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Shi R, Yu S, Larbi A, Pin Ng T, Lu Y. Specific and cumulative infection burden and mild cognitive impairment and dementia: A population-based study. Brain Behav Immun 2024; 121:155-164. [PMID: 39043350 DOI: 10.1016/j.bbi.2024.07.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Revised: 07/04/2024] [Accepted: 07/20/2024] [Indexed: 07/25/2024] Open
Abstract
Infection by pathogenic microbes is widely hypothesized to be a risk factor for the development of neurocognitive disorders and dementia, but evidence remains limited. We analyzed the association of seropositivity to 11 common pathogens and cumulative infection burden with neurocognitive disorder (mild cognitive impairment and dementia) in a population-based cohort of 475 older individuals (mean age = 67.6 y) followed up over 3-5 years for the risk of MCI-dementia. Specific seropositivities showed a preponderance of positive trends of association with MCI-dementia, including for Plasmodium, H. pylori, and RSV (p < 0.05), as well as Chickungunya, HSV-2, CMV and EBV (p > 0.05), while HSV-1 and HHV-6 showed equivocal or no associations, and Dengue and VZV showed negative associations (p < 0.05) with MCI-dementia. High infection burden (5 + cumulated infections) was significantly associated with an increased MCI-dementia risk in comparison with low infection burden (1-3 cumulative infections), adjusted for age, sex, and education. Intriguingly, for a majority (8 of 11) of pathogens, levels of antibody titers were significantly lower in those with MCI-dementia compared to cognitive normal individuals. Based on our observations, we postulate that individuals who are unable to mount strong immunological responses to infection by diverse microorganisms, and therefore more vulnerable to infection by greater numbers of different microbial pathogens or repeated infections to the same pathogen in the course of their lifetime are more likely to develop MCI or dementia. This hypothesis should be tested in more studies.
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Affiliation(s)
- Rong Shi
- Department of Medical Psychology and Ethics, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, China
| | - Shuyan Yu
- Department of Physiology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, China; Shandong Provincial Key Laboratory of Mental Disorders, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, China
| | - Anis Larbi
- Biology of Aging Laboratory, Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore; Geriatrics Division, Department of Medicine, Research Center on Aging, University of Sherbrooke, Sherbrooke, Quebec, Canada
| | - Tze Pin Ng
- Gerontology Research Programme, Department of Psychological Medicine, National University Health System, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yanxia Lu
- Department of Medical Psychology and Ethics, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, China.
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2
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Jones TB, Chu P, Wilkey B, Lynch L, Jentarra G. Regional Differences in Microbial Infiltration of Brain Tissue from Alzheimer's Disease Patients and Control Individuals. Brain Sci 2024; 14:677. [PMID: 39061418 PMCID: PMC11274863 DOI: 10.3390/brainsci14070677] [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: 06/12/2024] [Revised: 06/29/2024] [Accepted: 07/01/2024] [Indexed: 07/28/2024] Open
Abstract
Alzheimer's disease (AD) is characterized by cognitive decline and neuropathology including amyloid beta (Aβ) plaques and neurofibrillary tangles (tau). Factors initiating or driving these pathologies remain unclear, though microbes have been increasingly implicated. Our data and others' findings indicate that microbes may be common constituents of the brain. It is notable that Aβ and tau have antimicrobial properties, suggesting a response to microbes in the brain. We used 16S rRNA sequencing to compare major bacterial phyla in post-mortem tissues from individuals exhibiting a range of neuropathology and cognitive status in two brain regions variably affected in AD. Our data indicate that strong regional differences exist, driven in part by the varied presence of Proteobacteria and Firmicutes. We confirmed our data using ELISA of bacterial lipopolysaccharide (LPS) and lipoteichoic acid in the same brain tissue. We identified a potential association between the composition of phyla and the presence of neuropathology but not cognitive status. Declining cognition and increasing pathology correlated closely with serum LPS, but not brain levels of LPS, although brain LPS showed a strong negative correlation with cerebral amyloid angiopathy. Collectively, our data suggest a region-specific heterogeneity of microbial populations in brain tissue potentially associated with neurodegenerative pathology.
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Affiliation(s)
- T. Bucky Jones
- College of Graduate Studies, Midwestern University, Glendale, AZ 85308, USA; (T.B.J.); (P.C.); (L.L.)
- Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ 85308, USA;
| | - Ping Chu
- College of Graduate Studies, Midwestern University, Glendale, AZ 85308, USA; (T.B.J.); (P.C.); (L.L.)
| | - Brooke Wilkey
- Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ 85308, USA;
- School of Medicine, Creighton University, Phoenix, AZ 85012, USA
| | - Leigha Lynch
- College of Graduate Studies, Midwestern University, Glendale, AZ 85308, USA; (T.B.J.); (P.C.); (L.L.)
| | - Garilyn Jentarra
- College of Graduate Studies, Midwestern University, Glendale, AZ 85308, USA; (T.B.J.); (P.C.); (L.L.)
- Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ 85308, USA;
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3
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Negro-Demontel L, Maleki AF, Reich DS, Kemper C. The complement system in neurodegenerative and inflammatory diseases of the central nervous system. Front Neurol 2024; 15:1396520. [PMID: 39022733 PMCID: PMC11252048 DOI: 10.3389/fneur.2024.1396520] [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: 03/05/2024] [Accepted: 06/17/2024] [Indexed: 07/20/2024] Open
Abstract
Neurodegenerative and neuroinflammatory diseases, including Alzheimer's disease, Parkinson's disease, and multiple sclerosis, affect millions of people globally. As aging is a major risk factor for neurodegenerative diseases, the continuous increase in the elderly population across Western societies is also associated with a rising prevalence of these debilitating conditions. The complement system, a crucial component of the innate immune response, has gained increasing attention for its multifaceted involvement in the normal development of the central nervous system (CNS) and the brain but also as a pathogenic driver in several neuroinflammatory disease states. Although complement is generally understood as a liver-derived and blood or interstitial fluid operative system protecting against bloodborne pathogens or threats, recent research, particularly on the role of complement in the healthy and diseased CNS, has demonstrated the importance of locally produced and activated complement components. Here, we provide a succinct overview over the known beneficial and pathological roles of complement in the CNS with focus on local sources of complement, including a discussion on the potential importance of the recently discovered intracellularly active complement system for CNS biology and on infection-triggered neurodegeneration.
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Affiliation(s)
- Luciana Negro-Demontel
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, United States
- Department of Histology and Embryology, Faculty of Medicine, UDELAR, Montevideo, Uruguay
- Neuroinflammation and Gene Therapy Laboratory, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Adam F. Maleki
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, United States
- Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke (NINDS), NIH, Bethesda, MD, United States
| | - Daniel S. Reich
- Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke (NINDS), NIH, Bethesda, MD, United States
| | - Claudia Kemper
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, United States
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4
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Winford E, Lutshumba J, Martin BJ, Wilcock DM, Jicha GA, Nikolajczyk BS, Stowe AM, Bachstetter AD. Terminally differentiated effector memory T cells associate with cognitive and AD-related biomarkers in an aging-based community cohort. Immun Ageing 2024; 21:36. [PMID: 38867294 PMCID: PMC11167815 DOI: 10.1186/s12979-024-00443-2] [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: 11/21/2023] [Accepted: 05/31/2024] [Indexed: 06/14/2024]
Abstract
BACKGROUND AND PURPOSE The immune response changes during aging and the progression of Alzheimer's disease (AD) and related dementia (ADRD). Terminally differentiated effector memory T cells (called TEMRA) are important during aging and AD due to their cytotoxic phenotype and association with cognitive decline. However, it is not clear if the changes seen in TEMRAs are specific to AD-related cognitive decline specifically or are more generally correlated with cognitive decline. This study aimed to examine whether TEMRAs are associated with cognition and plasma biomarkers of AD, neurodegeneration, and neuroinflammation in a community-based cohort of older adults. METHODS Study participants from a University of Kentucky Alzheimer's Disease Research Center (UK-ADRC) community-based cohort of aging and dementia were used to test our hypothesis. There were 84 participants, 44 women and 40 men. Participants underwent physical examination, neurological examination, medical history, cognitive testing, and blood collection to determine plasma biomarker levels (Aβ42/Aβ40 ratio, total tau, Neurofilament Light chain (Nf-L), Glial Fibrillary Acidic Protein (GFAP)) and to isolate peripheral blood mononuclear cells (PBMCs). Flow cytometry was used to analyze PBMCs from study participants for effector and memory T cell populations, including CD4+ and CD8+ central memory T cells (TCM), Naïve T cells, effector memory T cells (TEM), and effector memory CD45RA+ T cells (TEMRA) immune cell markers. RESULTS CD8+ TEMRAs were positively correlated with Nf-L and GFAP. We found no significant difference in CD8+ TEMRAs based on cognitive scores and no associations between CD8+ TEMRAs and AD-related biomarkers. CD4+ TEMRAs were associated with cognitive impairment on the MMSE. Gender was not associated with TEMRAs, but it did show an association with other T cell populations. CONCLUSION These findings suggest that the accumulation of CD8+ TEMRAs may be a response to neuronal injury (Nf-L) and neuroinflammation (GFAP) during aging or the progression of AD and ADRD. As our findings in a community-based cohort were not clinically-defined AD participants but included all ADRDs, this suggests that TEMRAs may be associated with changes in systemic immune T cell subsets associated with the onset of pathology.
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Affiliation(s)
- Edric Winford
- Department of Neuroscience, University of Kentucky, 741 S. Limestone St. Rm B459, Lexington, KY, 40536, USA
| | - Jenny Lutshumba
- Department of Neuroscience, University of Kentucky, 741 S. Limestone St. Rm B459, Lexington, KY, 40536, USA
| | - Barbara J Martin
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Donna M Wilcock
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, Lexington, KY, USA
| | - Gregory A Jicha
- Department of Neurology, University of Kentucky, Lexington, KY, USA
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Barbara S Nikolajczyk
- Department of Pharmacology and Nutritional Science, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky, Lexington, KY, USA
| | - Ann M Stowe
- Department of Neuroscience, University of Kentucky, 741 S. Limestone St. Rm B459, Lexington, KY, 40536, USA
- Department of Neurology, University of Kentucky, Lexington, KY, USA
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Adam D Bachstetter
- Department of Neuroscience, University of Kentucky, 741 S. Limestone St. Rm B459, Lexington, KY, 40536, USA.
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA.
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY, USA.
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Kettunen P, Koistinaho J, Rolova T. Contribution of CNS and extra-CNS infections to neurodegeneration: a narrative review. J Neuroinflammation 2024; 21:152. [PMID: 38845026 PMCID: PMC11157808 DOI: 10.1186/s12974-024-03139-y] [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: 03/17/2024] [Accepted: 05/23/2024] [Indexed: 06/09/2024] Open
Abstract
Central nervous system infections have been suggested as a possible cause for neurodegenerative diseases, particularly sporadic cases. They trigger neuroinflammation which is considered integrally involved in neurodegenerative processes. In this review, we will look at data linking a variety of viral, bacterial, fungal, and protozoan infections to Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis and unspecified dementia. This narrative review aims to bring together a broad range of data currently supporting the involvement of central nervous system infections in the development of neurodegenerative diseases. The idea that no single pathogen or pathogen group is responsible for neurodegenerative diseases will be discussed. Instead, we suggest that a wide range of susceptibility factors may make individuals differentially vulnerable to different infectious pathogens and subsequent pathologies.
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Affiliation(s)
- Pinja Kettunen
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Jari Koistinaho
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.
| | - Taisia Rolova
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
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6
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James LM, Tsilibary EP, Wanberg EJ, Georgopoulos AP. Negative Association of Cognitive Performance With Blood Serum Neurotoxicity and Its Modulation by Human Herpes Virus 5 (HHV5) Seropositivity in Healthy Women. Neurosci Insights 2024; 19:26331055241258436. [PMID: 38827247 PMCID: PMC11143810 DOI: 10.1177/26331055241258436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 05/15/2024] [Indexed: 06/04/2024] Open
Abstract
Identification of early influences on cognitive decline is of paramount importance in order to stem the impacts of decrements in cognitive functioning and to potentially intervene. Thus, here we focused on 132 healthy adult women (age range 26-98 years) to (a) determine whether factors circulating in serum may exert neurotoxic effects in vitro, (b) evaluate associations between serum neurotoxicity and cognitive performance, and (c) assess the influence of human herpes virus (HHV) seroprevalence and other factors on apoptosis and cognitive performance. The results documented that the addition of serum from healthy adult women to neural cell cultures resulted in apoptosis, indicating the presence of circulating neurotoxic factors in the serum. Furthermore, apoptosis increased with age, and was associated with decreased cognitive performance. Stepwise regression evaluating the influence of 6 HHVs on apoptosis and cognitive function revealed that only HHV5 (cytomegalovirus; CMV) seropositivity was significantly associated with apoptosis and cognitive decline, controlling for age. These findings document neurotoxic effects of serum from healthy women across the adult lifespan and suggest a unique detrimental influence associated with CMV seropositivity.
