1
|
Taheri M, Bahrami A, Asadi KK, Mohammadi M, Molaei P, Hashemi M, Nouri F. A review on nonviral, nonbacterial infectious agents toxicity involved in neurodegenerative diseases. Neurodegener Dis Manag 2023; 13:351-369. [PMID: 38357803 DOI: 10.2217/nmt-2023-0004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024] Open
Abstract
Neuronal death, decreased activity or dysfunction of neurotransmitters are some of the pathophysiological reasons for neurodegenerative diseases like Alzheimer's, Parkinson's and multiple sclerosis. Also, there is evidence for the role of infections and infectious agents in neurodegenerative diseases and the effect of some metabolites in microorganisms in the pathophysiology of these diseases. In this study, we intend to evaluate the existing studies on the role of infectious agents and their metabolites on the pathophysiology of neurodegenerative diseases. PubMed, Scopus, Google Scholar and Web of Science search engines were searched. Some infectious agents have been observed in neurodegenerative diseases. Also, isolations of some fungi and microalgae have an improving effect on Parkinson's and Alzheimer's.
Collapse
Affiliation(s)
- Mohammad Taheri
- Department of Medical Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Ali Bahrami
- Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Kiana Kimiaei Asadi
- Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mojdeh Mohammadi
- Department of Pharmacology & Toxicology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Pejman Molaei
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mehrdad Hashemi
- Department of Genetics, Faculty of Advanced Science & Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Fatemeh Nouri
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
| |
Collapse
|
2
|
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.
Collapse
|
3
|
Wang Y, Li M, Kazis LE, Xia W. Clinical outcomes of COVID-19 infection among patients with Alzheimer's disease or mild cognitive impairment. Alzheimers Dement 2022; 18:911-923. [PMID: 35377523 PMCID: PMC9073985 DOI: 10.1002/alz.12665] [Citation(s) in RCA: 4] [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: 09/01/2021] [Revised: 02/23/2022] [Accepted: 02/28/2022] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Alzheimer's disease (AD) and COVID-19 share common risk factors including hypertension. Angiotensin converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARB) are frequently prescribed antihypertension medications. METHODS This study analyzed 436,823 veterans tested for SARS-CoV-2 infection. We conducted both classical and propensity score weighted logistic models to compare COVID-19 outcomes between patients with AD or mild cognitive impairment (MCI) to those without cognitive impairment, and examined effect of ACEI/ARB prescription. RESULTS There was a statistically significant association between AD and increased odds of infection and mortality. MCI was not found to be a risk factor for infection. Subjects with MCI exhibited poor clinical outcomes. Prescribing ARBs but not ACEIs was significantly associated with a lower risk of COVID-19 occurrence among AD and MCI patients. DISCUSSION Exploring beneficial effects of existing medications to reduce the impact of COVID-19 on patients with AD or MCI is highly significant. HIGHLIGHTS There is significant association between Alzheimer's disease (AD) and increased risk of COVID-19 infection and odds of mortality. Subjects with mild cognitive impairment (MCI) defined by claims data exhibit poor clinical outcomes, but MCI was not found to be a risk factor for severe acute respiratory syndrome coronavirus 2 infection. Prescribing angiotensin II receptor blockers was significantly associated with a lower risk of COVID-19 occurrence among AD/MCI patients.
Collapse
Affiliation(s)
- Ying Wang
- Geriatric Research Education and Clinical CenterBedford VA Healthcare SystemBedfordMassachusettsUSA
- Department of Mathematical SciencesBentley UniversityWalthamMassachusettsUSA
| | - Mingfei Li
- Department of Mathematical SciencesBentley UniversityWalthamMassachusettsUSA
- Center for Healthcare Organization and Implementation ResearchBedford VA Healthcare SystemBedfordMassachusettsUSA
| | - Lewis E. Kazis
- Center for Healthcare Organization and Implementation ResearchBedford VA Healthcare SystemBedfordMassachusettsUSA
- Department of Health Law, Policy and ManagementBoston University School of Public HealthBostonMassachusettsUSA
- Harvard Medical SchoolBostonMassachusettsUSA
- Spaulding Rehabilitation HospitalCharlestownMassachusettsUSA
| | - Weiming Xia
- Geriatric Research Education and Clinical CenterBedford VA Healthcare SystemBedfordMassachusettsUSA
- Department of Pharmacology and Experimental TherapeuticsBoston University School of MedicineBostonMassachusettsUSA
| |
Collapse
|
4
|
Rosenblum SL, Kosman DJ. Aberrant Cerebral Iron Trafficking Co-morbid With Chronic Inflammation: Molecular Mechanisms and Pharmacologic Intervention. Front Neurol 2022; 13:855751. [PMID: 35370907 PMCID: PMC8964494 DOI: 10.3389/fneur.2022.855751] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 02/14/2022] [Indexed: 12/24/2022] Open
Abstract
The redox properties that make iron an essential nutrient also make iron an efficient pro-oxidant. Given this nascent cytotoxicity, iron homeostasis relies on a combination of iron transporters, chaperones, and redox buffers to manage the non-physiologic aqueous chemistry of this first-row transition metal. Although a mechanistic understanding of the link between brain iron accumulation (BIA) and neurodegenerative diseases is lacking, BIA is co-morbid with the majority of cognitive and motor function disorders. The most prevalent neurodegenerative disorders, including Alzheimer's Disease (AD), Parkinson's Disease (PD), Multiple System Atrophy (MSA), and Multiple Sclerosis (MS), often present with increased deposition of iron into the brain. In addition, ataxias that are linked to mutations in mitochondrial-localized proteins (Friedreich's Ataxia, Spinocerebellar Ataxias) result in mitochondrial iron accumulation and degradation of proton-coupled ATP production leading to neuronal degeneration. A comorbidity common in the elderly is a chronic systemic inflammation mediated by primary cytokines released by macrophages, and acute phase proteins (APPs) released subsequently from the liver. Abluminal inflammation in the brain is found downstream as a result of activation of astrocytes and microglia. Reasonably, the iron that accumulates in the brain comes from the cerebral vasculature via the microvascular capillary endothelial cells whose tight junctions represent the blood-brain barrier. A premise amenable to experimental interrogation is that inflammatory stress alters both the trans- and para-cellular flux of iron at this barrier resulting in a net accumulation of abluminal iron over time. This review will summarize the evidence that lends support to this premise; indicate the mechanisms that merit delineation; and highlight possible therapeutic interventions based on this model.
Collapse
|
5
|
Wang Z, Wu H, Chen Y, Chen H, Wang X, Yuan W. Lactobacillus paracasei S16 Alleviates Lumbar Disc Herniation by Modulating Inflammation Response and Gut Microbiota. Front Nutr 2021; 8:701644. [PMID: 34447774 PMCID: PMC8382687 DOI: 10.3389/fnut.2021.701644] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/02/2021] [Indexed: 12/12/2022] Open
Abstract
Lumbar disc herniation (LDH) is a common cause for low back pain. In this study, we aimed to explore the effects of a specific Lactobacillus paracasei (L. paracasei), L. paracasei S16, on the symptoms of LDH using a mouse model of LDH. The results showed that L. paracasei S16 treatment improved the behavior, increased the cell proliferation, and decreased the apoptosis in LDH mice. Moreover, L. paracasei S16 treatment alleviated the aberrant inflammation response in the LDH mice, which is characterized by the decreased anti-inflammatory cytokines, increased pro-inflammatory cytokines, and decreased percentage of Th1 and Th2 cells and Th17/Treg ratio. 16S rRNA sequencing results showed that the LDH mice treated with L. paracasei S16 have higher relative abundance of Lachnospiraceae and Ruminococcaceae and lower abundance of Lactobacillaceae than mice in the LDH group. Additionally, the serum metabolites involved in the linoleic acid metabolism, alanine. aspartate, and glutamate, glycerophospholipid, and TCA cycle were significantly decreased and the metabolite involved in purine metabolism was significantly increased after the L. paracasei S16 treatment in the LDH mice. These results showed that administration of L. paracasei S16 can improve inflammation response, alter gut microbiota, and modulate serum metabolomics in a mouse model of LDH.
