251
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Wang CY, Wang T, Zheng W, Zhao BL, Danscher G, Chen YH, Wang ZY. Zinc overload enhances APP cleavage and Aβ deposition in the Alzheimer mouse brain. PLoS One 2010; 5:e15349. [PMID: 21179415 PMCID: PMC3003690 DOI: 10.1371/journal.pone.0015349] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 11/11/2010] [Indexed: 11/25/2022] Open
Abstract
Background Abnormal zinc homeostasis is involved in β-amyloid (Aβ) plaque formation and, therefore, the zinc load is a contributing factor in Alzheimer's disease (AD). However, the involvement of zinc in amyloid precursor protein (APP) processing and Aβ deposition has not been well established in AD animal models in vivo. Methodology/Principal Findings In the present study, APP and presenilin 1 (PS1) double transgenic mice were treated with a high dose of zinc (20 mg/ml ZnSO4 in drinking water). This zinc treatment increased APP expression, enhanced amyloidogenic APP cleavage and Aβ deposition, and impaired spatial learning and memory in the transgenic mice. We further examined the effects of zinc overload on APP processing in SHSY-5Y cells overexpressing human APPsw. The zinc enhancement of APP expression and cleavage was further confirmed in vitro. Conclusions/Significance The present data indicate that excess zinc exposure could be a risk factor for AD pathological processes, and alteration of zinc homeostasis is a potential strategy for the prevention and treatment of AD.
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Affiliation(s)
- Chun-Yan Wang
- Key Laboratory of Cell Biology of Ministry of Public Health, and Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang, China
| | - Tao Wang
- Key Laboratory of Cell Biology of Ministry of Public Health, and Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang, China
| | - Wei Zheng
- Key Laboratory of Cell Biology of Ministry of Public Health, and Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang, China
| | - Bao-Lu Zhao
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Academia Sinica, Beijing, China
| | - Gorm Danscher
- Department of Anatomy and Neurobiology, University of Aarhus, Aarhus, Denmark
| | - Yu-Hua Chen
- Key Laboratory of Cell Biology of Ministry of Public Health, and Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang, China
- * E-mail: (Z-YW); (Y-HC)
| | - Zhan-You Wang
- Key Laboratory of Cell Biology of Ministry of Public Health, and Key Laboratory of Medical Cell Biology of Ministry of Education, China Medical University, Shenyang, China
- * E-mail: (Z-YW); (Y-HC)
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252
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Chua SM, Ng BY, Lee TS. Genetic and Genomic Aspects of Alzheimer's Disease. PROCEEDINGS OF SINGAPORE HEALTHCARE 2010. [DOI: 10.1177/201010581001900408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Alzheimer's disease (AD) is the most common chronic neurodegenerative disease today, afflicting 35 million people worldwide. Age is the major risk factor. The heritability of AD is estimated to be around 60%. Less than 5% of AD cases are familial with early-onset of disease caused by specific gene mutations. Genetic studies over the past 2 decades have provided invaluable insights into this complex disease. Here we review AD from the latest genome-wide association studies (GWAS), and a brief review of the transcriptomics, proteomics, metabolomics and epigenetics. Ultimately, a system-wide approach is essential to integrating the diverse and complicated findings into a meaningful understanding of AD.
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Affiliation(s)
- Sze-Ming Chua
- Department of Psychiatry, Singapore General Hospital, Singapore
| | - Beng-Yeong Ng
- Department of Psychiatry, Singapore General Hospital, Singapore
| | - Tih-Shih Lee
- Department of Psychiatry, Singapore General Hospital, Singapore
- Duke University Medical School, Durham, North Carolina, USA
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253
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Ludtmann MHR, Boeckeler K, Williams RSB. Molecular pharmacology in a simple model system: implicating MAP kinase and phosphoinositide signalling in bipolar disorder. Semin Cell Dev Biol 2010; 22:105-13. [PMID: 21093602 PMCID: PMC3032892 DOI: 10.1016/j.semcdb.2010.11.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 11/10/2010] [Accepted: 11/11/2010] [Indexed: 01/20/2023]
Abstract
Understanding the mechanisms of drug action has been the primary focus for pharmacological researchers, traditionally using rodent models. However, non-sentient model systems are now increasingly being used as an alternative approach to better understand drug action or targets. One of these model systems, the social amoeba Dictyostelium, enables the rapid ablation or over-expression of genes, and the subsequent use of isogenic cell culture for the analysis of cell signalling pathways in pharmacological research. The model also supports an increasingly important ethical view of research, involving the reduction, replacement and refinement of animals in biomedical research. This review outlines the use of Dictyostelium in understanding the pharmacological action of two commonly used bipolar disorder treatments (valproic acid and lithium). Both of these compounds regulate mitogen activated protein (MAP) kinase and inositol phospholipid-based signalling by unknown means. Analysis of the molecular pathways targeted by these drugs in Dictyostelium and translation of discoveries to animal systems has helped to further understand the molecular mechanisms of these bipolar disorder treatments.