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Affiliation(s)
- Lisa M James
- The Healthy Brain Aging Group, Brain Sciences Center, Department of Veterans Affairs Health Care System, Minneapolis, MN, USA
- Department of Neuroscience, University of Minnesota Medical School, Minneapolis, MN, USA
- Department of Psychiatry, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Effie-Photini Tsilibary
- The Healthy Brain Aging Group, Brain Sciences Center, Department of Veterans Affairs Health Care System, Minneapolis, MN, USA
- Department of Neuroscience, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Erik J Wanberg
- The Healthy Brain Aging Group, Brain Sciences Center, Department of Veterans Affairs Health Care System, Minneapolis, MN, USA
| | - Apostolos P Georgopoulos
- The Healthy Brain Aging Group, Brain Sciences Center, Department of Veterans Affairs Health Care System, Minneapolis, MN, USA
- Department of Neuroscience, University of Minnesota Medical School, Minneapolis, MN, USA
- Department of Psychiatry, University of Minnesota Medical School, Minneapolis, MN, USA
- Department of Neurology, University of Minnesota Medical School, Minneapolis, MN, USA
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7
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Biagio P, Isabella DF, Federica C, Elena S, Ivan G. Alzheimer's disease and herpes viruses: Current events and perspectives. Rev Med Virol 2024; 34:e2550. [PMID: 38801246 DOI: 10.1002/rmv.2550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 05/19/2024] [Accepted: 05/21/2024] [Indexed: 05/29/2024]
Abstract
Alzheimer's disease (AD) is a real and current scientific and societal challenge. Alzheimer's disease is characterised by a neurodegenerative neuroinflammatory process, but the etiopathogenetic mechanisms are still unclear. The possible infectious aetiology and potential involvement of Herpes viruses as triggers for the formation of extracellular deposits of amyloid beta (Aβ) peptide (amyloid plaques) and intraneuronal aggregates of hyperphosphorylated and misfold could be a possible explanation. In fact, the possible genetic interference of Herpes viruses with the genome of the host neuronal cell or the stimulation of the infection to a continuous immune response with a consequent chronic inflammation could constitute those mechanisms underlying the development of AD, with possible implications in the understanding and management of the disease. Herpes viruses could be significantly involved in the pathogenesis of AD and in particular, their ability to reactivate in particular conditions such as immunocompromise and immunosenescence, could explain the neurological damage characteristic of AD. Our review aims to evaluate the state of the art of knowledge and perspectives regarding the potential relationship between Herpes viruses and AD, in order to be able to identify the possible etiopathogenetic mechanisms and the possible therapeutic implications.
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Affiliation(s)
- Pinchera Biagio
- Division of Infectious Diseases, Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, Italy
| | - Di Filippo Isabella
- Division of Infectious Diseases, Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, Italy
| | - Cuccurullo Federica
- Division of Infectious Diseases, Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, Italy
| | - Salvatore Elena
- Division of Neurology, Department of Neuroscience Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
| | - Gentile Ivan
- Division of Infectious Diseases, Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, Italy
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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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Li Z, Wang H, Yin Y. Peripheral inflammation is a potential etiological factor in Alzheimer's disease. Rev Neurosci 2024; 35:99-120. [PMID: 37602685 DOI: 10.1515/revneuro-2023-0049] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/27/2023] [Indexed: 08/22/2023]
Abstract
Peripheral inflammation could constitute a risk factor for AD. This review summarizes the research related to peripheral inflammation that appears to have a relationship with Alzheimer's disease. We find there are significant associations between AD and peripheral infection induced by various pathogens, including herpes simplex virus type 1, cytomegalovirus, Epstein-Barr virus, human immunodeficiency virus, severe acute respiratory syndrome coronavirus 2, Porphyromonas gingivalis, Helicobacter pylori, and Toxoplasma gondii. Chronic inflammatory diseases are also reported to contribute to the pathophysiology of AD. The mechanisms by which peripheral inflammation affects the pathophysiology of AD are complex. Pathogen-derived neurotoxic molecule composition, disrupted BBB, and dysfunctional neurogenesis may all play a role in peripheral inflammation, promoting the development of AD. Anti-pathogenic medications and anti-inflammatory treatments are reported to decrease the risk of AD. Studies that could improve understanding the associations between AD and peripheral inflammation are needed. If our assumption is correct, early intervention against inflammation may be a potential method of preventing and treating AD.
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Affiliation(s)
- Ziyuan Li
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| | - Hui Wang
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
| | - Yafu Yin
- Department of Nuclear Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Kongjiang Road 1665, Yangpu District, Shanghai 200092, China
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10
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De Francesco MA. Herpesviridae, Neurodegenerative Disorders and Autoimmune Diseases: What Is the Relationship between Them? Viruses 2024; 16:133. [PMID: 38257833 PMCID: PMC10818483 DOI: 10.3390/v16010133] [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: 11/09/2023] [Revised: 12/06/2023] [Accepted: 01/15/2024] [Indexed: 01/24/2024] Open
Abstract
Alzheimer's disease and Parkinson's disease represent the most common forms of cognitive impairment. Multiple sclerosis is a chronic inflammatory disease of the central nervous system responsible for severe disability. An aberrant immune response is the cause of myelin destruction that covers axons in the brain, spinal cord, and optic nerves. Systemic lupus erythematosus is an autoimmune disease characterized by alteration of B cell activation, while Sjögren's syndrome is a heterogeneous autoimmune disease characterized by altered immune responses. The etiology of all these diseases is very complex, including an interrelationship between genetic factors, principally immune associated genes, and environmental factors such as infectious agents. However, neurodegenerative and autoimmune diseases share proinflammatory signatures and a perturbation of adaptive immunity that might be influenced by herpesviruses. Therefore, they might play a critical role in the disease pathogenesis. The aim of this review was to summarize the principal findings that link herpesviruses to both neurodegenerative and autoimmune diseases; moreover, briefly underlining the potential therapeutic approach of virus vaccination and antivirals.
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Affiliation(s)
- Maria Antonia De Francesco
- Department of Molecular and Translational Medicine, Institute of Microbiology, University of Brescia-ASST Spedali Civili, 25123 Brescia, Italy
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11
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Müller L, Di Benedetto S. Immunosenescence and Cytomegalovirus: Exploring Their Connection in the Context of Aging, Health, and Disease. Int J Mol Sci 2024; 25:753. [PMID: 38255826 PMCID: PMC10815036 DOI: 10.3390/ijms25020753] [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: 11/18/2023] [Revised: 12/29/2023] [Accepted: 01/04/2024] [Indexed: 01/24/2024] Open
Abstract
Aging induces numerous physiological alterations, with immunosenescence emerging as a pivotal factor. This phenomenon has attracted both researchers and clinicians, prompting profound questions about its implications for health and disease. Among the contributing factors, one intriguing actor in this complex interplay is human cytomegalovirus (CMV), a member of the herpesvirus family. Latent CMV infection exerts a profound influence on the aging immune system, potentially contributing to age-related diseases. This review delves into the intricate relationship between immunosenescence and CMV, revealing how chronic viral infection impacts the aging immune landscape. We explore the mechanisms through which CMV can impact both the composition and functionality of immune cell populations and induce shifts in inflammatory profiles with aging. Moreover, we examine the potential role of CMV in pathologies such as cardiovascular diseases, cancer, neurodegenerative disorders, COVID-19, and Long COVID. This review underlines the importance of understanding the complex interplay between immunosenescence and CMV. It offers insights into the pathophysiology of aging and age-associated diseases, as well as COVID-19 outcomes among the elderly. By unraveling the connections between immunosenescence and CMV, we gain a deeper understanding of aging's remarkable journey and the profound role that viral infections play in transforming the human immune system.
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Affiliation(s)
- Ludmila Müller
- Max Planck Institute for Human Development, Lentzeallee 94, 14195 Berlin, Germany
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12
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Fu J, Wei Q, Chen X, Lai X, Shang H. Analysis of the Association Between Pathogen Exposure and the Risk of Dementia. J Alzheimers Dis 2024; 100:961-972. [PMID: 38995782 DOI: 10.3233/jad-240073] [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: 07/14/2024]
Abstract
Background Previous research has suggested that pathogen infections may serve as potential contributors to dementia. Objective Consequently, the study aimed to evaluate whether pathogen exposure heightens the risk of dementia. Methods Between 2006 and 2010, a total of 8,144 individuals from the UK Biobank had data on pathogen antibodies and were included in the baseline assessment. Cox proportional hazard models were employed for the analysis. Results Out of the 8,144 participants, 107 eventually developed dementia, while 55 participants were diagnosed with Alzheimer's disease (AD). Multivariate Cox regression analysis revealed that the levels of pathogen antibody titers of EBV and C. trachomatis were associated with an increased risk of dementia/AD. The highest quartile of EBV EBNA-1 and EBV VCA p18, and the second quartile of H. pylori VacA significantly increased the risk of dementia compared lower quartile (EBV EBNA-1: HR = 1.938, p = 0.018; EBV VCA p18: HR = 1.824, p = 0.040; H. pylori VacA: HR = 1.890, p = 0.033). Besides, the highest quartile of EBV VCA p18 had a higher risk of AD compared lower quartile (HR = 2.755, p = 0.029). Conclusions The study demonstrated that exposure to EBV, H. pylori, and C. trachomatis substantially elevated the risk of dementia/AD. Despite the relatively widespread occurrence of EBV infection in the population, elevated pathogen antibody titers were still found to increase the risk of dementia/AD. Besides, since C. trachomatis and C. pneumoniae are quite homologous, this study found that trachomatis (C. trachomatis/C. pneumoniae) may be significantly associated with the risk of AD/dementia.
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Affiliation(s)
- Jiajia Fu
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Rare Disease Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Laboratory of Neurodegenerative Disorders, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Qianqian Wei
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Rare Disease Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Laboratory of Neurodegenerative Disorders, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xueping Chen
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Rare Disease Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Laboratory of Neurodegenerative Disorders, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xiaohui Lai
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Huifang Shang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Rare Disease Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Laboratory of Neurodegenerative Disorders, West China Hospital, Sichuan University, Chengdu, Sichuan, China
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13
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Gericke C, Kirabali T, Flury R, Mallone A, Rickenbach C, Kulic L, Tosevski V, Hock C, Nitsch RM, Treyer V, Ferretti MT, Gietl A. Early β-amyloid accumulation in the brain is associated with peripheral T cell alterations. Alzheimers Dement 2023; 19:5642-5662. [PMID: 37314431 DOI: 10.1002/alz.13136] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 06/15/2023]
Abstract
INTRODUCTION Fast and minimally invasive approaches for early diagnosis of Alzheimer's disease (AD) are highly anticipated. Evidence of adaptive immune cells responding to cerebral β-amyloidosis has raised the question of whether immune markers could be used as proxies for β-amyloid accumulation in the brain. METHODS Here, we apply multidimensional mass-cytometry combined with unbiased machine-learning techniques to immunophenotype peripheral blood mononuclear cells from a total of 251 participants in cross-sectional and longitudinal studies. RESULTS We show that increases in antigen-experienced adaptive immune cells in the blood, particularly CD45RA-reactivated T effector memory (TEMRA) cells, are associated with early accumulation of brain β-amyloid and with changes in plasma AD biomarkers in still cognitively healthy subjects. DISCUSSION Our results suggest that preclinical AD pathology is linked to systemic alterations of the adaptive immune system. These immunophenotype changes may help identify and develop novel diagnostic tools for early AD assessment and better understand clinical outcomes.