Collapse
Affiliation(s)
- Zhanchao Wang
- Department of Orthopaedics, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Huiqiao Wu
- Department of Orthopaedics, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Yu Chen
- Department of Orthopaedics, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Huajiang Chen
- Department of Orthopaedics, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Xinwei Wang
- Department of Orthopaedics, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Wen Yuan
- Department of Orthopaedics, Changzheng Hospital, Naval Medical University, Shanghai, China
| |
Collapse
|
6
|
Kuwar R, Rolfe A, Di L, Blevins H, Xu Y, Sun X, Bloom GS, Zhang S, Sun D. A Novel Inhibitor Targeting NLRP3 Inflammasome Reduces Neuropathology and Improves Cognitive Function in Alzheimer's Disease Transgenic Mice. J Alzheimers Dis 2021; 82:1769-1783. [PMID: 34219728 DOI: 10.3233/jad-210400] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and the most common type of dementia. A growing body of evidence has implicated neuroinflammation as an essential player in the etiology of AD. Inflammasomes are intracellular multiprotein complexes and essential components of innate immunity in response to pathogen- and danger-associated molecular patterns. Among the known inflammasomes, the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome plays a critical role in the pathogenesis of AD. OBJECTIVE We recently developed a novel class of small molecule inhibitors that selectively target the NLRP3 inflammasome. One of the lead compounds, JC124, has shown therapeutic efficacy in a transgenic animal model of AD. In this study we tested the preventative efficacy of JC124 in another strain of transgenic AD mice. METHODS In this study, 5-month-old female APP/PS1 and matched wild type mice were treated orally with JC124 for 3 months. After completion of treatment, cognitive functions and AD pathologies, as well as protein expression levels of synaptic proteins, were assessed. RESULTS We found that inhibition of NLRP3 inflammasome with JC124 significantly decreased multiple AD pathologies in APP/PS1 mice, including amyloid-β (Aβ) load, neuroinflammation, and neuronal cell cycle re-entry, accompanied by preserved synaptic plasticity with higher expression of pre- and post-synaptic proteins, increased hippocampal neurogenesis, and improved cognitive functions. CONCLUSION Our study demonstrates the importance of the NLRP3 inflammasome in AD pathological development, and pharmacological inhibition of NLRP3 inflammasome with small molecule inhibitors represents a potential therapy for AD.
Collapse
Affiliation(s)
- Ram Kuwar
- Department of Anatomy and Neurobiology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Andrew Rolfe
- Department of Anatomy and Neurobiology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Long Di
- Department of Anatomy and Neurobiology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Hallie Blevins
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, USA
| | - Yiming Xu
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, USA
| | - Xuehan Sun
- Departments of Biology, University of Virginia, Charlottesville, VA, USA
| | - George S Bloom
- Departments of Biology, University of Virginia, Charlottesville, VA, USA.,Departments of Cell Biology, University of Virginia, Charlottesville, VA, USA.,Departments of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Shijun Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, USA
| | - Dong Sun
- Department of Anatomy and Neurobiology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| |
Collapse
|
7
|
Nayeri T, Sarvi S, Sharif M, Daryani A. Toxoplasma gondii: A possible etiologic agent for Alzheimer's disease. Heliyon 2021; 7:e07151. [PMID: 34141920 PMCID: PMC8187970 DOI: 10.1016/j.heliyon.2021.e07151] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/03/2021] [Accepted: 05/24/2021] [Indexed: 01/03/2023] Open
Abstract
Toxoplasma gondii (T. gondii) is one of the most pervasive neurotropic pathogens causing different lesions in a wide variety of mammals as intermediate hosts, including humans. It is estimated that one-third of the world population is infected with T. gondii; however, for a long time, there has been much interest in the examination of the possible role of this parasite in the development of mental disorders, such as Alzheimer's disease (AD). T. gondii may play a role in the progression of AD using mechanisms, such as the induction of the host's immune responses, inflammation of the central nervous system (CNS), alteration in the levels of neurotransmitters, and activation of indoleamine-2,3-dyoxigenase. This paper presents an appraisal of the literature, reports, and studies that seek to the possible role of T. gondii in the development of AD. For achieving the purpose of the current study, a search of six English databases (PubMed, ScienceDirect, Web of Science, Scopus, ProQuest, and Google Scholar) was performed. The results support the involvement of T. gondii in the induction and development of AD. Indeed, T. gondii can be considered a risk factor for the development of AD and requires the special attention of specialists and patients. Furthermore, the results of this study may contribute to prevent or delay the progress of AD worldwide. Therefore, it is required to carry out further studies in order to better perceive the parasitic mechanisms in the progression of AD.
Collapse
Affiliation(s)
- Tooran Nayeri
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran
- Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
- Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Shahabeddin Sarvi
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran
- Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mehdi Sharif
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran
- Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran
- Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| |
Collapse
|
8
|
Morgan DG, Mielke MM. Knowledge gaps in Alzheimer's disease immune biomarker research. Alzheimers Dement 2021; 17:2030-2042. [PMID: 33984178 DOI: 10.1002/alz.12342] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 03/08/2021] [Accepted: 03/11/2021] [Indexed: 11/09/2022]
Abstract
Considerable evidence has accumulated implicating a role for immune mechanisms in moderating the pathology in Alzheimer's disease dementia. However, the appropriate therapeutic target, the appropriate direction of manipulation, and the stage of disease at which to begin treatment remain unanswered questions. Part of the challenge derives from the absence of any selective pressure to develop a coordinated beneficial immune response to severe neural injury in adults. Thus, immune responses to the prevailing stimuli are likely to contain both beneficial and detrimental components. Knowledge gaps include: (1) how a biomarker change relates to the underlying biology, (2) the degree to which pathological stage group differences reflect a response to pathology versus trait differences among individuals regulating risk of developing pathology, (3) the degree to which biomarker levels are predictive of subsequent changes in pathology and/or cognition, and (4) experimental manipulations in model systems to determine whether differences in immune biomarkers are causally related to pathology.
Collapse
Affiliation(s)
- David G Morgan
- Alzheimer's Alliance, Department of Translational Neuroscience, College of Human Medicine, Michigan State University, Grand Rapids, Michigan, USA
| | - Michelle M Mielke
- Division of Epidemiology, Department of Health Sciences Research, Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
| |
Collapse
|
9
|
Walker AC, Bhargava R, Vaziriyan-Sani AS, Pourciau C, Donahue ET, Dove AS, Gebhardt MJ, Ellward GL, Romeo T, Czyż DM. Colonization of the Caenorhabditis elegans gut with human enteric bacterial pathogens leads to proteostasis disruption that is rescued by butyrate. PLoS Pathog 2021; 17:e1009510. [PMID: 33956916 PMCID: PMC8101752 DOI: 10.1371/journal.ppat.1009510] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 03/29/2021] [Indexed: 12/12/2022] Open
Abstract
Protein conformational diseases are characterized by misfolding and toxic aggregation of metastable proteins, often culminating in neurodegeneration. Enteric bacteria influence the pathogenesis of neurodegenerative diseases; however, the complexity of the human microbiome hinders our understanding of how individual microbes influence these diseases. Disruption of host protein homeostasis, or proteostasis, affects the onset and progression of these diseases. To investigate the effect of bacteria on host proteostasis, we used Caenorhabditis elegans expressing tissue-specific polyglutamine reporters that detect changes in the protein folding environment. We found that colonization of the C. elegans gut with enteric bacterial pathogens disrupted proteostasis in the intestine, muscle, neurons, and the gonad, while the presence of bacteria that conditionally synthesize butyrate, a molecule previously shown to be beneficial in neurodegenerative disease models, suppressed aggregation and the associated proteotoxicity. Co-colonization with this butyrogenic strain suppressed bacteria-induced protein aggregation, emphasizing the importance of microbial interaction and its impact on host proteostasis. Further experiments demonstrated that the beneficial effect of butyrate depended on the bacteria that colonized the gut and that this protective effect required SKN-1/Nrf2 and DAF-16/FOXO transcription factors. We also found that bacteria-derived protein aggregates contribute to the observed disruption of host proteostasis. Together, these results reveal the significance of enteric infection and gut dysbiosis on the pathogenesis of protein conformational diseases and demonstrate the potential of using butyrate-producing microbes as a preventative and treatment strategy for neurodegenerative disease.
