binds Aβs, their modulation by NPS 2143, a CaSR allosteric antagonist (calcilytic). The fAβ25-35-exposed astrocytes and surviving neurons produced, accumulated, and secreted increased amounts of Aβ42, while Aβ40 also accrued but its secretion was unchanged. Accordingly, secreted Aβ42/Aβ40 ratio values rose for astrocytes and neurons. While slightly enhancing Aβ40 secretion by fAβ25-35-treated astrocytes, NPS 2143 specifically suppressed the fAβ25-35-elicited surges of endogenous Aβ42 secretion by astrocytes and neurons. Therefore, NPS 2143 addition always kept Aβ42/Aβ40 values to baseline or lower levels. Mechanistically, NPS 2143 decreased total CaSR protein complement, transiently raised proteasomal chymotrypsin activity, and blocked excess NO production without affecting the ongoing increases in BACE1/β-secretase and γ-secretase activity in fAβ25-35-treated astrocytes. Compared to fAβ25-35, sAβ25-35 also stimulated Aβ42 secretion by astrocytes and neurons and NPS 2143 specifically and wholly suppressed this effect. Therefore, since NPS 2143 thwarts any Aβ/CaSR-induced surplus secretion of endogenous Aβ42 and hence further vicious cycles of Aβ self-induction/secretion/spreading, calcilytics might effectively prevent/stop the progression to full-blown AD.
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Affiliation(s)
- Ubaldo Armato
- Department of Life and Reproduction Sciences, University of Verona Medical School, Verona, Italy.
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285
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Ma Y, Bao J, Zhao X, Shen H, Lv J, Ma S, Zhang X, Li Z, Wang S, Wang Q, Ji J. Activated cyclin-dependent kinase 5 promotes microglial phagocytosis of fibrillar β-amyloid by up-regulating lipoprotein lipase expression. Mol Cell Proteomics 2013; 12:2833-44. [PMID: 23816988 DOI: 10.1074/mcp.m112.026864] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Amyloid plaques are crucial for the pathogenesis of Alzheimer disease (AD). Phagocytosis of fibrillar β-amyloid (Aβ) by activated microglia is essential for Aβ clearance in Alzheimer disease. However, the mechanism underlying Aβ clearance in the microglia remains unclear. In this study, we performed stable isotope labeling of amino acids in cultured cells for quantitative proteomics analysis to determine the changes in protein expression in BV2 microglia treated with or without Aβ. Among 2742 proteins identified, six were significantly up-regulated and seven were down-regulated by Aβ treatment. Bioinformatic analysis revealed strong over-representation of membrane proteins, including lipoprotein lipase (LPL), among proteins regulated by the Aβ stimulus. We verified that LPL expression increased at both mRNA and protein levels in response to Aβ treatment in BV2 microglia and primary microglial cells. Silencing of LPL reduced microglial phagocytosis of Aβ, but did not affect degradation of internalized Aβ. Importantly, we found that enhanced cyclin-dependent kinase 5 (CDK5) activity by increasing p35-to-p25 conversion contributed to LPL up-regulation and promoted Aβ phagocytosis in microglia, whereas inhibition of CDK5 reduced LPL expression and Aβ internalization. Furthermore, Aβ plaques was increased with reducing p25 and LPL level in APP/PS1 mouse brains, suggesting that CDK5/p25 signaling plays a crucial role in microglial phagocytosis of Aβ. In summary, our findings reveal a potential role of the CDK5/p25-LPL signaling pathway in Aβ phagocytosis by microglia and provide a new insight into the molecular pathogenesis of Alzheimer disease.
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Affiliation(s)
- Yuanhui Ma
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
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286
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Wyss-Coray T, Rogers J. Inflammation in Alzheimer disease-a brief review of the basic science and clinical literature. Cold Spring Harb Perspect Med 2013; 2:a006346. [PMID: 22315714 DOI: 10.1101/cshperspect.a006346] [Citation(s) in RCA: 671] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Biochemical and neuropathological studies of brains from individuals with Alzheimer disease (AD) provide clear evidence for an activation of inflammatory pathways, and long-term use of anti-inflammatory drugs is linked with reduced risk to develop the disease. As cause and effect relationships between inflammation and AD are being worked out, there is a realization that some components of this complex molecular and cellular machinery are most likely promoting pathological processes leading to AD, whereas other components serve to do the opposite. The challenge will be to find ways of fine tuning inflammation to delay, prevent, or treat AD.
