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Volloch V, Rits-Volloch S. Quintessential Synergy: Concurrent Transient Administration of Integrated Stress Response Inhibitors and BACE1 and/or BACE2 Activators as the Optimal Therapeutic Strategy for Alzheimer's Disease. Int J Mol Sci 2024; 25:9913. [PMID: 39337400 PMCID: PMC11432332 DOI: 10.3390/ijms25189913] [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: 08/14/2024] [Revised: 09/01/2024] [Accepted: 09/03/2024] [Indexed: 09/30/2024] Open
Abstract
The present study analyzes two potential therapeutic approaches for Alzheimer's disease (AD). One is the suppression of the neuronal integrated stress response (ISR). Another is the targeted degradation of intraneuronal amyloid-beta (iAβ) via the activation of BACE1 (Beta-site Aβ-protein-precursor Cleaving Enzyme) and/or BACE2. Both approaches are rational. Both are promising. Both have substantial intrinsic limitations. However, when combined in a carefully orchestrated manner into a composite therapy they display a prototypical synergy and constitute the apparently optimal, potentially most effective therapeutic strategy for AD.
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Affiliation(s)
- Vladimir Volloch
- Department of Developmental Biology, Harvard School of Dental Medicine, Boston, MA 02115, USA
| | - Sophia Rits-Volloch
- Division of Molecular Medicine, Children’s Hospital, Boston, MA 02115, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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2
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Liu E, Zhang Y, Wang JZ. Updates in Alzheimer's disease: from basic research to diagnosis and therapies. Transl Neurodegener 2024; 13:45. [PMID: 39232848 PMCID: PMC11373277 DOI: 10.1186/s40035-024-00432-x] [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: 03/12/2024] [Accepted: 07/11/2024] [Indexed: 09/06/2024] Open
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder, characterized pathologically by extracellular deposition of β-amyloid (Aβ) into senile plaques and intracellular accumulation of hyperphosphorylated tau (pTau) as neurofibrillary tangles. Clinically, AD patients show memory deterioration with varying cognitive dysfunctions. The exact molecular mechanisms underlying AD are still not fully understood, and there are no efficient drugs to stop or reverse the disease progression. In this review, we first provide an update on how the risk factors, including APOE variants, infections and inflammation, contribute to AD; how Aβ and tau become abnormally accumulated and how this accumulation plays a role in AD neurodegeneration. Then we summarize the commonly used experimental models, diagnostic and prediction strategies, and advances in periphery biomarkers from high-risk populations for AD. Finally, we introduce current status of development of disease-modifying drugs, including the newly officially approved Aβ vaccines, as well as novel and promising strategies to target the abnormal pTau. Together, this paper was aimed to update AD research progress from fundamental mechanisms to the clinical diagnosis and therapies.
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Affiliation(s)
- Enjie Liu
- Department of Pathology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Yao Zhang
- Department of Endocrine, Liyuan Hospital, Key Laboratory of Ministry of Education for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430077, China
| | - Jian-Zhi Wang
- Department of Pathology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
- Department of Pathophysiology, Key Laboratory of Ministry of Education for Neurological Disorders, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, 226000, China.
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Zhao M, Wang Y, Shen Y, Wei C, Zhang G, Sun L. A review of the roles of pathogens in Alzheimer's disease. Front Neurosci 2024; 18:1439055. [PMID: 39224577 PMCID: PMC11366636 DOI: 10.3389/fnins.2024.1439055] [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: 05/27/2024] [Accepted: 08/01/2024] [Indexed: 09/04/2024] Open
Abstract
Alzheimer's disease (AD) is one of the leading causes of dementia and is characterized by memory loss, mental and behavioral abnormalities, and impaired ability to perform daily activities. Even as a global disease that threatens human health, effective treatments to slow the progression of AD have not been found, despite intensive research and significant investment. In recent years, the role of infections in the etiology of AD has sparked intense debate. Pathogens invade the central nervous system through a damaged blood-brain barrier or nerve trunk and disrupt the neuronal structure and function as well as homeostasis of the brain microenvironment through a series of molecular biological events. In this review, we summarize the various pathogens involved in AD pathology, discuss potential interactions between pathogens and AD, and provide an overview of the promising future of anti-pathogenic therapies for AD.
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Affiliation(s)
| | | | | | | | | | - Li Sun
- Department of Neurology, Neuroscience Center, The First Hospital of Jilin University, Jilin University, Changchun, China
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Teng S, Han C, Zhou J, He Z, Qian W. m 5C RNA methylation: a potential mechanism for infectious Alzheimer's disease. Front Cell Dev Biol 2024; 12:1440143. [PMID: 39175875 PMCID: PMC11338875 DOI: 10.3389/fcell.2024.1440143] [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: 05/30/2024] [Accepted: 07/30/2024] [Indexed: 08/24/2024] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder caused by a variety of factors, including age, genetic susceptibility, cardiovascular disease, traumatic brain injury, and environmental factors. The pathogenesis of AD is largely associated with the overproduction and accumulation of amyloid-β peptides and the hyperphosphorylation of tau protein in the brain. Recent studies have identified the presence of diverse pathogens, including viruses, bacteria, and parasites, in the tissues of AD patients, underscoring the critical role of central nervous system infections in inducing pathological changes associated with AD. Nevertheless, it remains unestablished about the specific mechanism by which infections lead to the occurrence of AD. As an important post-transcriptional RNA modification, RNA 5-methylcytosine (m5C) methylation regulates a wide range of biological processes, including RNA splicing, nuclear export, stability, and translation, therefore affecting cellular function. Moreover, it has been recently demonstrated that multiple pathogenic microbial infections are associated with the m5C methylation of the host. However, the role of m5C methylation in infectious AD is still uncertain. Therefore, this review discusses the mechanisms of pathogen-induced AD and summarizes research on the molecular mechanisms of m5C methylation in infectious AD, thereby providing new insight into exploring the mechanism underlying infectious AD.
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Affiliation(s)
- Sisi Teng
- Department of Neurology, Shangjinnanfu Hospital, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Cunqiao Han
- Department of Emergency, Shangjinnanfu Hospital, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jian Zhou
- Department of Immunology, International Cancer Center, Shenzhen University Health Science Center, Shenzhen, Guangdong, China
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen, Guangdong, China
| | - Zhenyan He
- Department of Neurosurgery, The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China
| | - Weiwei Qian
- Department of Emergency, Shangjinnanfu Hospital, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Emergency Medicine, Laboratory of Emergency Medicine, West China Hospital, and Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
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Sait AM, Day PJR. Interconnections between the Gut Microbiome and Alzheimer's Disease: Mechanisms and Therapeutic Potential. Int J Mol Sci 2024; 25:8619. [PMID: 39201303 PMCID: PMC11354889 DOI: 10.3390/ijms25168619] [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: 06/18/2024] [Revised: 07/23/2024] [Accepted: 08/06/2024] [Indexed: 09/02/2024] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease that is known to accumulate amyloid-β (Aβ) and tau protein. Clinical studies have not identified pathogenesis mechanisms or produced an effective cure for AD. The Aβ monoclonal antibody lecanemab reduces Aβ plaque formation for the treatment of AD, but more studies are required to increase the effectiveness of drugs to reduce cognitive decline. The lack of AD therapy targets and evidence of an association with an acute neuroinflammatory response caused by several bacteria and viruses in some individuals has led to the establishment of the infection hypothesis during the last 10 years. How pathogens cross the blood-brain barrier is highly topical and is seen to be pivotal in proving the hypothesis. This review summarizes the possible role of the gut microbiome in the pathogenesis of AD and feasible therapeutic approaches and current research limitations.
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Affiliation(s)
- Ahmad M. Sait
- Medical Laboratory Science, Faculty of Applied Medical Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Regenerative Medicine Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Philip J. R. Day
- Division of Evolution and Genomic Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PL, UK
- Department of Medicine, University of Cape Town, Cape Town 7925, South Africa
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Rajendrakumar AL, Arbeev KG, Bagley O, Yashin AI, Ukraintseva S. The association between rs6859 in NECTIN2 gene and Alzheimer's disease is partly mediated by pTau. Front Aging Neurosci 2024; 16:1388363. [PMID: 39165837 PMCID: PMC11334082 DOI: 10.3389/fnagi.2024.1388363] [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: 02/19/2024] [Accepted: 07/18/2024] [Indexed: 08/22/2024] Open
Abstract
Introduction Emerging evidence suggests a connection between vulnerability to infections and Alzheimer's disease (AD). The nectin cell adhesion molecule 2 (NECTIN2) gene coding for a membrane component of adherens junctions is involved in response to infections, and its single nucleotide polymorphism (SNP) rs6859 was significantly associated with AD risk in several human cohorts. It is unclear, however, how exactly rs6859 influences the development of AD pathology. The aggregation of hyperphosphorylated tau protein (pTau) is a key pathological feature of neurodegeneration in AD, which may be induced by infections, among other factors, and potentially influenced by genes involved in both AD and vulnerability to infections, such as NECTIN2. Materials and methods We conducted a causal mediation analysis (CMA) on a sample of 708 participants in the Alzheimer's disease Neuroimaging Initiative (ADNI). The relationship between rs6859 and Alzheimer's disease (AD), with AD (yes/no) as the outcome and pTau-181 levels in the cerebrospinal fluid (CSF) acting as a mediator in this association, was assessed. Adjusted estimates from the probit and linear regression models were used in the CMA model, where an additive model considered an increase in dosage of the rs6859 A allele (AD risk factor). Results The increase in dose of allele A of the SNP rs6859 resulted in about 0.144 increase per standard deviation (SD) of pTau-181 (95% CI: 0.041, 0.248, p < 0.01). When included together in the probit model, the change in A allele dose and each standard deviation change in pTau-181 predicted 6.84% and 9.79% higher probabilities for AD, respectively. In the CMA, the proportion of the average mediated effect was 17.05% and was higher for the risk allele homozygotes (AA), at 19.40% (95% CI: 6.20%, 43.00%, p < 0.01). The sensitivity analysis confirmed the evidence of a robust mediation effect. Conclusion This study reported a new potential causal relationship between pTau-181 and AD. We found that the association between rs6859 in the NECTIN2 gene and AD is partly mediated by pTau-181 levels in CSF. The rest of this association may be mediated by other factors. Our finding sheds light on the complex interplay between genetic susceptibility, protein aggregation, and neurodegeneration in AD. Further research, using other biomarkers, is needed to uncover the remaining mechanisms of the association between the NECTIN2 gene and AD.
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Affiliation(s)
| | | | | | | | - Svetlana Ukraintseva
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, United States
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Rajendrakumar AL, Arbeev KG, Bagley O, Yashin AI, Ukraintseva S. The association between rs6859 in NECTIN2 gene and Alzheimer's disease is partly mediated by pTau. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.06.21.24309310. [PMID: 38947013 PMCID: PMC11213054 DOI: 10.1101/2024.06.21.24309310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Introduction Emerging evidence suggests a connection between vulnerability to infections and Alzheimer's disease (AD). The nectin cell adhesion molecule 2 (NECTIN2) gene coding for a membrane component of adherens junctions is involved in response to infection, and its single nucleotide polymorphism (SNP) rs6859 was significantly associated with AD risk in several human cohorts. It is unclear, however, how exactly rs6859 influences the development of AD pathology. The aggregation of hyperphosphorylated tau protein (pTau) is a key pathological feature of neurodegeneration in AD, which may be induced by infections, among other factors, and potentially influenced by genes involved in both AD and vulnerability to infections, such as NECTIN2. Materials and methods We conducted a causal mediation analysis (CMA) on a sample of 708 participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI). The relationship between rs6859 and Alzheimer's disease (AD), with AD (yes/no) as the outcome and pTau-181 levels in the cerebrospinal fluid (CSF) acting as a mediator in this association, was assessed. Adjusted estimates from the probit and linear regression models were used in the CMA model, where an additive model considered an increase in dosage of the rs6859 A allele (AD risk factor). Results The increase in dose of allele A of the SNP rs6859 resulted in about 0.144 increase per standard deviation (SD) of pTau-181 (95% CI: 0.041, 0.248, p<0.01). When included together in the probit model, the change in A allele dose and each standard deviation change in pTau-181 predicted 6.84% and 9.79% higher probabilities for AD, respectively. In the CMA, the proportion of the average mediated effect was 17.05% and was higher for the risk allele homozygotes (AA), at 19.40% (95% CI: 6.20%, 43.00%, p<0.01). The sensitivity analysis confirmed the evidence of a robust mediation effect. Conclusion This study reported a new causal relationship between pTau-181 and AD. We found that the association between rs6859 in the NECTIN2 gene and AD is partly mediated by pTau-181 levels in CSF. The rest of this association may be mediated by other factors. Further research, using other biomarkers, is needed to uncover the remaining mechanisms of the association between the NECTIN2 gene and AD.
