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Bilkei-Gorzo A. The endocannabinoid system in normal and pathological brain ageing. Philos Trans R Soc Lond B Biol Sci 2013; 367:3326-41. [PMID: 23108550 DOI: 10.1098/rstb.2011.0388] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The role of endocannabinoids as inhibitory retrograde transmitters is now widely known and intensively studied. However, endocannabinoids also influence neuronal activity by exerting neuroprotective effects and regulating glial responses. This review centres around this less-studied area, focusing on the cellular and molecular mechanisms underlying the protective effect of the cannabinoid system in brain ageing. The progression of ageing is largely determined by the balance between detrimental, pro-ageing, largely stochastic processes, and the activity of the homeostatic defence system. Experimental evidence suggests that the cannabinoid system is part of the latter system. Cannabinoids as regulators of mitochondrial activity, as anti-oxidants and as modulators of clearance processes protect neurons on the molecular level. On the cellular level, the cannabinoid system regulates the expression of brain-derived neurotrophic factor and neurogenesis. Neuroinflammatory processes contributing to the progression of normal brain ageing and to the pathogenesis of neurodegenerative diseases are suppressed by cannabinoids, suggesting that they may also influence the ageing process on the system level. In good agreement with the hypothesized beneficial role of cannabinoid system activity against brain ageing, it was shown that animals lacking CB1 receptors show early onset of learning deficits associated with age-related histological and molecular changes. In preclinical models of neurodegenerative disorders, cannabinoids show beneficial effects, but the clinical evidence regarding their efficacy as therapeutic tools is either inconclusive or still missing.
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Park SH, Lee S, Hong YK, Hwang S, Lee JH, Bang SM, Kim YK, Koo BS, Lee IS, Cho KS. Suppressive Effects of SuHeXiang Wan on Amyloid-β42-Induced Extracellular Signal-Regulated Kinase Hyperactivation and Glial Cell Proliferation in a Transgenic Drosophila Model of Alzheimer’s Disease. Biol Pharm Bull 2013; 36:390-8. [DOI: 10.1248/bpb.b12-00792] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | - Soojin Lee
- Department of Biological Sciences, Konkuk University
| | - Yoon Ki Hong
- Department of Biological Sciences, Konkuk University
| | - Soojin Hwang
- Department of Biological Sciences, Konkuk University
| | - Jang Ho Lee
- Department of Biological Sciences, Konkuk University
| | - Se Min Bang
- Department of Biological Sciences, Konkuk University
| | - Young-Kyoon Kim
- Department of Forest Products & Biotechnology, Kookmin University
| | - Byung-Soo Koo
- Department of Neuropsychiatry, Graduate School of Oriental Medicine, Dongguk University
| | - Im-Soon Lee
- Department of Biological Sciences, Konkuk University
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53
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Ashabi G, Ramin M, Azizi P, Taslimi Z, Alamdary SZ, Haghparast A, Ansari N, Motamedi F, Khodagholi F. ERK and p38 inhibitors attenuate memory deficits and increase CREB phosphorylation and PGC-1α levels in Aβ-injected rats. Behav Brain Res 2012; 232:165-73. [DOI: 10.1016/j.bbr.2012.04.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 03/30/2012] [Accepted: 04/03/2012] [Indexed: 11/30/2022]
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54
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Capsoni S, Marinelli S, Ceci M, Vignone D, Amato G, Malerba F, Paoletti F, Meli G, Viegi A, Pavone F, Cattaneo A. Intranasal "painless" human Nerve Growth Factor [corrected] slows amyloid neurodegeneration and prevents memory deficits in App X PS1 mice. PLoS One 2012; 7:e37555. [PMID: 22666365 PMCID: PMC3364340 DOI: 10.1371/journal.pone.0037555] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 04/25/2012] [Indexed: 02/02/2023] Open
Abstract
Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease (AD) treatment but the clinical application is hindered by its potent pro-nociceptive activity. Thus, to reduce systemic exposure that would induce pain, in recent clinical studies NGF was administered through an invasive intracerebral gene-therapy approach. Our group demonstrated the feasibility of a non-invasive intranasal delivery of NGF in a mouse model of neurodegeneration. NGF therapeutic window could be further increased if its nociceptive effects could be avoided altogether. In this study we exploit forms of NGF, mutated at residue R100, inspired by the human genetic disease HSAN V (Hereditary Sensory Autonomic Neuropathy Type V), which would allow increasing the dose of NGF without triggering pain. We show that "painless" hNGF displays full neurotrophic and anti-amyloidogenic activities in neuronal cultures, and a reduced nociceptive activity in vivo. When administered intranasally to APPxPS1 mice ( n = 8), hNGFP61S/R100E prevents the progress of neurodegeneration and of behavioral deficits. These results demonstrate the in vivo neuroprotective and anti-amyloidogenic properties of hNGFR100 mutants and provide a rational basis for the development of "painless" hNGF variants as a new generation of therapeutics for neurodegenerative diseases.
