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Grimm MOW, Mett J, Grimm HS, Hartmann T. APP Function and Lipids: A Bidirectional Link. Front Mol Neurosci 2017; 10:63. [PMID: 28344547 PMCID: PMC5344993 DOI: 10.3389/fnmol.2017.00063] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 02/24/2017] [Indexed: 12/14/2022] Open
Abstract
Extracellular neuritic plaques, composed of aggregated amyloid-β (Aβ) peptides, are one of the major histopathological hallmarks of Alzheimer's disease (AD), a progressive, irreversible neurodegenerative disorder and the most common cause of dementia in the elderly. One of the most prominent risk factor for sporadic AD, carrying one or two aberrant copies of the apolipoprotein E (ApoE) ε4 alleles, closely links AD to lipids. Further, several lipid classes and fatty acids have been reported to be changed in the brain of AD-affected individuals. Interestingly, the observed lipid changes in the brain seem not only to be a consequence of the disease but also modulate Aβ generation. In line with these observations, protective lipids being able to decrease Aβ generation and also potential negative lipids in respect to AD were identified. Mechanistically, Aβ peptides are generated by sequential proteolytic processing of the amyloid precursor protein (APP) by β- and γ-secretase. The α-secretase appears to compete with β-secretase for the initial cleavage of APP, preventing Aβ production. All APP-cleaving secretases as well as APP are transmembrane proteins, further illustrating the impact of lipids on Aβ generation. Beside the pathological impact of Aβ, accumulating evidence suggests that Aβ and the APP intracellular domain (AICD) play an important role in regulating lipid homeostasis, either by direct effects or by affecting gene expression or protein stability of enzymes involved in the de novo synthesis of different lipid classes. This review summarizes the current literature addressing the complex bidirectional link between lipids and AD and APP processing including lipid alterations found in AD post mortem brains, lipids that alter APP processing and the physiological functions of Aβ and AICD in the regulation of several lipid metabolism pathways.
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Affiliation(s)
- Marcus O. W. Grimm
- Experimental Neurology, Saarland UniversityHomburg/Saar, Germany
- Neurodegeneration and Neurobiology, Saarland UniversityHomburg/Saar, Germany
- Deutsches Institut für DemenzPrävention (DIDP), Saarland UniversityHomburg/Saar, Germany
| | - Janine Mett
- Experimental Neurology, Saarland UniversityHomburg/Saar, Germany
| | - Heike S. Grimm
- Experimental Neurology, Saarland UniversityHomburg/Saar, Germany
| | - Tobias Hartmann
- Experimental Neurology, Saarland UniversityHomburg/Saar, Germany
- Neurodegeneration and Neurobiology, Saarland UniversityHomburg/Saar, Germany
- Deutsches Institut für DemenzPrävention (DIDP), Saarland UniversityHomburg/Saar, Germany
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52
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Kim M, Nevado-Holgado A, Whiley L, Snowden SG, Soininen H, Kloszewska I, Mecocci P, Tsolaki M, Vellas B, Thambisetty M, Dobson RJ, Powell JF, Lupton MK, Simmons A, Velayudhan L, Lovestone S, Proitsi P, Legido-Quigley C. Association between Plasma Ceramides and Phosphatidylcholines and Hippocampal Brain Volume in Late Onset Alzheimer's Disease. J Alzheimers Dis 2017; 60:809-817. [PMID: 27911300 PMCID: PMC5676755 DOI: 10.3233/jad-160645] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2016] [Indexed: 12/14/2022]
Abstract
Lipids such as ceramides and phosphatidylcholines (PC) have been found altered in the plasma of Alzheimer's disease (AD) patients in a number of discovery studies. For this reason, the levels of 6 ceramides and 3 PCs, with different fatty acid length and saturation levels, were measured in the plasma from 412 participants (AD n = 205, Control n = 207) using mass spectrometry coupled with ultra-performance liquid chromatography. After this, associations with AD status, brain atrophy, and age-related effects were studied. In the plasma of AD participants, cross-sectional analysis revealed elevated levels of three ceramides (Cer16:0 p < 0.01, Cer18:0 p < 0.01, Cer24:1 p < 0.05). In addition, two PCs in AD plasma (PC36:5 p < 0.05, PC38:6 p < 0.05) were found to be depleted compared to the control group, with PC36:5 also associating with hippocampal atrophy (p < 0.01). Age-specific analysis further revealed that levels of Cer16:0, Cer18:0, and Cer20:0 were associated with hippocampal atrophy only in younger participants (age < 75, p < 0.05), while all 3 PCs did so in the older participants (age > 75, p < 0.05). PC36:5 was associated with AD status in the younger group (p < 0.01), while PC38:6 and 40:6 did so in the older group (p < 0.05). In this study, elevated ceramides and depleted PCs were found in the plasma from 205 AD volunteers. Our findings also suggest that dysregulation in PC and ceramide metabolism could be occurring in different stages of AD progression.
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Affiliation(s)
- Min Kim
- Institute of Pharmaceutical Science, King’s College London, London, UK
| | | | - Luke Whiley
- Institute of Pharmaceutical Science, King’s College London, London, UK
| | - Stuart G. Snowden
- Institute of Pharmaceutical Science, King’s College London, London, UK
| | - Hilkka Soininen
- Department of Neurology, Kuopio University Hospital and University of Eastern Finland, Kuopio, Finland
| | - Iwona Kloszewska
- Department of Old Age Psychiatry & Psychotic Disorders, Medical University of Lodz, Lodz, Poland
| | - Patrizia Mecocci
- Section of Gerontology and Geriatrics, Department of Medicine, University of Perugia, Perugia, Italy
| | - Magda Tsolaki
- Third Department of Neurology, Memory and Dementia Centre, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Bruno Vellas
- Department of Internal and Geriatrics Medicine, INSERM U 1027, Gerontopole, Hôpitaux de Toulouse, Toulouse, France
| | - Madhav Thambisetty
- Clinical and Translational Neuroscience Unit, Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA
| | - Richard J.B. Dobson
- Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK
| | - John F. Powell
- Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK
| | - Michelle K. Lupton
- Genetic Epidemiology, QIMR Berghofer Medical Research Institute, Brisbane, Qld, Australia
| | - Andy Simmons
- Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK
- National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) for Mental Health at South London and Maudsley NHS Foundation Trust, UK
| | - Latha Velayudhan
- Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK
| | | | - Petroula Proitsi
- Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK
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53
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Thomas MH, Pelleieux S, Vitale N, Olivier JL. Dietary arachidonic acid as a risk factor for age-associated neurodegenerative diseases: Potential mechanisms. Biochimie 2016; 130:168-177. [PMID: 27473185 DOI: 10.1016/j.biochi.2016.07.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 07/24/2016] [Indexed: 11/28/2022]
Abstract
Alzheimer's disease and associated diseases constitute a major public health concern worldwide. Nutrition-based, preventive strategies could possibly be effective in delaying the occurrence of these diseases and lower their prevalence. Arachidonic acid is the second major polyunsaturated fatty acid (PUFA) and several studies support its involvement in Alzheimer's disease. The objective of this review is to examine how dietary arachidonic acid contributes to Alzheimer's disease mechanisms and therefore to its prevention. First, we explore the sources of neuronal arachidonic acid that could potentially originate from either the conversion of linoleic acid, or from dietary sources and transfer across the blood-brain-barrier. In a second part, a brief overview of the role of the two main agents of Alzheimer's disease, tau protein and Aβ peptide is given, followed by the examination of the relationship between arachidonic acid and the disease. Third, the putative mechanisms by which arachidonic acid could influence Alzheimer's disease occurrence and evolution are presented. The conclusion is devoted to what remains to be determined before integrating arachidonic acid in the design of preventive strategies against Alzheimer's disease and other neurodegenerative diseases.
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Affiliation(s)
- Mélanie H Thomas
- Unité de Recherche Aliment et Fonctionnalité des Produits Animaux (URAFPA), INRA USC 0340, Université de Lorraine, Nancy, France
| | - Sandra Pelleieux
- Unité de Recherche Aliment et Fonctionnalité des Produits Animaux (URAFPA), INRA USC 0340, Université de Lorraine, Nancy, France
| | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives (INCI), UPR CNRS 3212, Université de Strasbourg, Strasbourg, France
| | - Jean Luc Olivier
- Unité de Recherche Aliment et Fonctionnalité des Produits Animaux (URAFPA), INRA USC 0340, Université de Lorraine, Nancy, France.
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54
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Ellis B, Hye A, Snowden SG. Metabolic Modifications in Human Biofluids Suggest the Involvement of Sphingolipid, Antioxidant, and Glutamate Metabolism in Alzheimer's Disease Pathogenesis. J Alzheimers Dis 2016; 46:313-27. [PMID: 25835424 DOI: 10.3233/jad-141899] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative dementia, with the accumulation of extracellular amyloid-β and formation of neurofibrillary tau tangles as leading explanations of pathology. With the difficulties of studying the brain directly, it is hoped that identifying the effect of AD on the metabolite composition of biofluids will provide insights into underlying mechanisms of pathology. The present review identified 705 distinct metabolite reports representing 448 structurally distinct metabolites in six human biofluids, with 147 metabolites increased and 214 metabolites decreased with AD, while 80 metabolites showed inconsistent shifts. Sphingolipid, antioxidant, and glutamate metabolism were found to be strongly associated with AD and were selected for detailed investigation of their role in pathogenesis. In plasma, two ceramides increased and eight sphingomyelins decreased with AD, with total ceramides shown to increase in both serum and cerebrospinal fluid. In general antioxidants were shown to be depleted, with oxidative stress markers elevated in a range of biofluids in patients suggesting AD produces a pro-oxidative environment. Shifts in glutamate and glutamine and elevation of 4-hydroxy-2-nonenal suggests peroxidation of the astrocyte lipid bilayer resulting in reduced glutamate clearance from the synaptic cleft, suggesting a excitotoxicity component to AD pathology; however, due to inconsistencies in literature reports, reliable interpretation is difficult. The present review has shown that metabolite shifts in biofluids can provide valuable insights into potential pathological mechanisms in the brain, with sphingolipid, antioxidant, and glutamate metabolism being implicated in AD pathology.
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Affiliation(s)
- Ben Ellis
- Kings College London, School of Medicine, London, UK
| | - Abdul Hye
- Institute of Psychiatry, Department of Old Age Psychiatry, Kings College London, London, UK
| | - Stuart G Snowden
- Institute of Psychiatry, Department of Old Age Psychiatry, Kings College London, London, UK
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55
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Li X, Feng Y, Wu W, Zhao J, Fu C, Li Y, Ding Y, Wu B, Gong Y, Yang G, Zhou X. Sex differences between APPswePS1dE9 mice in A-beta accumulation and pancreatic islet function during the development of Alzheimer’s disease. Lab Anim 2016; 50:275-85. [PMID: 26519428 DOI: 10.1177/0023677215615269] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The pathogenesis of Alzheimer’s disease (AD), a type of neurodegenerative disease characterized by learning and memory impairment, is often associated with pathological features, such as amyloid-beta (Aβ) accumulation and insulin resistance. The transgenic mouse, APPswePS1dE9 (APP/PS1), is one of the most commonly used animal models in pathogenesis studies of AD. The purpose of this study is to investigate the sex differences between APP/PS1 mice in the pathogenesis of AD. The impairment of glucose and insulin tolerance was found to develop earlier in male APP/PS1 mice than in females. Plasma insulin levels were significantly decreased in male APP/PS1 mice, while total cholesterol levels in male APP/PS1 mice were higher than those in females. Triglyceride levels in male mice in both the wild-type (WT) and APP/PS1 groups were higher than in their female littermates. Soluble and insoluble Aβ levels in female APP/PS1 mouse brains were higher than those in males. And the learning and memorizing abilities of female APP/PS1 mice were poorer than those of males. Our results concluded that there were sex differences in Aβ formation, pancreatic islet function and insulin sensitivity between male and female APP/PS1 mice during the pathogenesis of AD.