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Affiliation(s)
- Tony Wyss-Coray
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California 94305-5235, USA; Geriatric Research Education and Clinical Center, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304, USA
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287
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Silencing of the P2X(7) receptor enhances amyloid-β phagocytosis by microglia. Biochem Biophys Res Commun 2013; 434:363-9. [PMID: 23562658 DOI: 10.1016/j.bbrc.2013.03.079] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 03/26/2013] [Indexed: 11/21/2022]
Abstract
P2X7 receptor (P2X7R) is an ATP-gated cation channel that promotes microglia activation and plays a critical role in the pathogenesis of Alzheimer's disease. Inhibiting P2X7R indirectly reduces the rate of amyloid-β (Aβ)-induced neurodegeneration by suppressing secretion of inflammatory factors from activated microglia. We used RNA interference to silence P2X7R in microglial cells in vitro and found it markedly increased microglial phagocytosis of Aβ1-42. Increased phagocytic activity was dependent on decreasing the rate of interleukin-1β release from microglia and required inhibition of the COX-2 pathway. Modulation of microglial phagocytosis and secretion via silencing P2X7R may be a promising therapeutic option for the treatment of Alzheimer's disease.
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288
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Medeiros R, Kitazawa M, Passos GF, Baglietto-Vargas D, Cheng D, Cribbs DH, LaFerla FM. Aspirin-triggered lipoxin A4 stimulates alternative activation of microglia and reduces Alzheimer disease-like pathology in mice. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 182:1780-9. [PMID: 23506847 DOI: 10.1016/j.ajpath.2013.01.051] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 01/15/2013] [Accepted: 01/17/2013] [Indexed: 12/29/2022]
Abstract
Microglia play an essential role in innate immunity, homeostasis, and neurotropic support in the central nervous system. In Alzheimer disease (AD), these cells may affect disease progression by modulating the buildup of β-amyloid (Aβ) or releasing proinflammatory cytokines and neurotoxic substances. Discovering agents capable of increasing Aβ uptake by phagocytic cells is of potential therapeutic interest for AD. Lipoxin A4 (LXA4) is an endogenous lipid mediator with potent anti-inflammatory properties directly involved in inflammatory resolution, an active process essential for appropriate host responses, tissue protection, and the return to homeostasis. Herein, we demonstrate that aspirin-triggered LXA4 (15 μg/kg) s.c., twice a day, reduced NF-κB activation and levels of proinflammatory cytokines and chemokines, as well as increased levels of anti-inflammatory IL-10 and transforming growth factor-β. Such changes in the cerebral milieu resulted in recruitment of microglia in an alternative phenotype, as characterized by the up-regulation of YM1 and arginase-1 and the down-regulation of inducible nitric oxide synthase expression. Microglia in an alternative phenotype-positive cells demonstrated improved phagocytic function, promoting clearance of Aβ deposits and ultimately leading to reduction in synaptotoxicity and improvement in cognition. Our data indicate that activating LXA4 signaling may represent a novel therapeutic approach for AD.