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Affiliation(s)
- Simona Capsoni
- European Brain Research Institute, Rome, Italy
- Scuola Normale Superiore, Pisa, Italy
| | - Sara Marinelli
- Institute of Neuroscience, Consiglio Nazionale delle Ricerche, Rome, Italy
| | | | | | | | - Francesca Malerba
- European Brain Research Institute, Rome, Italy
- Scuola Normale Superiore, Pisa, Italy
| | | | | | | | - Flaminia Pavone
- Institute of Neuroscience, Consiglio Nazionale delle Ricerche, Rome, Italy
| | - Antonino Cattaneo
- European Brain Research Institute, Rome, Italy
- Scuola Normale Superiore, Pisa, Italy
- * E-mail:
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55
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Han X, Ma Y, Liu X, Wang L, Qi S, Zhang Q, Du Y. Changes in insulin-signaling transduction pathway underlie learning/memory deficits in an Alzheimer’s disease rat model. J Neural Transm (Vienna) 2012; 119:1407-16. [DOI: 10.1007/s00702-012-0803-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 03/29/2012] [Indexed: 12/20/2022]
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Abstract
The buildup of Abeta and tau is believed to directly cause or contribute to the progressive cognitive deficits characteristic of Alzheimer disease. However, the molecular pathways linking Abeta and tau accumulation to learning and memory deficits remain elusive. There is growing evidence that soluble forms of Abeta and tau can obstruct learning and memory by interfering with several signaling cascades. In this review, I will present data showing that the mammalian target of rapamycin (mTOR) may play a role in Abeta and tau induced neurodegeneration.
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Affiliation(s)
- Salvatore Oddo
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA.
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58
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Scott Bitner R. Cyclic AMP response element-binding protein (CREB) phosphorylation: a mechanistic marker in the development of memory enhancing Alzheimer's disease therapeutics. Biochem Pharmacol 2011; 83:705-14. [PMID: 22119240 DOI: 10.1016/j.bcp.2011.11.009] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 11/07/2011] [Accepted: 11/09/2011] [Indexed: 10/15/2022]
Abstract
CREB-mediated transcription can be initiated by membrane receptor stimulation and subsequent activation of intracellular pathways to the cell nucleus, and has been described as a molecular switch required for learning and memory. While CREB dimers are thought to be constitutively bound to response elements on DNA under basal conditions, it is CREB phosphorylation that is believed to be responsible for transcriptional activation leading to gene products such as BDNF that play a key role in synaptic plasticity and cognitive function. Conversely, preclinical and clinical findings now suggest that impaired CREB phosphorylation may be a pathological component in neurodegenerative disorders, in particular Alzheimer's disease (AD). In this regard, pharmacological-induced CREB phosphorylation in brain regions associated with cognition, i.e. cortex and hippocampus may represent a mechanistic basis for the development of novel AD therapeutics. The purpose of this commentary is to describe an experimental strategy to biochemically characterize the pharmacological induction of CREB phosphorylation as a mechanistic marker across different pharmacological classes of compounds for the potential treatment of AD that include: α7 nicotinic agonists, H3 antagonists and 11β HSD1 inhibitors.
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Affiliation(s)
- R Scott Bitner
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, IL 60064, United States.
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59
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Ljungberg MC, Ali YO, Zhu J, Wu CS, Oka K, Zhai RG, Lu HC. CREB-activity and nmnat2 transcription are down-regulated prior to neurodegeneration, while NMNAT2 over-expression is neuroprotective, in a mouse model of human tauopathy. Hum Mol Genet 2011; 21:251-67. [PMID: 22027994 DOI: 10.1093/hmg/ddr492] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Tauopathies, characterized by neurofibrillary tangles (NFTs) of phosphorylated tau proteins, are a group of neurodegenerative diseases, including frontotemporal dementia and both sporadic and familial Alzheimer's disease. Forebrain-specific over-expression of human tau(P301L), a mutation associated with frontotemporal dementia with parkinsonism linked to chromosome 17, in rTg4510 mice results in the formation of NFTs, learning and memory impairment and massive neuronal death. Here, we show that the mRNA and protein levels of NMNAT2 (nicotinamide mononucleotide adenylyltransferase 2), a recently identified survival factor for maintaining neuronal health in peripheral nerves, are reduced in rTg4510 mice prior to the onset of neurodegeneration or cognitive deficits. Two functional cAMP-response elements (CREs) were identified in the nmnat2 promoter region. Both the total amount of phospho-CRE binding protein (CREB) and the pCREB bound to nmnat2 CRE sites in the cortex and the hippocampus of rTg4510 mice are significantly reduced, suggesting that NMNAT2 is a direct target of CREB under physiological conditions and that tau(P301L) overexpression down-regulates CREB-mediated transcription. We found that over-expressing NMNAT2 or its homolog NMNAT1, but not NMNAT3, in rTg4510 hippocampi from 6 weeks of age using recombinant adeno-associated viral vectors significantly reduced neurodegeneration caused by tau(P301L) over-expression at 5 months of age. In summary, our studies strongly support a protective role of NMNAT2 in the mammalian central nervous system. Decreased endogenous NMNAT2 function caused by reduced CREB signaling during pathological insults may be one of underlying mechanisms for neuronal death in tauopathies.
