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Azargoonjahromi A. The duality of amyloid-β: its role in normal and Alzheimer's disease states. Mol Brain 2024; 17:44. [PMID: 39020435 PMCID: PMC11256416 DOI: 10.1186/s13041-024-01118-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 07/14/2024] [Indexed: 07/19/2024] Open
Abstract
Alzheimer's disease (AD) is a degenerative neurological condition that gradually impairs cognitive abilities, disrupts memory retention, and impedes daily functioning by impacting the cells of the brain. A key characteristic of AD is the accumulation of amyloid-beta (Aβ) plaques, which play pivotal roles in disease progression. These plaques initiate a cascade of events including neuroinflammation, synaptic dysfunction, tau pathology, oxidative stress, impaired protein clearance, mitochondrial dysfunction, and disrupted calcium homeostasis. Aβ accumulation is also closely associated with other hallmark features of AD, underscoring its significance. Aβ is generated through cleavage of the amyloid precursor protein (APP) and plays a dual role depending on its processing pathway. The non-amyloidogenic pathway reduces Aβ production and has neuroprotective and anti-inflammatory effects, whereas the amyloidogenic pathway leads to the production of Aβ peptides, including Aβ40 and Aβ42, which contribute to neurodegeneration and toxic effects in AD. Understanding the multifaceted role of Aβ, particularly in AD, is crucial for developing effective therapeutic strategies that target Aβ metabolism, aggregation, and clearance with the aim of mitigating the detrimental consequences of the disease. This review aims to explore the mechanisms and functions of Aβ under normal and abnormal conditions, particularly in AD, by examining both its beneficial and detrimental effects.
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Foley KE, Wilcock DM. Three major effects of APOE ε4 on Aβ immunotherapy induced ARIA. Front Aging Neurosci 2024; 16:1412006. [PMID: 38756535 PMCID: PMC11096466 DOI: 10.3389/fnagi.2024.1412006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 04/23/2024] [Indexed: 05/18/2024] Open
Abstract
The targeting of amyloid-beta (Aβ) plaques therapeutically as one of the primary causes of Alzheimer's disease (AD) dementia has been an ongoing effort spanning decades. While some antibodies are extremely promising and have been moved out of clinical trials and into the clinic, most of these treatments show similar adverse effects in the form of cerebrovascular damage known as amyloid-related imaging abnormalities (ARIA). The two categories of ARIA are of major concern for patients, families, and prescribing physicians, with ARIA-E presenting as cerebral edema, and ARIA-H as cerebral hemorrhages (micro- and macro-). From preclinical and clinical trials, it has been observed that the greatest genetic risk factor for AD, APOEε4, is also a major risk factor for anti-Aβ immunotherapy-induced ARIA. APOEε4 carriers represent a large population of AD patients, and, therefore, limits the broad adoption of these therapies across the AD population. In this review we detail three hypothesized mechanisms by which APOEε4 influences ARIA risk: (1) reduced cerebrovascular integrity, (2) increased neuroinflammation and immune dysregulation, and (3) elevated levels of CAA. The effects of APOEε4 on ARIA risk is clear, however, the underlying mechanisms require more research.
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Affiliation(s)
- Kate E. Foley
- Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN, United States
- Department of Neurology, School of Medicine, Indiana University, Indianapolis, IN, United States
| | - Donna M. Wilcock
- Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN, United States
- Department of Neurology, School of Medicine, Indiana University, Indianapolis, IN, United States
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Liu X, Beck T, Dhana K, Tangney CC, Desai P, Krueger K, Evans DA, Rajan KB. Dietary fats and the APOE-e4 risk allele in relation to cognitive decline: a longitudinal investigation in a biracial population sample. J Nutr Health Aging 2024; 28:100211. [PMID: 38507884 DOI: 10.1016/j.jnha.2024.100211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/05/2024] [Accepted: 03/06/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND APOE-e4 is the strongest genetic risk factor for Alzheimer's disease. However, the influence of APOE-e4 on dietary fat intake and cognition has not been investigated. OBJECTIVE We aim to examine the association of types of dietary fat and their association to cognitive decline among those with and without the APOE-e4 allele. METHODS The study included 3,360 Chicago Health and Aging Project (CHAP) participants from four Southside Chicago communities. Global cognition was assessed using a composite score of episodic memory, perceptual speed, MMSE, and diet using a 144-item food frequency questionnaire. APOE genotype was assessed by the hME Sequenom mass-array platform. Longitudinal mixed-effect regression models were used to examine the association of dietary fat and the APOE-e4 allele with cognitive decline, adjusted for age, sex, education, smoking status, and calorie intake. RESULTS The present study involved 3,360 participants with a mean age of 74 at baseline, 62% African Americans, 63% females, and a mean follow-up of 7.8 years. Among participants with the APOE-e4 risk allele, higher intakes of total and saturated fat (SFA) were associated with a faster decline in global cognition. Among individuals with the APOE-e4 risk allele, a 5% increase in calories from SFA was associated with a 21% faster decline (β = -0.0197, P = 0.0038). In contrast, a higher intake of long-chain n-3 polyunsaturated fatty acids (LC-n3 PUFA) was associated with a slower rate of decline in global cognition among APOE-e4 carriers. Specifically, for every 1% energy increment from LC-n3 PUFA, the annual rate of global cognitive decline was slower by 0.024 standardized unit (SD 0.010, P = 0.023), about 30.4% slower annual cognitive decline. Higher SFA or other types of dietary fat were not associated with cognitive decline among APOE-e4 non-carriers. CONCLUSIONS Our study found a significant association between SFA and faster cognitive decline, LC-n3 PUFA and slower cognitive decline among those with the APOE-e4 allele. Our findings suggested that higher intake of SFA might contribute faster cognitive decline in combination with APOE-e4 whereas LC-n3 PUFA might compensate the adverse effects of APOE-e4. The interaction between intakes of different types of dietary fat and APOE-e4 on cognitive function warrants further research.
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Affiliation(s)
- Xiaoran Liu
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA.
| | - Todd Beck
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Klodian Dhana
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Christy C Tangney
- Department of Clinical Nutrition & Preventive Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Pankaja Desai
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Kristin Krueger
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Denis A Evans
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Kumar B Rajan
- Rush Institute for Healthy Aging, Rush University Medical Center, Chicago, IL, USA; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
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Ritchie M, Sajjadi SA, Grill JD. Apolipoprotein E Genetic Testing in a New Age of Alzheimer Disease Clinical Practice. Neurol Clin Pract 2024; 14:e200230. [PMID: 38223345 PMCID: PMC10783973 DOI: 10.1212/cpj.0000000000200230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 11/01/2023] [Indexed: 01/16/2024]
Abstract
The recent FDA approval of amyloid-lowering drugs is changing the landscape of Alzheimer disease (AD) clinical practice. Previously, apolipoprotein E (APOE) genetic testing was not recommended in the care of people with AD because of limited clinical utility. With the advent of amyloid-lowering drugs, APOE genotype will play an important role in guiding treatment recommendations. Recent clinical trials have reported strong associations between APOE genotype and the safety and possibly the efficacy of amyloid-lowering drugs. Therefore, a clinical workflow that includes biomarker and genetic testing should be implemented to provide patients with the opportunity to make informed decisions and instruct safety monitoring for clinicians. Pretest consent, education, and counseling will be an essential aspect of this process for patients and their family members to understand the implications of these tests and their results. Given that the approved amyloid-lowering drugs are indicated for patients with mild cognitive impairment or mild dementia with biomarker evidence of AD, biomarker testing should be performed before genetic testing and genetic testing should only be performed in patients interested in treatment with amyloid-lowering drugs. It is also important to consider other implications of genetic testing, including burden on and need for additional training for clinicians, the role of additional providers, and the potential challenges for patients and families.
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Affiliation(s)
- Marina Ritchie
- UC Irvine Institute for Memory Impairments and Neurological Disorders (MR, SAS); Department of Neurobiology and Behavior (MR); Department of Neurology (SAS); and Department of Psychiatry and Human Behavior, University of California, Irvine
| | - Seyed Ahmad Sajjadi
- UC Irvine Institute for Memory Impairments and Neurological Disorders (MR, SAS); Department of Neurobiology and Behavior (MR); Department of Neurology (SAS); and Department of Psychiatry and Human Behavior, University of California, Irvine
| | - Joshua D Grill
- UC Irvine Institute for Memory Impairments and Neurological Disorders (MR, SAS); Department of Neurobiology and Behavior (MR); Department of Neurology (SAS); and Department of Psychiatry and Human Behavior, University of California, Irvine
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Tokunaga A, Kimura N, Masuda T, Hanaoka T, Matsubara E. Objectively measured prolonged sleep is associated with plasma cytokines in older adults with mild cognitive impairment. J Sleep Res 2024:e14135. [PMID: 38212137 DOI: 10.1111/jsr.14135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 12/13/2023] [Accepted: 12/15/2023] [Indexed: 01/13/2024]
Abstract
This study aimed to determine whether objective sleep time is associated with the concentrations of various plasma cytokines in older adults with mild cognitive impairment (MCI). In total, 118 adults with MCI (66 women; mean age: 75.7 years) participated in this prospective cohort study. All participants were required to wear a wristband sensor for 7.8 days, on average, every 3 months for 1 year and undergo measurement of 27 plasma cytokines using multiplex immunoassays. After adjusting for potential confounders, the associations of total sleep time with cytokine concentrations were assessed by multiple linear regression analysis. The total sleep time was significantly correlated with plasma interleukin (IL)-9 and macrophage inflammatory protein (MIP)-1β levels (r = 0.239, p = 0.009, and r = 0.242, p = 0.008, respectively). Moreover, these associations remained significant after adjusting for covariates, including demographic characteristics, lifestyle-related diseases, and apolipoprotein E status (β = 0.272, 95% confidence interval: 0.095-0.448, p = 0.003, and β = 0.27, 95% confidence interval: 0.092-0.449, p = 0.003, respectively). Thus, this study is the first to demonstrate the association between objective prolonged sleep and higher plasma IL-9 and MIP-1β levels in older adults with MCI.
