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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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Adeniyi PA, Gong X, MacGregor E, Degener-O’Brien K, McClendon E, Garcia M, Romero O, Russell J, Srivastava T, Miller J, Keene CD, Back SA. Ferroptosis of Microglia in Aging Human White Matter Injury. Ann Neurol 2023; 94:1048-1066. [PMID: 37605362 PMCID: PMC10840747 DOI: 10.1002/ana.26770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/07/2023] [Accepted: 08/14/2023] [Indexed: 08/23/2023]
Abstract
OBJECTIVE Because the role of white matter (WM) degenerating microglia (DM) in remyelination failure is unclear, we sought to define the core features of this novel population of aging human microglia. METHODS We analyzed postmortem human brain tissue to define a population of DM in aging WM lesions. We used immunofluorescence staining and gene expression analysis to investigate molecular mechanisms related to the degeneration of DM. RESULTS We found that DM, which accumulated myelin debris were selectively enriched in the iron-binding protein light chain ferritin, and accumulated PLIN2-labeled lipid droplets. DM displayed lipid peroxidation injury and enhanced expression for TOM20, a mitochondrial translocase, and a sensor of oxidative stress. DM also displayed enhanced expression of the DNA fragmentation marker phospho-histone H2A.X. We identified a unique set of ferroptosis-related genes involving iron-mediated lipid dysmetabolism and oxidative stress that were preferentially expressed in WM injury relative to gray matter neurodegeneration. INTERPRETATION Ferroptosis appears to be a major mechanism of WM injury in Alzheimer's disease and vascular dementia. WM DM are a novel therapeutic target to potentially reduce the impact of WM injury and myelin loss on the progression of cognitive impairment. ANN NEUROL 2023;94:1048-1066.
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Affiliation(s)
- Philip A. Adeniyi
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Xi Gong
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Ellie MacGregor
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Kiera Degener-O’Brien
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Evelyn McClendon
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Mariel Garcia
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Oscar Romero
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Joshua Russell
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Taasin Srivastava
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
| | - Jeremy Miller
- Allen Institute for Brain Science, Seattle, Washington, USA
| | - C. Dirk Keene
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Stephen A. Back
- Departments of Pediatrics and, Oregon Health & Science University, Portland, Oregon, USA
- Neurology, Oregon Health & Science University, Portland, Oregon, USA
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Noh B, Blasco‐Conesa MP, Rahman SM, Monga S, Ritzel R, Guzman G, Lai Y, Ganesh BP, Urayama A, McCullough LD, Moruno‐Manchon JF. Iron overload induces cerebral endothelial senescence in aged mice and in primary culture in a sex-dependent manner. Aging Cell 2023; 22:e13977. [PMID: 37675802 PMCID: PMC10652299 DOI: 10.1111/acel.13977] [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: 04/12/2023] [Revised: 08/13/2023] [Accepted: 08/16/2023] [Indexed: 09/08/2023] Open
Abstract
Iron imbalance in the brain negatively affects brain function. With aging, iron levels increase in the brain and contribute to brain damage and neurological disorders. Changes in the cerebral vasculature with aging may enhance iron entry into the brain parenchyma, leading to iron overload and its deleterious consequences. Endothelial senescence has emerged as an important contributor to age-related changes in the cerebral vasculature. Evidence indicates that iron overload may induce senescence in cultured cell lines. Importantly, cells derived from female human and mice generally show enhanced senescence-associated phenotype, compared with males. Thus, we hypothesize that cerebral endothelial cells (CEC) derived from aged female mice are more susceptible to iron-induced senescence, compared with CEC from aged males. We found that aged female mice, but not males, showed cognitive deficits when chronically treated with ferric citrate (FC), and their brains and the brain vasculature showed senescence-associated phenotype. We also found that primary culture of CEC derived from aged female mice, but not male-derived CEC, exhibited senescence-associated phenotype when treated with FC. We identified that the transmembrane receptor Robo4 was downregulated in the brain vasculature and in cultured primary CEC derived from aged female mice, compared with those from male mice. We discovered that Robo4 downregulation contributed to enhanced vulnerability to FC-induced senescence. Thus, our study identifies Robo4 downregulation as a driver of senescence induced by iron overload in primary culture of CEC and a potential risk factor of brain vasculature impairment and brain dysfunction.