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Affiliation(s)
| | - Konstantin G. Arbeev
- Biodemography of Aging Research Unit, Duke University, Social Science Research Institute, Durham, NC, USA
| | - Olivia Bagley
- Biodemography of Aging Research Unit, Duke University, Social Science Research Institute, Durham, NC, USA
| | - Anatoliy I. Yashin
- Biodemography of Aging Research Unit, Duke University, Social Science Research Institute, Durham, NC, USA
| | - Svetlana Ukraintseva
- Biodemography of Aging Research Unit, Duke University, Social Science Research Institute, Durham, NC, USA
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8
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Diez I, Ortiz-Terán L, Ng TSC, Albers MW, Marshall G, Orwig W, Kim CM, Bueichekú E, Montal V, Olofsson J, Vannini P, El Fahkri G, Sperling R, Johnson K, Jacobs HIL, Sepulcre J. Tau propagation in the brain olfactory circuits is associated with smell perception changes in aging. Nat Commun 2024; 15:4809. [PMID: 38844444 PMCID: PMC11156945 DOI: 10.1038/s41467-024-48462-3] [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: 10/07/2022] [Accepted: 04/30/2024] [Indexed: 06/09/2024] Open
Abstract
The direct access of olfactory afferents to memory-related cortical systems has inspired theories about the role of the olfactory pathways in the development of cortical neurodegeneration in Alzheimer's disease (AD). In this study, we used baseline olfactory identification measures with longitudinal flortaucipir and PiB PET, diffusion MRI of 89 cognitively normal older adults (73.82 ± 8.44 years; 56% females), and a transcriptomic data atlas to investigate the spatiotemporal spreading and genetic vulnerabilities of AD-related pathology aggregates in the olfactory system. We find that odor identification deficits are predominantly associated with tau accumulation in key areas of the olfactory pathway, with a particularly strong predictive power for longitudinal tau progression. We observe that tau spreads from the medial temporal lobe structures toward the olfactory system, not the reverse. Moreover, we observed a genetic background of odor perception-related genes that might confer vulnerability to tau accumulation along the olfactory system.
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Affiliation(s)
- Ibai Diez
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Laura Ortiz-Terán
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- UMASS Memorial Medical Center, UMASS Chan Medical School, Worcester, MA, USA
| | - Thomas S C Ng
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Mark W Albers
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Gad Marshall
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - William Orwig
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Harvard University, Department of Psychology, Cambridge, MA, USA
| | - Chan-Mi Kim
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Elisenda Bueichekú
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Victor Montal
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Barcelona Supercomputing Center, Barcelona, Spain
| | - Jonas Olofsson
- Stockholm University, Department of Psychology, Stockholm, Sweden
| | - Patrizia Vannini
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Georges El Fahkri
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Reisa Sperling
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Keith Johnson
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Heidi I L Jacobs
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jorge Sepulcre
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.
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Volloch V, Rits-Volloch S. ACH2.0/E, the Consolidated Theory of Conventional and Unconventional Alzheimer's Disease: Origins, Progression, and Therapeutic Strategies. Int J Mol Sci 2024; 25:6036. [PMID: 38892224 PMCID: PMC11172602 DOI: 10.3390/ijms25116036] [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: 04/16/2024] [Revised: 05/19/2024] [Accepted: 05/21/2024] [Indexed: 06/21/2024] Open
Abstract
The centrality of amyloid-beta (Aβ) is an indisputable tenet of Alzheimer's disease (AD). It was initially indicated by the detection (1991) of a mutation within Aβ protein precursor (AβPP) segregating with the disease, which served as a basis for the long-standing Amyloid Cascade Hypothesis (ACH) theory of AD. In the intervening three decades, this notion was affirmed and substantiated by the discovery of numerous AD-causing and AD-protective mutations with all, without an exception, affecting the structure, production, and intraneuronal degradation of Aβ. The ACH postulated that the disease is caused and driven by extracellular Aβ. When it became clear that this is not the case, and the ACH was largely discredited, a new theory of AD, dubbed ACH2.0 to re-emphasize the centrality of Aβ, was formulated. In the ACH2.0, AD is caused by physiologically accumulated intraneuronal Aβ (iAβ) derived from AβPP. Upon reaching the critical threshold, it triggers activation of the autonomous AβPP-independent iAβ generation pathway; its output is retained intraneuronally and drives the AD pathology. The bridge between iAβ derived from AβPP and that generated independently of AβPP is the neuronal integrated stress response (ISR) elicited by the former. The ISR severely suppresses cellular protein synthesis; concurrently, it activates the production of a small subset of proteins, which apparently includes components necessary for operation of the AβPP-independent iAβ generation pathway that are absent under regular circumstances. The above sequence of events defines "conventional" AD, which is both caused and driven by differentially derived iAβ. Since the ISR can be elicited by a multitude of stressors, the logic of the ACH2.0 mandates that another class of AD, referred to as "unconventional", has to occur. Unconventional AD is defined as a disease where a stressor distinct from AβPP-derived iAβ elicits the neuronal ISR. Thus, the essence of both, conventional and unconventional, forms of AD is one and the same, namely autonomous, self-sustainable, AβPP-independent production of iAβ. What distinguishes them is the manner of activation of this pathway, i.e., the mode of causation of the disease. In unconventional AD, processes occurring at locations as distant from and seemingly as unrelated to the brain as, say, the knee can potentially trigger the disease. The present study asserts that these processes include traumatic brain injury (TBI), chronic traumatic encephalopathy, viral and bacterial infections, and a wide array of inflammatory conditions. It considers the pathways which are common to all these occurrences and culminate in the elicitation of the neuronal ISR, analyzes the dynamics of conventional versus unconventional AD, shows how the former can morph into the latter, explains how a single TBI can hasten the occurrence of AD and why it takes multiple TBIs to trigger the disease, and proposes the appropriate therapeutic strategies. It posits that yet another class of unconventional AD may occur where the autonomous AβPP-independent iAβ production pathway is initiated by an ISR-unrelated activator, and consolidates the above notions in a theory of AD, designated ACH2.0/E (for expanded ACH2.0), which incorporates the ACH2.0 as its special case and retains the centrality of iAβ produced independently of AβPP as the driving agent of the disease.
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Affiliation(s)
- Vladimir Volloch
- Department of Developmental Biology, Harvard School of Dental Medicine, Boston, MA 02115, USA
| | - Sophia Rits-Volloch
- Division of Molecular Medicine, Children’s Hospital, Boston, MA 02115, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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Wongchitrat P, Chanmee T, Govitrapong P. Molecular Mechanisms Associated with Neurodegeneration of Neurotropic Viral Infection. Mol Neurobiol 2024; 61:2881-2903. [PMID: 37946006 PMCID: PMC11043213 DOI: 10.1007/s12035-023-03761-6] [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: 08/25/2022] [Accepted: 10/31/2023] [Indexed: 11/12/2023]
Abstract
Viral infections of the central nervous system (CNS) cause variable outcomes from acute to severe neurological sequelae with increased morbidity and mortality. Viral neuroinvasion directly or indirectly induces encephalitis via dysregulation of the immune response and contributes to the alteration of neuronal function and the degeneration of neuronal cells. This review provides an overview of the cellular and molecular mechanisms of virus-induced neurodegeneration. Neurotropic viral infections influence many aspects of neuronal dysfunction, including promoting chronic inflammation, inducing cellular oxidative stress, impairing mitophagy, encountering mitochondrial dynamics, enhancing metabolic rewiring, altering neurotransmitter systems, and inducing misfolded and aggregated pathological proteins associated with neurodegenerative diseases. These pathogenetic mechanisms create a multidimensional injury of the brain that leads to specific neuronal and brain dysfunction. The understanding of the molecular mechanisms underlying the neurophathogenesis associated with neurodegeneration of viral infection may emphasize the strategies for prevention, protection, and treatment of virus infection of the CNS.
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Affiliation(s)
- Prapimpun Wongchitrat
- Center for Research Innovation and Biomedical Informatics, Faculty of Medical Technology, Mahidol University, 999 Phutthamonthon 4 Road, Salaya, Phutthamonthon, Nakhon Pathom, 73170, Thailand.
| | - Theerawut Chanmee
- Department of Clinical Chemistry, Faculty of Medical Technology, Mahidol University, Salaya, Nakhon Pathom, Thailand
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11
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Sanami S, Shamsabadi S, Dayhimi A, Pirhayati M, Ahmad S, Pirhayati A, Ajami M, Hemati S, Shirvani M, Alagha A, Abbarin D, Alizadeh A, Pazoki-Toroudi H. Association between cytomegalovirus infection and neurological disorders: A systematic review. Rev Med Virol 2024; 34:e2532. [PMID: 38549138 DOI: 10.1002/rmv.2532] [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: 01/30/2024] [Revised: 03/11/2024] [Accepted: 03/14/2024] [Indexed: 04/02/2024]
Abstract
Cytomegalovirus (CMV) belongs to the Herpesviridae family and is also known as human herpesvirus type 5. It is a common virus that usually doesn't cause any symptoms in healthy individuals. However, once infected, the virus remains in the host's body for life and can reactivate when the host's immune system weakens. This virus has been linked to several neurological disorders, including Alzheimer's disease, Parkinson's disease, Autism spectrum disorder, Huntington's disease (HD), ataxia, Bell's palsy (BP), and brain tumours, which can cause a wide range of symptoms and challenges for those affected. CMV may influence inflammation, contribute to brain tissue damage, and elevate the risk of moderate-to-severe dementia. Multiple studies suggest a potential association between CMV and ataxia in various conditions, including Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, acute cerebellitis, etc. On the other hand, the evidence regarding CMV involvement in BP is conflicting, and also early indications of a link between CMV and HD were challenged by subsequent research disproving CMV's presence. This systematic review aims to comprehensively investigate any link between the pathogenesis of CMV and its potential role in neurological disorders and follows the preferred reporting items for systematic review and meta-analysis checklist. Despite significant research into the potential links between CMV infection and various neurological disorders, the direct cause-effect relationship is not fully understood and several gaps in knowledge persist. Therefore, continued research is necessary to gain a better understanding of the role of CMV in neurological disorders and potential treatment avenues.
