1
|
Abstract
The amoeba parasite Entamoeba histolytica is the causative agent of human amebiasis, an enteropathic disease affecting millions of people worldwide. This ancient protozoan is an elementary example of how parasites evolve with humans, e.g. taking advantage of multiple mechanisms to evade immune responses, interacting with microbiota for nutritional and protective needs, utilizing host resources for growth, division, and encystation. These skills of E. histolytica perpetuate the species and incidence of infection. However, in 10% of infected cases, the parasite turns into a pathogen; the host-parasite equilibrium is then disorganized, and the simple lifecycle based on two cell forms, trophozoites and cysts, becomes unbalanced. Trophozoites acquire a virulent phenotype which, when non-controlled, leads to intestinal invasion with the onset of amoebiasis symptoms. Virulent E. histolytica must cross mucus, epithelium, connective tissue and possibly blood. This highly mobile parasite faces various stresses and a powerful host immune response, with oxidative stress being a challenge for its survival. New emerging research avenues and omics technologies target gene regulation to determine human or parasitic factors activated upon infection, their role in virulence activation, and in pathogenesis; this research bears in mind that E. histolytica is a resident of the complex intestinal ecosystem. The goal is to eradicate amoebiasis from the planet, but the parasitic life of E. histolytica is ancient and complex and will likely continue to evolve with humans. Advances in these topics are summarized here.
Collapse
Affiliation(s)
- Nancy Guillén
- Cell Biology and Infection Department, Institut Pasteur and Centre National de la Recherche Scientifique CNRS-ERM9195, Paris, France
| |
Collapse
|
2
|
Gong H, Yuan Q, Du M, Mao X. Polar lipid-enriched milk fat globule membrane supplementation in maternal high-fat diet promotes intestinal barrier function and modulates gut microbiota in male offspring. Food Funct 2023; 14:10204-10220. [PMID: 37909908 DOI: 10.1039/d2fo04026c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Intestinal development plays a critical role in physiology and disease in early life and has long-term effects on the health status throughout the lifespan. Maternal high-fat diet (HFD) fuels the inflammatory reaction and metabolic syndrome, disrupts intestinal barrier function, and alters gut microbiota in offspring. The aim of this study was to evaluate whether polar lipid-enriched milk fat globule membrane (MFGM-PL) supplementation in maternal HFD could promote intestinal barrier function and modulate gut microbiota in male offspring. Obese female rats induced by HFD were supplemented with MFGM-PL during pregnancy and lactation. The offspring were fed HFD for 11 weeks after weaning. MFGM-PL supplementation to dams fed HFD decreased the body weight gain and ameliorated abnormalities of serum insulin, lipids, and inflammatory cytokines in offspring at weaning. Maternal MFGM-PL supplementation promoted the intestinal barrier by increasing the expression of Ki-67, lysozyme, mucin 2, zonula occludens-1, claudin-3, and occludin. Additionally, MFGM-PL supplementation to HFD dams improved gut dysbiosis in offspring. MFGM-PL increased the relative abundance of Akkermansiaceae, Ruminococcaceae, and Blautia. Concomitantly, maternal MFGM-PL treatment increased short-chain fatty acids of colonic contents and G-protein-coupled receptor (GPR) 41 and GPR 43 expressions in the colon of offspring. Importantly, the beneficial effects of maternal MFGM-PL intervention persisted to offspring's adulthood, as evidenced by increased relative abundance of norank_f_Muribaculaceae, Peptostreptococcaceae and Romboutsia and modulated the taxonomic diversity of gut microbiota in adult offspring. In summary, maternal MFGM-PL supplementation improved intestinal development in the offspring of dams fed with HFD, which exerted long-term beneficial effects on offspring intestinal health.
Collapse
Affiliation(s)
- Han Gong
- Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
| | - Qichen Yuan
- Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
| | - Min Du
- Department of Animal Sciences, Washington State University, Pullman, WA, USA
| | - Xueying Mao
- Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
| |
Collapse
|
3
|
Inaba R, Vujakovic S, Bergstrom K. The gut mucus network: A dynamic liaison between microbes and the immune system. Semin Immunol 2023; 69:101807. [PMID: 37478802 DOI: 10.1016/j.smim.2023.101807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 06/24/2023] [Accepted: 07/08/2023] [Indexed: 07/23/2023]
Abstract
A complex mucus network made up of large polymers of the mucin-family glycoprotein MUC2 exists between the large intestinal microbial mass and epithelial and immune cells. This has long been understood as an innate immune defense barrier against the microbiota and other luminal threats that reinforces the barrier function of the epithelium and limits microbiota contact with the tissues. However, past and recent studies have provided new evidence of how critical the mucus network is to act as a 'liaison' between host and microbe to mediate anti-inflammatory, mutualistic interactions with the microbiota and protection from pathogens. This review summarizes historical and recent insights into the formation of the gut mucus network, how the microbes and immune system influence mucus, and in turn, how the mucus influences immune responses to the microbiota.