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Affiliation(s)
- Brian Noh
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Maria Pilar Blasco‐Conesa
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Syed Mushfiqur Rahman
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Sheelu Monga
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Rodney Ritzel
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Gary Guzman
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Yun‐Ju Lai
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
- Solomont School of NursingZuckerberg College of Health SciencesUniversity of Massachusetts LowellLowellMassachusettsUSA
| | - Bhanu Priya Ganesh
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Akihiko Urayama
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Louise D. McCullough
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
| | - Jose Felix Moruno‐Manchon
- Department of NeurologyMcGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTexasUSA
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Liu Y, Yang W, Xue J, Chen J, Liu S, Zhang S, Zhang X, Gu X, Dong Y, Qiu P. Neuroinflammation: The central enabler of postoperative cognitive dysfunction. Biomed Pharmacother 2023; 167:115582. [PMID: 37748409 DOI: 10.1016/j.biopha.2023.115582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 09/27/2023] Open
Abstract
The proportion of advanced age patients undergoing surgical procedures is on the rise owing to advancements in surgical and anesthesia technologies as well as an overall aging population. As a complication of anesthesia and surgery, older patients frequently suffer from postoperative cognitive dysfunction (POCD), which may persist for weeks, months or even longer. POCD is a complex pathological process involving multiple pathogenic factors, and its mechanism is yet unclear. Potential theories include inflammation, deposition of pathogenic proteins, imbalance of neurotransmitters, and chronic stress. The identification, prevention, and treatment of POCD are still in the exploratory stages owing to the absence of standardized diagnostic criteria. Undoubtedly, comprehending the development of POCD remains crucial in overcoming the illness. Neuroinflammation is the leading hypothesis and a crucial component of the pathological network of POCD and may have complex interactions with other mechanisms. In this review, we discuss the possible ways in which surgery and anesthesia cause neuroinflammation and investigate the connection between neuroinflammation and the development of POCD. Understanding these mechanisms may likely ensure that future treatment options of POCD are more effective.
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Affiliation(s)
- Yang Liu
- Department of Oncology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning province, China
| | - Wei Yang
- Department of Infectious Disease, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning province, China
| | - Jinqi Xue
- Department of Oncology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning province, China
| | - Juntong Chen
- Zhejiang University School of Medicine, Hangzhou 311121, Zhejiang province, China
| | - Shiqing Liu
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
| | - Shijie Zhang
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
| | - Xiaohui Zhang
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
| | - Xi Gu
- Department of Oncology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning province, China.
| | - Youjing Dong
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China.
| | - Peng Qiu
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China.
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Lau V, Ramer L, Tremblay MÈ. An aging, pathology burden, and glial senescence build-up hypothesis for late onset Alzheimer's disease. Nat Commun 2023; 14:1670. [PMID: 36966157 PMCID: PMC10039917 DOI: 10.1038/s41467-023-37304-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 03/07/2023] [Indexed: 03/27/2023] Open
Abstract
Alzheimer's disease (AD) predominantly occurs as a late onset (LOAD) form involving neurodegeneration and cognitive decline with progressive memory loss. Risk factors that include aging promote accumulation of AD pathologies, such as amyloid-beta and tau aggregates, as well as inflammation and oxidative stress. Homeostatic glial states regulate and suppress pathology buildup; inflammatory states exacerbate pathology by releasing pro-inflammatory cytokines. Multiple stresses likely induce glial senescence, which could decrease supportive functions and reinforce inflammation. In this perspective, we hypothesize that aging first drives AD pathology burden, whereafter AD pathology putatively induces glial senescence in LOAD. We hypothesize that increasing glial senescence, particularly local senescent microglia accumulation, sustains and drives perpetuating buildup and spread of AD pathologies, glial aging, and further senescence. We predict that increasing glial senescence, particularly local senescent microglia accumulation, also transitions individuals from healthy cognition into mild cognitive impairment and LOAD diagnosis. These pathophysiological underpinnings may centrally contribute to LOAD onset, but require further mechanistic investigation.
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Affiliation(s)
- Victor Lau
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
| | - Leanne Ramer
- Department of Biomedical Physiology & Kinesiology, Simon Fraser University, Burnaby, BC, Canada.
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
- Axe Neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada.
- Département de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec, QC, Canada.
- The Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada.
- Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada.
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Vielee ST, Wise JP. Among Gerontogens, Heavy Metals Are a Class of Their Own: A Review of the Evidence for Cellular Senescence. Brain Sci 2023; 13:500. [PMID: 36979310 PMCID: PMC10046019 DOI: 10.3390/brainsci13030500] [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: 02/07/2023] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 03/18/2023] Open
Abstract
Advancements in modern medicine have improved the quality of life across the globe and increased the average lifespan of our population by multiple decades. Current estimates predict by 2030, 12% of the global population will reach a geriatric age and live another 3-4 decades. This swelling geriatric population will place critical stress on healthcare infrastructures due to accompanying increases in age-related diseases and comorbidities. While much research focused on long-lived individuals seeks to answer questions regarding how to age healthier, there is a deficit in research investigating what aspects of our lives accelerate or exacerbate aging. In particular, heavy metals are recognized as a significant threat to human health with links to a plethora of age-related diseases, and have widespread human exposures from occupational, medical, or environmental settings. We believe heavy metals ought to be classified as a class of gerontogens (i.e., chemicals that accelerate biological aging in cells and tissues). Gerontogens may be best studied through their effects on the "Hallmarks of Aging", nine physiological hallmarks demonstrated to occur in aged cells, tissues, and bodies. Evidence suggests that cellular senescence-a permanent growth arrest in cells-is one of the most pertinent hallmarks of aging and is a useful indicator of aging in tissues. Here, we discuss the roles of heavy metals in brain aging. We briefly discuss brain aging in general, then expand upon observations for heavy metals contributing to age-related neurodegenerative disorders. We particularly emphasize the roles and observations of cellular senescence in neurodegenerative diseases. Finally, we discuss the observations for heavy metals inducing cellular senescence. The glaring lack of knowledge about gerontogens and gerontogenic mechanisms necessitates greater research in the field, especially in the context of the global aging crisis.