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Affiliation(s)
- M Cecilia Ljungberg
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
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60
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Zeitlin R, Patel S, Burgess S, Arendash GW, Echeverria V. Caffeine induces beneficial changes in PKA signaling and JNK and ERK activities in the striatum and cortex of Alzheimer's transgenic mice. Brain Res 2011; 1417:127-36. [PMID: 21907331 DOI: 10.1016/j.brainres.2011.08.036] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 07/26/2011] [Accepted: 08/14/2011] [Indexed: 02/07/2023]
Abstract
Caffeine intake has been associated with a lower incidence of Alzheimer's disease (AD) in humans. In AD mouse models, caffeine significantly decreases senile plaques and amyloid beta (Aβ) levels while also protecting against or reversing cognitive impairment. To understand the mechanism(s) underlying the protective effects of caffeine against AD pathology, we investigated the effects of a two-week treatment with caffeine (3mg/day) in transgenic (APPswe) mice and non-transgenic (NT) mice on signaling factors involved in neuronal plasticity and survival. We evaluated cAMP-dependent protein kinase A (PKA), phospho-cyclic AMP response-element binding protein (phospho-CREB), and the pro-apoptotic protein kinases extracellular signal-regulated kinase 1/2 (phospho-ERK) and phospho-c-Jun N-terminal kinase 1 (phospho-JNK) in the striatum and frontal cortex of caffeine-treated mice. In the striatum, APPswe control mice exhibited a significant decrease in phospho-CREB, as well as significant increases in phospho-JNK and phospho-ERK in comparison to NT mice. Caffeine treatment stimulated PKA activity, increased phospho-CREB levels, and decreased phospho-JNK and phospho-ERK expression in the striatum of APPswe mice, all of which are thought to be beneficial changes for brain function. Even caffeine-treated NT mice exhibited some of these changes in striatum. In the frontal cortex, caffeine did not significantly increase phospho-CREB and PKA activity, but significantly reduced phospho-JNK and phospho-ERK expression in both APPswe and NT mice. These results suggest that caffeine shifts the balance between neurodegeneration and neuronal survival toward the stimulation of pro-survival cascades and inhibition of pro-apoptotic pathways in the striatum and/or cortex, which may contribute to its beneficial effects against AD.
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Affiliation(s)
- Ross Zeitlin
- Research and Development, Department of Veterans Affairs, Bay Pines VA Healthcare System, Bay Pines, FL 33744, USA
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61
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Müller M, Cárdenas C, Mei L, Cheung KH, Foskett JK. Constitutive cAMP response element binding protein (CREB) activation by Alzheimer's disease presenilin-driven inositol trisphosphate receptor (InsP3R) Ca2+ signaling. Proc Natl Acad Sci U S A 2011; 108:13293-8. [PMID: 21784978 PMCID: PMC3156223 DOI: 10.1073/pnas.1109297108] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Mutations in presenilins (PS) account for most early-onset familial Alzheimer's disease (FAD). Accumulating evidence suggests that disrupted Ca(2+) signaling may play a proximal role in FAD specifically, and Alzheimer's disease (AD) more generally, but its links to the pathogenesis of AD are obscure. Here we demonstrate that expression of FAD mutant PS constitutively activates the transcription factor cAMP response element binding protein (CREB) and CREB target gene expression in cultured neuronal cells and AD mouse models. Constitutive CREB activation was associated with and dependent on constitutive activation of Ca(2+)/CaM kinase kinase β and CaM kinase IV (CaMKIV). Depletion of endoplasmic reticulum Ca(2+) stores or plasma membrane phosphatidylinositol-bisphosphate and pharmacologic inhibition or knockdown of the expression of the inositol trisphosphate receptor (InsP(3)R) Ca(2+) release channel each abolished FAD PS-associated constitutive CaMKIV and CREB phosphorylation. CREB and CaMKIV phosphorylation and CREB target gene expression, including nitric oxide synthase and c-fos, were enhanced in brains of M146V-KI and 3xTg-AD mice expressing FAD mutant PS1 knocked into the mouse locus. FAD mutant PS-expressing cells demonstrated enhanced cell death and sensitivity to Aβ toxicity, which were normalized by interfering with the InsP(3)R-CAMKIV-CREB pathway. Thus, constitutive CREB phosphorylation by exaggerated InsP(3)R Ca(2+) signaling in FAD PS-expressing cells may represent a signaling pathway involved in the pathogenesis of AD.
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Affiliation(s)
| | | | | | | | - J. Kevin Foskett
- Departments of Physiology and
- Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
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62
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Caetano FA, Beraldo FH, Hajj GNM, Guimaraes AL, Jürgensen S, Wasilewska-Sampaio AP, Hirata PHF, Souza I, Machado CF, Wong DYL, De Felice FG, Ferreira ST, Prado VF, Rylett RJ, Martins VR, Prado MAM. Amyloid-beta oligomers increase the localization of prion protein at the cell surface. J Neurochem 2011; 117:538-53. [PMID: 21352228 DOI: 10.1111/j.1471-4159.2011.07225.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
In Alzheimer's disease, the amyloid-β peptide (Aβ) interacts with distinct proteins at the cell surface to interfere with synaptic communication. Recent data have implicated the prion protein (PrP(C)) as a putative receptor for Aβ. We show here that Aβ oligomers signal in cells in a PrP(C)-dependent manner, as might be expected if Aβ oligomers use PrP(C) as a receptor. Immunofluorescence, flow cytometry and cell surface protein biotinylation experiments indicated that treatment with Aβ oligomers, but not monomers, increased the localization of PrP(C) at the cell surface in cell lines. These results were reproduced in hippocampal neuronal cultures by labeling cell surface PrP(C). In order to understand possible mechanisms involved with this effect of Aβ oligomers, we used live cell confocal and total internal reflection microscopy in cell lines. Aβ oligomers inhibited the constitutive endocytosis of PrP(C), but we also found that after Aβ oligomer-treatment PrP(C) formed more clusters at the cell surface, suggesting the possibility of multiple effects of Aβ oligomers. Our experiments show for the first time that Aβ oligomers signal in a PrP(C)-dependent way and that they can affect PrP(C) trafficking, increasing its localization at the cell surface.
