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Grenon MB, Papavergi MT, Bathini P, Sadowski M, Lemere CA. Temporal Characterization of the Amyloidogenic APPswe/PS1dE9;hAPOE4 Mouse Model of Alzheimer's Disease. Int J Mol Sci 2024; 25:5754. [PMID: 38891941 PMCID: PMC11172317 DOI: 10.3390/ijms25115754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Revised: 05/16/2024] [Accepted: 05/21/2024] [Indexed: 06/21/2024] Open
Abstract
Alzheimer's disease (AD) is a devastating disorder with a global prevalence estimated at 55 million people. In clinical studies administering certain anti-beta-amyloid (Aβ) antibodies, amyloid-related imaging abnormalities (ARIAs) have emerged as major adverse events. The frequency of these events is higher among apolipoprotein ε4 allele carriers (APOE4) compared to non-carriers. To reflect patients most at risk for vascular complications of anti-Aβ immunotherapy, we selected an APPswe/PS1dE9 transgenic mouse model bearing the human APOE4 gene (APPPS1:E4) and compared it with the same APP/PS1 mouse model bearing the human APOE3 gene (APOE ε3 allele; APPPS1:E3). Using histological and biochemical analyses, we characterized mice at three ages: 8, 12, and 16 months. Female and male mice were assayed for general cerebral fibrillar and pyroglutamate (pGlu-3) Aβ deposition, cerebral amyloid angiopathy (CAA), microhemorrhages, apoE and cholesterol composition, astrocytes, microglia, inflammation, lysosomal dysfunction, and neuritic dystrophy. Amyloidosis, lipid deposition, and astrogliosis increased with age in APPPS1:E4 mice, while inflammation did not reveal significant changes with age. In general, APOE4 carriers showed elevated Aβ, apoE, reactive astrocytes, pro-inflammatory cytokines, microglial response, and neuritic dystrophy compared to APOE3 carriers at different ages. These results highlight the potential of the APPPS1:E4 mouse model as a valuable tool in investigating the vascular side effects associated with anti-amyloid immunotherapy.
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Affiliation(s)
- Martine B. Grenon
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (M.B.G.); (M.-T.P.); (P.B.)
- Section Neuropsychology & Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Maria-Tzousi Papavergi
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (M.B.G.); (M.-T.P.); (P.B.)
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience (MHeNs), Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Praveen Bathini
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (M.B.G.); (M.-T.P.); (P.B.)
| | - Martin Sadowski
- Departments of Neurology, Psychiatry, and Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA;
| | - Cynthia A. Lemere
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (M.B.G.); (M.-T.P.); (P.B.)
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Dunk MM, Rapp SR, Hayden KM, Espeland MA, Casanova R, Manson JE, Shadyab AH, Wild R, Driscoll I. Plasma oxysterols are associated with serum lipids and dementia risk in older women. Alzheimers Dement 2024; 20:3696-3704. [PMID: 38574442 PMCID: PMC11095475 DOI: 10.1002/alz.13811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 12/21/2023] [Accepted: 12/28/2023] [Indexed: 04/06/2024]
Abstract
INTRODUCTION Apolipoprotein E4 (APOE4) carriers' tendency toward hypercholesterolemia may contribute to Alzheimer's disease (AD) risk through oxysterols, which traverse the blood-brain barrier. METHODS Relationships between baseline plasma oxysterols, APOE status, serum lipids, and cognitive impairment risk were examined in 328 postmenopausal women from the Women's Health Initiative Memory Study. Women were followed for 25 years or until incident dementia or cognitive impairment. RESULTS Levels of 24(S)-hydroxycholesterol (24-OHC), 27-hydroxycholesterol (27-OHC), and 24-OHC/27-OHC ratio did not differ by APOE status (p's > 0.05). Higher 24-OHC and 27-OHC were associated with higher total, low density lipoprotein (LDL), non-high density lipoprotein (HDL), remnant, LDL/HDL, and total/HDL cholesterol and triglycerides (p's < 0.05). Higher 24-OHC/27-OHC was associated with greater dementia risk (hazard ratio = 1.51, 95% confidence interval:1.02-2.22), which interaction analyses revealed as significant for APOE3 and APOE4+, but not APOE2+ carriers. DISCUSSION Less favorable lipid profiles were associated with higher oxysterol levels. A higher ratio of 24-OHC/27-OHC may contribute to dementia risk in APOE3 and APOE4+ carriers.
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Affiliation(s)
- Michelle M. Dunk
- Department of PsychologyUniversity of Wisconsin – MilwaukeeMilwaukeeWisconsinUSA
- Aging Research CenterDepartment of Neurobiology, Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Stephen R. Rapp
- Department of Social Sciences and Health PolicyDivision of Public Health SciencesWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
- Department of Psychiatry and Behavioral MedicineWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Kathleen M. Hayden
- Department of Social Sciences and Health PolicyDivision of Public Health SciencesWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Mark A. Espeland
- Department of Social Sciences and Health PolicyDivision of Public Health SciencesWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
- Department of Biostatistics and Data ScienceWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
- Sticht Center for Healthy Aging and Alzheimer's PreventionWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - Ramon Casanova
- Department of Biostatistics and Data ScienceWake Forest University School of MedicineWinston‐SalemNorth CarolinaUSA
| | - JoAnn E. Manson
- Department of MedicineBrigham and Women's Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of EpidemiologyHarvard T.H. Chan School of Public HealthBostonMassachusettsUSA
| | - Aladdin H. Shadyab
- Herbert Wertheim School of Public Health and Human Longevity ScienceUniversity of California San DiegoLa JollaCaliforniaUSA
- Division of Geriatrics, Gerontology, and Palliative Care, Department of MedicineUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Robert Wild
- Departments of Obstetrics and Gynecology, Biostatistics and EpidemiologyOklahoma University Health Sciences CenterOklahoma CityOklahomaUSA
| | - Ira Driscoll
- Department of PsychologyUniversity of Wisconsin – MilwaukeeMilwaukeeWisconsinUSA
- Wisconsin Alzheimer's Disease Research CenterUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
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Guarnieri L, Bosco F, Leo A, Citraro R, Palma E, De Sarro G, Mollace V. Impact of micronutrients and nutraceuticals on cognitive function and performance in Alzheimer's disease. Ageing Res Rev 2024; 95:102210. [PMID: 38296163 DOI: 10.1016/j.arr.2024.102210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 01/10/2024] [Accepted: 01/25/2024] [Indexed: 02/13/2024]
Abstract
Alzheimer's disease (AD) is a major global health problem today and is the most common form of dementia. AD is characterized by the formation of β-amyloid (Aβ) plaques and neurofibrillary clusters, leading to decreased brain acetylcholine levels in the brain. Another mechanism underlying the pathogenesis of AD is the abnormal phosphorylation of tau protein that accumulates at the level of neurofibrillary aggregates, and the areas most affected by this pathological process are usually the cholinergic neurons in cortical, subcortical, and hippocampal areas. These effects result in decreased cognitive function, brain atrophy, and neuronal death. Malnutrition and weight loss are the most frequent manifestations of AD, and these are also associated with greater cognitive decline. Several studies have confirmed that a balanced low-calorie diet and proper nutritional intake may be considered important factors in counteracting or slowing the progression of AD, whereas a high-fat or hypercholesterolemic diet predisposes to an increased risk of developing AD. Especially, fruits, vegetables, antioxidants, vitamins, polyunsaturated fatty acids, and micronutrients supplementation exert positive effects on aging-related changes in the brain due to their antioxidant, anti-inflammatory, and radical scavenging properties. The purpose of this review is to summarize some possible nutritional factors that may contribute to the progression or prevention of AD, understand the role that nutrition plays in the formation of Aβ plaques typical of this neurodegenerative disease, to identify some potential therapeutic strategies that may involve some natural compounds, in delaying the progression of the disease.