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Affiliation(s)
- Samuel T. Vielee
- Pediatrics Research Institute, Department of Pediatrics, University of Louisville, Louisville, KY 40202, USA
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40202, USA
| | - John P. Wise
- Pediatrics Research Institute, Department of Pediatrics, University of Louisville, Louisville, KY 40202, USA
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40202, USA
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7
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Neumann P, Lenz DE, Streit WJ, Bechmann I. Is microglial dystrophy a form of cellular senescence? An analysis of senescence markers in the aged human brain. Glia 2023; 71:377-390. [PMID: 36286188 DOI: 10.1002/glia.24282] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/27/2022] [Accepted: 09/30/2022] [Indexed: 01/08/2023]
Abstract
Aging can cause morphological transformation in human microglia indicative of cell senescence, termed microglial dystrophy. However, cellular senescence is characterized by additional changes, such as an irregular cell cycle arrest, and a variety of metabolic and molecular changes including a senescence-associated secretory phenotype, dysfunction of degradation mechanisms, and altered DNA damage response. Here, we tested whether dystrophic microglia display customary markers of cell senescence by performing double and triple staining in sections of the temporal lobe and brain stem from 14 humans. We found that markers related to oxidative damage, such as upregulation of 8-hydroxy-2'-deoxyguanosine (8-OHdG), hemeoxygenase-1 (HO-1), and y-H2AX, as well as inclusion of lipofuscin, do not or only exceptionally colocalize with dystrophic microglia. Further, we did not observe a decline in lamin B1 around nuclear laminae in either dystrophic or ramified microglia within the same microscopic field. Only ferritin expression, which is known to increase with aging in CNS microglia, was frequently observed in dystrophic, but rarely in ramified microglial cells. We conclude that neither dystrophic nor ramified microglia in human brain exhibit significant expression of conventional senescence markers associated with oxidative stress, and that ferritin is the dominant immunophenotypic change related to microglial aging. We suggest that multiple pathogenic mechanisms other than those driving cellular senescence contribute to dystrophic transformation of microglia.
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Affiliation(s)
| | - Dana E Lenz
- Institute of Anatomy, Universität Leipzig, Leipzig, Germany
| | - Wolfgang J Streit
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Ingo Bechmann
- Institute of Anatomy, Universität Leipzig, Leipzig, Germany
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Liu S, Yang X, Chen F, Cai ZY. Dysfunction of the neurovascular unit in brain aging. J Biomed Res 2022; 37:153-165. [PMID: 37198158 DOI: 10.7555/jbr.36.20220105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023] Open
Abstract
An emerging concept termed the neurovascular unit (NVU) underlines neurovascular coupling. It has been reported that NVU impairment can result in neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Aging is a complex and irreversible process caused by programmed and damage-related factors. Loss of biological functions and increased susceptibility to additional neurodegenerative diseases are major characteristics of aging. In this review, we describe the basics of the NVU and discuss the effect of aging on NVU basics. Furthermore, we summarize the mechanisms that increase NVU susceptibility to neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Finally, we discuss new treatments for neurodegenerative diseases and methods of maintaining an intact NVU that may delay or diminish aging.
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Affiliation(s)
- Shu Liu
- Chongqing Medical University, Chongqing 400042, China
- Chongqing Institute Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
- Chongqing School, University of Chinese Academy of Sciences, Chongqing 400714, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Xu Yang
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Fei Chen
- Chongqing Medical University, Chongqing 400042, China
- Chongqing Institute Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Zhi-You Cai
- Chongqing Medical University, Chongqing 400042, China
- Chongqing Institute Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
- Chongqing School, University of Chinese Academy of Sciences, Chongqing 400714, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
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Liu S, Gao X, Zhou S. New Target for Prevention and Treatment of Neuroinflammation: Microglia Iron Accumulation and Ferroptosis. ASN Neuro 2022; 14:17590914221133236. [PMID: 36285433 PMCID: PMC9607999 DOI: 10.1177/17590914221133236] [Citation(s) in RCA: 8] [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] [Indexed: 01/24/2023] Open
Abstract
Microglia play an important role in maintaining central nervous system homeostasis and are the major immune cells in the brain. In response to internal or external inflammatory stimuli, microglia are activated and release numerous inflammatory factors, thus leading to neuroinflammation. Inflammation and microglia iron accumulation promote each other and jointly promote the progression of neuroinflammation. Inhibiting microglia iron accumulation prevents neuroinflammation. Ferroptosis is an iron-dependent phospholipid peroxidation-driven type of cell death regulation. Cell iron accumulation causes the peroxidation of cell membrane phospholipids and damages the cell membrane. Ultimately, this process leads to cell ferroptosis. Iron accumulation or phospholipid peroxidation in microglia releases a large number of inflammatory factors. Thus, inhibiting microglia ferroptosis may be a new target for the prevention and treatment of neuroinflammation.