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Affiliation(s)
- Xin Li
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Ying Feng
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Wei Wu
- West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China
| | - Jia Zhao
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Chunmei Fu
- West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China
| | - Yang Li
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Yangnan Ding
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Binghuo Wu
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Yanju Gong
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Guizhi Yang
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Xue Zhou
- West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
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56
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Dinkins MB, Dasgupta S, Wang G, Zhu G, He Q, Kong JN, Bieberich E. The 5XFAD Mouse Model of Alzheimer's Disease Exhibits an Age-Dependent Increase in Anti-Ceramide IgG and Exogenous Administration of Ceramide Further Increases Anti-Ceramide Titers and Amyloid Plaque Burden. J Alzheimers Dis 2016; 46:55-61. [PMID: 25720409 DOI: 10.3233/jad-150088] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We present evidence that 5XFAD Alzheimer's disease model mice develop an age-dependent increase in antibodies against ceramide, suggesting involvement of autoimmunity against ceramide in Alzheimer's disease pathology. To test this, we increased serum anti-ceramide IgG (2-fold) by ceramide administration and analyzed amyloid plaque formation in 5XFAD mice. There were no differences in soluble or total amyloid-β levels. However, females receiving ceramide had increased plaque burden (number, area, and size) compared to controls. Ceramide-treated mice showed an increase of serum exosomes (up to 3-fold using Alix as marker), suggesting that systemic anti-ceramide IgG and exosome levels are correlated with enhanced plaque formation.
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57
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Yang S, Liu W, Lu S, Tian YZ, Wang WY, Ling TJ, Liu RT. A Novel Multifunctional Compound Camellikaempferoside B Decreases Aβ Production, Interferes with Aβ Aggregation, and Prohibits Aβ-Mediated Neurotoxicity and Neuroinflammation. ACS Chem Neurosci 2016; 7:505-18. [PMID: 27015590 DOI: 10.1021/acschemneuro.6b00091] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Accumulating evidence suggested that soluble oligomeric β-amyloid protein (Aβ) exerts diverse roles in neuronal cell death, neuroinflammation, oxidative stress, and the eventual dementia associated with Alzheimer's disease (AD). Developing an agent with multiple properties may be a reasonable strategy for the treatment of AD. In this study, we isolated a novel multifunctional compound named camellikaempferoside B (YCF-2) from Fuzhuan brick tea. YCF-2 consists of kaempferol backbone, p-coumaric acid (p-CA) group, and a novel structure of rhamnopyranosyl group at the C-4' position, possessing the properties of both kaempferol and p-CA. YCF-2 significantly inhibited Aβ production by decreasing β-secretase activity. Moreover, YCF-2 suppressed Aβ42 fibrillation and facilitated nontoxic oligomer formation by binding to Aβ42 oligomers and by blocking the conformational transition to β-sheet. Furthermore, YCF-2 ameliorated Aβ-induced neuronal cell death, ROS production, inflammatory factor release, and microglia activation by blocking the NF-κB signaling pathway in microglia. These findings indicated that YCF-2 with a novel lead structure has potential applications for drug development for AD treatment.
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Affiliation(s)
- Shigao Yang
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Wen Liu
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
- School
of Life Science, Anhui Agricultural University, Hefei 230036, China
| | - Shuai Lu
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Yong-zhen Tian
- State
Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University 130 West Changjiang Rd., Hefei 230036, P. R. China
| | - Wei-yun Wang
- School
of Life Science, Anhui Agricultural University, Hefei 230036, China
| | - Tie-jun Ling
- State
Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University 130 West Changjiang Rd., Hefei 230036, P. R. China
| | - Rui-tian Liu
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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58
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Forloni G, Artuso V, La Vitola P, Balducci C. Oligomeropathies and pathogenesis of Alzheimer and Parkinson's diseases. Mov Disord 2016; 31:771-81. [DOI: 10.1002/mds.26624] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 02/11/2016] [Accepted: 02/15/2016] [Indexed: 12/13/2022] Open
Affiliation(s)
- Gianluigi Forloni
- Departement of Neuroscience; IRCCS, Istituto di Ricerche Farmacologiche “Mario Negri,”; Milano Italy
| | | | - Pietro La Vitola
- Departement of Neuroscience; IRCCS, Istituto di Ricerche Farmacologiche “Mario Negri,”; Milano Italy
| | - Claudia Balducci
- Departement of Neuroscience; IRCCS, Istituto di Ricerche Farmacologiche “Mario Negri,”; Milano Italy
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59
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Ghasemi R, Dargahi L, Ahmadiani A. Integrated sphingosine-1 phosphate signaling in the central nervous system: From physiological equilibrium to pathological damage. Pharmacol Res 2016; 104:156-64. [DOI: 10.1016/j.phrs.2015.11.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 11/14/2015] [Accepted: 11/15/2015] [Indexed: 01/09/2023]
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60
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Hong JH, Kang JW, Kim DK, Baik SH, Kim KH, Shanta SR, Jung JH, Mook-Jung I, Kim KP. Global changes of phospholipids identified by MALDI imaging mass spectrometry in a mouse model of Alzheimer's disease. J Lipid Res 2015; 57:36-45. [PMID: 26538545 DOI: 10.1194/jlr.m057869] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Indexed: 12/13/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia; however, at the present time there is no disease-modifying drug for AD. There is increasing evidence supporting the role of lipid changes in the process of normal cognitive aging and in the etiology of age-related neurodegenerative diseases. AD is characterized by the presence of intraneuronal protein clusters and extracellular aggregates of β-amyloid (Aβ). Disrupted Aβ kinetics may activate intracellular signaling pathways, including tau hyperphosphorylation and proinflammatory pathways. We analyzed and visualized the lipid profiles of mouse brains using MALDI-TOF MS. Direct tissue analysis by MALDI-TOF imaging MS (IMS) can determine the relative abundance and spatial distribution of specific lipids in different tissues. We used 5XFAD mice that almost exclusively generate and rapidly accumulate massive cerebral levels of Aβ-42 (1). Our data showed changes in lipid distribution in the mouse frontal cortex, hippocampus, and subiculum, where Aβ plaques are first generated in AD. Our results suggest that MALDI-IMS is a powerful tool for analyzing the distribution of various phospholipids and that this application might provide novel insight into the prediction of disease.
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Affiliation(s)
- Ji Hye Hong
- Department of Applied Chemistry and Institute of Natural Sciences, College of Applied Sciences, Kyung Hee University, Yongin, Republic of Korea
| | - Jeong Won Kang
- Department of Applied Chemistry and Institute of Natural Sciences, College of Applied Sciences, Kyung Hee University, Yongin, Republic of Korea
| | - Dong Kyu Kim
- Department of Biochemistry and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Sung Hoon Baik
- Department of Biochemistry and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Kyung Ho Kim
- Department of Biochemistry and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Selina Rahman Shanta
- Department of Applied Chemistry and Institute of Natural Sciences, College of Applied Sciences, Kyung Hee University, Yongin, Republic of Korea
| | - Jae Hun Jung
- Department of Applied Chemistry and Institute of Natural Sciences, College of Applied Sciences, Kyung Hee University, Yongin, Republic of Korea
| | - Inhee Mook-Jung
- Department of Biochemistry and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Kwang Pyo Kim
- Department of Applied Chemistry and Institute of Natural Sciences, College of Applied Sciences, Kyung Hee University, Yongin, Republic of Korea
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61
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Klosinski LP, Yao J, Yin F, Fonteh AN, Harrington MG, Christensen TA, Trushina E, Brinton RD. White Matter Lipids as a Ketogenic Fuel Supply in Aging Female Brain: Implications for Alzheimer's Disease. EBioMedicine 2015; 2:1888-904. [PMID: 26844268 PMCID: PMC4703712 DOI: 10.1016/j.ebiom.2015.11.002] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 10/24/2015] [Accepted: 11/02/2015] [Indexed: 01/28/2023] Open
Abstract
White matter degeneration is a pathological hallmark of neurodegenerative diseases including Alzheimer's. Age remains the greatest risk factor for Alzheimer's and the prevalence of age-related late onset Alzheimer's is greatest in females. We investigated mechanisms underlying white matter degeneration in an animal model consistent with the sex at greatest Alzheimer's risk. Results of these analyses demonstrated decline in mitochondrial respiration, increased mitochondrial hydrogen peroxide production and cytosolic-phospholipase-A2 sphingomyelinase pathway activation during female brain aging. Electron microscopic and lipidomic analyses confirmed myelin degeneration. An increase in fatty acids and mitochondrial fatty acid metabolism machinery was coincident with a rise in brain ketone bodies and decline in plasma ketone bodies. This mechanistic pathway and its chronologically phased activation, links mitochondrial dysfunction early in aging with later age development of white matter degeneration. The catabolism of myelin lipids to generate ketone bodies can be viewed as a systems level adaptive response to address brain fuel and energy demand. Elucidation of the initiating factors and the mechanistic pathway leading to white matter catabolism in the aging female brain provides potential therapeutic targets to prevent and treat demyelinating diseases such as Alzheimer's and multiple sclerosis. Targeting stages of disease and associated mechanisms will be critical. Mitochondrial dysfunction activates mechanisms for catabolism of myelin lipids to generate ketone bodies for ATP production. Mechanisms leading to ketone body driven energy production in brain coincide with stages of reproductive aging in females. Sequential activation of myelin catabolism pathway during aging provides multiple therapeutic targets and windows of efficacy.
The mechanisms underlying white matter degeneration, a hallmark of multiple neurodegenerative diseases including Alzheimer's, remain unclear. Herein we provide a mechanistic pathway, spanning multiple transitions of aging, that links mitochondrial dysfunction early in aging with later age white matter degeneration. Catabolism of myelin lipids to generate ketone bodies can be viewed as an adaptive survival response to address brain fuel and energy demand. Women are at greatest risk of late-onset-AD, thus, our analyses in female brain address mechanisms of AD pathology and therapeutic targets to prevent, delay and treat AD in the sex most affected with potential relevance to men.