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Affiliation(s)
- Lorenza Guarnieri
- Section of Pharmacology, Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy
| | - Francesca Bosco
- Section of Pharmacology, Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy.
| | - Antonio Leo
- Section of Pharmacology, Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy; Research Center FAS@UMG, Department of Health Science, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy
| | - Rita Citraro
- Section of Pharmacology, Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy; Research Center FAS@UMG, Department of Health Science, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy
| | - Ernesto Palma
- Department of Health Sciences, Institute of Research for Food Safety and Health (IRC-FSH), University Magna Graecia of Catanzaro, 88100 Catanzaro, Italy
| | - Giovambattista De Sarro
- Section of Pharmacology, Science of Health Department, School of Medicine, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy; Research Center FAS@UMG, Department of Health Science, University "Magna Graecia" of Catanzaro, 88100 Catanzaro, Italy
| | - Vincenzo Mollace
- Department of Health Sciences, Institute of Research for Food Safety and Health (IRC-FSH), University Magna Graecia of Catanzaro, 88100 Catanzaro, Italy
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Kawade N, Yamanaka K. Novel insights into brain lipid metabolism in Alzheimer's disease: Oligodendrocytes and white matter abnormalities. FEBS Open Bio 2024; 14:194-216. [PMID: 37330425 PMCID: PMC10839347 DOI: 10.1002/2211-5463.13661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/07/2023] [Accepted: 06/14/2023] [Indexed: 06/19/2023] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia. A genome-wide association study has shown that several AD risk genes are involved in lipid metabolism. Additionally, epidemiological studies have indicated that the levels of several lipid species are altered in the AD brain. Therefore, lipid metabolism is likely changed in the AD brain, and these alterations might be associated with an exacerbation of AD pathology. Oligodendrocytes are glial cells that produce the myelin sheath, which is a lipid-rich insulator. Dysfunctions of the myelin sheath have been linked to white matter abnormalities observed in the AD brain. Here, we review the lipid composition and metabolism in the brain and myelin and the association between lipidic alterations and AD pathology. We also present the abnormalities in oligodendrocyte lineage cells and white matter observed in AD. Additionally, we discuss metabolic disorders, including obesity, as AD risk factors and the effects of obesity and dietary intake of lipids on the brain.
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Affiliation(s)
- Noe Kawade
- Department of Neuroscience and Pathobiology, Research Institute of Environmental MedicineNagoya UniversityJapan
- Department of Neuroscience and Pathobiology, Nagoya University Graduate School of MedicineNagoya UniversityJapan
| | - Koji Yamanaka
- Department of Neuroscience and Pathobiology, Research Institute of Environmental MedicineNagoya UniversityJapan
- Department of Neuroscience and Pathobiology, Nagoya University Graduate School of MedicineNagoya UniversityJapan
- Institute for Glyco‐core Research (iGCORE)Nagoya UniversityJapan
- Center for One Medicine Innovative Translational Research (COMIT)Nagoya UniversityJapan
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Olkkonen VM, Gylling H. Oxy- and Phytosterols as Biomarkers: Current Status and Future Perspectives. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1440:353-375. [PMID: 38036889 DOI: 10.1007/978-3-031-43883-7_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Oxysterols and phytosterols are sterol compounds present at markedly low levels in tissues and serum of healthy individuals. A wealth of evidence suggests that they could be employed as biomarkers for human diseases or for cholesterol absorption.An increasing number of reports suggest circulating or tissue oxysterols as putative biomarkers for cardiovascular and neurodegenerative diseases or cancers. Thus far most of the studies have been carried out on small study populations. To achieve routine biomarker use, large prospective cohort studies are absolutely required. This, again, would necessitate thorough standardization of the oxysterol analytical methodology across the different laboratories, which now employ different technologies resulting in inconsistencies in the measured oxysterol levels. Routine use of oxysterol biomarkers would also necessitate the development of a new targeted analytical methodology suitable for high-throughput platforms.The most important use of phytosterols as biomarkers involves their use as markers for cholesterol absorption. For this to be achieved, (1) their quantitative analyses should be available in routine lipid laboratories, (2) it should be generally acknowledgment that the profile of cholesterol metabolism can reveal the risk of the development of atherosclerotic cardiovascular diseases (ASCVD), and (3) screening of the profile of cholesterol metabolism should be included in the ASCVD risk surveys. This should be done e.g. in families with a history of early onset or frequent ASCVD and in young adults aged 18-20 years, to exclude the presence of high cholesterol absorption. Individuals in high cholesterol absorption families need preventive measures from young adulthood to inhibit the possible development and progression of atherosclerosis.
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Affiliation(s)
- Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Biomedicum 2U, Helsinki, Finland.
- Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Helena Gylling
- Heart and Lung Center, Cardiology, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
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24-Hydroxycholesterol Induces Tau Proteasome-Dependent Degradation via the SIRT1/PGC1α/Nrf2 Pathway: A Potential Mechanism to Counteract Alzheimer’s Disease. Antioxidants (Basel) 2023; 12:antiox12030631. [PMID: 36978879 PMCID: PMC10044740 DOI: 10.3390/antiox12030631] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 02/17/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023] Open
Abstract
Considerable evidence indicates that cholesterol oxidation products, named oxysterols, play a key role in several events involved in Alzheimer’s disease (AD) pathogenesis. Although the majority of oxysterols causes neuron dysfunction and degeneration, 24-hydroxycholesterol (24-OHC) has recently been thought to be neuroprotective also. The present study aimed at supporting this concept by exploring, in SK-N-BE neuroblastoma cells, whether 24-OHC affected the neuroprotective SIRT1/PGC1α/Nrf2 axis. We demonstrated that 24-OHC, through the up-regulation of the deacetylase SIRT1, was able to increase both PGC1α and Nrf2 expression and protein levels, as well as Nrf2 nuclear translocation. By acting on this neuroprotective pathway, 24-OHC favors tau protein clearance by triggering tau ubiquitination and subsequently its degradation through the ubiquitin–proteasome system. We also observed a modulation of SIRT1, PGC1α, and Nrf2 expression and synthesis in the brain of AD patients with the progression of the disease, suggesting their potential role in neuroprotection. These findings suggest that 24-OHC contributes to tau degradation through the up-regulation of the SIRT1/PGC1α/Nrf2 axis. Overall, the evidence points out the importance of avoiding 24-OHC loss, which can occur in the AD brain, and of limiting SIRT1, PGC1α, and Nrf2 deregulation in order to prevent the neurotoxic accumulation of hyperphosphorylated tau and counteract neurodegeneration.
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Yin F. Lipid metabolism and Alzheimer's disease: clinical evidence, mechanistic link and therapeutic promise. FEBS J 2023; 290:1420-1453. [PMID: 34997690 PMCID: PMC9259766 DOI: 10.1111/febs.16344] [Citation(s) in RCA: 82] [Impact Index Per Article: 82.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 12/14/2021] [Accepted: 01/05/2022] [Indexed: 02/06/2023]
Abstract
Alzheimer's disease (AD) is an age-associated neurodegenerative disorder with multifactorial etiology, intersecting genetic and environmental risk factors, and a lack of disease-modifying therapeutics. While the abnormal accumulation of lipids was described in the very first report of AD neuropathology, it was not until recent decades that lipid dyshomeostasis became a focus of AD research. Clinically, lipidomic and metabolomic studies have consistently shown alterations in the levels of various lipid classes emerging in early stages of AD brains. Mechanistically, decades of discovery research have revealed multifaceted interactions between lipid metabolism and key AD pathogenic mechanisms including amyloidogenesis, bioenergetic deficit, oxidative stress, neuroinflammation, and myelin degeneration. In the present review, converging evidence defining lipid dyshomeostasis in AD is summarized, followed by discussions on mechanisms by which lipid metabolism contributes to pathogenesis and modifies disease risk. Furthermore, lipid-targeting therapeutic strategies, and the modification of their efficacy by disease stage, ApoE status, and metabolic and vascular profiles, are reviewed.
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Affiliation(s)
- Fei Yin
- Center for Innovation in Brain Science, University of Arizona Health Sciences, Tucson, AZ, USA.,Department of Pharmacology, College of Medicine Tucson, University of Arizona, Tucson, AZ, USA.,Graduate Interdisciplinary Program in Neuroscience, University of Arizona, Tucson, AZ, USA
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8
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Stefaniak O, Dobrzyńska M, Drzymała-Czyż S, Przysławski J. Diet in the Prevention of Alzheimer's Disease: Current Knowledge and Future Research Requirements. Nutrients 2022; 14:4564. [PMID: 36364826 PMCID: PMC9656789 DOI: 10.3390/nu14214564] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/23/2022] [Accepted: 10/25/2022] [Indexed: 08/13/2023] Open
Abstract
Alzheimer's disease is a progressive brain disease that is becoming a major health problem in today's world due to the aging population. Despite it being widely known that diet has a significant impact on the prevention and progression of Alzheimer's disease, the literature data are still scarce and controversial. The application of the principles of rational nutrition for the elderly is suggested for Alzheimer's disease. The diet should be rich in neuroprotective nutrients, i.e., antioxidants, B vitamins, and polyunsaturated fatty acids. Some studies suggest that diets such as the Mediterranean diet, the DASH (Dietary Approaches to Stop Hypertension) diet, and the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet have a beneficial effect on the risk of developing Alzheimer's disease.
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Affiliation(s)
| | - Małgorzata Dobrzyńska
- Department of Bromatology, Poznan University of Medical Science, Rokietnicka 3 Street, 60-806 Poznan, Poland
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Wu M, Zhai Y, Liang X, Chen W, Lin R, Ma L, Huang Y, Zhao D, Liang Y, Zhao W, Fang J, Fang S, Chen Y, Wang Q, Li W. Connecting the Dots Between Hypercholesterolemia and Alzheimer’s Disease: A Potential Mechanism Based on 27-Hydroxycholesterol. Front Neurosci 2022; 16:842814. [PMID: 35464321 PMCID: PMC9021879 DOI: 10.3389/fnins.2022.842814] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 03/01/2022] [Indexed: 12/13/2022] Open
Abstract
Alzheimer’s disease (AD), the most common cause of dementia, is a complex and multifactorial disease involving genetic and environmental factors, with hypercholesterolemia considered as one of the risk factors. Numerous epidemiological studies have reported a positive association between AD and serum cholesterol levels, and experimental studies also provide evidence that elevated cholesterol levels accelerate AD pathology. However, the underlying mechanism of hypercholesterolemia accelerating AD pathogenesis is not clear. Here, we review the metabolism of cholesterol in the brain and focus on the role of oxysterols, aiming to reveal the link between hypercholesterolemia and AD. 27-hydroxycholesterol (27-OHC) is the major peripheral oxysterol that flows into the brain, and it affects β-amyloid (Aβ) production and elimination as well as influencing other pathogenic mechanisms of AD. Although the potential link between hypercholesterolemia and AD is well established, cholesterol-lowering drugs show mixed results in improving cognitive function. Nevertheless, drugs that target cholesterol exocytosis and conversion show benefits in improving AD pathology. Herbs and natural compounds with cholesterol-lowering properties also have a potential role in ameliorating cognition. Collectively, hypercholesterolemia is a causative risk factor for AD, and 27-OHC is likely a potential mechanism for hypercholesterolemia to promote AD pathology. Drugs that regulate cholesterol metabolism are probably beneficial for AD, but more research is needed to unravel the mechanisms involved in 27-OHC, which may lead to new therapeutic strategies for AD.