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Affiliation(s)
- Christoph Gericke
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
| | - Tunahan Kirabali
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
| | - Roman Flury
- Institute of Mathematics, University of Zurich, Zurich, Switzerland
| | - Anna Mallone
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Institute of Microbiology, ETHZ, Zurich, Switzerland
| | - Chiara Rickenbach
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
| | - Luka Kulic
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Roche Pharma Research and Early Development, Roche, Basel, Switzerland
| | - Vinko Tosevski
- Mass Cytometry Facility, University of Zurich, Zurich, Switzerland
| | - Christoph Hock
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Center for Prevention and Dementia Therapy, University of Zurich, Schlieren, Switzerland
- Neurimmune AG, Schlieren, Switzerland
| | - Roger M Nitsch
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Neurimmune AG, Schlieren, Switzerland
| | - Valerie Treyer
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Center for Prevention and Dementia Therapy, University of Zurich, Schlieren, Switzerland
- Department of Nuclear Medicine, University Hospital Zurich, Zurich, Switzerland
| | - Maria Teresa Ferretti
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Women's Brain Project, Guntershausen, Switzerland
| | - Anton Gietl
- Institute for Regenerative Medicine - IREM, University of Zurich, Schlieren, Switzerland
- Center for Prevention and Dementia Therapy, University of Zurich, Schlieren, Switzerland
- Psychiatric University Hospital Zurich (PUK), Zurich, Switzerland
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14
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Winford E, Lutshumba J, Martin BJ, Wilcock DM, Jicha GA, Nikolajczyk BS, Stowe AM, Bachstetter AD. Terminally differentiated effector memory T cells associate with cognitive and AD-related biomarkers in an aging-based community cohort. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.27.568812. [PMID: 38077088 PMCID: PMC10705256 DOI: 10.1101/2023.11.27.568812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2023]
Abstract
Background and Purpose The immune response changes during aging and the progression of Alzheimer's disease (AD) and related dementia (ADRD). Terminally differentiated effector memory T cells (called TEMRA) are important during aging and AD due to their cytotoxic phenotype and association with cognitive decline. However, it is not clear if the changes seen in TEMRAs are specific to AD-related cognitive decline specifically or are more generally correlated with cognitive decline. This study aimed to examine whether TEMRAs are associated with cognition and plasma biomarkers of AD, neurodegeneration, and neuroinflammation in a community-based cohort of older adults. Methods Study participants from a University of Kentucky Alzheimer's Disease Research Center (UK-ADRC) community-based cohort of aging and dementia were used to test our hypothesis. There were 84 participants, 44 women and 40 men. Participants underwent physical examination, neurological examination, medical history, cognitive testing, and blood collection to determine plasma biomarker levels (Aβ42/Aβ40 ratio, total tau, Neurofilament Light chain (Nf-L), Glial Fibrillary Acidic Protein (GFAP)) and to isolate peripheral blood mononuclear cells (PBMCs). Flow cytometry was used to analyze PBMCs from study participants for effector and memory T cell populations, including CD4+ and CD8+ central memory T cells (TCM), Naïve T cells, effector memory T cells (TEM), and effector memory CD45RA+ T cells (TEMRA) immune cell markers. Results CD8+ TEMRAs were positively correlated with Nf-L and GFAP. We found no significant difference in CD8+ TEMRAs based on cognitive scores and no associations between CD8+ TEMRAs and AD-related biomarkers. CD4+ TEMRAs were associated with cognitive impairment on the MMSE. Gender was not associated with TEMRAs, but it did show an association with other T cell populations. Conclusion These findings suggest that the accumulation of CD8+ TEMRAs may be a response to neuronal injury (Nf-L) and neuroinflammation (GFAP) during aging or the progression of AD and ADRD. As our findings in a community-based cohort were not clinically-defined AD participants but included all ADRDs, this suggests that TEMRAs may be associated with changes in systemic immune T cell subsets associated with the onset of pathology.
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Affiliation(s)
- Edric Winford
- Department of Neuroscience, University of Kentucky; Lexington, Kentucky, USA
| | - Jenny Lutshumba
- Department of Neuroscience, University of Kentucky; Lexington, Kentucky, USA
| | - Barbara J. Martin
- Sanders-Brown Center on Aging, University of Kentucky; Lexington, Kentucky, USA
| | - Donna M. Wilcock
- Sanders-Brown Center on Aging, University of Kentucky; Lexington, Kentucky, USA
- Department of Physiology, University of Kentucky, Lexington; Lexington, Kentucky, USA
| | - Gregory A. Jicha
- Department of Neurology, University of Kentucky; Lexington, Kentucky, USA
- Sanders-Brown Center on Aging, University of Kentucky; Lexington, Kentucky, USA
| | - Barbara S. Nikolajczyk
- Department of Pharmacology and Nutritional Science, and Barnstable Brown Diabetes and Obesity Center, University of Kentucky; Lexington, Kentucky, USA
| | - Ann M Stowe
- Department of Neuroscience, University of Kentucky; Lexington, Kentucky, USA
- Department of Neurology, University of Kentucky; Lexington, Kentucky, USA
- Sanders-Brown Center on Aging, University of Kentucky; Lexington, Kentucky, USA
| | - Adam D. Bachstetter
- Department of Neuroscience, University of Kentucky; Lexington, Kentucky, USA
- Sanders-Brown Center on Aging, University of Kentucky; Lexington, Kentucky, USA
- Spinal Cord and Brain Injury Research Center, University of Kentucky; Lexington, Kentucky, USA
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15
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Zhang Z, Duan Z, Cui Y. CD8 + T cells in brain injury and neurodegeneration. Front Cell Neurosci 2023; 17:1281763. [PMID: 38077952 PMCID: PMC10702747 DOI: 10.3389/fncel.2023.1281763] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 10/30/2023] [Indexed: 02/19/2024] Open
Abstract
The interaction between the peripheral immune system and the brain is increasingly being recognized as an important layer of neuroimmune regulation and plays vital roles in brain homeostasis as well as neurological disorders. As an important population of T-cell lymphocytes, the roles of CD8+ T cells in infectious diseases and tumor immunity have been well established. Recently, increasing number of complex functions of CD8+ T cells in brain disorders have been revealed. However, an advanced summary and discussion of the functions and mechanisms of CD8+ T cells in brain injury and neurodegeneration are still lacking. Here, we described the differentiation and function of CD8+ T cells, reviewed the involvement of CD8+ T cells in the regulation of brain injury including stroke and traumatic brain injury and neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD), and discussed therapeutic prospects and future study goals. Understanding these processes will promote the investigation of T-cell immunity in brain disorders and provide new intervention strategies for the treatment of brain injury and neurodegeneration.
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Affiliation(s)
- Zhaolong Zhang
- Department of Interventional Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Zhongying Duan
- Institute of Neuroregeneration and Neurorehabilitation, Qingdao University, Qingdao, Shandong, China
- Qingdao Medical College, Qingdao University, Qingdao, China
| | - Yu Cui
- Institute of Neuroregeneration and Neurorehabilitation, Qingdao University, Qingdao, Shandong, China
- Qingdao Medical College, Qingdao University, Qingdao, China
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16
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Bruno F, Abondio P, Bruno R, Ceraudo L, Paparazzo E, Citrigno L, Luiselli D, Bruni AC, Passarino G, Colao R, Maletta R, Montesanto A. Alzheimer's disease as a viral disease: Revisiting the infectious hypothesis. Ageing Res Rev 2023; 91:102068. [PMID: 37704050 DOI: 10.1016/j.arr.2023.102068] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 09/15/2023]
Abstract
Alzheimer's disease (AD) represents the most frequent type of dementia in elderly people. Two major forms of the disease exist: sporadic - the causes of which have not yet been fully understood - and familial - inherited within families from generation to generation, with a clear autosomal dominant transmission of mutations in Presenilin 1 (PSEN1), 2 (PSEN2) or Amyloid Precursors Protein (APP) genes. The main hallmark of AD consists of extracellular deposits of amyloid-beta (Aβ) peptide and intracellular deposits of the hyperphosphorylated form of the tau protein. An ever-growing body of research supports the viral infectious hypothesis of sporadic forms of AD. In particular, it has been shown that several herpes viruses (i.e., HHV-1, HHV-2, HHV-3 or varicella zoster virus, HHV-4 or Epstein Barr virus, HHV-5 or cytomegalovirus, HHV-6A and B, HHV-7), flaviviruses (i.e., Zika virus, Dengue fever virus, Japanese encephalitis virus) as well as Human Immunodeficiency Virus (HIV), hepatitis viruses (HAV, HBV, HCV, HDV, HEV), SARS-CoV2, Ljungan virus (LV), Influenza A virus and Borna disease virus, could increase the risk of AD. Here, we summarized and discussed these results. Based on these findings, significant issues for future studies are also put forward.
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Affiliation(s)
- Francesco Bruno
- Regional Neurogenetic Centre (CRN), Department of Primary Care, Azienda Sanitaria Provinciale Di Catanzaro, Viale A. Perugini, 88046 Lamezia Terme, CZ, Italy; Association for Neurogenetic Research (ARN), Lamezia Terme, CZ, Italy
| | - Paolo Abondio
- Laboratory of Ancient DNA, Department of Cultural Heritage, University of Bologna, Via degli Ariani 1, 48121 Ravenna, Italy.
| | - Rossella Bruno
- Sudent at the Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, 88050 Catanzaro, Italy
| | - Leognano Ceraudo
- Sudent at the Department of Medical and Surgical Sciences, University of Parma, 43121 Parma, Italy
| | - Ersilia Paparazzo
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Rende 87036, Italy
| | - Luigi Citrigno
- National Research Council (CNR) - Institute for Biomedical Research and Innovation - (IRIB), 87050 Mangone, Cosenza, Italy
| | - Donata Luiselli
- Laboratory of Ancient DNA, Department of Cultural Heritage, University of Bologna, Via degli Ariani 1, 48121 Ravenna, Italy
| | - Amalia C Bruni
- Regional Neurogenetic Centre (CRN), Department of Primary Care, Azienda Sanitaria Provinciale Di Catanzaro, Viale A. Perugini, 88046 Lamezia Terme, CZ, Italy; Association for Neurogenetic Research (ARN), Lamezia Terme, CZ, Italy
| | - Giuseppe Passarino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Rende 87036, Italy
| | - Rosanna Colao
- Regional Neurogenetic Centre (CRN), Department of Primary Care, Azienda Sanitaria Provinciale Di Catanzaro, Viale A. Perugini, 88046 Lamezia Terme, CZ, Italy
| | - Raffaele Maletta
- Regional Neurogenetic Centre (CRN), Department of Primary Care, Azienda Sanitaria Provinciale Di Catanzaro, Viale A. Perugini, 88046 Lamezia Terme, CZ, Italy; Association for Neurogenetic Research (ARN), Lamezia Terme, CZ, Italy
| | - Alberto Montesanto
- Department of Biology, Ecology and Earth Sciences, University of Calabria, Rende 87036, Italy.
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17
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Furman S, Green K, Lane TE. COVID-19 and the impact on Alzheimer's disease pathology. J Neurochem 2023:10.1111/jnc.15985. [PMID: 37850241 PMCID: PMC11024062 DOI: 10.1111/jnc.15985] [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: 08/18/2023] [Revised: 09/17/2023] [Accepted: 09/20/2023] [Indexed: 10/19/2023]
Abstract
Coronavirus disease 2019 (COVID-19) has rapidly escalated into a global pandemic that primarily affects older and immunocompromised individuals due to underlying clinical conditions and suppressed immune responses. Furthermore, COVID-19 patients exhibit a spectrum of neurological symptoms, indicating that COVID-19 can affect the brain in a variety of manners. Many studies, past and recent, suggest a connection between viral infections and an increased risk of neurodegeneration, raising concerns about the neurological effects of COVID-19 and the possibility that it may contribute to Alzheimer's disease (AD) onset or worsen already existing AD pathology through inflammatory processes given that both COVID-19 and AD share pathological features and risk factors. This leads us to question whether COVID-19 is a risk factor for AD and how these two conditions might influence each other. Considering the extensive reach of the COVID-19 pandemic and the devastating impact of the ongoing AD pandemic, their combined effects could have significant public health consequences worldwide.
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Affiliation(s)
- Susana Furman
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697
| | - Kim Green
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697
| | - Thomas E. Lane
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine 92697, USA
- Center for Virus Research, University of California, Irvine 92697, USA
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18
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Tiwari D, Srivastava G, Indari O, Tripathi V, Siddiqi MI, Jha HC. An in-silico insight into the predictive interaction of Apolipoprotein-E with Epstein-Barr virus proteins and their probable role in mediating Alzheimer's disease. J Biomol Struct Dyn 2023; 41:8918-8926. [PMID: 36307908 DOI: 10.1080/07391102.2022.2138978] [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: 08/03/2022] [Accepted: 10/16/2022] [Indexed: 10/31/2022]
Abstract
Recent reports suggest that persistent Epstein-Barr virus (EBV) infection and its recurrent reactivation could instigate the formation of proteinaceous plaques in the brain: a hallmark of Alzheimer's disease (AD). Interestingly, a major genetic risk factor of AD, the apolipoprotein E (ApoE), could also influence the outcome of EBV infection in an individual. The ApoE is believed to influence the proteinaceous plaque clearance from the brain, and its defective functioning could result in the aggregate deposition. The persistent presence of EBV infection in a genetically predisposed individual could create a perfect recipe for severe neurodegenerative consequences. Therefore, in the present study, we investigated the possible interactions between ApoE and various EBV proteins using computational tools. Our results showed possibly stable de-novo interactions between the C-terminal domain of ApoE3 and EBV proteins: EBV nuclear antigen-1 (EBNA1) and BamHI Z fragment leftward open reading frame-1 (BZLF1). The EBNA1 protein of EBV plays a crucial role in establishing latency and replication of the virus. Whereas BZLF1 is involved in the lytic replication cycle. The proposed interaction of EBV proteins at the ligand-binding site of ApoE3 on CTD could interfere with- its capability to sequester amyloid fragments and, hence their clearance from the brain giving rise to AD pathology. This study provides a new outlook on EBV's underexplored role in AD development and paves the way for novel avenues of investigation which could further our understanding of AD pathogenesis.Communicated by Ramaswamy H. Sarma[Figure: see text].