Collapse
Affiliation(s)
- Rain Inaba
- Department of Biology, University of British Columbia, Okanagan Campus, 3187 University Way, Kelowna V1V 1V7, British Columbia, Canada
| | - Sara Vujakovic
- Department of Biology, University of British Columbia, Okanagan Campus, 3187 University Way, Kelowna V1V 1V7, British Columbia, Canada
| | - Kirk Bergstrom
- Department of Biology, University of British Columbia, Okanagan Campus, 3187 University Way, Kelowna V1V 1V7, British Columbia, Canada.
| |
Collapse
|
4
|
Gorman H, Moreau F, Dufour A, Chadee K. IgGFc-binding protein and MUC2 mucin produced by colonic goblet-like cells spatially interact non-covalently and regulate wound healing. Front Immunol 2023; 14:1211336. [PMID: 37359538 PMCID: PMC10285406 DOI: 10.3389/fimmu.2023.1211336] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 05/30/2023] [Indexed: 06/28/2023] Open
Abstract
The colonic mucus bilayer is the first line of innate host defense that at the same time houses and nourishes the commensal microbiota. The major components of mucus secreted by goblet cells are MUC2 mucin and the mucus-associated protein, FCGBP (IgGFc-binding protein). In this study, we determine if FCGBP and MUC2 mucin were biosynthesized and interacted together to spatially enhance the structural integrity of secreted mucus and its role in epithelial barrier function. MUC2 and FCGBP were coordinately regulated temporally in goblet-like cells and in response to a mucus secretagogue but not in CRISPR-Cas9 gene-edited MUC2 KO cells. Whereas ~85% of MUC2 was colocalized with FCGBP in mucin granules, ~50% of FCGBP was diffusely distributed in the cytoplasm of goblet-like cells. STRING-db v11 analysis of the mucin granule proteome revealed no protein-protein interaction between MUC2 and FCGBP. However, FCGBP interacted with other mucus-associated proteins. FCGBP and MUC2 interacted via N-linked glycans and were non-covalently bound in secreted mucus with cleaved low molecular weight FCGBP fragments. In MUC2 KO, cytoplasmic FCGBP was significantly increased and diffusely distributed in wounded cells that healed by enhanced proliferation and migration within 2 days, whereas, in WT cells, MUC2 and FCGBP were highly polarized at the wound margin which impeded wound closure by 6 days. In DSS colitis, restitution and healed lesions in Muc2+/+ but not Muc2-/- littermates, were accompanied by a rapid increase in Fcgbp mRNA and delayed protein expression at 12- and 15-days post DSS, implicating a potential novel endogenous protective role for FCGBP in wound healing to maintain epithelial barrier function.
Collapse
Affiliation(s)
- Hayley Gorman
- Department of Microbiology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
- Department of Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - France Moreau
- Department of Microbiology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
- Department of Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - Antoine Dufour
- Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
- Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Kris Chadee
- Department of Microbiology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
- Department of Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
5
|
Ma X, Yan H, Hong S, Yu S, Gong Y, Wu D, Li Y, Xiao H. Gamma-Aminobutyric Acid Promotes Beige Adipocyte Reconstruction by Modulating the Gut Microbiota in Obese Mice. Nutrients 2023; 15:nu15020456. [PMID: 36678326 PMCID: PMC9864545 DOI: 10.3390/nu15020456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Given the increasing prevalence of obesity, the white-to-beige adipocyte conversion has attracted interest as a target for obesity treatment. Gamma-aminobutyric acid (GABA) treatment can reduce obesity, but the underlying mechanism remains unclear. Here, we aimed to investigate the mechanism by which GABA triggers weight loss by improving the beiging of inguinal white adipose tissue (iWAT) and the role of gut microbiota in this process. The results showed that GABA reduced body weight and adipose inflammation and promoted the expression of thermogenic genes in the iWAT. The 16S rRNA sequence analysis of gut microbiota showed that GABA treatment increased the relative abundance of Bacteroidetes, Akkermansia, and Romboutsia and reduced that of Firmicutes and Erysipelatoclostridium in obese mice. Additionally, serum metabolomic analysis revealed that GABA treatment increased 3-hydroxybutyrate and reduced oxidized lipid levels in obese mice. Spearman's correlation analysis showed that Akkermansia and Romboutsia were negatively associated with the levels of oxidized lipids. Fecal microbiota transplantation analysis confirmed that the gut microbiota was involved in the white-to-beige adipocyte reconstruction by GABA. Overall, our findings suggest that GABA treatment may promote iWAT beiging through the gut microbiota in obese mice. GABA may be utilized to protect obese people against metabolic abnormalities brought on by obesity and gut dysbiosis.