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Affiliation(s)
- Mingan Wu
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yingying Zhai
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiaoyi Liang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Weichun Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Ruiyi Lin
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Linlin Ma
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yi Huang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Di Zhao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yong Liang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Wei Zhao
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiansong Fang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shuhuan Fang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yunbo Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qi Wang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
- *Correspondence: Qi Wang,
| | - Weirong Li
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
- Weirong Li,
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Feringa FM, van der Kant R. Cholesterol and Alzheimer's Disease; From Risk Genes to Pathological Effects. Front Aging Neurosci 2021; 13:690372. [PMID: 34248607 PMCID: PMC8264368 DOI: 10.3389/fnagi.2021.690372] [Citation(s) in RCA: 105] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/28/2021] [Indexed: 12/22/2022] Open
Abstract
While the central nervous system compromises 2% of our body weight, it harbors up to 25% of the body's cholesterol. Cholesterol levels in the brain are tightly regulated for physiological brain function, but mounting evidence indicates that excessive cholesterol accumulates in Alzheimer's disease (AD), where it may drive AD-associated pathological changes. This seems especially relevant for late-onset AD, as several of the major genetic risk factors are functionally associated with cholesterol metabolism. In this review we discuss the different systems that maintain brain cholesterol metabolism in the healthy brain, and how dysregulation of these processes can lead, or contribute to, Alzheimer's disease. We will also discuss how AD-risk genes might impact cholesterol metabolism and downstream AD pathology. Finally, we will address the major outstanding questions in the field and how recent technical advances in CRISPR/Cas9-gene editing and induced pluripotent stem cell (iPSC)-technology can aid to study these problems.
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Affiliation(s)
- Femke M. Feringa
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam University Medical Center, Amsterdam, Netherlands
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, Netherlands
| | - Rik van der Kant
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), VU University Amsterdam, Amsterdam, Netherlands
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, Netherlands
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Nanjundaiah S, Chidambaram H, Chandrashekar M, Chinnathambi S. Role of Microglia in Regulating Cholesterol and Tau Pathology in Alzheimer's Disease. Cell Mol Neurobiol 2021; 41:651-668. [PMID: 32468440 DOI: 10.1007/s10571-020-00883-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 05/19/2020] [Indexed: 01/21/2023]
Abstract
Cholesterol, a principal constituent of the cell membrane, plays a crucial role in the brain by regulating the synaptic transmission, neuronal signaling, as well as neurodegenerative diseases. Defects in the cholesterol trafficking are associated with enhanced generation of hyperphosphorylated Tau and Amyloid-β protein. Tau, a major microtubule-associated protein in the brain, is the key regulator of the mature neuron. Abnormally hyperphosphorylated Tau hampers the major functions related to microtubule assembly by promoting neurofibrillary tangles of paired helical filaments, twisted ribbons, and straight filaments. The observed pathological changes due to impaired cholesterol and Tau protein accumulation cause Alzheimer's disease. Thus, in order to regulate the pathogenesis of Alzheimer's disease, regulation of cholesterol metabolism, as well as Tau phosphorylation, is essential. The current review provides an overview of (1) cholesterol synthesis in the brain, neurons, astrocytes, and microglia; (2) the mechanism involved in modulating cholesterol concentration between the astrocytes and brain; (3) major mechanisms involved in the hyperphosphorylation of Tau and amyloid-β protein; and (4) microglial involvement in its regulation. Thus, the answering key questions will provide an in-depth information on microglia involvement in managing the pathogenesis of cholesterol-modulated hyperphosphorylated Tau protein.
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Affiliation(s)
- Shwetha Nanjundaiah
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411008, India
| | - Hariharakrishnan Chidambaram
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi, 110025, India
| | - Madhura Chandrashekar
- School of Biomedical Engineering and Sciences, MIT University, Loni Kalbhor, Pune, 412201, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, Pune, 411008, India.
- Academy of Scientific and Innovative Research (AcSIR), New Delhi, 110025, India.
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Bok E, Leem E, Lee BR, Lee JM, Yoo CJ, Lee EM, Kim J. Role of the Lipid Membrane and Membrane Proteins in Tau Pathology. Front Cell Dev Biol 2021; 9:653815. [PMID: 33996814 PMCID: PMC8119898 DOI: 10.3389/fcell.2021.653815] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/09/2021] [Indexed: 12/12/2022] Open
Abstract
Abnormal accumulation of misfolded tau aggregates is a pathological hallmark of various tauopathies including Alzheimer’s disease (AD). Although tau is a cytosolic microtubule-associated protein enriched in neurons, it is also found in extracellular milieu, such as interstitial fluid, cerebrospinal fluid, and blood. Accumulating evidence showed that pathological tau spreads along anatomically connected areas in the brain through intercellular transmission and templated misfolding, thereby inducing neurodegeneration and cognitive dysfunction. In line with this, the spatiotemporal spreading of tau pathology is closely correlated with cognitive decline in AD patients. Although the secretion and uptake of tau involve multiple different pathways depending on tau species and cell types, a growing body of evidence suggested that tau is largely secreted in a vesicle-free forms. In this regard, the interaction of vesicle-free tau with membrane is gaining growing attention due to its importance for both of tau secretion and uptake as well as aggregation. Here, we review the recent literature on the mechanisms of the tau-membrane interaction and highlights the roles of lipids and proteins at the membrane in the tau-membrane interaction as well as tau aggregation.