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Key Words
- ABAD, Aβ-binding alcohol dehydrogenase
- ABAD, Aβ-binding-alcohol-dehydrogenase
- ACER3, alkaline ceramidase
- AD, Alzheimer's disease
- APO-ε4, apolipoprotein ε4
- APP, amyloid precursor protein
- Aging oxidative stress
- Alzheimer's disease
- BACE1, beta-secretase 1
- BBB, blood brain barrier
- CC, corpus callosum
- CMRglu, cerebral glucose metabolic rate
- COX, complex IV cytochrome c oxidase
- CPT1, carnitine palmitoyltransferase 1
- Cldn11, claudin 11
- Cyp2j6, arachidonic acid epoxygenase
- Cytosolic phospholipase A2
- DHA, docosahexaesnoic acid
- Erbb3, Erb-B2 receptor tyrosine kinase 3
- FDG-PET, 2-[18F]fluoro-2-deoxy-d-glucose
- GFAP, glial fibrillary acidic protein
- H2O2, hydrogen peroxide
- HADHA, hydroxyacyl-CoA dehydrogenase
- HK, hexokinase
- Ketone bodies
- LC MS, liquid chromatography mass spectrometer
- MAG, myelin associated glycoprotein
- MBP, myelin basic protein
- MCT1, monocarboxylate transporter 1
- MIB, mitochondrial isolation buffer
- MOG, myelin oligodendrocyte glycoprotein
- MTL, medial temporal lobe
- Mitochondria
- NEFA, nonesterified fatty acids
- Neurodegeneration
- OCR, oxygen consumption rate
- Olig2, oligodendrocyte transcription factor
- PB, phosphate buffer
- PCC, posterior cingulate
- PCR, polymerase chain reaction
- PDH, pyruvate dehydrogenase
- PEI, polyethyleneimine
- RCR, respiratory control ratio
- ROS, reactive oxygen species
- S1P, sphingosine
- TLDA, TaqMan low density array
- WM, white matter
- WT, wild type
- White matter
- cPLA2, cytosolic phospholipase A2
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Affiliation(s)
- Lauren P Klosinski
- Department of Neuroscience, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA, USA
| | - Jia Yao
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Fei Yin
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | | | | | | | - Eugenia Trushina
- Department of Neurology, Mayo Clinic Rochester, MN, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA
| | - Roberta Diaz Brinton
- Department of Neuroscience, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA, USA; Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA; Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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62
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Pathophysiological Roles of Cyclooxygenases and Prostaglandins in the Central Nervous System. Mol Neurobiol 2015; 53:4754-71. [PMID: 26328537 DOI: 10.1007/s12035-015-9355-3] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 07/07/2015] [Indexed: 01/01/2023]
Abstract
Cyclooxygenases (COXs) oxidize arachidonic acid to prostaglandin (PG) G2 and H2 followed by PG synthases that generates PGs and thromboxane (TX) A2. COXs are divided into COX-1 and COX-2. In the central nervous system, COX-1 is constitutively expressed in neurons, astrocytes, and microglial cells. COX-2 is upregulated in these cells under pathophysiological conditions. In hippocampal long-term potentiation, COX-2, PGE synthase, and PGE2 are induced in post-synaptic neurons. PGE2 acts pre-synaptic EP2 receptor, generates cAMP, stimulates protein kinase A, modulates voltage-dependent calcium channel, facilitates glutamatergic synaptic transmission, and potentiates long-term plasticity. PGD2, PGE2, and PGI2 exhibit neuroprotective effects via Gs-coupled DP1, EP2/EP4, and IP receptors, respectively. COX-2, PGD2, PGE2, PGF2α, and TXA2 are elevated in stroke. COX-2 inhibitors exhibit neuroprotective effects in vivo and in vitro models of stroke, Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis, epilepsy, and schizophrenia, suggesting neurotoxicities of COX products. PGE2, PGF2α, and TXA2 can contribute to the neurodegeneration via EP1, FP, and TP receptors, respectively, which are coupled with Gq, stimulate phospholipase C and cleave phosphatidylinositol diphosphate to produce inositol triphosphate and diacylglycerol. Inositol triphosphate binds to inositol triphosphate receptor in endoplasmic reticulum, releases calcium, and results in increasing intracellular calcium concentrations. Diacylglycerol activates calcium-dependent protein kinases. PGE2 disrupts Ca(2+) homeostasis by impairing Na(+)-Ca(2+) exchange via EP1, resulting in the excess Ca(2+) accumulation. Neither PGE2, PGF2α, nor TXA2 causes neuronal cell death by itself, suggesting that they might enhance the ischemia-induced neurodegeneration. Alternatively, PGE2 is non-enzymatically dehydrated to a cyclopentenone PGA2, which induces neuronal cell death. Although PGD2 induces neuronal apoptosis after a lag time, neither DP1 nor DP2 is involved in the neurotoxicity. As well as PGE2, PGD2 is non-enzymatically dehydrated to a cyclopentenone 15-deoxy-Δ(12,14)-PGJ2, which induces neuronal apoptosis without a lag time. However, neurotoxicities of these cyclopentenones are independent of their receptors. The COX-2 inhibitor inhibits both the anchorage-dependent and anchorage-independent growth of glioma cell lines regardless of COX-2 expression, suggesting that some COX-2-independent mechanisms underlie the antineoplastic effect of the inhibitor. PGE2 attenuates this antineoplastic effect, suggesting that the predominant mechanism is COX-dependent. COX-2 or EP1 inhibitors show anti-neoplastic effects. Thus, our review presents evidences for pathophysiological roles of cyclooxygenases and prostaglandins in the central nervous system.
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Ong WY, Herr DR, Farooqui T, Ling EA, Farooqui AA. Role of sphingomyelinases in neurological disorders. Expert Opin Ther Targets 2015; 19:1725-42. [DOI: 10.1517/14728222.2015.1071794] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Gamba P, Testa G, Gargiulo S, Staurenghi E, Poli G, Leonarduzzi G. Oxidized cholesterol as the driving force behind the development of Alzheimer's disease. Front Aging Neurosci 2015; 7:119. [PMID: 26150787 PMCID: PMC4473000 DOI: 10.3389/fnagi.2015.00119] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 06/03/2015] [Indexed: 12/21/2022] Open
Abstract
Alzheimer’s disease (AD), the most common neurodegenerative disorder associated with dementia, is typified by the pathological accumulation of amyloid Aβ peptides and neurofibrillary tangles (NFT) within the brain. Considerable evidence indicates that many events contribute to AD progression, including oxidative stress, inflammation, and altered cholesterol metabolism. The brain’s high lipid content makes it particularly vulnerable to oxidative species, with the consequent enhancement of lipid peroxidation and cholesterol oxidation, and the subsequent formation of end products, mainly 4-hydroxynonenal and oxysterols, respectively from the two processes. The chronic inflammatory events observed in the AD brain include activation of microglia and astrocytes, together with enhancement of inflammatory molecule and free radical release. Along with glial cells, neurons themselves have been found to contribute to neuroinflammation in the AD brain, by serving as sources of inflammatory mediators. Oxidative stress is intimately associated with neuroinflammation, and a vicious circle has been found to connect oxidative stress and inflammation in AD. Alongside oxidative stress and inflammation, altered cholesterol metabolism and hypercholesterolemia also significantly contribute to neuronal damage and to progression of AD. Increasing evidence is now consolidating the hypothesis that oxidized cholesterol is the driving force behind the development of AD, and that oxysterols are the link connecting the disease to altered cholesterol metabolism in the brain and hypercholesterolemia; this is because of the ability of oxysterols, unlike cholesterol, to cross the blood brain barrier (BBB). The key role of oxysterols in AD pathogenesis has been strongly supported by research pointing to their involvement in modulating neuroinflammation, Aβ accumulation, and cell death. This review highlights the key role played by cholesterol and oxysterols in the brain in AD pathogenesis.
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Affiliation(s)
- Paola Gamba
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin Orbassano, Torino, Italy
| | - Gabriella Testa
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin Orbassano, Torino, Italy
| | - Simona Gargiulo
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin Orbassano, Torino, Italy
| | - Erica Staurenghi
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin Orbassano, Torino, Italy
| | - Giuseppe Poli
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin Orbassano, Torino, Italy
| | - Gabriella Leonarduzzi
- Department of Clinical and Biological Sciences, School of Medicine, University of Turin Orbassano, Torino, Italy
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Ong WY, Farooqui T, Kokotos G, Farooqui AA. Synthetic and natural inhibitors of phospholipases A2: their importance for understanding and treatment of neurological disorders. ACS Chem Neurosci 2015; 6:814-31. [PMID: 25891385 DOI: 10.1021/acschemneuro.5b00073] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Phospholipases A2 (PLA2) are a diverse group of enzymes that hydrolyze membrane phospholipids into arachidonic acid and lysophospholipids. Arachidonic acid is metabolized to eicosanoids (prostaglandins, leukotrienes, thromboxanes), and lysophospholipids are converted to platelet-activating factors. These lipid mediators play critical roles in the initiation, maintenance, and modulation of neuroinflammation and oxidative stress. Neurological disorders including excitotoxicity; traumatic nerve and brain injury; cerebral ischemia; Alzheimer's disease; Parkinson's disease; multiple sclerosis; experimental allergic encephalitis; pain; depression; bipolar disorder; schizophrenia; and autism are characterized by oxidative stress, inflammatory reactions, alterations in phospholipid metabolism, accumulation of lipid peroxides, and increased activities of brain phospholipase A2 isoforms. Several old and new synthetic inhibitors of PLA2, including fatty acid trifluoromethyl ketones; methyl arachidonyl fluorophosphonate; bromoenol lactone; indole-based inhibitors; pyrrolidine-based inhibitors; amide inhibitors, 2-oxoamides; 1,3-disubstituted propan-2-ones and polyfluoroalkyl ketones as well as phytochemical based PLA2 inhibitors including curcumin, Ginkgo biloba and Centella asiatica extracts have been discovered and used for the treatment of neurological disorders in cell culture and animal model systems. The purpose of this review is to summarize information on selective and potent synthetic inhibitors of PLA2 as well as several PLA2 inhibitors from plants, for treatment of oxidative stress and neuroinflammation associated with the pathogenesis of neurological disorders.
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Affiliation(s)
- Wei-Yi Ong
- Department
of Anatomy, National University of Singapore, Singapore 119260, Singapore
| | - Tahira Farooqui
- Department
of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
| | - George Kokotos
- Laboratory
of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis,
Athens 15771, Greece
| | - Akhlaq A. Farooqui
- Department
of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
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Ceramides in Alzheimer's Disease: Key Mediators of Neuronal Apoptosis Induced by Oxidative Stress and Aβ Accumulation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:346783. [PMID: 26090071 PMCID: PMC4458271 DOI: 10.1155/2015/346783] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 05/06/2015] [Accepted: 05/07/2015] [Indexed: 11/17/2022]
Abstract
Alzheimer's disease (AD), the most common chronic and progressive neurodegenerative disorder, is characterized by extracellular deposits of amyloid β-peptides (Aβ) and intracellular deposits of hyperphosphorylated tau (phospho-tau) protein. Ceramides, the major molecules of sphingolipid metabolism and lipid second messengers, have been associated with AD progression and pathology via Aβ generation. Enhanced levels of ceramides directly increase Aβ through stabilization of β-secretase, the key enzyme in the amyloidogenic processing of Aβ precursor protein (APP). As a positive feedback loop, the generated oligomeric and fibrillar Aβ induces a further increase in ceramide levels by activating sphingomyelinases that catalyze the catabolic breakdown of sphingomyelin to ceramide. Evidence also supports important role of ceramides in neuronal apoptosis. Ceramides may initiate a cascade of biochemical alterations, which ultimately leads to neuronal death by diverse mechanisms, including depolarization and permeabilization of mitochondria, increased production of reactive oxygen species (ROS), cytochrome c release, Bcl-2 depletion, and caspase-3 activation, mainly by modulating intracellular signalling, particularly along the pathways related to Akt/PKB kinase and mitogen-activated protein kinases (MAPKs). This review summarizes recent findings related to the role of ceramides in oxidative stress-driven neuronal apoptosis and interplay with Aβ in the cascade of events ending in neuronal degeneration.