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Affiliation(s)
- Deeksha Tiwari
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Gaurava Srivastava
- Division of Biochemistry and Structural Biology, CSIR-CDRI, Lucknow, India
| | - Omkar Indari
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
| | - Vijay Tripathi
- Department of Molecular and Cellular Engineering, Jacob Institute of Biotechnology and Bioengineering, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, India
| | | | - Hem Chandra Jha
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Indore, India
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19
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Clement M. The association of microbial infection and adaptive immune cell activation in Alzheimer's disease. DISCOVERY IMMUNOLOGY 2023; 2:kyad015. [PMID: 38567070 PMCID: PMC10917186 DOI: 10.1093/discim/kyad015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 07/31/2023] [Accepted: 09/04/2023] [Indexed: 04/04/2024]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common form of dementia. Early symptoms include the loss of memory and mild cognitive ability; however, as the disease progresses, these symptoms can present with increased severity manifesting as mood and behaviour changes, disorientation, and a loss of motor/body control. AD is one of the leading causes of death in the UK, and with an ever-increasing ageing society, patient numbers are predicted to rise posing a significant global health emergency. AD is a complex neurophysiological disorder where pathology is characterized by the deposition and aggregation of misfolded amyloid-beta (Aβ)-protein that in-turn promotes excessive tau-protein production which together drives neuronal cell dysfunction, neuroinflammation, and neurodegeneration. It is widely accepted that AD is driven by a combination of both genetic and immunological processes with recent data suggesting that adaptive immune cell activity within the parenchyma occurs throughout disease. The mechanisms behind these observations remain unclear but suggest that manipulating the adaptive immune response during AD may be an effective therapeutic strategy. Using immunotherapy for AD treatment is not a new concept as the only two approved treatments for AD use antibody-based approaches to target Aβ. However, these have been shown to only temporarily ease symptoms or slow progression highlighting the urgent need for newer treatments. This review discusses the role of the adaptive immune system during AD, how microbial infections may be contributing to inflammatory immune activity and suggests how adaptive immune processes can pose as therapeutic targets for this devastating disease.
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Affiliation(s)
- Mathew Clement
- Division of Infection and Immunity, Systems Immunity University Research Institute, Cardiff University, Cardiff, UK
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20
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Dafre R, Wasnik P. Current Diagnostic and Treatment Methods of Alzheimer's Disease: A Narrative Review. Cureus 2023; 15:e45649. [PMID: 37868425 PMCID: PMC10589453 DOI: 10.7759/cureus.45649] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 09/20/2023] [Indexed: 10/24/2023] Open
Abstract
To diagnose and predict the possibility of Alzheimer's or a different kind of dementia, medical professionals employ tests that look at a patient's mental competence; however, such methods are impracticable. A reliable diagnosis at the start of treatment is essential for therapy. Except in situations with apparent genetic variations, most Alzheimer's patients lack a known etiology. Therefore, every Alzheimer's patient receives the same treatment plan, regardless of the etiology, which may or may not be successful in slowing or preventing the disease's progression. Tau pathology is further complicated by the amyloid buildup that arises from the cellular phase of Alzheimer's disease (AD). Alzheimer's is a degenerative, diverse, complicated, and incurable neurological disorder primarily affecting elderly individuals. The currently accepted drugs available for treating AD, which involve cholinesterase inhibitors and N-methyl-D-aspartate (NMDA)-receptor antagonists only provide temporary relief from symptoms. The neurological disorder primarily affecting elderly individuals is degenerative, diverse, complicated, and incurable. Accurate diagnosis is the most essential prerequisite before beginning therapy. Most Alzheimer's patients' causes are still unclear, except for instances where hereditary variations have been noted. The gut microbiota composition significantly influences AD and any age-associated neurological illness. Therapies are very useful in improving the cognitive functions of AD. New microbiota-based therapy alternatives may now be available due to the more recent connection between the altered gut microbiome and neurodegeneration through the gut microbiota-brain axis.
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Affiliation(s)
- Rajshri Dafre
- Health Science, Jawaharlal Nehru Medical College, Wardha, IND
| | - Praful Wasnik
- Medicine, Jawaharlal Nehru Medical College, Wardha, IND
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21
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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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Fulop T, Ramassamy C, Lévesque S, Frost EH, Laurent B, Lacombe G, Khalil A, Larbi A, Hirokawa K, Desroches M, Rodrigues S, Bourgade K, Cohen AA, Witkowski JM. Viruses - a major cause of amyloid deposition in the brain. Expert Rev Neurother 2023; 23:775-790. [PMID: 37551672 DOI: 10.1080/14737175.2023.2244162] [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: 04/01/2023] [Accepted: 07/31/2023] [Indexed: 08/09/2023]
Abstract
INTRODUCTION Clinically, Alzheimer's disease (AD) is a syndrome with a spectrum of various cognitive disorders. There is a complete dissociation between the pathology and the clinical presentation. Therefore, we need a disruptive new approach to be able to prevent and treat AD. AREAS COVERED In this review, the authors extensively discuss the evidence why the amyloid beta is not the pathological cause of AD which makes therefore the amyloid hypothesis not sustainable anymore. They review the experimental evidence underlying the role of microbes, especially that of viruses, as a trigger/cause for the production of amyloid beta leading to the establishment of a chronic neuroinflammation as the mediator manifesting decades later by AD as a clinical spectrum. In this context, the emergence and consequences of the infection/antimicrobial protection hypothesis are described. The epidemiological and clinical data supporting this hypothesis are also analyzed. EXPERT OPINION For decades, we have known that viruses are involved in the pathogenesis of AD. This discovery was ignored and discarded for a long time. Now we should accept this fact, which is not a hypothesis anymore, and stimulate the research community to come up with new ideas, new treatments, and new concepts.
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Affiliation(s)
- Tamas Fulop
- Research Center on Aging, Centre Intégré Universitaire de Santé Et Services Sociaux de l'Estrie-Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Department of Medicine, Division of Geriatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | | | - Simon Lévesque
- CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada
- Département de Microbiologie Et Infectiologie, Faculté de Médecine Et des Sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Eric H Frost
- Département de Microbiologie Et Infectiologie, Faculté de Médecine Et des Sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Benoit Laurent
- Research Center on Aging, Centre Intégré Universitaire de Santé Et Services Sociaux de l'Estrie-Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Department of Biochemistry and Functional Genomics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Guy Lacombe
- Research Center on Aging, Centre Intégré Universitaire de Santé Et Services Sociaux de l'Estrie-Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Department of Medicine, Division of Geriatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Abedelouahed Khalil
- Research Center on Aging, Centre Intégré Universitaire de Santé Et Services Sociaux de l'Estrie-Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
- Department of Medicine, Division of Geriatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Anis Larbi
- Department of Medicine, Division of Geriatrics, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Katsuiku Hirokawa
- Department of Pathology, Institute of Health and Life Science, Tokyo Medical Dental University, Tokyo and Nito-Memory Nakanosogo Hospital, Tokyo, Japan
| | - Mathieu Desroches
- MathNeuro Team, Inria Sophia Antipolis Méditerranée, Biot, France
- Université Côte d'Azur, Nice, France
| | - Serafim Rodrigues
- Ikerbasque, BCAM, the Basque Foundation for Science and BCAM - The Basque Center for Applied Mathematics, Bilbao, Spain
| | - Karine Bourgade
- Research Center on Aging, Centre Intégré Universitaire de Santé Et Services Sociaux de l'Estrie-Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Alan A Cohen
- Department of Environmental Health Sciences, Butler Columbia Aging Center, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Jacek M Witkowski
- Department of Pathophysiology, Medical University of Gdansk, Gdansk, Poland
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23
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Aimola G, Wight DJ, Flamand L, Kaufer BB. Excision of Integrated Human Herpesvirus 6A Genomes Using CRISPR/Cas9 Technology. Microbiol Spectr 2023; 11:e0076423. [PMID: 36926973 PMCID: PMC10100985 DOI: 10.1128/spectrum.00764-23] [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: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 03/18/2023] Open
Abstract
Human herpesviruses 6A and 6B are betaherpesviruses that can integrate their genomes into the telomeres of latently infected cells. Integration can also occur in germ cells, resulting in individuals who harbor the integrated virus in every cell of their body and can pass it on to their offspring. This condition is termed inherited chromosomally integrated HHV-6 (iciHHV-6) and affects about 1% of the human population. The integrated HHV-6A/B genome can reactivate in iciHHV-6 patients and in rare cases can also cause severe diseases including encephalitis and graft-versus-host disease. Until now, it has remained impossible to prevent virus reactivation or remove the integrated virus genome. Therefore, we developed a system that allows the removal of HHV-6A from the host telomeres using the CRISPR/Cas9 system. We used specific guide RNAs (gRNAs) targeting the direct repeat region at the ends of the viral genome to remove the virus from latently infected cells generated in vitro and iciHHV-6A patient cells. Fluorescence-activated cell sorting (FACS), quantitative PCR (qPCR), and fluorescence in situ hybridization (FISH) analyses revealed that the virus genome was efficiently excised and lost in most cells. Efficient excision was achieved with both constitutive and transient expression of Cas9. In addition, reverse transcription-qPCR (RT-qPCR) revealed that the virus genome did not reactivate upon excision. Taken together, our data show that our CRISPR/Cas9 approach allows efficient removal of the integrated virus genome from host telomeres. IMPORTANCE Human herpesvirus 6 (HHV-6) infects almost all humans and integrates into the telomeres of latently infected cells to persist in the host for life. In addition, HHV-6 can also integrate into the telomeres of germ cells, which results in about 80 million individuals worldwide who carry the virus in every cell of their body and can pass it on to their offspring. In this study, we develop the first system that allows excision of the integrated HHV-6 genome from host telomeres using CRISPR/Cas9 technology. Our data revealed that the integrated HHV-6 genome can be efficiently removed from the telomeres of latently infected cells and cells of patients harboring the virus in their germ line. Virus removal could be achieved with both stable and transient Cas9 expression, without inducing viral reactivation.
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Affiliation(s)
- Giulia Aimola
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
| | - Darren J. Wight
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
| | - Louis Flamand
- Division of Infectious and Immune Diseases, CHU de Quebec Research Center-Laval University, Québec, Canada
- Department of Microbiology, Infectious Disease and Immunology, Faculty of Medicine, Laval University, Québec, Canada
| | - Benedikt B. Kaufer
- Institut für Virologie, Freie Universität Berlin, Berlin, Germany
- Veterinary Centre for Resistance Research (TZR), Freie Universität Berlin, Berlin, Germany
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24
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Hui BSM, Zhi LR, Retinasamy T, Arulsamy A, Law CSW, Shaikh MF, Yeong KY. The Role of Interferon-α in Neurodegenerative Diseases: A Systematic Review. J Alzheimers Dis 2023; 94:S45-S66. [PMID: 36776068 PMCID: PMC10473139 DOI: 10.3233/jad-221081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2022] [Indexed: 02/10/2023]
Abstract
BACKGROUND Neurodegenerative diseases (NDs) impose significant financial and healthcare burden on populations all over the world. The prevalence and incidence of NDs have been observed to increase dramatically with age. Hence, the number of reported cases is projected to increase in the future, as life spans continues to rise. Despite this, there is limited effective treatment against most NDs. Interferons (IFNs), a family of cytokines, have been suggested as a promising therapeutic target for NDs, particularly IFN-α, which governs various pathological pathways in different NDs. OBJECTIVE This systematic review aimed to critically appraise the currently available literature on the pathological role of IFN-α in neurodegeneration/NDs. METHODS Three databases, Scopus, PubMed, and Ovid Medline, were utilized for the literature search. RESULTS A total of 77 journal articles were selected for critical evaluation, based on the inclusion and exclusion criteria. The studies selected and elucidated in this current systematic review have showed that IFN-α may play a deleterious role in neurodegenerative diseases through its strong association with the inflammatory processes resulting in mainly neurocognitive impairments. IFN-α may be displaying its neurotoxic function via various mechanisms such as abnormal calcium mineralization, activation of STAT1-dependent mechanisms, and increased quinolinic acid production. CONCLUSION The exact role IFN-α in these neurodegenerative diseases have yet to be determine due to a lack in more recent evidence, thereby creating a variability in the role of IFN-α. Future investigations should thus be conducted, so that the role played by IFN-α in neurodegenerative diseases could be delineated.