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Affiliation(s)
- Samira Sanami
- Abnormal Uterine Bleeding Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Shahnam Shamsabadi
- Department of Physiology, Physiology Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amir Dayhimi
- Department of Physiology, Physiology Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Pirhayati
- Psychiatric Department, Rasool Akram Hospital, Iran University of Medical Science, Tehran, Iran
| | - Sajjad Ahmad
- Department of Health and Biological Sciences, Abasyn University, Peshawar, Pakistan
- Department of Computer Sciences, Virginia Tech, Blacksburg, Virginia, USA
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
| | | | - Marjan Ajami
- National Nutrition and Food Technology Research Institute, School of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sara Hemati
- Department of Environmental Health Engineering, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Masoud Shirvani
- Department of Neurosurgery, Salamat-Farda Hospital, Tehran, Iran
| | - Ahmad Alagha
- Department of Neurosurgery, Salamat-Farda Hospital, Tehran, Iran
| | - Davood Abbarin
- Department of Neurosurgery, Salamat-Farda Hospital, Tehran, Iran
| | - Akram Alizadeh
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Hamidreza Pazoki-Toroudi
- Department of Physiology, Physiology Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
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Cantero JL, Atienza M, Sastre I, Bullido MJ. Human in vivo evidence of associations between herpes simplex virus and cerebral amyloid-beta load in normal aging. Alzheimers Res Ther 2024; 16:68. [PMID: 38570885 PMCID: PMC10988886 DOI: 10.1186/s13195-024-01437-4] [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: 02/17/2024] [Accepted: 03/25/2024] [Indexed: 04/05/2024]
Abstract
BACKGROUND Mounting data suggests that herpes simplex virus type 1 (HSV-1) is involved in the pathogenesis of AD, possibly instigating amyloid-beta (Aβ) accumulation decades before the onset of clinical symptoms. However, human in vivo evidence linking HSV-1 infection to AD pathology is lacking in normal aging, which may contribute to the elucidation of the role of HSV-1 infection as a potential AD risk factor. METHODS To shed light into this question, serum anti-HSV IgG levels were correlated with 18F-Florbetaben-PET binding to Aβ deposits and blood markers of neurodegeneration (pTau181 and neurofilament light chain) in cognitively normal older adults. Additionally, we investigated whether associations between anti-HSV IgG and AD markers were more evident in APOE4 carriers. RESULTS We showed that increased anti-HSV IgG levels are associated with higher Aβ load in fronto-temporal regions of cognitively normal older adults. Remarkably, these cortical regions exhibited abnormal patterns of resting state-functional connectivity (rs-FC) only in those individuals showing the highest levels of anti-HSV IgG. We further found that positive relationships between anti-HSV IgG levels and Aβ load, particularly in the anterior cingulate cortex, are moderated by the APOE4 genotype, the strongest genetic risk factor for AD. Importantly, anti-HSV IgG levels were unrelated to either subclinical cognitive deficits or to blood markers of neurodegeneration. CONCLUSIONS All together, these results suggest that HSV infection is selectively related to cortical Aβ deposition in normal aging, supporting the inclusion of cognitively normal older adults in prospective trials of antimicrobial therapy aimed at decreasing the AD risk in the aging population.
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Affiliation(s)
- Jose L Cantero
- Laboratory of Functional Neuroscience, Pablo de Olavide University, Ctra. de Utrera Km 1, Seville, 41013, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.
| | - Mercedes Atienza
- Laboratory of Functional Neuroscience, Pablo de Olavide University, Ctra. de Utrera Km 1, Seville, 41013, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
| | - Isabel Sastre
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital Universitario La Paz, IdiPAZ (Hospital Universitario La Paz - Universidad Autónoma de Madrid), Madrid, Spain
- Centro de Biología Molecular "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, Madrid, Spain
| | - María Jesús Bullido
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital Universitario La Paz, IdiPAZ (Hospital Universitario La Paz - Universidad Autónoma de Madrid), Madrid, Spain
- Centro de Biología Molecular "Severo Ochoa" (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, Madrid, Spain
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Rippee-Brooks MD, Wu W, Dong J, Pappolla M, Fang X, Bao X. Viral Infections, Are They a Trigger and Risk Factor of Alzheimer's Disease? Pathogens 2024; 13:240. [PMID: 38535583 PMCID: PMC10974111 DOI: 10.3390/pathogens13030240] [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: 02/01/2024] [Revised: 03/02/2024] [Accepted: 03/07/2024] [Indexed: 04/01/2024] Open
Abstract
Alzheimer's Disease (AD), a progressive and debilitating condition, is reported to be the most common type of dementia, with at least 55 million people believed to be currently affected. Many causation hypotheses of AD exist, yet the intriguing link between viral infection and its possible contribution to the known etiology of AD has become an attractive focal point of research for the field and a challenging study task. In this review, we will explore the historical perspective and milestones that led the field to investigate the viral connection to AD. Specifically, several viruses such as Herpes Simplex Virus 1 (HSV-1), Zika virus (ZIKV), and severe cute respiratory syndrome coronavirus 2 (SARS-CoV-2), along with several others mentioned, include the various viruses presently considered within the field. We delve into the strong evidence implicating these viruses in the development of AD such as the lytic replication and axonal transport of HSV-1, the various mechanisms of ZIKV neurotropism through the human protein Musashi-1 (MSI1), and the spread of SARS-CoV-2 through the transfer of the virus through the BBB endothelial cells to glial cells and then to neurons via transsynaptic transfer. We will also explore beyond these mere associations by carefully analyzing the potential mechanisms by which these viruses may contribute to AD pathology. This includes but is not limited to direct neuronal infections, the dysregulation of immune responses, and the impact on protein processing (Aβ42 and hyperphosphorylated tau). Controversies and challenges of the virus-AD relationship emerge as we tease out these potential mechanisms. Looking forward, we emphasize future directions, such as distinct questions and proposed experimentations to explore, that the field should take to tackle the remaining unanswered questions and the glaring research gaps that persist. Overall, this review aims to provide a comprehensive survey of the past, present, and future of the potential link between viral infections and their association with AD development while encouraging further discussion.
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Affiliation(s)
- Meagan D. Rippee-Brooks
- Microbiology and Immunology Graduate Program, Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Wenzhe Wu
- Department of Pediatrics, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Jianli Dong
- Department of Pathology, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Miguel Pappolla
- Department of Neurology and Mitchell Center for Neurodegenerative Diseases, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Xiang Fang
- Department of Neurology and Mitchell Center for Neurodegenerative Diseases, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Xiaoyong Bao
- Microbiology and Immunology Graduate Program, Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX 77550, USA
- Department of Pediatrics, The University of Texas Medical Branch, Galveston, TX 77550, USA
- The Institute of Translational Sciences, The University of Texas Medical Branch, Galveston, TX 77550, USA
- The Institute for Human Infections and Immunity, The University of Texas Medical Branch, Galveston, TX 77550, USA
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DePaula-Silva AB. The Contribution of Microglia and Brain-Infiltrating Macrophages to the Pathogenesis of Neuroinflammatory and Neurodegenerative Diseases during TMEV Infection of the Central Nervous System. Viruses 2024; 16:119. [PMID: 38257819 PMCID: PMC10819099 DOI: 10.3390/v16010119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
The infection of the central nervous system (CNS) with neurotropic viruses induces neuroinflammation and is associated with the development of neuroinflammatory and neurodegenerative diseases, including multiple sclerosis and epilepsy. The activation of the innate and adaptive immune response, including microglial, macrophages, and T and B cells, while required for efficient viral control within the CNS, is also associated with neuropathology. Under healthy conditions, resident microglia play a pivotal role in maintaining CNS homeostasis. However, during pathological events, such as CNS viral infection, microglia become reactive, and immune cells from the periphery infiltrate into the brain, disrupting CNS homeostasis and contributing to disease development. Theiler's murine encephalomyelitis virus (TMEV), a neurotropic picornavirus, is used in two distinct mouse models: TMEV-induced demyelination disease (TMEV-IDD) and TMEV-induced seizures, representing mouse models of multiple sclerosis and epilepsy, respectively. These murine models have contributed substantially to our understanding of the pathophysiology of MS and seizures/epilepsy following viral infection, serving as critical tools for identifying pharmacological targetable pathways to modulate disease development. This review aims to discuss the host-pathogen interaction during a neurotropic picornavirus infection and to shed light on our current understanding of the multifaceted roles played by microglia and macrophages in the context of these two complexes viral-induced disease.
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Affiliation(s)
- Ana Beatriz DePaula-Silva
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT 84112, USA
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15
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Liu Y, Xu W, Yang P, Liu X. Revealing Molecular Patterns of Alzheimer's Disease Risk Gene Expression Signatures in COVID-19 Brains. J Alzheimers Dis 2024; 101:31-48. [PMID: 39058446 DOI: 10.3233/jad-240609] [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: 07/28/2024]
Abstract
Background Various virus infections are known to predispose to Alzheimer's disease (AD), and a linkage between COVID-19 and AD has been established. COVID-19 infection modulates the gene expression of the genes implicated in progression of AD. Objective Determination of molecular patterns and codon usage and context analysis for the genes that are modulated during COVID-19 infection and are implicated in AD was the target of the study. Methods Our study employed a comprehensive array of research methods, including relative synonymous codon usage, Codon adaptation index analysis, Neutrality and parity analysis, Rare codon analyses, and codon context analysis. This meticulous approach was crucial in determining the molecular patterns present in genes up or downregulated during COVID-19 infection. Results G/C ending codons were preferred in upregulated genes while not in downregulated genes, and in both gene sets, longer genes have high expressivity. Similarly, T over A nucleotide was preferred, and selection was the major evolutionary force in shaping codon usage in both gene sets. Apart from stops codons, codons CGU - Arg, AUA - Ile, UUA - Leu, UCG - Ser, GUA - Val, and CGA - Arg in upregulated genes, while CUA - Leu, UCG - Ser, and UUA - Leu in downregulated genes were present below the 0.5%. Glutamine-initiated codon pairs have high residual values in upregulated genes. Identical codon pairs GAG-GAG and GUG-GUG were preferred in both gene sets. Conclusions The shared and unique molecular features in the up- and downregulated gene sets provide insights into the complex interplay between COVID-19 infection and AD. Further studies are required to elucidate the relationship of these molecular patterns with AD pathology.
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Affiliation(s)
- Yan Liu
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Third Hospital of Shanxi Medical University, Tongji Shanxi Hospital, Taiyuan, China
| | - Weiyue Xu
- Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Third Hospital of Shanxi Medical University, Tongji Shanxi Hospital, Taiyuan, China
| | - Pan Yang
- TEDA institute of Biological Science and Biotechnology, Nankai University, TEDA, Tianjin, China
| | - Xingshun Liu
- Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan, China
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16
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Duchesne S, Rousseau LS, Belzile-Marsolais F, Welch LA, Cournoyer B, Arseneau M, Lapierre V, Poulin SM, Potvin O, Hudon C. A Scoping Review of Alzheimers Disease Hypotheses: An Array of Uni- and Multi-Factorial Theories. J Alzheimers Dis 2024; 99:843-856. [PMID: 38788067 PMCID: PMC11191496 DOI: 10.3233/jad-230772] [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] [Accepted: 03/27/2024] [Indexed: 05/26/2024]
Abstract
Background There is a common agreement that Alzheimers disease (AD) is inherently complex; otherwise, a general disagreement remains on its etiological underpinning, with numerous alternative hypotheses having been proposed. Objective To perform a scoping review of original manuscripts describing hypotheses and theories of AD published in the past decades. Results We reviewed 131 original manuscripts that fulfilled our inclusion criteria out of more than 13,807 references extracted from open databases. Each entry was characterized as having a single or multifactorial focus and assigned to one of 15 theoretical groupings. Impact was tracked using open citation tools. Results Three stages can be discerned in terms of hypotheses generation, with three quarter of studies proposing a hypothesis characterized as being single-focus. The most important theoretical groupings were the Amyloid group, followed by Metabolism and Mitochondrial dysfunction, then Infections and Cerebrovascular. Lately, evidence towards Genetics and especially Gut/Brain interactions came to the fore. Conclusions When viewed together, these multi-faceted reports reinforce the notion that AD affects multiple sub-cellular, cellular, anatomical, and physiological systems at the same time but at varying degree between individuals. The challenge of providing a comprehensive view of all systems and their interactions remains, alongside ways to manage this inherent complexity.