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Affiliation(s)
- Akari Tokunaga
- Department of Neurology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Noriyuki Kimura
- Department of Neurology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Teruaki Masuda
- Department of Neurology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Takuya Hanaoka
- Department of Neurology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Etsuro Matsubara
- Department of Neurology, Faculty of Medicine, Oita University, Yufu, Japan
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Asiamah EA, Feng B, Guo R, Yaxing X, Du X, Liu X, Zhang J, Cui H, Ma J. The Contributions of the Endolysosomal Compartment and Autophagy to APOEɛ4 Allele-Mediated Increase in Alzheimer's Disease Risk. J Alzheimers Dis 2024; 97:1007-1031. [PMID: 38306054 DOI: 10.3233/jad-230658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Apolipoprotein E4 (APOE4), although yet-to-be fully understood, increases the risk and lowers the age of onset of Alzheimer's disease (AD), which is the major cause of dementia among elderly individuals. The endosome-lysosome and autophagy pathways, which are necessary for homeostasis in both neurons and glia, are dysregulated even in early AD. Nonetheless, the contributory roles of these pathways to developing AD-related pathologies in APOE4 individuals and models are unclear. Therefore, this review summarizes the dysregulations in the endosome-lysosome and autophagy pathways in APOE4 individuals and non-human models, and how these anomalies contribute to developing AD-relevant pathologies. The available literature suggests that APOE4 causes endosomal enlargement, increases endosomal acidification, impairs endosomal recycling, and downregulates exosome production. APOE4 impairs autophagy initiation and inhibits basal autophagy and autophagy flux. APOE4 promotes lysosome formation and trafficking and causes ApoE to accumulate in lysosomes. APOE4-mediated changes in the endosome, autophagosome and lysosome could promote AD-related features including Aβ accumulation, tau hyperphosphorylation, glial dysfunction, lipid dyshomeostasis, and synaptic defects. ApoE4 protein could mediate APOE4-mediated endosome-lysosome-autophagy changes. ApoE4 impairs vesicle recycling and endosome trafficking, impairs the synthesis of autophagy genes, resists being dissociated from its receptors and degradation, and forms a stable folding intermediate that could disrupt lysosome structure. Drugs such as molecular correctors that target ApoE4 molecular structure and enhance autophagy may ameliorate the endosome-lysosome-autophagy-mediated increase in AD risk in APOE4 individuals.
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Affiliation(s)
- Ernest Amponsah Asiamah
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Department of Biomedical Sciences, College of Health and Allied Sciences, University of Cape Coast, PMB UCC, Cape Coast, Ghana
| | - Baofeng Feng
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
- Hebei Technology Innovation Center for Stem Cell and Regenerative Medicine, Hebei, China
| | - Ruiyun Guo
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Xu Yaxing
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Xiaofeng Du
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Xin Liu
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Jinyu Zhang
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Huixian Cui
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
- Hebei Technology Innovation Center for Stem Cell and Regenerative Medicine, Hebei, China
| | - Jun Ma
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
- Hebei Technology Innovation Center for Stem Cell and Regenerative Medicine, Hebei, China
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Malvaso A, Gatti A, Negro G, Calatozzolo C, Medici V, Poloni TE. Microglial Senescence and Activation in Healthy Aging and Alzheimer's Disease: Systematic Review and Neuropathological Scoring. Cells 2023; 12:2824. [PMID: 38132144 PMCID: PMC10742050 DOI: 10.3390/cells12242824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023] Open
Abstract
The greatest risk factor for neurodegeneration is the aging of the multiple cell types of human CNS, among which microglia are important because they are the "sentinels" of internal and external perturbations and have long lifespans. We aim to emphasize microglial signatures in physiologic brain aging and Alzheimer's disease (AD). A systematic literature search of all published articles about microglial senescence in human healthy aging and AD was performed, searching for PubMed and Scopus online databases. Among 1947 articles screened, a total of 289 articles were assessed for full-text eligibility. Microglial transcriptomic, phenotypic, and neuropathological profiles were analyzed comprising healthy aging and AD. Our review highlights that studies on animal models only partially clarify what happens in humans. Human and mice microglia are hugely heterogeneous. Like a two-sided coin, microglia can be protective or harmful, depending on the context. Brain health depends upon a balance between the actions and reactions of microglia maintaining brain homeostasis in cooperation with other cell types (especially astrocytes and oligodendrocytes). During aging, accumulating oxidative stress and mitochondrial dysfunction weaken microglia leading to dystrophic/senescent, otherwise over-reactive, phenotype-enhancing neurodegenerative phenomena. Microglia are crucial for managing Aβ, pTAU, and damaged synapses, being pivotal in AD pathogenesis.
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Affiliation(s)
- Antonio Malvaso
- IRCCS “C. Mondino” Foundation, National Neurological Institute, Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; (A.M.); (A.G.)
| | - Alberto Gatti
- IRCCS “C. Mondino” Foundation, National Neurological Institute, Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; (A.M.); (A.G.)
| | - Giulia Negro
- Department of Neurology, University of Milano Bicocca, 20126 Milan, Italy;
| | - Chiara Calatozzolo
- Department of Neurology and Neuropathology, Golgi-Cenci Foundation, Abbiategrasso, 20081 Milan, Italy;
| | - Valentina Medici
- Department of Translational Medicine, University of Eastern Piedmont, 28100 Novara, Italy;
| | - Tino Emanuele Poloni
- Department of Neurology and Neuropathology, Golgi-Cenci Foundation, Abbiategrasso, 20081 Milan, Italy;
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Gaber HA, Aly EM, Mohamed ES, Elfoly M, Rabie MA, Talaat MS, El-Sayed ESM. Linking Cognitive Impairment with Amyloid-β Accumulation in Alzheimer's Disease: Insights from Behavioral Tests and FTIR Spectroscopy. J Alzheimers Dis Rep 2023; 7:1187-1200. [PMID: 38025802 PMCID: PMC10657722 DOI: 10.3233/adr-230051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 10/02/2023] [Indexed: 12/01/2023] Open
Abstract
Background Alzheimer's disease (AD) is a neurodegenerative disorder that progresses over time. Fourier Transform Infrared Spectroscopy (FTIR) analysis gives identification of the main metabolic changes that happen during neurodegeneration, by monitoring biochemical and molecular structure alterations that can help in AD diagnosis or treatment approach. Objective The aim of the present work is to assess AD hallmarks in molecular structure of retina and monitor accumulation of amyloid beta42(Aβ42) in brain and retina during disease progression. Methods AD induced in rats by Aluminum Chloride (AlCl3). Retinal molecular structure during disease progression for 2,4,6 and 8 weeks was assessed by Fourier-transform infrared spectroscopy (FTIR) and the incidence of the disease was confirmed by a behavioural assessment; the Morris Water Maze test. Aβ42 levels in the brain and retina were also measured. Results The results indicated that cognitive impairment starting from 6 weeks of AlCl3 administration. Retinal concentration of Aβ42 was significant increase (p < 0.05) from 2 weeks that precedes the observed increase of Aβ42 in the brain which appeared after 4 weeks of AlCl3 administration. Multivariate principal component analysis discovers that the variance noticed in the infrared spectra due to AD condition and it is time dependent for progression of the disease. Conclusions The accumulation of Aβ42 is a sensitive early biomarker in retina for AD. FTIR analysis of the retina revealed changes in hydrogen bond formation or destruction, alterations in lipid chain length and branching accompanied by depleted lipid content and carbonization, as well as degeneration of the retinal tissue due to AD.
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Affiliation(s)
- Heba Ahmed Gaber
- Biophysics and Laser Science Unit, Visual Science Department, Research Institute of Ophthalmology, Giza, Egypt
| | - Eman Mohamed Aly
- Biophysics and Laser Science Unit, Visual Science Department, Research Institute of Ophthalmology, Giza, Egypt
| | - Eman Saad Mohamed
- Biophysics and Laser Science Unit, Visual Science Department, Research Institute of Ophthalmology, Giza, Egypt
| | - Marwa Elfoly
- Ophthalmology Department, Research Institute of Ophthalmology, Giza, Egypt
| | - Mostafa Adel Rabie
- Pharmacology and Toxicology Department, Pharmacy College, Cairo University, Cairo, Egypt
| | - Mona Salah Talaat
- Biophysics Department, Science College, Ain Shams University, Cairo, Egypt
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Balu D, Valencia-Olvera AC, Islam Z, Mielczarek C, Hansen A, Perez Ramos TM, York J, LaDu MJ, Tai LM. APOE genotype and sex modulate Alzheimer's disease pathology in aged EFAD transgenic mice. Front Aging Neurosci 2023; 15:1279343. [PMID: 38020764 PMCID: PMC10644540 DOI: 10.3389/fnagi.2023.1279343] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 10/10/2023] [Indexed: 12/01/2023] Open
Abstract
Increasing evidence supports that age, APOE and sex interact to modulate Alzheimer's disease (AD) risk, however the underlying pathways are unclear. One way that AD risk factors may modulate cognition is by impacting amyloid beta (Aβ) accumulation as plaques, and/or neuroinflammation Therefore, the goal of the present study was to evaluate the extent to which age, APOE and sex modulate Aβ pathology, neuroinflammation and behavior in vivo. To achieve this goal, we utilized the EFAD mice, which express human APOE3 or APOE4 and have five familial AD mutations (FAD) that result in Aβ42 overproduction. We assessed Aβ levels, reactive glia and Morris water maze performance in 6-, 10-, 14-, and 18-month-old EFAD mice. Female APOE4 mice had the highest Aβ deposition, fibrillar amyloid deposits and neuroinflammation as well as earlier behavior deficits. Interestingly, we found that female APOE3 mice and male APOE4 mice had similar levels of pathology. Collectively our data support that the combination of APOE4 and female sex is the most detrimental combination for AD, and that at older ages, female sex may be equivalent to APOE4 genotype.
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Affiliation(s)
- Deebika Balu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Ana C. Valencia-Olvera
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Zarak Islam
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
- University of Illinois College of Medicine, Chicago, IL, United States
| | - Clare Mielczarek
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Allison Hansen
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
- University of Illinois College of Medicine, Peoria, IL, United States
| | - Tamara M. Perez Ramos
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
- School of Medicine, St. George’s University, St. George’s, Grenada
| | - Jason York
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Mary Jo LaDu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
| | - Leon M. Tai
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States
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Balu D, Valencia-Olvera AC, Nguyen A, Patnam M, York J, Peri F, Neumann F, LaDu MJ, Tai LM. A small-molecule TLR4 antagonist reduced neuroinflammation in female E4FAD mice. Alzheimers Res Ther 2023; 15:181. [PMID: 37858252 PMCID: PMC10585767 DOI: 10.1186/s13195-023-01330-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 10/10/2023] [Indexed: 10/21/2023]
Abstract
BACKGROUND APOE genotype is the greatest genetic risk factor for sporadic Alzheimer's disease (AD). APOE4 increases AD risk up to 12-fold compared to APOE3, an effect that is greater in females. Evidence suggests that one-way APOE could modulate AD risk and progression through neuroinflammation. Indeed, APOE4 is associated with higher glial activation and cytokine levels in AD patients and mice. Therefore, identifying pathways that contribute to APOE4-associated neuroinflammation is an important approach for understanding and treating AD. Human and in vivo evidence suggests that TLR4, one of the key receptors involved in the innate immune system, could be involved in APOE-modulated neuroinflammation. Consistent with that idea, we previously demonstrated that the TLR4 antagonist IAXO-101 can reduce LPS- and Aβ-induced cytokine secretion in APOE4 glial cultures. Therefore, the goal of this study was to advance these findings and determine whether IAXO-101 can modulate neuroinflammation, Aβ pathology, and behavior in mice that express APOE4. METHODS We used mice that express five familial AD mutations and human APOE3 (E3FAD) or APOE4 (E4FAD). Female and male E4FAD mice and female E3FAD mice were treated with vehicle or IAXO-101 in two treatment paradigms: prevention from 4 to 6 months of age or reversal from 6 to 7 months of age. Learning and memory were assessed by modified Morris water maze. Aβ deposition, fibrillar amyloid deposition, astrogliosis, and microgliosis were assessed by immunohistochemistry. Soluble levels of Aβ and apoE, insoluble levels of apoE and Aβ, and IL-1β were measured by ELISA. RESULTS IAXO-101 treatment resulted in lower Iba-1 coverage, lower number of reactive microglia, and improved memory in female E4FAD mice in both prevention and reversal paradigms. IAXO-101-treated male E4FAD mice also had lower Iba-1 coverage and reactivity in the RVS paradigm, but there was no effect on behavior. There was also no effect of IAXO-101 treatment on neuroinflammation and behavior in female E3FAD mice. CONCLUSION Our data supports that TLR4 is a potential mechanistic therapeutic target for modulating neuroinflammation and cognition in APOE4 females.