Collapse
Affiliation(s)
- Alyssa C. Walker
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Rohan Bhargava
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Alfonso S. Vaziriyan-Sani
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Christine Pourciau
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Emily T. Donahue
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Autumn S. Dove
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Michael J. Gebhardt
- Division of Infectious Diseases, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Garrett L. Ellward
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Tony Romeo
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Daniel M. Czyż
- Department of Microbiology & Cell Science, University of Florida, Gainesville, Florida, United States of America
| |
Collapse
|
10
|
Ekundayo TC, Olasehinde TA, Okaiyeto K, Okoh AI. Microbial Pathogenesis and Pathophysiology of Alzheimer's Disease: A Systematic Assessment of Microorganisms' Implications in the Neurodegenerative Disease. Front Neurosci 2021; 15:648484. [PMID: 33994926 PMCID: PMC8113417 DOI: 10.3389/fnins.2021.648484] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/29/2021] [Indexed: 11/13/2022] Open
Abstract
Microbial infections have been linked to the pathogenesis and pathophysiology of Alzheimer's disease (AD) and other neurodegenerative diseases. The present study aimed to synthesise and assess global evidence of microbial pathogenesis and pathophysiology in AD (MPP-AD) and associated neurodegenerative conditions using integrated science mapping and content analytics to explore the associated research landscape. Relevant MPP-AD documents were retrieved from Web of Science and Scopus according to PRISMA principles and analysed for productivity/trend linked to authors/countries, thematic conceptual framework, and international collaborative networks. A total of 258 documents published from 136 sources to 39.42 average citations/document were obtained on MPP-AD. The co-authors per document were 7.6, and the collaboration index was 5.71. The annual research outputs increased tremendously in the last 6 years from 2014 to 2019, accounting for 66% compared with records in the early years from 1982 to 1990 (16%). The USA (n = 71, freq. = 30.34%), United Kingdom (n = 32, freq. = 13.68%) and China (n = 27, 11.54%) ranked in first three positions in term of country's productivity. Four major international collaboration clusters were found in MPP-AD research. The country collaboration network in MPP-AD was characteristic of sparse interaction and acquaintanceship (density = 0.11, diameter = 4). Overall, international collaboration is globally inadequate [centralisation statistics: degree (40.5%), closeness (4%), betweenness (23%), and eigenvector (76.7%)] against the robust authors' collaboration index of 5.71 in MPP-AD research. Furthermore, four conceptual thematic frameworks (CTF) namely, CTF#1, roles of microbial/microbiome infection and dysbiosis in cognitive dysfunctions; CTF#2, bacterial infection specific roles in dementia; CTF#3, the use of yeast as a model system for studying MPP-AD and remediation therapy; and CFT#4, flow cytometry elucidation of amyloid-beta and aggregation in Saccharomyces cerevisiae model. Finally, aetiology-based mechanisms of MPP-AD, namely, gut microbiota, bacterial infection, and viral infection, were comprehensively discussed. This study provides an overview of MPP-AD and serves as a stepping stone for future preparedness in MPP-AD-related research.
Collapse
Affiliation(s)
- Temitope Cyrus Ekundayo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa.,Department of Biological Sciences, University of Medical Sciences, Ondo, Nigeria
| | - Tosin Abiola Olasehinde
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa.,Nutrition and Toxicology Division, Food Technology Department, Federal Institute of Industrial Research Oshodi, Lagos, Nigeria
| | - Kunle Okaiyeto
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa.,Department of Environmental Health Sciences, College of Medical and Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
| |
Collapse
|
11
|
Andreadou EG, Katsipis G, Tsolaki M, Pantazaki AA. Involvement and relationship of bacterial lipopolysaccharides and cyclooxygenases levels in Alzheimer's Disease and Mild Cognitive Impairment patients. J Neuroimmunol 2021; 357:577561. [PMID: 34091099 DOI: 10.1016/j.jneuroim.2021.577561] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/24/2021] [Accepted: 03/29/2021] [Indexed: 11/30/2022]
Abstract
This study reports elevated levels of bacterial lipopolysaccharides (LPSs) and cyclooxygenases (COX-1/2) in blood serum and cerebrospinal fluid (CSF) of Alzheimer's Disease (AD) and Mild Cognitive Impairment (MCI) patients compared to cognitively healthy individuals, indicating LPSs as promising biomarkers, especially in serum. LPSs, in both fluids, positively correlate with COX-1/2, Αβ42 and tau and negatively with mental state. Furthermore, COX-2 is the main determinant of LPSs presence in serum, whereas COX-1 in CSF. These results underline the significance of microbial/ inflammatory involvement in dementia and offer novel perspectives on the roles of LPSs and COX in pathogenesis of AD.
Collapse
Affiliation(s)
- Eleni G Andreadou
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; Center for Interdisciplinary Research and Innovation, Laboratory of Neurodegenerative Diseases (LND), 57001 Thermi, Thessaloniki, Greece.
| | - Georgios Katsipis
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; Center for Interdisciplinary Research and Innovation, Laboratory of Neurodegenerative Diseases (LND), 57001 Thermi, Thessaloniki, Greece
| | - Magda Tsolaki
- First Neurology Department, "AHEPA" University General Hospital of Thessaloniki, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; Greek Association of Alzheimer's Disease and Related Disorders - GAADRD, Greece; Center for Interdisciplinary Research and Innovation, Laboratory of Neurodegenerative Diseases (LND), 57001 Thermi, Thessaloniki, Greece
| | - Anastasia A Pantazaki
- Laboratory of Biochemistry, Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; Center for Interdisciplinary Research and Innovation, Laboratory of Neurodegenerative Diseases (LND), 57001 Thermi, Thessaloniki, Greece.
| |
Collapse
|
12
|
Zhang LN, Li MJ, Shang YH, Zhao FF, Huang HC, Lao FX. Independent and Correlated Role of Apolipoprotein E ɛ4 Genotype and Herpes Simplex Virus Type 1 in Alzheimer's Disease. J Alzheimers Dis 2020; 77:15-31. [PMID: 32804091 DOI: 10.3233/jad-200607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The ɛ4 allele of the Apolipoprotein E (APOE) gene in individuals infected by Herpes simplex virus type 1 (HSV-1) has been demonstrated to be a risk factor in Alzheimer's disease (AD). APOE-ɛ4 reduces the levels of neuronal cholesterol, interferes with the transportation of cholesterol, impairs repair of synapses, decreases the clearance of neurotoxic peptide amyloid-β (Aβ), and promotes the deposition of amyloid plaque, and eventually may cause development of AD. HSV-1 enters host cells and can infect the olfactory system, trigeminal ganglia, entorhinal cortex, and hippocampus, and may cause AD-like pathological changes. The lifecycle of HSV-1 goes through a long latent phase. HSV-1 induces neurotropic cytokine expression with pro-inflammatory action and inhibits antiviral cytokine production in AD. It should be noted that interferons display antiviral activity in HSV-1-infected AD patients. Reactivated HSV-1 is associated with infectious burden in cognitive decline and AD. Finally, HSV-1 DNA has been confirmed as present in human brains and is associated with APOEɛ4 in AD. HSV-1 and APOEɛ4 increase the risk of AD and relate to abnormal autophagy, higher concentrations of HSV-1 DNA in AD, and formation of Aβ plaques and neurofibrillary tangles.