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Affiliation(s)
- Fabiana A Caetano
- J. Allyn Taylor Centre for Cell Biology, Robarts Research Institute, University of Western Ontario, London, Ontario, Canada
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63
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Bitner RS, Markosyan S, Nikkel AL, Brioni JD. In-vivo histamine H3 receptor antagonism activates cellular signaling suggestive of symptomatic and disease modifying efficacy in Alzheimer’s disease. Neuropharmacology 2011; 60:460-6. [DOI: 10.1016/j.neuropharm.2010.10.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 10/21/2010] [Accepted: 10/25/2010] [Indexed: 11/30/2022]
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64
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Saura CA, Valero J. The role of CREB signaling in Alzheimer’s disease and other cognitive disorders. Rev Neurosci 2011; 22:153-69. [DOI: 10.1515/rns.2011.018] [Citation(s) in RCA: 201] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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65
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Bekris LM, Galloway NM, Millard S, Lockhart D, Li G, Galasko DR, Farlow MR, Clark CM, Quinn JF, Kaye JA, Schellenberg GD, Leverenz JB, Seubert P, Tsuang DW, Peskind ER, Yu CE. Amyloid precursor protein (APP) processing genes and cerebrospinal fluid APP cleavage product levels in Alzheimer's disease. Neurobiol Aging 2010; 32:556.e13-23. [PMID: 21196064 DOI: 10.1016/j.neurobiolaging.2010.10.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 10/27/2010] [Accepted: 10/28/2010] [Indexed: 12/22/2022]
Abstract
The aim of this exploratory investigation was to determine if genetic variation within amyloid precursor protein (APP) or its processing enzymes correlates with APP cleavage product levels: APPα, APPβ or Aβ42, in cerebrospinal fluid (CSF) of cognitively normal subjects or Alzheimer's disease (AD) patients. Cognitively normal control subjects (n = 170) and AD patients (n = 92) were genotyped for 19 putative regulatory tagging SNPs within 9 genes (APP, ADAM10, BACE1, BACE2, PSEN1, PSEN2, PEN2, NCSTN and APH1B) involved in the APP processing pathway. SNP genotypes were tested for their association with CSF APPα, APPβ, and Aβ42, AD risk and age-at-onset while taking into account age, gender, race and APOE ε4. After adjusting for multiple comparisons, a significant association was found between ADAM10 SNP rs514049 and APPα levels. In controls, the rs514049 CC genotype had higher APPα levels than the CA, AA collapsed genotype, whereas the opposite effect was seen in AD patients. These results suggest that genetic variation within ADAM10, an APP processing gene, influences CSF APPα levels in an AD specific manner.
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Affiliation(s)
- L M Bekris
- Geriatric Research, Education and Clinical Center (GRECC), VA Puget Sound Health Care System, Seattle, WA, USA.
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66
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CBP gene transfer increases BDNF levels and ameliorates learning and memory deficits in a mouse model of Alzheimer's disease. Proc Natl Acad Sci U S A 2010; 107:22687-92. [PMID: 21149712 DOI: 10.1073/pnas.1012851108] [Citation(s) in RCA: 182] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cognitive dysfunction and memory loss are common features of Alzheimer's disease (AD). Abnormalities in the expression profile of immediate early genes that play a critical role in memory formation, such as the cAMP-response element binding protein (CREB), have been reported in the brains of AD patients. Here we show that amyloid-β (Aβ) accumulation, which plays a primary role in the cognitive deficits of AD, interferes with CREB activity. We further show that restoring CREB function via brain viral delivery of the CREB-binding protein (CBP) improves learning and memory deficits in an animal model of AD. Notably, such improvements occur without changes in Aβ and tau pathology, and instead are linked to an increased level of brain-derived neurotrophic factor. The resulting data suggest that Aβ-induced learning and memory deficits are mediated by alterations in CREB function, based on the finding that restoring CREB activity by directly modulating CBP levels in the brains of adult mice is sufficient to ameliorate learning and memory. Therefore, increasing CBP expression in adult brains may be a valid therapeutic approach not only for AD, but also for various brain disorders characterized by alterations in immediate early genes, further supporting the concept that viral vector delivery may be a viable therapeutic approach in neurodegenerative diseases.
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67
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Sakamoto K, Karelina K, Obrietan K. CREB: a multifaceted regulator of neuronal plasticity and protection. J Neurochem 2010; 116:1-9. [PMID: 21044077 DOI: 10.1111/j.1471-4159.2010.07080.x] [Citation(s) in RCA: 353] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Since its initial characterization over 20 years ago, there has been intense and unwavering interest in understanding the role of the transcription factor cAMP-responsive element binding protein (CREB) in nervous system physiology. Through an array of experimental approaches and model systems, researchers have begun to unravel the complex and multifaceted role of this transcription factor in such diverse processes as neurodevelopment, synaptic plasticity, and neuroprotection. Here we discuss current insights into the molecular mechanisms by which CREB couples synaptic activity to long-term changes in neuronal plasticity, which is thought to underlie learning and memory. We also discuss work showing that CREB is a critical component of the neuroprotective transcriptional network, and data indicating that CREB dysregulation contributes to an array of neuropathological conditions.