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Affiliation(s)
- Deebika Balu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Ana C Valencia-Olvera
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Austin Nguyen
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Mehul Patnam
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Jason York
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Francesco Peri
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | | | - Mary Jo LaDu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Leon M Tai
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA.
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Minné D, Stromin J, Docrat T, Engel-Hills P, Marnewick JL. The effects of tea polyphenols on emotional homeostasis: Understanding dementia risk through stress, mood, attention & sleep. Clin Nutr ESPEN 2023; 57:77-88. [PMID: 37739736 DOI: 10.1016/j.clnesp.2023.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 04/18/2023] [Accepted: 06/11/2023] [Indexed: 09/24/2023]
Abstract
Decades of research provide evidence that certain phytochemicals in tea (Camellia sinensis) and other herbal beverages are protective against the development of sporadic types of dementia in later life. Since tea drinking is an economical and widely adopted social-cultural practice across all age groups, it is an ideal product to target in designing low-cost dietary interventions for Alzheimer's Disease (AD), the most prevalent form of dementia. In this review, we focus on the protective roles of tea-derived polyphenols and other phytochemicals on mood, the stress response, attention, and sleep, in keeping with the perspective that many early neuropathological events in AD may stem, in part, from allostatic overload. This approach aligns with the perspective that many forms of dementia, including AD, begin to take root in the brain decades prior to symptom onset, underscoring the need for early uptake of accessible and viable lifestyle interventions. The findings reviewed here suggest that consuming green and oolong tea can improve mood and reduce overall stress. However, given the caffeine content in tea and its association with stress reactivity, the effects of daily whole tea consumption on the emotional state are likely dose-dependent with an inverted-U relationship to wellbeing. Plant-based beverages that are to be consumed in high daily quantities for health purposes and which are naturally free of caffeine, such as Rooibos, may be more appropriate as a dietary supplement for managing emotional regulation over the lifetime.
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Affiliation(s)
- Donné Minné
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa; Health and Wellness Sciences Faculty, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Juliet Stromin
- Psychology Department, University of Cape Town, Lover's Walk, Rondebosch, Cape Town, 7700, South Africa.
| | - Taskeen Docrat
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Penelope Engel-Hills
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa; Health and Wellness Sciences Faculty, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Jeanine L Marnewick
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
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12
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Abyadeh M, Gupta V, Paulo JA, Sheriff S, Shadfar S, Fitzhenry M, Amirkhani A, Gupta V, Salekdeh GH, Haynes PA, Graham SL, Mirzaei M. Apolipoprotein ε in Brain and Retinal Neurodegenerative Diseases. Aging Dis 2023; 14:1311-1330. [PMID: 37199411 PMCID: PMC10389820 DOI: 10.14336/ad.2023.0312-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/12/2023] [Indexed: 05/19/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia that remains incurable and has become a major medical, social, and economic challenge worldwide. AD is characterized by pathological hallmarks of senile plaques (SP) and neurofibrillary tangles (NFTs) that damage the brain up to twenty years before a clinical diagnosis is made. Interestingly these pathological features have also been observed in retinal neurodegenerative diseases including age related macular degeneration (ARMD), glaucoma and diabetic retinopathy (DR). An association of AD with these diseases has been suggested in epidemiological studies and several common pathological events and risk factors have been identified between these diseases. The E4 allele of Apolipoprotein E (APOE) is a well-established genetic risk factor for late onset AD. The ApoE ε4 allele is also associated with retinal neurodegenerative diseases however in contrast to AD, it is considered protective in AMD, likewise ApoE E2 allele, which is a protective factor for AD, has been implicated as a risk factor for AMD and glaucoma. This review summarizes the evidence on the effects of ApoE in retinal neurodegenerative diseases and discusses the overlapping molecular pathways in AD. The involvement of ApoE in regulating amyloid beta (Aβ) and tau pathology, inflammation, vascular integrity, glucose metabolism and vascular endothelial growth factor (VEGF) signaling is also discussed.
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Affiliation(s)
| | - Vivek Gupta
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW 2109, Australia.
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
| | - Samran Sheriff
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW 2109, Australia.
| | - Sina Shadfar
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW 2109, Australia.
| | - Matthew Fitzhenry
- Australian Proteome Analysis Facility, Macquarie University, Macquarie Park, NSW 2113, Australia.
| | - Ardeshir Amirkhani
- Australian Proteome Analysis Facility, Macquarie University, Macquarie Park, NSW 2113, Australia.
| | - Veer Gupta
- School of Medicine, Deakin University, VIC, Australia.
| | - Ghasem H Salekdeh
- School of Natural Sciences, Macquarie University, Macquarie Park, NSW 2109, Australia.
| | - Paul A Haynes
- School of Natural Sciences, Macquarie University, Macquarie Park, NSW 2109, Australia.
| | - Stuart L Graham
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW 2109, Australia.
| | - Mehdi Mirzaei
- Department of Clinical Medicine, Faculty of Medicine, Health and Human Sciences, Macquarie Medical School, Macquarie University, Macquarie Park, North Ryde, Sydney, NSW 2109, Australia.
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13
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Kuhn MK, Fleeman RM, Beidler LM, Snyder AM, Chan DC, Proctor EA. Amyloid-β Pathology-Specific Cytokine Secretion Suppresses Neuronal Mitochondrial Metabolism. Cell Mol Bioeng 2023; 16:405-421. [PMID: 37811007 PMCID: PMC10550897 DOI: 10.1007/s12195-023-00782-y] [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: 02/17/2023] [Accepted: 08/28/2023] [Indexed: 10/10/2023] Open
Abstract
Introduction Neuroinflammation and metabolic dysfunction are early alterations in Alzheimer's disease (AD) brain that are thought to contribute to disease onset and progression. Glial activation due to protein deposition results in cytokine secretion and shifts in brain metabolism, which have been observed in AD patients. However, the mechanism by which this immunometabolic feedback loop can injure neurons and cause neurodegeneration remains unclear. Methods We used Luminex XMAP technology to quantify hippocampal cytokine concentrations in the 5xFAD mouse model of AD at milestone timepoints in disease development. We used partial least squares regression to build cytokine signatures predictive of disease progression, as compared to healthy aging in wild-type littermates. We applied the disease-defining cytokine signature to wild-type primary neuron cultures and measured downstream changes in gene expression using the NanoString nCounter system and mitochondrial function using the Seahorse Extracellular Flux live-cell analyzer. Results We identified a pattern of up-regulated IFNγ, IP-10/CXCL10, and IL-9 as predictive of advanced disease. When healthy neurons were exposed to these cytokines in proportions found in diseased brain, gene expression of mitochondrial electron transport chain complexes, including ATP synthase, was suppressed. In live cells, basal and maximal mitochondrial respiration were impaired following cytokine stimulation. Conclusions We identify a pattern of cytokine secretion predictive of progressing amyloid-β pathology in the 5xFAD mouse model of AD that reduces expression of mitochondrial electron transport complexes and impairs mitochondrial respiration in healthy neurons. We establish a mechanistic link between disease-specific immune cues and impaired neuronal metabolism, potentially causing neuronal vulnerability and susceptibility to degeneration in AD. Supplementary Information The online version contains supplementary material available at 10.1007/s12195-023-00782-y.
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Affiliation(s)
- Madison K. Kuhn
- Department of Neurosurgery, Penn State College of Medicine, Hershey, USA
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA USA
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA USA
- Center for Neural Engineering, Pennsylvania State University, University Park, PA USA
| | - Rebecca M. Fleeman
- Department of Neurosurgery, Penn State College of Medicine, Hershey, USA
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA USA
| | - Lynne M. Beidler
- Department of Microbiology & Immunology, Penn State College of Medicine, Hershey, PA USA
| | - Amanda M. Snyder
- Department of Neurology, Penn State College of Medicine, Hershey, PA USA
| | - Dennis C. Chan
- Department of Neurosurgery, Penn State College of Medicine, Hershey, USA
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA USA
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA USA
- Center for Neural Engineering, Pennsylvania State University, University Park, PA USA
| | - Elizabeth A. Proctor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, USA
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA USA
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA USA
- Department of Engineering Science & Mechanics, Pennsylvania State University, University Park, PA USA
- Center for Neural Engineering, Pennsylvania State University, University Park, PA USA
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14
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Kloske CM, Gearon MD, Weekman EM, Rogers C, Patel E, Bachstetter A, Nelson PT, Wilcock DM. Association between APOE genotype and microglial cell morphology. J Neuropathol Exp Neurol 2023; 82:620-630. [PMID: 37087107 PMCID: PMC10280358 DOI: 10.1093/jnen/nlad031] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/24/2023] Open
Abstract
APOE is the largest genetic risk factor for late-onset Alzheimer disease (AD) with E4 conferring an increased risk for AD compared to E3. The ApoE protein can impact diverse pathways in the brain including neuroinflammation but the precise impact of ApoE isoforms on inflammation remains unknown. As microglia are a primary source of neuroinflammation, this study determined whether ApoE isoforms have an impact on microglial morphology and activation using immunohistochemistry and digital analyses. Analysis of ionized calcium-binding adaptor molecule 1 (Iba1) immunoreactivity indicated greater microglial activation in both the hippocampus and superior and middle temporal gyrus (SMTG) in dementia participants versus non-demented controls. Further, only an increase in activation was seen in E3-Dementia participants in the entire SMTG, whereas in the grey matter of the SMTG, only a diagnosis of dementia impacted activation. Specific microglial morphologies showed a reduction in ramified microglia in the dementia group. For rod microglia, a reduction was seen in E4-Control patients in the hippocampus whereas in the SMTG an increase was seen in E4-Dementia patients. These findings suggest an association between ApoE isoforms and microglial morphologies and highlight the importance of considering ApoE isoforms in studies of AD pathology.