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Affiliation(s)
- Brendan Su Mee Hui
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Johor Baru, Johor, Malaysia
| | - Lee Rui Zhi
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Johor Baru, Johor, Malaysia
| | - Thaarvena Retinasamy
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Alina Arulsamy
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | | | - Mohd. Farooq Shaikh
- Neuropharmacology Research Laboratory, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
- School of Dentistry and Medical Sciences, Charles Sturt University, Orange, NSW, Australia
- Department of Neuroscience, Central Clinical School, Monash University, The Alfred Hospital, Melbourne, VIC, Australia
| | - Keng Yoon Yeong
- School of Science, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
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25
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Emery DC, Davies M, Cerajewska TL, Taylor J, Hazell M, Paterson A, Allen-Birt SJ, West NX. High resolution 16S rRNA gene Next Generation Sequencing study of brain areas associated with Alzheimer's and Parkinson's disease. Front Aging Neurosci 2022; 14:1026260. [PMID: 36570533 PMCID: PMC9780557 DOI: 10.3389/fnagi.2022.1026260] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/02/2022] [Indexed: 12/13/2022] Open
Abstract
Introduction Alzheimer's (AD) and Parkinson's disease (PD) are neurodegenerative conditions characterized by incremental deposition of β-amyloid (Aβ) and α-synuclein in AD and PD brain, respectively, in relatively conserved patterns. Both are associated with neuroinflammation, with a proposed microbial component for disease initiation and/or progression. Notably, Aβ and α-synuclein have been shown to possess antimicrobial properties. There is evidence for bacterial presence within the brain, including the oral pathobiont Porphyromonas gingivalis, with cognitive impairment and brain pathology being linked to periodontal (gum) disease and gut dysbiosis. Methods Here, we use high resolution 16S rRNA PCR-based Next Generation Sequencing (16SNGS) to characterize bacterial composition in brain areas associated with the early, intermediate and late-stage of the diseases. Results and discussion This study reveals the widespread presence of bacteria in areas of the brain associated with AD and PD pathology, with distinctly different bacterial profiles in blood and brain. Brain area profiles were overall somewhat similar, predominantly oral, with some bacteria subgingival and oronasal in origin, and relatively comparable profiles in AD and PD brain. However, brain areas associated with early disease development, such as the locus coeruleus, were substantially different in bacterial DNA content compared to areas affected later in disease etiology.
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Affiliation(s)
| | | | | | | | - Mae Hazell
- Translational Health Sciences, Learning and Research, Bristol Medical School, Southmead Hospital, Bristol, United Kingdom
| | - Alex Paterson
- School of Biological Sciences, University of Bristol Genomics Facility, Bristol, United Kingdom
| | - Shelley J. Allen-Birt
- Translational Health Sciences, Learning and Research, Bristol Medical School, Southmead Hospital, Bristol, United Kingdom
| | - Nicola X. West
- Bristol Dental School, Bristol, United Kingdom,*Correspondence: Nicola X. West,
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26
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Hogestyn JM, Salois G, Xie L, Apa C, Youngyunpipatkul J, Pröschel C, Mayer-Pröschel M. Expression of the human herpesvirus 6A latency-associated transcript U94A impairs cytoskeletal functions in human neural cells. Mol Cell Neurosci 2022; 123:103770. [PMID: 36055520 PMCID: PMC10124163 DOI: 10.1016/j.mcn.2022.103770] [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: 05/04/2022] [Revised: 08/12/2022] [Accepted: 08/20/2022] [Indexed: 12/30/2022] Open
Abstract
Many neurodegenerative diseases have a multifactorial etiology and variable course of progression that cannot be explained by current models. Neurotropic viruses have long been suggested to play a role in these diseases, although their exact contributions remain unclear. Human herpesvirus 6A (HHV-6A) is one of the most common viruses detected in the adult brain, and has been clinically associated with multiple sclerosis (MS), and, more recently, Alzheimer's disease (AD). HHV-6A is a ubiquitous viral pathogen capable of infecting glia and neurons. Primary infection in childhood is followed by the induction of latency, characterized by expression of the U94A viral transcript in the absence of viral replication. Here we examine the effects of U94A on cells of the central nervous system. We found that U94A expression inhibits the migration and impairs cytoplasmic maturation of human oligodendrocyte precursor cells (OPCs) without affecting their viability, a phenotype that may contribute to the failure of remyelination seen in many patients with MS. A subsequent proteomics analysis of U94A expression OPCs revealed altered expression of genes involved in tubulin associated cytoskeletal regulation. As HHV-6A seems to significantly be associated with early AD pathology, we extended our initially analysis of the impact of U94A on human derived neurons. We found that U94A expression inhibits neurite outgrowth of primary human cortical neurons and impairs synapse maturation. Based on these data we suggest that U94A expression by latent HHV-6A in glial cells and neurons renders them susceptible to dysfunction and degeneration. Therefore, latent viral infections of the brain represent a unique pathological risk factor that may contribute to disease processes.
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Affiliation(s)
- Jessica M Hogestyn
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA; Department of Neuroscience, School of Medicine and Dentistry, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA
| | - Garrick Salois
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA; Department of Neuroscience, School of Medicine and Dentistry, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA
| | - Li Xie
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA
| | - Connor Apa
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA; Stem cell and Regenerative Medicine Institute, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA
| | - Justin Youngyunpipatkul
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA
| | - Christoph Pröschel
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA; Stem cell and Regenerative Medicine Institute, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA
| | - Margot Mayer-Pröschel
- Department of Biomedical Genetics, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA; Department of Neuroscience, School of Medicine and Dentistry, 601 Elmwood Avenue, Box 633, University of Rochester, Rochester, NY 14642, USA,.
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27
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Vojtechova I, Machacek T, Kristofikova Z, Stuchlik A, Petrasek T. Infectious origin of Alzheimer’s disease: Amyloid beta as a component of brain antimicrobial immunity. PLoS Pathog 2022; 18:e1010929. [PMCID: PMC9671327 DOI: 10.1371/journal.ppat.1010929] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The amyloid cascade hypothesis, focusing on pathological proteins aggregation, has so far failed to uncover the root cause of Alzheimer’s disease (AD), or to provide an effective therapy. This traditional paradigm essentially explains a mechanism involved in the development of sporadic AD rather than its cause. The failure of an overwhelming majority of clinical studies (99.6%) demonstrates that a breakthrough in therapy would be difficult if not impossible without understanding the etiology of AD. It becomes more and more apparent that the AD pathology might originate from brain infection. In this review, we discuss a potential role of bacteria, viruses, fungi, and eukaryotic parasites as triggers of AD pathology. We show evidence from the current literature that amyloid beta, traditionally viewed as pathological, actually acts as an antimicrobial peptide, protecting the brain against pathogens. However, in case of a prolonged or excessive activation of a senescent immune system, amyloid beta accumulation and aggregation becomes damaging and supports runaway neurodegenerative processes in AD. This is paralleled by the recent study by Alam and colleagues (2022) who showed that alpha-synuclein, the protein accumulating in synucleinopathies, also plays a critical physiological role in immune reactions and inflammation, showing an unforeseen link between the 2 unrelated classes of neurodegenerative disorders. The multiplication of the amyloid precursor protein gene, recently described by Lee and collegues (2018), and possible reactivation of human endogenous retroviruses by pathogens fits well into the same picture. We discuss these new findings from the viewpoint of the infection hypothesis of AD and offer suggestions for future research. More than a century after its discovery, Alzheimer’s disease (AD) remains incurable and mysterious. The dominant hypothesis of amyloid cascade has succeeded in explaining the key pathological mechanism, but not its trigger. Amyloid beta has been traditionally considered a pathological peptide, and its physiological functions remain poorly known. These knowledge gaps have contributed to repeated failures of clinical studies. The emerging infectious hypothesis of AD considers central nervous system (CNS) infection the primary trigger of sporadic AD. A closely connected hypothesis claims that amyloid beta is an antimicrobial peptide. In this review, we discuss the available evidence for the involvement of infections in AD, coming from epidemiological studies, post mortem analyses of brain tissue, and experiments in vitro and in vivo. We argue there is no unique “Alzheimer’s germ,” instead, AD is a general reaction of the CNS to chronic infections, in the milieu of an aged immune system. The pathology may become self-sustained even without continuous presence of microbes in the brain. Importantly, the infectious hypothesis leads to testable predictions. Targeting amyloid beta should be ineffective, unless the triggering pathogen and inflammatory response are addressed as well. Meticulous control of selected infections might be the best near-term strategy for AD prevention.
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Affiliation(s)
- Iveta Vojtechova
- National Institute of Mental Health, Klecany, Czech Republic
- Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- * E-mail: , (IV); , (TP)
| | - Tomas Machacek
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | | | - Ales Stuchlik
- National Institute of Mental Health, Klecany, Czech Republic
- Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Tomas Petrasek
- National Institute of Mental Health, Klecany, Czech Republic
- Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- * E-mail: , (IV); , (TP)
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28
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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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29
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Nemergut M, Batkova T, Vigasova D, Bartos M, Hlozankova M, Schenkmayerova A, Liskova B, Sheardova K, Vyhnalek M, Hort J, Laczó J, Kovacova I, Sitina M, Matej R, Jancalek R, Marek M, Damborsky J. Increased occurrence of Treponema spp. and double-species infections in patients with Alzheimer's disease. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:157114. [PMID: 35787909 DOI: 10.1016/j.scitotenv.2022.157114] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/25/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
Although the link between microbial infections and Alzheimer's disease (AD) has been demonstrated in multiple studies, the involvement of pathogens in the development of AD remains unclear. Here, we investigated the frequency of the 10 most commonly cited viral (HSV-1, EBV, HHV-6, HHV-7, and CMV) and bacterial (Chlamydia pneumoniae, Helicobacter pylori, Borrelia burgdorferi, Porphyromonas gingivalis, and Treponema spp.) pathogens in serum, cerebrospinal fluid (CSF) and brain tissues of AD patients. We have used an in-house multiplex PCR kit for simultaneous detection of five bacterial and five viral pathogens in serum and CSF samples from 50 AD patients and 53 healthy controls (CTRL). We observed a significantly higher frequency rate of AD patients who tested positive for Treponema spp. compared to controls (AD: 62.2 %; CTRL: 30.3 %; p-value = 0.007). Furthermore, we confirmed a significantly higher occurrence of cases with two or more simultaneous infections in AD patients compared to controls (AD: 24 %; CTRL 7.5 %; p-value = 0.029). The studied pathogens were detected with comparable frequency in serum and CSF. In contrast, Borrelia burgdorferi, human herpesvirus 7, and human cytomegalovirus were not detected in any of the studied samples. This study provides further evidence of the association between microbial infections and AD and shows that paralleled analysis of multiple sample specimens provides complementary information and is advisable for future studies.
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Affiliation(s)
- Michal Nemergut
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Masaryk University, Brno, Czech Republic
| | - Tereza Batkova
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Department of Neurology, Masaryk University, St. Anne's University Hospital Brno, Brno, Czech Republic; BioVendor R&D, Brno, Czech Republic
| | - Dana Vigasova
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Masaryk University, Brno, Czech Republic
| | | | | | - Andrea Schenkmayerova
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Masaryk University, Brno, Czech Republic
| | - Barbora Liskova
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Masaryk University, Brno, Czech Republic
| | - Katerina Sheardova
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Department of Neurology, Masaryk University, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Martin Vyhnalek
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Department of Neurology, Charles University, Second Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - Jakub Hort
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Department of Neurology, Charles University, Second Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - Jan Laczó
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Department of Neurology, Charles University, Second Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - Ingrid Kovacova
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Michal Sitina
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Radoslav Matej
- Department of Pathology and Molecular Medicine, Third Faculty of Medicine, Charles University and Thomayer University Hospital, Prague, Czech Republic
| | - Radim Jancalek
- Department of Neurosurgery, St. Anne's University Hospital Brno, Brno, Czech Republic and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Martin Marek
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Masaryk University, Brno, Czech Republic
| | - Jiri Damborsky
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic; Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Masaryk University, Brno, Czech Republic.
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30
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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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31
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Tiwari D, Murmu S, Indari O, Jha HC, Kumar S. Targeting Epstein-Barr virus dUTPase, an immunomodulatory protein using anti-viral, anti-inflammatory and neuroprotective phytochemicals. Chem Biodivers 2022; 19:e202200527. [PMID: 35979671 DOI: 10.1002/cbdv.202200527] [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: 05/31/2022] [Accepted: 08/18/2022] [Indexed: 11/05/2022]
Abstract
Although primary infection of Epstein-Barr virus is generally non-lethal, viral reactivation is often associated with fatal outcomes. Regardless, there is no FDA-approved treatment available for this viral infection. The current investigation targets viral maintenance and reactivation by inhibiting the functioning of viral deoxyuridine-triphosphatase (dUTPase) using phytochemicals. The EBV-dUTPase is essential for the maintenance of nucleotide balance and thus, plays a vital role in the viral replication cycle. Additionally, the protein has shown neuroinflammatory effects on the host. To selectively target the protein and possibly alter its activity, we utilized a virtual screening approach and screened 45 phytochemicals reported to have antiviral, anti-inflammatory, and neuroprotective properties. The analysis revealed several phytochemicals bound to the target protein with high affinity. In-silico ADMET and Lipinski's rule analysis predicted favorable druggability of Dehydroevodiamine (DHE) among all the phytochemicals. Further, we corroborated our findings by molecular dynamic simulation and binding affinity estimation. Our outcomes ascertained a stable binding of DHE to EBV-dUTPase primarily through electrostatic interactions. We identified that the protein-ligand binding involves the region around His71, previously reported as a potent drug target site. Conclusively, the phytochemical DHE showed a promising future as a drug development candidate against EBV-dUTPase.