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Affiliation(s)
- Rodrigo Medeiros
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697-4545, USA
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289
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Fanelli F, Sepe S, D’Amelio M, Bernardi C, Cristiano L, Cimini A, Cecconi F, Ceru' MP, Moreno S. Age-dependent roles of peroxisomes in the hippocampus of a transgenic mouse model of Alzheimer's disease. Mol Neurodegener 2013; 8:8. [PMID: 23374228 PMCID: PMC3599312 DOI: 10.1186/1750-1326-8-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 01/29/2013] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Alzheimer's Disease (AD) is a progressive neurodegenerative disease, especially affecting the hippocampus. Impairment of cognitive and memory functions is associated with amyloid β-peptide-induced oxidative stress and alterations in lipid metabolism. In this scenario, the dual role of peroxisomes in producing and removing ROS, and their function in fatty acids β-oxidation, may be critical. This work aims to investigating the possible involvement of peroxisomes in AD onset and progression, as studied in a transgenic mouse model, harboring the human Swedish familial AD mutation. We therefore characterized the peroxisomal population in the hippocampus, focusing on early, advanced, and late stages of the disease (3, 6, 9, 12, 18 months of age). Several peroxisome-related markers in transgenic and wild-type hippocampal formation were comparatively studied, by a combined molecular/immunohistochemical/ultrastructural approach. RESULTS Our results demonstrate early and significant peroxisomal modifications in AD mice, compared to wild-type. Indeed, the peroxisomal membrane protein of 70 kDa and acyl-CoA oxidase 1 are induced at 3 months, possibly reflecting the need for efficient fatty acid β-oxidation, as a compensatory response to mitochondrial dysfunction. The concomitant presence of oxidative damage markers and the altered expression of antioxidant enzymes argue for early oxidative stress in AD. During physiological and pathological brain aging, important changes in the expression of peroxisome-related proteins, also correlating with ongoing gliosis, occur in the hippocampus. These age- and genotype-based alterations, strongly dependent on the specific marker considered, indicate metabolic and/or numerical remodeling of peroxisomal population. CONCLUSIONS Overall, our data support functional and biogenetic relationships linking peroxisomes to mitochondria and suggest peroxisomal proteins as biomarkers/therapeutic targets in pre-symptomatic AD.
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Affiliation(s)
- Francesca Fanelli
- Department of Biology-LIME, University “Roma Tre”, viale Marconi 446, 00146, Rome, Italy
- University Campus Bio-Medico, via Alvaro del Portillo 21, 00128, Rome, Italy
| | - Sara Sepe
- Department of Biology-LIME, University “Roma Tre”, viale Marconi 446, 00146, Rome, Italy
| | - Marcello D’Amelio
- IRCCS S. Lucia Foundation, via del Fosso di Fiorano 65, 00143, Rome, Italy
- University Campus Bio-Medico, via Alvaro del Portillo 21, 00128, Rome, Italy
| | - Cinzia Bernardi
- Department of Radiological Sciences and Laboratory Medicine, UOC Pathological Anatomy, San Filippo Neri Hospital, via Martinotti 20, 00135, Rome, Italy
| | - Loredana Cristiano
- Department of Life, Health and Environmental Sciences, University of L’Aquila, piazzale Salvatore Tommasi 1, 67100, Coppito, (AQ), Italy
| | - AnnaMaria Cimini
- Department of Life, Health and Environmental Sciences, University of L’Aquila, piazzale Salvatore Tommasi 1, 67100, Coppito, (AQ), Italy
| | - Francesco Cecconi
- IRCCS S. Lucia Foundation, via del Fosso di Fiorano 65, 00143, Rome, Italy
- Department of Biology, University of Rome ‘Tor Vergata’, via della Ricerca Scientifica, 00133, Rome, Italy
| | - Maria Paola Ceru'
- Department of Life, Health and Environmental Sciences, University of L’Aquila, piazzale Salvatore Tommasi 1, 67100, Coppito, (AQ), Italy
| | - Sandra Moreno
- Department of Biology-LIME, University “Roma Tre”, viale Marconi 446, 00146, Rome, Italy
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290
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Involvement of early growth response-2 (Egr-2) in lipopolysaccharide-induced neuroinflammation. J Mol Histol 2013; 44:249-57. [PMID: 23307302 DOI: 10.1007/s10735-013-9482-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Accepted: 01/02/2013] [Indexed: 02/05/2023]
Abstract
Early growth response-2 (Egr-2) protein is a transcription factor, which belongs to Egr family which involve in modulating the peripheral immune response, by means of the induction of differentiation of lymphocyte precursors, activation of T and B cells. Egr-2 plays essential roles in peripheral nerve myelination, adipogenesis, tissue repair and fibrosis, immune tolerance; however, its regulation and role in central nervous system (CNS) remain poorly understood. In contrast to Egr-1, which has been extensively investigated, the regulation and function of Egr-2 remains less well characterized. To elaborate whether Egr-2 was involved in CNS injury, we performed a neuroinflammatory model by lipopolysaccharide (LPS) lateral ventral injection in adult rats. Egr-2 expression was strongly induced in active glia cells (astrocytes and microglias) in inflamed brain cortex. In vitro studies indicated that the upregulation of Egr-2 may be involved in the subsequent glia cellular activation following LPS exposure; and knock down of Egr-2 in primary mixed glial cultures (MGC) by siRNA showed that Egr-2 promoted the synthesis of TNF-α. Collectively, these results suggested Egr-2 may be important in host defense in CNS immune response, which might provide a potential target to the treatment of neuroinflammation.