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Affiliation(s)
- Courtney M Kloske
- Department of Physiology, College of Medicine, Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | - Mary D Gearon
- Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Erica M Weekman
- Department of Physiology, College of Medicine, Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | - Colin Rogers
- Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Ela Patel
- Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Adam Bachstetter
- Department of Neuroscience, College of Medicine, Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | - Peter T Nelson
- Department of Pathology and Laboratory Medicine, College of Medicine, Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | - Donna M Wilcock
- Department of Physiology, College of Medicine, Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
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15
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Vipin A, Kumar D, Soo SA, Zailan FZ, Leow YJ, Koh CL, Ng ASL, Ng KP, Kandiah N. APOE4 carrier status determines association between white matter disease and grey matter atrophy in early-stage dementia. Alzheimers Res Ther 2023; 15:103. [PMID: 37270543 DOI: 10.1186/s13195-023-01251-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 05/29/2023] [Indexed: 06/05/2023]
Abstract
BACKGROUND White matter hyperintensities, a neuroimaging marker of small-vessel cerebrovascular disease and apolipoprotein ε4 (APOE4) allele, are important dementia risk factors. However, APOE4 as a key effect modifier in the relationship between white matter hyperintensities and grey matter volume needs further exploration. METHODS One hundred ninety-two early-stage dementia (including mild cognitive impairment and mild dementia) and 259 cognitively unimpaired participants from a neurocognitive research cohort with neuroimaging data, APOE genotyping, and neuropsychological assessments were studied. We investigated independent and interactive effects of white matter hyperintensities and APOE4 on whole-brain voxel-wise grey matter volume using voxel-based morphometry (uncorrected p < 0.001; minimum cluster size = 100 voxels). We further assessed interactive effects between APOE4 and white matter hyperintensities on global cognition, memory, and executive function in early-stage dementia and cognitively unimpaired participants. RESULTS Independent of APOE4 status, higher white matter hyperintensity load was associated with greater grey matter atrophy across frontal, parietal, temporal, and occipital lobes in cognitively unimpaired and early-stage dementia subjects. However, interaction analyses and independent sample analyses revealed that APOE4 non-carriers demonstrated greater white matter hyperintensity-associated grey matter atrophy compared to APOE4 carriers in both cognitively unimpaired and early-stage dementia groups. Additional confirmatory analyses among APOE4 non-carriers demonstrated that white matter hyperintensities resulted in widespread grey matter loss. Analyses of cognitive function demonstrated that higher white matter hyperintensity load was associated with worse global (Mini-Mental State Examination, Montreal Cognitive Assessment) and executive function (Color Trails 2) in APOE4 non-carriers compared to APOE4 carriers in early-stage dementia but not cognitively unimpaired participants. CONCLUSIONS The association between white matter hyperintensities and grey matter loss is more pronounced in APOE4 non-carriers than APOE4 carriers in the cognitively unimpaired and early-stage dementia stages. Furthermore, white matter hyperintensity presence results in poorer executive function in APOE4 non-carriers compared to APOE4 carriers. This finding may have significant impact on the design of clinical trials with disease modifying therapies.
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Grants
- MOE AcRF Tier 3 Award MOE2017-T3-1-002 Ministry of Education - Singapore
- MOE AcRF Tier 3 Award MOE2017-T3-1-002 Ministry of Education - Singapore
- MOE AcRF Tier 3 Award MOE2017-T3-1-002 Ministry of Education - Singapore
- MOE AcRF Tier 3 Award MOE2017-T3-1-002 Ministry of Education - Singapore
- MOE AcRF Tier 3 Award MOE2017-T3-1-002 Ministry of Education - Singapore
- MOE AcRF Tier 3 Award MOE2017-T3-1-002 Ministry of Education - Singapore
- NMRC/CIRG/1415/2015, NMRC/CSA/063/2014, MOH-CSAINV18nov-0007, NMRC/CIRG/14MAY025 National Medical Research Council
- NMRC/CIRG/1415/2015, NMRC/CSA/063/2014, MOH-CSAINV18nov-0007, NMRC/CIRG/14MAY025 National Medical Research Council
- NMRC/CIRG/1415/2015, NMRC/CSA/063/2014, MOH-CSAINV18nov-0007, NMRC/CIRG/14MAY025 National Medical Research Council
- NMRC/CIRG/1415/2015, NMRC/CSA/063/2014, MOH-CSAINV18nov-0007, NMRC/CIRG/14MAY025 National Medical Research Council
- NMRC/CIRG/1415/2015, NMRC/CSA/063/2014, MOH-CSAINV18nov-0007, NMRC/CIRG/14MAY025 National Medical Research Council
- NMRC/CIRG/1415/2015, NMRC/CSA/063/2014, MOH-CSAINV18nov-0007, NMRC/CIRG/14MAY025 National Medical Research Council
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
- Reference Number: 991016 National Neuroscience Institute-Health Research Endowment Fund (NNI-HREF), Singapore
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Affiliation(s)
- Ashwati Vipin
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, Singapore
| | - Dilip Kumar
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, Singapore
| | - See Ann Soo
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, Singapore
| | - Fatin Zahra Zailan
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, Singapore
| | - Yi Jin Leow
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, Singapore
| | - Chen Ling Koh
- National Neuroscience Institute, Singapore, Singapore
| | - Adeline Su Lyn Ng
- National Neuroscience Institute, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - Kok Pin Ng
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - Nagaendran Kandiah
- Dementia Research Centre - Lee Kong Chian School of Medicine, Nanyang Technology University, 11 Mandalay Road, Singapore, 308232, Singapore.
- National Neuroscience Institute, Singapore, Singapore.
- Duke-NUS Medical School, Singapore, Singapore.
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16
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Fleeman RM, Snyder AM, Kuhn MK, Chan DC, Smith GC, Crowley NA, Arnold AC, Proctor EA. Predictive link between systemic metabolism and cytokine signatures in the brain of apolipoprotein E ε4 mice. Neurobiol Aging 2023; 123:154-169. [PMID: 36572594 PMCID: PMC9892258 DOI: 10.1016/j.neurobiolaging.2022.11.015] [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: 06/29/2022] [Revised: 11/23/2022] [Accepted: 11/25/2022] [Indexed: 12/12/2022]
Abstract
The ε4 variant of apolipoprotein E (APOE) is the strongest and most common genetic risk factor for Alzheimer's disease (AD). While the mechanism of conveyed risk is incompletely understood, promotion of inflammation, dysregulated metabolism, and protein misfolding and aggregation are contributors to accelerating disease. Here we determined the concurrent effects of systemic metabolic changes and brain inflammation in young (3-month-old) and aged (18-month-old) male and female mice carrying the APOE4 gene. Using functional metabolic assays alongside multivariate modeling of hippocampal cytokine levels, we found that brain cytokine signatures are predictive of systemic metabolic outcomes, independent of AD proteinopathies. Male and female mice each produce different cytokine signatures as they age and as their systemic metabolic phenotype declines, and these signatures are APOE genotype dependent. Ours is the first study to identify a quantitative and predictive link between systemic metabolism and specific pathological cytokine signatures in the brain. Our results highlight the effects of APOE4 beyond the brain and suggest the potential for bi-directional influence of risk factors in the brain and periphery.
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Affiliation(s)
- Rebecca M Fleeman
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA; Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA
| | - Amanda M Snyder
- Department of Neurology, Penn State College of Medicine, Hershey, PA, USA
| | - Madison K Kuhn
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA; Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA; Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA; Center for Neural Engineering, Pennsylvania State University, University Park, PA, USA
| | - Dennis C Chan
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA; Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA; Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA; Center for Neural Engineering, Pennsylvania State University, University Park, PA, USA
| | - Grace C Smith
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA; Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Nicole A Crowley
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA; Center for Neural Engineering, Pennsylvania State University, University Park, PA, USA; Department of Biology, Pennsylvania State University, University Park, PA, USA
| | - Amy C Arnold
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - Elizabeth A Proctor
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA; Department of Pharmacology, Penn State College of Medicine, Hershey, PA, USA; Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA; Center for Neural Engineering, Pennsylvania State University, University Park, PA, USA; Department of Engineering Science & Mechanics, Pennsylvania State University, University Park, PA, USA.
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17
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Shaikh A, Ahmad F, Teoh SL, Kumar J, Yahaya MF. Honey and Alzheimer's Disease-Current Understanding and Future Prospects. Antioxidants (Basel) 2023; 12:antiox12020427. [PMID: 36829985 PMCID: PMC9952506 DOI: 10.3390/antiox12020427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/30/2023] [Accepted: 02/03/2023] [Indexed: 02/12/2023] Open
Abstract
Alzheimer's disease (AD), a leading cause of dementia, has been a global concern. AD is associated with the involvement of the central nervous system that causes the characteristic impaired memory, cognitive deficits, and behavioral abnormalities. These abnormalities caused by AD is known to be attributed by extracellular aggregates of amyloid beta plaques and intracellular neurofibrillary tangles. Additionally, genetic factors such as abnormality in the expression of APOE, APP, BACE1, PSEN-1, and PSEN-2 play a role in the disease. As the current treatment aims to treat the symptoms and to slow the disease progression, there has been a continuous search for new nutraceutical agent or medicine to help prevent and cure AD pathology. In this quest, honey has emerged as a powerful nootropic agent. Numerous studies have demonstrated that the high flavonoids and phenolic acids content in honey exerts its antioxidant, anti-inflammatory, and neuroprotective properties. This review summarizes the effect of main flavonoid compounds found in honey on the physiological functioning of the central nervous system, and the effect of honey intake on memory and cognition in various animal model. This review provides a new insight on the potential of honey to prevent AD pathology, as well as to ameliorate the damage in the developed AD.
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Affiliation(s)
- Ammara Shaikh
- Department of Anatomy, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
| | - Fairus Ahmad
- Department of Anatomy, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
| | - Seong Lin Teoh
- Department of Anatomy, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
| | - Jaya Kumar
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
| | - Mohamad Fairuz Yahaya
- Department of Anatomy, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
- Correspondence:
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18
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Kirsch D, Shah A, Dixon E, Kelley H, Cherry JD, Xia W, Daley S, Aytan N, Cormier K, Kubilus C, Mathias R, Alvarez VE, Huber BR, McKee AC, Stein TD. Vascular injury is associated with repetitive head impacts and tau pathology in chronic traumatic encephalopathy. J Neuropathol Exp Neurol 2023; 82:127-139. [PMID: 36617181 PMCID: PMC9852946 DOI: 10.1093/jnen/nlac122] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease linked to repetitive head impacts (RHI) and characterized by perivascular hyperphosphorylated tau (p-tau) deposits. The role of vascular injury, blood-brain barrier leakage, and neuroinflammation in CTE pathogenesis is not well understood. We performed quantitative immunoassays for intercellular adhesion molecule 1 (ICAM1), vascular cellular adhesion molecule 1 (VCAM1), and C-reactive protein (CRP) within the postmortem dorsolateral frontal cortex of participants with and without a history of RHI and CTE (n = 156), and tested for associations with RHI, microgliosis, and tau pathology measures. Levels of vascular injury-associated markers ICAM1, VCAM1, and CRP were increased in CTE compared to RHI-exposed and -naïve controls. ICAM1 and CRP increased with RHI exposure duration (p < 0.01) and were associated with increased microglial density (p < 0.001) and tau pathology (AT8, p-tau396, p-tau202; p < 0.05). Histologically, there was significantly increased ICAM1 staining of the microvasculature, extracellular space, and astrocytes at the sulcal depths in high stage CTE compared to both low stage CTE and controls. Multifocal perivascular immunoreactivity for serum albumin was present in all RHI-exposed individuals. These findings demonstrate that vascular injury markers are associated with RHI exposure, duration, and microgliosis, are elevated in CTE, and increase with disease severity.