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Affiliation(s)
- Shunfeng Liu
- College of Pharmacy, Guilin Medical College, Guilin, China
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical College, Guilin, China
| | - Xue Gao
- College of Pharmacy, Guilin Medical College, Guilin, China
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical College, Guilin, China
| | - Shouhong Zhou
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical College, Guilin, China
- Basic Medical College, Guilin Medical College, Guilin, China
- Shouhong Zhou, Guilin Medical College, No.1, Zhiyuan Road, Lingui District, Guilin City, Guangxi Province, China.
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Kwon K, Cho H, Lee S, Cho EJ, Yu W, Kok CYL, Je HS, Kim J, Cho HJ, Kwon T. Adaptive cellular response of the substantia nigra dopaminergic neurons upon age-dependent iron accumulation. Aging Cell 2022; 21:e13694. [PMID: 35984750 PMCID: PMC9470899 DOI: 10.1111/acel.13694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 06/20/2022] [Accepted: 07/28/2022] [Indexed: 01/25/2023] Open
Abstract
Progressive iron accumulation in the substantia nigra in the aged human brain is a major risk factor for Parkinson's disease and other neurodegenerative diseases. Heavy metals, such as iron, produce reactive oxygen species and consequently oxidative stress in cells. It is unclear, however, how neurons in the substantia nigra are protected against the age-related, excessive accumulation of iron. In this study, we examined the cellular response of the substantia nigra against age-related iron accumulation in rats of different ages. Magnetic resonance imaging confirmed the presence of iron in 6-month-old rats; in 15-month-old rats, iron accumulation significantly increased, particularly in the midbrain. Transcriptome analysis of the region, in which iron deposition was observed, revealed an increase in stress response genes in older animals. To identify the genes related to the cellular response to iron, independent of neurodevelopment, we exposed the neuroblastoma cell line SH-SY5Y to a similar quantity of iron and then analyzed their transcriptomic responses. Among various stress response pathways altered by iron overloading in the rat brain and SH-SY5Y cells, the genes associated with topologically incorrect protein responses were significantly upregulated. Knockdown of HERPUD1 and CLU in this pathway increased susceptibility to iron-induced cellular stress, thus demonstrating their roles in preventing iron overload-induced toxicity. The current study details the neuronal response to excessive iron accumulation, which is associated with age-related neurodegenerative diseases.
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Affiliation(s)
- Kujin Kwon
- Department of Biomedical Engineering, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea
| | - Hwapyeong Cho
- Department of Biomedical Engineering, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea
| | - Soyeon Lee
- Department of Biological Sciences, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea
| | - Eun Jeong Cho
- Department of Biological Sciences, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea
| | - Weonjin Yu
- Neuroscience and Behavioral Disorders ProgramDuke‐National University of Singapore (NUS) Medical SchoolSingapore CitySingapore
| | - Catherine Yen Li Kok
- Neuroscience and Behavioral Disorders ProgramDuke‐National University of Singapore (NUS) Medical SchoolSingapore CitySingapore
| | - Hyunsoo Shawn Je
- Neuroscience and Behavioral Disorders ProgramDuke‐National University of Singapore (NUS) Medical SchoolSingapore CitySingapore,Advanced Bioimaging Center, AcademiaSingapore CitySingapore
| | - Jae‐Ick Kim
- Department of Biological Sciences, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea
| | - Hyung Joon Cho
- Department of Biomedical Engineering, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea
| | - Taejoon Kwon
- Department of Biomedical Engineering, College of Information and BiotechnologyUlsan National Institute of Science and Technology (UNIST)UlsanKorea,Center for Genome IntegrityInstitute for Basic Science (IBS)UlsanKorea
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11
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Cellular senescence in neuroinflammatory disease: new therapies for old cells? Trends Mol Med 2022; 28:850-863. [DOI: 10.1016/j.molmed.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 07/08/2022] [Accepted: 07/22/2022] [Indexed: 11/23/2022]
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12
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Guan Y, Zhang L, Wang S, Deng Y, Zhou H, Chen D, Zhang L. The role of microglia in Alzheimer's disease and progress of treatment. IBRAIN 2022; 8:37-47. [PMID: 37786418 PMCID: PMC10529349 DOI: 10.1002/ibra.12023] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 01/25/2022] [Indexed: 10/04/2023]
Abstract
Microglia are permanent immune cells of the central nervous system. Microglia play an important role in the pathological process of Alzheimer's disease (AD). They are mainly involved in the uptake and clearance of amyloid-β (Aβ), as well as the formation of neuroinflammation. We found that overactivated microglia increase Aβ and Tau, and Aβ and Tau in turn act as activators of microglia. Additionally, various cytokines and proteins, high cholesterol, and telomere shortening are all associated with microglia activation. More activated microglia induce the release of inflammatory and anti-inflammatory factors to regulate inflammation, while microglia express multiple homologous receptors that bind to neuroimmunomodulators to prevent microglia overactivation. Moreover, aging of the body promotes neuroinflammation by increasing the response to IFN-γ (interferon-γ), and aging of the microglia themselves promotes AD by inducing the accumulation of large amounts of iron and reducing autophagy by regulating protein levels. Cognitive dysfunction occurs when activated microglia induce an increase in beta oligomers, promoting the production of pro-inflammatory factors that alter the shape, composition, and density of synapses. Based on their correlation, microglia-mediated AD therapy as well as the corresponding targets and drugs are discussed. In contrast to similar reviews, this article also summarizes some novel microglia-mediated AD treatment methods over the recent years.