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291
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Richman M, Perelman A, Gertler A, Rahimipour S. Effective Targeting of Aβ to Macrophages by Sonochemically Prepared Surface-Modified Protein Microspheres. Biomacromolecules 2012; 14:110-6. [DOI: 10.1021/bm301401b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Michal Richman
- Department
of Chemistry and ‡Department of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Alex Perelman
- Department
of Chemistry and ‡Department of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Asaf Gertler
- Department
of Chemistry and ‡Department of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Shai Rahimipour
- Department
of Chemistry and ‡Department of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
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292
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Mechanisms underlying the rapid peroxisome proliferator-activated receptor-γ-mediated amyloid clearance and reversal of cognitive deficits in a murine model of Alzheimer's disease. J Neurosci 2012; 32:10117-28. [PMID: 22836247 DOI: 10.1523/jneurosci.5268-11.2012] [Citation(s) in RCA: 275] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Alzheimer's disease is associated with a disruption of amyloid β (Aβ) homeostasis, resulting in the accumulation and subsequent deposition of Aβ peptides within the brain. The peroxisome proliferator-activated receptor-γ (PPARγ) is a ligand-activated nuclear receptor that acts in a coupled metabolic cycle with Liver X Receptors (LXRs) to increase brain apolipoprotein E (apoE) levels. apoE functions to promote the proteolytic clearance of soluble forms of Aβ, and we found that the synthetic PPARγ agonist, pioglitazone, stimulated Aβ degradation by both microglia and astrocytes in an LXR and apoE-dependent manner. Remarkably, a brief 9 d oral treatment of APPswe/PS1Δe9 mice with pioglitazone resulted in dramatic reductions in brain levels of soluble and insoluble Aβ levels which correlated with the loss of both diffuse and dense-core plaques within the cortex. The removal of preexisting amyloid deposits was associated with the appearance of abundant Aβ-laden microglia and astrocytes. Pioglitazone treatment resulted in the phenotypic polarization of microglial cells from a proinflammatory M1 state, into an anti-inflammatory M2 state that was associated with enhanced phagocytosis of deposited forms of amyloid. The reduction in amyloid levels was associated with a reversal of contextual memory deficits in the drug-treated mice. These data provide a mechanistic explanation for how PPARγ activation facilitates amyloid clearance and supports the therapeutic utility of PPARγ agonists for the treatment of Alzheimer's disease.
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293
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Drouin-Ouellet J, Cicchetti F. Inflammation and neurodegeneration: the story 'retolled'. Trends Pharmacol Sci 2012; 33:542-51. [PMID: 22944460 DOI: 10.1016/j.tips.2012.07.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 06/30/2012] [Accepted: 07/11/2012] [Indexed: 01/18/2023]
Abstract
Toll-like receptors (TLRs) play a crucial role in innate immunity by recognizing conserved motifs predominantly found in microorganisms. Increasing evidence supports a role for TLRs in sterile inflammation as observed in neurodegenerative disorders. This includes work suggesting a contribution for these receptors to the pathophysiology of Alzheimer's disease (AD), Parkinson's disease (PD), and related disorders. In this review, the potential role of TLRs in the context of protein aggregation, neuronal degeneration, and genetic risk factors is addressed. In particular, we discuss the evidence derived from experimental models of both AD and PD which suggests that activation of TLRs can have beneficial and detrimental effects on pathological features such as protein aggregation and neuronal death. A deeper understanding of these dichotomous observations could be used for therapeutic benefit.
