1
|
Heo JH, Jung HN, Roh E, Han KD, Kang JG, Lee SJ, Ihm SH. Association of remnant cholesterol with risk of dementia: a nationwide population-based cohort study in South Korea. THE LANCET. HEALTHY LONGEVITY 2024; 5:e524-e533. [PMID: 39068948 DOI: 10.1016/s2666-7568(24)00112-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 05/31/2024] [Accepted: 06/04/2024] [Indexed: 07/30/2024] Open
Abstract
BACKGROUND The association between remnant cholesterol (remnant-C) and cardiovascular disease risk is well established, but its association with dementia remains unclear. We aimed to examine this association using a large-scale population dataset. METHODS We did a nationwide, population-based cohort study in which we identified participants aged 40 years and older who underwent the national health examination in 2009 from South Korea's National Health Insurance Service. We excluded people who were younger than 40 years and those with a triglyceride concentration of 400 mg/dL or higher due to concerns regarding the accuracy of calculated low-density lipoprotein cholesterol concentration in individuals with extremely high triglyceride concentrations. People who were previously diagnosed with dementia before the index date, and those who had any missing variables were also excluded. To minimise the influence of possible reverse causation, we excluded individuals who had developed any type of dementia within 1 year of the baseline measurements. We calculated hazard ratios (HRs) for all-cause dementia, Alzheimer's disease, and vascular dementia in each quartile of remnant-C using the Cox proportional hazards model adjusted for age, sex, body-mass index, estimated glomerular filtration rate, income level, smoking status, alcohol consumption, regular exercise, diabetes, hypertension, statin and fibrate use, and total cholesterol concentrations. We also did subgroup analyses to investigate the association between remnant-C and the risk of dementia stratified by age, sex, obesity, glycaemic status (normoglycaemia, impaired fasting glucose, new-onset type 2 diabetes, type 2 diabetes with a duration of less than 5 years, and type 2 diabetes with a duration of 5 years or more), hypertension, chronic kidney disease, and dyslipidaemia, using likelihood ratio tests. FINDINGS 4 234 415 individuals who underwent the national health examination in 2009 were deemed eligible for inclusion. We excluded 1 612 819 individuals on the basis of age, triglyceride concentration, missing variables, or having dementia at baseline. We identified 2 621 596 participants aged 40 years and older (1 305 556 men and 1 316 040 women) who underwent the national health examination and followed them up until the date of any incident of dementia or the end of the study period of Dec 31, 2020. During a median follow-up of 10·3 years (IQR 10·1-10·6), 146 991 (5·6%) participants developed all-cause dementia, 117 739 (4·5%) developed Alzheimer's disease, and 14 536 (0·6%) developed vascular dementia. The risk of dementia increased progressively with higher remnant-C concentrations. Compared with the lowest quartile of remnant-C (quartile 1), HRs in the highest quartile (quartile 4) were 1·11 (95% CI 1·09-1·13) for all-cause dementia, 1·11 (1·08-1·13) for Alzheimer's disease, and 1·15 (1·09-1·21) for vascular dementia. Subgroup analyses revealed that the risk of dementia associated with high remnant-C concentrations was higher in middle-aged people aged 40-59 years than in older people. The risk of dementia associated with high concentrations of remnant-C was notably more pronounced in individuals with diabetes compared with those without diabetes, and the risk increased steeply with a longer duration of diabetes. INTERPRETATION Results showed that higher remnant-C concentrations were independently associated with increased risks of all-cause dementia, Alzheimer's disease, and vascular dementia. More research is needed to determine the mechanisms underlying this finding. Monitoring and managing higher concentrations of remnant-C might have important implications for reducing the risk of dementia. FUNDING None.
Collapse
Affiliation(s)
- Ji Hye Heo
- Department of Internal Medicine, Hallym University College of Medicine, Gangwon-do, South Korea
| | - Han Na Jung
- Department of Internal Medicine, Hallym University College of Medicine, Gangwon-do, South Korea
| | - Eun Roh
- Department of Internal Medicine, Hallym University College of Medicine, Gangwon-do, South Korea
| | - Kyung-do Han
- Department of Statistics and Actuarial Science, Soongsil University, Seoul, South Korea
| | - Jun Goo Kang
- Department of Internal Medicine, Hallym University College of Medicine, Gangwon-do, South Korea.
| | - Seong Jin Lee
- Department of Internal Medicine, Hallym University College of Medicine, Gangwon-do, South Korea
| | - Sung-Hee Ihm
- Department of Internal Medicine, Hallym University College of Medicine, Gangwon-do, South Korea
| |
Collapse
|
2
|
Su H, Masters CL, Bush AI, Barnham KJ, Reid GE, Vella LJ. Exploring the significance of lipids in Alzheimer's disease and the potential of extracellular vesicles. Proteomics 2024; 24:e2300063. [PMID: 37654087 DOI: 10.1002/pmic.202300063] [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: 05/12/2023] [Revised: 08/07/2023] [Accepted: 08/14/2023] [Indexed: 09/02/2023]
Abstract
Lipids play a significant role in maintaining central nervous system (CNS) structure and function, and the dysregulation of lipid metabolism is known to occur in many neurological disorders, including Alzheimer's disease. Here we review what is currently known about lipid dyshomeostasis in Alzheimer's disease. We propose that small extracellular vesicle (sEV) lipids may provide insight into the pathophysiology and progression of Alzheimer's disease. This stems from the recognition that sEV likely contributes to disease pathogenesis, but also an understanding that sEV can serve as a source of potential biomarkers. While the protein and RNA content of sEV in the CNS diseases have been studied extensively, our understanding of the lipidome of sEV in the CNS is still in its infancy.
Collapse
Affiliation(s)
- Huaqi Su
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - Colin L Masters
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
| | - Ashley I Bush
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
| | - Kevin J Barnham
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
| | - Gavin E Reid
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
| | - Laura J Vella
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
- Department of Surgery, The Royal Melbourne Hospital, The University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
3
|
Luo YX, Yang LL, Yao XQ. Gut microbiota-host lipid crosstalk in Alzheimer's disease: implications for disease progression and therapeutics. Mol Neurodegener 2024; 19:35. [PMID: 38627829 PMCID: PMC11020986 DOI: 10.1186/s13024-024-00720-0] [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: 12/12/2023] [Accepted: 03/18/2024] [Indexed: 04/19/2024] Open
Abstract
Trillions of intestinal bacteria in the human body undergo dynamic transformations in response to physiological and pathological changes. Alterations in their composition and metabolites collectively contribute to the progression of Alzheimer's disease. The role of gut microbiota in Alzheimer's disease is diverse and complex, evidence suggests lipid metabolism may be one of the potential pathways. However, the mechanisms that gut microbiota mediate lipid metabolism in Alzheimer's disease pathology remain unclear, necessitating further investigation for clarification. This review highlights the current understanding of how gut microbiota disrupts lipid metabolism and discusses the implications of these discoveries in guiding strategies for the prevention or treatment of Alzheimer's disease based on existing data.
Collapse
Affiliation(s)
- Ya-Xi Luo
- Department of Rehabilitation, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ling-Ling Yang
- Department of Rehabilitation, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiu-Qing Yao
- Department of Rehabilitation, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
- Chongqing Municipality Clinical Research Center for Geriatric Medicine, Chongqing, China.
- Department of Rehabilitation Therapy, Chongqing Medical University, Chongqing, China.
| |
Collapse
|
4
|
Valencia-Olvera AC, Balu D, Moore A, Shah M, Ainis R, Xiang B, Saleh Y, Cai D, LaDu MJ, Tai LM. APOE2 Heterozygosity Reduces Hippocampal Soluble Amyloid-β42 Levels in Non-Hyperlipidemic Mice. J Alzheimers Dis 2024; 97:1629-1639. [PMID: 38306049 DOI: 10.3233/jad-231210] [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] [Indexed: 02/03/2024]
Abstract
APOE2 lowers Alzheimer's disease (AD) risk; unfortunately, the mechanism remains poorly understood and the use of mice models is problematic as APOE2 homozygosity is associated with hyperlipidemia. In this study, we developed mice that are heterozygous for APOE2 and APOE3 or APOE4 and overexpress amyloid-β peptide (Aβ) (EFAD) to evaluate the effect of APOE2 dosage on Aβ pathology. We found that heterozygous mice do not exhibit hyperlipidemia. Hippocampal but not cortical levels of soluble Aβ42 followed the order E2/2FAD > E2/3FAD≤E3/3FAD and E2/2FAD > E2/4FAD < E4/4FAD without an effect on insoluble Aβ42. These findings offer initial insights on the impact of APOE2 on Aβ pathology.
Collapse
Affiliation(s)
- Ana C Valencia-Olvera
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Deebika Balu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | | | - Maitri Shah
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Rebecca Ainis
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | | | - Yaseen Saleh
- University of Miami/Jackson Healthcare System, Miami, FL, USA
| | - Dongming Cai
- Alzheimer Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Research and Development Service, James J. Peters VA Medical Center, Bronx, NY, USA
- Department of Neurology, N. Bud Grossman Center for Memory Research and Care, University of Minnesota, Minneapolis, MN, USA
- Geriatric Research Education and Clinical Center (GRECC), Minneapolis VA Health Care System, Minneapolis, MN, USA
| | - Mary Jo LaDu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Leon M Tai
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| |
Collapse
|
5
|
Zhao T, Miao H, Song Z, Li Y, Xia N, Zhang Z, Zhang H. Metformin alleviates the cognitive impairment induced by benzo[a]pyrene via glucolipid metabolism regulated by FTO/FoxO6 pathway in mice. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:69192-69204. [PMID: 37133670 DOI: 10.1007/s11356-023-27303-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 04/25/2023] [Indexed: 05/04/2023]
Abstract
Benzo[a]pyrene (B[a]P) is neurotoxic; however, the mechanism and prevention are still unclear. In this study, we assessed the intervention effect of metformin (MET) on cognitive dysfunction in mice induced by B[a]P from the perspective of glucolipid metabolism. Forty-two male healthy ICR mice were randomly categorized into 6 groups and were gavaged with B[a]P (0, 2.5, 5, or 10 mg/kg), 45 times for 90 days. The controls were gavaged with edible peanut oil, and the intervention groups were co-treated with B[a]P (10 mg/kg) and MET (200 or 300 mg/kg). We assessed the cognitive function of mice, observed the pathomorphological and ultrastructural changes, and detected neuronal apoptosis and glucolipid metabolism. Results showed that B[a]P dose-dependently induced cognitive impairment, neuronal damage, glucolipid metabolism disorder in mice, and enhanced proteins of fat mass and obesity-associated protein (FTO) and forkhead box protein O6 (FoxO6) in the cerebral cortex and liver, which were alleviated by the MET intervention. The findings indicated the critical role of glucolipid metabolism disorder in the cognitive impairment in mice caused by B[a]P and the prevention of MET against B[a]P neurotoxicity by regulating glucolipid metabolism via restraining FTO/FoxO6 pathway. The finding provides a scientific basis for the neurotoxicity and prevention strategies of B[a]P.
Collapse
Affiliation(s)
- Tingyi Zhao
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China
| | - Huide Miao
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China
| | - Zhanfei Song
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China
| | - Yangyang Li
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China
| | - Na Xia
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China
| | - Zhiyan Zhang
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China
| | - Hongmei Zhang
- Department of Environmental Health, School of Public Health, Shanxi Medical University, 56 Xinjian South Road, Taiyuan, 030001, Shanxi, China.
- Key Laboratory of Coal Environmental Pathogenicity and Prevention, Ministry of Education, Taiyuan, China.
| |
Collapse
|
6
|
Villarreal J, Kow K, Pham B, Egatz-Gomez A, Sandrin TR, Coleman PD, Ros A. Intracellular Amyloid-β Detection from Human Brain Sections Using a Microfluidic Immunoassay in Tandem with MALDI-MS. Anal Chem 2023; 95:5522-5531. [PMID: 36894164 PMCID: PMC10078609 DOI: 10.1021/acs.analchem.2c03825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 02/23/2023] [Indexed: 03/11/2023]
Abstract
Alzheimer's disease (AD) currently affects more than 30 million people worldwide. The lack of understanding of AD's physiopathology limits the development of therapeutic and diagnostic tools. Soluble amyloid-β peptide (Aβ) oligomers that appear as intermediates along the Aβ aggregation into plaques are considered among the main AD neurotoxic species. Although a wealth of data are available about Aβ from in vitro and animal models, there is little known about intracellular Aβ in human brain cells, mainly due to the lack of technology to assess the intracellular protein content. The elucidation of the Aβ species in specific brain cell subpopulations can provide insight into the role of Aβ in AD and the neurotoxic mechanism involved. Here, we report a microfluidic immunoassay for in situ mass spectrometry analysis of intracellular Aβ species from archived human brain tissue. This approach comprises the selective laser dissection of individual pyramidal cell bodies from tissues, their transfer to the microfluidic platform for sample processing on-chip, and mass spectrometric characterization. As a proof-of-principle, we demonstrate the detection of intracellular Aβ species from as few as 20 human brain cells.