Collapse
Affiliation(s)
- Li-Na Zhang
- Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, P.R. China.,Institute of Functional Factors and Brain Science, Beijing Union University, Beijing, P.R. China.,College of Biochemical Engineering, Beijing Union University, Beijing, P.R. China
| | - Meng-Jie Li
- Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, P.R. China.,Institute of Functional Factors and Brain Science, Beijing Union University, Beijing, P.R. China.,College of Biochemical Engineering, Beijing Union University, Beijing, P.R. China
| | - Ying-Hui Shang
- Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, P.R. China.,Institute of Functional Factors and Brain Science, Beijing Union University, Beijing, P.R. China.,College of Biochemical Engineering, Beijing Union University, Beijing, P.R. China
| | - Fan-Fan Zhao
- Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, P.R. China.,Institute of Functional Factors and Brain Science, Beijing Union University, Beijing, P.R. China.,College of Biochemical Engineering, Beijing Union University, Beijing, P.R. China
| | - Han-Chang Huang
- Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, P.R. China.,Institute of Functional Factors and Brain Science, Beijing Union University, Beijing, P.R. China.,College of Biochemical Engineering, Beijing Union University, Beijing, P.R. China
| | - Feng-Xue Lao
- Beijing Key Laboratory of Bioactive Substances and Functional Foods, Beijing Union University, Beijing, P.R. China.,Institute of Functional Factors and Brain Science, Beijing Union University, Beijing, P.R. China.,College of Biochemical Engineering, Beijing Union University, Beijing, P.R. China
| |
Collapse
|
13
|
Epstein AL. [Alzheimer's disease, neuro-inflammation, and herpes viruses, a path that traces its way]. Med Sci (Paris) 2020; 36:479-486. [PMID: 32452370 DOI: 10.1051/medsci/2020090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Infection of the brain with various types of pathogens, and the resulting inflammatory response, is becoming increasingly important in our understanding of the etiology of Alzheimer's disease (AD). The fact that several genes identified as risk factors are actually involved in the modulation of the immune response, as well as the very diversity of the infectious agents identified as possible actors in the evolution of this disease, argue in favor of the neuro-inflammatory hypothesis, as does the demonstration that the protein Aβ, one of the most important markers of AD, is an antimicrobial peptide. Among others, herpes viruses (mainly, but not only, HSV-1), which can establish latent infections in brain neurons, especially in the elder population, punctuated by episodes of reactivation following stress or immunosuppression, appear as very strong candidates to play an etiological role, if only as cofactors, of AD. Recent results show that, in human and rat neurons, infection with HSV-1 increases the formation of Aβ along the amyloidogenic pathway, as well as the phosphorylation of Tau proteins, another essential marker of AD. The growing evidence that chronic infections and defense mechanisms, including inflammatory processes, are at the heart of AD, warrants reviewing antiviral drugs such as acyclovir, and possibly vaccination, as potential avenues for AD control.
Collapse
Affiliation(s)
- Alberto L Epstein
- UMR Inserm U1179 - UVSQ - UFR des sciences de la santé Simone Veil, Université de Versailles-Saint-Quentin-en-Yvelines, 2 avenue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| |
Collapse
|
14
|
Zhou H, Chen Z, Limpanont Y, Hu Y, Ma Y, Huang P, Dekumyoy P, Zhou M, Cheng Y, Lv Z. Necroptosis and Caspase-2-Mediated Apoptosis of Astrocytes and Neurons, but Not Microglia, of Rat Hippocampus and Parenchyma Caused by Angiostrongylus cantonensis Infection. Front Microbiol 2020; 10:3126. [PMID: 32038563 PMCID: PMC6989440 DOI: 10.3389/fmicb.2019.03126] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 12/24/2019] [Indexed: 01/18/2023] Open
Abstract
Infection with the roundworm Angiostrongylus cantonensis is the main cause of eosinophilic meningitis worldwide. The underlying molecular basis of the various pathological outcomes in permissive and non-permissive hosts infected with A. cantonensis remains poorly defined. In the present study, the histology of neurological disorders in the central nervous system (CNS) of infected rats was assessed by using hematoxylin and eosin staining. Quantitative reverse transcription polymerase chain reaction (RT-qPCR), western blot and immunofluorescence (IF) were used in evolutions of the transcription and translation levels of the apoptosis-, necroptosis-, autophagy-, and pyroptosis-related genes. The distribution of apoptotic and necroptotic cells in the rat hippocampus and parenchyma was further detected using flow cytometry, and the features of the ultrastructure of the cells were examined by transmission electron microscopy (TEM). The inflammatory response upon CNS infection with A. cantonensis evolved, as characterized by the accumulation of a small number of inflammatory cells under the thickened meninges, which peaked at 21 days post-infection (dpi) and returned to normal by 35 dpi. The transcription levels and translation of caspase-2, caspase-8, RIP1 and RIP3 increased significantly at 21 and 28 dpi but decreased sharply at 35 dpi compared to those in the normal control group. However, the changes in the expression of caspase-1, caspase-3, caspase-11, Beclin-1 and LC3B were not obvious, suggesting that apoptosis and necroptosis but not autophagy or pyroptosis occurred in the brains of infected animals at 21 and 28 dpi. The results of RT-qPCR, western blot analysis, IF, flow cytometry and TEM further illustrated that necroptosis and caspase-2-mediated apoptosis occurred in astrocytes and neurons but not in microglia in the parenchyma and hippocampus of infected animals. This study provides the first evidence that neuronal and astrocytic necroptosis and caspase-2-mediated apoptosis are induced by A. cantonensis infection in the parenchymal and hippocampal regions of rats at 21 and 28 dpi but these processes are negligible at 35 dpi. These findings enhance our understanding of the pathogenesis of A. cantonensis infection and provide new insights into therapeutic approaches targeting the occurrence of cell death in astrocytes and neurons in infected patients.
Collapse
Affiliation(s)
- Hongli Zhou
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Zhe Chen
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Yanin Limpanont
- Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Yue Hu
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Yubin Ma
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Ping Huang
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Paron Dekumyoy
- Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Minyu Zhou
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Yixin Cheng
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
| | - Zhiyue Lv
- Joint Program of Pathobiology, The Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, China
- Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| |
Collapse
|
15
|
Santiago JA, Bottero V, Potashkin JA. Transcriptomic and Network Analysis Highlight the Association of Diabetes at Different Stages of Alzheimer's Disease. Front Neurosci 2019; 13:1273. [PMID: 31849586 PMCID: PMC6895844 DOI: 10.3389/fnins.2019.01273] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/11/2019] [Indexed: 12/14/2022] Open
Abstract
Alzheimer's disease (AD) and type 2 diabetes (T2D) are among the most prevalent chronic diseases affecting the aging population. Extensive research evidence indicates that T2D is a well-established risk factor for AD; however, the molecular mechanisms underlying this association have not been fully elucidated. Furthermore, how T2D may contribute to the progression of AD is a subject of extensive investigation. In this study, we compared the blood transcriptome of patients with mild cognitive impairment (MCI), AD, and advanced AD to those afflicted with T2D to unveil shared and unique pathways and potential therapeutic targets. Blood transcriptomic analyses revealed a positive correlation between gene expression profiles of MCI, AD, and T2D in seven independent microarrays. Interestingly, gene expression profiles from women with advanced AD correlated negatively with T2D, suggesting sex-specific differences in T2D as a risk factor for AD. Network and pathway analysis revealed that shared molecular networks between MCI and T2D were predominantly enriched in inflammation and infectious diseases whereas those networks shared between overt AD and T2D were involved in the phosphatidylinositol 3-kinase and protein kinase B/Akt (PI3K-AKT) signaling pathway, a major mediator of insulin signaling in the body. The PI3K-AKT signaling pathway became more significantly dysregulated in the advanced AD and T2D shared network. Furthermore, endocrine resistance and atherosclerosis pathways emerged as dysregulated pathways in the advanced AD and T2D shared network. Interestingly, network analysis of shared differentially expressed genes between children with T2D and MCI subjects identified forkhead box O3 (FOXO3) as a central transcriptional regulator, suggesting that it may be a potential therapeutic target for early intervention in AD. Collectively, these results suggest that T2D may be implicated at different stages of AD through different molecular pathways disrupted during the preclinical phase of AD and more advanced stages of the disease.
Collapse
Affiliation(s)
| | - Virginie Bottero
- Department of Cellular and Molecular Pharmacology, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Judith A Potashkin
- Department of Cellular and Molecular Pharmacology, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| |
Collapse
|
16
|
Meta-Analysis of Gene Expression Changes in the Blood of Patients with Mild Cognitive Impairment and Alzheimer's Disease Dementia. Int J Mol Sci 2019; 20:ijms20215403. [PMID: 31671574 PMCID: PMC6862214 DOI: 10.3390/ijms20215403] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/25/2019] [Accepted: 10/28/2019] [Indexed: 12/11/2022] Open
Abstract
Background: Dementia is a major public health concern affecting approximately 47 million people worldwide. Mild cognitive impairment (MCI) is one form of dementia that affects an individual’s memory with or without affecting their daily life. Alzheimer’s disease dementia (ADD) is a more severe form of dementia that usually affects elderly individuals. It remains unclear whether MCI is a distinct disorder from or an early stage of ADD. Methods: Gene expression data from blood were analyzed to identify potential biomarkers that may be useful for distinguishing between these two forms of dementia. Results: A meta-analysis revealed 91 genes dysregulated in individuals with MCI and 387 genes dysregulated in ADD. Pathway analysis identified seven pathways shared between MCI and ADD and nine ADD-specific pathways. Fifteen transcription factors were associated with MCI and ADD, whereas seven transcription factors were specific for ADD. Mir-335-5p was specific for ADD, suggesting that it may be useful as a biomarker. Diseases that are associated with MCI and ADD included developmental delays, cognition impairment, and movement disorders. Conclusion: These results provide a better molecular understanding of peripheral changes that occur in MCI and ADD patients and may be useful in the identification of diagnostic and prognostic biomarkers.