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Affiliation(s)
- Deeksha Tiwari
- IIT Indore: Indian Institute of Technology Indore, BSBE, Lab No 602, Bioengineering group, IIT Indore, Indore, INDIA
| | - Sneha Murmu
- IARI: Indian Agricultural Research Institute, Division of Agricultural Bioinformatics, Pusa, Delhi, INDIA
| | - Omkar Indari
- IIT Indore: Indian Institute of Technology Indore, BSBE, Infection Bioengineering group, Lab no 602, Indore, INDIA
| | - Hem Chandra Jha
- Indian Institute of Technology Indore, Biosciences and Biomedical Engineering, IIT Indore, BSBE, 453552, Indore, INDIA
| | - Sunil Kumar
- IARI: Indian Agricultural Research Institute, Indian Agricultural Statistics Research Institute, Pusa, Delhi, INDIA
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Song L, Chen J, Lo CYZ, Guo Q, Feng J, Zhao XM. Impaired type I interferon signaling activity implicated in the peripheral blood transcriptome of preclinical Alzheimer's disease. EBioMedicine 2022; 82:104175. [PMID: 35863293 PMCID: PMC9304603 DOI: 10.1016/j.ebiom.2022.104175] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 07/04/2022] [Accepted: 07/04/2022] [Indexed: 11/16/2022] Open
Abstract
Background Subjective or objective subtle cognitive decline (SCD) is considered the preclinical manifestation of Alzheimer's disease (AD), which is a potentially crucial window for preventing or delaying the progression of the disease. Methods To explore the potential mechanism of disease progression and identify relevant biomarkers, we comprehensively assessed the peripheral blood transcriptomic alterations in SCD, covering lncRNA, mRNA, and miRNA. Findings Dysregulated protein-coding mRNA at both gene and isoform levels implicated impairment in the type I interferon signaling pathway in SCD. Specifically, this pathway was regulated by the transcription factor STAT1 and ncRNAs NRIR and has-miR-146a-5p. The miRNA-mRNA-lncRNA co-expression network revealed hub genes for the interferon module. Individuals with lower interferon signaling activity and lower expression of a hub gene STAT1 exhibited a higher conversion rate to mild cognitive impairment (MCI). Interpretation Our findings illustrated the down-regulation of interferon signaling activity would potentially increase the risk of disease progression and thus serve as a pre-disease biomarker. Funding This work was partly supported by National Key R&D Program of China (2020YFA0712403), National Natural Science Foundation of China (61932008), Shanghai Municipal Science and Technology Major Project (2018SHZDZX01), the 111 Project (No. B18015) of China, Greater Bay Area Institute of Precision Medicine (Guangzhou) (Grand No. IPM21C008), Natural Science Foundation of Shanghai (21ZR1403200), and Shanghai Center for Brain Science and Brain-Inspired Technology.
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New Insights into the Molecular Interplay between Human Herpesviruses and Alzheimer’s Disease—A Narrative Review. Brain Sci 2022; 12:brainsci12081010. [PMID: 36009073 PMCID: PMC9406069 DOI: 10.3390/brainsci12081010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/24/2022] [Accepted: 07/28/2022] [Indexed: 12/15/2022] Open
Abstract
Human herpesviruses (HHVs) have been implicated as possible risk factors in Alzheimer’s disease (AD) pathogenesis. Persistent lifelong HHVs infections may directly or indirectly contribute to the generation of AD hallmarks: amyloid beta (Aβ) plaques, neurofibrillary tangles composed of hyperphosphorylated tau proteins, and synaptic loss. The present review focuses on summarizing current knowledge on the molecular mechanistic links between HHVs and AD that include processes involved in Aβ accumulation, tau protein hyperphosphorylation, autophagy, oxidative stress, and neuroinflammation. A PubMed search was performed to collect all the available research data regarding the above mentioned mechanistic links between HHVs and AD pathology. The vast majority of research articles referred to the different pathways exploited by Herpes Simplex Virus 1 that could lead to AD pathology, while a few studies highlighted the emerging role of HHV 6, cytomegalovirus, and Epstein–Barr Virus. The elucidation of such potential links may guide the development of novel diagnostics and therapeutics to counter this devastating neurological disorder that until now remains incurable.
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Patrycy M, Chodkowski M, Krzyzowska M. Role of Microglia in Herpesvirus-Related Neuroinflammation and Neurodegeneration. Pathogens 2022; 11:pathogens11070809. [PMID: 35890053 PMCID: PMC9324537 DOI: 10.3390/pathogens11070809] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/15/2022] [Accepted: 07/17/2022] [Indexed: 02/04/2023] Open
Abstract
Neuroinflammation is defined as an inflammatory state within the central nervous system (CNS). Microglia conprise the resident tissue macrophages of the neuronal tissue. Upon viral infection of the CNS, microglia become activated and start to produce inflammatory mediators important for clearance of the virus, but an excessive neuroinflammation can harm nearby neuronal cells. Herpesviruses express several molecular mechanisms, which can modulate apoptosis of infected neurons, astrocytes and microglia but also divert immune response initiated by the infected cells. In this review we also describe the link between virus-related neuroinflammation, and development of neurodegenerative diseases.
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35
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Onisiforou A, Spyrou GM. Immunomodulatory effects of microbiota-derived metabolites at the crossroad of neurodegenerative diseases and viral infection: network-based bioinformatics insights. Front Immunol 2022; 13:843128. [PMID: 35928817 PMCID: PMC9344014 DOI: 10.3389/fimmu.2022.843128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 06/28/2022] [Indexed: 11/13/2022] Open
Abstract
Bidirectional cross-talk between commensal microbiota and the immune system is essential for the regulation of immune responses and the formation of immunological memory. Perturbations of microbiome-immune system interactions can lead to dysregulated immune responses against invading pathogens and/or to the loss of self-tolerance, leading to systemic inflammation and genesis of several immune-mediated pathologies, including neurodegeneration. In this paper, we first investigated the contribution of the immunomodulatory effects of microbiota (bacteria and fungi) in shaping immune responses and influencing the formation of immunological memory cells using a network-based bioinformatics approach. In addition, we investigated the possible role of microbiota-host-immune system interactions and of microbiota-virus interactions in a group of neurodegenerative diseases (NDs): Amyotrophic Lateral Sclerosis (ALS), Multiple Sclerosis (MS), Parkinson’s disease (PD) and Alzheimer’s disease (AD). Our analysis highlighted various aspects of the innate and adaptive immune response systems that can be modulated by microbiota, including the activation and maturation of microglia which are implicated in the development of NDs. It also led to the identification of specific microbiota components which might be able to influence immune system processes (ISPs) involved in the pathogenesis of NDs. In addition, it indicated that the impact of microbiota-derived metabolites in influencing disease-associated ISPs, is higher in MS disease, than in AD, PD and ALS suggesting a more important role of microbiota mediated-immune effects in MS.
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36
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Murdock KW, Stowe RP, Engeland CG. Diminished Cellular Immunity and Executive Cognitive Functioning Among Middle-Aged and Elderly Adults. Psychosom Med 2022; 84:679-684. [PMID: 35420592 DOI: 10.1097/psy.0000000000001080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Within the field of psychoneuroimmunology, much attention has been given to immune dysregulation and its impact on cognitive functioning. Some of this work has focused on the association between high levels of basal proinflammatory cytokines and poorer performance on measures of executive functioning; however, effect sizes have been quite small in human studies. METHODS We investigated whether Epstein-Barr virus (EBV) antibody titers, a marker of immune dysregulation related to cellular immunity, may be associated with executive functioning while also attempting to replicate prior studies using two markers of proinflammatory cytokine production (i.e., circulating and lipopolysaccharide [LPS]-stimulated cytokines [interleukin 6, interleukin 1β, interferon-γ]). A total of 71 community-dwelling adults (mean [standard deviation] age = 60.87 [6.26] years) who were seropositive for EBV infection participated in the study. RESULTS Findings indicated that greater EBV antibody titers were associated with poorer performance on measures of the executive functions of inhibition ( B = -2.36, standard error = 1.06, p = .028) and cognitive flexibility ( B = -2.89, standard error = 1.13, p = .013) when including circulating and LPS-stimulated cytokines and other relevant covariates (i.e., age, sex, and body mass index) in linear regression analyses. Neither circulating nor LPS-stimulated cytokines were associated with performance on the cognitive tasks in the regression analyses. CONCLUSIONS These results suggest that EBV antibody titers may be an indicator of immune dysregulation that is more relevant to executive functioning performance than either circulating or stimulated proinflammatory cytokines among community-dwelling adults.
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Affiliation(s)
- Kyle W Murdock
- From the Department of Biobehavioral Health (Murdock, Engeland), The Pennsylvania State University, University Park, Pennsylvania; Microgen Laboratories (Stowe), La Marque, Texas; and College of Nursing, The Pennsylvania State University (Engeland), University Park, Pennsylvania
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37
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Tiwari D, Mittal N, Jha HC. Unraveling the links between neurodegeneration and Epstein-Barr virus-mediated cell cycle dysregulation. CURRENT RESEARCH IN NEUROBIOLOGY 2022; 3:100046. [PMID: 36685766 PMCID: PMC9846474 DOI: 10.1016/j.crneur.2022.100046] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/22/2022] [Accepted: 06/22/2022] [Indexed: 01/25/2023] Open
Abstract
The Epstein-Barr virus is a well-known cell cycle modulator. To establish successful infection in the host, EBV alters the cell cycle at multiple steps via antigens such as EBNAs, LMPs, and certain other EBV-encoded transcripts. Interestingly, several recent studies have indicated the possibility of EBV's neurotrophic potential. However, the effects and outcomes of EBV infection in the CNS are under-explored. Additionally, more and more epidemiological evidence implicates the cell-cycle dysregulation in neurodegeneration. Numerous hypotheses which describe the triggers that force post-mitotic neurons to re-enter the cell cycle are prevalent. Apart from the known genetic and epigenetic factors responsible, several reports have shown the association of microbial infections with neurodegenerative pathology. Although, studies implicating the herpesvirus family members in neurodegeneration exist, the involvement of Epstein-Barr virus (EBV), in particular, is under-evaluated. Interestingly, a few clinical studies have reported patients of AD or PD to be seropositive for EBV. Based on the findings mentioned above, in this review, we propose that EBV infection in neurons could drive it towards neurodegeneration through dysregulation of cell-cycle events and induction of apoptosis.
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Affiliation(s)
- Deeksha Tiwari
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India
| | - Nitish Mittal
- Computational and Systems Biology, Biozentrum, University of Basel, Klingelbergstrasse 50-70, 4056, Basel, Switzerland,Corresponding author.
| | - Hem Chandra Jha
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India,Corresponding author.
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38
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Romanescu C, Schreiner TG, Mukovozov I. The Role of Human Herpesvirus 6 Infection in Alzheimer’s Disease Pathogenicity—A Theoretical Mosaic. J Clin Med 2022; 11:jcm11113061. [PMID: 35683449 PMCID: PMC9181317 DOI: 10.3390/jcm11113061] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 02/07/2023] Open
Abstract
Alzheimer’s disease (AD), a neurodegenerative disorder generally affecting older adults, is the most common form of dementia worldwide. The disease is marked by severe cognitive and psychiatric decline and has dramatic personal and social consequences. Considerable time and resources are dedicated to the pursuit of a better understanding of disease mechanisms; however, the ultimate goal of obtaining a viable treatment option remains elusive. Neurodegenerative disease as an outcome of gene–environment interaction is a notion widely accepted today; a clear understanding of how external factors are involved in disease pathogenesis is missing, however. In the case of AD, significant effort has been invested in the study of viral pathogens and their role in disease mechanisms. The current scoping review focuses on the purported role HHV-6 plays in AD pathogenesis. First, early studies demonstrating evidence of HHV-6 cantonment in either post-mortem AD brain specimens or in peripheral blood samples of living AD patients are reviewed. Next, selected examples of possible mechanisms whereby viral infection can directly or indirectly contribute to AD pathogenesis are presented, such as autophagy dysregulation, the interaction between miR155 and HHV-6, and amyloid-beta as an antimicrobial peptide. Finally, closely related topics such as HHV-6 penetration in the CNS, HHV-6 involvement in neuroinflammation, and a brief discussion on HHV-6 epigenetics are examined.
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Affiliation(s)
- Constantin Romanescu
- Clinical Section IV, “St. Parascheva” Infectious Disease Hospital, 700116 Iași, Romania
- Correspondence: (C.R.); (T.G.S.)
| | - Thomas Gabriel Schreiner
- Faculty of Medicine, University of Medicine and Pharmacy “Gr. T. Popa”, 700115 Iasi, Romania
- Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 050474 Bucharest, Romania
- Department of Electrical Measurements and Materials, Faculty of Electrical Engineering and Information Technology, Gheorghe Asachi Technical University of Iasi, 21–23 Professor Dimitrie Mangeron Blvd.,700050 Iasi, Romania
- Correspondence: (C.R.); (T.G.S.)
| | - Ilya Mukovozov
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
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39
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McManus RM. The Role of Immunity in Alzheimer's Disease. Adv Biol (Weinh) 2022; 6:e2101166. [PMID: 35254006 DOI: 10.1002/adbi.202101166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 02/03/2022] [Indexed: 01/27/2023]
Abstract
With the increase in the aging population, age-related conditions such as dementia and Alzheimer's disease will become ever more prevalent in society. As there is no cure for dementia and extremely limited therapeutic options, researchers are examining the mechanisms that contribute to the progression of cognitive decline in hopes of developing better therapies and even an effective, long-lasting treatment for this devastating condition. This review will provide an updated perspective on the role of immunity in triggering the changes that lead to the development of dementia. It will detail the latest findings on Aβ- and tau-induced microglial activation, including the role of the inflammasome. The contribution of the adaptive immune system, specifically T cells, will be discussed. Finally, whether the innate and adaptive immune system can be modulated to protect against dementia will be examined, along with an assessment of the prospective candidates for these that are currently in clinical trials.