Collapse
Affiliation(s)
- Jorvani
Cruz Villarreal
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Center
for Applied Structural Discovery, The Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States
| | - Keegan Kow
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Center
for Applied Structural Discovery, The Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States
| | - Brian Pham
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Center
for Applied Structural Discovery, The Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States
| | - Ana Egatz-Gomez
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Center
for Applied Structural Discovery, The Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States
| | - Todd R. Sandrin
- School
of Mathematical and Natural Sciences, Arizona
State University, Glendale, Arizona 85306, United States
- Julie
Ann Wrigley Global Futures Laboratory, Arizona
State University, Glendale, Arizona 85306, United States
| | - Paul D. Coleman
- Banner
ASU Neurodegenerative Research Center, The Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States
| | - Alexandra Ros
- School
of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
- Center
for Applied Structural Discovery, The Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States
| |
Collapse
|
7
|
Lyubchenko YL. Protein Self-Assembly at the Liquid-Surface Interface. Surface-Mediated Aggregation Catalysis. J Phys Chem B 2023; 127:1880-1889. [PMID: 36812408 DOI: 10.1021/acs.jpcb.2c09029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Protein self-assembly into aggregates of various morphologies is a ubiquitous phenomenon in physical chemistry and biophysics. The critical role of amyloid assemblies in the development of diseases, neurodegenerative diseases especially, highlights the importance of understanding the mechanistic picture of the self-assembly process. The translation of this knowledge to the development of efficient preventions and treatments for diseases requires designing experiments at conditions mimicking those in vivo. This Perspective reviews data satisfying two major requirements: membrane environment and physiologically low concentrations of proteins. Recent progress in experiments and computational modeling resulted in a novel model for the amyloid aggregation process at the membrane-liquid interface. The self-assembly under such conditions has a number of critical features, further understanding of which can lead to the development of efficient preventive means and treatments for Alzheimer's and other devastating neurodegenerative disorders.
Collapse
Affiliation(s)
- Yuri L Lyubchenko
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| |
Collapse
|
8
|
Sharp FR, DeCarli CS, Jin LW, Zhan X. White matter injury, cholesterol dysmetabolism, and APP/Abeta dysmetabolism interact to produce Alzheimer's disease (AD) neuropathology: A hypothesis and review. Front Aging Neurosci 2023; 15:1096206. [PMID: 36845656 PMCID: PMC9950279 DOI: 10.3389/fnagi.2023.1096206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/30/2023] [Indexed: 02/12/2023] Open
Abstract
We postulate that myelin injury contributes to cholesterol release from myelin and cholesterol dysmetabolism which contributes to Abeta dysmetabolism, and combined with genetic and AD risk factors, leads to increased Abeta and amyloid plaques. Increased Abeta damages myelin to form a vicious injury cycle. Thus, white matter injury, cholesterol dysmetabolism and Abeta dysmetabolism interact to produce or worsen AD neuropathology. The amyloid cascade is the leading hypothesis for the cause of Alzheimer's disease (AD). The failure of clinical trials based on this hypothesis has raised other possibilities. Even with a possible new success (Lecanemab), it is not clear whether this is a cause or a result of the disease. With the discovery in 1993 that the apolipoprotein E type 4 allele (APOE4) was the major risk factor for sporadic, late-onset AD (LOAD), there has been increasing interest in cholesterol in AD since APOE is a major cholesterol transporter. Recent studies show that cholesterol metabolism is intricately involved with Abeta (Aβ)/amyloid transport and metabolism, with cholesterol down-regulating the Aβ LRP1 transporter and upregulating the Aβ RAGE receptor, both of which would increase brain Aβ. Moreover, manipulating cholesterol transport and metabolism in rodent AD models can ameliorate pathology and cognitive deficits, or worsen them depending upon the manipulation. Though white matter (WM) injury has been noted in AD brain since Alzheimer's initial observations, recent studies have shown abnormal white matter in every AD brain. Moreover, there is age-related WM injury in normal individuals that occurs earlier and is worse with the APOE4 genotype. Moreover, WM injury precedes formation of plaques and tangles in human Familial Alzheimer's disease (FAD) and precedes plaque formation in rodent AD models. Restoring WM in rodent AD models improves cognition without affecting AD pathology. Thus, we postulate that the amyloid cascade, cholesterol dysmetabolism and white matter injury interact to produce and/or worsen AD pathology. We further postulate that the primary initiating event could be related to any of the three, with age a major factor for WM injury, diet and APOE4 and other genes a factor for cholesterol dysmetabolism, and FAD and other genes for Abeta dysmetabolism.
Collapse
Affiliation(s)
- Frank R. Sharp
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
| | | | | | | |
Collapse
|
9
|
Papadopoulos N, Suelves N, Perrin F, Vadukul DM, Vrancx C, Constantinescu SN, Kienlen-Campard P. Structural Determinant of β-Amyloid Formation: From Transmembrane Protein Dimerization to β-Amyloid Aggregates. Biomedicines 2022; 10:2753. [PMID: 36359274 PMCID: PMC9687742 DOI: 10.3390/biomedicines10112753] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/18/2022] [Accepted: 10/21/2022] [Indexed: 10/03/2023] Open
Abstract
Most neurodegenerative diseases have the characteristics of protein folding disorders, i.e., they cause lesions to appear in vulnerable regions of the nervous system, corresponding to protein aggregates that progressively spread through the neuronal network as the symptoms progress. Alzheimer's disease is one of these diseases. It is characterized by two types of lesions: neurofibrillary tangles (NFTs) composed of tau proteins and senile plaques, formed essentially of amyloid peptides (Aβ). A combination of factors ranging from genetic mutations to age-related changes in the cellular context converge in this disease to accelerate Aβ deposition. Over the last two decades, numerous studies have attempted to elucidate how structural determinants of its precursor (APP) modify Aβ production, and to understand the processes leading to the formation of different Aβ aggregates, e.g., fibrils and oligomers. The synthesis proposed in this review indicates that the same motifs can control APP function and Aβ production essentially by regulating membrane protein dimerization, and subsequently Aβ aggregation processes. The distinct properties of these motifs and the cellular context regulate the APP conformation to trigger the transition to the amyloid pathology. This concept is critical to better decipher the patterns switching APP protein conformation from physiological to pathological and improve our understanding of the mechanisms underpinning the formation of amyloid fibrils that devastate neuronal functions.
Collapse
Affiliation(s)
- Nicolas Papadopoulos
- SIGN Unit, de Duve Institute, UCLouvain, 1200 Brussels, Belgium
- Ludwig Institute for Cancer Research Brussels, 1348 Brussels, Belgium
| | - Nuria Suelves
- Aging and Dementia Research Group, Cellular and Molecular (CEMO) Division, Institute of Neuroscience, UCLouvain, 1200 Brussels, Belgium
| | - Florian Perrin
- Memory Disorders Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Devkee M. Vadukul
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, London SW7 2BX, UK
| | - Céline Vrancx
- Laboratory for Membrane Trafficking, VIB-Center for Brain and Disease Research, KU Leuven, 3000 Leuven, Belgium
- Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium
| | - Stefan N. Constantinescu
- SIGN Unit, de Duve Institute, UCLouvain, 1200 Brussels, Belgium
- Ludwig Institute for Cancer Research Brussels, 1348 Brussels, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), 1300 Wavre, Belgium
- Nuffield Department of Medicine, Ludwig Institute for Cancer Research, Oxford University, Oxford OX1 2JD, UK
| | - Pascal Kienlen-Campard
- Aging and Dementia Research Group, Cellular and Molecular (CEMO) Division, Institute of Neuroscience, UCLouvain, 1200 Brussels, Belgium
| |
Collapse
|
10
|
Rudajev V, Novotny J. Cholesterol as a key player in amyloid β-mediated toxicity in Alzheimer’s disease. Front Mol Neurosci 2022; 15:937056. [PMID: 36090253 PMCID: PMC9453481 DOI: 10.3389/fnmol.2022.937056] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder that is one of the most devastating and widespread diseases worldwide, mainly affecting the aging population. One of the key factors contributing to AD-related neurotoxicity is the production and aggregation of amyloid β (Aβ). Many studies have shown the ability of Aβ to bind to the cell membrane and disrupt its structure, leading to cell death. Because amyloid damage affects different parts of the brain differently, it seems likely that not only Aβ but also the nature of the membrane interface with which the amyloid interacts, helps determine the final neurotoxic effect. Because cholesterol is the dominant component of the plasma membrane, it plays an important role in Aβ-induced toxicity. Elevated cholesterol levels and their regulation by statins have been shown to be important factors influencing the progression of neurodegeneration. However, data from many studies have shown that cholesterol has both neuroprotective and aggravating effects in relation to the development of AD. In this review, we attempt to summarize recent findings on the role of cholesterol in Aβ toxicity mediated by membrane binding in the pathogenesis of AD and to consider it in the broader context of the lipid composition of cell membranes.
Collapse
|
11
|
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.
Collapse
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,
| |
Collapse
|
12
|
Bai X, Mai M, Yao K, Zhang M, Huang Y, Zhang W, Guo X, Xu Y, Zhang Y, Qurban A, Duan L, Bu J, Zhang J, Wu J, Zhao Y, Yuan X, Zu H. The role of DHCR24 in the pathogenesis of AD: re-cognition of the relationship between cholesterol and AD pathogenesis. Acta Neuropathol Commun 2022; 10:35. [PMID: 35296367 PMCID: PMC8925223 DOI: 10.1186/s40478-022-01338-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 02/27/2022] [Indexed: 02/01/2023] Open
Abstract
Previous studies show that 3β-hydroxysterol-Δ24 reductase (DHCR24) has a remarked decline in the brain of AD patients. In brain cholesterol synthetic metabolism, DHCR24 is known as the heavily key synthetase in cholesterol synthesis. Moreover, mutations of DHCR24 gene result in inhibition of the enzymatic activity of DHCR24, causing brain cholesterol deficiency and desmosterol accumulation. Furthermore, in vitro studies also demonstrated that DHCR24 knockdown lead to the inhibition of cholesterol synthesis, and the decrease of plasma membrane cholesterol and intracellular cholesterol level. Obviously, DHCR24 could play a crucial role in maintaining cholesterol homeostasis via the control of cholesterol synthesis. Over the past two decades, accumulating data suggests that DHCR24 activity is downregulated by major risk factors for AD, suggesting a potential link between DHCR24 downregulation and AD pathogenesis. Thus, the brain cholesterol loss seems to be induced by the major risk factors for AD, suggesting a possible causative link between brain cholesterol loss and AD. According to previous data and our study, we further found that the reduced cholesterol level in plasma membrane and intracellular compartments by the deficiency of DHCR24 activity obviously was involved in β-amyloid generation, tau hyperphosphorylation, apoptosis. Importantly, increasing evidences reveal that the brain cholesterol loss and lipid raft disorganization are obviously linked to neuropathological impairments which are associated with AD pathogenesis. Therefore, based on previous data and research on DHCR24, we suppose that the brain cholesterol deficiency/loss might be involved in the pathogenesis of AD.
Collapse
|
13
|
Lin Y, Peng X, Lin X, Deng X, Liu F, Tao H, Dong R, Wang B, Bi Y. Potential Value of Serum Lipid in the Identication of Postoperative Delirium Undergoing Knee/Hip Arthroplasty: The Perioperative Neurocognitive Disorder and Biomarker Lifestyle Study. Front Psychiatry 2022; 13:870317. [PMID: 35492710 PMCID: PMC9039337 DOI: 10.3389/fpsyt.2022.870317] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 03/18/2022] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE We aimed to investigate the relationship between preoperative lipid level and postoperative delirium (POD) and explore whether lipid's effect on POD is mediated by POD core protein. METHODS A total of 635 patients who were planned to undergo knee/hip arthroplasty under combined spinal-epidural anesthesia, regardless of gender, were selected. The patients were aged 40-90 years with American Society of Anesthesiologists physical status I II. The Mini-Mental State Examination (MMSE) was completed 1 day before the operation. Five milliliter elbow venous blood was taken from the patients before anesthesia, and serum levels of total cholesterol (TG), triglyceride (TC), low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C) were detected. Cerebrospinal fluid (CSF) was extracted after successful spinal-epidural combined puncture, and amyloid beta40 (Aβ40), amyloid beta42 (Aβ42), total Tau (t-Tau), and phosphorylated Tau (p-Tau) in the CSF were measured by enzyme-linked immunosorbent assays (ELISA). After the operation, the occurrence and severity of POD were assessed using the Confusion Assessment Method and the Memorial Delirium Assessment Scale (MDAS), respectively. Patients were categorized into POD group and NPOD group. Logistic regression was used to analyze the relationship between POD and TC, TG, LDL-C, and HDL-C, and the mediating effect was used to analyze the role of POD core proteins in the relationship between lipid and MDAS. We used the receiver operating characteristic (ROC) and the precision-recall curve (PRC) analysis to assess the ability of TC, TG, LDL-C, and HDL-C ability to predict POD. Finally, we performed a sensitivity analysis to assess the stability of the results. RESULTS A total of 562 patients were finally enrolled in this study, and 66 patients developed POD, with an incidence of 11.7%. Logistic regression analysis showed that high concentration of TC (OR = 3.148, 95%CI 1.858∼5.333, P < 0.001), TG (OR = 2.483, 95%CI 1.573∼3.918, P < 0.001), and LDL-C (OR = 2.469, 95%CI 1.310∼4.656, P = 0.005) in serum were risk factors for POD. A high concentration of HDL-C (OR = 0.258, 95%CI 0.112∼0.594, P = 0.001) was a protective factor for POD after adjusted for age, sex, education, and MMSE score. ROC curves showed that HDL-C have the highest sensitivity and specificity in predicting POD. For these four lipid markers, the PRC range from 0.602 to 0.731, respectively. The mediating analysis showed that POD core proteins could partially mediate the relationship between lipid and POD (effect value: 16.19∼91.04%). The results were barely changed in the sensitivity analysis, and the sensitivity analysis has shown that the results were stable. CONCLUSION The increase of serum TG, TC, and LDL-C concentration is a risk factor for POD development, while high HDL-C concentration is a protective factor for POD, and the occurrence of POD is caused by hyperlipidemia may be caused by POD core proteins. CLINICAL TRIAL REGISTRATION [www.ClinicalTrials.gov], identifier [Chictr200033439].