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Affiliation(s)
- Kensuke Sakamoto
- Department of Neuroscience, Ohio State University, Columbus, Ohio 43210, USA
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68
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Liang B, Duan BY, Zhou XP, Gong JX, Luo ZG. Calpain activation promotes BACE1 expression, amyloid precursor protein processing, and amyloid plaque formation in a transgenic mouse model of Alzheimer disease. J Biol Chem 2010; 285:27737-44. [PMID: 20595388 PMCID: PMC2934641 DOI: 10.1074/jbc.m110.117960] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 06/27/2010] [Indexed: 12/17/2022] Open
Abstract
Abnormal activation of calpain is implicated in synaptic dysfunction and participates in neuronal death in Alzheimer disease (AD) and other neurological disorders. Pharmacological inhibition of calpain has been shown to improve memory and synaptic transmission in the mouse model of AD. However, the role and mechanism of calpain in AD progression remain elusive. Here we demonstrate a role of calpain in the neuropathology in amyloid precursor protein (APP) and presenilin 1 (PS1) double-transgenic mice, an established mouse model of AD. We found that overexpression of endogenous calpain inhibitor calpastatin (CAST) under the control of the calcium/calmodulin-dependent protein kinase II promoter in APP/PS1 mice caused a remarkable decrease of amyloid plaque burdens and prevented Tau phosphorylation and the loss of synapses. Furthermore, CAST overexpression prevented the decrease in the phosphorylation of the memory-related molecules CREB and ERK in the brain of APP/PS1 mice and improved spatial learning and memory. Interestingly, treatment of cultured primary neurons with amyloid-beta (Abeta) peptides caused an increase in the level of beta-site APP-cleaving enzyme 1 (BACE1), the key enzyme responsible for APP processing and Abeta production. This effect was inhibited by CAST overexpression. Consistently, overexpression of calpain in heterologous APP expressing cells up-regulated the level of BACE1 and increased Abeta production. Finally, CAST transgene prevented the increase of BACE1 in APP/PS1 mice. Thus, calpain activation plays an important role in APP processing and plaque formation, probably by regulating the expression of BACE1.
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Affiliation(s)
- Bin Liang
- From the Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Bao-Yu Duan
- From the Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xiu-Ping Zhou
- From the Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jia-Xin Gong
- From the Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhen-Ge Luo
- From the Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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Seo JS, Jung EY, Kim JH, Lyu YS, Han PL, Kang HW. A modified preparation (LMK03) of the oriental medicine Jangwonhwan reduces Abeta(1-42) level in the brain of Tg-APPswe/PS1dE9 mouse model of Alzheimer disease. JOURNAL OF ETHNOPHARMACOLOGY 2010; 130:578-585. [PMID: 20669372 DOI: 10.1016/j.jep.2010.05.055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The oriental medicine Jangwonhwan, which is a boiled extract of 12 medicinal herbs/mushroom, has been prescribed for patients with cognitive dysfunction. Recently, a modified recipe of Jangwonhwan (LMK02-Jangwonhwan) consisting of seven medicinal plants/mushroom, was shown to have a therapeutic potential to ameliorate AD-like pathology. AIM OF THE STUDY It was investigated whether a further reduction of Jangwonhwan (LMK03-Jangwonhwan) retains the potency to suppress the AD-like pathology. MATERIALS AND METHODS The transgenic mice of Alzheimer disease, Tg-APPswe/PS1dE9, were fed LMK03-Jangwonhwan consisting of two of the herbs, white Poria cocos (Schw.) Wolf and Angelica gigas Nakai, which could protect the AD-like pathology at 300 mg/kg/day of dose for 3 months. In vitro cell biological study, immunohistological and ELISA (enzyme-linked immunosorbent assay) analyses were used to assess its neuroprotective effects against Abeta-induced cell death, and the Abeta accumulation and plaque deposition in the brain. RESULTS In vitro study with SH-SY5Y neuroblastoma cells showed that LMK03-Jangwonhwan could protect from cytotoxicity induced by hydrogen peroxide or oligomeric Abeta(1-42). Tg-APPswe/PS1dE9 mice were administered LMK03-Jangwonhwan at 300 mg/kg/day for 3 months from 4.5 months of age. Immunohistological and ELISA analyses showed that LMK03-Jangwonhwan partially reduced Abeta(1-42)and Abeta(1-40) levels and beta-amyloid plaque deposition in the brain of Tg-APPswe/PS1dE9 mice. However, LMK03-Jangwonhwan poorly suppressed accumulation of reactive oxidative stress in the hippocampus of Tg-APPswe/PS1dE9 mice and inefficiently improved the expression of phospho-CREB and calbindin, the cellular factors that were down-regulated in AD-like brains. CONCLUSIONS These results suggest that LMK03-Jangwonhwan has a potency to inhibit AD-like pathology at a detectable level, but LMK03 is not likely to retain the major ability of LMK02-Jangwonhwan to modify AD pathology in several AD-related molecular parameters.