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Affiliation(s)
- Yi‐Huan Guan
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Ling‐Jing Zhang
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Shi‐Ya Wang
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Ya‐Dan Deng
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Hong‐Su Zhou
- Department of AnesthesiaGraduate School of Zunyi Medical UniversityZunyiGuizhouChina
| | - Dong‐Qing Chen
- Department of AnesthesiaGraduate School of Zunyi Medical UniversityZunyiGuizhouChina
| | - Lan‐Chun Zhang
- Department of ZoologyKunming Medical UniversityKunmingChina
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13
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Van Acker ZP, Perdok A, Bretou M, Annaert W. The microglial lysosomal system in Alzheimer's disease: Guardian against proteinopathy. Ageing Res Rev 2021; 71:101444. [PMID: 34391945 DOI: 10.1016/j.arr.2021.101444] [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: 04/26/2021] [Revised: 07/14/2021] [Accepted: 08/08/2021] [Indexed: 12/12/2022]
Abstract
Microglia, the brain-resident immune cells, play an essential role in the upkeep of brain homeostasis. They actively adapt into specific activation states based on cues from the microenvironment. One of these encompasses the activated response microglia (ARMs) phenotype. It arises along a healthy aging process and in a range of neurodegenerative diseases, including Alzheimer's disease (AD). As the phenotype is characterized by an increased lipid metabolism, phagocytosis rate, lysosomal protease content and secretion of neuroprotective agents, it leaves to reason that the phenotype is adapted in an attempt to restore homeostasis. This is important to the conundrum of inflammatory processes. Inflammation per se may not be deleterious; it is only when microglial reactions become chronic or the microglial subtype is made dysfunctional by (multiple) risk proteins with single-nucleotide polymorphisms that microglial involvement becomes deleterious instead of beneficial. Interestingly, the ARMs up- and downregulate many late-onset AD-associated risk factor genes, the products of which are particularly active in the endolysosomal system. Hence, in this review, we focus on how the endolysosomal system is placed at the crossroad of inflammation and microglial capacity to keep pace with degradation.
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14
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Jakaria M, Belaidi AA, Bush AI, Ayton S. Ferroptosis as a mechanism of neurodegeneration in Alzheimer's disease. J Neurochem 2021; 159:804-825. [PMID: 34553778 DOI: 10.1111/jnc.15519] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 09/07/2021] [Accepted: 09/14/2021] [Indexed: 01/19/2023]
Abstract
Alzheimer's disease (AD) is the most prevalent form of dementia, with complex pathophysiology that is not fully understood. While β-amyloid plaque and neurofibrillary tangles define the pathology of the disease, the mechanism of neurodegeneration is uncertain. Ferroptosis is an iron-mediated programmed cell death mechanism characterised by phospholipid peroxidation that has been observed in clinical AD samples. This review will outline the growing molecular and clinical evidence implicating ferroptosis in the pathogenesis of AD, with implications for disease-modifying therapies.