Collapse
Affiliation(s)
- Xiaoyi Ma
- Department of Endocrinology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Huanhuan Yan
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Shubin Hong
- Department of Endocrinology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Shuang Yu
- Department of Endocrinology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Yingying Gong
- Department of Geriatrics, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Dide Wu
- Department of Endocrinology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Yanbing Li
- Department of Endocrinology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Haipeng Xiao
- Department of Endocrinology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
- Correspondence:
| |
Collapse
|
6
|
Wander K, Fujita M, Mattison SM, Duris M, Gauck M, Hopt T, Lacy K, Foligno A, Ulloa R, Dodge C, Mowo F, Kiwelu I, Mmbaga BT. Tradeoffs in milk immunity affect infant infectious disease risk. Evol Med Public Health 2022; 10:295-304. [PMID: 35769951 PMCID: PMC9233416 DOI: 10.1093/emph/eoac020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 05/10/2022] [Indexed: 11/22/2022] Open
Abstract
Background and objectives The human immune system has evolved to balance protection against infection with control of immune-mediated damage and tolerance of commensal microbes. Such tradeoffs between protection and harm almost certainly extend to the immune system of milk. Methodology Among breastfeeding mother–infant dyads in Kilimanjaro, Tanzania, we characterized in vitro proinflammatory milk immune responses to Salmonella enterica (an infectious agent) and Escherichia coli (a benign target) as the increase in interleukin-6 after 24 h of incubation with each bacterium. We characterized incident infectious diseases among infants through passive monitoring. We used Cox proportional hazards models to describe associations between milk immune activity and infant infectious disease. Results Among infants, risk for respiratory infections declined with increasing milk in vitro proinflammatory response to S. enterica (hazard ratio [HR]: 0.68; 95% confidence interval [CI]: 0.54, 0.86; P: 0.001), while risk for gastrointestinal infections increased with increasing milk in vitro proinflammatory response to E. coli (HR: 1.44; 95% CI: 1.05, 1.99; P: 0.022). Milk proinflammatory responses to S. enterica and E. coli were positively correlated (Spearman’s rho: 0.60; P: 0.000). Conclusions and implications These findings demonstrate a tradeoff in milk immune activity: the benefits of appropriate proinflammatory activity come at the hazard of misdirected proinflammatory activity. This tradeoff is likely to affect infant health in complex ways, depending on prevailing infectious disease conditions. How mother–infant dyads optimize proinflammatory milk immune activity should be a central question in future ecological–evolutionary studies of the immune system of milk.
Collapse
Affiliation(s)
- Katherine Wander
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Masako Fujita
- Department of Anthropology, Michigan State University , East Lansing, MI, USA
| | - Siobhan M Mattison
- Department of Anthropology, University of New Mexico , Albuquerque, NM, USA
| | - Margaret Duris
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Megan Gauck
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Tessa Hopt
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Katherine Lacy
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Angela Foligno
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Rebecca Ulloa
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Connor Dodge
- Department of Anthropology, Binghamton University (SUNY) , Binghamton, NY, USA
| | - Frida Mowo
- Kilimanjaro Christian Medical Centre , Moshi, Kilimanjaro, Tanzania
- Kilimanjaro Christian Medical University College , Moshi, Kilimanjaro, Tanzania
| | - Ireen Kiwelu
- Kilimanjaro Christian Medical Centre , Moshi, Kilimanjaro, Tanzania
- Kilimanjaro Christian Medical University College , Moshi, Kilimanjaro, Tanzania
- Kilimanjaro Clinical Research Institute , Moshi, Kilimanjaro, Tanzania
| | - Blandina T Mmbaga
- Kilimanjaro Christian Medical Centre , Moshi, Kilimanjaro, Tanzania
- Kilimanjaro Christian Medical University College , Moshi, Kilimanjaro, Tanzania
- Kilimanjaro Clinical Research Institute , Moshi, Kilimanjaro, Tanzania
- Duke Global Health Institute, Duke University , Durham, NC, USA
| |
Collapse
|
7
|
Farzi A, Ip CK, Reed F, Enriquez R, Zenz G, Durdevic M, Zhang L, Holzer P, Herzog H. Lack of peptide YY signaling in mice disturbs gut microbiome composition in response to high-fat diet. FASEB J 2021; 35:e21435. [PMID: 33749879 PMCID: PMC8251710 DOI: 10.1096/fj.202002215r] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/21/2021] [Accepted: 01/28/2021] [Indexed: 12/17/2022]
Abstract
Peptide YY (PYY), produced by endocrine L cells in the gut, is known for its critical role in regulating gastrointestinal functions as well as satiety. However, how these processes are integrated with maintaining a healthy gut microbiome composition is unknown. Here, we show that lack of PYY in mice leads to distinct changes in gut microbiome composition that are diet‐dependent. While under chow diet only slight differences in gut microbiome composition could be observed, high‐fat diet (HFD) aggravated these differences. Specifically an increased abundance of the Bacteroidetes phylum with a corresponding decrease of the Firmicutes/Bacteroidetes ratio could be detected in Pyy‐knockout (KO) mice in response to HFD. Detailed analysis of the Bacteroidetes phylum further revealed that the Alistipes genus belonging to the Rikenellaceae family, the Parabacteroides belonging to the Tannerellaceae family, as well as Muribaculum were increased in Pyy‐KO mice. In order to investigate whether these changes are associated with changed markers of gut barrier and immunity, we analyzed the colonic expression of various pro‐inflammatory cytokines, as well as tight junction proteins and mucin 2, and identified increased mRNA expression of the tight junction proteins Cldn2 and Ocel1 in Pyy‐KO mice, while pro‐inflammatory cytokine expression was not significantly altered. Together these results highlight a critical gene‐environment interaction between diet and the gut microbiome and its impact on homeostasis of the intestinal epithelium under conditions of reduced PYY signaling which is commonly seen under obese conditions.