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Affiliation(s)
- Ji-Seon Seo
- Department of Chemistry & Nano Science, Ewha Womans University, Seoul, Republic of Korea
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beta-Amyloid disrupts activity-dependent gene transcription required for memory through the CREB coactivator CRTC1. J Neurosci 2010; 30:9402-10. [PMID: 20631169 DOI: 10.1523/jneurosci.2154-10.2010] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Activity-dependent gene expression mediating changes of synaptic efficacy is important for memory storage, but the mechanisms underlying gene transcriptional changes in age-related memory disorders are poorly understood. In this study, we report that gene transcription mediated by the cAMP-response element binding protein (CREB)-regulated transcription coactivator CRTC1 is impaired in neurons and brain from an Alzheimer's disease (AD) transgenic mouse expressing the human beta-amyloid precursor protein (APP(Sw,Ind)). Suppression of CRTC1-dependent gene transcription by beta-amyloid (Abeta) in response to cAMP and Ca(2+) signals is mediated by reduced calcium influx and disruption of PP2B/calcineurin-dependent CRTC1 dephosphorylation at Ser151. Consistently, expression of CRTC1 or active CRTC1 S151A and calcineurin mutants reverse the deficits on CRTC1 transcriptional activity in APP(Sw,Ind) neurons. Inhibition of calcium influx by pharmacological blockade of L-type voltage-gated calcium channels (VGCCs), but not by blocking NMDA or AMPA receptors, mimics the decrease on CRTC1 transcriptional activity observed in APP(Sw,Ind) neurons, whereas agonists of L-type VGCCs reverse efficiently these deficits. Consistent with a role of CRTC1 on Abeta-induced synaptic and memory dysfunction, we demonstrate a selective reduction of CRTC1-dependent genes related to memory (Bdnf, c-fos, and Nr4a2) coinciding with hippocampal-dependent spatial memory deficits in APP(Sw,Ind) mice. These findings suggest that CRTC1 plays a key role in coupling synaptic activity to gene transcription required for hippocampal-dependent memory, and that Abeta could disrupt cognition by affecting CRTC1 function.
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71
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Alkam T, Nitta A, Furukawa-Hibi Y, Niwa M, Mizoguchi H, Yamada K, Nabeshima T. Oral supplementation with Leu-Ile, a hydrophobic dipeptide, prevents the impairment of memory induced by amyloid beta in mice via restraining the hyperphosphorylation of extracellular signal-regulated kinase. Behav Brain Res 2010; 210:184-90. [DOI: 10.1016/j.bbr.2010.02.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2009] [Revised: 02/06/2010] [Accepted: 02/12/2010] [Indexed: 11/25/2022]
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72
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Crews L, Masliah E. Molecular mechanisms of neurodegeneration in Alzheimer's disease. Hum Mol Genet 2010; 19:R12-20. [PMID: 20413653 PMCID: PMC2875049 DOI: 10.1093/hmg/ddq160] [Citation(s) in RCA: 475] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 04/19/2010] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by cognitive impairment, progressive neurodegeneration and formation of amyloid-beta (Abeta)-containing plaques and neurofibrillary tangles composed of hyperphosphorylated tau. The neurodegenerative process in AD is initially characterized by synaptic damage accompanied by neuronal loss. In addition, recent evidence suggests that alterations in adult neurogenesis in the hippocampus might play a role. Synaptic loss is one of the strongest correlates to the cognitive impairment in patients with AD. Several lines of investigation support the notion that the synaptic pathology and defective neurogenesis in AD are related to progressive accumulation of Abeta oligomers rather than fibrils. Abnormal accumulation of Abeta resulting in the formation of toxic oligomers is the result of an imbalance between the levels of Abeta production, aggregation and clearance. Abeta oligomers might lead to synaptic damage by forming pore-like structures with channel activity; alterations in glutamate receptors; circuitry hyper-excitability; mitochondrial dysfunction; lysosomal failure and alterations in signaling pathways related to synaptic plasticity, neuronal cell and neurogenesis. A number of signaling proteins, including fyn kinase; glycogen synthase kinase-3beta (GSK3beta) and cyclin-dependent kinase-5 (CDK5), are involved in the neurodegenerative progression of AD. Therapies for AD might require the development of anti-aggregation compounds, pro-clearance pathways and blockers of hyperactive signaling pathways.
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Affiliation(s)
| | - Eliezer Masliah
- Department of Pathology and
- Department of Neurosciences, University of California – San Diego, 9500 Gilman Drive, La Jolla, CA 92003-0624, USA
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73
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Tran TT, Srivareerat M, Alkadhi KA. Chronic psychosocial stress accelerates impairment of long-term memory and late-phase long-term potentiation in an at-risk model of Alzheimer's disease. Hippocampus 2010; 21:724-32. [PMID: 20865724 DOI: 10.1002/hipo.20790] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2010] [Indexed: 01/05/2023]
Abstract
Although it is generally agreed that Aβ contributes to the pathogenesis of AD, its precise role in AD and the reason for the varying intensity and time of onset of the disease have not been elucidated. In addition to genetic factors, environmental issues such as stress may also play a critical role in the etiology of AD. This study examined the effect of chronic psychosocial stress in an at-risk (treatment with a subpathogenic dose of Aβ; "subAβ") rat model of AD on long-term memory by three techniques: memory tests in the radial arm water maze, electrophysiological recordings of synaptic plasticity in anesthetized rats, and immunoblot analysis of learning- and long-term memory-related signaling molecules. Chronic psychosocial stress was induced using a rat intruder model. The subAβ rat model of AD was induced by continuous infusion of 160 pmol/day Aβ(1-42) via a 14-day i.c.v. osmotic pump. All tests showed that subAβ rats were not different from control rats. Result from behavioral tests and electrophysiological recordings showed that infusion of subAβ in chronically stressed rats (stress/subAβ group) caused significant impairment of cognitive functions and late-phase long-term potentiation (L-LTP). Molecular analysis of various signaling molecules after expression of L-LTP, revealed an increase in the levels of p-CREB in control, stress, and subAβ rats, but not in the stress/subAβ rats. These findings suggest that the chronic stress-induced molecular alteration may accelerate the impairment of cognition and synaptic plasticity in individuals "at-risk" for AD.