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Affiliation(s)
- Md Jakaria
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Abdel Ali Belaidi
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Ashley I Bush
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Scott Ayton
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
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15
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Uddin MS, Yu WS, Lim LW. Exploring ER stress response in cellular aging and neuroinflammation in Alzheimer's disease. Ageing Res Rev 2021; 70:101417. [PMID: 34339860 DOI: 10.1016/j.arr.2021.101417] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 02/06/2023]
Abstract
One evident hallmark of Alzheimer's disease (AD) is the irregular accumulation of proteins due to changes in proteostasis involving endoplasmic reticulum (ER) stress. To alleviate ER stress and reinstate proteostasis, cells undergo an integrated signaling cascade called the unfolded protein response (UPR) that reduces the number of misfolded proteins and inhibits abnormal protein accumulation. Aging is associated with changes in the expression of ER chaperones and folding enzymes, leading to the impairment of proteostasis, and accumulation of misfolded proteins. The disrupted initiation of UPR prevents the elimination of unfolded proteins, leading to ER stress. In AD, the accumulation of misfolded proteins caused by sustained cellular stress leads to neurodegeneration and neuronal death. Current research has revealed that ER stress can trigger an inflammatory response through diverse transducers of UPR. Although the involvement of a neuroinflammatory component in AD has been documented for decades, whether it is a contributing factor or part of the neurodegenerative events is so far unknown. Besides, a feedback loop occurs between neuroinflammation and ER stress, which is strongly associated with neurodegenerative processes in AD. In this review, we focus on the current research on ER stress and UPR in cellular aging and neuroinflammatory processes, leading to memory impairment and synapse dysfunction in AD.
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16
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Xu L, Wang Y, Wang J, Zhai J, Ren L, Zhu G. Radiation-Induced Osteocyte Senescence Alters Bone Marrow Mesenchymal Stem Cell Differentiation Potential via Paracrine Signaling. Int J Mol Sci 2021; 22:ijms22179323. [PMID: 34502232 PMCID: PMC8430495 DOI: 10.3390/ijms22179323] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 08/24/2021] [Accepted: 08/26/2021] [Indexed: 02/07/2023] Open
Abstract
Cellular senescence and its senescence-associated secretory phenotype (SASP) are widely regarded as promising therapeutic targets for aging-related diseases, such as osteoporosis. However, the expression pattern of cellular senescence and multiple SASP secretion remains unclear, thus leaving a large gap in the knowledge for a desirable intervention targeting cellular senescence. Therefore, there is a critical need to understand the molecular mechanism of SASP secretion in the bone microenvironment that can ameliorate aging-related degenerative pathologies including osteoporosis. In this study, osteocyte-like cells (MLO-Y4) were induced to cellular senescence by 2 Gy γ-rays; then, senescence phenotype changes and adverse effects of SASP on bone marrow mesenchymal stem cell (BMSC) differentiation potential were investigated. The results revealed that 2 Gy irradiation could hinder cell viability, shorten cell dendrites, and induce cellular senescence, as evidenced by the higher expression of senescence markers p16 and p21 and the elevated formation of senescence-associated heterochromatin foci (SAHF), which was accompanied by the enhanced secretion of SASP markers such as IL-1α, IL-6, MMP-3, IGFBP-6, resistin, and adiponectin. When 0.8 μM JAK1 inhibitors were added to block SASP secretion, the higher expression of SASP was blunted, but the inhibition in osteogenic and adipogenic differentiation potential of BMSCs co-cultured with irradiated MLO-Y4 cell conditioned medium (CM- 2 Gy) was alleviated. These results suggest that senescent osteocytes can perturb BMSCs’ differential potential via the paracrine signaling of SASP, which was also demonstrated by in vivo experiments. In conclusion, we identified the SASP factor partially responsible for the degenerative differentiation of BMSCs, which allowed us to hypothesize that senescent osteocytes and their SASPs may contribute to radiation-induced bone loss.
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17
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Guerrero A, De Strooper B, Arancibia-Cárcamo IL. Cellular senescence at the crossroads of inflammation and Alzheimer's disease. Trends Neurosci 2021; 44:714-727. [PMID: 34366147 DOI: 10.1016/j.tins.2021.06.007] [Citation(s) in RCA: 108] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/14/2022]
Abstract
Aging is a key risk factor for Alzheimer's disease (AD), but the reasons for this association are not well understood. Senescent cells accumulate in aged tissues and have been shown to play causal roles in age-related pathologies through their proinflammatory secretome. The question arises whether senescence-induced inflammation might contribute to AD and bridge the gap between aging and AD. Here, we highlight the role of cellular senescence as a driver of the aging phenotype, and discuss the current evidence that connects senescence with AD and neurodegeneration.
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Affiliation(s)
- Ana Guerrero
- UK Dementia Research Institute, Institute of Neurology, University College London, London WC1E 6BT, UK; The Francis Crick Institute, London NW1 1AT, UK
| | - Bart De Strooper
- UK Dementia Research Institute, Institute of Neurology, University College London, London WC1E 6BT, UK; The Francis Crick Institute, London NW1 1AT, UK; Department of Neurosciences, Leuven Brain Institute, Katholieke Universiteit (KU) Leuven, Leuven, Belgium; Vlaams Instituut voor Biotechnologie (VIB) Centre for Brain and Disease Research, Leuven, Belgium
| | - I Lorena Arancibia-Cárcamo
- UK Dementia Research Institute, Institute of Neurology, University College London, London WC1E 6BT, UK; The Francis Crick Institute, London NW1 1AT, UK.