Collapse
Affiliation(s)
- Aitak Farzi
- Neuroscience Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, NSW, Australia.,Division of Pharmacology, Otto Loewi Research Center, Medical University of Graz, Graz, Austria
| | - Chi Kin Ip
- Neuroscience Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, NSW, Australia.,Faculty of Medicine, University of NSW, Sydney, NSW, Australia
| | - Felicia Reed
- Neuroscience Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Ronaldo Enriquez
- Neuroscience Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, NSW, Australia
| | - Geraldine Zenz
- Division of Pharmacology, Otto Loewi Research Center, Medical University of Graz, Graz, Austria
| | - Marija Durdevic
- Center for Medical Research, Medical University of Graz, Graz, Austria.,Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria.,Theodor Escherich Laboratory for Medical Microbiome Research, Medical University of Graz, Graz, Austria
| | - Lei Zhang
- Neuroscience Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, NSW, Australia.,Faculty of Medicine, University of NSW, Sydney, NSW, Australia
| | - Peter Holzer
- Division of Pharmacology, Otto Loewi Research Center, Medical University of Graz, Graz, Austria
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, St. Vincent's Hospital, Darlinghurst, NSW, Australia.,Faculty of Medicine, University of NSW, Sydney, NSW, Australia
| |
Collapse
|
8
|
Ma X, Xiao W, Li H, Pang P, Xue F, Wan L, Pei L, Yan H. Metformin restores hippocampal neurogenesis and learning and memory via regulating gut microbiota in the obese mouse model. Brain Behav Immun 2021; 95:68-83. [PMID: 33609653 DOI: 10.1016/j.bbi.2021.02.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 02/10/2021] [Accepted: 02/11/2021] [Indexed: 12/26/2022] Open
Abstract
Numerous studies have shown that over-nutritional obesity may lead to pre-diabetes, type 2 diabetes and cognitive decline. As the degree of metabolic disorders increases, the cognitive decline is getting worse. However, the cellular events that cause this cognitive dysfunction is yet to be clarified. We used a high-fat diet (HFD) consumption-induced obesity mouse model to test the effects of metformin on the hippocampal neurogenesis and learning and memory abilities of obese mice. 5-Bromo-2'-deoxyuridine (BrdU) labelling and retrovirus labeling were applied to detect hippocampal newborn neurons. Behavioral experiments were used to detect learning and memory abilities of mice. 16S rRNA gene sequencing was performed to detect the composition of gut microbiota. The positron emission tomography (PET) was conducted to detect the energy metabolism activity of different mouse brain regions. Our results reveal that metformin restores the impairment of neurogenesis in the dentate gyrus and finally prevents the cognitive decline of the obese mice. Moreover, the therapeutic effects of metformin are achieved by regulating the composition of gut microbiota of mice, which may inhibit microglia activation and neuroinflammation in the brain of obese mice. This study suggests that metformin may be taken as a promising candidate for the intervention of cognitive decline related to imbalance of gut microbiota caused by obesity.
Collapse
Affiliation(s)
- Xiaoyi Ma
- Department of Endocrinology, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China
| | - Wenchang Xiao
- Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan 430074, China
| | - Hao Li
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Pei Pang
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan 430030, China; Department of Pathology, the First Affiliated Hospital of Soochow University, Suzhou 215000, China
| | - Feixiao Xue
- Department of Laboratory, Xi'an No.3 Hospital, Xi'an 710018, China
| | - Lu Wan
- Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan 430074, China
| | - Lei Pei
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan 430030, China; Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; Departments of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Huanhuan Yan
- Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology (HUST), Wuhan 430074, China; Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan 430030, China.
| |
Collapse
|
9
|
Uribe-Querol E, Rosales C. Immune Response to the Enteric Parasite Entamoeba histolytica. Physiology (Bethesda) 2021; 35:244-260. [PMID: 32490746 DOI: 10.1152/physiol.00038.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Entamoeba histolytica is a protozoan parasite responsible for amoebiasis, a disease with a high prevalence in developing countries. Establishing an amoebic infection involves interplay between pathogenic factors for invasion and tissue damage, and immune responses for protecting the host. Here, we review the pathogenicity of E. histolytica and summarize the latest knowledge on immune response and immune evasion mechanisms during amoebiasis.