Collapse
|
17
|
Lysozyme encapsulated gold nanoclusters for probing the early stage of lysozyme aggregation under acidic conditions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2019; 197:111540. [DOI: 10.1016/j.jphotobiol.2019.111540] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 06/02/2019] [Accepted: 06/21/2019] [Indexed: 12/22/2022]
|
18
|
Anastasio TJ. Exploring the Correlation between the Cognitive Benefits of Drug Combinations in a Clinical Database and the Efficacies of the Same Drug Combinations Predicted from a Computational Model. J Alzheimers Dis 2019; 70:287-302. [PMID: 31177222 PMCID: PMC6700640 DOI: 10.3233/jad-190144] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Identification of drug combinations that could be effective in Alzheimer’s disease treatment is made difficult by the sheer number of possible combinations. This analysis identifies as potentially therapeutic those drug combinations that rank highest when their efficacy is determined jointly from two independent data sources. Estimates of the efficacy of the same drug combinations were derived from a clinical dataset on cognitively impaired elderly participants and from pre-clinical data, in the form of a computational model of neuroinflammation. Linear regression was used to show that the two sets of estimates were correlated, and to rule out confounds. The ten highest ranking, jointly determined drug combinations most frequently consisted of COX2 inhibitors and aspirin, along with various antihypertensive medications. Ten combinations of from five to nine drugs, and the three-drug combination of a COX2 inhibitor, aspirin, and a calcium-channel blocker, are discussed as candidates for consideration in future pre-clinical and clinical studies.
Collapse
Affiliation(s)
- Thomas J Anastasio
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| |
Collapse
|
19
|
Ashraf GM, Tarasov VV, Makhmutovа A, Chubarev VN, Avila-Rodriguez M, Bachurin SO, Aliev G. The Possibility of an Infectious Etiology of Alzheimer Disease. Mol Neurobiol 2018; 56:4479-4491. [DOI: 10.1007/s12035-018-1388-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 09/27/2018] [Indexed: 12/26/2022]
|
20
|
Prasansuklab A, Theerasri A, Payne M, Ung AT, Tencomnao T. Acid-base fractions separated from Streblus asper leaf ethanolic extract exhibited antibacterial, antioxidant, anti-acetylcholinesterase, and neuroprotective activities. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2018; 18:223. [PMID: 30041641 PMCID: PMC6057052 DOI: 10.1186/s12906-018-2288-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/12/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND Streblus asper is a well-known plant native to Southeast Asia. Different parts of the plant have been traditionally used for various medicinal purposes. However, there is very little scientific evidence reporting its therapeutic benefits for potential treatment of Alzheimer's disease (AD). The study aimed to evaluate antibacterial, antioxidant, acetylcholinesterase (AChE) inhibition, and neuroprotective properties of S. asper leaf extracts with the primary objective of enhancing therapeutic applications and facilitating activity-guided isolation of the active chemical constituents. METHODS The leaves of S. asper were extracted in ethanol and subsequently fractionated into neutral, acid and base fractions. The phytochemical constituents of each fraction were analyzed using GC-MS. The antibacterial activity was evaluated using a broth microdilution method. The antioxidant activity was determined using DPPH and ABTS radical scavenging assays. The neuroprotective activity against glutamate-induced toxicity was tested on hippocampal neuronal HT22 cell line by evaluating the cell viability using MTT assay. The AChE inhibitory activity was screened by thin-layer chromatography (TLC) bioautographic method. RESULTS The partition of the S. asper ethanolic leaf extract yielded the highest mass of phytochemical constitutions in the neutral fraction and the lowest in the basic fraction. Amongst the three fractions, the acidic fraction showed the strongest antibacterial activity against gram-positive bacteria. The antioxidant activities of three fractions were found in the order of acidic > basic > neutral, whereas the decreasing order of neuroprotective activity was neutral > basic > acidic. TLC bioautography revealed one component in the neutral fraction exhibited anti-AChE activity. While in the acid fraction, two components showed inhibitory activity against AChE. GC-MS analysis of three fractions showed the presence of major phytochemical constituents including terpenoids, steroids, phenolics, fatty acids, and lipidic plant hormone. CONCLUSIONS Our findings have demonstrated the therapeutic potential of three fractions extracted from S. asper leaves as a promising natural source for neuroprotective agents with additional actions of antibacterials and antioxidants, along with AChE inhibitors that will benefit in the development of new natural compounds in therapies against AD.
Collapse
Affiliation(s)
- Anchalee Prasansuklab
- Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 10330 Thailand
| | - Atsadang Theerasri
- Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 10330 Thailand
| | - Matthew Payne
- School of Mathematical and Physical Sciences, Faculty of Science, The University of Technology Sydney, Sydney, NSW 2007 Australia
| | - Alison T. Ung
- School of Mathematical and Physical Sciences, Faculty of Science, The University of Technology Sydney, Sydney, NSW 2007 Australia
| | - Tewin Tencomnao
- Age-Related Inflammation and Degeneration Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 10330 Thailand
| |
Collapse
|
21
|
Hunter S, Smailagic N, Brayne C. Dementia Research: Populations, Progress, Problems, and Predictions. J Alzheimers Dis 2018; 64:S119-S143. [DOI: 10.3233/jad-179927] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Sally Hunter
- Institute of Public Health, University of Cambridge, Cambridge, UK
| | - Nadja Smailagic
- Institute of Public Health, University of Cambridge, Cambridge, UK
| | - Carol Brayne
- Institute of Public Health, University of Cambridge, Cambridge, UK
| |
Collapse
|
22
|
Pretorius E, Bester J, Kell DB. A Bacterial Component to Alzheimer's-Type Dementia Seen via a Systems Biology Approach that Links Iron Dysregulation and Inflammagen Shedding to Disease. J Alzheimers Dis 2018; 53:1237-56. [PMID: 27340854 PMCID: PMC5325058 DOI: 10.3233/jad-160318] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The progression of Alzheimer's disease (AD) is accompanied by a great many observable changes, both molecular and physiological. These include oxidative stress, neuroinflammation, and (more proximal to cognitive decline) the death of neuronal and other cells. A systems biology approach seeks to organize these observed variables into pathways that discriminate those that are highly involved (i.e., causative) from those that are more usefully recognized as bystander effects. We review the evidence that iron dysregulation is one of the central causative pathway elements here, as this can cause each of the above effects. In addition, we review the evidence that dormant, non-growing bacteria are a crucial feature of AD, that their growth in vivo is normally limited by a lack of free iron, and that it is this iron dysregulation that is an important factor in their resuscitation. Indeed, bacterial cells can be observed by ultrastructural microscopy in the blood of AD patients. A consequence of this is that the growing cells can shed highly inflammatory components such as lipopolysaccharides (LPS). These too are known to be able to induce (apoptotic and pyroptotic) neuronal cell death. There is also evidence that these systems interact with elements of vitamin D metabolism. This integrative systems approach has strong predictive power, indicating (as has indeed been shown) that both natural and pharmaceutical iron chelators might have useful protective roles in arresting cognitive decline, and that a further assessment of the role of microbes in AD development is more than highly warranted.
Collapse
Affiliation(s)
- Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, South Africa
| | - Janette Bester
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, South Africa
| | - Douglas B Kell
- School of Chemistry, The University of Manchester, Manchester, Lancs, UK.,The Manchester Institute of Biotechnology, The University of Manchester, Manchester, Lancs, UK.,Centre for Synthetic Biology of Fine and Speciality Chemicals, The University of Manchester, Manchester, Lancs, UK
| |
Collapse
|
23
|
Lopresti AL. The Problem of Curcumin and Its Bioavailability: Could Its Gastrointestinal Influence Contribute to Its Overall Health-Enhancing Effects? Adv Nutr 2018; 9:41-50. [PMID: 29438458 PMCID: PMC6333932 DOI: 10.1093/advances/nmx011] [Citation(s) in RCA: 185] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/08/2017] [Indexed: 12/19/2022] Open
Abstract
Curcumin, from the spice turmeric, exhibits anti-inflammatory, antioxidant, anticancer, antiviral, and neurotrophic activity and therefore holds promise as a therapeutic agent to prevent and treat several disorders. However, a major barrier to curcumin's clinical efficacy is its poor bioavailability. Efforts have therefore been dedicated to developing curcumin formulations with greater bioavailability and systemic tissue distribution. However, it is proposed in this review that curcumin's potential as a therapeutic agent may not solely rely on its bioavailability, but rather its medicinal benefits may also arise from its positive influence on gastrointestinal health and function. In this review, in vitro, animal, and human studies investigating the effects of curcumin on intestinal microbiota, intestinal permeability, gut inflammation and oxidative stress, anaphylactic response, and bacterial, parasitic, and fungal infections are summarized. It is argued that positive changes in these areas can have wide-ranging influences on both intestinal and extraintestinal diseases, and therefore presents as a possible mechanism behind curcumin's therapeutic efficacy.