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18
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Zhang PF, Hu H, Tan L, Yu JT. Microglia Biomarkers in Alzheimer's Disease. Mol Neurobiol 2021; 58:3388-3404. [PMID: 33713018 DOI: 10.1007/s12035-021-02348-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 03/03/2021] [Indexed: 12/13/2022]
Abstract
Early detection and clinical diagnosis of Alzheimer's disease (AD) have become an extremely important link in the prevention and treatment of AD. Because of the occult onset, the diagnosis and treatment of AD based on clinical symptoms are increasingly challenged by current severe situations. Therefore, molecular diagnosis models based on early AD pathological markers have received more attention. Among the possible pathological mechanisms, microglia which are necessary for normal brain function are highly expected and have been continuously studied in various models. Several AD biomarkers already exist, but currently there is a paucity of specific and sensitive microglia biomarkers which can accurately measure preclinical AD. Bringing microglia biomarkers into the molecular diagnostic system which is based on fluid and neuroimaging will play an important role in future scientific research and clinical practice. Furthermore, developing novel, more specific, and sensitive microglia biomarkers will make it possible to pharmaceutically target chemical pathways that preserve beneficial microglial functions in response to AD pathology. This review discusses microglia biomarkers in the context of AD.
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Affiliation(s)
- Peng-Fei Zhang
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, No.5 Donghai Middle Road, Qingdao, China
| | - Hao Hu
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, No.5 Donghai Middle Road, Qingdao, China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, No.5 Donghai Middle Road, Qingdao, China.
| | - Jin-Tai Yu
- Department of Neurology and Institute of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, China.
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Senescent Microglia: The Key to the Ageing Brain? Int J Mol Sci 2021; 22:ijms22094402. [PMID: 33922383 PMCID: PMC8122783 DOI: 10.3390/ijms22094402] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 12/13/2022] Open
Abstract
Ageing represents the single biggest risk factor for development of neurodegenerative disease. Despite being such long-lived cells, microglia have been relatively understudied for their role in the ageing process. Reliably identifying aged microglia has proven challenging, not least due to the diversity of cell populations, and the limitations of available models, further complicated by differences between human and rodent cells. Consequently, the literature contains multiple descriptions and categorisations of microglia with neurotoxic phenotypes, including senescence, without any unifying markers. The role of microglia in brain homeostasis, particularly iron storage and metabolism, may provide a key to reliable identification.
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20
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Kuang H, Tan C, Tian H, Liu L, Yang M, Hong F, Yang S. Exploring the bi-directional relationship between autophagy and Alzheimer's disease. CNS Neurosci Ther 2020; 26:155-166. [PMID: 31503421 PMCID: PMC6978262 DOI: 10.1111/cns.13216] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/11/2019] [Accepted: 08/15/2019] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by β-amyloid (Aβ) deposition and Tau phosphorylation, in which its pathogenesis has not been cleared so far. The metabolism of Aβ and Tau is critically affected by the autophagy. Abnormal autophagy is thought to be involved in the pathogenesis of AD, regulating autophagy may become a new strategy for AD treatment. In the early stage of AD, the presence of Aβ and Tau can induce autophagy to promote their clearance by means of mTOR-dependent and independent manners. As AD progress, the autophagy goes aberrant. As a result, Aβ and Tau generate continually, which aggravates both autophagy dysfunction and AD. Besides, several related genes and proteins of AD can also adapt autophagy to make an effect on the AD development. There seems to be a bi-directional relationship between AD pathology and autophagy. At present, this article reviews this relationship from these aspects: (a) the signaling pathways of regulating autophagy; (b) the relationships between the autophagy and the processing of Aβ; (c) Aβ and Tau cause autophagy dysfunction; (d) normal autophagy promotes the clearance of Aβ and Tau; (e) the relationships between the autophagy and both genes and proteins related to AD: TFEB, miRNAs, Beclin-1, Presenilin, and Nrf2; and (f) the small molecules regulating autophagy on AD therapy. All of the above may help to further elucidate the pathogenesis of AD and provide a theoretical basis for clinical treatment of AD.