Collapse
Affiliation(s)
- Eileen Uribe-Querol
- División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Carlos Rosales
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| |
Collapse
|
10
|
Rosales C. Neutrophils vs. amoebas: Immunity against the protozoan parasite Entamoeba histolytica. J Leukoc Biol 2021; 110:1241-1252. [PMID: 34085314 DOI: 10.1002/jlb.4mr0521-849rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/08/2021] [Accepted: 05/10/2021] [Indexed: 12/29/2022] Open
Abstract
Entamoeba histolytica is a protozoan parasite with high prevalence in developing countries, and causes amoebiasis. This disease affects the intestine and the liver, and is the third leading cause of human deaths among parasite infections. E. histolytica infection of the intestine or liver is associated with a strong inflammation characterized by a large number of infiltrating neutrophils. Consequently, several reports suggest that neutrophils play a protective role in amoebiasis. However, other reports indicate that amoebas making direct contact with neutrophils provoke lysis of these leukocytes, resulting in the release of their lytic enzymes, which in turn provoke tissue damage. Therefore, the role of neutrophils in this parasitic infection remains controversial. Neutrophils migrate from the circulation to sites of infection, where they display several antimicrobial functions, including phagocytosis, degranulation, and formation of neutrophil extracellular traps (NET). Recently, it was found that E. histolytica trophozoites are capable of inducing NET formation. Neutrophils in touch with amoebas launched NET in an explosive manner around the amoebas and completely covered them in nebulous DNA and cell aggregates where parasites got immobilized and killed. In addition, the phenotype of neutrophils can be modified by the microbiome resulting in protection against amoebas. This review describes the mechanisms of E. histolytica infection and discusses the novel view of how neutrophils are involved in innate immunity defense against amoebiasis. Also, the mechanisms on how the microbiome modulates neutrophil function are described.
Collapse
Affiliation(s)
- Carlos Rosales
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| |
Collapse
|
11
|
Han X, Mslati MA, Davies E, Chen Y, Allaire JM, Vallance BA. Creating a More Perfect Union: Modeling Intestinal Bacteria-Epithelial Interactions Using Organoids. Cell Mol Gastroenterol Hepatol 2021; 12:769-782. [PMID: 33895425 PMCID: PMC8273413 DOI: 10.1016/j.jcmgh.2021.04.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 02/08/2023]
Abstract
Intestinal organoids have become indispensable tools for many gastrointestinal researchers, advancing their studies of nontransformed intestinal epithelial cells, and their roles in an array of diseases, including inflammatory bowel disease and colon cancer. In many cases. these diseases, as well as many enteric infections, reflect pathogenic interactions between bacteria and the gut epithelium. The complexity of studying this microbe-epithelial interface in vivo has led to significant focus on modeling this cross-talk using organoid models. Considering how quickly the organoid field is advancing, it can be difficult to keep up to date with the latest techniques, as well as their respective strengths and weaknesses. This review addresses the advantages of using organoids derived from adult stem cells and the recently identified differences that biopsy location and patient age can have on organoids and their interactions with microbes. Several approaches to introducing bacteria in a relevant (apical) manner (ie, microinjecting 3-dimensional spheroids, polarity-reversed organoids, and 2-dimensional monolayers) also are addressed, as are the key readouts that can be obtained using these models. Lastly, the potential for new approaches, such as air-liquid interface, to facilitate studying bacterial interactions with important but understudied epithelial subsets such as goblet cells and their products, is evaluated.
Collapse
Affiliation(s)
- Xiao Han
- Department of Pediatrics, British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Matthias A Mslati
- Department of Pediatrics, British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Emily Davies
- Department of Pediatrics, British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Yan Chen
- Department of Pediatrics, British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Joannie M Allaire
- Department of Pediatrics, British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Bruce A Vallance
- Department of Pediatrics, British Columbia Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
| |
Collapse
|
12
|
NLRP6-associated host microbiota composition impacts in the intestinal barrier to systemic dissemination of Brucella abortus. PLoS Negl Trop Dis 2021; 15:e0009171. [PMID: 33617596 PMCID: PMC7932538 DOI: 10.1371/journal.pntd.0009171] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 03/04/2021] [Accepted: 01/25/2021] [Indexed: 02/07/2023] Open
Abstract
Brucella abortus is a Gram-negative bacterium responsible for a worldwide zoonotic infection—Brucellosis, which has been associated with high morbidity rate in humans and severe economic losses in infected livestock. The natural route of infection is through oral and nasal mucosa but the invasion process through host gut mucosa is yet to be understood. Studies have examined the role of NLRP6 (NOD-like receptor family pyrin domain-containing-6 protein) in gut homeostasis and defense against pathogens. Here, we investigated the impact of gut microbiota and NLRP6 in a murine model of Ba oral infection. Nlrp6-/- and wild-type (WT) mice were infected by oral gavage with Ba and tissues samples were collected at different time points. Our results suggest that Ba oral infection leads to significant alterations in gut microbiota. Moreover, Nlrp6-/- mice were more resistant to infection, with decreased CFU in the liver and reduction in gut permeability when compared to the control group. Fecal microbiota transplantation from WT and Nlrp6-/- into germ-free mice reflected the gut permeability phenotype from the donors. Additionally, depletion of gut microbiota by broad-spectrum-antibiotic treatment prevented Ba replication in WT while favoring bacterial growth in Nlrp6-/-. Finally, we observed higher eosinophils in the gut and leukocytes in the blood of infected Nlrp6-/- compared to WT-infected mice, which might be associated to the Nlrp6-/- resistance phenotype. Altogether, these results indicated that gut microbiota composition is the major factor involved in the initial stages of pathogen host replication and partially also by the resistance phenotype observed in Nlrp6 -/- mice regulating host inflammation against Ba infection. Brucella abortus (Ba) is an intracellular bacterium that causes zoonotic and clinical problems worldwide. Although the common route of infection is through oral and nasal, the mechanisms toward the gastrointestinal mucosa response is still unexplored. It is well known that microbiota promotes and maintains host intestinal homeostasis during bacterial infections. However, mechanisms by which the gut microbiota affects the Ba infection have not yet been demonstrated. Here, we provide significant insights into the relationship between gut microbiota and B. abortus oral infection and demonstrate the gut microbiota contribution to the gut permeability and dissemination of Ba. Furthermore, we investigated the participation of the gut microbiota from Nlrp6 deficient mice, on the gut permeability and Ba infection. Substantial experiments performed, mostly in vivo, showed that gut microbiota alterations promote gut barrier disruption, as indicated by increased gut permeability after Ba oral infection. Thus, our work highlights the role of gut mucosal environment through gut microbiota and Nlrp6 molecule involved in host innate immune responses to Ba infection.