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Affiliation(s)
- Daniel Kirsch
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Arsal Shah
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
| | - Erin Dixon
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
| | - Hunter Kelley
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
| | - Jonathan D Cherry
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Weiming Xia
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
| | - Sarah Daley
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
| | - Nurgul Aytan
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
| | - Kerry Cormier
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
| | - Carol Kubilus
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
| | - Rebecca Mathias
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
| | - Victor E Alvarez
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Bertrand R Huber
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Ann C McKee
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Thor D Stein
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Boston Healthcare System, Boston, Massachusetts, USA
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
- VA Bedford Healthcare System, Bedford, Massachusetts, USA
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19
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Liver-ing in your head rent free: peripheral ApoE4 drives CNS pathology. Mol Neurodegener 2022; 17:65. [PMID: 36195891 PMCID: PMC9531445 DOI: 10.1186/s13024-022-00569-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 09/22/2022] [Indexed: 11/10/2022] Open
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20
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Seto M, Weiner RL, Dumitrescu L, Mahoney ER, Hansen SL, Janve V, Khan OA, Liu D, Wang Y, Menon V, De Jager PL, Schneider JA, Bennett DA, Gifford KA, Jefferson AL, Hohman TJ. RNASE6 is a novel modifier of APOE-ε4 effects on cognition. Neurobiol Aging 2022; 118:66-76. [PMID: 35896049 PMCID: PMC9721357 DOI: 10.1016/j.neurobiolaging.2022.06.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/25/2022] [Accepted: 06/27/2022] [Indexed: 02/06/2023]
Abstract
Apolipoprotein E4 (APOE-ε4), the strongest common genetic risk factor for Alzheimer's disease (AD), contributes to worse cognition in older adults. However, many APOE-ε4 carriers remain cognitively normal throughout life, suggesting that neuroprotective factors may be present in these individuals. In this study, we leverage whole-blood RNA sequencing (RNAseq) from 324 older adults to identify genetic modifiers of APOE-ε4 effects on cognition. Expression of RNASE6 interacted with APOE-ε4 status (p = 4.35 × 10-8) whereby higher RNASE6 expression was associated with worse memory at baseline among APOE-ε4 carriers. This interaction was replicated using RNAseq data from the prefrontal cortex in an independent dataset (N = 535; p = 0.002), suggesting the peripheral effect of RNASE6 is also present in brain tissue. RNASE6 encodes an antimicrobial peptide involved in innate immune response and has been previously observed in a gene co-expression network module with other AD-related inflammatory genes, including TREM2 and MS4A. Together, these data implicate neuroinflammation in cognitive decline, and suggest that innate immune signaling may be detectable in blood and confer differential susceptibility to AD depending on APOE-ε4.
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Affiliation(s)
- Mabel Seto
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Rebecca L Weiner
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Logan Dumitrescu
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Emily R Mahoney
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Shania L Hansen
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Vaibhav Janve
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Omair A Khan
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Dandan Liu
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Yanling Wang
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Vilas Menon
- Center for Translational & Computational Neuroimmunology, Department of Neurology and the Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Philip L De Jager
- Center for Translational & Computational Neuroimmunology, Department of Neurology and the Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA; Cell Circuits Program, Broad Institute, Cambridge, MA, USA
| | - Julie A Schneider
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Katherine A Gifford
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Angela L Jefferson
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Timothy J Hohman
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.
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21
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Wang S, Li B, Solomon V, Fonteh A, Rapoport SI, Bennett DA, Arvanitakis Z, Chui HC, Sullivan PM, Yassine HN. Calcium-dependent cytosolic phospholipase A 2 activation is implicated in neuroinflammation and oxidative stress associated with ApoE4. Mol Neurodegener 2022; 17:42. [PMID: 35705959 PMCID: PMC9202185 DOI: 10.1186/s13024-022-00549-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 06/03/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Apolipoprotein E4 (APOE4) is associated with a greater response to neuroinflammation and the risk of developing late-onset Alzheimer's disease (AD), but the mechanisms for this association are not clear. The activation of calcium-dependent cytosolic phospholipase A2 (cPLA2) is involved in inflammatory signaling and is elevated within the plaques of AD brains. The relation between APOE4 genotype and cPLA2 activity is not known. METHODS Mouse primary astrocytes, mouse and human brain samples differing by APOE genotypes were collected for measuring cPLA2 expression, phosphorylation, and activity in relation to measures of inflammation and oxidative stress. RESULTS Greater cPLA2 phosphorylation, cPLA2 activity and leukotriene B4 (LTB4) levels were identified in ApoE4 compared to ApoE3 in primary astrocytes, brains of ApoE-targeted replacement (ApoE-TR) mice, and in human brain homogenates from the inferior frontal cortex of persons with AD dementia carrying APOE3/4 compared to APOE3/3. Higher phosphorylated p38 MAPK but not ERK1/2 was found in ApoE4 primary astrocytes and mouse brains than that in ApoE3. Greater cPLA2 translocation to cytosol was observed in human postmortem frontal cortical synaptosomes with recombinant ApoE4 than ApoE3 ex vivo. In ApoE4 astrocytes, the greater levels of LTB4, reactive oxygen species (ROS), and inducible nitric oxide synthase (iNOS) were reduced after cPLA2 inhibition. CONCLUSIONS Our findings implicate greater activation of cPLA2 signaling system with APOE4, which could represent a potential drug target for mitigating the increased neuroinflammation with APOE4 and AD.
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Affiliation(s)
- Shaowei Wang
- Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Boyang Li
- Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Victoria Solomon
- Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Alfred Fonteh
- Huntington Medical Research Institutes, Pasadena, CA USA
| | | | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL USA
| | - Zoe Arvanitakis
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL USA
| | - Helena C. Chui
- Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Patrick M. Sullivan
- Department of Medicine, Duke University Medical Center, Durham Veterans Health Administration Medical Center’s Geriatric Research, Education and Clinical Center, Durham, NC USA
| | - Hussein N. Yassine
- Keck School of Medicine, University of Southern California, Los Angeles, CA USA
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22
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Murray J, Meloni G, Cortes EP, KimSilva A, Jacobs M, Ramkissoon A, Crary JF, Morgello S. Frontal lobe microglia, neurodegenerative protein accumulation, and cognitive function in people with HIV. Acta Neuropathol Commun 2022; 10:69. [PMID: 35526056 PMCID: PMC9080134 DOI: 10.1186/s40478-022-01375-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 04/26/2022] [Indexed: 12/12/2022] Open
Abstract
Microglia are implicated in Alzheimer's Disease (AD) pathogenesis. In a middle-aged cohort enriched for neuroinflammation, we asked whether microgliosis was related to neocortical amyloid beta (A[Formula: see text]) deposition and neuronal phosphorylated tau (p-tau), and whether microgliosis predicted cognition. Frontal lobe tissue from 191 individuals autopsied with detectable (HIV-D) and undetectable (HIV-U) HIV infection, and 63 age-matched controls were examined. Immunohistochemistry (IHC) was used to evaluate A[Formula: see text] plaques and neuronal p-tau, and quantitate microgliosis with markers Iba1, CD163, and CD68 in large regions of cortex. Glia in the A[Formula: see text] plaque microenvironment were quantitated by immunofluorescence (IF). The relationship of microgliosis to cognition was evaluated. No relationship between A[Formula: see text] or p-tau accumulation and overall severity of microgliosis was discerned. Individuals with uncontrolled HIV had the greatest microgliosis, but fewer A[Formula: see text] plaques; they also had higher prevalence of APOE [Formula: see text]4 alleles, but died earlier than other groups. HIV group status was the only variable predicting microgliosis over large frontal regions. In contrast, in the A[Formula: see text] plaque microenvironment, APOE [Formula: see text]4 status and sex were dominant predictors of glial infiltrates, with smaller contributions of HIV status. Cognition correlated with large-scale microgliosis in HIV-D, but not HIV-U, individuals. In this autopsy cohort, over large regions of cortex, HIV status predicts microgliosis, whereas in the A[Formula: see text] plaque microenvironment, traditional risk factors of AD (APOE [Formula: see text]4 and sex) are stronger determinants. While microgliosis does not predict neurodegenerative protein deposition, it does predict cognition in HIV-D. Increased neuroinflammation does not initiate amyloid deposition in a younger group with enhanced genetic risk. However, once A[Formula: see text] deposits are established, APOE [Formula: see text]4 predicts increased plaque-associated inflammation.
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Affiliation(s)
- Jacinta Murray
- Department of Neurology, The Icahn School of Medicine at Mount Sinai, Box 1137, Mount Sinai Medical Center, New York City, NY, 10029, USA
| | - Gregory Meloni
- Department of Neurology, The Icahn School of Medicine at Mount Sinai, Box 1137, Mount Sinai Medical Center, New York City, NY, 10029, USA
| | - Etty P Cortes
- Department of Pathology, The Icahn School of Medicine at Mount Sinai, New York City, NY, USA
| | - Ariadna KimSilva
- Department of Neurology, The Icahn School of Medicine at Mount Sinai, Box 1137, Mount Sinai Medical Center, New York City, NY, 10029, USA
| | - Michelle Jacobs
- Department of Neurology, The Icahn School of Medicine at Mount Sinai, Box 1137, Mount Sinai Medical Center, New York City, NY, 10029, USA
| | - Alyssa Ramkissoon
- Department of Neurology, The Icahn School of Medicine at Mount Sinai, Box 1137, Mount Sinai Medical Center, New York City, NY, 10029, USA
| | - John F Crary
- Department of Neuroscience, The Friedman Brain Institute, The Icahn School of Medicine at Mount Sinai, New York City, NY, USA
- Department of Artificial Intelligence and Human Health, Ronald M. Loeb Center for Alzheimer's Disease, The Icahn School of Medicine at Mount Sinai, New York City, NY, USA
- Department of Pathology, The Icahn School of Medicine at Mount Sinai, New York City, NY, USA
| | - Susan Morgello
- Department of Neurology, The Icahn School of Medicine at Mount Sinai, Box 1137, Mount Sinai Medical Center, New York City, NY, 10029, USA.
- Department of Neuroscience, The Friedman Brain Institute, The Icahn School of Medicine at Mount Sinai, New York City, NY, USA.
- Department of Pathology, The Icahn School of Medicine at Mount Sinai, New York City, NY, USA.
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23
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Infliximab and/or MESNA alleviate doxorubicin-induced Alzheimer's disease-like pathology in rats: A new insight into TNF-α/Wnt/β-catenin signaling pathway. Life Sci 2022; 301:120613. [PMID: 35523286 DOI: 10.1016/j.lfs.2022.120613] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 04/24/2022] [Accepted: 04/30/2022] [Indexed: 11/20/2022]
Abstract
AIMS The current study aimed to elucidate the neurotoxic potential of DOX to induce AD-like pathology paying attention to the role of wingless-integrated/β-catenin (Wnt/β-catenin) signaling pathway. A major aim was to evaluate the efficacy of infliximab (IFX) either individually or in combination with 2-mercaptoethane sulfonate sodium (MESNA) on the DOX-induced neurotoxicity in rats. METHODOLOGY AD-like pathology was induced in adult male Wistar rats by intraperitoneal (i.p.) administration of DOX at a dose of 3.5 mg/kg twice a week for 3 weeks. DOX-injected rats were then treated with either INF at a single dose of 5 mg/kg i.p. (IFX group), MESNA at a dose of 160 mg/kg/day i.p. for 4 weeks (MESNA group) or their combination at the same specified doses (INF + MESNA group). At the end of the study period, behavioral assessment was performed and the brain tissue samples were harvested at sacrifice. KEY FINDINGS DOX-treated rats significantly exhibited AD-like brain injury, increased amyloid burden, enhanced neuroinflammation and apoptosis, and multifocal histological injury in the cerebral cortex with widespread vacuolations. IFX and MESNA significantly reversed all the aforementioned detrimental effects in the DOX-treated rats. SIGNIFICANCE The study has provided sufficient evidence of the potential of IFX and/or MESNA to ameliorate the DOX-induced neurotoxicity, with the best improvement observed with their combined administration. A new insight has been introduced into the critical role of Wnt/β-catenin activation.