Collapse
Affiliation(s)
- Adrian L Lopresti
- School of Psychology and Exercise Science, Murdoch University, Perth, Western Australia, Australia,Address correspondence to ALL (e-mail: )
| |
Collapse
|
24
|
Leheste JR, Ruvolo KE, Chrostowski JE, Rivera K, Husko C, Miceli A, Selig MK, Brüggemann H, Torres G. P. acnes-Driven Disease Pathology: Current Knowledge and Future Directions. Front Cell Infect Microbiol 2017; 7:81. [PMID: 28352613 PMCID: PMC5348501 DOI: 10.3389/fcimb.2017.00081] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 03/01/2017] [Indexed: 01/10/2023] Open
Abstract
This review discusses the biology and behavior of Propionibacterium acnes (P. acnes), a dominant bacterium species of the skin biogeography thought to be associated with transmission, recurrence and severity of disease. More specifically, we discuss the ability of P. acnes to invade and persist in epithelial cells and circulating macrophages to subsequently induce bouts of sarcoidosis, low-grade inflammation and metastatic cell growth in the prostate gland. Finally, we discuss the possibility of P. acnes infiltrating the brain parenchyma to indirectly contribute to pathogenic processes in neurodegenerative disorders such as those observed in Parkinson's disease (PD).
Collapse
Affiliation(s)
- Joerg R Leheste
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| | - Kathryn E Ruvolo
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| | - Joanna E Chrostowski
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| | - Kristin Rivera
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| | - Christopher Husko
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| | - Alyssa Miceli
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| | - Martin K Selig
- Molecular Pathology Division, Massachusetts General Hospital and Harvard Medical School Boston, MA, USA
| | | | - German Torres
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine Old Westbury, NY, USA
| |
Collapse
|
25
|
Sochocka M, Zwolińska K, Leszek J. The Infectious Etiology of Alzheimer's Disease. Curr Neuropharmacol 2017; 15:996-1009. [PMID: 28294067 PMCID: PMC5652018 DOI: 10.2174/1570159x15666170313122937] [Citation(s) in RCA: 212] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 03/06/2017] [Accepted: 03/06/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Inflammation is a part of the first line of defense of the body against invasive pathogens, and plays a crucial role in tissue regeneration and repair. A proper inflammatory response ensures the suitable resolution of inflammation and elimination of harmful stimuli, but when the inflammatory reactions are inappropriate it can lead to damage of the surrounding normal cells. The relationship between infections and Alzheimer's Disease (AD) etiology, especially lateonset AD (LOAD) has been continuously debated over the past three decades. METHODS This review discusses whether infections could be a causative factor that promotes the progression of AD and summarizes recent investigations associating infectious agents and chronic inflammation with AD. Preventive and therapeutic approaches to AD in the context of an infectious etiology of the disease are also discussed. RESULTS Emerging evidence supports the hypothesis of the role of neurotropic viruses from the Herpesviridae family, especially Human herpesvirus 1 (HHV-1), Cytomegalovirus (CMV), and Human herpesvirus 2 (HHV-2), in AD neuropathology. Recent investigations also indicate the association between Hepatitis C virus (HCV) infection and dementia. Among bacteria special attention is focused on spirochetes family and on periodontal pathogens such as Porphyromonas gingivalis or Treponema denticola that could cause chronic periodontitis and possibly contribute to the clinical onset of AD. CONCLUSION Chronic viral, bacterial and fungal infections might be causative factors for the inflammatory pathway in AD.
Collapse
Affiliation(s)
- Marta Sochocka
- Laboratory of Virology, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Katarzyna Zwolińska
- Laboratory of Virology, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
| | - Jerzy Leszek
- Department of Psychiatry, Wroclaw Medical University, Wroclaw, Poland
| |
Collapse
|
26
|
Zhan X, Stamova B, Jin LW, DeCarli C, Phinney B, Sharp FR. Gram-negative bacterial molecules associate with Alzheimer disease pathology. Neurology 2016; 87:2324-2332. [PMID: 27784770 PMCID: PMC5135029 DOI: 10.1212/wnl.0000000000003391] [Citation(s) in RCA: 320] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 08/24/2016] [Indexed: 12/19/2022] Open
Abstract
Objective: We determined whether Gram-negative bacterial molecules are associated with Alzheimer disease (AD) neuropathology given that previous studies demonstrate Gram-negative Escherichia coli bacteria can form extracellular amyloid and Gram-negative bacteria have been reported as the predominant bacteria found in normal human brains. Methods: Brain samples from gray and white matter were studied from patients with AD (n = 24) and age-matched controls (n = 18). Lipopolysaccharide (LPS) and E coli K99 pili protein were evaluated by Western blots and immunocytochemistry. Human brain samples were assessed for E coli DNA followed by DNA sequencing. Results: LPS and E coli K99 were detected immunocytochemically in brain parenchyma and vessels in all AD and control brains. K99 levels measured using Western blots were greater in AD compared to control brains (p < 0.01) and K99 was localized to neuron-like cells in AD but not control brains. LPS levels were also greater in AD compared to control brain. LPS colocalized with Aβ1-40/42 in amyloid plaques and with Aβ1-40/42 around vessels in AD brains. DNA sequencing confirmed E coli DNA in human control and AD brains. Conclusions: E coli K99 and LPS levels were greater in AD compared to control brains. LPS colocalized with Aβ1-40/42 in amyloid plaques and around vessels in AD brain. The data show that Gram-negative bacterial molecules are associated with AD neuropathology. They are consistent with our LPS-ischemia-hypoxia rat model that produces myelin aggregates that colocalize with Aβ and resemble amyloid-like plaques.
Collapse
Affiliation(s)
- Xinhua Zhan
- From the Department of Neurology (X.Z., B.S., C.D., F.R.S.), MIND Institute (X.Z., B.S., F.R.S.), Alzheimer's Disease Center (L.-W.J., C.D.), Department of Pathology (L.-W.J.), and Proteomics Core Facility, Genome Center (B.P.), University of California at Davis, Sacramento.