Collapse
|
13
|
Coleman OI, Haller D. Microbe-Mucus Interface in the Pathogenesis of Colorectal Cancer. Cancers (Basel) 2021; 13:cancers13040616. [PMID: 33557139 PMCID: PMC7913824 DOI: 10.3390/cancers13040616] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/18/2021] [Accepted: 01/27/2021] [Indexed: 12/24/2022] Open
Abstract
Overlying gastrointestinal epithelial cells is the transparent mucus layer that separates the lumen from the host. The dynamic mucus layer serves to lubricate the mucosal surface, to protect underlying epithelial cells, and as a transport medium between luminal contents and epithelial cells. Furthermore, it provides a habitat for commensal bacteria and signals to the underlying immune system. Mucins are highly glycosylated proteins, and their glycocode is tissue-specific and closely linked to the resident microbiota. Aberrant mucin expression and glycosylation are linked to chronic inflammation and gastrointestinal cancers, including colorectal cancer (CRC). Aberrant mucus production compromises the mucus layer and allows bacteria to come into close contact with the intestinal epithelium, potentially triggering unfavorable host responses and the subsequent development of tumors. Here, we review our current understanding of the interaction between the intestinal microbiota and mucus in healthy and CRC subjects. Deep knowledge of the intricate mechanisms of microbe-mucus interactions may contribute to the development of novel treatment strategies for CRC, in which a dysfunctional mucus layer is observed.
Collapse
Affiliation(s)
- Olivia I. Coleman
- Department of Nutrition and Immunology, School of Life Sciences, Technical University of Munich, 85354 Freising, Germany;
- Correspondence: ; Tel.: +49-08161-71-2375
| | - Dirk Haller
- Department of Nutrition and Immunology, School of Life Sciences, Technical University of Munich, 85354 Freising, Germany;
- ZIEL—Institute for Food & Health, Technical University of Munich, 85354 Freising, Germany
| |
Collapse
|
14
|
Mendoza Cavazos C, Knoll LJ. Entamoeba histolytica: Five facts about modeling a complex human disease in rodents. PLoS Pathog 2020; 16:e1008950. [PMID: 33180884 PMCID: PMC7660559 DOI: 10.1371/journal.ppat.1008950] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
| | - Laura J. Knoll
- University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
| |
Collapse
|
15
|
Uddin MJ, Leslie JL, Petri WA. Host Protective Mechanisms to Intestinal Amebiasis. Trends Parasitol 2020; 37:165-175. [PMID: 33502317 PMCID: PMC7840892 DOI: 10.1016/j.pt.2020.09.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/27/2020] [Accepted: 09/28/2020] [Indexed: 12/13/2022]
Abstract
The protozoan parasite Entamoeba histolytica is the causative agent of amebiasis, an infection that manifests as colitis and, in some cases, liver abscess. A better understanding of host protective factors is key to developing an effective remedy. Recently, significant advances have been made in understanding the mechanisms of MUC2 production by goblet cells upon amebic infection, regulation of antimicrobial peptide production by Paneth cells, the interaction of commensal microbiota with immune stimulation, and host genetics in conferring protection from amebiasis. In addition to host pathways that may serve as potential therapeutic targets, significant progress has also been made with respect to development of a vaccine against amebiasis. Here, we aim to highlight the current understanding and knowledge gaps critically.