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Fonteh AN, Ormseth C, Chiang J, Cipolla M, Arakaki X, Harrington MG. Sphingolipid metabolism correlates with cerebrospinal fluid Beta amyloid levels in Alzheimer's disease. PLoS One 2015; 10:e0125597. [PMID: 25938590 PMCID: PMC4418746 DOI: 10.1371/journal.pone.0125597] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 03/24/2015] [Indexed: 12/14/2022] Open
Abstract
Sphingolipids are important in many brain functions but their role in Alzheimer’s disease (AD) is not completely defined. A major limit is availability of fresh brain tissue with defined AD pathology. The discovery that cerebrospinal fluid (CSF) contains abundant nanoparticles that include synaptic vesicles and large dense core vesicles offer an accessible sample to study these organelles, while the supernatant fluid allows study of brain interstitial metabolism. Our objective was to characterize sphingolipids in nanoparticles representative of membrane vesicle metabolism, and in supernatant fluid representative of interstitial metabolism from study participants with varying levels of cognitive dysfunction. We recently described the recruitment, diagnosis, and CSF collection from cognitively normal or impaired study participants. Using liquid chromatography tandem mass spectrometry, we report that cognitively normal participants had measureable levels of sphingomyelin, ceramide, and dihydroceramide species, but that their distribution differed between nanoparticles and supernatant fluid, and further differed in those with cognitive impairment. In CSF from AD compared with cognitively normal participants: a) total sphingomyelin levels were lower in nanoparticles and supernatant fluid; b) levels of ceramide species were lower in nanoparticles and higher in supernatant fluid; c) three sphingomyelin species were reduced in the nanoparticle fraction. Moreover, three sphingomyelin species in the nanoparticle fraction were lower in mild cognitive impairment compared with cognitively normal participants. The activity of acid, but not neutral sphingomyelinase was significantly reduced in the CSF from AD participants. The reduction in acid sphingomylinase in CSF from AD participants was independent of depression and psychotropic medications. Acid sphingomyelinase activity positively correlated with amyloid β42 concentration in CSF from cognitively normal but not impaired participants. In dementia, altered sphingolipid metabolism, decreased acid sphingomyelinase activity and its lost association with CSF amyloid β42 concentration, underscores the potential of sphingolipids as disease biomarkers, and acid sphingomyelinase as a target for AD diagnosis and/or treatment.
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Affiliation(s)
- Alfred N. Fonteh
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 N El Molino Ave, Pasadena, California, United Sates of America
- * E-mail:
| | - Cora Ormseth
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 N El Molino Ave, Pasadena, California, United Sates of America
| | - Jiarong Chiang
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 N El Molino Ave, Pasadena, California, United Sates of America
| | - Matthew Cipolla
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 N El Molino Ave, Pasadena, California, United Sates of America
| | - Xianghong Arakaki
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 N El Molino Ave, Pasadena, California, United Sates of America
| | - Michael G. Harrington
- Molecular Neurology Program, Huntington Medical Research Institutes, 99 N El Molino Ave, Pasadena, California, United Sates of America
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Sphingosin-1-phosphate Receptor 1: a Potential Target to Inhibit Neuroinflammation and Restore the Sphingosin-1-phosphate Metabolism. Can J Neurol Sci 2015; 42:195-202. [PMID: 25860537 DOI: 10.1017/cjn.2015.19] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Recent evidence suggests that an extreme shift may occur in sphingosine metabolism in neuroinflammatory contexts. Sphingosine 1-phosphate (S1P)-metabolizing enzymes (SMEs) regulate the level of S1P. We recently found that FTY720, a S1P analogue, and SEW2871, a selective S1P receptor 1 (S1P1) agonist, provide protection against neural damage and memory deficit in amyloid beta (Aβ)-injected animals. This study aimed to evaluate the effects of these two analogues on the expression of SMEs as well as their anti-inflammatory roles. METHODS Rats were treated with intracerebral lipopolysaccharide (LPS) or Aβ. Memory impairment was assessed by Morris water maze and the effects of drugs on SMEs as well as inflammatory markers, TNF- α and COX-II, were determined by immunoblotting. RESULTS Aβ and LPS differentially altered the expression profile of SMEs. In Aβ-injected animals, FTY720 and SEW2871 treatments exerted anti-inflammatory effects and restored the expression profile of SMEs, in parallel to our previous findings. In LPS animals however, in spite of anti-inflammatory effects of the two analogues, only FTY720 restored the levels of SMEs and prevented memory deficit. CONCLUSION The observed ameliorating effects of FTY720 and SEW7821 can be partly attributed to the interruption of the vicious cycle of abnormal S1P metabolism and neuro-inflammation. The close imitation of the FTY720 effects by SW2871 in Aβ-induced neuro-inflammation may highlight the attractive role of S1P1 as a potential target to restore S1P metabolism and inhibit inflammatory processes.
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α-Synuclein-induced synapse damage in cultured neurons is mediated by cholesterol-sensitive activation of cytoplasmic phospholipase A2. Biomolecules 2015; 5:178-93. [PMID: 25761116 PMCID: PMC4384118 DOI: 10.3390/biom5010178] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 02/11/2015] [Accepted: 02/19/2015] [Indexed: 12/20/2022] Open
Abstract
The accumulation of aggregated forms of the α-synuclein (αSN) is associated with the pathogenesis of Parkinson's disease (PD) and Dementia with Lewy Bodies. The loss of synapses is an important event in the pathogenesis of these diseases. Here we show that aggregated recombinant human αSN, but not βSN, triggered synapse damage in cultured neurons as measured by the loss of synaptic proteins. Pre-treatment with the selective cytoplasmic phospholipase A2 (cPLA2) inhibitors AACOCF3 and MAFP protected neurons against αSN-induced synapse damage. Synapse damage was associated with the αSN-induced activation of synaptic cPLA2 and the production of prostaglandin E2. The activation of cPLA2 is the first step in the generation of platelet-activating factor (PAF) and PAF receptor antagonists (ginkgolide B or Hexa-PAF) also protect neurons against αSN-induced synapse damage. αSN-induced synapse damage was also reduced in neurons pre-treated with the cholesterol synthesis inhibitor (squalestatin). These results are consistent with the hypothesis that αSN triggered synapse damage via hyperactivation of cPLA2. They also indicate that αSN-induced activation of cPLA2 is influenced by the cholesterol content of membranes. Inhibitors of this pathway that can cross the blood brain barrier may protect against the synapse damage seen during PD.
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Lysophosphatidylcholine increases the neurotoxicity of Alzheimer's amyloid β1-42 peptide: role of oligomer formation. Neuroscience 2015; 292:159-69. [PMID: 25727637 DOI: 10.1016/j.neuroscience.2015.02.034] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 02/16/2015] [Accepted: 02/19/2015] [Indexed: 11/24/2022]
Abstract
Oligomer formation is considered as a critical process for the neurotoxic effects of Alzheimer's amyloid β (Aβ) peptide. Previously we have demonstrated that lysophosphatidylcholine (LPC) increases the oligomer formation of Aβ1-42, the major Aβ peptide found Alzheimer's disease (AD) lesions. In this study, we have investigated whether LPC affects the neurotoxic effects of Aβ1-42 in a neuronal cell line (A1) culture. Dimethyl thiazolyl diphenyl tetrazolium (MTT) assay revealed that up to 10μM concentration, LPC did not affect A1 cell viability. Aβ1-42 decreased the cell viability, and such effect was dose dependently enhanced by LPC. However, neither LPC nor Aβ1-42, alone or in combination increased lactate dehydrogenase (LDH) release from A1 cells after 24-h treatment. Terminal deoxynucleotidyl transferase dUTP-biotin nick-end-labeling (TUNEL) assay showed that LPC increased Aβ1-42-induced apoptotic cell number. To determine the underlying mechanisms, the proteins implicated in apoptosis pathways including Bcl-2- and caspase-family were analyzed by Western blotting. The results demonstrated that Aβ1-42 decreased Bcl-2 in A1 cells at 24h, whereas LPC had no effect at any time point. Both LPC and Aβ1-42 increased Bax level at 24h, and their combined stimulation showed a synergistic effect. Similar synergistic effect of LPC and Aβ1-42 on caspase9 activation was observed. Dot blot immunoassay and Western blotting showed that LPC augmented Aβ1-42 oligomer formation in cell culture medium. Removing LPC-induced early-formed Aβ1-42 oligomer from the culture medium by immunoprecipitation decreased active caspase9 level and neurotoxicity, as revealed by Western blotting and MTT assay. Furthermore, dihydroethidium (DHE) assay showed that Aβ1-42 increased reactive oxygen species level in A1 cells, such effect was further enhanced by LPC. Thus, our results demonstrated that LPC increased the oligomer formation process of Aβ1-42 peptide in culture condition, and consequently increased apoptotic neuronal death. Such process might be important for the pathogenesis of AD, and inhibition of LPC generation could be a therapeutic target for the disease.
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Tabassum S, Sheikh AM, Yano S, Ikeue T, Handa M, Nagai A. A carboxylated Zn-phthalocyanine inhibits fibril formation of Alzheimer's amyloid β peptide. FEBS J 2014; 282:463-76. [PMID: 25404240 DOI: 10.1111/febs.13151] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 11/07/2014] [Accepted: 11/14/2014] [Indexed: 12/31/2022]
Abstract
Amyloid β (Aβ), a 39-42 amino acid peptide derived from amyloid precursor protein, is deposited as fibrils in Alzheimer's disease brains, and is considered to play a major role in the pathogenesis of the disease. We have investigated the effects of a water-soluble Zn-phthalocyanine, ZnPc(COONa)₈, a macrocyclic compound with near-infrared optical properties, on Aβ fibril formation in vitro. A thioflavin T fluorescence assay showed that ZnPc(COONa)₈ significantly inhibited Aβ fibril formation, increasing the lag time and dose-dependently decreasing the plateau level of fibril formation. Moreover, it destabilized pre-formed Aβ fibrils, resulting in an increase in low-molecular-weight species. After fibril formation in the presence of ZnPc(COONa)₈, immunoprecipitation of Aβ₁₋₄₂ using Aβ-specific antibody followed by near-infrared scanning demonstrated binding of ZnPc(COONa)₈ to Aβ₁₋₄₂. A study using the hydrophobic fluorescent probe 8-anilino-1-naphthalenesulfonic acid showed that ZnPc(COONa)8 decreased the hydrophobicity during Aβ₁₋₄₂ fibril formation. CD spectroscopy showed an increase in the α helix structure and a decrease in the β sheet structure of Aβ₁₋₄₀ in fibril-forming buffer containing ZnPc(COONa)₈. SDS/PAGE and a dot-blot immunoassay showed that ZnPc(COONa)₈ delayed the disappearance of low-molecular-weight species and the appearance of higher-molecular-weight oligomeric species of Aβ₁₋₄₂. A cell viability assay showed that ZnPc(COONa)₈ was not toxic to a neuronal cell line (A1), but instead protected A1 cells against Aβ₁₋₄₂-induced toxicity. Overall, our results indicate that ZnPc(COONa)₈ binds to Aβ and decreases the hydrophobicity, and this change is unfavorable for Aβ oligomerization and fibril formation.