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Affiliation(s)
- Róisín M McManus
- German Center for Neurodegenerative Diseases (DZNE), 53127, Bonn, Germany
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40
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Amyloid and Tau Protein Concentrations in Children with Meningitis and Encephalitis. Viruses 2022; 14:v14040725. [PMID: 35458457 PMCID: PMC9027807 DOI: 10.3390/v14040725] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 11/18/2022] Open
Abstract
Alzheimer’s disease (AD) has emerged as a growing threat to human health. It is a multifactorial disorder, in which abnormal amyloid beta metabolism and neuroinflammation have been demonstrated to play a key role. Intrathecal inflammation can be triggered by infections and precede brain damage for years. We analyzed the influence of infections of the central nervous system on biomarkers that are crucially involved in AD pathology. Analyses of the cerebrospinal fluid (CSF) levels of Aβ1–42, Aβ1–40, Tau, and pTau proteins were performed in 53 children with neuroinfections of viral (n = 26) and bacterial origin (n = 19), and in controls (n = 8). We found no changes in CSF amyloid Aβ1–42 concentrations, regardless of etiology. We showed an increase in tau and phosphorylated tau concentrations in purulent CNS infections of the brain, compared to other etiologies. Moreover, the total concentrations of tau in the CSF correlated with the CSF absolute number of neutrophils. These findings and the Aβ 42/40 concentration quotient discrepancies in CFS between meningitis and encephalitis suggest that infections may affect the metabolism of AD biomarkers.
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41
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Teles F, Collman RG, Mominkhan D, Wang Y. Viruses, periodontitis, and comorbidities. Periodontol 2000 2022; 89:190-206. [PMID: 35244970 DOI: 10.1111/prd.12435] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Seminal studies published in the 1990s and 2000s explored connections between periodontal diseases and systemic conditions, revealing potential contributions of periodontal diseases in the initiation or worsening of systemic conditions. The resulting field of periodontal medicine led to the publication of studies indicating that periodontal diseases can influence the risk of systemic conditions, including adverse pregnancy outcomes, cardiovascular and respiratory diseases, as well as Alzheimer disease and cancers. In general, these studies hypothesized that the periodontal bacterial insult and/or the associated proinflammatory cascade could contribute to the pathogenesis of these systemic diseases. While investigations of the biological basis of the connections between periodontal diseases and systemic conditions generally emphasized the bacteriome, it is also biologically plausible, under an analogous hypothesis, that other types of organisms may have a similar role. Human viruses would be logical "suspects" in this role, given their ubiquity in the oral cavity, association with periodontal diseases, and ability to elicit strong inflammatory response, compromise immune responses, and synergize with bacteria in favor of a more pathogenic microbial consortium. In this review, the current knowledge of the role of viruses in connecting periodontal diseases and systemic conditions is examined. We will also delve into the mechanistic basis for such connections and highlight the importance of those relationships in the management and treatment of patients.
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Affiliation(s)
- Flavia Teles
- Department of Basic and Translational Sciences, School of Dental Medicine, Center for Innovation & Precision Dentistry, School of Dental Medicine & School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ronald G Collman
- Pulmonary, Allergy and Critical Care Division, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Dana Mominkhan
- Department of Endodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yu Wang
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Zhang N, Zuo Y, Jiang L, Peng Y, Huang X, Zuo L. Epstein-Barr Virus and Neurological Diseases. Front Mol Biosci 2022; 8:816098. [PMID: 35083281 PMCID: PMC8784775 DOI: 10.3389/fmolb.2021.816098] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 12/07/2021] [Indexed: 11/13/2022] Open
Abstract
Epstein-Barr virus (EBV), also known as human herpesvirus 4, is a double-stranded DNA virus that is ubiquitous in 90–95% of the population as a gamma herpesvirus. It exists in two main states, latent infection and lytic replication, each encoding viral proteins with different functions. Human B-lymphocytes and epithelial cells are EBV-susceptible host cells. EBV latently infects B cells and nasopharyngeal epithelial cells throughout life in most immunologically active individuals. EBV-infected cells, free viruses, their gene products, and abnormally elevated EBV titers are observed in the cerebrospinal fluid. Studies have shown that EBV can infect neurons directly or indirectly via infected B-lymphocytes, induce neuroinflammation and demyelination, promote the proliferation, degeneration, and necrosis of glial cells, promote proliferative disorders of B- and T-lymphocytes, and contribute to the occurrence and development of nervous system diseases, such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, acute cerebellar ataxia, meningitis, acute disseminated encephalomyelitis, and brain tumors. However, the specific underlying molecular mechanisms are unclear. In this paper, we review the mechanisms underlying the role of EBV in the development of central nervous system diseases, which could bebeneficial in providing new research ideas and potential clinical therapeutic targets for neurological diseases.
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Affiliation(s)
- Nan Zhang
- Department of Physiology, Institute of Neuroscience Research, Hengyang Key Laboratory of Neurodegeneration and Cognitive Impairment, Hengyang Medical College, University of South China, Hengyang, China
- Hunan Dongkou People’s Hospital, Shaoyang, China
| | - Yuxin Zuo
- Department of Physiology, Institute of Neuroscience Research, Hengyang Key Laboratory of Neurodegeneration and Cognitive Impairment, Hengyang Medical College, University of South China, Hengyang, China
| | - Liping Jiang
- Department of Physiology, Institute of Neuroscience Research, Hengyang Key Laboratory of Neurodegeneration and Cognitive Impairment, Hengyang Medical College, University of South China, Hengyang, China
| | - Yu Peng
- Department of Physiology, Institute of Neuroscience Research, Hengyang Key Laboratory of Neurodegeneration and Cognitive Impairment, Hengyang Medical College, University of South China, Hengyang, China
| | - Xu Huang
- Department of Physiology, Institute of Neuroscience Research, Hengyang Key Laboratory of Neurodegeneration and Cognitive Impairment, Hengyang Medical College, University of South China, Hengyang, China
| | - Lielian Zuo
- Department of Physiology, Institute of Neuroscience Research, Hengyang Key Laboratory of Neurodegeneration and Cognitive Impairment, Hengyang Medical College, University of South China, Hengyang, China
- *Correspondence: Lielian Zuo,
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Sun X, Zhang H, Yao D, Xu Y, Jing Q, Cao S, Tian L, Li C. Integrated Bioinformatics Analysis Identifies Hub Genes Associated with Viral Infection and Alzheimer's Disease. J Alzheimers Dis 2021; 85:1053-1061. [PMID: 34924389 DOI: 10.3233/jad-215232] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Alzheimer's disease (AD) is a fatal neurodegenerative disease, the etiology of which is unclear. Previous studies have suggested that some viruses are neurotropic and associated with AD. OBJECTIVE By using bioinformatics analysis, we investigated the potential association between viral infection and AD. METHODS A total of 5,066 differentially expressed genes (DEGs) in the temporal cortex between AD and control samples were identified. These DEGs were then examined via weighted gene co-expression network analysis (WGCNA) and clustered into modules of genes with similar expression patterns. Of identified modules, module turquoise had the highest correlation with AD. The module turquoise was further characterized using Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enrichment analysis. RESULTS Our results showed that the KEGG pathways of the module turquoise were mainly associated with viral infection signaling, specifically Herpes simplex virus, Human papillomavirus, and Epstein-Barr virus infections. A total of 126 genes were enriched in viral infection signaling pathways. In addition, based on values of module membership and gene significance, a total of 508 genes within the module were selected for further analysis. By intersecting these 508 genes with those 126 genes enriched in viral infection pathways, we identified 4 hub genes that were associated with both viral infection and AD: TLR2, COL1A2, NOTCH3, and ZNF132. CONCLUSION Through bioinformatics analysis, we demonstrated a potential link between viral infection and AD. These findings may provide a platform to further our understanding of AD pathogenesis.
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Affiliation(s)
- Xiaoru Sun
- Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China.,Clinical Research Center for Anesthesiology and Perioperative Medicine, Tongji University, Shanghai, China
| | - Hui Zhang
- Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, P.R. China
| | - Dongdong Yao
- Department of Anesthesiology, Perioperative, and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Anesthesiology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Yaru Xu
- Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, P.R. China
| | - Qi Jing
- Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, P.R. China
| | - Silu Cao
- Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, P.R. China
| | - Li Tian
- Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China.,Clinical Research Center for Anesthesiology and Perioperative Medicine, Tongji University, Shanghai, China
| | - Cheng Li
- Translational Research Institute of Brain and Brain-Like Intelligence, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China.,Clinical Research Center for Anesthesiology and Perioperative Medicine, Tongji University, Shanghai, China
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Wang Y, Luo W, Wang X, Ma Y, Huang L, Wang Y. MAMDC2, a gene highly expressed in microglia in experimental models of Alzheimers Disease, positively regulates the innate antiviral response during neurotropic virus infection. J Infect 2021; 84:187-204. [PMID: 34902449 DOI: 10.1016/j.jinf.2021.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/24/2021] [Accepted: 12/07/2021] [Indexed: 11/20/2022]
Abstract
Microglia, as central nervous system (CNS)-resident macrophages, are the first line of defense against neurotropic virus infection, the immune response of which is implicated in numerous CNS diseases, including Alzheimer's disease (AD). Indeed, the infectious hypothesis for AD has long been recognized, of note herpes simplex virus type 1 (HSV-1), the most common human neurotropic virus. However, the mechanism linking HSV-1 and AD remains obscure. In this study, we analyzed the transcriptome data of microglia in AD mice. We found that MAM domain containing 2 (MAMDC2) is significantly upregulated in microglia isolated from both a series of AD mice established by numerous genetic strategies and mice with HSV-1 infection. Mamdc2-deficient (Mamdc2-/-) mice are susceptible to HSV-1 infection and show an impaired type I interferon (I-IFN)-based innate antiviral response upon neurotropic HSV-1 infection. The in vitro experiments suggest a similar result. Moreover, lentivirus-mediated overexpression of Mamdc2 in mouse brains enhances the innate antiviral response in microglia and ameliorates herpes simplex encephalitis (HSE) symptoms. Mechanistically, MAMDC2 interacts with STING via its first MAM domain within and enhances the polymerization of STING, activating downstream TBK1-IRF3 signaling to facilitate the expression of I-IFNs. The sulfated glycosaminoglycan-mediated polymerization of STING also largely depends on MAMDC2. Our study uncovers the function of MAMDC2 in the innate antiviral response in microglia, revealing a potential mechanism linking HSV-1 and AD, especially the contribution of Mamdc2 overexpression to the upregulation of I-IFN in the AD brain.
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Affiliation(s)
- Yiliang Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, China; State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China; Key Laboratory of Virology of Guangdong Province, Jinan University, Guangzhou, China; Guangdong Province Key Laboratory of Bioengineering Medicine, Jinan University, Guangzhou, China; Guangdong Provincial Biotechnology Drug & Engineering Technology Research Center, Jinan University, Guangzhou, China.
| | - Weisheng Luo
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, China; Key Laboratory of Virology of Guangdong Province, Jinan University, Guangzhou, China; Guangdong Province Key Laboratory of Bioengineering Medicine, Jinan University, Guangzhou, China; Guangdong Provincial Biotechnology Drug & Engineering Technology Research Center, Jinan University, Guangzhou, China
| | - Xiaohui Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, China; Key Laboratory of Virology of Guangdong Province, Jinan University, Guangzhou, China; Guangdong Province Key Laboratory of Bioengineering Medicine, Jinan University, Guangzhou, China; Guangdong Provincial Biotechnology Drug & Engineering Technology Research Center, Jinan University, Guangzhou, China
| | - Yuying Ma
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, China; Guangdong Province Key Laboratory of Bioengineering Medicine, Jinan University, Guangzhou, China; Guangdong Provincial Biotechnology Drug & Engineering Technology Research Center, Jinan University, Guangzhou, China
| | - Lianzhou Huang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, China; Guangdong Province Key Laboratory of Bioengineering Medicine, Jinan University, Guangzhou, China; Guangdong Provincial Biotechnology Drug & Engineering Technology Research Center, Jinan University, Guangzhou, China
| | - Yifei Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Institute of Biomedicine, College of Life Science and Technology, Jinan University, Guangzhou, China; Key Laboratory of Virology of Guangdong Province, Jinan University, Guangzhou, China; Guangdong Province Key Laboratory of Bioengineering Medicine, Jinan University, Guangzhou, China; Guangdong Provincial Biotechnology Drug & Engineering Technology Research Center, Jinan University, Guangzhou, China.