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Affiliation(s)
- Marthe H R Ludtmann
- Centre for Biomedical Sciences, School of Biological Sciences, Royal Holloway University of London, Egham, UK
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254
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Insulin deficiency exacerbates cerebral amyloidosis and behavioral deficits in an Alzheimer transgenic mouse model. Mol Neurodegener 2010; 5:46. [PMID: 21044348 PMCID: PMC2987993 DOI: 10.1186/1750-1326-5-46] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Accepted: 11/02/2010] [Indexed: 12/16/2022] Open
Abstract
Background Although increasing evidence has indicated that brain insulin dysfunction is a risk factor for Alzheimer disease (AD), the underlying mechanisms by which insulin deficiency may impact the development of AD are still obscure. Using a streptozotocin (STZ)-induced insulin deficient diabetic AD transgenic mouse model, we evaluated the effect of insulin deficiency on AD-like behavior and neuropathology. Results Our data showed that administration of STZ increased the level of blood glucose and reduced the level of serum insulin, and further decreased the phosphorylation levels of insulin receptors, and increased the activities of glycogen synthase kinase-3α/β and c-Jun N-terminal kinase in the APP/PS1 mouse brain. We further showed that STZ treatment promoted the processing of amyloid-β (Aβ) precursor protein resulting in increased Aβ generation, neuritic plaque formation, and spatial memory deficits in transgenic mice. Conclusions Our present data indicate that there is a close link between insulin deficient diabetes and cerebral amyloidosis in the pathogenesis of AD.
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255
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Gao HL, Xu H, Xin N, Zheng W, Chi ZH, Wang ZY. Disruption of the CaMKII/CREB signaling is associated with zinc deficiency-induced learning and memory impairments. Neurotox Res 2010; 19:584-91. [PMID: 20593259 DOI: 10.1007/s12640-010-9206-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 06/12/2010] [Accepted: 06/21/2010] [Indexed: 12/28/2022]
Abstract
Many studies have shown that zinc deficiency not only retards growth, but also affects several brain functions, including learning and memory. However, the underlying mechanism of impaired hippocampus-dependent learning and memory under zinc deficiency is poorly understood. In this study, young mice were fed a zinc-deficient diet (0.85 ppm) for 5 weeks. Morris water maze result showed that zinc deficiency results in spatial learning impairment. We then examined whether zinc depletion-induced learning and memory defects are associated with changes in signaling molecules essential for the expression of long-term potentiation. Immunoblot results showed that the protein levels of calmodulin (CaM), phosphorylated CaM-dependent protein kinase II (CaMKII), and phosphorylated cAMP-responsive element binding protein (CREB) were significantly reduced, whereas the total protein levels of CaMKII and CREB did not change in the zinc-deficient hippocampus. Thus, we provide a previously unrecognized mechanism whereby zinc deficiency impairs hippocampal learning and memory, at least in part, through disruption of the CaM/CaMKII/CREB signaling pathway.
