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Brown GC, Camacho M, Williams‐Gray CH. The Endotoxin Hypothesis of Parkinson's Disease. Mov Disord 2023; 38:1143-1155. [PMID: 37157885 PMCID: PMC10947365 DOI: 10.1002/mds.29432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/14/2023] [Accepted: 04/19/2023] [Indexed: 05/10/2023] Open
Abstract
The endotoxin hypothesis of Parkinson's disease (PD) is the idea that lipopolysaccharide (LPS) endotoxins contribute to the pathogenesis of this disorder. LPS endotoxins are found in, and released from, the outer membrane of Gram-negative bacteria, for example in the gut. It is proposed that gut dysfunction in early PD leads to elevated LPS levels in the gut wall and blood, which promotes both α-synuclein aggregation in the enteric neurons and a peripheral inflammatory response. Communication to the brain via circulating LPS and cytokines in the blood and/or the gut-brain axis leads to neuroinflammation and spreading of α-synuclein pathology, exacerbating neurodegeneration in brainstem nuclei and loss of dopaminergic neurons in the substantia nigra, and manifesting in the clinical symptoms of PD. The evidence supporting this hypothesis includes: (1) gut dysfunction, permeability, and bacterial changes occur early in PD, (2) serum levels of LPS are increased in a proportion of PD patients, (3) LPS induces α-synuclein expression, aggregation, and neurotoxicity, (4) LPS causes activation of peripheral monocytes leading to inflammatory cytokine production, and (5) blood LPS causes brain inflammation and specific loss of midbrain dopaminergic neurons, mediated by microglia. If the hypothesis is correct, then treatment options might include: (1) changing the gut microbiome, (2) reducing gut permeability, (3) reducing circulating LPS levels, or (4) blocking the response of immune cells and microglia to LPS. However, the hypothesis has a number of limitations and requires further testing, in particular whether reducing LPS levels can reduce PD incidence, progression, or severity. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Guy C. Brown
- Department of BiochemistryUniversity of CambridgeCambridgeUK
| | - Marta Camacho
- Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
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Elsasser TH, Ma B, Ravel J, Kahl S, Gajer P, Cross A. Short-term feeding of defatted bovine colostrum mitigates inflammation in the gut via changes in metabolites and microbiota in a chicken animal model. Anim Microbiome 2023; 5:6. [PMID: 36703224 PMCID: PMC9878500 DOI: 10.1186/s42523-023-00225-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 01/10/2023] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Nondrug supplement strategies to improve gut health have largely focused on the effects of individual compounds to improve one aspect of gut homeostasis. However, there is no comprehensive assessment of the reproducible effects of oral, short-term, low-level colostrum supplementation on gut inflammation status that are specific to the ileum. Herein, a chicken animal model highly responsive to even mild gut inflammatory stimuli was employed to compare the outcomes of feeding a standard diet (CON) to those of CON supplemented with a centrifuge-defatted bovine colostrum (BC) or a nonfat dried milk (NFDM) control on the efficiency of nutrient use, ileal morphology, gut nitro-oxidative inflammation status, metabolites, and the composition of the microbiota. RESULTS A repeated design, iterative multiple regression model was developed to analyze how BC affected ileal digesta-associated anti-inflammatory metabolite abundance coincident with observed changes in the ileal microbiome, mitigation of epithelial inflammation, and ileal surface morphology. An improved whole body nutrient use efficiency in the BC group (v CON and NFDM) coincided with the observed increased ileum absorptive surface and reduced epithelial cell content of tyrosine-nitrated protein (NT, biomarker of nitro-oxidative inflammatory stress). Metabolome analysis revealed that anti-inflammatory metabolites were significantly greater in abundance in BC-fed animals. BC also had a beneficial BC impact on microbiota, particularly in promoting the presence of the bacterial types associated with eubiosis and the segmented filamentous bacteria, Candidatus Arthromitus. CONCLUSION The data suggest that an anti-inflammatory environment in the ileum was more evident in BC than in the other feeding groups and associated with an increased content of statistically definable groups of anti-inflammatory metabolites that appear to functionally link the observed interactions between the host's improved gut health with an observed increase in whole body nutrient use efficiency, beneficial changes in the microbiome and immunometabolism.