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Affiliation(s)
- Shatera Tabassum
- Department of Laboratory Medicine, Shimane University School of Medicine, Izumo, Japan
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Wang SH, Huang Y, Yuan Y, Xia WQ, Wang P, Huang R. LDL receptor knock-out mice show impaired spatial cognition with hippocampal vulnerability to apoptosis and deficits in synapses. Lipids Health Dis 2014; 13:175. [PMID: 25413784 PMCID: PMC4258039 DOI: 10.1186/1476-511x-13-175] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 11/11/2014] [Indexed: 11/30/2022] Open
Abstract
Background Evidence from clinical studies support the fact that abnormal cholesterol metabolism in the brain leads to progressive cognitive dysfunction. The low-density lipoprotein receptor (LDLR) is well-known for its role in regulating cholesterol metabolism. Whether LDLR involved in this impaired cognition and the potential mechanisms that underlie this impairment are unknown. Methods Twelve-month-old Ldlr-/- mice (n = 10) and wild-type littermates C57BL/6 J (n = 14) were subjected to the Morris water maze test. At 1 week after completion of the behavioural testing, all of the animals were sacrificed for analysis of synaptic and apoptotic markers. Results The plasma cholesterol concentration of Ldlr-/- mice was increased moderately when compared with C57BL/6 J mice (P < 0.05). Behavioural testing revealed that Ldlr-/- mice displayed impaired spatial memory, and moreover, the expression levels of synaptophysin and the number of synaptophysin-immunoreactive presynaptic boutons in the hippocampal CA1 and dentate gyrus were decreased (all P < 0.05). Ultrastructural changes in the dentate gyrus were observed using transmission electron microscopy. Furthermore, apoptosis in the hippocampus of Ldlr-/- mice was revealed based on elevation, at both the mRNA and protein levels, of the ratio of Bax/Bcl-2 expression (all P < 0.05)and an increase in activated-caspase3 protein level (P < 0.05). Conclusion LDLR deficiency contributes to impaired spatial cognition. This most likely occurs via negative effects that promote apoptosis and synaptic deficits in the hippocampus.
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Affiliation(s)
- Shao-hua Wang
- Department of Endocrinology, ZhongDa Hospital of Southeast University, No,87 DingJiaQiao Road, Nanjing 210009, PR China.
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Pathological roles of ceramide and its metabolites in metabolic syndrome and Alzheimer's disease. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1841:793-8. [DOI: 10.1016/j.bbalip.2013.08.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 07/30/2013] [Accepted: 08/02/2013] [Indexed: 02/03/2023]
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Liu Q, Zhang J. Lipid metabolism in Alzheimer's disease. Neurosci Bull 2014; 30:331-45. [PMID: 24733655 DOI: 10.1007/s12264-013-1410-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 02/25/2014] [Indexed: 12/14/2022] Open
Abstract
Lipids play crucial roles in cell signaling and various physiological processes, especially in the brain. Impaired lipid metabolism in the brain has been implicated in neurodegenerative diseases, such as Alzheimer's disease (AD), and other central nervous system insults. The brain contains thousands of lipid species, but the complex lipid compositional diversity and the function of each of lipid species are currently poorly understood. This review integrates current knowledge about major lipid changes with the molecular mechanisms that underlie AD pathogenesis.
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Affiliation(s)
- Qiang Liu
- CAS Key Laboratory of Brain Function and Disease and School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China,
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Yang Y, Wang M, Lv B, Ma R, Hu J, Dun Y, Sun S, Li G. Sphingosine Kinase-1 Protects Differentiated N2a Cells Against Beta-Amyloid25–35-Induced Neurotoxicity Via the Mitochondrial Pathway. Neurochem Res 2014; 39:932-40. [DOI: 10.1007/s11064-014-1290-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 03/09/2014] [Accepted: 03/20/2014] [Indexed: 12/14/2022]
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Involvement of TRPV4 channels in Aβ40-induced hippocampal cell death and astrocytic Ca2+ signalling. Neurotoxicology 2014; 41:64-72. [DOI: 10.1016/j.neuro.2014.01.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 01/09/2014] [Accepted: 01/12/2014] [Indexed: 11/18/2022]
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Sun GY, Chuang DY, Zong Y, Jiang J, Lee JCM, Gu Z, Simonyi A. Role of cytosolic phospholipase A2 in oxidative and inflammatory signaling pathways in different cell types in the central nervous system. Mol Neurobiol 2014; 50:6-14. [PMID: 24573693 DOI: 10.1007/s12035-014-8662-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 02/11/2014] [Indexed: 12/30/2022]
Abstract
Phospholipases A(2) (PLA(2)s) are important enzymes for the metabolism of fatty acids in membrane phospholipids. Among the three major classes of PLA(2)s in the mammalian system, the group IV calcium-dependent cytosolic PLA(2) alpha (cPLA(2)α) has received the most attention because it is widely expressed in nearly all mammalian cells and its active participation in cell metabolism. Besides Ca(2+) binding to its C2 domain, this enzyme can undergo a number of cell-specific post-translational modifications, including phosphorylation by protein kinases, S-nitrosylation through interaction with nitric oxide (NO), as well as interaction with other proteins and lipid molecules. Hydrolysis of phospholipids by cPLA(2) yields two important lipid mediators, arachidonic acid (AA) and lysophospholipids. While AA is known to serve as a substrate for cyclooxygenases and lipoxygenases, which are enzymes for the synthesis of eicosanoids and leukotrienes, lysophospholipids are known to possess detergent-like properties capable of altering microdomains of cell membranes. An important feature of cPLA(2) is its link to cell surface receptors that stimulate signaling pathways associated with activation of protein kinases and production of reactive oxygen species (ROS). In the central nervous system (CNS), cPLA(2) activation has been implicated in neuronal excitation, synaptic secretion, apoptosis, cell-cell interaction, cognitive and behavioral function, oxidative-nitrosative stress, and inflammatory responses that underline the pathogenesis of a number of neurodegenerative diseases. However, the types of extracellular agonists that target intracellular signaling pathways leading to cPLA(2) activation among different cell types and under different physiological and pathological conditions have not been investigated in detail. In this review, special emphasis is given to metabolic events linking cPLA(2) to activation in neurons, astrocytes, microglial cells, and cerebrovascular cells. Understanding the molecular mechanism(s) for regulation of this enzyme is deemed important in the development of new therapeutic targets for the treatment and prevention of neurodegenerative diseases.
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Affiliation(s)
- Grace Y Sun
- Biochemistry Department, University of Missouri, 117 Schweitzer Hall, Columbia, MO, 65211, USA,
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Dinkins MB, Dasgupta S, Wang G, Zhu G, Bieberich E. Exosome reduction in vivo is associated with lower amyloid plaque load in the 5XFAD mouse model of Alzheimer's disease. Neurobiol Aging 2014; 35:1792-800. [PMID: 24650793 DOI: 10.1016/j.neurobiolaging.2014.02.012] [Citation(s) in RCA: 335] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 02/06/2014] [Accepted: 02/10/2014] [Indexed: 11/19/2022]
Abstract
We present evidence here that exosomes stimulate aggregation of amyloid beta (Aβ)1-42 in vitro and in vivo and interfere with uptake of Aβ by primary cultured astrocytes and microglia in vitro. Exosome secretion is prevented by the inhibition of neutral sphingomyelinase 2 (nSMase2), a key regulatory enzyme generating ceramide from sphingomyelin, with GW4869. Using the 5XFAD mouse, we show that intraperitoneal injection of GW4869 reduces the levels of brain and serum exosomes, brain ceramide, and Aβ1-42 plaque load. Reduction of total Aβ1-42 as well as number of plaques in brain sections was significantly greater (40% reduction) in male than female mice. Our results suggest that GW4869 reduces amyloid plaque formation in vivo by preventing exosome secretion and identifies nSMase2 as a potential drug target in AD by interfering with exosome secretion.
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Affiliation(s)
- Michael B Dinkins
- Institute of Molecular Medicine and Genetics, Georgia Regents University, Augusta, GA, USA
| | - Somsankar Dasgupta
- Institute of Molecular Medicine and Genetics, Georgia Regents University, Augusta, GA, USA
| | - Guanghu Wang
- Institute of Molecular Medicine and Genetics, Georgia Regents University, Augusta, GA, USA
| | - Gu Zhu
- Institute of Molecular Medicine and Genetics, Georgia Regents University, Augusta, GA, USA
| | - Erhard Bieberich
- Institute of Molecular Medicine and Genetics, Georgia Regents University, Augusta, GA, USA.
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79
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Panchal M, Gaudin M, Lazar AN, Salvati E, Rivals I, Ayciriex S, Dauphinot L, Dargère D, Auzeil N, Masserini M, Laprévote O, Duyckaerts C. Ceramides and sphingomyelinases in senile plaques. Neurobiol Dis 2014; 65:193-201. [PMID: 24486621 DOI: 10.1016/j.nbd.2014.01.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/10/2014] [Accepted: 01/14/2014] [Indexed: 12/14/2022] Open
Abstract
The senile plaque is a hallmark lesion of Alzheimer disease (AD). We compared, without a priori, the lipidome of the senile plaques and of the adjacent plaque-free neuropil. The analysis by liquid chromatography coupled with electrospray ionization mass spectrometry revealed that laser microdissected senile plaques were enriched in saturated ceramides Cer(d18:1/18:0) and Cer(d18:1/20:0) by 33 and 78% respectively with respect to the surrounding neuropil. This accumulation of ceramides was not explained by their affinity for Aβ deposits: no interaction between ceramide-liposomes and Aβ fibrils was observed in vitro by surface plasmon resonance and fluorescent ceramide-liposomes showed no affinity for the senile plaques in AD brain tissue. Accumulation of ceramides could be, at least partially, the result of a local production by acid and neutral sphingomyelinases that we found to be present in the corona of the senile plaques.