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24
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Machlovi SI, Neuner SM, Hemmer BM, Khan R, Liu Y, Huang M, Zhu JD, Castellano JM, Cai D, Marcora E, Goate AM. APOE4 confers transcriptomic and functional alterations to primary mouse microglia. Neurobiol Dis 2022; 164:105615. [PMID: 35031484 PMCID: PMC8934202 DOI: 10.1016/j.nbd.2022.105615] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 12/09/2021] [Accepted: 01/05/2022] [Indexed: 12/12/2022] Open
Abstract
Common genetic variants in more than forty loci modulate risk for Alzheimer's disease (AD). AD risk alleles are enriched within enhancers active in myeloid cells, suggesting that microglia, the brain-resident macrophages, may play a key role in the etiology of AD. A major genetic risk factor for AD is Apolipoprotein E (APOE) genotype, with the ε4/ε4 (E4) genotype increasing risk for AD by approximately 15 fold compared to the most common ε3/ε3 (E3) genotype. However, the impact of APOE genotype on microglial function has not been thoroughly investigated. To address this, we cultured primary microglia from mice in which both alleles of the mouse Apoe gene have been humanized to encode either human APOE ε3 or APOE ε4. Relative to E3 microglia, E4 microglia exhibit altered morphology, increased endolysosomal mass, increased cytokine/chemokine production, and increased lipid and lipid droplet accumulation at baseline. These changes were accompanied by decreased translation and increased phosphorylation of eIF2ɑ and eIF2ɑ-kinases that participate in the integrated stress response, suggesting that E4 genotype leads to elevated levels of cellular stress in microglia relative to E3 genotype. Using live-cell imaging and flow cytometry, we also show that E4 microglia exhibited increased phagocytic uptake of myelin and other substrates compared to E3 microglia. While transcriptomic profiling of myelin-challenged microglia revealed a largely overlapping response profile across genotypes, differential enrichment of genes in interferon signaling, extracellular matrix and translation-related pathways was identified in E4 versus E3 microglia both at baseline and following myelin challenge. Together, our results suggest E4 genotype confers several important functional alterations to microglia even prior to myelin challenge, providing insight into the molecular and cellular mechanisms by which APOE4 may increase risk for AD.
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Affiliation(s)
- Saima I Machlovi
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sarah M Neuner
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Department of Genetics and Genomic Sciences, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Brittany M Hemmer
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Riana Khan
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yiyuan Liu
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Department of Genetics and Genomic Sciences, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Min Huang
- James J Peters VA Medical Center, Research & Development, Bronx, NY, USA; Department of Neurology, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jeffrey D Zhu
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Joseph M Castellano
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Department of Neurology, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Dongming Cai
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; James J Peters VA Medical Center, Research & Development, Bronx, NY, USA; Department of Neurology, New York, NY, USA; Alzheimer Disease Research Center, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Edoardo Marcora
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Department of Genetics and Genomic Sciences, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Alison M Goate
- Ronald M. Loeb Center for Alzheimer's Disease, Nash Family Department of Neuroscience, Friedman Brain Institute, New York, NY, USA; Department of Genetics and Genomic Sciences, New York, NY, USA; Department of Neurology, New York, NY, USA; Alzheimer Disease Research Center, New York, NY, USA; Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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25
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Vink R, Corrigan F. Chronic traumatic encephalopathy: genes load the gun and repeated concussion pulls the trigger. Neural Regen Res 2022; 17:1963-1964. [PMID: 35142676 PMCID: PMC8848591 DOI: 10.4103/1673-5374.335147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Robert Vink
- Clinical and Health Sciences, University of South Australia, Adelaide, SA, Australia
| | - Frances Corrigan
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
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26
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Romero-Sevilla R, López-Espuela F, Fuentes JM, de San Juan BD, Portilla-Cuenca JC, Hijon CC, Casado-Naranjo I. Role of Inflammatory Cytokines in the Conversion of Mild Cognitive Im- pairment to Dementia: A Prospective Study. Curr Alzheimer Res 2022; 19:68-75. [PMID: 35086447 DOI: 10.2174/1567205019666220127102640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 09/13/2021] [Accepted: 10/08/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND The effect that cytokines can exert on the progression from mild cognitive impairment (MCI) to ongoing dementia is a matter of debate and the results obtained so far are controversial. OBJECTIVE The aim of the study is to analyze the influence of markers of subclinical inflammation on the progression of MCI to dementia. METHODS A prospective study involving a cohort of patients ≥ 65 years of age diagnosed with MCI and followed for 3 years was conducted. 105 patients were enrolled, and serum concentrations of several subclinical inflammatory markers were determined. RESULTS After 3.09 (2 - 3.79) years of follow-up, 47 (44.76%) patients progressed to dementia. Alpha 1-antichymotrypsin (ACT) was found to be significantly higher in patients who progressed to dementia (486.45 ± 169.18 vs. 400.91 ± 163.03; p = 0.012), and observed to significantly increase the risk of developing dementia in patients with mild cognitive impairment (1.004, 1.001-1.007; p= 0.007). IL-10 levels were significantly higher in those who remained stable (6.69 ± 18.1 vs. 32.54 ± 89.6; p = 0.04). Regarding the type of dementia to which our patients progressed, we found that patients who developed mixed dementia had higher IL-4 levels than those who converted to AD (31.54 ± 63.6 vs. 4.43 ± 12.9; p = 0.03). No significant differences were observed between the groups with regard to the ESR and LPa, CRP, IL-1 and TNF-α levels. CONCLUSION ACT levels have a significant predictive value in the conversion of MCI to dementia. IL-10 levels could be a protective factor. It is necessary to conduct studies with serial determinations of these and other inflammatory markers in order to determine their effect on the progression of MCI to dementia.
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Affiliation(s)
| | - Fidel López-Espuela
- Nursing Department. Nursing and Occupational Therapy College, University of Extremadura. Cáceres, Spain
| | - José Manuel Fuentes
- Department of Biochemistry and Molecular Biology and Genetics. Nursing and Occupational Therapy College, University of Extremadura, Cáceres, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED) Madrid, Spain
- Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE), Caceres, Spain
| | | | | | | | - Ignacio Casado-Naranjo
- Department of Neurology, Hospital Universitario de Caceres, Cáceres, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas (CIBERNED) Madrid, Spain
- Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE), Caceres, Spain
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27
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Frisoni GB, Altomare D, Thal DR, Ribaldi F, van der Kant R, Ossenkoppele R, Blennow K, Cummings J, van Duijn C, Nilsson PM, Dietrich PY, Scheltens P, Dubois B. The probabilistic model of Alzheimer disease: the amyloid hypothesis revised. Nat Rev Neurosci 2022; 23:53-66. [PMID: 34815562 PMCID: PMC8840505 DOI: 10.1038/s41583-021-00533-w] [Citation(s) in RCA: 183] [Impact Index Per Article: 91.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2021] [Indexed: 01/03/2023]
Abstract
The current conceptualization of Alzheimer disease (AD) is driven by the amyloid hypothesis, in which a deterministic chain of events leads from amyloid deposition and then tau deposition to neurodegeneration and progressive cognitive impairment. This model fits autosomal dominant AD but is less applicable to sporadic AD. Owing to emerging information regarding the complex biology of AD and the challenges of developing amyloid-targeting drugs, the amyloid hypothesis needs to be reconsidered. Here we propose a probabilistic model of AD in which three variants of AD (autosomal dominant AD, APOE ε4-related sporadic AD and APOE ε4-unrelated sporadic AD) feature decreasing penetrance and decreasing weight of the amyloid pathophysiological cascade, and increasing weight of stochastic factors (environmental exposures and lower-risk genes). Together, these variants account for a large share of the neuropathological and clinical variability observed in people with AD. The implementation of this model in research might lead to a better understanding of disease pathophysiology, a revision of the current clinical taxonomy and accelerated development of strategies to prevent and treat AD.
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Affiliation(s)
- Giovanni B. Frisoni
- Laboratory of Neuroimaging of Aging (LANVIE), University of Geneva, Geneva, Switzerland.,Memory Clinic, Geneva University Hospitals, Geneva, Switzerland.,
| | - Daniele Altomare
- Laboratory of Neuroimaging of Aging (LANVIE), University of Geneva, Geneva, Switzerland.,Memory Clinic, Geneva University Hospitals, Geneva, Switzerland
| | - Dietmar Rudolf Thal
- Laboratory for Neuropathology, Department of Imaging and Pathology, and Leuven Brain Institute, University of Leuven, Leuven, Belgium.,Department of Pathology, University Hospital Leuven, Leuven, Belgium
| | - Federica Ribaldi
- Laboratory of Neuroimaging of Aging (LANVIE), University of Geneva, Geneva, Switzerland.,Memory Clinic, Geneva University Hospitals, Geneva, Switzerland.,Laboratory of Alzheimer’s Neuroimaging and Epidemiology (LANE), IRCCS Centro S. Giovanni di Dio Fatebenefratelli, Brescia, Italy.,Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Rik van der Kant
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, Netherlands.,Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, Netherlands
| | - Rik Ossenkoppele
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, Netherlands.,Clinical Memory Research Unit, Lund University, Lund, Sweden
| | - Kaj Blennow
- Cinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Jeffrey Cummings
- Chambers-Grundy Center for Transformative Neuroscience, Department of Brain Health, School of Integrated Health Sciences; University of Nevada, Las Vegas, Las Vegas, NV, USA
| | - Cornelia van Duijn
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, Netherlands.,Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Peter M. Nilsson
- Department of Clinical Sciences, Lund University, Skåne University Hospital, Malmö, Sweden
| | | | - Philip Scheltens
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Amsterdam, Netherlands.,Life Science Partners, Amsterdam, Netherlands
| | - Bruno Dubois
- Institut de la Mémoire et de la Maladie d’Alzheimer, IM2A, Groupe Hospitalier Pitié-Salpêtrière, Sorbonne Université, Paris, France.,Institut du Cerveau et de la Moelle Épinière, UMR-S975, INSERM, Paris, France
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Jeremic D, Jiménez-Díaz L, Navarro-López JD. Past, present and future of therapeutic strategies against amyloid-β peptides in Alzheimer's disease: a systematic review. Ageing Res Rev 2021; 72:101496. [PMID: 34687956 DOI: 10.1016/j.arr.2021.101496] [Citation(s) in RCA: 116] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 09/30/2021] [Accepted: 10/18/2021] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease in ageing, affecting around 46 million people worldwide but few treatments are currently available. The etiology of AD is still puzzling, and new drugs development and clinical trials have high failure rates. Urgent outline of an integral (multi-target) and effective treatment of AD is needed. Accumulation of amyloid-β (Aβ) peptides is considered one of the fundamental neuropathological pillars of the disease, and its dyshomeostasis has shown a crucial role in AD onset. Therefore, many amyloid-targeted therapies have been investigated. Here, we will systematically review recent (from 2014) investigational, follow-up and review studies focused on anti-amyloid strategies to summarize and analyze their current clinical potential. Combination of anti-Aβ therapies with new developing early detection biomarkers and other therapeutic agents acting on early functional AD changes will be highlighted in this review. Near-term approval seems likely for several drugs acting against Aβ, with recent FDA approval of a monoclonal anti-Aβ oligomers antibody -aducanumab- raising hopes and controversies. We conclude that, development of oligomer-epitope specific Aβ treatment and implementation of multiple improved biomarkers and risk prediction methods allowing early detection, together with therapies acting on other factors such as hyperexcitability in early AD, could be the key to slowing this global pandemic.