Collapse
Affiliation(s)
- Yanan Lin
- Department of Anesthesiology, Qingdao Municipal Hospital Affiliated to Qingdao University, Qingdao, China
| | - Xiaoyan Peng
- Department of Anesthesiology, Qingdao Municipal Hospital Affiliated to Qingdao University, Qingdao, China
| | - Xu Lin
- Department of Anesthesiology, Qingdao Municipal Hospital Affiliated to Qingdao University, Qingdao, China
| | - Xiyuan Deng
- Department of Anesthesiology, Dalian Medical University, Dalian, China
| | - Fanghao Liu
- Department of Anesthesiology, Qingdao Municipal Hospital Affiliated to Qingdao University, Qingdao, China
| | - He Tao
- Department of Anesthesiology, Dalian Medical University, Dalian, China
| | - Rui Dong
- Department of Anesthesiology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Bin Wang
- Department of Anesthesiology, Qingdao Municipal Hospital Affiliated to Qingdao University, Qingdao, China
| | - Yanlin Bi
- Department of Anesthesiology, Qingdao Municipal Hospital Affiliated to Qingdao University, Qingdao, China
| |
Collapse
|
14
|
Sánchez-Melgar A, Izquierdo-Ramírez PJ, Palomera-Ávalos V, Pallàs M, Albasanz JL, Martín M. High-Fat and Resveratrol Supplemented Diets Modulate Adenosine Receptors in the Cerebral Cortex of C57BL/6J and SAMP8 Mice. Nutrients 2021; 13:nu13093040. [PMID: 34578918 PMCID: PMC8466958 DOI: 10.3390/nu13093040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 12/16/2022] Open
Abstract
Neurodegenerative disorders are devastating diseases in which aging is a major risk factor. High-fat diet (HFD) seems to contribute to cognition deterioration, but the underlying mechanisms are poorly understood. Moreover, resveratrol (RSV) has been reported to counteract the loss of cognition associated with age. Our study aimed to investigate whether the adenosinergic system and plasma membrane cholesterol are modulated by HFD and RSV in the cerebral cortex of C57BL/6J and SAMP8 mice. Results show that HFD induced increased A1R and A2AR densities in C57BL/6J, whereas this remained unchanged in SAMP8. Higher activity of 5′-Nucleotidase was found as a common effect induced by HFD in both mice strains. Furthermore, the effect of HFD and RSV on A2BR density was different depending on the mouse strain. RSV did not clearly counteract the HFD-induced effects on the adenosinergic system. Besides, no changes in free-cholesterol levels were detected in the plasma membrane of cerebral cortex in both strains. Taken together, our data suggest a different modulation of adenosine receptors depending on the mouse strain, not related to changes in plasma membrane cholesterol content.
Collapse
Affiliation(s)
- Alejandro Sánchez-Melgar
- Regional Center of Biomedical Research, Department of Inorganic, Organic and Biochemistry, Faculty of Chemical and Technological Sciences, School of Medicine of Ciudad Real, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain; (A.S.-M.); (P.J.I.-R.); (M.M.)
| | - Pedro José Izquierdo-Ramírez
- Regional Center of Biomedical Research, Department of Inorganic, Organic and Biochemistry, Faculty of Chemical and Technological Sciences, School of Medicine of Ciudad Real, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain; (A.S.-M.); (P.J.I.-R.); (M.M.)
| | - Verónica Palomera-Ávalos
- Department of Pharmacology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, Institute of Neuroscience, University of Barcelona, 08028 Barcelona, Spain; (V.P.-Á.); (M.P.)
| | - Mercè Pallàs
- Department of Pharmacology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, Institute of Neuroscience, University of Barcelona, 08028 Barcelona, Spain; (V.P.-Á.); (M.P.)
| | - José Luis Albasanz
- Regional Center of Biomedical Research, Department of Inorganic, Organic and Biochemistry, Faculty of Chemical and Technological Sciences, School of Medicine of Ciudad Real, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain; (A.S.-M.); (P.J.I.-R.); (M.M.)
- Correspondence:
| | - Mairena Martín
- Regional Center of Biomedical Research, Department of Inorganic, Organic and Biochemistry, Faculty of Chemical and Technological Sciences, School of Medicine of Ciudad Real, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain; (A.S.-M.); (P.J.I.-R.); (M.M.)
| |
Collapse
|
15
|
Biomarkers for evaluating the effects of exercise interventions in patients with MCI or dementia: A systematic review and meta-analysis. Exp Gerontol 2021; 151:111424. [PMID: 34051283 DOI: 10.1016/j.exger.2021.111424] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 04/13/2021] [Accepted: 05/23/2021] [Indexed: 11/20/2022]
Abstract
OBJECTIVES To summarize the biomarkers for evaluating the effects of exercise interventions in patients with cognitive impairment associated with aging, as well as their responses to exercise interventions. DESIGN A systematic review and meta-analysis METHODS: We systematically searched different electronic database, including PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, PsycINFO, SPORTDiscus up to April 2020. Clinical controlled trials with exercise interventions in patients with cognitive impairment were included. The main outcomes included all the biomarkers used to evaluate the effects of exercise interventions. If data for certain biomarkers was enough (more than 2 studies), meta-analyses would be performed to estimate the effect sizes by calculating the standard mean differences (SMDs) and 95% confidence intervals (CIs). RESULTS Finally, we included 33 articles from 26 trials. The biomarkers included neurotrophic factors, inflammatory factors, oxidative stress markers, neuropathological hallmarks, metabolic biomarkers and genotypes. The meta-analyses indicated that exercise significantly decreased the levels of IL-6 (SMD = -0.45; 95% CI: -0.72, -0.18) and low-density lipoprotein (SMD = -0.26; 95% CI: -0.50, -0.01). Subgroup analyses showed that aerobic exercise also could decrease the levels of TNF-α (SMD = -1.21; 95% CI: -2.29, -0.14). There were some important cognition-related biomarkers which were rarely measured, such as Aβ, tau and IGF-1. CONCLUSION Regular exercise showed positive effects on reducing inflammation and regulating lipid metabolism. But the available evidence is limited and more studies with different exercise interventions should be conducted to test the effects of exercise on other important cognition-related biomarkers in patients with cognitive dysfunction.
Collapse
|
16
|
Goldwaser EL, Acharya NK, Wu H, Godsey GA, Sarkar A, DeMarshall CA, Kosciuk MC, Nagele RG. Evidence that Brain-Reactive Autoantibodies Contribute to Chronic Neuronal Internalization of Exogenous Amyloid-β1-42 and Key Cell Surface Proteins During Alzheimer's Disease Pathogenesis. J Alzheimers Dis 2021; 74:345-361. [PMID: 32039847 PMCID: PMC7175946 DOI: 10.3233/jad-190962] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Blood-brain barrier (BBB) permeability is a recognized early feature of Alzheimer’s disease (AD). In the present study, we examined consequences of increased BBB permeability on the development of AD-related pathology by tracking selected leaked plasma components and their interactions with neurons in vivo and in vitro. Histological sections of cortical regions of postmortem AD brains were immunostained to determine the distribution of amyloid-β1-42 (Aβ42), cathepsin D, IgG, GluR2/3, and alpha7 nicotinic acetylcholine receptor (α7nAChR). Results revealed that chronic IgG binding to pyramidal neurons coincided with internalization of Aβ42, IgG, GluR2/3, and α7nAChR as well as lysosomal compartment expansion in these cells in regions of AD pathology. To test possible mechanistic interrelationships of these phenomena, we exposed differentiated SH-SY5Y neuroblastoma cells to exogenous, soluble Aβ42 peptide and serum from AD and control subjects. The rate and extent of Aβ42 internalization in these cells was enhanced by serum containing neuron-binding IgG autoantibodies. This was confirmed by treating cells with individual antibodies specific for α7nAChR, purified IgG from AD or non-AD sera, and sera devoid of IgG, in the presence of 100 nM Aβ42. Initial co-localization of IgG, α7nAChR, and Aβ42 was temporally and spatially linked to early endosomes (Rab11) and later to lysosomes (LAMP-1). Aβ42 internalization was attenuated by treatment with monovalent F(ab) antibody fragments generated from purified IgG from AD serum and then rescued by coupling F(ab) fragments with divalent human anti-Fab. Overall, results suggest that cross-linking of neuron-binding autoantibodies targeting cell surface proteins can accelerate intraneuronal Aβ42 deposition in AD.
Collapse
Affiliation(s)
- Eric L Goldwaser
- University of Maryland Medical Center and Sheppard Pratt Health System, Department of Psychiatry, Baltimore, MD, USA.,Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA
| | - Nimish K Acharya
- Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA.,Department of Geriatrics and Gerontology, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA
| | - Hao Wu
- Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA
| | - George A Godsey
- Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA
| | - Abhirup Sarkar
- Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA
| | - Cassandra A DeMarshall
- Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA
| | - Mary C Kosciuk
- Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Department of Geriatrics and Gerontology, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA
| | - Robert G Nagele
- Biomarker Discovery Center, New Jersey Institute for Successful Aging, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA.,Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ, USA.,Department of Geriatrics and Gerontology, Rowan University School of Osteopathic Medicine, Stratford, NJ, USA
| |
Collapse
|
17
|
Wiȩckowska-Gacek A, Mietelska-Porowska A, Chutorański D, Wydrych M, Długosz J, Wojda U. Western Diet Induces Impairment of Liver-Brain Axis Accelerating Neuroinflammation and Amyloid Pathology in Alzheimer's Disease. Front Aging Neurosci 2021; 13:654509. [PMID: 33867971 PMCID: PMC8046915 DOI: 10.3389/fnagi.2021.654509] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 03/05/2021] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease (AD) is an aging-dependent, irreversible neurodegenerative disorder and the most common cause of dementia. The prevailing AD hypothesis points to the central role of altered cleavage of amyloid precursor protein (APP) and formation of toxic amyloid-β (Aβ) deposits in the brain. The lack of efficient AD treatments stems from incomplete knowledge on AD causes and environmental risk factors. The role of lifestyle factors, including diet, in neurological diseases is now beginning to attract considerable attention. One of them is western diet (WD), which can lead to many serious diseases that develop with age. The aim of the study was to investigate whether WD-derived systemic disturbances may accelerate the brain neuroinflammation and amyloidogenesis at the early stages of AD development. To verify this hypothesis, transgenic mice expressing human APP with AD-causing mutations (APPswe) were fed with WD from the 3rd month of age. These mice were compared to APPswe mice, in which short-term high-grade inflammation was induced by injection of lipopolysaccharide (LPS) and to untreated APPswe mice. All experimental subgroups of animals were subsequently analyzed at 4-, 8-, and 12-months of age. APPswe mice at 4- and 8-months-old represent earlier pre-plaque stages of AD, while 12-month-old animals represent later stages of AD, with visible amyloid pathology. Already short time of WD feeding induced in 4-month-old animals such brain neuroinflammation events as enhanced astrogliosis, to a level comparable to that induced by the administration of pro-inflammatory LPS, and microglia activation in 8-month-old mice. Also, WD feeding accelerated increased Aβ production, observed already in 8-month-old animals. These brain changes corresponded to diet-induced metabolic disorders, including increased cholesterol level in 4-months of age, and advanced hypercholesterolemia and fatty liver disease in 8-month-old mice. These results indicate that the westernized pattern of nourishment is an important modifiable risk factor of AD development, and that a healthy, balanced, diet may be one of the most efficient AD prevention methods.