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Affiliation(s)
- Maï Panchal
- Laboratoire de Neuropathologie Escourolle, Hôpital de la Salpêtrière, AP-HP, Paris, France; Centre de recherche de l'ICM, UPMC, INSERM UMR S 975, CNRS UMR 7225, France
| | - Mathieu Gaudin
- Chimie-Toxicologie Analytique et Cellulaire, EA 4463, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, PRES Sorbonne Paris Cité, France; Division Métabolisme, Technologie Servier, Orléans, France
| | - Adina N Lazar
- Laboratoire de Neuropathologie Escourolle, Hôpital de la Salpêtrière, AP-HP, Paris, France; Centre de recherche de l'ICM, UPMC, INSERM UMR S 975, CNRS UMR 7225, France; Equipe de Statistique Appliquée, ESPCI Paris Tech, Paris, France.
| | | | - Isabelle Rivals
- Department of Health Sciences and Nanomedicine Center, University of Milano Bicocca, Monza, Italy
| | - Sophie Ayciriex
- Chimie-Toxicologie Analytique et Cellulaire, EA 4463, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, PRES Sorbonne Paris Cité, France
| | - Luce Dauphinot
- Centre de recherche de l'ICM, UPMC, INSERM UMR S 975, CNRS UMR 7225, France
| | - Delphine Dargère
- Chimie-Toxicologie Analytique et Cellulaire, EA 4463, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, PRES Sorbonne Paris Cité, France
| | - Nicolas Auzeil
- Chimie-Toxicologie Analytique et Cellulaire, EA 4463, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, PRES Sorbonne Paris Cité, France
| | | | - Olivier Laprévote
- Chimie-Toxicologie Analytique et Cellulaire, EA 4463, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes, PRES Sorbonne Paris Cité, France; Laboratoire de Toxicologie Biologique, Hôpital Lariboisière, AP-HP, Paris, France
| | - Charles Duyckaerts
- Laboratoire de Neuropathologie Escourolle, Hôpital de la Salpêtrière, AP-HP, Paris, France; Centre de recherche de l'ICM, UPMC, INSERM UMR S 975, CNRS UMR 7225, France; Equipe de Statistique Appliquée, ESPCI Paris Tech, Paris, France
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Ceccom J, Loukh N, Lauwers-Cances V, Touriol C, Nicaise Y, Gentil C, Uro-Coste E, Pitson S, Maurage CA, Duyckaerts C, Cuvillier O, Delisle MB. Reduced sphingosine kinase-1 and enhanced sphingosine 1-phosphate lyase expression demonstrate deregulated sphingosine 1-phosphate signaling in Alzheimer's disease. Acta Neuropathol Commun 2014; 2:12. [PMID: 24468113 PMCID: PMC3912487 DOI: 10.1186/2051-5960-2-12] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 01/18/2014] [Indexed: 12/14/2022] Open
Abstract
Background The accumulation of beta amyloid (Aβ) peptides, a hallmark of Alzheimer’s disease (AD) is related to mechanisms leading to neurodegeneration. Among its pleiotropic cellular effects, Aβ accumulation has been associated with a deregulation of sphingolipid metabolism. Sphingosine 1-phosphate (S1P) derived from sphingosine is emerging as a critical lipid mediator regulating various biological activities including cell proliferation, survival, migration, inflammation, or angiogenesis. S1P tissue level is low and kept under control through equilibrium between its synthesis mostly governed by sphingosine kinase-1 (SphK1) and its degradation by sphingosine 1-phosphate lyase (SPL). We have previously reported that Aβ peptides were able to decrease the activity of SphK1 in cell culture models, an effect that could be blocked by the prosurvival IGF-1/IGF-1R signaling. Results Herein, we report for the first time the expression of both SphK1 and SPL by immunohistochemistry in frontal and entorhinal cortices from 56 human AD brains. Immunohistochemical analysis revealed a decreased expression of SphK1 and an increased expression of SPL both correlated to amyloid deposits in the entorhinal cortex. Otherwise, analysis of brain tissue extracts showed a decrease of SphK1 expression in AD brains whereas SPL expression was increased. The content of IGF-1R, an activator of SphK1, was found decreased in AD brains as well as S1P1, the major receptor for S1P. Conclusions Collectively, these results highlight the importance of S1P in AD suggesting the existence of a global deregulation of S1P signaling in this disease from its synthesis by SphK1 and degradation by SPL to its signaling by the S1P1 receptor.
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81
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Couttas TA, Kain N, Daniels B, Lim XY, Shepherd C, Kril J, Pickford R, Li H, Garner B, Don AS. Loss of the neuroprotective factor Sphingosine 1-phosphate early in Alzheimer's disease pathogenesis. Acta Neuropathol Commun 2014; 2:9. [PMID: 24456642 PMCID: PMC3906863 DOI: 10.1186/2051-5960-2-9] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 01/20/2014] [Indexed: 01/09/2023] Open
Abstract
Background The greatest genetic risk factor for late-onset Alzheimer's disease (AD) is the ϵ4 allele of Apolipoprotein E (ApoE). ApoE regulates secretion of the potent neuroprotective signaling lipid Sphingosine 1-phosphate (S1P). S1P is derived by phosphorylation of sphingosine, catalysed by sphingosine kinases 1 and 2 (SphK1 and 2), and SphK1 positively regulates glutamate secretion and synaptic strength in hippocampal neurons. S1P and its receptor family have been subject to intense pharmacological interest in recent years, following approval of the immunomodulatory drug Fingolimod, an S1P mimetic, for relapsing multiple sclerosis. Results We quantified S1P levels in six brain regions that are differentially affected by AD pathology, in a cohort of 34 post-mortem brains, divided into four groups based on Braak neurofibrillary tangle staging. S1P declined with increasing Braak stage, and this was most pronounced in brain regions most heavily affected by AD pathology. The S1P/sphingosine ratio was 66% and 64% lower in Braak stage III/IV hippocampus (p = 0.010) and inferior temporal cortex (p = 0.014), respectively, compared to controls. In accordance with this change, both SphK1 and SphK2 activity declined with increasing Braak pathology in the hippocampus (p = 0.032 and 0.047, respectively). S1P/sphingosine ratio was 2.5-fold higher in hippocampus of ApoE2 carriers compared to ApoE4 carriers, and multivariate regression showed a significant association between APOE genotype and hippocampal S1P/sphingosine (p = 0.0495), suggesting a new link between APOE genotype and pre-disposition to AD. Conclusions This study demonstrates loss of S1P and sphingosine kinase activity early in AD pathogenesis, and prior to AD diagnosis. Our findings establish a rationale for further exploring S1P receptor pharmacology in the context of AD therapy.
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82
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Haughey NJ, Zhu X, Bandaru VVR. A biological perspective of CSF lipids as surrogate markers for cognitive status in HIV. J Neuroimmune Pharmacol 2013; 8:1136-46. [PMID: 24203462 PMCID: PMC3909934 DOI: 10.1007/s11481-013-9506-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 10/03/2013] [Indexed: 12/14/2022]
Abstract
The development and application of biomarkers to neurodegenerative diseases has become increasingly important in clinical practice and therapeutic trials. While substantial progress has been made at the basic science level in understanding the pathophysiology of HIV-Associated Neurocognitive Disorders (HAND), there are significant limitations in our current ability to predict the onset or trajectory of disease, and to accurately determine the effects of therapeutic interventions. Thus, the development of objective biomarkers is critical to further our understanding and treatment of HAND. In recent years, biomarker discovery efforts have largely been driven forward through the implementation of multiple "omics" approaches that include (but are not restricted to): Lipidomics, proteomics, metabolomics, genomics, transcriptomics, and advances in brain imaging approaches such as functional connectomics. In this paper we summarize our progress to date on lipidomic approaches to biomarker discovery, discuss how these data have influenced basic research on the neuropathology of HAND, and implications for the development of therapeutics that target metabolic pathways involved in lipid handling.
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Affiliation(s)
- Norman J Haughey
- Department of Neurology, Division of Neuroimmunology and Neurological Infections, The Johns Hopkins University School of Medicine, Pathology 517, 600 North Wolfe Street, Baltimore, MD, 21287, USA,
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Sagy-Bross C, Hadad N, Levy R. Cytosolic phospholipase A2α upregulation mediates apoptotic neuronal death induced by aggregated amyloid-β peptide1-42. Neurochem Int 2013; 63:541-50. [PMID: 24044897 DOI: 10.1016/j.neuint.2013.09.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 09/01/2013] [Accepted: 09/06/2013] [Indexed: 10/26/2022]
Abstract
Increased cytosolic phospholipase A2α (cPLA2α) immunoreactivity and transcript were observed in Alzheimer's disease (AD) brain associated with amyloid deposits. Thus, the present study examined whether cPLA2α upregulation participate in cortical neuron damage induced by aggregated Aβ1-42 and determined its role in the signaling events leading to damage, using an antisense technology. Exposure of primary cortical neurons to 1μM aggregated Aβ1-42 for 24h induced up-regulation and activation of cPLA2α and apoptotic cell death of about 30% as detected by: cell count, MTT reduction, caspases-3 and -8 activation, DAPI and TUNEL staining, that were prevented by inhibition of cPLA2α up-regulation and activity in the presence of antisense against cPLA2α (AS). cPLA2α was rapidly activated upon addition of aggregated Aβ1-42, as determined by its phosphorylated form on serine 505, and this activity was dependent on NADPH oxidase activity. NOX2- and NOX4-NADPH oxidase upregulation at 24h of aggregated Aβ1-42 exposure was not affected by the presence of AS, but superoxide production was reduced, probably due to NOX2 inhibition. cPLA2α upregulation led to activation of neutral sphingomyelinase (N-SMase) as its activity was inhibited in the presence of AS, and could be restored by addition of arachidonic acid. Addition of ceramide analog induced caspase-8 activation leading to caspase-3 activation and apoptotic neuronal death. In conclusion, our results suggest that cPLA2α activity plays a crucial role in the signaling cascade leading to apoptotic neuronal death by aggregated Aβ1-42 probably via activation of N-SMase, ceramide production and caspases-3 and -8.
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Affiliation(s)
- Chen Sagy-Bross
- Immunology and Infectious Diseases Laboratory, Clinical Biochemistry Department, Faculty of Health Sciences, Ben-Gurion University of the Negev, Soroka University Medical Center, Beer-Sheva, Israel
| | - Nurit Hadad
- Immunology and Infectious Diseases Laboratory, Clinical Biochemistry Department, Faculty of Health Sciences, Ben-Gurion University of the Negev, Soroka University Medical Center, Beer-Sheva, Israel
| | - Rachel Levy
- Immunology and Infectious Diseases Laboratory, Clinical Biochemistry Department, Faculty of Health Sciences, Ben-Gurion University of the Negev, Soroka University Medical Center, Beer-Sheva, Israel.
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84
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Alessenko AV. The potential role for sphingolipids in neuropathogenesis of Alzheimer’s disease. BIOCHEMISTRY MOSCOW-SUPPLEMENT SERIES B-BIOMEDICAL CHEMISTRY 2013. [DOI: 10.1134/s1990750813020029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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85
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Asle-Rousta M, Kolahdooz Z, Oryan S, Ahmadiani A, Dargahi L. FTY720 (fingolimod) attenuates beta-amyloid peptide (Aβ42)-induced impairment of spatial learning and memory in rats. J Mol Neurosci 2013; 50:524-32. [PMID: 23435938 DOI: 10.1007/s12031-013-9979-6] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 02/08/2013] [Indexed: 12/29/2022]
Abstract
Imbalanced lipid metabolism and increase in the ceramide-to-S1P ratio in the brain have been postulated to play a role in amyloidogenesis, neuroinflammatory reactions, and neuronal apoptosis in Alzheimer's disease (AD) pathology. FTY720, the immunomodulatory sphingosine 1-phosphate (S1P) analog, has recently gained interest because of its CNS-directed effects. In addition to its immunomodulatory functions in multiple sclerosis, FTY720 possesses anti-inflammatory and neuroprotective roles in different cerebral ischemia models. In the present study, we examined the effects of FTY720 in a rat model of AD. Memory deficit was induced by bilateral intrahippocampus injection of beta-amyloid peptide (Aβ(42)) and examined through the Morris water maze test. The extent of histological injury in the hippocampus and the activation of caspase-3 were determined respectively by Nissl staining and Western blotting. Chronic daily administration of FTY720 (1 mg/kg, i.p., 14 days) significantly attenuated the Aβ(42)-induced learning and memory impairment and prevented the hippocampus neuronal damage as well as caspase-3 activation. These data show for the first time that FTY720 has a beneficial effect in restoring memory loss in Aβ(42)-induced neurotoxicity and also suggest that S1P receptors and signaling pathways may provide a potential target for the treatment of AD.