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29
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Kloske CM, Dugan AJ, Weekman EM, Winder Z, Patel E, Nelson PT, Fardo DW, Wilcock DM. Inflammatory Pathways Are Impaired in Alzheimer Disease and Differentially Associated With Apolipoprotein E Status. J Neuropathol Exp Neurol 2021; 80:922-932. [PMID: 34486652 PMCID: PMC8557334 DOI: 10.1093/jnen/nlab085] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Alzheimer disease (AD) is a neurodegenerative disease characterized by a cognitive decline leading to dementia. The most impactful genetic risk factor is apolipoprotein E (APOE). APOE-ε4 significantly increases AD risk, APOE-ε3 is the most common gene variant, and APOE-ε2 protects against AD. However, the underlying mechanisms of APOE-ε4 on AD risk remains unclear, with APOE-ε4 impacting many pathways. We investigated how the APOE isoforms associated with the neuroinflammatory state of the brain with and without AD pathology. Frozen brain tissue from the superior and middle temporal gyrus was analyzed from APOE-ε3/3 (n = 9) or APOE-ε4/4 (n = 10) participants with AD pathology and APOE-ε3/3 (n = 9) participants without AD pathology. We determined transcript levels of 757 inflammatory related genes using the NanoString Human Neuroinflammation Panel. We found significant pathways impaired in APOE-ε4/4-AD individuals compared to APOE-ε3/3-AD. Of interest, expression of genes related to microglial activation (SALL1), motility (FSCN1), epigenetics (DNMT1), and others showed altered expression. Additionally, we performed immunohistochemistry of P2RY12 to confirm reduced microglial activation. Our results suggest APOE-ε3 responds to AD pathology while potentially having a harmful long-term inflammatory response, while APOE-ε4 shows a weakened response to pathology. Overall, APOE isoforms appear to modulate the brain immune response to AD-type pathology.
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Affiliation(s)
- Courtney M Kloske
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Adam J Dugan
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Erica M Weekman
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Zachary Winder
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Ela Patel
- Department of Pathology and Laboratory Medicine, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Peter T Nelson
- Department of Pathology and Laboratory Medicine, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - David W Fardo
- Department of Biostatics, Sanders-Brown Center on Aging, College of Public Health, University of Kentucky, Lexington, Kentucky, USA
| | - Donna M Wilcock
- From the Department of Physiology, Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
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30
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Koutsodendris N, Nelson MR, Rao A, Huang Y. Apolipoprotein E and Alzheimer's Disease: Findings, Hypotheses, and Potential Mechanisms. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2021; 17:73-99. [PMID: 34460318 DOI: 10.1146/annurev-pathmechdis-030421-112756] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder that involves dysregulation of many cellular and molecular processes. It is notoriously difficult to develop therapeutics for AD due to its complex nature. Nevertheless, recent advancements in imaging technology and the development of innovative experimental techniques have allowed researchers to perform in-depth analyses to uncover the pathogenic mechanisms of AD. An important consideration when studying late-onset AD is its major genetic risk factor, apolipoprotein E4 (apoE4). Although the exact mechanisms underlying apoE4 effects on AD initiation and progression are not fully understood, recent studies have revealed critical insights into the apoE4-induced deficits that occur in AD. In this review, we highlight notable studies that detail apoE4 effects on prominent AD pathologies, including amyloid-β, tau pathology, neuroinflammation, and neural network dysfunction. We also discuss evidence that defines the physiological functions of apoE and outlines how these functions are disrupted in apoE4-related AD. Expected final online publication date for the Annual Review of Pathology: Mechanisms of Disease, Volume 17 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Nicole Koutsodendris
- Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, California 94131, USA; , .,Gladstone Institutes of Neurological Disease, San Francisco, California 94158, USA
| | - Maxine R Nelson
- Gladstone Institutes of Neurological Disease, San Francisco, California 94158, USA.,Biomedical Sciences Graduate Program, University of California, San Francisco, California 94143, USA
| | - Antara Rao
- Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, California 94131, USA; , .,Gladstone Institutes of Neurological Disease, San Francisco, California 94158, USA
| | - Yadong Huang
- Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, California 94131, USA; , .,Gladstone Institutes of Neurological Disease, San Francisco, California 94158, USA.,Biomedical Sciences Graduate Program, University of California, San Francisco, California 94143, USA.,Department of Neurology, University of California, San Francisco, California 94158, USA
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31
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Pashaei Y. Drug repurposing of selective serotonin reuptake inhibitors: Could these drugs help fight COVID-19 and save lives? J Clin Neurosci 2021; 88:163-172. [PMID: 33992179 PMCID: PMC7973060 DOI: 10.1016/j.jocn.2021.03.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 03/05/2021] [Accepted: 03/11/2021] [Indexed: 02/09/2023]
Abstract
The current 2019 novel coronavirus disease (COVID-19), an emerging infectious disease, is undoubtedly the most challenging pandemic in the 21st century. A total of 92,977,768 confirmed cases of COVID-19 and 1,991,289 deaths were reported globally up to January 14, 2021. COVID-19 also affects people's mental health and quality of life. At present, there is no effective therapeutic strategy for the management of this disease. Therefore, in the absence of a specific vaccine or curative treatment, it is an urgent need to identify safe, effective and globally available drugs for reducing COVID-19 morbidity and fatalities. In this review, we focus on selective serotonin reuptake inhibitors (SSRIs: a class of antidepressant drugs with widespread availability and an optimal tolerability profile) that can potentially be repurposed for COVID-19 and are currently being tested in clinical trials. We also summarize the existing literature on what is known about the link between serotonin (5-HT) and the immune system. From the evidence reviewed here, we propose fluoxetine as an adjuvant therapeutic agent for COVID-19 based on its known immunomodulatory, anti-inflammatory and antiviral properties. Fluoxetine may potentially reduce pro-inflammatory chemokine/cytokines levels (such as CCL-2, IL-6, and TNF-α) in COVID-19 patients. Furthermore, fluoxetine may help to attenuate neurological complications of COVID-19.
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32
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Precision Nutrition for Alzheimer's Prevention in ApoE4 Carriers. Nutrients 2021; 13:nu13041362. [PMID: 33921683 PMCID: PMC8073598 DOI: 10.3390/nu13041362] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/13/2021] [Accepted: 04/16/2021] [Indexed: 12/14/2022] Open
Abstract
The ApoE4 allele is the most well-studied genetic risk factor for Alzheimer’s disease, a condition that is increasing in prevalence and remains without a cure. Precision nutrition targeting metabolic pathways altered by ApoE4 provides a tool for the potential prevention of disease. However, no long-term human studies have been conducted to determine effective nutritional protocols for the prevention of Alzheimer’s disease in ApoE4 carriers. This may be because relatively little is yet known about the precise mechanisms by which the genetic variant confers an increased risk of dementia. Fortunately, recent research is beginning to shine a spotlight on these mechanisms. These new data open up the opportunity for speculation as to how carriers might ameliorate risk through lifestyle and nutrition. Herein, we review recent discoveries about how ApoE4 differentially impacts microglia and inflammatory pathways, astrocytes and lipid metabolism, pericytes and blood–brain barrier integrity, and insulin resistance and glucose metabolism. We use these data as a basis to speculate a precision nutrition approach for ApoE4 carriers, including a low-glycemic index diet with a ketogenic option, specific Mediterranean-style food choices, and a panel of seven nutritional supplements. Where possible, we integrate basic scientific mechanisms with human observational studies to create a more complete and convincing rationale for this precision nutrition approach. Until recent research discoveries can be translated into long-term human studies, a mechanism-informed practical clinical approach may be useful for clinicians and patients with ApoE4 to adopt a lifestyle and nutrition plan geared towards Alzheimer’s risk reduction.
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33
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Wang S, Li B, Solomon V, Fonteh A, Rapoport SI, Bennett DA, Arvanitakis Z, Chui HC, Miller C, Sullivan PM, Wang HY, Yassine HN. Calcium-dependent cytosolic phospholipase A 2 activation is implicated in neuroinflammation and oxidative stress associated with ApoE4. Mol Neurodegener 2021; 16:26. [PMID: 33863362 PMCID: PMC8052701 DOI: 10.1186/s13024-021-00438-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 03/03/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Apolipoprotein E4 (APOE4) is associated with a greater response to neuroinflammation and the risk of developing late-onset Alzheimer's disease (AD), but the mechanisms for this association are not clear. The activation of calcium-dependent cytosolic phospholipase A2 (cPLA2) is involved in inflammatory signaling and is elevated within the plaques of AD brains. The relation between APOE4 genotype and cPLA2 activity is not known. METHODS Mouse primary astrocytes, mouse and human brain samples differing by APOE genotypes were collected for measuring cPLA2 expression, phosphorylation, and activity in relation to measures of inflammation and oxidative stress. RESULTS Greater cPLA2 phosphorylation, cPLA2 activity and leukotriene B4 (LTB4) levels were identified in ApoE4 compared to ApoE3 in primary astrocytes, brains of ApoE-targeted replacement (ApoE-TR) mice, and in human brain homogenates from the inferior frontal cortex of patients with AD carrying APOE3/E4 compared to APOE3/E3. Greater cPLA2 phosphorylation was also observed in human postmortem frontal cortical synaptosomes and primary astrocytes after treatment with recombinant ApoE4 ex vivo. In ApoE4 astrocytes, the greater levels of LTB4, reactive oxygen species (ROS), and inducible nitric oxide synthase (iNOS) were reduced after cPLA2 inhibition. CONCLUSIONS Our findings implicate greater activation of cPLA2 signaling system with APOE4, which could represent a potential drug target for mitigating the increased neuroinflammation with APOE4 and AD.