Collapse
Affiliation(s)
| | | | | | | | | | - Urszula Wojda
- Laboratory of Preclinical Testing of Higher Standard, Neurobiology Center, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| |
Collapse
|
18
|
Dimeric Transmembrane Orientations of APP/C99 Regulate γ-Secretase Processing Line Impacting Signaling and Oligomerization. iScience 2020; 23:101887. [PMID: 33367225 PMCID: PMC7749410 DOI: 10.1016/j.isci.2020.101887] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/21/2020] [Accepted: 11/25/2020] [Indexed: 12/22/2022] Open
Abstract
Amyloid precursor protein (APP) cleavage by the β-secretase produces the C99 transmembrane (TM) protein, which contains three dimerization-inducing Gly-x-x-x-Gly motifs. We demonstrate that dimeric C99 TM orientations regulate the precise cleavage lines by γ-secretase. Of all possible dimeric orientations imposed by a coiled-coil to the C99 TM domain, the dimer containing the 33Gly-x-x-x-Gly37 motif in the interface promoted the Aβ42 processing line and APP intracellular domain-dependent gene transcription, including the induction of BACE1 mRNA, enhancing amyloidogenic processing and signaling. Another orientation exhibiting the 25Gly-x-x-x-Gly29 motif in the interface favored processing to Aβ43/40. It induced significantly less gene transcription, while promoting formation of SDS-resistant "Aβ-like" oligomers, reminiscent of Aβ peptide oligomers. These required both Val24 of a pro-β motif and the 25Gly-x-x-x-Gly29 interface. Thus, crossing angles imposed by precise dimeric orientations control γ-secretase initial cleavage at Aβ48 or Aβ49, linking the former to enhanced signaling and Aβ42 production.
Collapse
|
19
|
Pera M, Montesinos J, Larrea D, Agrawal RR, Velasco KR, Stavrovskaya IG, Yun TD, Area-Gomez E. MAM and C99, key players in the pathogenesis of Alzheimer's disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2020; 154:235-278. [PMID: 32739006 DOI: 10.1016/bs.irn.2020.03.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Inter-organelle communication is a rapidly-expanding field that has transformed our understanding of cell biology and pathology. Organelle-organelle contact sites can generate transient functional domains that act as enzymatic hubs involved in the regulation of cellular metabolism and intracellular signaling. One of these hubs is located in areas of the endoplasmic reticulum (ER) connected to mitochondria, called mitochondria-associated ER membranes (MAM). These MAM are transient lipid rafts intimately involved in cholesterol and phospholipid metabolism, calcium homeostasis, and mitochondrial function and dynamics. In addition, γ-secretase-mediated proteolysis of the amyloid precursor protein 99-aa C-terminal fragment (C99) to form amyloid β also occurs at the MAM. Our most recent data indicates that in Alzheimer's disease, increases in uncleaved C99 levels at the MAM provoke the upregulation of MAM-resident functions, resulting in the loss of lipid homeostasis, and mitochondrial dysfunction. Here, we discuss the relevance of these findings in the field, and the contribution of C99 and MAM dysfunction to Alzheimer's disease neuropathology.
Collapse
Affiliation(s)
- Marta Pera
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States; Basic Sciences Department, Faculty of Medicine and Health Sciences, Universitat Internacional de Catalunya, Sant Cugat del Vallés, Barcelona, Spain.
| | - Jorge Montesinos
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY, United States
| | - Delfina Larrea
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
| | - Rishi R Agrawal
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, NY, United States
| | - Kevin R Velasco
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
| | - Irina G Stavrovskaya
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
| | - Taekyung D Yun
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States
| | - Estela Area-Gomez
- Department of Neurology, Columbia University Irving Medical Center, New York, NY, United States; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY, United States; Institute of Human Nutrition, Columbia University Irving Medical Center, New York, NY, United States.
| |
Collapse
|
20
|
Pratap AA, Holsinger RMD. Altered Brain Adiponectin Receptor Expression in the 5XFAD Mouse Model of Alzheimer's Disease. Pharmaceuticals (Basel) 2020; 13:E150. [PMID: 32664663 PMCID: PMC7407895 DOI: 10.3390/ph13070150] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/25/2020] [Accepted: 07/08/2020] [Indexed: 12/12/2022] Open
Abstract
Metabolic syndromes share common pathologies with Alzheimer's disease (AD). Adiponectin, an adipocyte-derived protein, regulates energy metabolism via its receptors, AdipoR1 and AdipoR2. To investigate the distribution of adiponectin receptors (AdipoRs) in Alzheimer's, we examined their expression in the aged 5XFAD mouse model of AD. In age-matched wild-type mice, we observed neuronal expression of both ARs throughout the brain as well as endothelial expression of AdipoR1. The pattern of receptor expression in the aged 5XFAD brain was significantly perturbed. Here, we observed decreased neuronal expression of both ARs and decreased endothelial expression of AdipoR1, but robust expression of AdipoR2 in activated astrocytes. We also observed AdipoR2-expressing astrocytes in the dorsomedial hypothalamic and thalamic mediodorsal nuclei, suggesting the possibility that astrocytes utilise AdipoR2 signalling to fuel their activated state in the AD brain. These findings provide further evidence of a metabolic disturbance and demonstrate a potential shift in energy utilisation in the AD brain, supporting imaging studies performed in AD patients.
Collapse
Affiliation(s)
- Anishchal A. Pratap
- Laboratory of Molecular Neuroscience and Dementia, Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia;
- Discipline of Pathology, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| | - R. M. Damian Holsinger
- Laboratory of Molecular Neuroscience and Dementia, Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia;
- Discipline of Pathology, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia
| |
Collapse
|
21
|
Mayagoitia K, Shin SD, Rubini M, Siebold L, Wilson CG, Bellinger DL, Figueroa JD, Soriano S. Short-term exposure to dietary cholesterol is associated with downregulation of interleukin-15, reduced thigmotaxis and memory impairment in mice. Behav Brain Res 2020; 393:112779. [PMID: 32585301 DOI: 10.1016/j.bbr.2020.112779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 05/15/2020] [Accepted: 06/16/2020] [Indexed: 02/08/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative condition associated with loss of memory function, depression and anxiety. The etiology of AD is poorly understood, but both cholesterol dyshomeostasis and dysregulation of the immune system are contributing factors. Current evidence is consistent with a detrimental effect of excess cholesterol on neuroinflammation, both in mouse models of memory loss and in dementia in humans. However, whether the impact of cholesterol on neuroinflammation occurs early and contributes to pathogenesis of the disease or simply reflects a pleiotropic impact at advanced stages of disease is unclear. To explore this question, we measured, in 9-13 week-old mice, cognitive status and changes in brain inflammatory mediators in response to a short-term high-cholesterol diet. We hypothesized that short-term exposure to excess dietary cholesterol would alter the early inflammatory responses associated with cognitive and/or behavioral impairment. We report that short-term exposure to a high-cholesterol diet led to decreased thigmotaxis and short-term spatial memory impairment without affecting long-term recognition memory. Furthermore, cognitive and behavioral phenotypes in these mice were associated with a reduction in interleukin-15 levels in the absence of changes in other inflammatory mediators. Our findings indicate that interleukin-15 may play a role in early stages of cognitive impairment secondary to hypercholesterolemia. Consequently, optimization of interleukin-15 signaling may be a viable effective cognitive therapy in the population susceptible to developing dementia due to risk factors associated with cholesterol dysregulation.
Collapse
Affiliation(s)
- Karina Mayagoitia
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Sam D Shin
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Marsilio Rubini
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Lorraine Siebold
- Lawrence D. Longo Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Christopher G Wilson
- Lawrence D. Longo Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Denise L Bellinger
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Johnny D Figueroa
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda CA, USA
| | - Salvador Soriano
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
| |
Collapse
|
22
|
Causal association of circulating cholesterol levels with dementia: a mendelian randomization meta-analysis. Transl Psychiatry 2020; 10:145. [PMID: 32398686 PMCID: PMC7217910 DOI: 10.1038/s41398-020-0822-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 04/21/2020] [Accepted: 04/28/2020] [Indexed: 12/23/2022] Open
Abstract
Prospective studies have shown that abnormally circulating cholesterol is associated with the risk of dementia. However, whether the association is causal or not remains unclear. We attempt to infer the causal association in a MR meta-analysis by using ApoE gene polymorphisms as instrument variables. Studies with dementia risk (27 studies) or circulating lipid levels (7 studies) were included, with totally 3136 dementia patients and 3103 healthy controls. The analyses showed that carriers of ε2 allele significantly were of decreased risk of AD (OR = 0.70; 95% CI: 0.58-0.84; P < 0.01), whereas carriers of ε4 allele were of increased risk of AD (OR = 3.62; 95% CI: 3.03-4.32; P < 0.05), compared to these of ε3 allele. Circulating TC was significantly reduced in carriers of ε2 allele (WMD = - 0.29 mmol/L; 95% CI: -0.54 to -0.03; P < 0.05) and increased in carriers of ε4 allele (WMD = 0.42 mmol/l; 95% CI: 0.001-0.84; P < 0.05). In addition, carriers of ε4 allele had reduction in circulating HDL-C (WMD = - 0.04 mmol/L; 95% CI: - 0.07 to -0.001; P < 0.05). In comparing allele ε2 with ε3, the predicted OR of having AD for 1 mg/dL increment in circulating TC was 0.97 (95% CI: 0.86-0.98; P < 0.05). Comparing allele ε4 with ε3, the predicted OR for a 1 mg/dL increment in TC was 1.08 (95% CI: 1.05-17.58; P < 0.05), and reduction in HDL-C was 2.30 (95% CI: 1.51-43.99; P < 0.05). Our findings demonstrate that high circulating TC and reduced HDL-C levels might be potential risk factors of the development of AD.
Collapse
|
23
|
APP Osaka Mutation in Familial Alzheimer's Disease-Its Discovery, Phenotypes, and Mechanism of Recessive Inheritance. Int J Mol Sci 2020; 21:ijms21041413. [PMID: 32093100 PMCID: PMC7073033 DOI: 10.3390/ijms21041413] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 02/17/2020] [Accepted: 02/17/2020] [Indexed: 12/14/2022] Open
Abstract
Alzheimer’s disease is believed to begin with synaptic dysfunction caused by soluble Aβ oligomers. When this oligomer hypothesis was proposed in 2002, there was no direct evidence that Aβ oligomers actually disrupt synaptic function to cause cognitive impairment in humans. In patient brains, both soluble and insoluble Aβ species always coexist, and therefore it is difficult to determine which pathologies are caused by Aβ oligomers and which are caused by amyloid fibrils. Thus, no validity of the oligomer hypothesis was available until the Osaka mutation was discovered. This mutation, which was found in a Japanese pedigree of familial Alzheimer’s disease, is the deletion of codon 693 of APP gene, resulting in mutant Aβ lacking the 22nd glutamate. Only homozygous carriers suffer from dementia. In vitro studies revealed that this mutation has a very unique character that accelerates Aβ oligomerization but does not form amyloid fibrils. Model mice expressing this mutation demonstrated that all pathologies of Alzheimer’s disease can be induced by Aβ oligomers alone. In this review, we describe the story behind the discovery of the Osaka mutation, summarize the mutant’s phenotypes, and propose a mechanism of its recessive inheritance.
Collapse
|
24
|
Cline EN, Bicca MA, Viola KL, Klein WL. The Amyloid-β Oligomer Hypothesis: Beginning of the Third Decade. J Alzheimers Dis 2019; 64:S567-S610. [PMID: 29843241 PMCID: PMC6004937 DOI: 10.3233/jad-179941] [Citation(s) in RCA: 543] [Impact Index Per Article: 108.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The amyloid-β oligomer (AβO) hypothesis was introduced in 1998. It proposed that the brain damage leading to Alzheimer’s disease (AD) was instigated by soluble, ligand-like AβOs. This hypothesis was based on the discovery that fibril-free synthetic preparations of AβOs were potent CNS neurotoxins that rapidly inhibited long-term potentiation and, with time, caused selective nerve cell death (Lambert et al., 1998). The mechanism was attributed to disrupted signaling involving the tyrosine-protein kinase Fyn, mediated by an unknown toxin receptor. Over 4,000 articles concerning AβOs have been published since then, including more than 400 reviews. AβOs have been shown to accumulate in an AD-dependent manner in human and animal model brain tissue and, experimentally, to impair learning and memory and instigate major facets of AD neuropathology, including tau pathology, synapse deterioration and loss, inflammation, and oxidative damage. As reviewed by Hayden and Teplow in 2013, the AβO hypothesis “has all but supplanted the amyloid cascade.” Despite the emerging understanding of the role played by AβOs in AD pathogenesis, AβOs have not yet received the clinical attention given to amyloid plaques, which have been at the core of major attempts at therapeutics and diagnostics but are no longer regarded as the most pathogenic form of Aβ. However, if the momentum of AβO research continues, particularly efforts to elucidate key aspects of structure, a clear path to a successful disease modifying therapy can be envisioned. Ensuring that lessons learned from recent, late-stage clinical failures are applied appropriately throughout therapeutic development will further enable the likelihood of a successful therapy in the near-term.