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Affiliation(s)
- Masoumeh Asle-Rousta
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Evin, Tehran, 19615-1178, Iran
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86
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Liu L, Martin R, Chan C. Palmitate-activated astrocytes via serine palmitoyltransferase increase BACE1 in primary neurons by sphingomyelinases. Neurobiol Aging 2013; 34:540-50. [PMID: 22727944 PMCID: PMC3459302 DOI: 10.1016/j.neurobiolaging.2012.05.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 04/27/2012] [Accepted: 05/26/2012] [Indexed: 10/28/2022]
Abstract
Astrocytes play a critical role in neurodegenerative diseases, including Alzheimer's disease (AD). Previously, we showed that saturated free fatty acid, palmitic acid (PA), upregulates β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) level and amyloidogenesis in primary rat neurons mediated by astrocytes. However, the molecular mechanisms by which conditioned media from PA-treated astrocytes upregulates BACE1 level in neurons are unknown. This study demonstrates that serine palmitoyltransferase (SPT) in the astrocytes increases ceramide levels, which enhances the release of cytokines that mediate the activation of neural and acidic sphingomyelinase (SMase) in the neurons, to propagate the deleterious effects of PA (i.e., BACE1 upregulation). In support of the relevance of SPT in AD, our laboratory recently measured and found SPT levels to be significantly upregulated in AD brains as compared with controls. Cytokines, namely tumor necrosis factor-α and interleukin-1β, released into the conditioned media of PA-treated astrocytes activate neural and acidic SMase in the neurons. Neutralizing the cytokines in the PA-treated astrocyte conditioned media reduced BACE1 upregulation. However, inhibiting SPT in the astrocytes decreased the levels of both tumor necrosis factor-α and interleukin-1β in the conditioned media, which in turn reduced the SMase activities and BACE1 level in primary neurons. Thus, our results suggest that the activation of the astrocytes by PA is mediated by SPT, and the activated astrocytes increases BACE1 level in the neurons; the latter is mediate by the SMases.
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Affiliation(s)
- Li Liu
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824
| | - Rebecca Martin
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824
| | - Christina Chan
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824
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87
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Shen YE, Wang Y, Yu GC, Liu C, Zhang ZY, Zhang LM. Effects of edaravone on amyloid-β precursor protein processing in SY5Y-APP695 cells. Neurotox Res 2013; 24:139-47. [PMID: 23325603 DOI: 10.1007/s12640-012-9370-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 12/18/2012] [Accepted: 12/21/2012] [Indexed: 01/09/2023]
Abstract
Previous reports have revealed that reactive oxygen species (ROS) is involved in the development of Alzheimer's disease (AD), and recent studies indicate that free radical-generating systems can regulate amyloid-β precursor protein (APP) processing. Edaravone is a novel free radical scavenger currently used to reduce cerebral damages after acute cerebral infarction. In the present study, we used SH-SY5Y cells stably transfected with the human "Swedish" APP mutation APP695 (SY5Y-APP695swe) as an in vitro model to investigate the effect of edaravone on APP processing. The result showed that edaravone treatment for 24 h down-regulated β-amyloid (Aβ) production in a dose-dependent manner. Moreover, edaravone modulated APP processing by increasing α-secretase-derived APP fragments and decreasing β-secretase-derived APP fragments. In addition, the mRNA and protein levels of insulin degrading enzyme (IDE) and neprilysin (NEP), two key Aβ degrading enzymes, were not changed after edaravone administration. Taken together, our data suggested that edaravone played an important role in regulating Aβ production by enhancing the non-amyloidogenic pathway and inhibiting the amyloidogenic pathway. Thus, edaravone may be potentially useful for treating Alzheimer's disease (AD).
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Affiliation(s)
- Yue-E Shen
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, 23 You Zheng Steet, Nan Gang District, 150001 Harbin, China
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Kornhuber J, Tripal P, Gulbins E, Muehlbacher M. Functional inhibitors of acid sphingomyelinase (FIASMAs). Handb Exp Pharmacol 2013:169-186. [PMID: 23579455 DOI: 10.1007/978-3-7091-1368-4_9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Sphingolipids are not only structural components of biological membranes, but also play an important role in cellular signalling and, thus, are involved in cell proliferation and differentiation but also stress and cell death. It is therefore of great clinical relevance to define inhibitors of the enzymes involved in sphingolipid metabolism. Here, we describe the state of the art of functional inhibitors of the acid sphingomyelinase. The acid sphingomyelinase converts sphingomyelin to ceramide, a compound often involved in cell stress. We describe the structural and physicochemical properties, the distribution, the pharmacokinetics, the pharmocodynamics and the clinical use of direct and functional inhibitors of the acid sphingomyelinase.
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Affiliation(s)
- Johannes Kornhuber
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen, Schwabachanlage 6, D 91054 Erlangen, Germany.
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89
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Li PL, Zhang Y. Cross talk between ceramide and redox signaling: implications for endothelial dysfunction and renal disease. Handb Exp Pharmacol 2013:171-97. [PMID: 23563657 DOI: 10.1007/978-3-7091-1511-4_9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent studies have demonstrated that cross talk between ceramide and redox signaling modulates various cell activities and functions and contributes to the development of cardiovascular diseases and renal dysfunctions. Ceramide triggers the generation of reactive oxygen species (ROS) and increases oxidative stress in many mammalian cells and animal models. On the other hand, inhibition of ROS-generating enzymes or treatment of antioxidants impairs sphingomyelinase activation and ceramide production. As a mechanism, ceramide-enriched signaling platforms, special cell membrane rafts (MR) (formerly lipid rafts), provide an important microenvironment to mediate the cross talk of ceramide and redox signaling to exert a corresponding regulatory role on cell and organ functions. In this regard, activation of acid sphingomyelinase and generation of ceramide mediate the formation of ceramide-enriched membrane platforms, where transmembrane signals are transmitted or amplified through recruitment, clustering, assembling, or integration of various signaling molecules. A typical such signaling platform is MR redox signaling platform that is centered on ceramide production and aggregation leading to recruitment and assembling of NADPH oxidase to form an active complex in the cell plasma membrane. This redox signaling platform not only conducts redox signaling or regulation but also facilitates a feedforward amplification of both ceramide and redox signaling. In addition to this membrane MR redox signaling platform, the cross talk between ceramide and redox signaling may occur in other cell compartments. This book chapter focuses on the molecular mechanisms, spatial-temporal regulations, and implications of this cross talk between ceramide and redox signaling, which may provide novel insights into the understanding of both ceramide and redox signaling pathways.
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Affiliation(s)
- Pin-Lan Li
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA.
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90
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Hyperphosphorylation of tau by GSK-3β in Alzheimer’s disease: The interaction of Aβ and sphingolipid mediators as a therapeutic target. Transl Neurosci 2013. [DOI: 10.2478/s13380-013-0144-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
AbstractAlzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by the extracellular deposits of β amyloid peptides (Aβ) in senile plaques, and intracellular aggregates of hyperphosphorylated tau in neurofibrillary tangles (NFT). Although accumulation of Aβ has been long considered a leading hypothesis in the disease pathology, it is increasingly evident that the role hyperphosphorylation of tau in destabilization of microtubule assembly and disturbance of axonal transport is equally detrimental in the neurodegenerative process. The main kinase involved in phosphorylation of tau is glycogen-synthase kinase 3-beta (GSK-3β). Intracellular accumulation of Aβ also likely induces increase in hyperphosphorylated tau by a mechanism dependent on GSK-3β. In addition, Aβ affects production of ceramides, the major sphingolipids in mammalian cells, by acting on sphingomyelinases, enzymes responsible for the catabolic formation of ceramides from the sphingomyelin. Generated ceramides in turn increase production of Aβ by acting on β-secretase, a key enzyme in the proteolytic processing of the amyloid precursor protein (APP), altogether leading to a ceramide-Aβ-hyperphosphorylated tau cascade that ends in neuronal death. Modulators and inhibitors acting on members of this devastating cascade are considered as potential targets for AD therapy. There is still no adequate treatment for AD patients. Novel therapeutic strategies increasingly consider the combination of multiple targets and interactions among the key members of implicated molecular pathways. This review summarizes recent findings and therapeutic perspectives in the pathology and treatment of AD, with the emphasis on the interplay between hyperphosphorylated tau, amyloid β, and sphingolipid mediators.
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91
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Alessenko A. The potential role for sphingolipids in neuropathogenesis of Alzheimer’s disease. ACTA ACUST UNITED AC 2013. [DOI: 10.18097/pbmc20135901025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The review discusses the functional role of sphingolipids in the pathogenesis of Alzheimer's disease. Certain evidence exist that the imbalance of sphingolipids such as sphingomyelin, ceramide, sphingosine, sphingosine-1-phosphate and galactosylceramide in the brain of animals and humans, in the cerebrospinal fluid and blood plasma of patients with Alzheimer's disease play a crucial role in neuronal function by regulating growth, differentiation and cell death in CNS. Activation of sphingomyelinase, which leads to the accumulation of the proapoptotic agent, ceramide, can be considered as a new mechanism for AD and may be a prerequisite for the treatment of this disease by using drugs that inhibit sphingomyelinase activity. The role of sphingolipids as biomarkers for the diagnosis of the early stage of Alzheimer's disease and monitoring the effectiveness of treatment with new drugs is discussed.