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Human herpesvirus 6A U4 inhibits proteasomal degradation of amyloid precursor protein. J Virol 2021; 96:e0168821. [PMID: 34878807 DOI: 10.1128/jvi.01688-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human herpesvirus 6 (HHV-6) belongs to the betaherpesvirus subfamily and is divided into two distinct species, HHV-6A and HHV-6B. HHV-6 can infect nerve cells and is associated with a variety of nervous system diseases. Recently, the association of HHV-6A infection with Alzheimer's disease (AD) has been suggested. The main pathological phenomena of AD are the accumulation of β-amyloid (Aβ), neurofibrillary tangles, and neuroinflammation, however, the specific molecular mechanism of pathogenesis of AD is not fully clear. In this study, we focused on the effect of HHV-6A U4 gene function on Aβ expression. Co-expression of HHV-6A U4 with APP resulted in inhibition of ubiquitin-mediated proteasomal degradation of amyloid precursor protein (APP). Consequently, accumulation of β-amyloid peptide (Aβ), insoluble neurofibrillary tangles, and loss of neural cells may occur. Immunoprecipitation coupled to mass spectrometry (IP-MS) showed that HHV-6A U4 protein interacts with E3 ubiquitin ligase composed of DDB1 and Cullin 4B which is also responsible for APP degradation. We hypothesize that HHV-6A U4 protein competes with APP for binding to E3 ubiquitin ligase, resulting in inhibition of APP ubiquitin modification and clearance. Finally, this is leading to the increase of APP expression and Aβ deposition, which is the hallmark of AD. These findings provide novel evidence for the etiological hypothesis of AD that can contribute to the further analysis of HHV-6A role in AD. IMPORTANCE The association of HHV-6A infection with Alzheimer's disease has attracted increasing attention, although its role and molecular mechanism remain to be established. Our results here indicate that HHV-6A U4 inhibits APP (amyloid precursor protein) degradation. U4 protein interacts with CRLs (Cullin-RING E3 ubiquitin-protein ligases) which is also responsible for APP degradation. We propose a model that U4 competitively binds to CRLs with APP, resulting in APP accumulation and Aβ generation. Our findings provide new insights into the etiological hypothesis of HHV-6A in AD that can help further analyses.
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Onisiforou A, Spyrou GM. Identification of viral-mediated pathogenic mechanisms in neurodegenerative diseases using network-based approaches. Brief Bioinform 2021; 22:bbab141. [PMID: 34237135 PMCID: PMC8574625 DOI: 10.1093/bib/bbab141] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/01/2021] [Accepted: 03/23/2021] [Indexed: 12/18/2022] Open
Abstract
During the course of a viral infection, virus-host protein-protein interactions (PPIs) play a critical role in allowing viruses to replicate and survive within the host. These interspecies molecular interactions can lead to viral-mediated perturbations of the human interactome causing the generation of various complex diseases. Evidences suggest that viral-mediated perturbations are a possible pathogenic etiology in several neurodegenerative diseases (NDs). These diseases are characterized by chronic progressive degeneration of neurons, and current therapeutic approaches provide only mild symptomatic relief; therefore, there is unmet need for the discovery of novel therapeutic interventions. In this paper, we initially review databases and tools that can be utilized to investigate viral-mediated perturbations in complex NDs using network-based analysis by examining the interaction between the ND-related PPI disease networks and the virus-host PPI network. Afterwards, we present our theoretical-driven integrative network-based bioinformatics approach that accounts for pathogen-genes-disease-related PPIs with the aim to identify viral-mediated pathogenic mechanisms focusing in multiple sclerosis (MS) disease. We identified seven high centrality nodes that can act as disease communicator nodes and exert systemic effects in the MS-enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways network. In addition, we identified 12 KEGG pathways, 5 Reactome pathways and 52 Gene Ontology Immune System Processes by which 80 viral proteins from eight viral species might exert viral-mediated pathogenic mechanisms in MS. Finally, our analysis highlighted the Th17 differentiation pathway, a disease communicator node and part of the 12 underlined KEGG pathways, as a key viral-mediated pathogenic mechanism and a possible therapeutic target for MS disease.
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Affiliation(s)
- Anna Onisiforou
- Department of Bioinformatics, Cyprus Institute of Neurology & Genetics, and the Cyprus School of Molecular Medicine, Cyprus
| | - George M Spyrou
- Department of Bioinformatics, Cyprus Institute of Neurology & Genetics, and professor at the Cyprus School of Molecular Medicine, Cyprus
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Cao D, Wu S, Wang X, Li Y, Xu H, Pan Z, Wu Z, Yang L, Tan X, Li D. Kaposi's sarcoma-associated herpesvirus infection promotes proliferation of SH-SY5Y cells by the Notch signaling pathway. Cancer Cell Int 2021; 21:577. [PMID: 34717617 PMCID: PMC8557577 DOI: 10.1186/s12935-021-02269-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 10/16/2021] [Indexed: 11/13/2022] Open
Abstract
Background The cancer caused by Kaposi’s sarcoma-associated herpesvirus (KSHV) infection is one of the major causes of death in AIDS patients. Some patients have neurological symptoms, which appear to be associated with KSHV infection, based on the neurotropic tendency of this virus in recent years. The objectives of this study were to investigate the effects of KSHV infection on neuronal SH-SY5Y cells and to identify differentially expressed genes. Methods KSHV was collected from islk.219 cells. Real-time PCR was used to quantify KSHV copy numbers. KSHV was used to infect SH-SY5Y cells. The KSHV copy number in the supernatants and mRNA levels of latency-associated nuclear antigen (LANA), ORF26, K8.1 A, and replication and transcriptional activator (RTA) were detected by real-time PCR. Proteins were detected by immunohistochemistry. The effect of KSHV infection on cell proliferation was detected by MTT and Ki-67 staining. Cell migration was evaluated by Transwell and wound healing assays. The cell cycle was analyzed by flow cytometry. The expression of CDK4, CDK5, CDK6, cyclin D1, and p27 were measured by western blotting. The levels of cell cycle proteins were re-examined in LANA-overexpressing SH-SY5Y cells. Transcriptome sequencing was used to identify differentially expressed genes in KSHV-infected cells. The levels of Notch signaling pathway proteins were measured by western blotting. RNA interference was used to silence Notch1 and proliferation were analyzed again. Results SH-SY5Y cells were successfully infected with KSHV, and they maintained the ability to produce virions. KSHV-infected SH-SY5Y expressed LANA, ORF26, K8.1 A, and RTA. After KSHV infection, cell proliferation was enhanced, but cell migration was suppressed. KSHV infection accelerated the G0/G1 phase. CDK4, CDK5, CDK6, and cyclin D1 expression was increased, whereas p27 expression was decreased. After LANA overexpression, CDK4, CDK6 and cyclin D1 expression was increased. Transcriptome sequencing showed that 11,258 genes were upregulated and 1,967 genes were downregulated in KSHV-infected SH-SY5Y. The Notch signaling pathway played a role in KSHV infection in SH-SY5Y, and western blots confirmed that Notch1, NICD, RBP-Jĸ and Hes1 expression was increased. After silencing of Notch1, the related proteins and cell proliferation ability were decreased. Conclusions KSHV infected SH-SY5Y cells and promoted the cell proliferation. KSHV infection increased the expression of Notch signaling pathway proteins, which may have been associated with the enhanced cell proliferation. Supplementary Information The online version contains supplementary material available at 10.1186/s12935-021-02269-0.
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Affiliation(s)
- Dongdong Cao
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Shuyuan Wu
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Xiaolu Wang
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Ying Li
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Huiling Xu
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Zemin Pan
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Zhaofu Wu
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China
| | - Lei Yang
- School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Xiaohua Tan
- School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Dongmei Li
- Key Laboratory of Xinjiang Endemic and Ethnic Diseases/NHC Key Laboratory of Prevention and Treatment of Central Asia High Incidence Diseases, School of Medicine, Shihezi University, Beier Road, Shihezi, Xinjiang, China.
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New Look of EBV LMP1 Signaling Landscape. Cancers (Basel) 2021; 13:cancers13215451. [PMID: 34771613 PMCID: PMC8582580 DOI: 10.3390/cancers13215451] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/01/2021] [Accepted: 10/26/2021] [Indexed: 01/18/2023] Open
Abstract
Simple Summary Epstein-Barr Virus (EBV) infection is associated with various lymphomas and carcinomas as well as other diseases in humans. The transmembrane protein LMP1 plays versatile roles in EBV life cycle and pathogenesis, by perturbing, reprograming, and regulating a large range of host cellular mechanisms and functions, which have been increasingly disclosed but not fully understood so far. We summarize recent research progress on LMP1 signaling, including the novel components LIMD1, p62, and LUBAC in LMP1 signalosome and LMP1 novel functions, such as its induction of p62-mediated selective autophagy, regulation of metabolism, induction of extracellular vehicles, and activation of NRF2-mediated antioxidative defense. A comprehensive understanding of LMP1 signal transduction and functions may allow us to leverage these LMP1-regulated cellular mechanisms for clinical purposes. Abstract The Epstein–Barr Virus (EBV) principal oncoprotein Latent Membrane Protein 1 (LMP1) is a member of the Tumor Necrosis Factor Receptor (TNFR) superfamily with constitutive activity. LMP1 shares many features with Pathogen Recognition Receptors (PRRs), including the use of TRAFs, adaptors, and kinase cascades, for signal transduction leading to the activation of NFκB, AP1, and Akt, as well as a subset of IRFs and likely the master antioxidative transcription factor NRF2, which we have gradually added to the list. In recent years, we have discovered the Linear UBiquitin Assembly Complex (LUBAC), the adaptor protein LIMD1, and the ubiquitin sensor and signaling hub p62, as novel components of LMP1 signalosome. Functionally, LMP1 is a pleiotropic factor that reprograms, balances, and perturbs a large spectrum of cellular mechanisms, including the ubiquitin machinery, metabolism, epigenetics, DNA damage response, extracellular vehicles, immune defenses, and telomere elongation, to promote oncogenic transformation, cell proliferation and survival, anchorage-independent cell growth, angiogenesis, and metastasis and invasion, as well as the development of the tumor microenvironment. We have recently shown that LMP1 induces p62-mediated selective autophagy in EBV latency, at least by contributing to the induction of p62 expression, and Reactive Oxygen Species (ROS) production. We have also been collecting evidence supporting the hypothesis that LMP1 activates the Keap1-NRF2 pathway, which serves as the key antioxidative defense mechanism. Last but not least, our preliminary data shows that LMP1 is associated with the deregulation of cGAS-STING DNA sensing pathway in EBV latency. A comprehensive understanding of the LMP1 signaling landscape is essential for identifying potential targets for the development of novel strategies towards targeted therapeutic applications.
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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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Herpesvirus infections and Alzheimer's disease: a Mendelian randomization study. ALZHEIMERS RESEARCH & THERAPY 2021; 13:158. [PMID: 34560893 PMCID: PMC8464096 DOI: 10.1186/s13195-021-00905-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 09/15/2021] [Indexed: 12/14/2022]
Abstract
Background Observational studies have suggested that herpesvirus infection increased the risk of Alzheimer’s disease (AD), but it is unclear whether the association is causal. The aim of the present study is to evaluate the causal relationship between four herpesvirus infections and AD. Methods We performed a two-sample Mendelian randomization analysis to investigate association of four active herpesvirus infections with AD using summary statistics from genome-wide association studies. The four herpesvirus infections (i.e., chickenpox, shingles, cold sores, mononucleosis) are caused by varicella-zoster virus, herpes simplex virus type 1, and Epstein-Barr virus (EBV), respectively. A large summary statistics data from International Genomics of Alzheimer’s Project was used in primary analysis, including 21,982 AD cases and 41,944 controls. Validation was further performed using family history of AD data from UK Biobank (27,696 cases of maternal AD, 14,338 cases of paternal AD and 272,244 controls). Results We found evidence of a significant association between mononucleosis (caused by EBV) and risk of AD after false discovery rates (FDR) correction (odds ratio [OR] = 1.634, 95% confidence interval [CI] = 1.092–2.446, P = 0.017, FDR-corrected P = 0.034). It has been verified in validation analysis that mononucleosis is also associated with family history of AD (OR [95% CI] = 1.392 [1.061, 1.826], P = 0.017). Genetically predicted shingles were associated with AD risk (OR [95% CI] = 0.867 [0.784, 0.958], P = 0.005, FDR-corrected P = 0.020), while genetically predicted chickenpox was suggestively associated with increased family history of AD (OR [95% CI] = 1.147 [1.007, 1.307], P = 0.039). Conclusions Our findings provided evidence supporting a positive relationship between mononucleosis and AD, indicating a causal link between EBV infection and AD. Further elucidations of this association and underlying mechanisms are likely to identify feasible interventions to promote AD prevention. Supplementary Information The online version contains supplementary material available at 10.1186/s13195-021-00905-5.
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