Collapse
Affiliation(s)
- Erika N Cline
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - Maíra Assunção Bicca
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - Kirsten L Viola
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| | - William L Klein
- Department of Neurobiology, Cognitive Neurology and Alzheimer's Disease Center, International Institute for Nanotechnology, and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA
| |
Collapse
|
25
|
Tong XK, Trigiani LJ, Hamel E. High cholesterol triggers white matter alterations and cognitive deficits in a mouse model of cerebrovascular disease: benefits of simvastatin. Cell Death Dis 2019; 10:89. [PMID: 30692517 PMCID: PMC6349936 DOI: 10.1038/s41419-018-1199-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 10/19/2018] [Accepted: 10/25/2018] [Indexed: 12/17/2022]
Abstract
Transgenic mice overexpressing transforming growth factor-β1 (TGF mice) display impaired cerebrovascular reactivity, cerebral hypoperfusion and neurovascular uncoupling, but no overt cognitive deficits until old age. Cardiovascular diseases are a major risk factor for vascular cognitive impairment and dementia (VCID). We investigated the impact of a high cholesterol diet (HCD) on cerebrovascular and cognitive function in adult (6 months) and aged (12 months) TGF mice, together with the potential benefit of simvastatin (SV), an anti-cholesterol drug with pleiotropic effects, in adult mice. HCD increased blood, but not brain, cholesterol levels in treated mice, which SV did not reduce. In WT mice, HCD induced small, albeit significant, impairment in endothelium-dependent dilatory function. In TGF mice, HCD worsened the established brain vessel dilatory dysfunction in an age-dependent manner and increased the number of string vessels in the white matter (WM), alterations respectively normalized and significantly countered by SV. HCD triggered cognitive decline only in TGF mice at both ages, a deficit prevented by SV. Concurrently, HCD upregulated galectin−3 immunoreactivity in WM microglial cells, a response significantly reduced in SV-treated TGF mice. Grey matter astrogliosis and microgliosis were not affected by HCD or SV. In the subventricular zone of adult HCD-treated TGF mice, SV promoted oligogenesis and migration of oligodendrocyte progenitor cells. The results demonstrate that an underlying cerebrovascular pathology increases vulnerability to cognitive failure when combined to another risk factor for dementia, and that WM alterations are associated with this loss of function. The results further indicate that myelin repair mechanisms, as triggered by SV, may bear promise in preventing or delaying cognitive decline related to VCID.
Collapse
Affiliation(s)
- Xin-Kang Tong
- Laboratory of Cerebrovascular Research, Montreal Neurological Institute, McGill University, 3801 University Street, Montréal, H3A 2B4, QC, Canada
| | - Lianne J Trigiani
- Laboratory of Cerebrovascular Research, Montreal Neurological Institute, McGill University, 3801 University Street, Montréal, H3A 2B4, QC, Canada
| | - Edith Hamel
- Laboratory of Cerebrovascular Research, Montreal Neurological Institute, McGill University, 3801 University Street, Montréal, H3A 2B4, QC, Canada.
| |
Collapse
|
26
|
Fernández-Pérez EJ, Sepúlveda FJ, Peters C, Bascuñán D, Riffo-Lepe NO, González-Sanmiguel J, Sánchez SA, Peoples RW, Vicente B, Aguayo LG. Effect of Cholesterol on Membrane Fluidity and Association of Aβ Oligomers and Subsequent Neuronal Damage: A Double-Edged Sword. Front Aging Neurosci 2018; 10:226. [PMID: 30123122 PMCID: PMC6085471 DOI: 10.3389/fnagi.2018.00226] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/03/2018] [Indexed: 02/06/2023] Open
Abstract
Background: The beta-amyloid peptide (Aβ) involved in Alzheimer's disease (AD) has been described to associate/aggregate on the cell surface disrupting the membrane through pore formation and breakage. However, molecular determinants involved for this interaction (e.g., some physicochemical properties of the cell membrane) are largely unknown. Since cholesterol is an important molecule for membrane structure and fluidity, we examined the effect of varying cholesterol content with the association and membrane perforation by Aβ in cultured hippocampal neurons. Methods: To decrease or increase the levels of cholesterol in the membrane we used methyl-β-cyclodextrin (MβCD) and MβCD/cholesterol, respectively. We analyzed if membrane fluidity was affected using generalized polarization (GP) imaging and the fluorescent dye di-4-ANEPPDHQ. Additionally membrane association and perforation was assessed using immunocytochemistry and electrophysiological techniques, respectively. Results: The results showed that cholesterol removal decreased the macroscopic association of Aβ to neuronal membranes (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.05) and induced a facilitation of the membrane perforation by Aβ with respect to control cells (half-time for maximal charge transferred: control = 7.2 vs. MβCD = 4.4). Under this condition, we found an increase in membrane fluidity (46 ± 3.3% decrease in GP value, p < 0.001). On the contrary, increasing cholesterol levels incremented membrane rigidity (38 ± 2.7% increase in GP value, p < 0.001) and enhanced the association and clustering of Aβ (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.01), but inhibited membrane disruption. Conclusion: Our results strongly support the significance of plasma membrane organization in the toxic effects of Aβ in hippocampal neurons, since fluidity can regulate distribution and insertion of the Aβ peptide in the neuronal membrane.
Collapse
Affiliation(s)
- Eduardo J Fernández-Pérez
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Fernando J Sepúlveda
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Denisse Bascuñán
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Nicolás O Riffo-Lepe
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | | | - Susana A Sánchez
- Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Robert W Peoples
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
| | - Benjamín Vicente
- Department of Psychiatry and Mental Health, Universidad de Concepción, Concepción, Chile
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| |
Collapse
|
27
|
Gupta S, Yadav K, Mantri SS, Singhal NK, Ganesh S, Sandhir R. Evidence for Compromised Insulin Signaling and Neuronal Vulnerability in Experimental Model of Sporadic Alzheimer’s Disease. Mol Neurobiol 2018; 55:8916-8935. [DOI: 10.1007/s12035-018-0985-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Accepted: 02/28/2018] [Indexed: 02/07/2023]
|
28
|
Fernández-Pérez EJ, Sepúlveda FJ, Peters C, Bascuñán D, Riffo-Lepe NO, González-Sanmiguel J, Sánchez SA, Peoples RW, Vicente B, Aguayo LG. Effect of Cholesterol on Membrane Fluidity and Association of Aβ Oligomers and Subsequent Neuronal Damage: A Double-Edged Sword. Front Aging Neurosci 2018. [PMID: 30123122 DOI: 10.3389/fnagi.2018.002.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Background: The beta-amyloid peptide (Aβ) involved in Alzheimer's disease (AD) has been described to associate/aggregate on the cell surface disrupting the membrane through pore formation and breakage. However, molecular determinants involved for this interaction (e.g., some physicochemical properties of the cell membrane) are largely unknown. Since cholesterol is an important molecule for membrane structure and fluidity, we examined the effect of varying cholesterol content with the association and membrane perforation by Aβ in cultured hippocampal neurons. Methods: To decrease or increase the levels of cholesterol in the membrane we used methyl-β-cyclodextrin (MβCD) and MβCD/cholesterol, respectively. We analyzed if membrane fluidity was affected using generalized polarization (GP) imaging and the fluorescent dye di-4-ANEPPDHQ. Additionally membrane association and perforation was assessed using immunocytochemistry and electrophysiological techniques, respectively. Results: The results showed that cholesterol removal decreased the macroscopic association of Aβ to neuronal membranes (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.05) and induced a facilitation of the membrane perforation by Aβ with respect to control cells (half-time for maximal charge transferred: control = 7.2 vs. MβCD = 4.4). Under this condition, we found an increase in membrane fluidity (46 ± 3.3% decrease in GP value, p < 0.001). On the contrary, increasing cholesterol levels incremented membrane rigidity (38 ± 2.7% increase in GP value, p < 0.001) and enhanced the association and clustering of Aβ (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.01), but inhibited membrane disruption. Conclusion: Our results strongly support the significance of plasma membrane organization in the toxic effects of Aβ in hippocampal neurons, since fluidity can regulate distribution and insertion of the Aβ peptide in the neuronal membrane.
Collapse
Affiliation(s)
- Eduardo J Fernández-Pérez
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Fernando J Sepúlveda
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Denisse Bascuñán
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Nicolás O Riffo-Lepe
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | | | - Susana A Sánchez
- Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Robert W Peoples
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
| | - Benjamín Vicente
- Department of Psychiatry and Mental Health, Universidad de Concepción, Concepción, Chile
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| |
Collapse
|
29
|
Chang XL, Tan L, Tan MS, Wang HF, Tan CC, Zhang W, Zheng ZJ, Kong LL, Wang ZX, Jiang T, Yu JT, Tan L. Association of HMGCR polymorphism with late-onset Alzheimer's disease in Han Chinese. Oncotarget 2017; 7:22746-51. [PMID: 27009838 PMCID: PMC5008397 DOI: 10.18632/oncotarget.8176] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 02/21/2016] [Indexed: 02/04/2023] Open
Abstract
The 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) acts as a potential genetic modifier for Alzheimer's disease (AD). Previous reports identified that HMGCR rs3846662 polymorphism is associated with biosynthesis of cholesterol in AD pathology. In order to assess the involvement of the HMGCR polymorphism in the risk of late-onset AD (LOAD) in northern Han Chinese, we performed a case–control study of 2334 unrelated subjects (984 cases and 1350 age- and gender-matched controls) to evaluate the genotype and allele distributions of the HMGCR rs3846662 with LOAD. The genotype distribution (GG, AG, AA) of rs3846662 was significantly different between LOAD patients and controls (P = 0.003), but the allele distribution did not reach a significant difference (P = 0.614). After adjusting for age, gender and the APOE ε4 status, the minor A allele of rs3846662 was validated as a protective factor for LOAD in dominant model (OR = 0.796, P = 0.02, 95% CI = 0.657–0.965). Interestingly, we observed rs3846662 polymorphism was only significantly associated with LOAD in APOE ε4 non-carriers (OR = 0.735, P = 0.005, 95% CI = [0.593, 0.912]). In conclusion, our study demonstrates A allele of HMGCR rs3846662 acts as a protective factor for LOAD in northern Han Chinese.
Collapse
Affiliation(s)
- Xiao-Long Chang
- Department of Neurology, Qingdao Municipal Hospital, Dalian Medical University, Qingdao, PR China
| | - Lin Tan
- College of Medicine and Pharmaceutics, Ocean University of China, Qingdao, PR China
| | - Meng-Shan Tan
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China
| | - Hui-Fu Wang
- Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Qingdao, PR China
| | - Chen-Chen Tan
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China
| | - Wei Zhang
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China
| | - Zhan-Jie Zheng
- Department of Geriatric, Qingdao Mental Health Center, Qingdao, PR China
| | - Ling-Li Kong
- Department of Geriatric, Qingdao Mental Health Center, Qingdao, PR China
| | - Zi-Xuan Wang
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China
| | - Teng Jiang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, PR China
| | - Jin-Tai Yu
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, Dalian Medical University, Qingdao, PR China.,College of Medicine and Pharmaceutics, Ocean University of China, Qingdao, PR China.,Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, PR China
| |
Collapse
|
30
|
Beneficial effects of TQRF and TQ nano- and conventional emulsions on memory deficit, lipid peroxidation, total antioxidant status, antioxidants genes expression and soluble Aβ levels in high fat-cholesterol diet-induced rats. Chem Biol Interact 2017; 275:61-73. [DOI: 10.1016/j.cbi.2017.07.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Revised: 06/14/2017] [Accepted: 07/17/2017] [Indexed: 01/20/2023]
|
31
|
Camponova P, Le Page A, Berrougui H, Lamoureux J, Pawelec G, Witkowski MJ, Fulop T, Khalil A. Alteration of high-density lipoprotein functionality in Alzheimer’s disease patients. Can J Physiol Pharmacol 2017; 95:894-903. [DOI: 10.1139/cjpp-2016-0710] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aims of the present study were to determine whether high-density lipoprotein (HDL) functionality-mediated cholesterol efflux is altered in Alzheimer’s disease and to investigate the role and effect of amyloid-beta (Aβ) in the regulation of the anti-atherogenic activity of HDL. Eighty-seven elderly subjects were recruited, of whom 27 were healthy, 27 had mild cognitive impairment (MCI), and 33 had mild Alzheimer’s disease (mAD). Our results showed that total cholesterol levels are negatively correlated with the Mini-Mental State Examination (MMSE) score (r = –0.2602, p = 0.0182). HDL from the mAD patients was less efficient at mediating cholesterol efflux from J774 macrophages (p < 0.05) than HDL from the healthy subjects and MCI patients. While HDL from the MCI patients was also less efficient at mediating cholesterol efflux than HDL from the healthy subjects, the difference was not significant. Interestingly, the difference between the healthy subjects and the MCI and mAD patients with respect to the capacity of HDL to mediate cholesterol efflux disappeared when ATP-binding cassette transporter A1 (ABCA1)-enriched J774 macrophages were used. HDL fluidity was significantly inversely correlated with the MMSE scores (r = –0.4137, p < 0.009). In vitro measurements of cholesterol efflux using J774 macrophages showed that neither Aβ1-40nor Aβ1-42stimulate cholesterol efflux from unenriched J774 macrophages in basal or ABCA1-enriched J774 macrophages.