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Affiliation(s)
- Eugene Bok
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Eunju Leem
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Bo-Ram Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Ji Min Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea.,School of Life Sciences, Kyungpook National University, Daegu, South Korea
| | - Chang Jae Yoo
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Eun Mi Lee
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Jaekwang Kim
- Dementia Research Group, Korea Brain Research Institute, Daegu, South Korea
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13
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Oxysterols as a biomarker in diseases. Clin Chim Acta 2019; 491:103-113. [PMID: 30685361 DOI: 10.1016/j.cca.2019.01.022] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/20/2019] [Accepted: 01/23/2019] [Indexed: 12/24/2022]
Abstract
Cholesterol is one of the most important chemical substances as a structural element in human cells, and it is very susceptible to oxidation reactions that form oxysterol. Oxysterols exhibit almost the exact structure as cholesterol and a cholesterol precursor (7-dehydrocholesterol) with an additional hydroxyl, epoxy or ketone moiety. The oxidation reaction is performed via an enzymatic or non-enzymatic mechanism. The wide array of enzymatic oxysterols encountered in the human body varies in origin and function. Oxysterols establish a concentration equilibrium in human body fluids. Disease may alter the equilibrium, and oxysterols may be used as a diagnostic tool. The current review presents the possibility of using non-enzymatic oxysterols and disturbances in enzymatic oxysterol equilibrium in the human body as a potential biomarker for diagnosing and/or monitoring of the progression of various diseases.
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Li G, Mayer CL, Morelli D, Millard SP, Raskind WH, Petrie EC, Cherrier M, Fagan AM, Raskind MA, Peskind ER. Effect of simvastatin on CSF Alzheimer disease biomarkers in cognitively normal adults. Neurology 2017; 89:1251-1255. [PMID: 28821686 DOI: 10.1212/wnl.0000000000004392] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 06/29/2017] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To examine potential disease-modifying effects of statin drugs, we conducted a 12-month randomized, placebo-controlled clinical trial of simvastatin in cognitively normal adults using change in CSF Alzheimer disease biomarkers as primary outcome measure. METHODS Participants were 45-64 years old and statin-naive with normal cognition and normal or mildly elevated cholesterol. Forty-six participants completed the 1-year study per protocol (25 in the simvastatin and 21 in the placebo group). Simvastatin was titrated to 40 mg/d. CSF Aβ42, total tau, and p-tau181 were measured at baseline and after 12 months of treatment using the INNO-BIA AlzBio3 assay. We used analysis of covariance to assess differences in biomarker change from baseline between treatment groups, adjusting for age, sex, and APOE ε4 status. RESULTS Changes from baseline did not differ significantly between treatment groups for any CSF biomarker, with p values of 0.53, 0.36, and 0.25 for CSF Aβ42, total tau, and p-tau181, respectively. There was no significant modifying effect of sex, APOE ε4, or baseline high-density lipoprotein or triglycerides on treatment group for any of the biomarkers (all p > 0.18). However, a significant interaction between treatment group and baseline low-density lipoprotein (LDL) was observed for p-tau181 (p = 0.003), where greater decreases from baseline in CSF p-tau181 concentrations were associated with higher baseline LDL level for the simvastatin group. CONCLUSIONS Simvastatin-related reductions in CSF p-tau181 concentrations may be modulated by LDL cholesterol. The potential disease-modifying effects of simvastatin on CSF phospho-tau should be further investigated in persons with hypercholesterolemia.
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Affiliation(s)
- Ge Li
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO.
| | - Cynthia L Mayer
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Daniel Morelli
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Steven P Millard
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Wendy H Raskind
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Eric C Petrie
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Monique Cherrier
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Anne M Fagan
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Murray A Raskind
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
| | - Elaine R Peskind
- From the Geriatric Research, Education, and Clinical Center (G.L., W.H.R.) and Northwest Network (VISN-20) Mental Illness, Research, Education, and Clinical Center (G.L., C.L.M., D.M., S.P.M., E.C.P., M.A.R., E.R.P.), Veterans Affairs Puget Sound Health Care System; Departments of Psychiatry and Behavioral Sciences (G.L., E.C.P., M.C., M.A.R., E.R.P.) and Medicine (W.H.R.), University of Washington, Seattle; and Department of Neurology (A.M.F.), Washington University in St. Louis, MO
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Buccarello L, Grignaschi G, Di Giancamillo A, Domeneghini C, Melcangi RC, Borsello T. Neuroprotective effects of low fat-protein diet in the P301L mouse model of tauopathy. Neuroscience 2017; 354:208-220. [PMID: 28456717 DOI: 10.1016/j.neuroscience.2017.04.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/19/2017] [Accepted: 04/19/2017] [Indexed: 12/13/2022]
Abstract
Tauopathies are a class of neurodegenerative diseases associated with the pathological aggregation of tau protein in the human brain. Although numerous studies in mouse models of Alzheimer disease (AD) have shown a correlation among diet, beta-amyloid and AD onset, little is known about the impact of diet on Tau. We investigated whether a low fat-protein diet (LFPD) may improve lifespan, cognitive and locomotor activity in P301L-tg mouse model of tauopathy. Our data indicate that LFPD has a beneficial effect on these parameters. Tg mice fed with standard diet shown a decrease in body weight, food intake and survival rate if compared to wild type animals. In contrast, LFPD counteracted weight loss, increased mortality and ameliorated cognitive and locomotor performances in tg mice. LFPD also reduced the abnormal accumulation of agglomerates of P-Tau (pathological features of tauopathies) and the expression of apoptotic markers (i.e., TUNEL immunopositive neurons) in the prefrontal cerebral cortex and hippocampus of P301L-tg mice. Interestingly, some of these effects are sex-dependent. For instance, tg females, but not males, fed with LFPD had a significant increase of body weight and a reduction of P-Tau agglomerates compared to tg fed with standard diet. These changes correlated with a more pronounced improvement of cognition and locomotor activity in females than in male tg fed with LFPD. Altogether, these results suggest a sex dependent neuroprotective effect of LFPD in P301L-tg mice, suggesting that lifestyle intervention strategies may be clinically relevant for delaying the onset of cognitive impairment and dementia, especially in females.