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Affiliation(s)
- Hui-Ling Gao
- Key Lab of Cell Biology of Ministry of Education of China, China Medical University, Bei-Er Road 92, Shenyang 110001, People's Republic of China
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256
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Petit-Paitel A. GSK-3β : une kinase au cœur des maladies neuro-dégénératives ? Med Sci (Paris) 2010; 26:516-21. [DOI: 10.1051/medsci/2010265516] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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257
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Nuutinen T, Suuronen T, Kauppinen A, Salminen A. Valproic acid stimulates clusterin expression in human astrocytes: Implications for Alzheimer's disease. Neurosci Lett 2010; 475:64-8. [DOI: 10.1016/j.neulet.2010.03.041] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/04/2010] [Accepted: 03/15/2010] [Indexed: 10/19/2022]
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258
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Loss of tau elicits axonal degeneration in a mouse model of Alzheimer's disease. Neuroscience 2010; 169:516-31. [PMID: 20434528 DOI: 10.1016/j.neuroscience.2010.04.037] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 04/01/2010] [Accepted: 04/16/2010] [Indexed: 01/20/2023]
Abstract
A central issue in the pathogenesis of tauopathy is the question of how tau protein dysfunction leads to neurodegeneration. We have previously demonstrated that the absence of tau protein is associated with destabilization of microtubules and impaired neurite outgrowth (Dawson et al., 2001; Rapoport et al., 2002). We now hypothesize that the absence of functional tau protein may render the central nervous system more vulnerable to secondary insults such as the overexpression of mutated beta amyloid precursor protein (APP) and traumatic brain injury. We therefore crossed tau knockout mice (Dawson et al., 2001) to mice overexpressing a mutated human APP (APP(670,671), A(sw)) (Hsiao et al., 1996) and created a mouse model (A(sw)/mTau(-/-)) that provides evidence that the loss of tau function causes degeneration of neuronal processes. The overexpression of APP(670,671) in tau knockout mice, elicits the extensive formation of axonal spheroids. While spheroids are only found associated with Abeta plaques in mice expressing APP(670,671) on an endogenous mouse tau background (Irizarry et al., 1997), A(sw)/mTau(-/-) mice have spheroids not only surrounding Abeta plaques but also in white matter tracks and in the neuropil. Plaque associated and neuropil dystrophic neurites and spheroids are prominent features of Alzheimer's disease (Masliah et al., 1993; Terry, 1996; Stokin et al., 2005), and our current data suggests that loss of tau function may lead to neurodegeneration.
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259
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Smith AM, Gibbons HM, Dragunow M. Valproic acid enhances microglial phagocytosis of amyloid-beta(1-42). Neuroscience 2010; 169:505-15. [PMID: 20423723 DOI: 10.1016/j.neuroscience.2010.04.041] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 04/01/2010] [Accepted: 04/19/2010] [Indexed: 01/17/2023]
Abstract
Alzheimer's disease (AD) is a prevalent neurodegenerative disorder manifested by memory loss, confusion and changes in mood. A principal pathology of this debilitating disorder is extracellular deposits of amyloid-beta (Abeta) protein. The "amyloid hypothesis" postulates that a build-up of Abeta protein is responsible for neuronal loss and the ensuing symptoms of AD. One possible mechanism of Abeta clearance, and hence AD therapy, is phagocytosis of Abeta protein by microglial cells. Microglia are the brain's resident immune cells and phagocytosis is one of their innate functions. We are interested in identifying molecules that augment microglial-mediated phagocytosis of Abeta protein. We used the rodent BV-2 microglial cell line which readily phagocytose fluorescent latex beads and synthetic Abeta(1-42) peptide. BV-2 cells treated with the neuroactive drug valproic acid (VPA) showed greatly enhanced phagocytic activity for both latex beads and Abeta. VPA also reduced microglial viability by inducing apoptosis, as previously reported. The relevance of these in vitro results to the treatment of AD is unclear but further investigation into the effects of VPA on the clearance of Abeta through enhanced microglial phagocytosis is warranted.
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Affiliation(s)
- A M Smith
- Department of Pharmacology, Faculty of Medical and Health Sciences and the National Research Centre for Growth and Development, The University of Auckland, Auckland, New Zealand
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260
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Venkataramani V, Rossner C, Iffland L, Schweyer S, Tamboli IY, Walter J, Wirths O, Bayer TA. Histone deacetylase inhibitor valproic acid inhibits cancer cell proliferation via down-regulation of the alzheimer amyloid precursor protein. J Biol Chem 2010; 285:10678-89. [PMID: 20145244 PMCID: PMC2856276 DOI: 10.1074/jbc.m109.057836] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 02/05/2010] [Indexed: 11/06/2022] Open
Abstract
The beta-amyloid precursor protein (APP) represents a type I transmembrane glycoprotein that is ubiquitously expressed. In the brain, it is a key player in the molecular pathogenesis of Alzheimer disease. Its physiological function is however less well understood. Previous studies showed that APP is up-regulated in prostate, colon, pancreatic tumor, and oral squamous cell carcinoma. In this study, we show that APP has an essential role in growth control of pancreatic and colon cancer. Abundant APP staining was found in human pancreatic adenocarcinoma and colon cancer tissue. Interestingly, treating pancreatic and colon cancer cells with valproic acid (VPA, 2-propylpentanoic acid), a known histone deacetylase (HDAC) inhibitor, leads to up-regulation of GRP78, an endoplasmic reticulum chaperone immunoglobulin-binding protein. GRP78 is involved in APP maturation and inhibition of tumor cell growth by down-regulation of APP and secreted soluble APPalpha. Trichostatin A, a pan-HDAC inhibitor, also lowered APP and increased GRP78 levels. In contrast, treating cells with valpromide, a VPA derivative lacking HDAC inhibitory properties, had no effect on APP levels. VPA did not modify the level of epidermal growth factor receptor, another type I transmembrane protein, and APLP2, a member of the APP family, demonstrating the specificity of the VPA effect on APP. Small interfering RNA-mediated knockdown of APP also resulted in significantly decreased cell growth. Based on these observations, the data suggest that APP down-regulation via HDAC inhibition provides a novel mechanism for pancreatic and colon cancer therapy.