Collapse
Affiliation(s)
- Paméla Camponova
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
| | - Aurélie Le Page
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
| | - Hicham Berrougui
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
- Department of Biology, University Sultan Moulay Slimane, Beni Mellal, Morocco
| | - Julie Lamoureux
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
| | - Graham Pawelec
- Department of Internal Medicine II, Center for Medical Research, University of Tübingen, Tübingen, Germany
| | - M. Jacek Witkowski
- Department of Pathophysiology, Medical University of Gdańsk, Gdańsk, Poland
| | - Tamas Fulop
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
| | - Abdelouahed Khalil
- Department of Medicine, Geriatrics Service, Faculty of Medicine and Biological Sciences, University of Sherbrooke, Sherbrooke, QC J1H 4N4, Canada
| |
Collapse
|
32
|
Xia H, Wu L, Chu M, Feng H, Lu C, Wang Q, He M, Ge X. Effects of breviscapine on amyloid beta 1-42 induced Alzheimer's disease mice: A HPLC-QTOF-MS based plasma metabonomics study. J Chromatogr B Analyt Technol Biomed Life Sci 2017; 1057:92-100. [PMID: 28511119 DOI: 10.1016/j.jchromb.2017.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Revised: 05/02/2017] [Accepted: 05/06/2017] [Indexed: 12/19/2022]
Abstract
Herba Erigerontis has long been used to cure apoplexy hemiplegia and precordial pain in China. In addition, the bioactivities of its total flavonoids-breviscapine included inhibiting amyloid beta (Aβ) fibril formation, antioxidation and metal chelating, which are beneficial to treat Alzheimer's disease (AD). Hence, A HPLC-QTOF-MS based plasma metabonomics approach was applied to investigate the neuroprotective effects of breviscapine on intracerebroventricular injection of aggregated Aβ 1-42 induced AD mice for the first time in the study. Ten potential biomarkers were screened out by multivariate statistical analysis, eight of which were further identified as indoleacrylic acid, C16 sphinganine, LPE (22:6), sulfolithocholic acid, LPC (16:0), PA (22:1/0:0), taurodeoxycholic acid, and PC (0:0/18:0). According to their metabolic pathways, it was supposed that breviscapine ameliorated the learning and memory deficits of AD mice predominantly by regulating phospholipids metabolism, elevating serotonin level and lowering cholesterols content in vivo.
Collapse
Affiliation(s)
- Hongjun Xia
- Medical College, Yangzhou University, 11 Huaihai Road, Yangzhou, 225001, Jiangsu, People's Republic of China.
| | - Lingling Wu
- Medical College, Yangzhou University, 11 Huaihai Road, Yangzhou, 225001, Jiangsu, People's Republic of China
| | - Mengying Chu
- Medical College, Yangzhou University, 11 Huaihai Road, Yangzhou, 225001, Jiangsu, People's Republic of China
| | - Huimin Feng
- Medical College, Yangzhou University, 11 Huaihai Road, Yangzhou, 225001, Jiangsu, People's Republic of China
| | - Chunliang Lu
- Testing Center, Yangzhou University, 48 East Wenhui Road, Yangzhou, 225009, Jiangsu, People's Republic of China
| | - Qinghe Wang
- Bruker Corporation, 418 Guiping Road, Shanghai, 200233, People's Republic of China
| | - Minghai He
- Bruker Corporation, 418 Guiping Road, Shanghai, 200233, People's Republic of China
| | - Xiaoqun Ge
- Medical College, Yangzhou University, 11 Huaihai Road, Yangzhou, 225001, Jiangsu, People's Republic of China
| |
Collapse
|
33
|
Zhao XS, Wu Q, Peng J, Pan LH, Ren Z, Liu HT, Jiang ZS, Wang GX, Tang ZH, Liu LS. Hyperlipidemia-induced apoptosis of hippocampal neurons in apoE(-/-) mice may be associated with increased PCSK9 expression. Mol Med Rep 2016; 15:712-718. [PMID: 28000893 PMCID: PMC5364825 DOI: 10.3892/mmr.2016.6055] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 09/27/2016] [Indexed: 02/02/2023] Open
Abstract
Hyperlipidemia is a risk factor for Alzheimer's disease (AD) and other neurodegenerative diseases. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a lipid regulatory gene involved in cell apoptosis. However, the function and mechanism of PCSK9 in neuronal apoptosis following hyperlipidemia remains to be elucidated. The present study established a hyperlipidemic mouse model by feeding a high-fat diet (HFD) to 6-week-old apoE(−/−) mice. Plasma lipid levels, hippocampal lipid accumulation, hippocampal histology, and hippocampal neuronal apoptosis were all monitored for changes. The expression levels of PCSK9, β-secretase 1 (BACE1), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and caspase-3 in hippocampal CA3 and CA1 neurons were also measured. Results demonstrated that a HFD increased the lipid accumulation in the CA3 hippocampus and the levels of plasma lipids, including triglycerides, total cholesterol, low-density lipoprotein, and high-density lipoprotein. In addition, CA3 neurons in the HFD group indicated apparent injuries and increased neuronal apoptosis, which are associated with the expression of Bcl-2, Bax, and caspase-3. A HFD also increased the expression levels of PCSK9 and BACE1. BACE1 promotes cleavage of amyloid precursor proteins to generate β-amyloid peptide (Aβ), which induces neuronal apoptosis. Protein levels of Aβ are associated with the observation of amyloid plaques in the hippocampus of the HFD group. The results suggest that hyperlipidemia regulates neuronal apoptosis by increasing PCSK9 and BACE1 expression. Overall, the current study may elucidate the role of lipid metabolism disorder in AD pathogenesis.
Collapse
Affiliation(s)
- Xue-Shan Zhao
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Qi Wu
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Juan Peng
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Li-Hong Pan
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Zhong Ren
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Hui-Ting Liu
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Zhi-Sheng Jiang
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Gui-Xue Wang
- College of Bioengineering, Chongqing University, Chongqing 400030, P.R. China
| | - Zhi-Han Tang
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| | - Lu-Shan Liu
- Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan University of South China, Hengyang, Hunan 421001, P.R. China
| |
Collapse
|
34
|
Shuang R, Rui X, Wenfang L. Phytosterols and Dementia. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 2016; 71:347-354. [PMID: 27663717 DOI: 10.1007/s11130-016-0574-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
As the aging of the world's population is becoming increasingly serious, dementia-related diseases have become a hot topic in public health research. In recent years, human epidemiological studies have focused on lipid metabolism disorders and dementia. The efficacy of phytosterol intake as a cholesterol-lowering agent has been demonstrated. Phytosterols directly serve as ligands of the nuclear receptors, peroxisome proliferator-activated receptors (PPARs), activating Sirtuin 1 (SIRT-1), which are involved in the regulation of lipid metabolism and the pathogenesis of dementia. Moreover, phytosterols mediate cell and membrane cholesterol efflux or beta amyloid (Aβ) metabolism, which have preventative and therapeutic effects on dementia. Additionally, incorporation of plant sterols in lipid rafts can effectively reduce dietary fat and alter the dietary composition of fiber, fat and cholesterol to regulate appetite and calories. Overall, the objectives of this review are to explore whether phytosterols are a potentially effective target for the prevention of dementia and to discuss a possible molecular mechanism by which phytosterols play a role in the pathogenesis of dementia via the PPARs-SIRT-1 pathway.
Collapse
Affiliation(s)
- Rong Shuang
- Department of Public Health School, Wuhan University of Science & Technology, Wuhan, 430065, China.
| | - Xu Rui
- Department of Public Health School, Wuhan University of Science & Technology, Wuhan, 430065, China
| | - Li Wenfang
- Department of Public Health School, Wuhan University of Science & Technology, Wuhan, 430065, China.
| |
Collapse
|
35
|
Imbalanced cholesterol metabolism in Alzheimer's disease. Clin Chim Acta 2016; 456:107-114. [DOI: 10.1016/j.cca.2016.02.024] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Revised: 02/28/2016] [Accepted: 02/28/2016] [Indexed: 11/20/2022]
|
36
|
Herms J, Dorostkar MM. Dendritic Spine Pathology in Neurodegenerative Diseases. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2016; 11:221-50. [PMID: 26907528 DOI: 10.1146/annurev-pathol-012615-044216] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Substantial progress has been made toward understanding the neuropathology, genetic origins, and epidemiology of neurodegenerative diseases, including Alzheimer's disease; tauopathies, such as frontotemporal dementia; α-synucleinopathies, such as Parkinson's disease or dementia with Lewy bodies; Huntington's disease; and amyotrophic lateral sclerosis with dementia, as well as prion diseases. Recent evidence has implicated dendritic spine dysfunction as an important substrate of the pathogenesis of dementia in these disorders. Dendritic spines are specialized structures, extending from the neuronal processes, on which excitatory synaptic contacts are formed, and the loss of dendritic spines correlates with the loss of synaptic function. We review the literature that has implicated direct or indirect structural alterations at dendritic spines in the pathogenesis of major neurodegenerative diseases, focusing on those that lead to dementias such as Alzheimer's, Parkinson's, and Huntington's diseases, as well as frontotemporal dementia and prion diseases. We stress the importance of in vivo studies in animal models.
Collapse
Affiliation(s)
- Jochen Herms
- Center for Neuropathology and Prion Research, Ludwig Maximilian University, 81377 Munich, Germany; .,Munich Cluster for Systems Neurology, Ludwig Maximilian University, 81377 Munich, Germany.,German Center for Neurodegenerative Diseases, 81377 Munich, Germany
| | - Mario M Dorostkar
- Center for Neuropathology and Prion Research, Ludwig Maximilian University, 81377 Munich, Germany;
| |
Collapse
|
37
|
Stress-induced upregulation of VLDL receptor alters Wnt-signaling in neurons. Exp Cell Res 2016; 340:238-47. [PMID: 26751967 DOI: 10.1016/j.yexcr.2016.01.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 12/16/2015] [Accepted: 01/01/2016] [Indexed: 12/12/2022]
Abstract
Lipoprotein receptor family members hold multiple roles in the brain, and alterations in lipoprotein receptor expression and function are implicated in neuronal stress, developmental disorders and neurodegenerative diseases, such as Alzheimer's disease. Berberine (BBR), a nutraceutical shown to have both neuroprotective and neurotoxic properties, is suggested to regulate lipoprotein receptor expression. We show that subtoxic concentration of BBR regulates neuronal lipoprotein receptor expression in a receptor- and time-dependent fashion in cerebellar granule neurons (CGN). Similarly to BBR, subtoxic concentrations of neuronal stressors cobalt chloride, thapsigargin and rotenone increased very-low-density lipoprotein receptor (VLDLR) mRNA and protein expression in CGN suggesting a conserved pathway for stress-induced upregulation of VLDLR in neurons. We also show that VLDLR upregulation is accompanied by transiently increased stabilization of hypoxia-induced factor 1 alpha (HIF-1α) and decreased β-catenin levels affecting the Wnt pathway through GSK3β phosphorylation, a crucial player in neurodegenerative processes. Our results indicate that neuronal stress differentially regulates lipoprotein receptor expression in neurons, with VLDLR upregulation as a common element as a modulator of neuronal Wnt signaling.