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Affiliation(s)
- Simon Duchesne
- Department of Radiology and Nuclear Medicine, Université, Laval, Quebec City, QC, Canada
| | - Louis-Simon Rousseau
- CERVO Brain Research Centre, Quebec City, QC, Canada
- School of Psychology, Université, Laval, Quebec City, QC, Canada
| | - Florence Belzile-Marsolais
- CERVO Brain Research Centre, Quebec City, QC, Canada
- School of Psychology, Université, Laval, Quebec City, QC, Canada
| | - Laurie-Ann Welch
- CERVO Brain Research Centre, Quebec City, QC, Canada
- School of Psychology, Université, Laval, Quebec City, QC, Canada
| | | | | | - Véronick Lapierre
- CERVO Brain Research Centre, Quebec City, QC, Canada
- School of Psychology, Université, Laval, Quebec City, QC, Canada
| | | | - Olivier Potvin
- Quebec Heart and Lung Research Institute, Quebec City, QC, Canada
- CERVO Brain Research Centre, Quebec City, QC, Canada
| | - Carol Hudon
- CERVO Brain Research Centre, Quebec City, QC, Canada
- School of Psychology, Université, Laval, Quebec City, QC, Canada
- VITAM Research Centre, Quebec City, QC, Canada
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17
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Li Y, Li YJ, Zhu ZQ. To re-examine the intersection of microglial activation and neuroinflammation in neurodegenerative diseases from the perspective of pyroptosis. Front Aging Neurosci 2023; 15:1284214. [PMID: 38020781 PMCID: PMC10665880 DOI: 10.3389/fnagi.2023.1284214] [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: 08/28/2023] [Accepted: 10/27/2023] [Indexed: 12/01/2023] Open
Abstract
Neurodegenerative diseases (NDs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and motor neuron disease, are diseases characterized by neuronal damage and dysfunction. NDs are considered to be a multifactorial disease with diverse etiologies (immune, inflammatory, aging, genetic, etc.) and complex pathophysiological processes. Previous studies have found that neuroinflammation and typical microglial activation are important mechanisms of NDs, leading to neurological dysfunction and disease progression. Pyroptosis is a new mode involved in this process. As a form of programmed cell death, pyroptosis is characterized by the expansion of cells until the cell membrane bursts, resulting in the release of cell contents that activates a strong inflammatory response that promotes NDs by accelerating neuronal dysfunction and abnormal microglial activation. In this case, abnormally activated microglia release various pro-inflammatory factors, leading to the occurrence of neuroinflammation and exacerbating both microglial and neuronal pyroptosis, thus forming a vicious cycle. The recognition of the association between pyroptosis and microglia activation, as well as neuroinflammation, is of significant importance in understanding the pathogenesis of NDs and providing new targets and strategies for their prevention and treatment.
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Affiliation(s)
- Yuan Li
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- College of Anesthesiology, Zunyi Medical University, Zunyi, China
| | - Ying-Jie Li
- Department of General Surgery, Mianyang Hospital of Traditional Chinese Medicine, Mianyang, China
| | - Zhao-Qiong Zhu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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18
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Poddar NK, Khan A, Fatima F, Saxena A, Ghaley G, Khan S. Association of mTOR Pathway and Conformational Alterations in C-Reactive Protein in Neurodegenerative Diseases and Infections. Cell Mol Neurobiol 2023; 43:3815-3832. [PMID: 37665407 DOI: 10.1007/s10571-023-01402-z] [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: 06/02/2023] [Accepted: 08/15/2023] [Indexed: 09/05/2023]
Abstract
Inflammatory biomarkers have been very useful in detecting and monitoring inflammatory processes along with providing helpful information to select appropriate therapeutic strategies. C-reactive protein (CRP) is a nonspecific, but quite useful medical acute inflammatory biomarker and is associated with persistent chronic inflammatory processes. Several studies suggest that different levels of CRP are correlated with neurological disorders such as Alzheimer's disease (AD). However, dynamics of CRP levels have also been observed in virus/bacterial-related infections leading to inflammatory responses and this triggers mTOR-mediated pathways for neurodegeneration diseases. The biophysical structural transition from CRP to monomeric CRP (mCRP) and the significance of the ratio of CRP levels on the onset of symptoms associated with inflammatory response have been discussed. In addition, mTOR inhibitors act as immunomodulators by downregulating the expression of viral infection and can be explored as a potential therapy for neurological diseases.
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Affiliation(s)
- Nitesh Kumar Poddar
- Department of Biosciences, Manipal University Jaipur, Jaipur-Ajmer Express Highway, Dehmi Kalan, Near GVK Toll Plaza, Jaipur, Rajasthan, India, 303007.
| | - Arshma Khan
- Department of Biotechnology, Invertis University, Bareilly, Uttar Pradesh, India, 243123
| | - Falak Fatima
- Amity Institute of Biotechnology, Amity University, Uttar Pradesh, Noida, India, 201301
| | - Anshulika Saxena
- Department of Biosciences, Manipal University Jaipur, Jaipur-Ajmer Express Highway, Dehmi Kalan, Near GVK Toll Plaza, Jaipur, Rajasthan, India, 303007
| | - Garima Ghaley
- Department of Biosciences, Manipal University Jaipur, Jaipur-Ajmer Express Highway, Dehmi Kalan, Near GVK Toll Plaza, Jaipur, Rajasthan, India, 303007
| | - Shahanavaj Khan
- Department of Medical Lab Technology, Indian Institute of Health and Technology (IIHT), Deoband, Saharanpur, Uttar Pradesh, India, 247554.
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Pauwels EK, Boer GJ. Friends and Foes in Alzheimer's Disease. Med Princ Pract 2023; 32:313-322. [PMID: 37788649 PMCID: PMC10727688 DOI: 10.1159/000534400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 10/01/2023] [Indexed: 10/05/2023] Open
Abstract
Alzheimer's disease (AD) is a disabling neurodegenerative disease. The prognosis is poor, and currently there are no proven effective therapies. Most likely, the etiology is related to cerebral inflammatory processes that cause neuronal damage, resulting in dysfunction and apoptosis of nerve cells. Pathogens that evoke a neuroinflammatory response, collectively activate astrocytes and microglia, which contributes to the secretion of pro-inflammatory cytokines. This leads to the deposit of clustered fragments of beta-amyloid and misfolded tau proteins which do not elicit an adequate immune reaction. Apart from the function of astrocytes and microglia, molecular entities such as TREM2, SYK, C22, and C33 play a role in the physiopathology of AD. Furthermore, bacteria and viruses may trigger an overactive inflammatory response in the brain. Pathogens like Helicobacter pylori, Chlamydia pneumonia, and Porphyromonas gingivalis (known for low-grade infection in the oral cavity) can release gingipains, which are enzymes that can damage and destroy neurons. Chronic infection with Borrelia burgdorferi (the causative agent of Lyme disease) can co-localize with tau tangles and amyloid deposits. As for viral infections, herpes simplex virus 1, cytomegalovirus, and Epstein-Barr virus can play a role in the pathogenesis of AD. Present investigations have resulted in the development of antibodies that can clear the brain of beta-amyloid plaques. Trials with humanized aducanumab, lecanemab, and donanemab revealed limited success in AD patients. However, AD should be considered as a continuum in which the initial preclinical phase may take 10 or even 20 years. It is generally thought that this phase offers a window for efficacious treatment. Therefore, research is also focused on the identification of biomarkers for early AD detection. In this respect, the plasma measurement of neurofilament light chain in patients treated with hydromethylthionine mesylate may well open a new way to prevent the formation of tau tangles and represents the first treatment for AD at its roots.
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Affiliation(s)
- Ernest K.J. Pauwels
- Leiden University and Leiden University Medical Center, Leiden, The Netherlands
| | - Gerard J. Boer
- Netherlands Institute for Brain Research, Royal Academy of Arts and Sciences, Amsterdam, The Netherlands
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Feng S, Liu Y, Zhou Y, Shu Z, Cheng Z, Brenner C, Feng P. Mechanistic insights into the role of herpes simplex virus 1 in Alzheimer's disease. Front Aging Neurosci 2023; 15:1245904. [PMID: 37744399 PMCID: PMC10512732 DOI: 10.3389/fnagi.2023.1245904] [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: 06/27/2023] [Accepted: 08/21/2023] [Indexed: 09/26/2023] Open
Abstract
Alzheimer's Disease (AD) is an aging-associated neurodegenerative disorder, threatening millions of people worldwide. The onset and progression of AD can be accelerated by environmental risk factors, such as bacterial and viral infections. Human herpesviruses are ubiquitous infectious agents that underpin numerous inflammatory disorders including neurodegenerative diseases. Published studies concerning human herpesviruses in AD imply an active role HSV-1 in the pathogenesis of AD. This review will summarize the current understanding of HSV-1 infection in AD and highlight some barriers to advance this emerging field.
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Affiliation(s)
- Shu Feng
- Department of Diabetes and Cancer Metabolism, City of Hope National Medical Center, Duarte, CA, United States
| | - Yongzhen Liu
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, United States
| | - Yu Zhou
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, United States
| | - Zhenfeng Shu
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, United States
| | - Zhuxi Cheng
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, United States
- International Department, Beijing Bayi School, Beijing, China
| | - Charles Brenner
- Department of Diabetes and Cancer Metabolism, City of Hope National Medical Center, Duarte, CA, United States
| | - Pinghui Feng
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, United States
- Department of Molecular Microbiology and Immunology, Norris Comprehensive Cancer Center, Los Angeles, CA, United States
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Piotrowski SL, Tucker A, Jacobson S. The elusive role of herpesviruses in Alzheimer's disease: current evidence and future directions. NEUROIMMUNE PHARMACOLOGY AND THERAPEUTICS 2023; 2:253-266. [PMID: 38013835 PMCID: PMC10474380 DOI: 10.1515/nipt-2023-0011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 06/26/2023] [Indexed: 11/29/2023]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia. While pathologic hallmarks, such as extracellular beta-amyloid plaques, are well-characterized in affected individuals, the pathogenesis that causes plaque formation and eventual cognitive decline is not well understood. A recent resurgence of the decades-old "infectious hypothesis" has garnered increased attention on the potential role that microbes may play in AD. In this theory, it is thought that pathogens such as viruses may act as seeds for beta-amyloid aggregation, ultimately leading to plaques. Interest in the infectious hypothesis has also spurred further investigation into additional characteristics of viral infection that may play a role in AD progression, such as neuroinflammation, latency, and viral DNA integration. While a flurry of research in this area has been recently published, with herpesviruses being of particular interest, the role of pathogens in AD remains controversial. In this review, the insights gained thus far into the possible role of herpesviruses in AD are summarized. The challenges and potential future directions of herpesvirus research in AD and dementia are also discussed.
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Affiliation(s)
- Stacey L. Piotrowski
- Viral Immunology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Comparative Biomedical Scientist Training Program, National Institutes of Health, Bethesda, MD, USA
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
| | - Allison Tucker
- Viral Immunology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Steven Jacobson
- Viral Immunology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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22
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Ghorbani M, Ferreira D, Maioli S. A metagenomic study of gut viral markers in amyloid-positive Alzheimer's disease patients. Alzheimers Res Ther 2023; 15:141. [PMID: 37608325 PMCID: PMC10464408 DOI: 10.1186/s13195-023-01285-8] [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: 06/24/2023] [Accepted: 08/04/2023] [Indexed: 08/24/2023]
Abstract
BACKGROUND Mounting evidence suggests the involvement of viruses in the development and treatment of Alzheimer's disease (AD). However, there remains a significant research gap in metagenomic studies investigating the gut virome of AD patients, leaving gut viral dysbiosis in AD unexplored. This study aimed to fill this gap by conducting a metagenomics analysis of the gut virome in both amyloid-positive AD patients (Aβ + ADs) and healthy controls (HCs), with the objective of identifying viral signatures linked with AD. METHOD Whole-genome sequence (WGS) data from 65 human participants, including 30 Aβ + ADs and 35 HCs, was obtained from the database NCBI SRA (Bio Project: PRJEB47976). The Metaphlan3 pipeline and linear discriminant analysis effect size (LEfSe) analysis were utilized for the bioinformatics process and the detection of viral signatures, respectively. In addition, the Benjamini-Hochberg method was applied with a significance cutoff of 0.05 to evaluate the false discovery rate for all biomarkers identified by LEfSe. The CombiROC model was employed to determine the discriminatory power of the viral signatures identified by LEfSe. RESULTS Compared to HCs, the gut virome profiles of Aβ + ADs showed lower alpha diversity, indicating a lower bacteriophage richness. The Siphoviridae family was decreased in Aβ + ADs. Significant decreases of Lactococcus phages were found in Aβ + ADs, including bIL285, Lactococcus phage bIL286, Lactococcus phage bIL309, and Lactococcus phage BK5 T, Lactococcus phage BM13, Lactococcus phage P335 sensu lato, Lactococcus phage phiLC3, Lactococcus phage r1t, Lactococcus phage Tuc2009, Lactococcus phage ul36, and Lactococcus virus bIL67. The predictive combined model of these viral signatures obtained an area under the curve of 0.958 when discriminating Aβ + ADs from HCs. CONCLUSION This is the first study to identify distinct viral signatures in the intestine that can be used to effectively distinguish individuals with AD from HCs.