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Affiliation(s)
- Ted H. Elsasser
- grid.463419.d0000 0001 0946 3608Animal Biosciences and Biotechnology Laboratory, USA Department of Agriculture (USDA), Agricultural Research Service (ARS), Beltsville, MD 20705 USA
| | - Bing Ma
- grid.411024.20000 0001 2175 4264Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201 USA
| | - Jacques Ravel
- grid.411024.20000 0001 2175 4264Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201 USA
| | - Stanislaw Kahl
- grid.463419.d0000 0001 0946 3608Animal Biosciences and Biotechnology Laboratory, USA Department of Agriculture (USDA), Agricultural Research Service (ARS), Beltsville, MD 20705 USA
| | - Pawel Gajer
- grid.411024.20000 0001 2175 4264Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD 21201 USA
| | - Alan Cross
- grid.411024.20000 0001 2175 4264Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201 USA
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Rainard P, Gilbert FB, Germon P, Foucras G. Invited review: A critical appraisal of mastitis vaccines for dairy cows. J Dairy Sci 2021; 104:10427-10448. [PMID: 34218921 DOI: 10.3168/jds.2021-20434] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/23/2021] [Indexed: 11/19/2022]
Abstract
Infections of the mammary gland remain a frequent disease of dairy ruminants that negatively affect animal welfare, milk quality, farmer serenity, and farming profitability and cause an increase in use of antimicrobials. There is a need for efficacious vaccines to alleviate the burden of mastitis in dairy farming, but this need has not been satisfactorily fulfilled despite decades of research. A careful appraisal of past and current research on mastitis vaccines reveals the peculiarities but also the commonalities among mammary gland infections associated with the major mastitis pathogens Escherichia coli, Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae, or Streptococcus dysgalactiae. A major pitfall is that the immune mechanisms of effective protection have not been fully identified. Until now, vaccine development has been directed toward the generation of antibodies. In this review, we drew up an inventory of the main approaches used to design vaccines that aim at the major pathogens for the mammary gland, and we critically appraised the current and tentative vaccines. In particular, we sought to relate efficacy to vaccine-induced defense mechanisms to shed light on some possible reasons for current vaccine shortcomings. Based on the lessons learned from past attempts and the recent results of current research, the design of effective vaccines may take a new turn in the years to come.
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Affiliation(s)
- Pascal Rainard
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, Infectiologie et Santé Publique, 37380 Nouzilly, France.
| | - Florence B Gilbert
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, Infectiologie et Santé Publique, 37380 Nouzilly, France
| | - Pierre Germon
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, Infectiologie et Santé Publique, 37380 Nouzilly, France
| | - Gilles Foucras
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Toulouse, École Nationale Vétérinaire de Toulouse, Interactions Hôtes-Agents Pathogènes, 31076 Toulouse, France
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Cross AS, Opal SM, Palardy JE, Shridhar S, Baliban SM, Scott AJ, Chahin AB, Ernst RK. A pilot study of an anti-endotoxin Ig-enriched bovine colostrum to prevent experimental sepsis. Innate Immun 2021; 27:266-274. [PMID: 33858243 PMCID: PMC8054147 DOI: 10.1177/17534259211007538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 03/08/2021] [Accepted: 03/16/2021] [Indexed: 12/04/2022] Open
Abstract
Despite the dramatic increase in antimicrobial resistance, there is a dearth of antibiotics in development and few pharmaceutical companies working in the field. Further, any new antibiotics are likely to have a short shelf life. Ab-based interventions offer alternatives that are not likely to be circumvented by the widely prevalent antibiotic resistance genes. Bovine colostrum (BC)-the first milk after parturition, rich in nutrients and immune components-promotes gut integrity and modulates the gut microbiome. We developed a hyperimmune BC (HBC) enriched in Abs to a highly conserved LOS core region of Gram-negative bacteria by immunizing pregnant cows with a vaccine comprised of detoxified LOS from Escherichia coli O111 Rc (J5) mutant non-covalently complexed to group B meningococcal outer membrane protein (J5dLOS/OMP). This vaccine generated robust levels of anti-J5 LOS Ab in the colostrum. When given orally to neutropenic rats challenged orally with Pseudomonas aeruginosa, administration of HBC improved survival compared to non-immune rats, while both BC preparations improved survival compared to PBS controls. Elevated circulating endotoxin levels correlated with mortality. HBC and to a lesser extent non-immune BC reduced bacterial burden from the liver, lung, and spleen. We conclude that HBC and to a lesser extent BC may be effective supplements that improve outcome from lethal gut-derived disseminated infection and may reduce transmission of Gram-negative bacilli from the gastrointestinal tract.