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Affiliation(s)
- Lucia Buccarello
- Department of Neuroscience, IRCCS-Mario Negri Institute for Pharmacological Research, Milan, Italy; Department of Health, Animal Science and Food Safety, Università degli Studi di Milano, Italy
| | - Giuliano Grignaschi
- Department of Animal Welfare, IRCCS-Mario Negri Institute for Pharmacological Research, Milan, Italy
| | - Alessia Di Giancamillo
- Department of Health, Animal Science and Food Safety, Università degli Studi di Milano, Italy
| | - Cinzia Domeneghini
- Department of Health, Animal Science and Food Safety, Università degli Studi di Milano, Italy
| | - Roberto Cosimo Melcangi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy
| | - Tiziana Borsello
- Department of Neuroscience, IRCCS-Mario Negri Institute for Pharmacological Research, Milan, Italy; Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy.
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Changes in brain oxysterols at different stages of Alzheimer's disease: Their involvement in neuroinflammation. Redox Biol 2016; 10:24-33. [PMID: 27687218 PMCID: PMC5040635 DOI: 10.1016/j.redox.2016.09.001] [Citation(s) in RCA: 182] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/07/2016] [Accepted: 09/09/2016] [Indexed: 12/29/2022] Open
Abstract
Alzheimer's disease (AD) is a gradually debilitating disease that leads to dementia. The molecular mechanisms underlying AD are still not clear, and at present no reliable biomarkers are available for the early diagnosis. In the last several years, together with oxidative stress and neuroinflammation, altered cholesterol metabolism in the brain has become increasingly implicated in AD progression. A significant body of evidence indicates that oxidized cholesterol, in the form of oxysterols, is one of the main triggers of AD. The oxysterols potentially most closely involved in the pathogenesis of AD are 24-hydroxycholesterol and 27-hydroxycholesterol, respectively deriving from cholesterol oxidation by the enzymes CYP46A1 and CYP27A1. However, the possible involvement of oxysterols resulting from cholesterol autooxidation, including 7-ketocholesterol and 7β-hydroxycholesterol, is now emerging. In a systematic analysis of oxysterols in post-mortem human AD brains, classified by the Braak staging system of neurofibrillary pathology, alongside the two oxysterols of enzymatic origin, a variety of oxysterols deriving from cholesterol autoxidation were identified; these included 7-ketocholesterol, 7α-hydroxycholesterol, 4β-hydroxycholesterol, 5α,6α-epoxycholesterol, and 5β,6β-epoxycholesterol. Their levels were quantified and compared across the disease stages. Some inflammatory mediators, and the proteolytic enzyme matrix metalloprotease-9, were also found to be enhanced in the brains, depending on disease progression. This highlights the pathogenic association between the trends of inflammatory molecules and oxysterol levels during the evolution of AD. Conversely, sirtuin 1, an enzyme that regulates several pathways involved in the anti-inflammatory response, was reduced markedly with the progression of AD, supporting the hypothesis that the loss of sirtuin 1 might play a key role in AD. Taken together, these results strongly support the association between changes in oxysterol levels and AD progression.
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17
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Belkouch M, Hachem M, Elgot A, Lo Van A, Picq M, Guichardant M, Lagarde M, Bernoud-Hubac N. The pleiotropic effects of omega-3 docosahexaenoic acid on the hallmarks of Alzheimer's disease. J Nutr Biochem 2016; 38:1-11. [PMID: 27825512 DOI: 10.1016/j.jnutbio.2016.03.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 12/14/2015] [Accepted: 03/03/2016] [Indexed: 12/17/2022]
Abstract
Among omega-3 polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (DHA, 22:6n-3) is important for adequate brain development and cognition. DHA is highly concentrated in the brain and plays an essential role in brain functioning. DHA, one of the major constituents in fish fats, readily crosses the blood-brain barrier from blood to the brain. Its critical role was further supported by its reduced levels in the brain of Alzheimer's disease (AD) patients. This agrees with a potential role of DHA in memory, learning and cognitive processes. Since there is yet no cure for dementia such as AD, there is growing interest in the role of DHA-supplemented diet in the prevention of AD pathogenesis. Accordingly, animal, epidemiological, preclinical and clinical studies indicated that DHA has neuroprotective effects in a number of neurodegenerative conditions including AD. The beneficial effects of this key omega-3 fatty acid supplementation may depend on the stage of disease progression, other dietary mediators and the apolipoprotein ApoE genotype. Herein, our review investigates, from animal and cell culture studies, the molecular mechanisms involved in the neuroprotective potential of DHA with emphasis on AD.
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Affiliation(s)
- Mounir Belkouch
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France.
| | - Mayssa Hachem
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France
| | - Abdeljalil Elgot
- Laboratoire des Sciences et Technologies de la Santé, Unité des Sciences Biomédicales, Institut Supérieur des Sciences de la Santé, Université Hassan 1er, Settat, Morocco
| | - Amanda Lo Van
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France
| | - Madeleine Picq
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France
| | - Michel Guichardant
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France
| | - Michel Lagarde
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France
| | - Nathalie Bernoud-Hubac
- Université de Lyon, UMR INSERM 1060, UMR INRA 1397, IMBL/INSA-Lyon, Cardiovasculaire, Métabolisme, Diabétologie et Nutrition Laboratory, Bât Louis Pasteur, INSA, Villeurbanne, France
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Abstract
Epidemiologic and experimental data suggest the involvement of cholesterol metabolism in the development and progression of Alzheimer disease and Niemann-Pick type C disease, but not of frontotemporal dementias. In these 3 neurodegenerative diseases, however, protein tau hyperphosphorylation and aggregation into neurofibrillary tangles are observed. To elucidate the relationship between cholesterol and tau, we compared sterol levels of neurons burdened with neurofibrillary tangles with those of their unaffected neighbors using semiquantitative filipin fluorescence microscopy in mice expressing P301L mutant human tau (a well-described model of FTDP-17) and in P301L transgenic mice lacking apolipoprotein E (the major cholesterol transporter in the brain). Cellular unesterified cholesterol was higher in neurons affected by tau pathology irrespective of apolipoprotein E deficiency. This argues for an impact of tau pathology on cellular cholesterol homeostasis. We suggest that there is a bidirectional mode of action: Disturbances in cellular cholesterol metabolism may promote tau pathology, but tau pathology may also alter neuronal cholesterol homeostasis; once it is established, a vicious cycle may promote neurofibrillary tangle formation.