Collapse
|
38
|
Chen JH, Hsieh CJ, Huang YL, Chen YC, Chen TF, Sun Y, Wen LL, Yip PK, Chu YM. Genetic polymorphisms of lipid metabolism gene SAR1 homolog B and the risk of Alzheimer's disease and vascular dementia. J Formos Med Assoc 2016; 115:38-44. [DOI: 10.1016/j.jfma.2015.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/02/2014] [Accepted: 01/14/2015] [Indexed: 01/08/2023] Open
|
39
|
Chen YL, Wang LM, Chen Y, Gao JY, Marshall C, Cai ZY, Hu G, Xiao M. Changes in astrocyte functional markers and β-amyloid metabolism-related proteins in the early stages of hypercholesterolemia. Neuroscience 2015; 316:178-91. [PMID: 26724580 DOI: 10.1016/j.neuroscience.2015.12.039] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 12/11/2015] [Accepted: 12/19/2015] [Indexed: 12/21/2022]
Abstract
Cholesterol is an essential substance for maintaining normal structure and function of the brain. But unfortunately, a long-term high-cholesterol diet can lead to a variety of pathological changes of the brain such as β-amyloid (Aβ) accumulation, Tau hyperphosphorylation, reactive gliosis, neuroinflammation, neuronal death and synaptic degeneration. These pathological changes have complex internal relations with one other, causing memory impairment and participating in the pathogenesis of Alzheimer's disease (AD). However, early hypercholesterolemia-induced events that lead to brain deterioration are not clear. To address this, 6-month-old female mice were fed a 3% cholesterol diet for 8weeks, followed by behavioral, biochemical and neuropathological analyses. The high-cholesterol-fed mice did not show neuronal and synaptic impairment or cognitive deficits compared with mice given a normal diet, but astrocytes were mildly activated with increased expression of functional markers including apolipoprotein E and aquaporin 4 in the hippocampus. Hippocampal interleukin-1β expression slightly increased, but interleukin-6 (IL-6) and tumor necrosis factor-α did not change significantly compared with those in the control group. Levels of Aβ, and its precursor protein, were unaffected, but levels of presenilin 1 and insulin-degrading enzyme (IDE), that initiate Aβ generation and degradation, respectively, increased in the hippocampus of the model mice. In addition, Tau phosphorylation levels were not different between the control and model groups. These results suggest that changes in astrocyte functional markers and Aβ metabolism proteins, which contribute to maintaining brain cholesterol and Aβ homeostasis, are early events in the process of hypercholesterolemia-related neuropathological changes.
Collapse
Affiliation(s)
- Y L Chen
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China
| | - L M Wang
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China
| | - Y Chen
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China
| | - J Y Gao
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China
| | - C Marshall
- Department of Rehabilitation Sciences, University of Kentucky Center of Excellence in Rural Health, Hazard, KY, USA
| | - Z Y Cai
- Department of Neurology, Shiyan Renmin Hospital, Hubei University of Medicine, No 39 Chaoyang Middle Road, Shiyan, Hubei Province 442000, People's Republic of China
| | - G Hu
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China
| | - M Xiao
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China.
| |
Collapse
|
40
|
Foley AM, Ammar ZM, Lee RH, Mitchell CS. Systematic review of the relationship between amyloid-β levels and measures of transgenic mouse cognitive deficit in Alzheimer's disease. J Alzheimers Dis 2015; 44:787-95. [PMID: 25362040 PMCID: PMC4346318 DOI: 10.3233/jad-142208] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Amyloid-β (Aβ) is believed to directly affect memory and learning in Alzheimer’s disease (AD). It is widely suggested that there is a relationship between Aβ40 and Aβ42 levels and cognitive performance. In order to explore the validity of this relationship, we performed a meta-analysis of 40 peer-reviewed, published AD transgenic mouse studies that quantitatively measured Aβ levels in brain tissue after assessing cognitive performance. We examined the relationship between Aβ levels (Aβ40, Aβ42, or the ratio of Aβ42 to Aβ40) and cognitive function as measured by escape latency times in the Morris water maze or exploratory preference percentage in the novel object recognition test. Our systematic review examined five mouse models (Tg2576, APP, PS1, 3xTg, APP(OSK)-Tg), gender, and age. The overall result revealed no statistically significant correlation between quantified Aβ levels and experimental measures of cognitive function. However, enough of the trends were of the same sign to suggest that there probably is a very weak qualitative trend visible only across many orders of magnitude. In summary, the results of the systematic review revealed that mice bred to show elevated levels of Aβ do not perform significantly worse in cognitive tests than mice that do not have elevated Aβ levels. Our results suggest two lines of inquiry: 1) Aβ is a biochemical “side effect” of the AD pathology; or 2) learning and memory deficits in AD are tied to the presence of qualitatively “high” levels of Aβ but are not quantitatively sensitive to the levels themselves.
Collapse
Affiliation(s)
- Avery M Foley
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Zeena M Ammar
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Robert H Lee
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Cassie S Mitchell
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| |
Collapse
|
41
|
La Marca V, Maresca B, Spagnuolo MS, Cigliano L, Dal Piaz F, Di Iorio G, Abrescia P. Lecithin-cholesterol acyltransferase in brain: Does oxidative stress influence the 24-hydroxycholesterol esterification? Neurosci Res 2015; 105:19-27. [PMID: 26454063 DOI: 10.1016/j.neures.2015.09.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 09/04/2015] [Accepted: 09/28/2015] [Indexed: 01/27/2023]
Abstract
24-Hydroxycholesterol (24OH-C) is esterified by the enzyme lecithin-cholesterol acyltransferase (LCAT) in the cerebrospinal fluid (CSF). We report here that the level of 24OH-C esters was lower in CSF of patients with amyotrophic lateral sclerosis than in healthy subjects (54% vs 68% of total 24OH-C, p=0.0005; n=8). Similarly, the level of 24OH-C esters in plasma was lower in patients than in controls (62% vs 77% of total 24OH-C; p=0.0076). The enzyme amount in CSF, as measured by densitometry of the protein band revealed by immunoblotting, was about 4-fold higher in patients than in controls (p=0.0085). As differences in the concentration of the LCAT stimulator Apolipoprotein E were not found, we hypothesized that the reduced 24OH-C esterification in CSF of patients might depend on oxidative stress. We actually found that oxidative stress reduced LCAT activity in vitro, and 24OH-C effectively stimulated the enzyme secretion from astrocytoma cells in culture. Enhanced LCAT secretion from astrocytes might represent an adaptive response to the increase of non-esterified 24OH-C percentage, aimed to avoid the accumulation of this neurotoxic compound. The low degree of 24OH-C esterification in CSF or plasma might reflect reduced activity of LCAT during neurodegeneration.
Collapse
Affiliation(s)
- Valeria La Marca
- Dipartimento di Biologia, Università di Napoli Federico II, via Mezzocannone 8, 80134 Napoli, Italy.
| | - Bernardetta Maresca
- Dipartimento di Biologia, Università di Napoli Federico II, via Mezzocannone 8, 80134 Napoli, Italy.
| | - Maria Stefania Spagnuolo
- Istituto per il Sistema Produzione Animale in Ambiente Mediterraneo (ISPAAM), Consiglio Nazionale delle Ricerche, via Argine 1085, 80147 Napoli, Italy.
| | - Luisa Cigliano
- Dipartimento di Biologia, Università di Napoli Federico II, via Cinthia 4, 80126 Napoli, Italy; Centro Interuniversitario di Ricerca sui Peptidi Bioattivi (CIRPEB), via Mezzocannone 16, 80134 Napoli, Italy.
| | - Fabrizio Dal Piaz
- Dipartimento di Farmacia, Università di Salerno, via Giovanni Paolo II 132, 84084 Fisciano, Italy.
| | - Giuseppe Di Iorio
- Dipartimento di Scienze Mediche, Chirurgiche, Neurologiche, Metaboliche e dell'Invecchiamento, Seconda Università di Napoli, Piazza Miraglia 2, 80138 Napoli, Italy.
| | - Paolo Abrescia
- Dipartimento di Biologia, Università di Napoli Federico II, via Mezzocannone 8, 80134 Napoli, Italy; Centro Interuniversitario di Ricerca sui Peptidi Bioattivi (CIRPEB), via Mezzocannone 16, 80134 Napoli, Italy.
| |
Collapse
|
42
|
Chakrabarti S, Khemka VK, Banerjee A, Chatterjee G, Ganguly A, Biswas A. Metabolic Risk Factors of Sporadic Alzheimer's Disease: Implications in the Pathology, Pathogenesis and Treatment. Aging Dis 2015; 6:282-99. [PMID: 26236550 DOI: 10.14336/ad.2014.002] [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] [Received: 07/30/2013] [Revised: 09/30/2014] [Accepted: 10/02/2014] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD), the major cause of dementia among the elderly world-wide, manifests in familial and sporadic forms, and the latter variety accounts for the majority of the patients affected by this disease. The etiopathogenesis of sporadic AD is complex and uncertain. The autopsy studies of AD brain have provided limited understanding of the antemortem pathogenesis of the disease. Experimental AD research with transgenic animal or various cell based models has so far failed to explain the complex and varied spectrum of AD dementia. The review, therefore, emphasizes the importance of AD related risk factors, especially those with metabolic implications, identified from various epidemiological studies, in providing clues to the pathogenesis of this complex disorder. Several metabolic risk factors of AD like hypercholesterolemia, hyperhomocysteinemia and type 2 diabetes have been studied extensively both in epidemiology and experimental research, while much less is known about the role of adipokines, pro-inflammatory cytokines and vitamin D in this context. Moreover, the results from many of these studies have shown a degree of variability which has hindered our understanding of the role of AD related risk factors in the disease progression. The review also encompasses the recent recommendations regarding clinical and neuropathological diagnosis of AD and brings out the inherent uncertainty and ambiguity in this area which may have a distinct impact on the outcome of various population-based studies on AD-related risk factors.
Collapse
Affiliation(s)
- Sasanka Chakrabarti
- Department of Biochemistry, Institute of Post Graduate Medical Education and Research, Kolkata, India
| | - Vineet Kumar Khemka
- Department of Biochemistry, Institute of Post Graduate Medical Education and Research, Kolkata, India
| | - Anindita Banerjee
- Department of Biochemistry, Institute of Post Graduate Medical Education and Research, Kolkata, India. ; Department of Biochemistry, ICARE Institute of Medical Sciences and Research, Haldia, India
| | - Gargi Chatterjee
- Department of Biochemistry, Institute of Post Graduate Medical Education and Research, Kolkata, India
| | - Anirban Ganguly
- Department of Biochemistry, Institute of Post Graduate Medical Education and Research, Kolkata, India
| | - Atanu Biswas
- Department of Neuromedicine, Bangur Institute of Neurosciences (BIN), Kolkata, India
| |
Collapse
|
43
|
Hohsfield LA, Daschil N, Orädd G, Strömberg I, Humpel C. Vascular pathology of 20-month-old hypercholesterolemia mice in comparison to triple-transgenic and APPSwDI Alzheimer's disease mouse models. Mol Cell Neurosci 2015; 63:83-95. [PMID: 25447943 DOI: 10.1016/j.mcn.2014.10.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/02/2014] [Accepted: 10/27/2014] [Indexed: 10/24/2022] Open
Abstract
Several studies have shown that elevated plasma cholesterol levels (i.e. hypercholesterolemia) serve as a risk factor for late-onset Alzheimer's disease (AD). However, it remains unclear how hypercholesterolemia may contribute to the onset and progression of AD pathology. In order to determine the role of hypercholesterolemia at various stages of AD, we evaluated the effects of high cholesterol diet (5% cholesterol) in wild-type (WT; C57BL6) and triple-transgenic AD (3xTg-AD; Psen1, APPSwe, tauB301L) mice at 7, 14, and 20 months. The transgenic APP-Swedish/Dutch/Iowa AD mouse model (APPSwDI) was used as a control since these animals are more pathologically-accelerated and are known to exhibit extensive plaque deposition and cerebral amyloid angiopathy. Here, we describe the effects of high cholesterol diet on: (1) cognitive function and stress, (2) AD-associated pathologies, (3) neuroinflammation, (4) blood–brain barrier disruption and ventricle size, and (5) vascular dysfunction. Our data show that high dietary cholesterol increases weight, slightly impairs cognitive function, promotes glial cell activation and complement-related pathways, enhances the infiltration of blood-derived proteins and alters vascular integrity, however, it does not induce AD-related pathologies. While normal-fed 3xTg-AD mice display a typical AD-like pathology in addition to severe cognitive impairment and neuroinflammation at 20 months of age, vascular alterations are less pronounced. No microbleedings were seen by MRI, however, the ventricle size was enlarged. Triple-transgenic AD mice, on the other hand, fed a high cholesterol diet do not survive past 14 months of age. Our data indicates that cholesterol does not markedly potentiate AD-related pathology, nor does it cause significant impairments in cognition. However, it appears that high cholesterol diet markedly increases stress-related plasma corticosterone levels as well as some vessel pathologies. Together, our findings represent the first demonstration of prolonged high cholesterol diet and the examination of its effects at various stages of cerebrovascular- and AD-related disease.