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294
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Polajnar M, Ceru S, Kopitar-Jerala N, Zerovnik E. Human stefin B normal and patho-physiological role: molecular and cellular aspects of amyloid-type aggregation of certain EPM1 mutants. Front Mol Neurosci 2012; 5:88. [PMID: 22936898 PMCID: PMC3426797 DOI: 10.3389/fnmol.2012.00088] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Accepted: 08/03/2012] [Indexed: 11/24/2022] Open
Abstract
Epilepsies are characterized by abnormal electrophysiological activity of the brain. Among various types of inherited epilepsies different epilepsy syndromes, among them progressive myoclonus epilepsies with features of ataxia and neurodegeneration, are counted. The progressive myoclonus epilepsy of type 1 (EPM1), also known as Unverricht-Lundborg disease presents with features of cerebellar atrophy and increased oxidative stress. It has been found that EPM1 is caused by mutations in human cystatin B gene (human stefin B). We first describe the role of protein aggregation in other neurodegenerative conditions. Protein aggregates appear intraneurally but are also excreted, such as is the case with senile plaques of amyloid-β (Aβ) that accumulate in the brain parenchyma and vessel walls. A common characteristic of such diseases is the change of the protein conformation toward β secondary structure that accounts for the strong tendency of such proteins to aggregate and form amyloid fibrils. Second, we describe the patho-physiology of EPM1 and the normal and aberrant roles of stefin B in a mouse model of the disease. Furthermore, we discuss how the increased protein aggregation observed with some of the mutants of human stefin B may relate to the neurodegeneration that occurs in rare EPM1 patients. Our hypothesis (Ceru et al., 2005) states that some of the EPM1 mutants of human stefin B may undergo aggregation in neural cells, thus gaining additional toxic function (apart from loss of normal function). Our in vitro experiments thus far have confirmed that four mutants undergo increased aggregation relative to the wild-type protein. It has been shown that the R68X mutant forms amyloid-fibrils very rapidly, even at neutral pH and forms perinuclear inclusions, whereas the G4R mutant exhibits a prolonged lag phase, during which the toxic prefibrillar aggregates accumulate and are scattered more diffusely over the cytoplasm. Initial experiments on the G50E and Q71P missense EPM1 mutants are described.
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Affiliation(s)
- Mira Polajnar
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute Ljubljana, Slovenia
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295
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Cribbs DH, Berchtold NC, Perreau V, Coleman PD, Rogers J, Tenner AJ, Cotman CW. Extensive innate immune gene activation accompanies brain aging, increasing vulnerability to cognitive decline and neurodegeneration: a microarray study. J Neuroinflammation 2012; 9:179. [PMID: 22824372 PMCID: PMC3419089 DOI: 10.1186/1742-2094-9-179] [Citation(s) in RCA: 357] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 07/23/2012] [Indexed: 12/16/2022] Open
Abstract
Background This study undertakes a systematic and comprehensive analysis of brain gene expression profiles of immune/inflammation-related genes in aging and Alzheimer’s disease (AD). Methods In a well-powered microarray study of young (20 to 59 years), aged (60 to 99 years), and AD (74 to 95 years) cases, gene responses were assessed in the hippocampus, entorhinal cortex, superior frontal gyrus, and post-central gyrus. Results Several novel concepts emerge. First, immune/inflammation-related genes showed major changes in gene expression over the course of cognitively normal aging, with the extent of gene response far greater in aging than in AD. Of the 759 immune-related probesets interrogated on the microarray, approximately 40% were significantly altered in the SFG, PCG and HC with increasing age, with the majority upregulated (64 to 86%). In contrast, far fewer immune/inflammation genes were significantly changed in the transition to AD (approximately 