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Affiliation(s)
- Mahin Ghorbani
- Department of Dental Medicine, Karolinska Institute, Stockholm, Sweden.
| | - Daniel Ferreira
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
- Facultad de Ciencias de la Salud, Universidad Fernando Pessoa Canarias, Las Palmas, España
| | - Silvia Maioli
- Division of Neurogeriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
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Qian W, Zhou J, Duan L, Wang H, Xu S, Cao Y. m 6A methylation: a potential key player in understanding and treating COVID-2019 infection. Cell Death Discov 2023; 9:300. [PMID: 37596265 PMCID: PMC10439140 DOI: 10.1038/s41420-023-01580-1] [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: 03/12/2023] [Revised: 07/18/2023] [Accepted: 07/26/2023] [Indexed: 08/20/2023] Open
Abstract
Since its discovery in 2019, coronavirus disease 2019 (COVID-2019) spans a wide clinical spectrum from the asymptomatic stage, mild infection, to severe pneumonia. In patients with COVID-2019, factors such as advanced age, diabetes, or hypertension are associated with a significantly increased risk of severe diseases and death. Of note, the mechanisms underlying differences in the risk and symptoms of COVID-2019 among different populations are still poorly characterized. Accordingly, it is imperative to elucidate potential pathophysiological mechanisms and develop targeted therapeutic approaches for COVID-2019 infection. N6-methyladenosine (m6A) is one of the most common modifications in mammalian RNA transcripts and is widely found in messenger RNAs and some non-coding RNAs. It has been reported that m6A methylation modifications are present in viral RNA transcripts, which are of great significance for the regulation of the viral life cycle. Furthermore, m6A methylation has recently been found to be strongly associated with COVID-2019 infection. Therefore, this article reviews recent advances in studies related to the role of m6A methylation in COVID-2019 infection.
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Affiliation(s)
- Weiwei Qian
- Department of Emergency Medicine, Laboratory of Emergency Medicine, West China Hospital, and Disaster Medical Center, Sichuan University, Chengdu, 610044, Sichuan, China
- Department of Emergency,Shangjinnanfu Hospital, West China Hospital, Sichuan University, Chengdu, 610044, Sichuan, China
| | - Jian Zhou
- Department of Immunology, International Cancer Center, Shenzhen University Health Science Center, Shenzhen, 518061, Guangdong, China
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen, 518060, China
| | - Ligeng Duan
- Department of Emergency Medicine, Laboratory of Emergency Medicine, West China Hospital, and Disaster Medical Center, Sichuan University, Chengdu, 610044, Sichuan, China
| | - Haoyu Wang
- Department of Emergency Medicine, Laboratory of Emergency Medicine, West China Hospital, and Disaster Medical Center, Sichuan University, Chengdu, 610044, Sichuan, China
| | - Shuyun Xu
- Department of Emergency Medicine, Laboratory of Emergency Medicine, West China Hospital, and Disaster Medical Center, Sichuan University, Chengdu, 610044, Sichuan, China.
| | - Yu Cao
- Department of Emergency Medicine, Laboratory of Emergency Medicine, West China Hospital, and Disaster Medical Center, Sichuan University, Chengdu, 610044, Sichuan, China.
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Premkumar T, Sajitha Lulu S. Molecular crosstalk between COVID-19 and Alzheimer's disease using microarray and RNA-seq datasets: A system biology approach. Front Med (Lausanne) 2023; 10:1151046. [PMID: 37359008 PMCID: PMC10286240 DOI: 10.3389/fmed.2023.1151046] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 03/20/2023] [Indexed: 06/28/2023] Open
Abstract
Objective Coronavirus disease 2019 (COVID-19) is an infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The clinical and epidemiological analysis reported the association between SARS-CoV-2 and neurological diseases. Among neurological diseases, Alzheimer's disease (AD) has developed as a crucial comorbidity of SARS-CoV-2. This study aimed to understand the common transcriptional signatures between SARS-CoV-2 and AD. Materials and methods System biology approaches were used to compare the datasets of AD and COVID-19 to identify the genetic association. For this, we have integrated three human whole transcriptomic datasets for COVID-19 and five microarray datasets for AD. We have identified differentially expressed genes for all the datasets and constructed a protein-protein interaction (PPI) network. Hub genes were identified from the PPI network, and hub genes-associated regulatory molecules (transcription factors and miRNAs) were identified for further validation. Results A total of 9,500 differentially expressed genes (DEGs) were identified for AD and 7,000 DEGs for COVID-19. Gene ontology analysis resulted in 37 molecular functions, 79 cellular components, and 129 biological processes were found to be commonly enriched in AD and COVID-19. We identified 26 hub genes which includes AKT1, ALB, BDNF, CD4, CDH1, DLG4, EGF, EGFR, FN1, GAPDH, INS, ITGB1, ACTB, SRC, TP53, CDC42, RUNX2, HSPA8, PSMD2, GFAP, VAMP2, MAPK8, CAV1, GNB1, RBX1, and ITGA2B. Specific miRNA targets associated with Alzheimer's disease and COVID-19 were identified through miRNA target prediction. In addition, we found hub genes-transcription factor and hub genes-drugs interaction. We also performed pathway analysis for the hub genes and found that several cell signaling pathways are enriched, such as PI3K-AKT, Neurotrophin, Rap1, Ras, and JAK-STAT. Conclusion Our results suggest that the identified hub genes could be diagnostic biomarkers and potential therapeutic drug targets for COVID-19 patients with AD comorbidity.
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Chidambaram K. Identification of BACE-1 Inhibitors against Alzheimer’s Disease through E-Pharmacophore-Based Virtual Screening and Molecular Dynamics Simulation Studies: An Insilco Approach. Life (Basel) 2023; 13:life13040952. [PMID: 37109481 PMCID: PMC10142975 DOI: 10.3390/life13040952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/01/2023] [Accepted: 03/31/2023] [Indexed: 04/09/2023] Open
Abstract
Alzheimer is a severe memory and cognitive impairment neurodegenerative disease that is the most common cause of dementia worldwide and characterized by the pathological accumulation of tau protein and amyloid-beta peptides. In this study, we have developed E-pharmacophore modeling to screen the eMolecules database with the help of a reported co-crystal structure bound with Beta-Site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE-1). Flumemetamol, florbetaben, and florbetapir are currently approved drugs for use in the clinical diagnosis of Alzheimer’s disease. Despite the benefits of commercially approved drugs, there is still a need for novel diagnostic agents with enhanced physicochemical and pharmacokinetic properties compared to those currently used in clinical practice and research. In the E-pharmacophore modeling results, it is revealed that two aromatic rings (R19, R20), one donor (D12), and one acceptor (A8) are obtained, and also that similar pharmacophoric features of compounds are identified from pharmacophore-based virtual screening. The identified screened hits were filtered for further analyses using structure-based virtual screening and MM/GBSA. From the analyses, top hits such as ZINC39592220 and en1003sfl.46293 are selected based on their top docking scores (−8.182 and −7.184 Kcal/mol, respectively) and binding free energy (−58.803 and −56.951 Kcal/mol, respectively). Furthermore, a molecular dynamics simulation and MMPBSA study were performed, which revealed admirable stability and good binding free energy throughout the simulation period. Moreover, Qikprop results revealed that the selected, screened hits have good drug-likeness and pharmacokinetic properties. The screened hits ZINC39592220 and en1003sfl.46293 could be used to develop drug molecules against Alzheimer’s disease.
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Affiliation(s)
- Kumarappan Chidambaram
- Department of Pharmacology and Toxicology, College of Pharmacy, Al-Qara Campus, King Khalid University, Asir Province, Abha 61421, Saudi Arabia
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26
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Hulme J. COVID-19 and Diarylamidines: The Parasitic Connection. Int J Mol Sci 2023; 24:6583. [PMID: 37047556 PMCID: PMC10094973 DOI: 10.3390/ijms24076583] [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: 03/15/2023] [Revised: 03/28/2023] [Accepted: 03/30/2023] [Indexed: 04/05/2023] Open
Abstract
As emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants (Omicron) continue to outpace and negate combinatorial vaccines and monoclonal antibody therapies targeting the spike protein (S) receptor binding domain (RBD), the appetite for developing similar COVID-19 treatments has significantly diminished, with the attention of the scientific community switching to long COVID treatments. However, treatments that reduce the risk of "post-COVID-19 syndrome" and associated sequelae remain in their infancy, particularly as no established criteria for diagnosis currently exist. Thus, alternative therapies that reduce infection and prevent the broad range of symptoms associated with 'post-COVID-19 syndrome' require investigation. This review begins with an overview of the parasitic-diarylamidine connection, followed by the renin-angiotensin system (RAS) and associated angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSSR2) involved in SARS-CoV-2 infection. Subsequently, the ability of diarylamidines to inhibit S-protein binding and various membrane serine proteases associated with SARS-CoV-2 and parasitic infections are discussed. Finally, the roles of diarylamidines (primarily DIZE) in vaccine efficacy, epigenetics, and the potential amelioration of long COVID sequelae are highlighted.
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Affiliation(s)
- John Hulme
- Department of Bionano Technology, Gachon Bionano Research Institute, Gachon University, 1342 Sungnam-daero, Sujung-gu, Seongnam-si 461-701, Republic of Korea
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Arbez-Gindre C, Steele BR, Micha-Screttas M. Dendrimers in Alzheimer’s Disease: Recent Approaches in Multi-Targeting Strategies. Pharmaceutics 2023; 15:pharmaceutics15030898. [PMID: 36986759 PMCID: PMC10059864 DOI: 10.3390/pharmaceutics15030898] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/05/2023] [Accepted: 03/08/2023] [Indexed: 03/12/2023] Open
Abstract
Nanomaterials play an increasingly important role in current medicinal practice. As one of the most significant causes of human mortality, and one that is increasing year by year, Alzheimer’s disease (AD) has been the subject of a very great body of research and is an area in which nanomedicinal approaches show great promise. Dendrimers are a class of multivalent nanomaterials which can accommodate a wide range of modifications that enable them to be used as drug delivery systems. By means of suitable design, they can incorporate multiple functionalities to enable transport across the blood–brain barrier and subsequently target the diseased areas of the brain. In addition, a number of dendrimers by themselves often display therapeutic potential for AD. In this review, the various hypotheses relating to the development of AD and the proposed therapeutic interventions involving dendrimer–base systems are outlined. Special attention is focused on more recent results and on the importance of aspects such as oxidative stress, neuroinflammation and mitochondrial dysfunction in approaches to the design of new treatments.
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Controlling the Impact of Helicobacter pylori-Related Hyperhomocysteinemia on Neurodegeneration. Medicina (B Aires) 2023; 59:medicina59030504. [PMID: 36984505 PMCID: PMC10056452 DOI: 10.3390/medicina59030504] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
Helicobacter pylori infection consists a high global burden affecting more than 50% of the world’s population. It is implicated, beyond substantiated local gastric pathologies, i.e., peptic ulcers and gastric cancer, in the pathophysiology of several neurodegenerative disorders, mainly by inducing hyperhomocysteinemia-related brain cortical thinning (BCT). BCT has been advocated as a possible biomarker associated with neurodegenerative central nervous system disorders such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and/or glaucoma, termed as “ocular Alzheimer’s disease”. According to the infection hypothesis in relation to neurodegeneration, Helicobacter pylori as non-commensal gut microbiome has been advocated as trigger and/or mediator of neurodegenerative diseases, such as the development of Alzheimer’s disease. Among others, Helicobacter pylori-related inflammatory mediators, defensins, autophagy, vitamin D, dietary factors, role of probiotics, and some pathogenetic considerations including relevant involved genes are discussed within this opinion article. In conclusion, by controlling the impact of Helicobacter pylori-related hyperhomocysteinemia on neurodegenerative disorders might offer benefits, and additional research is warranted to clarify this crucial topic currently representing a major worldwide burden.