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Affiliation(s)
- Alan S Cross
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, USA
| | - Steven M Opal
- Division of Infectious Diseases, Rhode Island Hospital, USA
| | - John E Palardy
- Infectious Disease Division, Memorial Hospital of RI, USA
| | - Surekha Shridhar
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, USA
| | - Scott M Baliban
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, USA
| | - Alison J Scott
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, USA
| | | | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, USA
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Oyler BL, Khan MM, Smith DF, Harberts EM, Kilgour DPA, Ernst RK, Cross AS, Goodlett DR. Top Down Tandem Mass Spectrometric Analysis of a Chemically Modified Rough-Type Lipopolysaccharide Vaccine Candidate. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:1221-1229. [PMID: 29464544 PMCID: PMC8294406 DOI: 10.1007/s13361-018-1897-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/08/2018] [Accepted: 01/08/2018] [Indexed: 06/08/2023]
Abstract
Recent advances in lipopolysaccharide (LPS) biology have led to its use in drug discovery pipelines, including vaccine and vaccine adjuvant discovery. Desirable characteristics for LPS vaccine candidates include both the ability to produce a specific antibody titer in patients and a minimal host inflammatory response directed by the innate immune system. However, in-depth chemical characterization of most LPS extracts has not been performed; hence, biological activities of these extracts are unpredictable. Additionally, the most widely adopted workflow for LPS structure elucidation includes nonspecific chemical decomposition steps before analyses, making structures inferred and not necessarily biologically relevant. In this work, several different mass spectrometry workflows that have not been previously explored were employed to show proof-of-principle for top down LPS primary structure elucidation, specifically for a rough-type mutant (J5) E. coli-derived LPS component of a vaccine candidate. First, ion mobility filtered precursor ions were subjected to collision induced dissociation (CID) to define differences in native J5 LPS v. chemically detoxified J5 LPS (dLPS). Next, ultra-high mass resolving power, accurate mass spectrometry was employed for unequivocal precursor and product ion empirical formulae generation. Finally, MS3 analyses in an ion trap instrument showed that previous knowledge about dissociation of LPS components can be used to reconstruct and sequence LPS in a top down fashion. A structural rationale is also explained for differential inflammatory dose-response curves, in vitro, when HEK-Blue hTLR4 cells were administered increasing concentrations of native J5 LPS v. dLPS, which will be useful in future drug discovery efforts. Graphical Abstract ᅟ.
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Affiliation(s)
- Benjamin L Oyler
- School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
| | - Mohd M Khan
- School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
| | - Donald F Smith
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310, USA
| | - Erin M Harberts
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | - David P A Kilgour
- Chemistry and Forensics, School of Science and Technology, Nottingham Trent University, Nottingham, NG11 8NS, UK
| | - Robert K Ernst
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | - Alan S Cross
- Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, MD, 21201, USA
| | - David R Goodlett
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Pharmacy Hall North Room 623, 20 N. Pine St, Baltimore, MD, 21201, USA.
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