6% of immune-related probesets), with gene responses primarily restricted to the SFG and HC. Second, relatively few significant changes in immune/inflammation genes were detected in the EC either in aging or AD, although many genes in the EC showed similar trends in responses as in the other brain regions. Third, immune/inflammation genes undergo gender-specific patterns of response in aging and AD, with the most pronounced differences emerging in aging. Finally, there was widespread upregulation of genes reflecting activation of microglia and perivascular macrophages in the aging brain, coupled with a downregulation of select factors (TOLLIP, fractalkine) that when present curtail microglial/macrophage activation. Notably, essentially all pathways of the innate immune system were upregulated in aging, including numerous complement components, genes involved in toll-like receptor signaling and inflammasome signaling, as well as genes coding for immunoglobulin (Fc) receptors and human leukocyte antigens I and II. Conclusions Unexpectedly, the extent of innate immune gene upregulation in AD was modest relative to the robust response apparent in the aged brain, consistent with the emerging idea of a critical involvement of inflammation in the earliest stages, perhaps even in the preclinical stage, of AD. Ultimately, our data suggest that an important strategy to maintain cognitive health and resilience involves reducing chronic innate immune activation that should be initiated in late midlife.
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Affiliation(s)
- David H Cribbs
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, 1226 Gillespie NRF, Irvine, CA 92697, USA.
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296
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The neuroprotective effects of milk fat globule-EGF factor 8 against oligomeric amyloid β toxicity. J Neuroinflammation 2012; 9:148. [PMID: 22742657 PMCID: PMC3418568 DOI: 10.1186/1742-2094-9-148] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 05/01/2012] [Indexed: 12/25/2022] Open
Abstract
Background Phosphatidylserine receptor is a key molecule that mediates the phagocytosis of apoptotic cells. Milk fat globule-EGF factor 8 (MFG-E8) is a phosphatidylserine receptor that is expressed on various macrophage lineage cells, including microglia in the central nervous system (CNS). Targeted clearance of degenerated neurons by microglia is essential to maintain healthy neural networks. We previously showed that the CX3C chemokine fractalkine is secreted from degenerated neurons and accelerates microglial clearance of neuronal debris via inducing the release of MFG-E8. However, the mechanisms by which microglia produce MFG-E8 and the precise functions of MFG-E8 are unknown. Methods The release of MFG-E8 from microglia treated with conditioned medium from neurons exposed to neurotoxic substances, glutamate or oligomeric amyloid β (oAβ) was measured by ELISA. The neuroprotective effects of MFG-E8 and MFG-E8 − induced microglial phagocytosis of oAβ were assessed by immunocytochemistry. The effects of MFG-E8 on the production of the anti-oxidative enzyme hemeoxygenase-1 (HO-1) were determined by ELISA and immunocytochemisty. Results MFG-E8 was induced in microglia treated with conditioned medium from neurons that had been exposed to neurotoxicants, glutamate or oAβ. MFG-E8 significantly attenuated oAβ-induced neuronal cell death in a primary neuron − microglia coculture system. Microglial phagocytosis of oAβ was accelerated by MFG-E8 treatment due to increased CD47 expression in the absence of neurotoxic molecule production, such as tumor necrosis factor-α, nitric oxide, and glutamate. MFG-E8 − treated microglia induced nuclear factor E(2) − related factor 2 (Nrf2) − mediated HO-1 production, which also contributed to neuroprotection. Conclusions These results suggest that microglia release MFG-E8 in response to signals from degenerated neurons and that MFG-E8 protects oAβ-induced neuronal cell death by promoting microglial phagocytic activity and activating the Nrf2-HO-1 pathway. Thus, MFG-E8 may have novel roles as a neuroprotectant in neurodegenerative conditions.