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Andrikopoulos N, Li Y, Nandakumar A, Quinn JF, Davis TP, Ding F, Saikia N, Ke PC. Zinc-Epigallocatechin-3-gallate Network-Coated Nanocomposites against the Pathogenesis of Amyloid-Beta. ACS APPLIED MATERIALS & INTERFACES 2023; 15:7777-7792. [PMID: 36724494 PMCID: PMC10037301 DOI: 10.1021/acsami.2c20334] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The aggregation of amyloid beta (Aβ) is a hallmark of Alzheimer's disease (AD), a major cause of dementia and an unmet challenge in modern medicine. In this study, we constructed a biocompatible metal-phenolic network (MPN) comprising a polyphenol epigallocatechin gallate (EGCG) scaffold coordinated by physiological Zn(II). Upon adsorption onto gold nanoparticles, the MPN@AuNP nanoconstruct elicited a remarkable potency against the amyloid aggregation and toxicity of Aβ in vitro. The superior performance of MPN@AuNP over EGCG@AuNP was attributed to the porosity and hence larger surface area of the MPN in comparison with that of EGCG alone. The atomic detail of Zn(II)-EGCG coordination was unraveled by density functional theory calculations and the structure and dynamics of Aβ aggregation modulated by the MPN were further examined by discrete molecular dynamics simulations. As MPN@AuNP also displayed a robust capacity to cross a blood-brain barrier model through the paracellular pathway, and given the EGCG's function as an anti-amyloidosis and antioxidation agent, this MPN-based strategy may find application in regulating the broad AD pathology beyond protein aggregation inhibition.
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Affiliation(s)
- Nicholas Andrikopoulos
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Yuhuan Li
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Liver Cancer Institute, Zhongshan Hospital, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Aparna Nandakumar
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - John F. Quinn
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Department of Chemical and Biological Engineering, Faculty of Engineering, Monash University, Clayton, VIC 3800, Australia
| | - Thomas P. Davis
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Nabanita Saikia
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Pu Chun Ke
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Nanomedicine Center, The Great Bay Area National Institute for Nanotechnology Innovation, 136 Kaiyuan Avenue, Guangzhou, 510700, China
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30
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Alraawi Z, Banerjee N, Mohanty S, Kumar TKS. Amyloidogenesis: What Do We Know So Far? Int J Mol Sci 2022; 23:ijms232213970. [PMID: 36430450 PMCID: PMC9695042 DOI: 10.3390/ijms232213970] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/01/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
The study of protein aggregation, and amyloidosis in particular, has gained considerable interest in recent times. Several neurodegenerative diseases, such as Alzheimer's (AD) and Parkinson's (PD) show a characteristic buildup of proteinaceous aggregates in several organs, especially the brain. Despite the enormous upsurge in research articles in this arena, it would not be incorrect to say that we still lack a crystal-clear idea surrounding these notorious aggregates. In this review, we attempt to present a holistic picture on protein aggregation and amyloids in particular. Using a chronological order of discoveries, we present the case of amyloids right from the onset of their discovery, various biophysical techniques, including analysis of the structure, the mechanisms and kinetics of the formation of amyloids. We have discussed important questions on whether aggregation and amyloidosis are restricted to a subset of specific proteins or more broadly influenced by the biophysiochemical and cellular environment. The therapeutic strategies and the significant failure rate of drugs in clinical trials pertaining to these neurodegenerative diseases have been also discussed at length. At a time when the COVID-19 pandemic has hit the globe hard, the review also discusses the plausibility of the far-reaching consequences posed by the virus, such as triggering early onset of amyloidosis. Finally, the application(s) of amyloids as useful biomaterials has also been discussed briefly in this review.
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Affiliation(s)
- Zeina Alraawi
- Department of Chemistry and Biochemistry, Fulbright College of Art and Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - Nayan Banerjee
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Srujana Mohanty
- Department of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata 741246, India
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31
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De Vlieger L, Vandenbroucke RE, Van Hoecke L. Recent insights into viral infections as a trigger and accelerator in alzheimer's disease. Drug Discov Today 2022; 27:103340. [PMID: 35987492 PMCID: PMC9385395 DOI: 10.1016/j.drudis.2022.103340] [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: 03/16/2022] [Revised: 07/08/2022] [Accepted: 08/12/2022] [Indexed: 11/16/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder for which only symptomatic medication is available, except for the recently FDA-approved aducanumab. This lack of effective treatment urges us to investigate alternative paths that might contribute to disease development. In light of the recent SARS-CoV-2 pandemic and the disturbing neurological complications seen in some patients, it is desirable to (re)investigate the viability of the viral infection theory claiming that a microbe could affect AD initiation and/or progression. Here, we review the most important evidence for this theory with a special focus on two viruses, namely HSV-1 and SARS-CoV-2. Moreover, we discuss the possible involvement of extracellular vesicles (EVs). This overview will contribute to a more rational approach of potential treatment strategies for AD patients.
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Affiliation(s)
- Lize De Vlieger
- Barriers in Inflammation Lab, VIB Center for Inflammation Research, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Roosmarijn E Vandenbroucke
- Barriers in Inflammation Lab, VIB Center for Inflammation Research, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
| | - Lien Van Hoecke
- Barriers in Inflammation Lab, VIB Center for Inflammation Research, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
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32
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Ferreira I, Rauter AP, Bandarra NM. Marine Sources of DHA-Rich Phospholipids with Anti-Alzheimer Effect. Mar Drugs 2022; 20:662. [PMID: 36354985 PMCID: PMC9695993 DOI: 10.3390/md20110662] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 07/29/2023] Open
Abstract
Alzheimer's disease (AD) is a complex and progressive disease, which affects millions of people around the world. Despite the many efforts over the years to find efficient therapeutics, there is no cure yet. Nonetheless, many compounds have been proven to decrease Alzheimer's symptoms. After a short overview of the hypotheses considered in AD drug development and the drugs approved for AD treatment, which lead to symptom release, we focus on the valorization of natural marine sources that decrease AD symptoms, particularly on docosahexaenoic acid (DHA), an important component in membrane phospholipids and the most abundant n-3 polyunsaturated fatty acids (PUFA) found in gray matter of the brain and in retina and on the DHA-containing phospholipids (DHA-PLs) present in marine sources, namely fish, krill, mollusks and in fisheries and aquaculture by-products. DHA-PLs' bioactivities are presented, namely their properties in anti-neurodegeneration, neuroinflammation, as anticancer agents, as well as their benefits to obesity and visual problems. Fisheries and aquaculture by-products are also highlighted as they have a high content of DHA and DHA-rich phospholipids, can be extracted by green methodologies and should be considered in a circular economy for a healthy sustainable future.
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Affiliation(s)
- Inês Ferreira
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- Division of Aquaculture, Upgrading and Bioprospecting, Portuguese Institute of the Sea and Atmosphere, 1495-165 Lisboa, Portugal
| | - Amélia P. Rauter
- Centro de Química Estrutural, Institute of Molecular Sciences, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Narcisa M. Bandarra
- Division of Aquaculture, Upgrading and Bioprospecting, Portuguese Institute of the Sea and Atmosphere, 1495-165 Lisboa, Portugal
- CIIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, 4050-123 Porto, Portugal
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Implications of Microorganisms in Alzheimer's Disease. Curr Issues Mol Biol 2022; 44:4584-4615. [PMID: 36286029 PMCID: PMC9600878 DOI: 10.3390/cimb44100314] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 09/23/2022] [Accepted: 09/28/2022] [Indexed: 11/20/2022] Open
Abstract
Alzheimer’s disease (AD) is a deadly brain degenerative disorder that leads to brain shrinkage and dementia. AD is manifested with hyperphosphorylated tau protein levels and amyloid beta (Aβ) peptide buildup in the hippocampus and cortex regions of the brain. The nervous tissue of AD patients also contains fungal proteins and DNA which are linked to bacterial infections, suggesting that polymicrobial infections also occur in the brains of those with AD. Both immunohistochemistry and next-generation sequencing (NGS) techniques were employed to assess fungal and bacterial infections in the brain tissue of AD patients and non-AD controls, with the most prevalent fungus genera detected in AD patients being Alternaria, Botrytis, Candida, and Malassezia. Interestingly, Fusarium was the most common genus detected in the control group. Both AD patients and controls were also detectable for Proteobacteria, followed by Firmicutes, Actinobacteria, and Bacteroides for bacterial infection. At the family level, Burkholderiaceae and Staphylococcaceae exhibited higher levels in the brains of those with AD than the brains of the control group. Accordingly, there is thought to be a viscous cycle of uncontrolled neuroinflammation and neurodegeneration in the brain, caused by agents such as the herpes simplex virus type 1 (HSV1), Chlamydophilapneumonia, and Spirochetes, and the presence of apolipoprotein E4 (APOE4), which is associated with an increased proinflammatory response in the immune system. Systemic proinflammatory cytokines are produced by microorganisms such as Cytomegalovirus, Helicobacter pylori, and those related to periodontal infections. These can then cross the blood–brain barrier (BBB) and lead to the onset of dementia. Here, we reviewed the relationship between the etiology of AD and microorganisms (such as bacterial pathogens, Herpesviridae viruses, and periodontal pathogens) according to the evidence available to understand the pathogenesis of AD. These findings might guide a targeted anti-inflammatory therapeutic approach to AD.
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Hospital-treated infections in early- and mid-life and risk of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis: A nationwide nested case-control study in Sweden. PLoS Med 2022; 19:e1004092. [PMID: 36107840 PMCID: PMC9477309 DOI: 10.1371/journal.pmed.1004092] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 08/15/2022] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Experimental observations have suggested a role of infection in the etiology of neurodegenerative disease. In human studies, however, it is difficult to disentangle whether infection is a risk factor or rather a comorbidity or secondary event of neurodegenerative disease. To this end, we examined the risk of 3 most common neurodegenerative diseases in relation to previous inpatient or outpatient episodes of hospital-treated infections. METHODS AND FINDINGS We performed a nested case-control study based on several national registers in Sweden. Cases were individuals newly diagnosed with Alzheimer's disease (AD), Parkinson's disease (PD), or amyotrophic lateral sclerosis (ALS) during 1970 to 2016 in Sweden, identified from the National Patient Register. For each case, 5 controls individually matched to the case on sex and year of birth were randomly selected from the general population. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) with adjustment for potential confounders, including sex, year of birth, area of residence, educational attainment, family history of neurodegenerative disease, and Charlson comorbidity index. Infections experienced within 5 years before diagnosis of neurodegenerative disease were excluded to reduce the influence of surveillance bias and reverse causation. The analysis included 291,941 AD cases (median age at diagnosis: 76.2 years; male: 46.6%), 103,919 PD cases (74.3; 55.1%), and 10,161 ALS cases (69.3; 56.8%). A hospital-treated infection 5 or more years earlier was associated with an increased risk of AD (OR = 1.16, 95% CI: 1.15 to 1.18, P < 0.001) and PD (OR = 1.04, 95% CI: 1.02 to 1.06, P < 0.001). Similar results were observed for bacterial, viral, and other infections and among different sites of infection including gastrointestinal and genitourinary infections. Multiple infections before age 40 conveyed the greatest risk of AD (OR = 2.62, 95% CI: 2.52 to 2.72, P < 0.001) and PD (OR = 1.41, 95% CI: 1.29 to 1.53, P < 0.001). The associations were primarily due to AD and PD diagnosed before 60 years (OR = 1.93, 95% CI: 1.89 to 1.98 for AD, P < 0.001; OR = 1.29, 95% CI: 1.22 to 1.36 for PD, P < 0.001), whereas no association was found for those diagnosed at 60 years or older (OR = 1.00, 95% CI: 0.98 to 1.01 for AD, P = 0.508; OR = 1.01, 95% CI: 0.99 to 1.03 for PD, P = 0.382). No association was observed for ALS (OR = 0.97, 95% CI: 0.92 to 1.03, P = 0.384), regardless of age at diagnosis. Excluding infections experienced within 10 years before diagnosis of neurodegenerative disease confirmed these findings. Study limitations include the potential misclassification of hospital-treated infections and neurodegenerative diseases due to incomplete coverage of the National Patient Register, as well as the residual confounding from unmeasured risk or protective factors for neurodegenerative diseases. CONCLUSIONS Hospital-treated infections, especially in early- and mid-life, were associated with an increased risk of AD and PD, primarily among AD and PD cases diagnosed before 60 years. These findings suggest that infectious events may be a trigger or amplifier of a preexisting disease process, leading to clinical onset of neurodegenerative disease at a relatively early age. However, due to the observational nature of the study, these results do not formally prove a causal link.