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Sun JH, Yu JT, Tan L. The Role of Cholesterol Metabolism in Alzheimer’s Disease. Mol Neurobiol 2014; 51:947-65. [DOI: 10.1007/s12035-014-8749-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 05/07/2014] [Indexed: 12/25/2022]
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20
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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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The impact of cholesterol, DHA, and sphingolipids on Alzheimer's disease. BIOMED RESEARCH INTERNATIONAL 2014; 2013:814390. [PMID: 24575399 PMCID: PMC3929518 DOI: 10.1155/2013/814390] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 07/13/2013] [Indexed: 12/14/2022]
Abstract
Alzheimer's disease (AD) is a devastating neurodegenerative disorder currently affecting over 35 million people worldwide. Pathological hallmarks of AD are massive amyloidosis, extracellular senile plaques, and intracellular neurofibrillary tangles accompanied by an excessive loss of synapses. Major constituents of senile plaques are 40–42 amino acid long peptides termed β-amyloid (Aβ). Aβ is produced by sequential proteolytic processing of the amyloid precursor protein (APP). APP processing and Aβ production have been one of the central scopes in AD research in the past. In the last years, lipids and lipid-related issues are more frequently discussed to contribute to the AD pathogenesis. This review summarizes lipid alterations found in AD postmortem brains, AD transgenic mouse models, and the current understanding of how lipids influence the molecular mechanisms leading to AD and Aβ generation, focusing especially on cholesterol, docosahexaenoic acid (DHA), and sphingolipids/glycosphingolipids.
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Walter J, van Echten-Deckert G. Cross-talk of membrane lipids and Alzheimer-related proteins. Mol Neurodegener 2013; 8:34. [PMID: 24148205 PMCID: PMC4016522 DOI: 10.1186/1750-1326-8-34] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 09/25/2013] [Indexed: 12/18/2022] Open
Abstract
Alzheimer’s disease (AD) is neuropathologically characterized by the combined occurrence of extracellular β-amyloid plaques and intracellular neurofibrillary tangles in the brain. While plaques contain aggregated forms of the amyloid β-peptide (Aβ), tangles are formed by fibrillar forms of the microtubule associated protein tau. All mutations identified so far to cause familial forms of early onset AD (FAD) are localized close to or within the Aβ domain of the amyloid precursor protein (APP) or in the presenilin proteins that are essential components of a protease complex involved in the generation of Aβ. Mutations in the tau gene are not associated with FAD, but can cause other forms of dementia. The genetics of FAD together with biochemical and cell biological data, led to the formulation of the amyloid hypothesis, stating that accumulation and aggregation of Aβ is the primary event in the pathogenesis of AD, while tau might mediate its toxicity and neurodegeneration. The generation of Aβ involves sequential proteolytic cleavages of the amyloid precursor protein (APP) by enzymes called β-and γ-secretases. Notably, APP itself as well as the secretases are integral membrane proteins. Thus, it is very likely that membrane lipids are involved in the regulation of subcellular transport, activity, and metabolism of AD related proteins. Indeed, several studies indicate that membrane lipids, including cholesterol and sphingolipids (SLs) affect Aβ generation and aggregation. Interestingly, APP and other AD associated proteins, including β-and γ-secretases can, in turn, influence lipid metabolic pathways. Here, we review the close connection of cellular lipid metabolism and AD associated proteins and discuss potential mechanisms that could contribute to initiation and progression of AD.
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Affiliation(s)
- Jochen Walter
- Department of Neurology, University of Bonn, Sigmund-Freud-Str, 25, 53127, Bonn, Germany.
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Popp J, Meichsner S, Kölsch H, Lewczuk P, Maier W, Kornhuber J, Jessen F, Lütjohann D. Cerebral and extracerebral cholesterol metabolism and CSF markers of Alzheimer's disease. Biochem Pharmacol 2013; 86:37-42. [DOI: 10.1016/j.bcp.2012.12.007] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 12/11/2012] [Accepted: 12/11/2012] [Indexed: 11/28/2022]
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Leoni V, Caccia C. Potential diagnostic applications of side chain oxysterols analysis in plasma and cerebrospinal fluid. Biochem Pharmacol 2013; 86:26-36. [DOI: 10.1016/j.bcp.2013.03.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 03/18/2013] [Accepted: 03/20/2013] [Indexed: 12/20/2022]
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Barbero-Camps E, Fernández A, Martínez L, Fernández-Checa JC, Colell A. APP/PS1 mice overexpressing SREBP-2 exhibit combined Aβ accumulation and tau pathology underlying Alzheimer's disease. Hum Mol Genet 2013; 22:3460-76. [PMID: 23648430 DOI: 10.1093/hmg/ddt201] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Current evidence indicates that excess brain cholesterol regulates amyloid-β (Aβ) deposition, which in turn can regulate cholesterol homeostasis. Moreover, Aβ neurotoxicity is potentiated, in part, by mitochondrial glutathione (mGSH) depletion. To better understand the relationship between alterations in cholesterol homeostasis and Alzheimer's disease (AD), we generated a triple transgenic mice featuring sterol regulatory element-binding protein-2 (SREBP-2) overexpression in combination with APPswe/PS1ΔE9 mutations (APP/PS1) to examine key biochemical and functional characteristics of AD. Unlike APP/PS1 mice, APP/PS1/SREBP-2 mice exhibited early mitochondrial cholesterol loading and mGSH depletion. Moreover, β-secretase activation and Aβ accumulation, correlating with oxidative damage and neuroinflammation, were accelerated in APP/PS1/SREBP-2 mice compared with APP/PS1 mice. Triple transgenic mice displayed increased synaptotoxicity reflected by loss of synaptophysin and neuronal death, resulting in early object-recognition memory impairment associated with deficits in spatial memory. Interestingly, tau pathology was present in APP/PS1/SREBP-2 mice, manifested by increased tau hyperphosphorylation and cleavage, activation of tau kinases and neurofibrillary tangle (NFT) formation without expression of mutated tau. Importantly, in vivo treatment with the cell permeable GSH ethyl ester, which restored mGSH levels in APP/PS1/SREBP-2 mice, partially prevented the activation of tau kinases, reduced abnormal tau aggregation and Aβ deposition, resulting in attenuated synaptic degeneration. Taken together, these results show that cholesterol-mediated mGSH depletion is a key event in AD progression, accelerating the onset of key neuropathological hallmarks of the disease. Thus, therapeutic approaches to recover mGSH may represent a relevant strategy in the treatment of AD.