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Affiliation(s)
- Trinh T Tran
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, College of Pharmacy, Texas
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74
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Young KF, Pasternak SH, Rylett RJ. Oligomeric aggregates of amyloid β peptide 1–42 activate ERK/MAPK in SH-SY5Y cells via the α7 nicotinic receptor. Neurochem Int 2009; 55:796-801. [DOI: 10.1016/j.neuint.2009.08.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Revised: 07/28/2009] [Accepted: 08/01/2009] [Indexed: 10/20/2022]
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75
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Brewer GJ, Torricelli JR, Lindsey AL, Kunz EZ, Neuman A, Fisher DR, Joseph JA. Age-related toxicity of amyloid-beta associated with increased pERK and pCREB in primary hippocampal neurons: reversal by blueberry extract. J Nutr Biochem 2009; 21:991-8. [PMID: 19954954 DOI: 10.1016/j.jnutbio.2009.08.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 08/14/2009] [Accepted: 08/20/2009] [Indexed: 01/19/2023]
Abstract
Further clarification is needed to address the paradox that memory formation, aging and neurodegeneration all involve calcium influx, oxyradical production (ROS) and activation of certain signaling pathways. In aged rats and in APP/PS-1 mice, cognitive and hippocampal Ca(2+) dysregulation was reversed by food supplementation with a high antioxidant blueberry extract. Here, we studied whether neurons were an important target of blueberry extract and whether the mechanism involved altered ROS signaling through MAP kinase and cyclic-AMP response element binding protein (CREB), pathways known to be activated in response to amyloid-beta (Aβ). Primary hippocampal neurons were isolated and cultured from embryonic, middle-age or old-age (24 months) rats. Blueberry extract was found to be equally neuroprotective against Aβ neurotoxicity at all ages. Increases in Aβ toxicity with age were associated with age-related increases in immunoreactivity of neurons to pERK and an age-independent increase in pCREB. Treatment with blueberry extract strongly inhibited these increases in parallel with neuroprotection. Simultaneous labeling for ROS and for glutathione with dichlorofluorescein and monochlorobimane showed a mechanism of action of blueberry extract to involve transient ROS generation with an increase in the redox buffer glutathione. We conclude that the increased age-related susceptibility of old-age neurons to Aβ toxicity may be due to higher levels of activation of pERK and pCREB pathways that can be protected by blueberry extract through inhibition of both these pathways through an ROS stress response. These results suggest that the beneficial effects of blueberry extract may involve transient stress signaling and ROS protection that may translate into improved cognition in aging rats and APP/PS1 mice given blueberry extract.
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Affiliation(s)
- Gregory J Brewer
- Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL 62794-9626, USA.
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76
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Failures to reconsolidate memory in a mouse model of Alzheimer's disease. Neurobiol Learn Mem 2009; 92:455-9. [PMID: 19435612 DOI: 10.1016/j.nlm.2009.05.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 04/25/2009] [Accepted: 05/05/2009] [Indexed: 11/21/2022]
Abstract
Previous studies have demonstrated that the formation of spatial, contextual and trace conditioning memories are impaired in animal models of Alzheimer's disease (AD), consistent with the observations that the first sign of cognitive decline in AD includes difficulties in the acquisition of new information or memory formation. Evidence is accumulating that memory retrieval is a dynamic process in which stored information becomes labile again and needs to be restabilized. However, it is poorly understood how this process referred to as memory reconsolidation is affected in animal models of AD. The present study was designed to use contextual fear conditioning to compare the changes in memory formation and subsequent reconsolidation processes in transgenic mice that overexpress human APP and PS1 harboring five familial AD mutations (5XFAD model). The results clearly demonstrate that cognitive dysfunction starts to occur primarily as reduced levels of contextual learning or memory formation in 5XFAD mice, but it is exacerbated by additional retrieval-dependent retrograde amnesia due to deficient reconsolidation as disease further develops.
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77
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Ma QL, Galasko DR, Ringman JM, Vinters HV, Edland SD, Pomakian J, Ubeda OJ, Rosario ER, Teter B, Frautschy SA, Cole GM. Reduction of SorLA/LR11, a sorting protein limiting beta-amyloid production, in Alzheimer disease cerebrospinal fluid. ACTA ACUST UNITED AC 2009; 66:448-57. [PMID: 19364929 DOI: 10.1001/archneurol.2009.22] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND The sortilin-related receptor SorLA/LR11 (LR11) is a transmembrane neuronal sorting protein that reduces beta-amyloid precursor protein trafficking to secretases, notably BACE1 that generates beta-amyloid, the principal component of senile plaques in Alzheimer disease (AD). LR11 protein is reduced in patients with late-onset AD, and LR11 polymorphisms have been associated with late-onset AD. OBJECTIVE T o detect soluble LR11 and APP in cerebrospinal fluid (CSF) from patients with AD and control subjects, as (like beta-amyloid precursor protein) LR11 is cleaved near the membrane to release a large N-terminal fragment that is secreted to media from cultured cells. DESIGN Case-control study. SETTING Academic research. PARTICIPANTS Patients with AD and control subjects. MAIN OUTCOME MEASURES We evaluated CSF LR11, beta-amyloid precursor protein, and apolipoprotein E levels by Western blot in lumbar and postmortem CSF samples. RESULTS LR11 levels were detectable and stable during 6 months in the CSF of patients with AD. LR11 levels were significantly reduced in lumbar samples from patients with mild to moderate probable AD, as well as in ventricular CSF from patients with autopsy-confirmed AD (predominantly Braak stage III-IV). Bivariate analysis with beta-amyloid 42 and LR11 levels improved diagnostic specificity for AD. Reduced LR11 levels are significantly correlated with soluble beta-amyloid precursor protein but not apolipoprotein E levels. CONCLUSION Reduced LR11 levels in CSF of patients with AD may have potential as a diagnostic biomarker for patients with LR11 deficits that promote beta-amyloid production or as an index of therapeutic response in late-onset AD.