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Affiliation(s)
- Huang Kuang
- Department of Physiology, College of MedicineNanchang UniversityNanchangChina
| | - Cheng‐Yong Tan
- Department of Physiology, College of MedicineNanchang UniversityNanchangChina
| | - Hui‐Zhen Tian
- Department of Physiology, College of MedicineNanchang UniversityNanchangChina
| | - Li‐Hua Liu
- Department of Physiology, College of MedicineNanchang UniversityNanchangChina
| | - Mei‐Wen Yang
- Department of NurseNanchang University HospitalNanchangChina
| | - Fen‐Fang Hong
- Department of Experimental Teaching CenterNanchang UniversityNanchangChina
| | - Shu‐Long Yang
- Department of Physiology, College of MedicineNanchang UniversityNanchangChina
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21
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Angelova DM, Brown DR. Microglia and the aging brain: are senescent microglia the key to neurodegeneration? J Neurochem 2019; 151:676-688. [PMID: 31478208 DOI: 10.1111/jnc.14860] [Citation(s) in RCA: 139] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/21/2019] [Accepted: 08/23/2019] [Indexed: 12/15/2022]
Abstract
The single largest risk factor for etiology of neurodegenerative diseases like Alzheimer's disease is increased age. Therefore, understanding the changes that occur as a result of aging is central to any possible prevention or cure for such conditions. Microglia, the resident brain glial population most associated with both protection of neurons in health and their destruction is disease, could be a significant player in age related changes. Microglia can adopt an aberrant phenotype sometimes referred to either as dystrophic or senescent. While aged microglia have been frequently identified in neurodegenerative diseases such as Alzheimer's disease, there is no conclusive evidence that proves a causal role. This has been hampered by a lack of models of aged microglia. We have recently generated a model of senescent microglia based on the observation that all dystrophic microglia show iron overload. Iron-overloading cultured microglia causes them to take on a senescent phenotype and can cause changes in models of neurodegeneration similar to those observed in patients. This review considers how this model could be used to determine the role of senescent microglia in neurodegenerative diseases.
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Affiliation(s)
- Dafina M Angelova
- Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - David R Brown
- Department of Biology and Biochemistry, University of Bath, Bath, UK
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22
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Masaldan S, Belaidi AA, Ayton S, Bush AI. Cellular Senescence and Iron Dyshomeostasis in Alzheimer's Disease. Pharmaceuticals (Basel) 2019; 12:E93. [PMID: 31248150 PMCID: PMC6630536 DOI: 10.3390/ph12020093] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 02/07/2023] Open
Abstract
Iron dyshomeostasis is a feature of Alzheimer's disease (AD). The impact of iron on AD is attributed to its interactions with the central proteins of AD pathology (amyloid precursor protein and tau) and/or through the iron-mediated generation of prooxidant molecules (e.g., hydroxyl radicals). However, the source of iron accumulation in pathologically relevant regions of the brain and its contribution to AD remains unclear. One likely contributor to iron accumulation is the age-associated increase in tissue-resident senescent cells that drive inflammation and contribute to various pathologies associated with advanced age. Iron accumulation predisposes ageing tissue to oxidative stress that can lead to cellular dysfunction and to iron-dependent cell death modalities (e.g., ferroptosis). Further, elevated brain iron is associated with the progression of AD and cognitive decline. Elevated brain iron presents a feature of AD that may be modified pharmacologically to mitigate the effects of age/senescence-associated iron dyshomeostasis and improve disease outcome.
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Affiliation(s)
- Shashank Masaldan
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
| | - Abdel Ali Belaidi
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
| | - Scott Ayton
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
| | - Ashley I Bush
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
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Delikkaya B, Moriel N, Tong M, Gallucci G, de la Monte SM. Altered expression of insulin-degrading enzyme and regulator of calcineurin in the rat intracerebral streptozotocin model and human apolipoprotein E-ε4-associated Alzheimer's disease. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2019; 11:392-404. [PMID: 31193223 PMCID: PMC6522644 DOI: 10.1016/j.dadm.2019.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION This study assesses insulin-degrading enzyme (IDE) and regulator of calcineurin 1 (RCAN1) as potential mediators of brain insulin deficiency and neurodegeneration in experimental and human Alzheimer's disease (AD). METHODS Temporal lobes from Long Evans rats treated with intracerebral streptozotocin or vehicle and postmortem frontal lobes from humans with normal aging AD (Braak 0-2), moderate (Braak 3-4) AD, or advanced (Braak 5-6) AD were used to measure IDE and RCAN mRNA and protein. RESULTS Intracerebral streptozotocin significantly increased IDE and RCAN mRNA and protein. In humans with apolipoprotein E (ApoE) ε3/ε4 or ε4/ε4 and AD, IDE was elevated at Braak 3-4, but at Braak 5-6, IDE expression was significantly reduced. RCAN1 mRNA was similarly reduced in ApoE ε4+ patients with moderate or severe AD, whereas RCAN1 protein declined with the severity of AD and ApoE ε4 dose. DISCUSSION The findings suggest that IDE and RCAN1 differentially modulate brain insulin signaling in relation to AD severity and ApoE genotype.
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Affiliation(s)
- Büşra Delikkaya
- Istanbul University-Cerrahpasa Cerrahpasa Medical Faculty, Istanbul, Turkey
| | - Natalia Moriel
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA
| | - Ming Tong
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA,Alpert Medical School of Brown University, Providence, RI, USA
| | - Gina Gallucci
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA
| | - Suzanne M. de la Monte
- Department of Medicine, Rhode Island Hospital, Providence, RI, USA,Alpert Medical School of Brown University, Providence, RI, USA,Departments of Neurology and Neurosurgery, Rhode Island Hospital, Providence, RI, USA,Department of Pathology and Laboratory Medicine, Providence VA Medical Center, Providence, RI, USA,Corresponding author. Tel.: +401-444-7364; Fax: +401-444-2939.
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