| | - Boryana Stamova
- From the Department of Neurology (X.Z., B.S., C.D., F.R.S.), MIND Institute (X.Z., B.S., F.R.S.), Alzheimer's Disease Center (L.-W.J., C.D.), Department of Pathology (L.-W.J.), and Proteomics Core Facility, Genome Center (B.P.), University of California at Davis, Sacramento
| | - Lee-Way Jin
- From the Department of Neurology (X.Z., B.S., C.D., F.R.S.), MIND Institute (X.Z., B.S., F.R.S.), Alzheimer's Disease Center (L.-W.J., C.D.), Department of Pathology (L.-W.J.), and Proteomics Core Facility, Genome Center (B.P.), University of California at Davis, Sacramento
| | - Charles DeCarli
- From the Department of Neurology (X.Z., B.S., C.D., F.R.S.), MIND Institute (X.Z., B.S., F.R.S.), Alzheimer's Disease Center (L.-W.J., C.D.), Department of Pathology (L.-W.J.), and Proteomics Core Facility, Genome Center (B.P.), University of California at Davis, Sacramento
| | - Brett Phinney
- From the Department of Neurology (X.Z., B.S., C.D., F.R.S.), MIND Institute (X.Z., B.S., F.R.S.), Alzheimer's Disease Center (L.-W.J., C.D.), Department of Pathology (L.-W.J.), and Proteomics Core Facility, Genome Center (B.P.), University of California at Davis, Sacramento
| | - Frank R Sharp
- From the Department of Neurology (X.Z., B.S., C.D., F.R.S.), MIND Institute (X.Z., B.S., F.R.S.), Alzheimer's Disease Center (L.-W.J., C.D.), Department of Pathology (L.-W.J.), and Proteomics Core Facility, Genome Center (B.P.), University of California at Davis, Sacramento
| |
Collapse
|
27
|
Nehls M. Unified theory of Alzheimer's disease (UTAD): implications for prevention and curative therapy. J Mol Psychiatry 2016; 4:3. [PMID: 27429752 PMCID: PMC4947325 DOI: 10.1186/s40303-016-0018-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/03/2016] [Indexed: 12/14/2022] Open
Abstract
The aim of this review is to propose a Unified Theory of Alzheimer's disease (UTAD) that integrates all key behavioural, genetic and environmental risk factors in a causal chain of etiological and pathogenetic events. It is based on three concepts that emanate from human's evolutionary history: (1) The grandmother-hypothesis (GMH), which explains human longevity due to an evolutionary advantage in reproduction by trans-generational transfer of acquired knowledge. Consequently it is argued that mental health at old-age must be the default pathway of humans' genetic program and not development of AD. (2) Therefore, mechanism like neuronal rejuvenation (NRJ) and adult hippocampal neurogenesis (AHN) that still function efficiently even at old age provide the required lifelong ability to memorize personal experiences important for survival. Cumulative evidence from a multitude of experimental and epidemiological studies indicate that behavioural and environmental risk factors, which impair productive AHN, result in reduced episodic memory performance and in reduced psychological resilience. This leads to avoidance of novelty, dysregulation of the hypothalamic-pituitary-adrenal (HPA)-axis and cortisol hypersecretion, which drives key pathogenic mechanisms of AD like the accumulation and oligomerization of synaptotoxic amyloid beta, chronic neuroinflammation and neuronal insulin resistance. (3) By applying to AHN the law of the minimum (LOM), which defines the basic requirements of biological growth processes, the UTAD explains why and how different lifestyle deficiencies initiate the AD process by impairing AHN and causing dysregulation of the HPA-axis, and how environmental and genetic risk factors such as toxins or ApoE4, respectively, turn into disease accelerators under these unnatural conditions. Consequently, the UTAD provides a rational strategy for the prevention of mental decline and a system-biological approach for the causal treatment of AD, which might even be curative if the systemic intervention is initiated early enough in the disease process. Hence an individualized system-biological treatment of patients with early AD is proposed as a test for the validity of UTAD and outlined in this review.
Collapse
Affiliation(s)
- Michael Nehls
- Independent Researcher, Allmendweg 1, 79279 Vörstetten, Germany
| |
Collapse
|
28
|
Pearson-Leary J, Osborne DM, McNay EC. Role of Glia in Stress-Induced Enhancement and Impairment of Memory. Front Integr Neurosci 2016; 9:63. [PMID: 26793072 PMCID: PMC4707238 DOI: 10.3389/fnint.2015.00063] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 12/05/2015] [Indexed: 12/20/2022] Open
Abstract
Both acute and chronic stress profoundly affect hippocampally-dependent learning and memory: moderate stress generally enhances, while chronic or extreme stress can impair, neural and cognitive processes. Within the brain, stress elevates both norepinephrine and glucocorticoids, and both affect several genomic and signaling cascades responsible for modulating memory strength. Memories formed at times of stress can be extremely strong, yet stress can also impair memory to the point of amnesia. Often overlooked in consideration of the impact of stress on cognitive processes, and specifically memory, is the important contribution of glia as a target for stress-induced changes. Astrocytes, microglia, and oligodendrocytes all have unique contributions to learning and memory. Furthermore, these three types of glia express receptors for both norepinephrine and glucocorticoids and are hence immediate targets of stress hormone actions. It is becoming increasingly clear that inflammatory cytokines and immunomodulatory molecules released by glia during stress may promote many of the behavioral effects of acute and chronic stress. In this review, the role of traditional genomic and rapid hormonal mechanisms working in concert with glia to affect stress-induced learning and memory will be emphasized.
Collapse
Affiliation(s)
- Jiah Pearson-Leary
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia Philadelphia, PA, USA
| | | | - Ewan C McNay
- Behavioral Neuroscience and Biology, University at Albany Albany, NY, USA
| |
Collapse
|
29
|
Comparison of the Effect of Exercise on Late-Phase LTP of the Dentate Gyrus and CA1 of Alzheimer's Disease Model. Mol Neurobiol 2015; 53:6859-6868. [PMID: 26660327 DOI: 10.1007/s12035-015-9612-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 12/03/2015] [Indexed: 01/15/2023]
Abstract
We investigated the neuroprotective effect of regular treadmill exercise training on long-term memory and its correlate: the late-phase long-term potentiation (L-LTP) and plasticity- and memory-related signaling molecules in the DG and CA1 areas of a rat model of Alzheimer's disease (AD) (i.c.v. infusion of Aβ1-42 peptides, 2 weeks, 250 pmol/day). Testing in the radial arm water maze revealed severe impairment of spatial long-term memory in Aβ-infused sedentary rats but not in exercised Aβ-infused rats. The L-LTP, measured as changes in the field (f)EPSP and in the amplitude of population spike (pspike), was induced by multiple high-frequency stimulation in the CA1 and DG areas of anesthetized rats. The L-LTP of fEPSP in both areas was severely impaired in the sedentary Aβ rats but not in exercised Aβ rats. However, L-LTP of the pspike was severely suppressed in the CA1 area but not in the DG of sedentary Aβ rats. Immunoblot analysis revealed no increase in the levels of phosphorylated (p)-CREB, CaMKIV, and brain-derived neurotrophic factor (BDNF) in both CA1 and DG areas of sedentary Aβ rats during L-LTP, whereas the levels of these molecules were robustly increased in exercised Aβ rats. Impairment of synaptic function may be due to deleterious changes in the molecular signaling cascades that mediate synaptic structural and functional changes. The protective effect of regular exercise can be a promising therapeutic measure for countering or delaying the AD-like pathology.
Collapse
|
30
|
Different Brain Regions are Infected with Fungi in Alzheimer's Disease. Sci Rep 2015; 5:15015. [PMID: 26468932 PMCID: PMC4606562 DOI: 10.1038/srep15015] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 09/15/2015] [Indexed: 12/23/2022] Open
Abstract
The possibility that Alzheimer's disease (AD) has a microbial aetiology has been proposed by several researchers. Here, we provide evidence that tissue from the central nervous system (CNS) of AD patients contain fungal cells and hyphae. Fungal material can be detected both intra- and extracellularly using specific antibodies against several fungi. Different brain regions including external frontal cortex, cerebellar hemisphere, entorhinal cortex/hippocampus and choroid plexus contain fungal material, which is absent in brain tissue from control individuals. Analysis of brain sections from ten additional AD patients reveals that all are infected with fungi. Fungal infection is also observed in blood vessels, which may explain the vascular pathology frequently detected in AD patients. Sequencing of fungal DNA extracted from frozen CNS samples identifies several fungal species. Collectively, our findings provide compelling evidence for the existence of fungal infection in the CNS from AD patients, but not in control individuals.
Collapse
|
31
|
Encyclopedia of bacterial gene circuits whose presence or absence correlate with pathogenicity--a large-scale system analysis of decoded bacterial genomes. BMC Genomics 2015; 16:773. [PMID: 26459834 PMCID: PMC4603813 DOI: 10.1186/s12864-015-1957-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 09/28/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Bacterial infections comprise a global health challenge as the incidences of antibiotic resistance increase. Pathogenic potential of bacteria has been shown to be context dependent, varying in response to environment and even within the strains of the same genus. RESULTS We used the KEGG repository and extensive literature searches to identify among the 2527 bacterial genomes in the literature those implicated as pathogenic to the host, including those which show pathogenicity in a context dependent manner. Using data on the gene contents of these genomes, we identified sets of genes highly abundant in pathogenic but relatively absent in commensal strains and vice versa. In addition, we carried out genome comparison within a genus for the seventeen largest genera in our genome collection. We projected the resultant lists of ortholog genes onto KEGG bacterial pathways to identify clusters and circuits, which can be linked to either pathogenicity or synergy. Gene circuits relatively abundant in nonpathogenic bacteria often mediated biosynthesis of antibiotics. Other synergy-linked circuits reduced drug-induced toxicity. Pathogen-abundant gene circuits included modules in one-carbon folate, two-component system, type-3 secretion system, and peptidoglycan biosynthesis. Antibiotics-resistant bacterial strains possessed genes modulating phagocytosis, vesicle trafficking, cytoskeletal reorganization, and regulation of the inflammatory response. Our study also identified bacterial genera containing a circuit, elements of which were previously linked to Alzheimer's disease. CONCLUSIONS Present study produces for the first time, a signature, in the form of a robust list of gene circuitry whose presence or absence could potentially define the pathogenicity of a microbiome. Extensive literature search substantiated a bulk majority of the commensal and pathogenic circuitry in our predicted list. Scanning microbiome libraries for these circuitry motifs will provide further insights into the complex and context dependent pathogenicity of bacteria.