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Leboucher A, Laurent C, Fernandez-Gomez FJ, Burnouf S, Troquier L, Eddarkaoui S, Demeyer D, Caillierez R, Zommer N, Vallez E, Bantubungi K, Breton C, Pigny P, Buée-Scherrer V, Staels B, Hamdane M, Tailleux A, Buée L, Blum D. Detrimental effects of diet-induced obesity on τ pathology are independent of insulin resistance in τ transgenic mice. Diabetes 2013; 62:1681-8. [PMID: 23250356 PMCID: PMC3636620 DOI: 10.2337/db12-0866] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The τ pathology found in Alzheimer disease (AD) is crucial in cognitive decline. Midlife development of obesity, a major risk factor of insulin resistance and type 2 diabetes, increases the risk of dementia and AD later in life. The impact of obesity on AD risk has been suggested to be related to central insulin resistance, secondary to peripheral insulin resistance. The effects of diet-induced obesity (DIO) on τ pathology remain unknown. In this study, we evaluated effects of a high-fat diet, given at an early pathological stage, in the THY-Tau22 transgenic mouse model of progressive AD-like τ pathology. We found that early and progressive obesity potentiated spatial learning deficits as well as hippocampal τ pathology at a later stage. Surprisingly, THY-Tau22 mice did not exhibit peripheral insulin resistance. Further, pathological worsening occurred while hippocampal insulin signaling was upregulated. Together, our data demonstrate that DIO worsens τ phosphorylation and learning abilities in τ transgenic mice independently from peripheral/central insulin resistance.
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Affiliation(s)
- Antoine Leboucher
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Cyril Laurent
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Francisco-José Fernandez-Gomez
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Sylvie Burnouf
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Laetitia Troquier
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Sabiha Eddarkaoui
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Dominique Demeyer
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Raphaëlle Caillierez
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Nadège Zommer
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Emmanuelle Vallez
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U1011, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Kadiombo Bantubungi
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U1011, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Christophe Breton
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- EA 4489, Environnement Perinatal et Croissance, Lille, France
| | - Pascal Pigny
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
- Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - Valérie Buée-Scherrer
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Bart Staels
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U1011, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Malika Hamdane
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
| | - Anne Tailleux
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U1011, Lille, France
- Institut Pasteur de Lille, Lille, France
| | - Luc Buée
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
- Centre Hospitalier Régional Universitaire de Lille, Lille, France
| | - David Blum
- Université Lille-Nord de France, Université du Droit et de la Santé de Lille, Lille, France
- INSERM U837, Jean-Pierre Aubert Research Centre, Institut de Médecine Prédictive et de Recherche Thérapeutique, Lille, France
- Centre Hospitalier Régional Universitaire de Lille, Lille, France
- Corresponding author: David Blum,
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Kang J, Rivest S. Lipid metabolism and neuroinflammation in Alzheimer's disease: a role for liver X receptors. Endocr Rev 2012; 33:715-46. [PMID: 22766509 DOI: 10.1210/er.2011-1049] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Liver X receptors (LXR) are nuclear receptors that have emerged as key regulators of lipid metabolism. In addition to their functions as cholesterol sensors, LXR have also been found to regulate inflammatory responses in macrophages. Alzheimer's disease (AD) is a neurodegenerative disease characterized by a progressive cognitive decline associated with inflammation. Evidence indicates that the initiation and progression of AD is linked to aberrant cholesterol metabolism and inflammation. Activation of LXR can regulate neuroinflammation and decrease amyloid-β peptide accumulation. Here, we highlight the role of LXR in orchestrating lipid homeostasis and neuroinflammation in the brain. In addition, diabetes mellitus is also briefly discussed as a significant risk factor for AD because of the appearing beneficial effects of LXR on glucose homeostasis. The ability of LXR to attenuate AD pathology makes them potential therapeutic targets for this neurodegenerative disease.
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Affiliation(s)
- Jihong Kang
- Department of Physiology and Pathophysiology and Key Laboratory of Molecular Cardiovascular Sciences, State Education Ministry, Peking University Health Science Center, Beijing 100191, China
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Ambegaokar SS, Jackson GR. Functional genomic screen and network analysis reveal novel modifiers of tauopathy dissociated from tau phosphorylation. Hum Mol Genet 2011; 20:4947-77. [PMID: 21949350 PMCID: PMC3221533 DOI: 10.1093/hmg/ddr432] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A functional genetic screen using loss-of-function and gain-of-function alleles was performed to identify modifiers of tau-induced neurotoxicity using the 2N/4R (full-length) isoform of wild-type human tau expressed in the fly retina. We previously reported eye pigment mutations, which create dysfunctional lysosomes, as potent modifiers; here, we report 37 additional genes identified from ∼1900 genes screened, including the kinases shaggy/GSK-3beta, par-1/MARK, CamKI and Mekk1. Tau acts synergistically with Mekk1 and p38 to down-regulate extracellular regulated kinase activity, with a corresponding decrease in AT8 immunoreactivity (pS202/T205), suggesting that tau can participate in signaling pathways to regulate its own kinases. Modifiers showed poor correlation with tau phosphorylation (using the AT8, 12E8 and AT270 epitopes); moreover, tested suppressors of wild-type tau were equally effective in suppressing toxicity of a phosphorylation-resistant S11A tau construct, demonstrating that changes in tau phosphorylation state are not required to suppress or enhance its toxicity. Genes related to autophagy, the cell cycle, RNA-associated proteins and chromatin-binding proteins constitute a large percentage of identified modifiers. Other functional categories identified include mitochondrial proteins, lipid trafficking, Golgi proteins, kinesins and dynein and the Hsp70/Hsp90-organizing protein (Hop). Network analysis uncovered several other genes highly associated with the functional modifiers, including genes related to the PI3K, Notch, BMP/TGF-β and Hedgehog pathways, and nuclear trafficking. Activity of GSK-3β is strongly upregulated due to TDP-43 expression, and reduced GSK-3β dosage is also a common suppressor of Aβ42 and TDP-43 toxicity. These findings suggest therapeutic targets other than mitigation of tau phosphorylation.
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Affiliation(s)
- Surendra S Ambegaokar
- Department of Neurology, University of Texas Medical Branch, 301 University Blvd., MRB 10.138, Galveston, TX 77555, USA
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