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Padhi D, Govindaraju T. Mechanistic Insights for Drug Repurposing and the Design of Hybrid Drugs for Alzheimer's Disease. J Med Chem 2022; 65:7088-7105. [PMID: 35559617 DOI: 10.1021/acs.jmedchem.2c00335] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The heterogeneity and complex nature of Alzheimer's disease (AD) is attributed to several genetic risk factors and molecular culprits. The slow pace and increasing failure rate of conventional drug discovery has led to the exploration of complementary strategies based on repurposing approved drugs to treat AD. Drug repurposing (DR) is a cost-effective, low-risk, and efficient approach for identifying novel therapeutic candidates for AD treatment. Similarly, hybrid drug design through the integration of distinct pharmacophores from known or failed drugs and natural products is an interesting strategy to target the multifactorial nature of AD. In this Perspective, we discuss the potential of DR and highlight promising drug candidates that can be advanced for clinical trials, backed by a detailed discussion on their plausible mechanisms of action. Our article fosters research on the hidden potential of DR and hybrid drug design with the goal of unravelling new drugs and targets to tackle AD.
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Affiliation(s)
- Dikshaa Padhi
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bengaluru, Karnataka 560064, India
| | - Thimmaiah Govindaraju
- Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur P.O., Bengaluru, Karnataka 560064, India
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Silva J, Patricio F, Patricio-Martínez A, Santos-López G, Cedillo L, Tizabi Y, Limón ID. Neuropathological Aspects of SARS-CoV-2 Infection: Significance for Both Alzheimer's and Parkinson's Disease. Front Neurosci 2022; 16:867825. [PMID: 35592266 PMCID: PMC9111171 DOI: 10.3389/fnins.2022.867825] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 04/14/2022] [Indexed: 01/08/2023] Open
Abstract
Evidence suggests that SARS-CoV-2 entry into the central nervous system can result in neurological and/or neurodegenerative diseases. In this review, routes of SARS-Cov-2 entry into the brain via neuroinvasive pathways such as transcribrial, ocular surface or hematogenous system are discussed. It is argued that SARS-Cov-2-induced cytokine storm, neuroinflammation and oxidative stress increase the risk of developing neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Further studies on the effects of SARS-CoV-2 and its variants on protein aggregation, glia or microglia activation, and blood-brain barrier are warranted.
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Affiliation(s)
- Jaime Silva
- Laboratorio de Neurofarmacología, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Felipe Patricio
- Laboratorio de Neurofarmacología, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Aleidy Patricio-Martínez
- Laboratorio de Neurofarmacología, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
- Facultad de Ciencias Biológicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Gerardo Santos-López
- Laboratorio de Biología Molecular y Virología, Centro de Investigación Biomédica de Oriente, Instituto Mexicano del Seguro Social, Atlixco, Mexico
| | - Lilia Cedillo
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Yousef Tizabi
- Department of Pharmacology, Howard University College of Medicine, Washington, DC, United States
| | - Ilhuicamina Daniel Limón
- Laboratorio de Neurofarmacología, Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
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Osorio C, Sfera A, Anton JJ, Thomas KG, Andronescu CV, Li E, Yahia RW, Avalos AG, Kozlakidis Z. Virus-Induced Membrane Fusion in Neurodegenerative Disorders. Front Cell Infect Microbiol 2022; 12:845580. [PMID: 35531328 PMCID: PMC9070112 DOI: 10.3389/fcimb.2022.845580] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/01/2022] [Indexed: 12/15/2022] Open
Abstract
A growing body of epidemiological and research data has associated neurotropic viruses with accelerated brain aging and increased risk of neurodegenerative disorders. Many viruses replicate optimally in senescent cells, as they offer a hospitable microenvironment with persistently elevated cytosolic calcium, abundant intracellular iron, and low interferon type I. As cell-cell fusion is a major driver of cellular senescence, many viruses have developed the ability to promote this phenotype by forming syncytia. Cell-cell fusion is associated with immunosuppression mediated by phosphatidylserine externalization that enable viruses to evade host defenses. In hosts, virus-induced immune dysfunction and premature cellular senescence may predispose to neurodegenerative disorders. This concept is supported by novel studies that found postinfectious cognitive dysfunction in several viral illnesses, including human immunodeficiency virus-1, herpes simplex virus-1, and SARS-CoV-2. Virus-induced pathological syncytia may provide a unified framework for conceptualizing neuronal cell cycle reentry, aneuploidy, somatic mosaicism, viral spreading of pathological Tau and elimination of viable synapses and neurons by neurotoxic astrocytes and microglia. In this narrative review, we take a closer look at cell-cell fusion and vesicular merger in the pathogenesis of neurodegenerative disorders. We present a "decentralized" information processing model that conceptualizes neurodegeneration as a systemic illness, triggered by cytoskeletal pathology. We also discuss strategies for reversing cell-cell fusion, including, TMEM16F inhibitors, calcium channel blockers, senolytics, and tubulin stabilizing agents. Finally, going beyond neurodegeneration, we examine the potential benefit of harnessing fusion as a therapeutic strategy in regenerative medicine.
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Affiliation(s)
- Carolina Osorio
- Department of Psychiatry, Loma Linda University, Loma Linda, CA, United States
| | - Adonis Sfera
- Department of Psychiatry, Loma Linda University, Loma Linda, CA, United States
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Jonathan J. Anton
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Karina G. Thomas
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Christina V. Andronescu
- Medical Anthropology – Department of Anthropology, Stanford University, Stanford, CA, United States
| | - Erica Li
- School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Rayan W. Yahia
- School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Andrea García Avalos
- Universidad Nacional Autónoma de México (UNAM), Facultad de Medicina Campus, Ciudad de Mexico, Mexico
| | - Zisis Kozlakidis
- International Agency for Research on Cancer (IARC), Lyon, France
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38
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Kell DB, Laubscher GJ, Pretorius E. A central role for amyloid fibrin microclots in long COVID/PASC: origins and therapeutic implications. Biochem J 2022; 479:537-559. [PMID: 35195253 PMCID: PMC8883497 DOI: 10.1042/bcj20220016] [Citation(s) in RCA: 115] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/08/2022] [Accepted: 02/09/2022] [Indexed: 12/15/2022]
Abstract
Post-acute sequelae of COVID (PASC), usually referred to as 'Long COVID' (a phenotype of COVID-19), is a relatively frequent consequence of SARS-CoV-2 infection, in which symptoms such as breathlessness, fatigue, 'brain fog', tissue damage, inflammation, and coagulopathies (dysfunctions of the blood coagulation system) persist long after the initial infection. It bears similarities to other post-viral syndromes, and to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Many regulatory health bodies still do not recognize this syndrome as a separate disease entity, and refer to it under the broad terminology of 'COVID', although its demographics are quite different from those of acute COVID-19. A few years ago, we discovered that fibrinogen in blood can clot into an anomalous 'amyloid' form of fibrin that (like other β-rich amyloids and prions) is relatively resistant to proteolysis (fibrinolysis). The result, as is strongly manifested in platelet-poor plasma (PPP) of individuals with Long COVID, is extensive fibrin amyloid microclots that can persist, can entrap other proteins, and that may lead to the production of various autoantibodies. These microclots are more-or-less easily measured in PPP with the stain thioflavin T and a simple fluorescence microscope. Although the symptoms of Long COVID are multifarious, we here argue that the ability of these fibrin amyloid microclots (fibrinaloids) to block up capillaries, and thus to limit the passage of red blood cells and hence O2 exchange, can actually underpin the majority of these symptoms. Consistent with this, in a preliminary report, it has been shown that suitable and closely monitored 'triple' anticoagulant therapy that leads to the removal of the microclots also removes the other symptoms. Fibrin amyloid microclots represent a novel and potentially important target for both the understanding and treatment of Long COVID and related disorders.
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Affiliation(s)
- Douglas B. Kell
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, U.K
- The Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Kemitorvet 200, 2800 Kgs Lyngby, Denmark
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch Private Bag X1 Matieland, 7602, South Africa
| | | | - Etheresia Pretorius
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch Private Bag X1 Matieland, 7602, South Africa
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39
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Zhang X, Liu Y, Deng J, Xia J, Zhang Q, Chen X, Liu R, Gao Y, Gao JM. Structurally Diverse Sesquiterpenoid Glycoside Esters from Pittosporum qinlingense with Anti-neuroinflammatory Activity. JOURNAL OF NATURAL PRODUCTS 2022; 85:115-126. [PMID: 34978437 DOI: 10.1021/acs.jnatprod.1c00544] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Thirteen new sesquiterpenoid glycoside esters, including 11 aromadendrane-type compounds, pitqinlingosides A-K (1-11), one cadinane-type compound, pitqinlingoside L (12), and one eudesmane-type compound, pitqinlingoside M (13), together with seven known analogues (14-20) were isolated from the twigs, fruits, and leaves of Pittosporum qinlingense. Structures were elucidated by analysis of spectroscopic data, gas chromatography mass spectrometry (GC-MS), and chemical methods. The absolute configuration was confirmed by single-crystal X-ray crystallography analysis or electronic circular dichroism spectra. Unusual glycoside esters are characterized by the presence of polyacylated β-d-fucopyranosyl, β-d-glucopyranosyl, and β-d-xylopyranosyl units. Pitqinlingosides A (1), B (2), D (4), and F (6), pittosporanoside A1 acetate (14), and pittosporanoside A1 (16) showed significant nitric oxide production inhibition in lipopolysaccharide (LPS)-induced BV-2 microglial cells with IC50 values ranging from 0.95 to 24.12 μM. Structure-activity relationships of the isolated compounds are discussed.
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Affiliation(s)
- Xiuyun Zhang
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Yao Liu
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Jili Deng
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Jiankai Xia
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Qiang Zhang
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Xin Chen
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Runze Liu
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Yuqi Gao
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
| | - Jin-Ming Gao
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, Shaanxi, People's Republic of China
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40
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Hunter P. Viral diseases and the brain: Long COVID puts the spotlight on how viral infections affect the brain: Long COVID puts the spotlight on how viral infections affect the brain. EMBO Rep 2022; 23:e54342. [PMID: 34842325 PMCID: PMC8728624 DOI: 10.15252/embr.202154342] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 11/17/2021] [Indexed: 01/07/2023] Open
Abstract
Various viruses can affect the brain directly or indirectly. The specter of Long COVID has focused research on how respiratory viruses can cause infection and inflammation of brain cells.
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41
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Tiwari D, Singh VK, Baral B, Pathak DK, Jayabalan J, Kumar R, Tapryal S, Jha HC. Indication of Neurodegenerative Cascade Initiation by Amyloid-like Aggregate-Forming EBV Proteins and Peptide in Alzheimer's Disease. ACS Chem Neurosci 2021; 12:3957-3967. [PMID: 34609141 DOI: 10.1021/acschemneuro.1c00584] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The neurotropic potential of the Epstein-Barr virus (EBV) was demonstrated quite recently; however, the mechanistic details are yet to be explored. Therefore, the effects of EBV infection in the neural milieu remain underexplored. Previous reports have suggested the potential role of virus-derived peptides in seeding the amyloid-β aggregation cascade, which lies at the center of Alzheimer's disease (AD) pathophysiology. However, no such study has been undertaken to explore the role of EBV peptides in AD. In our research, ∼100 EBV proteins were analyzed for their aggregation proclivity in silico using bioinformatic tools, followed by the prediction of 20S proteasomal cleavage sites using online algorithms NetChop ver. 3.1 and Pcleavage, thereby mimicking the cellular proteasomal cleavage activity generating short antigenic peptides of viral origin. Our study reports a high aggregate-forming tendency of a 12-amino-acid-long (146SYKHVFLSAFVY157) peptide derived from EBV glycoprotein M (EBV-gM). The in vitro analysis of aggregate formation done using Congo red and Thioflavin-S assays demonstrated dose- and time-dependent kinetics. Thereafter, Raman spectroscopy was used to validate the formation of secondary structures (α helix, β sheets) in the aggregates. Additionally, cytotoxicity assay revealed that even a low concentration of these aggregates has a lethal effect on neuroblastoma cells. The findings of this study provide insights into the mechanistic role of EBV in AD and open up new avenues to explore in the future.