Collapse
|
32
|
Olsen I, Singhrao SK. Can oral infection be a risk factor for Alzheimer's disease? J Oral Microbiol 2015; 7:29143. [PMID: 26385886 PMCID: PMC4575419 DOI: 10.3402/jom.v7.29143] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 07/21/2015] [Accepted: 08/21/2015] [Indexed: 12/19/2022] Open
Abstract
Alzheimer's disease (AD) is a scourge of longevity that will drain enormous resources from public health budgets in the future. Currently, there is no diagnostic biomarker and/or treatment for this most common form of dementia in humans. AD can be of early familial-onset or sporadic with a late-onset. Apart from the two main hallmarks, amyloid-beta and neurofibrillary tangles, inflammation is a characteristic feature of AD neuropathology. Inflammation may be caused by a local central nervous system insult and/or by peripheral infections. Numerous microorganisms are suspected in AD brains ranging from bacteria (mainly oral and non-oral Treponema species), viruses (herpes simplex type I), and yeasts (Candida species). A causal relationship between periodontal pathogens and non-oral Treponema species of bacteria has been proposed via the amyloid-beta and inflammatory links. Periodontitis constitutes a peripheral oral infection that can provide the brain with intact bacteria and virulence factors and inflammatory mediators due to daily, transient bacteremias. If and when genetic risk factors meet environmental risk factors in the brain, disease is expressed, in which neurocognition may be impacted, leading to the development of dementia. To achieve the goal of finding a diagnostic biomarker and possible prophylactic treatment for AD, there is an initial need to solve the etiological puzzle contributing to its pathogenesis. This review therefore addresses oral infection as the plausible etiology of late-onset AD (LOAD).
Collapse
Affiliation(s)
- Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway;
| | - Sim K Singhrao
- Oral & Dental Sciences Research Group, College of Clinical and Biomedical Sciences, University of Central Lancashire, Preston, UK
| |
Collapse
|
33
|
Lim SL, Rodriguez-Ortiz CJ, Kitazawa M. Infection, systemic inflammation, and Alzheimer's disease. Microbes Infect 2015; 17:549-56. [DOI: 10.1016/j.micinf.2015.04.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/13/2015] [Accepted: 04/14/2015] [Indexed: 12/13/2022]
|
34
|
Kell D, Potgieter M, Pretorius E. Individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology. F1000Res 2015; 4:179. [PMID: 26629334 PMCID: PMC4642849 DOI: 10.12688/f1000research.6709.2] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/04/2015] [Indexed: 01/28/2023] Open
Abstract
For bacteria, replication mainly involves growth by binary fission. However, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. They thereby evade detection by conventional culture-based methods. Such dormant cells may also be observed in laboratory cultures and in clinical microbiology. They are usually more tolerant to stresses such as antibiotics, and in clinical microbiology they are typically referred to as 'persisters'. Bacterial cultures necessarily share a great deal of relatedness, and inclusive fitness theory implies that there are conceptual evolutionary advantages in trading a variation in growth rate against its mean, equivalent to hedging one's bets. There is much evidence that bacteria exploit this strategy widely. We here bring together data that show the commonality of these phenomena across environmental, laboratory and clinical microbiology. Considerable evidence, using methods similar to those common in environmental microbiology, now suggests that many supposedly non-communicable, chronic and inflammatory diseases are exacerbated (if not indeed largely caused) by the presence of dormant or persistent bacteria (the ability of whose components to cause inflammation is well known). This dormancy (and resuscitation therefrom) often reflects the extent of the availability of free iron. Together, these phenomena can provide a ready explanation for the continuing inflammation common to such chronic diseases and its correlation with iron dysregulation. This implies that measures designed to assess and to inhibit or remove such organisms (or their access to iron) might be of much therapeutic benefit.
Collapse
Affiliation(s)
- Douglas Kell
- School of Chemistry and The Manchester Institute of Biotechnology, The University of Manchester, Manchester, Lancashire, M1 7DN, UK
| | - Marnie Potgieter
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
| | - Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
| |
Collapse
|
35
|
Kell D, Potgieter M, Pretorius E. Individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology. F1000Res 2015; 4:179. [PMID: 26629334 DOI: 10.12688/f1000research.6709.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/29/2015] [Indexed: 01/28/2023] Open
Abstract
For bacteria, replication mainly involves growth by binary fission. However, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. They thereby evade detection by conventional culture-based methods. Such dormant cells may also be observed in laboratory cultures and in clinical microbiology. They are usually more tolerant to stresses such as antibiotics, and in clinical microbiology they are typically referred to as 'persisters'. Bacterial cultures necessarily share a great deal of relatedness, and inclusive fitness theory implies that there are conceptual evolutionary advantages in trading a variation in growth rate against its mean, equivalent to hedging one's bets. There is much evidence that bacteria exploit this strategy widely. We here bring together data that show the commonality of these phenomena across environmental, laboratory and clinical microbiology. Considerable evidence, using methods similar to those common in environmental microbiology, now suggests that many supposedly non-communicable, chronic and inflammatory diseases are exacerbated (if not indeed largely caused) by the presence of dormant or persistent bacteria (the ability of whose components to cause inflammation is well known). This dormancy (and resuscitation therefrom) often reflects the extent of the availability of free iron. Together, these phenomena can provide a ready explanation for the continuing inflammation common to such chronic diseases and its correlation with iron dysregulation. This implies that measures designed to assess and to inhibit or remove such organisms (or their access to iron) might be of much therapeutic benefit.
Collapse
Affiliation(s)
- Douglas Kell
- School of Chemistry and The Manchester Institute of Biotechnology, The University of Manchester, Manchester, Lancashire, M1 7DN, UK
| | - Marnie Potgieter
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
| | - Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
| |
Collapse
|
36
|
Anastasio TJ. Computational identification of potential multi-drug combinations for reduction of microglial inflammation in Alzheimer disease. Front Pharmacol 2015; 6:116. [PMID: 26097457 PMCID: PMC4456568 DOI: 10.3389/fphar.2015.00116] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/19/2015] [Indexed: 12/31/2022] Open
Abstract
Like other neurodegenerative diseases, Alzheimer Disease (AD) has a prominent inflammatory component mediated by brain microglia. Reducing microglial inflammation could potentially halt or at least slow the neurodegenerative process. A major challenge in the development of treatments targeting brain inflammation is the sheer complexity of the molecular mechanisms that determine whether microglia become inflammatory or take on a more neuroprotective phenotype. The process is highly multifactorial, raising the possibility that a multi-target/multi-drug strategy could be more effective than conventional monotherapy. This study takes a computational approach in finding combinations of approved drugs that are potentially more effective than single drugs in reducing microglial inflammation in AD. This novel approach exploits the distinct advantages of two different computer programming languages, one imperative and the other declarative. Existing programs written in both languages implement the same model of microglial behavior, and the input/output relationships of both programs agree with each other and with data on microglia over an extensive test battery. Here the imperative program is used efficiently to screen the model for the most efficacious combinations of 10 drugs, while the declarative program is used to analyze in detail the mechanisms of action of the most efficacious combinations. Of the 1024 possible drug combinations, the simulated screen identifies only 7 that are able to move simulated microglia at least 50% of the way from a neurotoxic to a neuroprotective phenotype. Subsequent analysis shows that of the 7 most efficacious combinations, 2 stand out as superior both in strength and reliability. The model offers many experimentally testable and therapeutically relevant predictions concerning effective drug combinations and their mechanisms of action.
Collapse
Affiliation(s)
- Thomas J Anastasio
- Computational Neurobiology Laboratory, Department of Molecular and Integrative Physiology, Beckman Institute, University of Illinois at Urbana-Champaign Urbana, IL, USA
| |
Collapse
|