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Affiliation(s)
- Vivek Venkataramani
- From the Department of Molecular Psychiatry, Alzheimer Ph.D. Graduate School, and
| | - Christian Rossner
- From the Department of Molecular Psychiatry, Alzheimer Ph.D. Graduate School, and
| | - Lara Iffland
- From the Department of Molecular Psychiatry, Alzheimer Ph.D. Graduate School, and
| | - Stefan Schweyer
- Department of Pathology, University of Goettingen, 37075 Goettingen and
| | - Irfan Y. Tamboli
- the Department of Molecular Cell Biology, University of Bonn, 53127 Bonn, Germany
| | - Jochen Walter
- the Department of Molecular Cell Biology, University of Bonn, 53127 Bonn, Germany
| | - Oliver Wirths
- From the Department of Molecular Psychiatry, Alzheimer Ph.D. Graduate School, and
| | - Thomas A. Bayer
- From the Department of Molecular Psychiatry, Alzheimer Ph.D. Graduate School, and
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261
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Valproic acid as a promising agent to combat Alzheimer's disease. Brain Res Bull 2010; 81:3-6. [DOI: 10.1016/j.brainresbull.2009.09.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 09/04/2009] [Accepted: 09/07/2009] [Indexed: 01/03/2023]
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262
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Abstract
The anticonvulsant properties of VPA (valproic acid), a branched short-chain fatty acid, were serendipitously discovered in 1963. Since then, therapeutic roles of VPA have increased to include bipolar disorder and migraine prophylaxis, and have more recently been proposed in cancer, Alzheimer's disease and HIV treatment. These numerous therapeutic roles elevate VPA to near 'panacea' level. Surprisingly, the mechanisms of action of VPA in the treatment of many of these disorders remain unclear, although it has been shown to alter a wide variety of signalling pathways and a small number of direct targets. To analyse the mechanism of action of VPA, a number of studies have defined the structural characteristics of VPA-related compounds giving rise to distinct therapeutic and cellular effects, including adverse effects such as teratogenicity and hepatotoxicity. These studies raise the possibility of identifying target-specific novel compounds, providing better therapeutic action or reduced side effects. This short review will describe potential therapeutic pathways targeted by VPA, and highlight studies showing structural constraints necessary for these effects.
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263
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Hunsberger J, Austin DR, Henter ID, Chen G. The neurotrophic and neuroprotective effects of psychotropic agents. DIALOGUES IN CLINICAL NEUROSCIENCE 2009. [PMID: 19877500 PMCID: PMC2804881 DOI: 10.31887/dcns.2009.11.3/jhunsberger] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Accumulating evidence suggests that psychotropic agents such as mood stabilizers, antidepressants, and antipsychotics realize their neurotrophic/neuroprotective effects by activating the mitogen activated protein kinaselextracellular signal-related kinase, PI3-kinase, and winglesslglycogen synthase kinase (GSK) 3 signaling pathways. These agents also upregulate the expression of trophic/protective molecules such as brain-derived neurotrophic factor, nerve growth factor, B-cell lymphoma 2, serine-threonine kinase, and Bcl-2 associated athanogene 1, and inactivate proapoptotic molecules such as GSK-3, They also promote neurogenesis and are protective in models of neurodegenerative diseases and ischemia. Most if not all, of this evidence was collected from animal studies that used clinically relevant treatment regimens. Furthermore, human imaging studies have found that these agents increase the volume and density of brain tissue, as well as levels of N-acetyl aspartate and glutamate in selected brain regions. Taken together, these data suggest that the neurotrophic/neuroprotective effects of these agents have broad therapeutic potential in the treatment, not only of mood disorders and schizophrenia, but also neurodegenerative diseases and ischemia.