Collapse
Affiliation(s)
- Md Jashim Uddin
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, USA
| | - Jhansi L Leslie
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, USA
| | - William A Petri
- Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia, Charlottesville, VA, USA.
| |
Collapse
|
16
|
Grondin JA, Kwon YH, Far PM, Haq S, Khan WI. Mucins in Intestinal Mucosal Defense and Inflammation: Learning From Clinical and Experimental Studies. Front Immunol 2020; 11:2054. [PMID: 33013869 PMCID: PMC7500085 DOI: 10.3389/fimmu.2020.02054] [Citation(s) in RCA: 191] [Impact Index Per Article: 47.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 07/28/2020] [Indexed: 12/24/2022] Open
Abstract
Throughout the gastrointestinal (GI) tract, a distinct mucus layer composed of highly glycosylated proteins called mucins plays an essential role in providing lubrication for the passage of food, participating in cell signaling pathways and protecting the host epithelium from commensal microorganisms and invading pathogens, as well as toxins and other environmental irritants. These mucins can be broadly classified into either secreted gel-forming mucins, those that provide the structural backbone for the mucus barrier, or transmembrane mucins, those that form the glycocalyx layer covering the underlying epithelial cells. Goblet cells dispersed among the intestinal epithelial cells are chiefly responsible for the synthesis and secretion of mucins within the gut and are heavily influenced by interactions with the immune system. Evidence from both clinical and animal studies have indicated that several GI conditions, including inflammatory bowel disease (IBD), colorectal cancer, and numerous enteric infections are accompanied by considerable changes in mucin quality and quantity. These changes include, but are not limited to, impaired goblet cell function, synthesis dysregulation, and altered post-translational modifications. The current review aims to highlight the structural and functional features as well as the production and immunological regulation of mucins and the impact these key elements have within the context of barrier function and host defense in intestinal inflammation.
Collapse
Affiliation(s)
- Jensine A Grondin
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Yun Han Kwon
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Parsa Mehraban Far
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Sabah Haq
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Waliul I Khan
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| |
Collapse
|
17
|
Ashour DS, Othman AA. Parasite-bacteria interrelationship. Parasitol Res 2020; 119:3145-3164. [PMID: 32748037 DOI: 10.1007/s00436-020-06804-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 07/06/2020] [Indexed: 12/18/2022]
Abstract
Parasites and bacteria have co-evolved with humankind, and they interact all the time in a myriad of ways. For example, some bacterial infections result from parasite-dwelling bacteria as in the case of Salmonella infection during schistosomiasis. Other bacteria synergize with parasites in the evolution of human disease as in the case of the interplay between Wolbachia endosymbiont bacteria and filarial nematodes as well as the interaction between Gram-negative bacteria and Schistosoma haematobium in the pathogenesis of urinary bladder cancer. Moreover, secondary bacterial infections may complicate several parasitic diseases such as visceral leishmaniasis and malaria, due to immunosuppression of the host during parasitic infections. Also, bacteria may colonize the parasitic lesions; for example, hydatid cysts and skin lesions of ectoparasites. Remarkably, some parasitic helminths and arthropods exhibit antibacterial activity usually by the release of specific antimicrobial products. Lastly, some parasite-bacteria interactions are induced as when using probiotic bacteria to modulate the outcome of a variety of parasitic infections. In sum, parasite-bacteria interactions involve intricate processes that never cease to intrigue the researchers. However, understanding and exploiting these interactions could have prophylactic and curative potential for infections by both types of pathogens.
Collapse
Affiliation(s)
- Dalia S Ashour
- Medical Parasitology Department, Faculty of Medicine, Tanta University, Tanta, 31527, Egypt.
| | - Ahmad A Othman
- Medical Parasitology Department, Faculty of Medicine, Tanta University, Tanta, 31527, Egypt
| |
Collapse
|
18
|
Welter BH, Walters HA, Temesvari LA. Reduced expression of a rhomboid protease, EhROM1, correlates with changes in the submembrane distribution and size of the Gal/GalNAc lectin subunits in the human protozoan parasite, Entamoeba histolytica. PLoS One 2020; 15:e0219870. [PMID: 32134930 PMCID: PMC7058331 DOI: 10.1371/journal.pone.0219870] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 02/17/2020] [Indexed: 11/23/2022] Open
Abstract
Entamoeba histolytica is a food- and waterborne parasite that causes amebic dysentery and amoebic liver abscesses. Adhesion is one of the most important virulence functions as it facilitates motility, colonization of host, destruction of host tissue, and uptake of nutrients by the parasite. The parasite cell surface adhesin, the Gal/GalNAc lectin, facilitates parasite-host interaction by binding to galactose or N-acetylgalactosamine residues on host components. It is composed of heavy (Hgl), intermediate (Igl), and light (Lgl) subunits. Igl is constitutively localized to lipid rafts (cholesterol-rich membrane domains), whereas Hgl and Lgl transiently associate with rafts. When all three subunits are localized to rafts, galactose-sensitive adhesion is enhanced. Thus, submembrane location may regulate the function of this adhesion. Rhomboid proteases are a conserved family of intramembrane proteases that also participate in the regulation of parasite-host interactions. In E. histolytica, one rhomboid protease, EhROM1, cleaves Hgl as a substrate, and knockdown of its expression inhibits parasite-host interactions. Since rhomboid proteases are found within membranes, it is not surprising that lipid composition regulates their activity and enzyme-substrate binding. Given the importance of the lipid environment for both rhomboid proteases and the Gal/GalNAc lectin, we sought to gain insight into the relationship between rhomboid proteases and submembrane location of the lectin in E. histolytica. We demonstrated that EhROM1, itself, is enriched in highly buoyant triton-insoluble membranes reminiscent of rafts. Reducing rhomboid protease activity, either pharmacologically or genetically, correlated with an enrichment of Hgl and Lgl in rafts. In a mutant cell line with reduced EhROM1 expression, there was also a significant augmentation of the level of all three Gal/GalNAc subunits on the cell surface and an increase in the molecular weight of Hgl and Lgl. Overall, the study provides insight into the molecular mechanisms governing parasite-host adhesion for this pathogen.