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297
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Effects of triptolide on the synaptophysin expression of hippocampal neurons in the AD cellular model. Int Immunopharmacol 2012; 13:175-80. [DOI: 10.1016/j.intimp.2012.03.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Revised: 03/10/2012] [Accepted: 03/21/2012] [Indexed: 11/22/2022]
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298
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Neuroprotective effect of the aminoestrogen prolame against impairment of learning and memory skills in rats injected with amyloid-β-25–35 into the hippocampus. Eur J Pharmacol 2012; 685:74-80. [DOI: 10.1016/j.ejphar.2012.04.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Revised: 03/23/2012] [Accepted: 04/05/2012] [Indexed: 01/26/2023]
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299
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Luo XG, Chen SD. The changing phenotype of microglia from homeostasis to disease. Transl Neurodegener 2012; 1:9. [PMID: 23210447 PMCID: PMC3514090 DOI: 10.1186/2047-9158-1-9] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Accepted: 04/24/2012] [Indexed: 12/20/2022] Open
Abstract
It has been nearly a century since the early description of microglia by Rio-Hortega; since then many more biological and pathological features of microglia have been recognized. Today, microglia are generally considered to be beneficial to homeostasis at the resting state through their abilities to survey the environment and phagocytose debris. However, when activated microglia assume diverse phenotypes ranging from fully inflamed, which involves the release of many pro-inflammatory cytokines, to alternatively activated, releasing anti-inflammatory cytokines or neurotrophins, the consequences to neurons can range from detrimental to supportive. Due to the different experimental sets and conditions, contradictory results have been obtained regarding the controversial question of whether microglia are “good” or “bad.” While it is well understood that the dual roles of activated microglia depend on specific situations, the underlying mechanisms have remained largely unclear, and the interpretation of certain findings related to diverse microglial phenotypes continues to be problematic. In this review we discuss the functions of microglia in neuronal survival and neurogenesis, the crosstalk between microglia and surrounding cells, and the potential factors that could influence the eventual manifestation of microglia.
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Affiliation(s)
- Xiao-Guang Luo
- Department of Neurology & Institute of Neurology, Ruijin Hospital affiliated to Shanghai Jiao Tong University, Shanghai, 200025, China.
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300
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Genc S, Zadeoglulari Z, Fuss SH, Genc K. The adverse effects of air pollution on the nervous system. J Toxicol 2012; 2012:782462. [PMID: 22523490 PMCID: PMC3317189 DOI: 10.1155/2012/782462] [Citation(s) in RCA: 355] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Accepted: 11/15/2011] [Indexed: 12/20/2022] Open
Abstract
Exposure to ambient air pollution is a serious and common public health concern associated with growing morbidity and mortality worldwide. In the last decades, the adverse effects of air pollution on the pulmonary and cardiovascular systems have been well established in a series of major epidemiological and observational studies. In the recent past, air pollution has also been associated with diseases of the central nervous system (CNS), including stroke, Alzheimer's disease, Parkinson's disease, and neurodevelopmental disorders. It has been demonstrated that various components of air pollution, such as nanosized particles, can easily translocate to the CNS where they can activate innate immune responses. Furthermore, systemic inflammation arising from the pulmonary or cardiovascular system can affect CNS health. Despite intense studies on the health effects of ambient air pollution, the underlying molecular mechanisms of susceptibility and disease remain largely elusive. However, emerging evidence suggests that air pollution-induced neuroinflammation, oxidative stress, microglial activation, cerebrovascular dysfunction, and alterations in the blood-brain barrier contribute to CNS pathology. A better understanding of the mediators and mechanisms will enable the development of new strategies to protect individuals at risk and to reduce detrimental effects of air pollution on the nervous system and mental health.
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Affiliation(s)
- Sermin Genc
- Department of Neuroscience, Health Science Institute, Dokuz Eylul University, Inciralti, 35340 Izmir, Turkey
| | - Zeynep Zadeoglulari
- Department of Neuroscience, Health Science Institute, Dokuz Eylul University, Inciralti, 35340 Izmir, Turkey
| | - Stefan H. Fuss
- Department of Molecular Biology and Genetics, Bogazici University, 34342 Istanbul, Turkey
| | - Kursad Genc
- Department of Neuroscience, Health Science Institute, Dokuz Eylul University, Inciralti, 35340 Izmir, Turkey
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