Collapse
|
44
|
Dorostkar MM, Zou C, Blazquez-Llorca L, Herms J. Analyzing dendritic spine pathology in Alzheimer's disease: problems and opportunities. Acta Neuropathol 2015; 130:1-19. [PMID: 26063233 PMCID: PMC4469300 DOI: 10.1007/s00401-015-1449-5] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 06/02/2015] [Accepted: 06/02/2015] [Indexed: 12/22/2022]
Abstract
Synaptic failure is an immediate cause of cognitive decline and memory dysfunction in Alzheimer’s disease. Dendritic spines are specialized structures on neuronal processes, on which excitatory synaptic contacts take place and the loss of dendritic spines directly correlates with the loss of synaptic function. Dendritic spines are readily accessible for both in vitro and in vivo experiments and have, therefore, been studied in great detail in Alzheimer’s disease mouse models. To date, a large number of different mechanisms have been proposed to cause dendritic spine dysfunction and loss in Alzheimer’s disease. For instance, amyloid beta fibrils, diffusible oligomers or the intracellular accumulation of amyloid beta have been found to alter the function and structure of dendritic spines by distinct mechanisms. Furthermore, tau hyperphosphorylation and microglia activation, which are thought to be consequences of amyloidosis in Alzheimer’s disease, may also contribute to spine loss. Lastly, genetic and therapeutic interventions employed to model the disease and elucidate its pathogenetic mechanisms in experimental animals may cause alterations of dendritic spines on their own. However, to date none of these mechanisms have been translated into successful therapeutic approaches for the human disease. Here, we critically review the most intensely studied mechanisms of spine loss in Alzheimer’s disease as well as the possible pitfalls inherent in the animal models of such a complex neurodegenerative disorder.
Collapse
Affiliation(s)
- Mario M. Dorostkar
- />Ludwig-Maximilians University Munich, Center for Neuropathology and Prion Research, Feodor-Lynen-Str. 23, 81377 Munich, Germany
| | - Chengyu Zou
- />Ludwig-Maximilians University Munich, Center for Neuropathology and Prion Research, Feodor-Lynen-Str. 23, 81377 Munich, Germany
- />Graduate School of Systemic Neuroscience, Ludwig-Maximilians-University Munich, Munich, Germany
- />German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen-Str. 23, 81377 Munich, Germany
| | - Lidia Blazquez-Llorca
- />Ludwig-Maximilians University Munich, Center for Neuropathology and Prion Research, Feodor-Lynen-Str. 23, 81377 Munich, Germany
- />German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen-Str. 23, 81377 Munich, Germany
| | - Jochen Herms
- />German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen-Str. 23, 81377 Munich, Germany
- />Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
| |
Collapse
|
45
|
A high-cholesterol diet enriched with polyphenols from Oriental plums (Prunus salicina) improves cognitive function and lowers brain cholesterol levels and neurodegenerative-related protein expression in mice. Br J Nutr 2015; 113:1550-7. [DOI: 10.1017/s0007114515000732] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Ageing accompanied by a decline in cognitive performance may be a result of the long-term effects of oxidative stress on neurologic processes. It has been shown that high-cholesterol contents in the blood and brain may lead to the deposition of the β-amyloid (Aβ) protein in the brain, which damages brain cells. The present study was designed to observe the effect of polyphenol-rich Oriental plums on cognitive function and cerebral neurodegeneration-related protein expression in mice that were fed a high-cholesterol diet for 5 months. The study consisted of four groups: the control (Ctrl) group, which was fed the American Institute of Nutrition (AIN)-93M diet; the high cholesterol (HC) group, which was fed the AIN-93M diet with 5 % cholesterol; the high cholesterol+low Oriental plum (LOP) group, which was fed the AIN-93M diet with 5 % cholesterol and 2 % Oriental plum powder; and the high cholesterol+high Oriental plum (HOP) group, which was fed the AIN-93M diet with 5 % cholesterol and 5 % Oriental plum powder. Measurements of cognitive function were assessed using the Morris water maze, and the mRNA expression of cholesterol hydroxylase (Cyp46), Aβ and β-secretase 1 (BACE1) were analysed. The results showed that cholesterol concentrations in both the blood and the brain were significantly higher in the HC group than in the Ctrl and HOP groups at the end of the trial. The high-cholesterol diet per se produced significant cognitive deficits, which were accompanied by a significantly increased mRNA expression of Cyp46, BACE1, Aβ and 24-hydroxycholesterol in the brain cortex and hippocampus. However, all of these variables were non-significantly increased in the HOP group as compared to the Ctrl group. In conclusion, incorporating polyphenol-enriched Oriental plum into a high-cholesterol diet can ameliorate some of the symptoms of neurodegenerative conditions.
Collapse
|
46
|
Viola KL, Klein WL. Amyloid β oligomers in Alzheimer's disease pathogenesis, treatment, and diagnosis. Acta Neuropathol 2015; 129:183-206. [PMID: 25604547 DOI: 10.1007/s00401-015-1386-3] [Citation(s) in RCA: 440] [Impact Index Per Article: 48.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 01/11/2015] [Accepted: 01/11/2015] [Indexed: 12/22/2022]
Abstract
Protein aggregation is common to dozens of diseases including prionoses, diabetes, Parkinson's and Alzheimer's. Over the past 15 years, there has been a paradigm shift in understanding the structural basis for these proteinopathies. Precedent for this shift has come from investigation of soluble Aβ oligomers (AβOs), toxins now widely regarded as instigating neuron damage leading to Alzheimer's dementia. Toxic AβOs accumulate in AD brain and constitute long-lived alternatives to the disease-defining Aβ fibrils deposited in amyloid plaques. Key experiments using fibril-free AβO solutions demonstrated that while Aβ is essential for memory loss, the fibrillar Aβ in amyloid deposits is not the agent. The AD-like cellular pathologies induced by AβOs suggest their impact provides a unifying mechanism for AD pathogenesis, explaining why early stage disease is specific for memory and accounting for major facets of AD neuropathology. Alternative ideas for triggering mechanisms are being actively investigated. Some research favors insertion of AβOs into membrane, while other evidence supports ligand-like accumulation at particular synapses. Over a dozen candidate toxin receptors have been proposed. AβO binding triggers a redistribution of critical synaptic proteins and induces hyperactivity in metabotropic and ionotropic glutamate receptors. This leads to Ca(2+) overload and instigates major facets of AD neuropathology, including tau hyperphosphorylation, insulin resistance, oxidative stress, and synapse loss. Because different species of AβOs have been identified, a remaining question is which oligomer is the major pathogenic culprit. The possibility has been raised that more than one species plays a role. Despite some key unknowns, the clinical relevance of AβOs has been established, and new studies are beginning to point to co-morbidities such as diabetes and hypercholesterolemia as etiological factors. Because pathogenic AβOs appear early in the disease, they offer appealing targets for therapeutics and diagnostics. Promising therapeutic strategies include use of CNS insulin signaling enhancers to protect against the presence of toxins and elimination of the toxins through use of highly specific AβO antibodies. An AD-dependent accumulation of AβOs in CSF suggests their potential use as biomarkers and new AβO probes are opening the door to brain imaging. Overall, current evidence indicates that Aβ oligomers provide a substantive molecular basis for the cause, treatment and diagnosis of Alzheimer's disease.
Collapse
|
47
|
Hamed SA. Atherosclerosis in epilepsy: its causes and implications. Epilepsy Behav 2014; 41:290-6. [PMID: 25164495 DOI: 10.1016/j.yebeh.2014.07.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 07/03/2014] [Accepted: 07/04/2014] [Indexed: 12/22/2022]
Abstract
Evidence from epidemiological, longitudinal, prospective, double-blinded clinical trials as well as case reports documents age-accelerated atherosclerosis with increased carotid artery intima media thickness (CA-IMT) in patients with epilepsy. These findings raise concern regarding their implications for age-accelerated cognitive and behavioral changes in midlife and risk of later age-related cognitive disorders including neurodegenerative processes such as Alzheimer's disease (AD). Chronic epilepsy, cerebral atherosclerosis, and age-related cognitive disorders including AD share many clinical manifestations (e.g. characteristic cognitive deficits), risk factors, and structural and pathological brain abnormalities. These shared risk factors include increased CA-IMT, hyperhomocysteinemia (HHcy), lipid abnormalities, weight gain and obesity, insulin resistance (IR), and high levels of inflammatory and oxidative stresses. The resulting brain structural and pathological abnormalities include decreased volume of the hippocampus, increased cortical thinning of the frontal lobe, ventricular expansion and increased white matter ischemic disease, total brain atrophy, and β-amyloid protein deposition in the brain. The knowledge that age-accelerated atherosclerosis may contribute to age-accelerated cognitive and behavioral abnormalities and structural brain pathologies in patients with chronic epilepsy represents an important research path to pursue future clinical and management considerations.
Collapse
Affiliation(s)
- Sherifa A Hamed
- Department of Neurology and Psychiatry, Assiut University Hospital, Assiut, Egypt.
| |
Collapse
|
48
|
Sripetchwandee J, Pipatpiboon N, Pratchayasakul W, Chattipakorn N, Chattipakorn SC. DPP-4 Inhibitor and PPARγ Agonist Restore the Loss of CA1 Dendritic Spines in Obese Insulin-resistant Rats. Arch Med Res 2014; 45:547-52. [DOI: 10.1016/j.arcmed.2014.09.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 09/12/2014] [Indexed: 02/07/2023]
|
49
|
Tang TC, Hu Y, Kienlen-Campard P, El Haylani L, Decock M, Van Hees J, Fu Z, Octave JN, Constantinescu SN, Smith SO. Conformational changes induced by the A21G Flemish mutation in the amyloid precursor protein lead to increased Aβ production. Structure 2014; 22:387-96. [PMID: 24462250 DOI: 10.1016/j.str.2013.12.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 12/11/2013] [Accepted: 12/12/2013] [Indexed: 01/11/2023]
Abstract
Proteolysis of the β C-terminal fragment (β-CTF) of the amyloid precursor protein generates the Aβ peptides associated with Alzheimer's disease. Familial mutations in the β-CTF, such as the A21G Flemish mutation, can increase Aβ secretion. We establish how the Flemish mutation alters the structure of C55, the first 55 residues of the β-CTF, using FTIR and solid-state NMR spectroscopy. We show that the A21G mutation reduces β sheet structure of C55 from Leu17 to Ala21, an inhibitory region near the site of the mutation, and increases α-helical structure from Gly25 to Gly29, in a region near the membrane surface and thought to interact with cholesterol. Cholesterol also increases Aβ peptide secretion, and we show that the incorporation of cholesterol into model membranes enhances the structural changes induced by the Flemish mutant, suggesting a common link between familial mutations and the cellular environment.
Collapse
Affiliation(s)
- Tzu-Chun Tang
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Yi Hu
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | | | - Laetitia El Haylani
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Marie Decock
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Joanne Van Hees
- Ludwig Institute for Cancer Research and de Duve Institute, Université catholique de Louvain, Brussels 1200, Belgium
| | - Ziao Fu
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Jean-Noel Octave
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Stefan N Constantinescu
- Ludwig Institute for Cancer Research and de Duve Institute, Université catholique de Louvain, Brussels 1200, Belgium
| | - Steven O Smith
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA.
| |
Collapse
|
50
|
Lou B, Chen M, Luo X, Dai Y. Reduced right frontal fractional anisotropy correlated with early elevated plasma LDL levels in obese young adults. PLoS One 2014; 9:e108180. [PMID: 25279729 PMCID: PMC4184805 DOI: 10.1371/journal.pone.0108180] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Accepted: 08/09/2014] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE To investigate the underlying physiological mechanisms of the structural differences in gray matter (GM) and white matter (WM) associated with obesity in young Chinese adults. MATERIALS AND METHODS A total of 49 right-handed obese or overweight (n = 22, mean age 31.72±8.04 years) and normal weight (n = 27, mean age 29.04±7.32 years) Han Chinese individuals were recruited. All participants underwent voxel-based morphometry analysis of T1-weighted MRI and tract-based spatial statistics analysis of diffusion tensor imaging. Partial correlation analysis was performed between the physiological data obtained and the abnormal structural alterations. RESULTS In the OO group, GM atrophy occurred in the left prefrontal cortex, bilateral cingulate gyrus, and the right temporal lobe, while enlargement was observed in the bilateral putamen. WM atrophy was observed predominantly in the regions that regulate food intake, such as the bilateral basal ganglia, the right amygdala, and the left insula. The OO group exhibited lower fractional anisotropy (FA) in bilateral frontal corticospinal tracts and the right brainstem. Significant negative correlations were observed between FA values of those three clusters and BMI, and waist circumference, while the volume of bilateral putamen positively correlated with both BMI and waist circumference. High plasma LDL levels were correlated with low FA values in the right frontal corticospinal tract. Interestingly, the negative correlation was limited to male participants. CONCLUSIONS Obesity-related alterations of GM and WM volumes were observed predominantly in food reward circuit, which may motivate abnormal dietary intake. Further, early elevated plasma LDL might contribute to low right frontal FA values of male adults, which requires further demonstration by larger-scale and longitudinal studies.
Collapse
Affiliation(s)
- Baohui Lou
- Graduate School of Peking Union Medical College, Beijing, China
- Beijing Institute of Geriatrics, Beijing Hospital, Beijing, China
| | - Min Chen
- Graduate School of Peking Union Medical College, Beijing, China
- Department of Radiology, Beijing Hospital, Beijing, China
- * E-mail:
| | - Xiaojie Luo
- Department of Radiology, Beijing Hospital, Beijing, China
| | | |
Collapse
|