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Affiliation(s)
- Joshua Hunsberger
- Laboratory of Molecular Pathophysiology and Experimental Therapeutics, Mood and Anxiety Disorders Program, NIMH, NIH, Bethesda, MD, 20892, USA
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264
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Chuang DM, Leng Y, Marinova Z, Kim HJ, Chiu CT. Multiple roles of HDAC inhibition in neurodegenerative conditions. Trends Neurosci 2009; 32:591-601. [PMID: 19775759 PMCID: PMC2771446 DOI: 10.1016/j.tins.2009.06.002] [Citation(s) in RCA: 475] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 06/26/2009] [Accepted: 06/26/2009] [Indexed: 12/24/2022]
Abstract
Histone deacetylases (HDACs) play a key role in homeostasis of protein acetylation in histones and other proteins and in regulating fundamental cellular activities such as transcription. A wide range of brain disorders are associated with imbalances in protein acetylation levels and transcriptional dysfunctions. Treatment with various HDAC inhibitors can correct these deficiencies and has emerged as a promising new strategy for therapeutic intervention in neurodegenerative disease. Here, we review and discuss intriguing recent developments in the use of HDAC inhibitors to combat neurodegenerative conditions in cellular and disease models. HDAC inhibitors have neuroprotective, neurotrophic and anti-inflammatory properties; improvements in neurological performance, learning/memory and other disease phenotypes are frequently seen in these models. We discuss the targets and mechanisms underlying these effects of HDAC inhibition and comment on the potential for some HDAC inhibitors to prove clinically effective in the treatment of neurodegenerative disorders.
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Affiliation(s)
- De-Maw Chuang
- Molecular Neurobiology Section, National Institute of Mental Health, National Institutes of Health, 10 Center Drive MSC 1363, Bethesda, MD 20892-1363, USA.
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265
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Nalivaeva NN, Belyaev ND, Turner AJ. Sodium valproate: an old drug with new roles. Trends Pharmacol Sci 2009; 30:509-14. [PMID: 19762089 DOI: 10.1016/j.tips.2009.07.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 07/19/2009] [Accepted: 07/21/2009] [Indexed: 01/16/2023]
Abstract
Sodium valproate, or Epilim, has been widely used as a broad spectrum, anticonvulsant drug for over 40 years and exhibits a good safety profile. Some of the actions of valproate arise from its more recently described histone deacetylase (HDAC) inhibitory properties and hence it can specifically modulate gene expression. There is now accumulating evidence that HDAC inhibitors may have potential in the treatment of CNS disorders and, in this context, valproate has much potential as a brain-penetrant, clinically available and well tested drug. This article reviews the pharmacology of this remarkable molecule, focusing on its actions as a neuroprotectant and hence with new potential in the treatment of neurodegenerative diseases.
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Affiliation(s)
- Natalia N Nalivaeva
- Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
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266
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Larner AJ. Epileptic seizures in AD patients. Neuromolecular Med 2009; 12:71-7. [PMID: 19557550 DOI: 10.1007/s12017-009-8076-z] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 06/18/2009] [Indexed: 10/20/2022]
Abstract
Epileptic seizures have long been recognised as a complication of the clinical syndrome of Alzheimer's disease, particularly in advanced disease, but have hitherto been viewed essentially as epiphenomena of the neurodegenerative process. Progress with animal models of Alzheimer's disease has suggested that this view may be incorrect, and that seizures may be a reflection of pathophysiological processes similar to or overlapping with those responsible for cognitive decline. This overlap between neuropsychological and neurophysiological changes suggests that seizures in Alzheimer's disease may be a valid therapeutic target, over and above symptomatic treatment. This article reviews data on the prevalence of seizures in Alzheimer's disease, seizure types, pathophysiology and treatment. Seizure prevalence increases with disease duration, but early-onset disease is associated with a greater risk of seizures, in part related to the frequency of presenilin-1 gene mutations in early-onset disease. Seizures are mostly of partial origin, with both complex partial and secondary generalised seizures. Seizure pathophysiology may relate to increased amyloid beta-peptide production, structural alterations in neurones related to cytoskeletal dysfunction, cerebrovascular changes, neurotransmitter dysfunction or combinations thereof. Through modification of these pathophysiological pathways, there may be possible roles for anti-epileptic drugs such as sodium valproate and lacosamide in the treatment of Alzheimer's disease. In summary, epileptic seizures are part of the AD phenotype, and merit further investigation.
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Affiliation(s)
- A J Larner
- Cognitive Function Clinic, Walton Centre for Neurology and Neurosurgery, Lower Lane, Fazakerley, Liverpool, UK.
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267
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Qing H, He G, Ly PT, Fox CJ, Staufenbiel M, Cai F, Zhang Z, Wei S, Sun X, Chen CH, Zhou W, Wang K, Song W. Valproic acid inhibits Ab production, neuritic plaque formation, and behavioral deficits in Alzheimer's disease mouse models. J Biophys Biochem Cytol 2008. [DOI: 10.1083/jcb1833oia8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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