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Affiliation(s)
- Deeksha Tiwari
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | - Vikas Kumar Singh
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Ajmer 305817, Rajasthan, India
| | - Budhadev Baral
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | - Devesh Kumar Pathak
- Discipline of Physics, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | - Jesumony Jayabalan
- Nano Science Laboratory, MSS, Raja Ramanna Centre for Advanced Technology, Indore 452013, India
- Homi Bhabha National Institute, Training School
Complex, Anushakti Nagar, Mumbai 400094, India
| | - Rajesh Kumar
- Discipline of Physics, Indian Institute of Technology Indore, Simrol, Indore 453552, India
- Centre for Advanced Electronics, Indian Institute of Technology Indore, Simrol, Indore 453552, India
| | - Suman Tapryal
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Ajmer 305817, Rajasthan, India
| | - Hem Chandra Jha
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol, Indore 453552, India
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42
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IKK2/NF-κB Activation in Astrocytes Reduces amyloid β Deposition: A Process Associated with Specific Microglia Polarization. Cells 2021; 10:cells10102669. [PMID: 34685649 PMCID: PMC8534251 DOI: 10.3390/cells10102669] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/29/2021] [Accepted: 10/04/2021] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is a common neurodegenerative disease that is accompanied by pronounced neuroinflammatory responses mainly characterized by marked microgliosis and astrogliosis. However, it remains open as to how different aspects of astrocytic and microglial activation affect disease progression. Previously, we found that microglia expansion in the spinal cord, initiated by IKK2/NF-κB activation in astrocytes, exhibits stage-dependent beneficial effects on the progression of amyotrophic lateral sclerosis. Here, we investigated the impact of NF-κB-initiated neuroinflammation on AD pathogenesis using the APP23 mouse model of AD in combination with conditional activation of IKK2/NF-κB signaling in astrocytes. We show that NF-κB activation in astrocytes triggers a distinct neuroinflammatory response characterized by striking astrogliosis as well as prominent microglial reactivity. Immunohistochemistry and Congo red staining revealed an overall reduction in the size and number of amyloid plaques in the cerebral cortex and hippocampus. Interestingly, isolated primary astrocytes and microglia cells exhibit specific marker gene profiles which, in the case of microglia, point to an enhanced plaque clearance capacity. In contrast, direct IKK2/NF-κB activation in microglia results in a pro-inflammatory polarization program. Our findings suggest that IKK2/NF-κB signaling in astrocytes may activate paracrine mechanisms acting on microglia function but also on APP processing in neurons.
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43
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Tyler KL. The Link Between Alzheimer Disease and Herpes Simplex Virus Infection: Better Late Than Never, or Better Never Than Late? Neurotherapeutics 2021; 18:2421-2424. [PMID: 34480291 PMCID: PMC8804014 DOI: 10.1007/s13311-021-01112-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2021] [Indexed: 10/20/2022] Open
Affiliation(s)
- Kenneth L Tyler
- University of Colorado School of Medicine, Neurology Mailstop B182, Research Complex-II, 12700 E. 19th Ave, Aurora, CO, 80045, USA.
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44
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Yong SJ, Yong MH, Teoh SL, Soga T, Parhar I, Chew J, Lim WL. The Hippocampal Vulnerability to Herpes Simplex Virus Type I Infection: Relevance to Alzheimer's Disease and Memory Impairment. Front Cell Neurosci 2021; 15:695738. [PMID: 34483839 PMCID: PMC8414573 DOI: 10.3389/fncel.2021.695738] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 07/20/2021] [Indexed: 12/24/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) as a possible infectious etiology in Alzheimer’s disease (AD) has been proposed since the 1980s. The accumulating research thus far continues to support the association and a possible causal role of HSV-1 in the development of AD. HSV-1 has been shown to induce neuropathological and behavioral changes of AD, such as amyloid-beta accumulation, tau hyperphosphorylation, as well as memory and learning impairments in experimental settings. However, a neuroanatomical standpoint of HSV-1 tropism in the brain has not been emphasized in detail. In this review, we propose that the hippocampal vulnerability to HSV-1 infection plays a part in the development of AD and amnestic mild cognitive impairment (aMCI). Henceforth, this review draws on human studies to bridge HSV-1 to hippocampal-related brain disorders, namely AD and aMCI/MCI. Next, experimental models and clinical observations supporting the neurotropism or predilection of HSV-1 to infect the hippocampus are examined. Following this, factors and mechanisms predisposing the hippocampus to HSV-1 infection are discussed. In brief, the hippocampus has high levels of viral cellular receptors, neural stem or progenitor cells (NSCs/NPCs), glucocorticoid receptors (GRs) and amyloid precursor protein (APP) that support HSV-1 infectivity, as well as inadequate antiviral immunity against HSV-1. Currently, the established diseases HSV-1 causes are mucocutaneous lesions and encephalitis; however, this review revises that HSV-1 may also induce and/or contribute to hippocampal-related brain disorders, especially AD and aMCI/MCI.
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Affiliation(s)
- Shin Jie Yong
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| | - Min Hooi Yong
- Department of Psychology, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia.,Aging Health and Well-being Research Centre, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| | - Seong Lin Teoh
- Department of Anatomy, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Tomoko Soga
- Jeffrey Cheah School of Medicine and Health Sciences, Brain Research Institute Monash Sunway, Monash University Malaysia, Subang Jaya, Malaysia
| | - Ishwar Parhar
- Jeffrey Cheah School of Medicine and Health Sciences, Brain Research Institute Monash Sunway, Monash University Malaysia, Subang Jaya, Malaysia
| | - Jactty Chew
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
| | - Wei Ling Lim
- Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia.,Aging Health and Well-being Research Centre, School of Medical and Life Sciences, Sunway University, Petaling Jaya, Malaysia
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45
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Danics K, Forrest SL, Kapas I, Erber I, Schmid S, Törő K, Majtenyi K, Kovacs GG. Neurodegenerative proteinopathies associated with neuroinfections. J Neural Transm (Vienna) 2021; 128:1551-1566. [PMID: 34223998 PMCID: PMC8255726 DOI: 10.1007/s00702-021-02371-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 06/20/2021] [Indexed: 01/23/2023]
Abstract
Infectious agents, including viruses and bacteria, are proposed to be involved in the pathogenesis of Alzheimer’s disease (AD). According to this hypothesis, these agents have capacity to evade the host immune system leading to chronic infection, inflammation, and subsequent deposition of Aβ and phosphorylated-tau in the brain. Co-existing proteinopathies and age-related pathologies are common in AD and the brains of elderly individuals, but whether these are also related to neuroinfections remain to be established. This study determined the prevalence and distribution of neurodegenerative proteinopathies in patients with infection-induced acute or chronic inflammation associated with herpes simplex virus (HSV) encephalitis (n = 13) and neurosyphilis (n = 23). The mean age at death in HSV patients was 53 ± 12 years (range 24–65 years) and survival was 9 days–6 years following initial infection. The mean age at death and survival in neurosyphilis patients was 60 ± 15 years (range 36–86 years) and 1–5 years, respectively. Neuronal tau-immunoreactivity and neurites were observed in 8 HSV patients and 19 neurosyphilis patients, and in approximately half of these, this was found in regions associated with inflammation and expanding beyond regions expected from the Braak stage of neurofibrillary degeneration. Five neurosyphilis patients had cortical ageing-related tau astrogliopathy. Aβ-plaques were found in 4 HSV patients and 11 neurosyphilis patients. Lewy bodies were observed in one HSV patient and two neurosyphilis patients. TDP-43 pathology was absent. These observations provide insights into deposition of neurodegenerative proteins in neuroinfections, which might have implications for COVID-19 patients with chronic and/or post-infectious neurological symptoms and encephalitis.
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Affiliation(s)
- Krisztina Danics
- Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary.,Neuropathology and Prion Disease Reference Center, Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Shelley L Forrest
- Dementia Research Centre, School of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, Australia.,Faculty of Medicine and Health, School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Istvan Kapas
- Department of Neurology, St. Janos Hospital, Budapest, Hungary
| | - Irene Erber
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Susanne Schmid
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Klára Törő
- Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Katalin Majtenyi
- Neuropathology and Prion Disease Reference Center, Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Gabor G Kovacs
- Tanz Centre for Research in Neurodegenerative Disease and Department of Laboratory Medicine and Pathobiology, University of Toronto, Krembil Discovery Tower, 60 Leonard Ave, Toronto, ON, M5T 0S8, Canada. .,Laboratory Medicine Program & Krembil Brain Institute, University Health Network, Toronto, ON, Canada.
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46
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Lukiw WJ, Arceneaux L, Li W, Bond T, Zhao Y. Gastrointestinal (GI)-Tract Microbiome Derived Neurotoxins and their Potential Contribution to Inflammatory Neurodegeneration in Alzheimer's Disease (AD). JOURNAL OF ALZHEIMER'S DISEASE & PARKINSONISM 2021; 11:525. [PMID: 34457996 PMCID: PMC8395586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The human gastrointestinal (GI)-tract microbiome is a rich, complex and dynamic source of microorganisms that possess a staggering diversity and complexity. Importantly there is a significant variability in microbial complexity even amongst healthy individuals-this has made it difficult to link specific microbial abundance patterns with age-related neurological disease. GI-tract commensal microorganisms are generally beneficial to human metabolism and immunity, however enterotoxigenic forms of microbes possess significant potential to secrete what are amongst the most neurotoxic and pro-inflammatory biopolymers known. These include toxic glycolipids such as lipopolysaccharide (LPS), enterotoxins, microbial-derived amyloids and small non-coding RNA. One major microbial species of the GI-tract microbiome, about ~100-fold more abundant than Escherichia coli in deep GI-tract regions is Bacteroides fragilis, an anaerobic, rod-shaped Gram-negative bacterium. B. fragilis can secrete: (i) a particularly potent, pro-inflammatory and unique LPS subtype (BF-LPS); and (ii) a zinc-metalloproteinase known as B. fragilis-toxin (BFT) or fragilysin. Ongoing studies indicate that BF-LPS and/or BFT disrupt paracellular-and transcellular-barriers by cleavage of intercellular-proteins resulting in 'leaky' barriers. These barriers: (i) become defective and more penetrable with aging and disease; and (ii) permit entry of microbiome-derived neurotoxins into the systemic-circulation from which they next transit the blood-brain barrier and gain access to the CNS. Here LPS accumulates and significantly alters homeostatic patterns of gene expression. The affinity of LPS for neuronal nuclei is significantly enhanced in the presence of amyloid beta 42 (Aβ42) peptides. Recent research on the appearance of the brain thanatomicrobiome at the time of death and the increasing likelihood of a complex brain microbiome are reviewed and discussed. This paper will also highlight some recent advances in this extraordinary research area that links the pro-inflammatory exudates of the GI-tract microbiome with innate-immune disturbances and inflammatory-signaling within the CNS with reference to Alzheimer's disease (AD) wherever possible.
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Affiliation(s)
- Walter J. Lukiw
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Department of Ophthalmology, LSU Health Sciences Center,
New Orleans, LA, United States,Department of Neurology, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Corresponding author: Dr. Walter J. Lukiw, LSU
Neuroscience Center, Louisiana State University Health Sciences Center, New
Orleans, LA, United States,
| | - Lisa Arceneaux
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States
| | - Wenhong Li
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Department of Pharmacology, School of Pharmacy, Jiangxi
University of Traditional Chinese Medicine (TCM), Nanchang, China
| | - Taylor Bond
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States
| | - Yuhai Zhao
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Department of Anatomy and Cell Biology, Louisiana State
University, New Orleans, LA, United States
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