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Affiliation(s)
- Shaowei Wang
- Departments of Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Boyang Li
- Departments of Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Victoria Solomon
- Departments of Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Alfred Fonteh
- Huntington Medical Research Institutes, Pasadena, CA USA
| | | | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL USA
| | - Zoe Arvanitakis
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL USA
| | - Helena C. Chui
- Departments of Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Carol Miller
- Departments of Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA USA
| | - Patrick M. Sullivan
- Department of Medicine, Duke University Medical Center, Durham Veterans Health Administration Medical Center’s Geriatric Research, Education and Clinical Center, Durham, NC USA
| | - Hoau-Yan Wang
- The City University of New York School of Medicine, New York, NY USA
- Graduate School of The City University of New York, New York, USA
| | - Hussein N. Yassine
- Departments of Medicine and Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA USA
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34
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Chen Y, Hong T, Chen F, Sun Y, Wang Y, Cui L. Interplay Between Microglia and Alzheimer's Disease-Focus on the Most Relevant Risks: APOE Genotype, Sex and Age. Front Aging Neurosci 2021; 13:631827. [PMID: 33897406 PMCID: PMC8060487 DOI: 10.3389/fnagi.2021.631827] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 03/18/2021] [Indexed: 12/20/2022] Open
Abstract
As the main immune cells of the central nervous system (CNS), microglia regulates normal development, homeostasis and general brain physiology. These functions put microglia at the forefront of CNS repair and recovery. Uncontrolled activation of microglia is related to the course of neurodegenerative diseases such as Alzheimer’s disease. It is clear that the classic pathologies of amyloid β (Aβ) and Tau are usually accompanied by the activation of microglia, and the activation of microglia also serves as an early event in the pathogenesis of AD. Therefore, during the occurrence and development of AD, the key susceptibility factors for AD—apolipoprotein E (APOE) genotype, sex and age—may further interact with microglia to exacerbate neurodegeneration. In this review, we discuss the role of microglia in the progression of AD related to the three risk factors for AD: APOE genotype, sex and aging. APOE-expressing microglia accumulates around Aβ plaques, and the presence of APOE4 may disrupt the phagocytosis of Aβ aggregates and aggravate neurodegeneration in Tau disease models. In addition, females have a high incidence of AD, and normal female microglia and estrogen have protective effects under normal conditions. However, under the influence of AD, female microglia seem to lose their protective effect and instead accelerate the course of AD. Aging, another major risk factor, may increase the sensitivity of microglia, leading to the exacerbation of microglial dysfunction in elderly AD. Obviously, in the role of microglia in AD, the three main risk factors of APOE, sex, and aging are not independent and have synergistic effects that contribute to the risk of AD. Moreover, new microglia can replace dysfunctional microglia after microglial depletion, which is a new promising strategy for AD treatment.
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Affiliation(s)
- Yanting Chen
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Tingting Hong
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Feng Chen
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yuanhong Sun
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Yan Wang
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Lili Cui
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
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35
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Song L, Wells EA, Robinson AS. Critical Molecular and Cellular Contributors to Tau Pathology. Biomedicines 2021; 9:biomedicines9020190. [PMID: 33672982 PMCID: PMC7918468 DOI: 10.3390/biomedicines9020190] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/07/2021] [Accepted: 02/11/2021] [Indexed: 12/11/2022] Open
Abstract
Tauopathies represent a group of neurodegenerative diseases including Alzheimer's disease (AD) that are characterized by the deposition of filamentous tau aggregates in the brain. The pathogenesis of tauopathies starts from the formation of toxic 'tau seeds' from hyperphosphorylated tau monomers. The presence of specific phosphorylation sites and heat shock protein 90 facilitates soluble tau protein aggregation. Transcellular propagation of pathogenic tau into synaptically connected neuronal cells or adjacent glial cells via receptor-mediated endocytosis facilitate disease spread through the brain. While neuroprotective effects of glial cells-including phagocytotic microglial and astroglial phenotypes-have been observed at the early stage of neurodegeneration, dysfunctional neuronal-glial cellular communication results in a series of further pathological consequences as the disease progresses, including abnormal axonal transport, synaptic degeneration, and neuronal loss, accompanied by a pro-inflammatory microenvironment. Additionally, the discovery of microtubule-associated protein tau (MAPT) gene mutations and the strongest genetic risk factor of tauopathies-an increase in the presence of the ε2 allele of apolipoprotein E (ApoE)-provide important clues to understanding tau pathology progression. In this review, we describe the crucial signaling pathways and diverse cellular contributors to the progression of tauopathies. A systematic understanding of disease pathogenesis provides novel insights into therapeutic targets within altered signaling pathways and is of great significance for discovering effective treatments for tauopathies.
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36
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Lee JY, Marian OC, Don AS. Defective Lysosomal Lipid Catabolism as a Common Pathogenic Mechanism for Dementia. Neuromolecular Med 2021; 23:1-24. [PMID: 33550528 DOI: 10.1007/s12017-021-08644-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/11/2021] [Indexed: 02/06/2023]
Abstract
Dementia poses an ever-growing burden to health care and social services as life expectancies have grown across the world and populations age. The most common forms of dementia are Alzheimer's disease (AD), vascular dementia, frontotemporal dementia (FTD), and Lewy body dementia, which includes Parkinson's disease (PD) dementia and dementia with Lewy bodies (DLB). Genomic studies over the past 3 decades have identified variants in genes regulating lipid transporters and endosomal processes as major risk determinants for AD, with the most significant being inheritance of the ε4 allele of the APOE gene, encoding apolipoprotein E. A recent surge in research on lipid handling and metabolism in glia and neurons has established defective lipid clearance from endolysosomes as a central driver of AD pathogenesis. The most prevalent genetic risk factors for DLB are the APOE ε4 allele, and heterozygous loss of function mutations in the GBA gene, encoding the lysosomal catabolic enzyme glucocerebrosidase; whilst heterozygous mutations in the GRN gene, required for lysosomal catabolism of sphingolipids, are responsible for a significant proportion of FTD cases. Homozygous mutations in the GBA or GRN genes produce the lysosomal storage diseases Gaucher disease and neuronal ceroid lipofuscinosis. Research from mouse and cell culture models, and neuropathological evidence from lysosomal storage diseases, has established that impaired cholesterol or sphingolipid catabolism is sufficient to produce the pathological hallmarks of dementia, indicating that defective lipid catabolism is a common mechanism in the etiology of dementia.
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Affiliation(s)
- Jun Yup Lee
- Centenary Institute, The University of Sydney, Camperdown, NSW, 2006, Australia
| | - Oana C Marian
- Centenary Institute, The University of Sydney, Camperdown, NSW, 2006, Australia
| | - Anthony S Don
- Centenary Institute, The University of Sydney, Camperdown, NSW, 2006, Australia. .,NHMRC Clinical Trials Centre, The University of Sydney, Camperdown, NSW, 2006, Australia.
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37
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Kulczyńska-Przybik A, Słowik A, Mroczko P, Borawski B, Groblewska M, Borawska R, Mroczko B. Cerebrospinal Fluid and Blood CX3CL1 as a Potential Biomarker in Early Diagnosis and Prognosis of Dementia. Curr Alzheimer Res 2020; 17:709-721. [PMID: 33167838 DOI: 10.2174/1567205017666201109095657] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 09/11/2020] [Accepted: 10/13/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND A growing body of evidence highlights the crucial role of neuroinflammation and chemokine involvement in cognitive impairment pathophysiology. Fractalkine (CX3CL1) appears to be a relevant causative factor in the development of dementia, particularly at the early stages of the disease. However, limited data are available on the levels of CX3CL1 in the cerebrospinal fluid (CSF) and blood. Additionally, to date, its utility as a biomarker for MCI or AD has not been studied. OBJECTIVE The aim of the present study was to evaluate the clinical utility of CX3CL1 in the early diagnosis of cognitive impairment. We also compared the diagnostic usefulness of CX3CL1 with other biomarkers associated with neuroinflammation. METHODS A total of 60 patients with cognitive impairment, including 42 patients with AD and 18 subjects with MCI, as well as 20 cognitively healthy controls were enrolled in the study. CSF and blood concentrations of CX3CL1, CCL-2, and YKL-40 were measured by ELISA. RESULTS Significantly higher CSF and blood concentrations of CX3CL1 were observed in MCI and AD patients compared to older individuals without cognitive impairment. The increase in the levels of CX3CL1 and YKL-40 in non-demented subjects was associated with MCI. The area under the ROC curve for CX3CL1 in MCI subjects was larger in comparison to classical AD markers. CONCLUSION Presented results indicate a crucial role of CX3CL1 in the pathology of cognitive impairment and the potential usefulness of this protein in the early diagnosis of MCI and AD.
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Affiliation(s)
| | - Agnieszka Słowik
- Department of Neurology, Jagiellonian University, Krakow, Poland
| | - Piotr Mroczko
- Department of Criminal Law and Criminology, Faculty of Law, University of Bialystok, Bialystok, Poland
| | - Bartłomiej Borawski
- Department of Neurodegeneration Diagnostics, Medical University of Bialystok, Waszyngtona, Bialystok, Poland
| | - Magdalena Groblewska
- Department of Biochemical Diagnostics, University Hospital in Bialystok, Bialystok, Poland
| | - Renata Borawska
- Department of Neurodegeneration Diagnostics, Medical University of Bialystok, Waszyngtona, Bialystok, Poland
| | - Barbara Mroczko
- Department of Neurodegeneration Diagnostics, Medical University of Bialystok, Waszyngtona, Bialystok, Poland.,Department of Biochemical Diagnostics, University Hospital in Bialystok, Bialystok, Poland.,Department of Biochemical Diagnostics, Medical University of Bialystok, Bialystok, Poland
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38
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Ennerfelt HE, Lukens JR. The role of innate immunity in Alzheimer's disease. Immunol Rev 2020; 297:225-246. [PMID: 32588460 PMCID: PMC7783860 DOI: 10.1111/imr.12896] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 05/23/2020] [Accepted: 05/28/2020] [Indexed: 12/12/2022]
Abstract
The amyloid hypothesis has dominated Alzheimer's disease (AD) research for almost 30 years. This hypothesis hinges on the predominant clinical role of the amyloid beta (Aβ) peptide in propagating neurofibrillary tangles (NFTs) and eventual cognitive impairment in AD. Recent research in the AD field has identified the brain-resident macrophages, known as microglia, and their receptors as integral regulators of both the initiation and propagation of inflammation, Aβ accumulation, neuronal loss, and memory decline in AD. Emerging studies have also begun to reveal critical roles for distinct innate immune pathways in AD pathogenesis, which has led to great interest in harnessing the innate immune response as a therapeutic strategy to treat AD. In this review, we will highlight recent advancements in our understanding of innate immunity and inflammation in AD onset and progression. Additionally, there has been mounting evidence suggesting pivotal contributions of environmental factors and lifestyle choices in AD pathogenesis. Therefore, we will also discuss recent findings, suggesting that many of these AD risk factors influence AD progression via modulation of microglia and immune responses.
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Affiliation(s)
- Hannah E. Ennerfelt
- Center for Brain Immunology and Glia (BIG), Department of Neuroscience, University of Virginia, Charlottesville, VA 22908, USA
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA 22908, USA
- Cell and Molecular Biology Training Program, School of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - John R. Lukens
- Center for Brain Immunology and Glia (BIG), Department of Neuroscience, University of Virginia, Charlottesville, VA 22908, USA
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA 22908, USA
- Cell and Molecular Biology Training Program, School of Medicine, University of Virginia, Charlottesville, VA 22908, USA
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