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Affiliation(s)
- Qiu-Lan Ma
- Department of Medicine, University of California, Los Angeles, California, USA
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78
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Hu S, Begum AN, Jones MR, Oh MS, Beech WK, Beech BH, Yang F, Chen P, Ubeda OJ, Kim PC, Davies P, Ma Q, Cole GM, Frautschy SA. GSK3 inhibitors show benefits in an Alzheimer's disease (AD) model of neurodegeneration but adverse effects in control animals. Neurobiol Dis 2008; 33:193-206. [PMID: 19038340 DOI: 10.1016/j.nbd.2008.10.007] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Revised: 09/19/2008] [Accepted: 10/07/2008] [Indexed: 12/22/2022] Open
Abstract
The dysregulation of glycogen synthase kinase-3 (GSK3) has been implicated in Alzheimer disease (AD) pathogenesis and in Abeta-induced neurotoxicity, leading us to investigate it as a therapeutic target in an intracerebroventricular Abeta infusion model. Infusion of a specific GSK3 inhibitor SB216763 (SB) reduced a downstream target, phospho-glycogen synthase 39%, and increased glycogen levels 44%, suggesting effective inhibition of enzyme activity. Compared to vehicle, Abeta increased GSK3 activity, and was associated with elevations in levels of ptau, caspase-3, the tau kinase phospho-c-jun N-terminal kinase (pJNK), neuronal DNA fragmentation, and gliosis. Co-infusion of SB corrected all responses to Abeta infusion except the induction of gliosis and behavioral deficits in the Morris water maze. Nevertheless, SB alone was associated with induction of neurodegenerative markers and behavioral deficits. These data support a role for GSK3 hyperactivation in AD pathogenesis, but emphasize the importance of developing inhibitors that do not suppress constitutive activity.
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Affiliation(s)
- Shuxin Hu
- Greater Los Angeles Healthcare System, Geriatric Research Education and Clinical Center, Veteran's Affairs Medical Center, USA
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79
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Ischiropoulos H. Protein tyrosine nitration--an update. Arch Biochem Biophys 2008; 484:117-21. [PMID: 19007743 DOI: 10.1016/j.abb.2008.10.034] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Revised: 10/24/2008] [Accepted: 10/24/2008] [Indexed: 10/21/2022]
Abstract
Tyrosine nitration is a covalent post-translational protein modification derived from the reaction of proteins with nitrating agents. Tyrosine nitration has been used as a marker of oxidant burden in human diseases. However, it remains unclear whether protein nitration is responsible for alterations in protein function that imparts an increased risk for disease development or unfavorable outcomes. Emerging data implicate tyrosine nitration as a mediator of immune responses suggesting a novel biological function for this protein modification.
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Affiliation(s)
- Harry Ischiropoulos
- Stokes Research Institute and Departments of Pediatrics and Pharmacology, Children's Hospital of Philadelphia and The University of Pennsylvania, 417 Abramson Research Center, Philadelphia, PA 19104-4318, USA.
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80
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Abstract
In the genesis of Alzheimer's disease (AD), converging lines of evidence suggest that amyloid-beta peptide (Abeta) triggers a pathogenic cascade leading to neuronal loss. It was long assumed that Abeta had to be assembled into extracellular amyloid fibrils or aggregates to exert its cytotoxic effects. Over the past decade, characterization of soluble oligomeric Abeta species in the brains of AD patients and in transgenic models has raised the possibility that different conformations of Abeta may contribute to AD pathology via different mechanisms. The receptor for advanced glycation end products (RAGE), a member of the Ig superfamily, is a cellular binding site for Abeta. Here, we investigate the role of RAGE in apoptosis induced by distinct well characterized Abeta conformations: Abeta oligomers (AbetaOs), Abeta fibrils (AbetaFs), and Abeta aggregates (AbetaAs). In our in vitro system, treatment with polyclonal anti-RAGE antibodies significantly improves SHSY-5Y cell and neuronal survival exposed to either AbetaOs or AbetaAs but does not affect AbetaF toxicity. Interestingly, using site-specific antibodies, we demonstrate that targeting of the V(d) domain of RAGE attenuates AbetaO-induced toxicity in both SHSY-5Y cells and rat cortical neurons, whereas inhibition of AbetaA-induced apoptosis requires the neutralization of the C(1d) domain of the receptor. Thus, our data indicate that distinct regions of RAGE are involved in Abeta-induced cellular and neuronal toxicity with respect to the Abeta aggregation state, and they suggest the blockage of particular sites of the receptor as a potential therapeutic strategy to attenuate neuronal death.
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81
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Onozuka H, Nakajima A, Matsuzaki K, Shin RW, Ogino K, Saigusa D, Tetsu N, Yokosuka A, Sashida Y, Mimaki Y, Yamakuni T, Ohizumi Y. Nobiletin, a Citrus Flavonoid, Improves Memory Impairment and Aβ Pathology in a Transgenic Mouse Model of Alzheimer's Disease. J Pharmacol Exp Ther 2008; 326:739-44. [DOI: 10.1124/jpet.108.140293] [Citation(s) in RCA: 164] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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