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Affiliation(s)
- A.V. Alessenko
- N.M. Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences
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92
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93
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van Echten-Deckert G, Walter J. Sphingolipids: Critical players in Alzheimer’s disease. Prog Lipid Res 2012; 51:378-93. [DOI: 10.1016/j.plipres.2012.07.001] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 07/06/2012] [Indexed: 12/20/2022]
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94
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Ha J, Zhao L, Zhao Q, Yao J, Zhu BB, Lu N, Ke X, Yang HY, Li Z, You QD, Guo QL. Oroxylin A improves the sensitivity of HT-29 human colon cancer cells to 5-FU through modulation of the COX-2 signaling pathway. Biochem Cell Biol 2012; 90:521-31. [DOI: 10.1139/o2012-005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
5-Fluorouracil (5-FU) is a principal drug for the treatment of colorectal cancer. Due to its low response and high toxicity, synergistic effects of 5-FU in combination with other drugs have been widely researched. This study investigated whether oroxylin A improved the sensitivity of HT-29 human colon cancer cells to 5-FU. A correlation between COX-2 inhibition by oroxylin A and a synergistic effect of 5-FU on the growth of HT-29 cells was observed, and a COX-2 pathway for this effect was recognized; oroxylin A evidently elevated the level of reactive oxygen species in HT-29 cells, which subsequently inhibited COX-2 expression and enhanced the susceptibility of HT-29 cells to 5-FU. Likely also related to COX-2 inhibition, oroxylin A decreased PGE2 levels in HT-29 cells. The synergistic effect of 5-FU induced by oroxylin A was also found in the suppression of Bcl-2 and in the activation of P53, Bax, PARP, and procaspase-3 proteins in HT-29 cells. Ultimately, a combination of 5-FU with oroxylin A significantly reduced the growth of HT-29 tumors in nude mice compared with treatment with 5-FU or oroxylin A alone. In conclusion, a combination of 5-FU and oroxylin A has a significant synergistic effect in the inhibition of HT-29 cell proliferation in vitro and controls HT-29 tumor growth in vivo. This synergistic effect may be mainly related to COX-2 inhibition by oroxylin A in HT-29 cells.
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Affiliation(s)
- Jun Ha
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Li Zhao
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Qing Zhao
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Jing Yao
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Bin-Bin Zhu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Na Lu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Xue Ke
- Department of Pharmacy, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China
| | - Hui-Ying Yang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
| | - Zhiyu Li
- Department of Medicinal Chemistry, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China
| | - Qi-Dong You
- Department of Medicinal Chemistry, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China
| | - Qing-Long Guo
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, P. R. China
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95
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Defillipo PP, Raposo AH, Fedoce AG, Ferreira AS, Polonini HC, Gattaz WF, Raposo NRB. Inhibition of cPLA2 and sPLA2 Activities in Primary Cultures of Rat Cortical Neurons by Centella asiatica Water Extract. Nat Prod Commun 2012. [DOI: 10.1177/1934578x1200700709] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Leaf extract of Centella asiatica has been used as an alternative medicine for memory improvement in the Indian Ayurvedic system of medicine for a long time. Although several studies have revealed its effect in ameliorating the cognitive impairment in rat models of Alzheimer's disease, the molecular mechanism of C. asiatica on neuroprotection still remains unexplained. In this study, we investigated the effects of C. asiatica water extract on activity of subtypes of phospholipase A2 (PLA2) in primary cultures of rat cortical neurons and quantified by HPLC a possible molecule responsible for the activity. The cPLA2 and sPLA2 activities were inhibited in vitro by asiaticoside present in the water extract of C. asiatica. This extract may be a candidate for the treatment of neurodegenerative processes because of its pharmacological activity in the brain and its low toxicity, as attested by its long popular use as a natural product.
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Affiliation(s)
- Patrícia P. Defillipo
- Laboratory of Neuroscience LIM 27, Department and Institute of Psychiatry, Faculty of Medicine, University of São Paulo (USP), São Paulo, Brazil
| | - André H. Raposo
- Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Faculty of Pharmacy, Federal University of Juiz de Fora (UFJF), Minas Gerais, Brazil
| | - Alessandra G. Fedoce
- Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Faculty of Pharmacy, Federal University of Juiz de Fora (UFJF), Minas Gerais, Brazil
| | - Aline S. Ferreira
- Laboratory of Neuroscience LIM 27, Department and Institute of Psychiatry, Faculty of Medicine, University of São Paulo (USP), São Paulo, Brazil
- Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Faculty of Pharmacy, Federal University of Juiz de Fora (UFJF), Minas Gerais, Brazil
| | - Hudson C. Polonini
- Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Faculty of Pharmacy, Federal University of Juiz de Fora (UFJF), Minas Gerais, Brazil
| | - Wagner F. Gattaz
- Laboratory of Neuroscience LIM 27, Department and Institute of Psychiatry, Faculty of Medicine, University of São Paulo (USP), São Paulo, Brazil
| | - Nádia R. B. Raposo
- Laboratory of Neuroscience LIM 27, Department and Institute of Psychiatry, Faculty of Medicine, University of São Paulo (USP), São Paulo, Brazil
- Núcleo de Pesquisa e Inovação em Ciências da Saúde (NUPICS), Faculty of Pharmacy, Federal University of Juiz de Fora (UFJF), Minas Gerais, Brazil
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96
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Chen SD, Yin JH, Hwang CS, Tang CM, Yang DI. Anti-apoptotic and anti-oxidative mechanisms of minocycline against sphingomyelinase/ceramide neurotoxicity: implication in Alzheimer's disease and cerebral ischemia. Free Radic Res 2012; 46:940-50. [PMID: 22583533 DOI: 10.3109/10715762.2012.674640] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sphingolipids represent a major class of lipids in which selected family members act as bioactive molecules that control diverse cellular processes, such as proliferation, differentiation, growth, senescence, migration and apoptosis. Emerging evidence reveals that sphingomyelinase/ceramide pathway plays a pivotal role in neurodegenerative diseases that involve mitochondrial dysfunction, oxidative stress and apoptosis. Minocycline, a semi-synthetic second-generation tetracycline derivative in clinical use for infection control, is also considered an effective protective agent in various neurodegenerative diseases in pre-clinical studies. Acting via multiple mechanisms, including anti-inflammatory, anti-oxidative and anti-apoptotic effects, minocycline is a desirable candidate for clinical trials in both acute brain injury as well as chronic neurodegenerative disorders. This review is focused on the anti-apoptotic and anti-oxidative mechanisms of minocycline against neurotoxicity induced by sphingomyelinase/ceramide in relation to neurodegeneration, particularly Alzheimer's disease and cerebral ischemia.
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Affiliation(s)
- Shang-Der Chen
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
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97
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Bate C, Williams A. Neurodegeneration induced by clustering of sialylated glycosylphosphatidylinositols of prion proteins. J Biol Chem 2012; 287:7935-44. [PMID: 22262833 DOI: 10.1074/jbc.m111.275743] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The transmissible spongiform encephalopathies, more commonly known as the prion diseases, are associated with the production and aggregation of disease-related isoforms of the prion protein (PrP(Sc)). The mechanisms by which PrP(Sc) accumulation causes neurodegeneration in these diseases are poorly understood. In cultured neurons, the addition of PrP(Sc) alters cell membranes, increasing cholesterol, activating cytoplasmic phospholipase A(2) (cPLA(2)), and triggering synapse damage. These effects of PrP(Sc) are dependent upon its glycosylphosphatidylinositol (GPI) anchor, suggesting that it is the increased density of GPIs that occurs following the aggregation of PrP(Sc) molecules that triggers neurodegeneration. This hypothesis was supported by observations that cross-linkage of the normal cellular prion protein (PrP(C)) also increased membrane cholesterol, activated cPLA(2), and triggered synapse damage. These effects were not seen after cross-linkage of Thy-1, another GPI-anchored protein, and were dependent on the GPI anchor attached to PrP(C) containing two acyl chains and sialic acid. We propose that the aggregation of PrP(Sc), or the cross-linkage of PrP(C), causes the clustering of sialic acid-containing GPI anchors at high densities, resulting in altered membrane composition, the pathological activation of cPLA(2), and synapse damage.
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Affiliation(s)
- Clive Bate
- Department of Pathology and Infectious Diseases, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, United Kingdom.
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98
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The Roles of Neutral Sphingomyelinases in Neurological Pathologies. Neurochem Res 2012; 37:1137-49. [DOI: 10.1007/s11064-011-0692-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 11/25/2011] [Accepted: 12/29/2011] [Indexed: 12/14/2022]
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99
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Dontigny E, Patenaude C, Cyr M, Massicotte G. Sphingomyelinase selectively reduces M1 muscarinic receptors in rat hippocampal membranes. Hippocampus 2012; 22:1589-96. [PMID: 22228652 DOI: 10.1002/hipo.21001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2011] [Indexed: 01/20/2023]
Abstract
Although there is evidence that nicotinic acetylcholine (Ach) receptors are influenced by ceramides, we do not currently know whether or not these sphingolipids can also regulate the muscarinic subtypes of Ach receptors. Using the whole-cell patch technique, we demonstrated that the effectiveness of the muscarinic receptor agonist pilocarpine, in enhancing spontaneous inhibitory postsynaptic currents in CA1 pyramidal cells, was completely abolished in hippocampal slices pre-exposed to the ceramide-generating enzyme sphingomyelinase (SMase). Western blot experiments, performed with biotinylated hippocampal membranes, showed that this electrophysiological defect possibly relies on the loss of M1 muscarinic Ach receptors at the cell surface. However, the effect appears to be relatively specific as the cell-surface expression of M4 muscarinic receptors was not found to be impacted by SMase treatment. Interestingly, we observed that G protein-coupled receptor kinases 2 and β-arrestin1/2 interactions with M1-immunoprecipitated proteins were substantially augmented in SMase-treated slices and that the reduction of cell-surface M1 muscarinic receptor expression generated was completely suppressed by the muscarinic antagonist atropine. Collectively, our data suggest that selective internalization of M1 muscarinic receptors can be accentuated in neurons subjected to high ceramide levels. The potential physiopathological implications of this finding are presented.
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Affiliation(s)
- Eve Dontigny
- Groupe de recherche en Neuroscience, Université du Québec à Trois-Rivières, Trois-Rivières, Québec, Canada
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100
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Desbène C, Malaplate-Armand C, Youssef I, Garcia P, Stenger C, Sauvée M, Fischer N, Rimet D, Koziel V, Escanyé MC, Oster T, Kriem B, Yen FT, Pillot T, Olivier JL. Critical role of cPLA2 in Aβ oligomer-induced neurodegeneration and memory deficit. Neurobiol Aging 2011; 33:1123.e17-29. [PMID: 22188721 DOI: 10.1016/j.neurobiolaging.2011.11.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 11/03/2011] [Accepted: 11/04/2011] [Indexed: 12/23/2022]
Abstract
Soluble beta-amyloid (Aβ) oligomers are considered to putatively play a critical role in the early synapse loss and cognitive impairment observed in Alzheimer's disease. We previously demonstrated that Aβ oligomers activate cytosolic phospholipase A(2) (cPLA(2)), which specifically releases arachidonic acid from membrane phospholipids. We here observed that cPLA(2) gene inactivation prevented the alterations of cognitive abilities and the reduction of hippocampal synaptic markers levels noticed upon a single intracerebroventricular injection of Aβ oligomers in wild type mice. We further demonstrated that the Aβ oligomer-induced sphingomyelinase activation was suppressed and that phosphorylation of Akt/protein kinase B (PKB) was preserved in neuronal cells isolated from cPLA(2)(-/-) mice. Interestingly, expression of the Aβ precursor protein (APP) was reduced in hippocampus homogenates and neuronal cells from cPLA(2)(-/-) mice, but the relationship with the resistance of these mice to the Aβ oligomer toxicity requires further investigation. These results therefore show that cPLA(2) plays a key role in the Aβ oligomer-associated neurodegeneration, and as such represents a potential therapeutic target for the treatment of Alzheimer's disease.
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Affiliation(s)
- Cédric Desbène
- Lipidomix (EA 4422), INPL-ENSAIA, Université de Lorraine, Vandœuvre-lès-Nancy, France
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