Collapse
Affiliation(s)
- Brenda H. Welter
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, United States of America
- Eukaryotic Pathogens Innovations Center (EPIC), Clemson University, Clemson, South Carolina, United States of America
| | - Heather A. Walters
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, United States of America
- Eukaryotic Pathogens Innovations Center (EPIC), Clemson University, Clemson, South Carolina, United States of America
| | - Lesly A. Temesvari
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, United States of America
- Eukaryotic Pathogens Innovations Center (EPIC), Clemson University, Clemson, South Carolina, United States of America
| |
Collapse
|
19
|
Entamoeba histolytica stimulates the alarmin molecule HMGB1 from macrophages to amplify innate host defenses. Mucosal Immunol 2020; 13:344-356. [PMID: 31772322 DOI: 10.1038/s41385-019-0233-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/22/2019] [Accepted: 11/07/2019] [Indexed: 02/04/2023]
Abstract
Even though Entamoeba histolytica (Eh)-induced host pro-inflammatory responses play a critical role in disease, we know very little about the host factors that regulate this response. Direct contact between host cell and Eh signify the highest level of danger, and to eliminate this threat, the host immune system elicits an augmented immune response. To understand the mechanisms of this response, we investigated the induction and release of the endogenous alarmin molecule high-mobility group box 1 (HMGB1) that act as a pro-inflammatory cytokine and chemoattractant during Eh infection. Eh in contact with macrophage induced a dose- and time-dependent secretion of HMGB1 in the absence of cell death. Secretion of HMGB1 was facilitated by Eh surface Gal-lectin-activated phosphoinositide 3-kinase and nuclear factor-κB signaling and up-regulation of histone acetyltransferase activity to trigger acetylated HMGB1 translocation from the nucleus. Unlike lipopolysaccharide, Eh-induced HMGB1 release was independent of caspase-1-mediated inflammasome and gasdermin D pores. In vivo, Eh inoculation in specific pathogen-free but not germ-free mice was associated with high levels of pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, and keratinocyte-derived chemokine, which was suppressed with HMGB1 neutralization. This study reveals that Eh-induced active secretion of the HMGB1 plays a key role in shaping the pro-inflammatory landscape critical in innate host defense against amebiasis.
Collapse
|
20
|
Increased intestinal permeability exacerbates sepsis through reduced hepatic SCD-1 activity and dysregulated iron recycling. Nat Commun 2020; 11:483. [PMID: 31980623 PMCID: PMC6981269 DOI: 10.1038/s41467-019-14182-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 12/15/2019] [Indexed: 12/12/2022] Open
Abstract
Inflammatory bowel disease is associated with changes in the mucosal barrier, increased intestinal permeability, and increased risk of infections and sepsis, but the underlying mechanisms are incompletely understood. Here, we show how continuous translocation of gut microbial components affects iron homeostasis and facilitates susceptibility to inflammation-associated sepsis. A sub-lethal dose of lipopolysaccharide results in higher mortality in Mucin 2 deficient (Muc2-/-) mice, and is associated with elevated circulatory iron load and increased bacterial translocation. Translocation of gut microbial components attenuates hepatic stearoyl CoA desaturase-1 activity, a key enzyme in hepatic de novo lipogenesis. The resulting reduction of hepatic saturated and unsaturated fatty acid levels compromises plasma membrane fluidity of red blood cells, thereby significantly reducing their life span. Inflammation in Muc2-/- mice alters erythrophagocytosis efficiency of splenic macrophages, resulting in an iron-rich milieu that promotes bacterial growth. Our study thus shows that increased intestinal permeability triggers a cascade of events resulting in increased bacterial growth and risk of sepsis.
Collapse
|
21
|
Entamoeba histolytica Interaction with Enteropathogenic Escherichia coli Increases Parasite Virulence and Inflammation in Amebiasis. Infect Immun 2019; 87:IAI.00279-19. [PMID: 31527129 DOI: 10.1128/iai.00279-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 08/26/2019] [Indexed: 01/01/2023] Open
Abstract
Epidemiological studies suggest frequent association of enteropathogenic bacteria with Entamoeba histolytica during symptomatic infection. In this study, we sought to determine if the interaction with enteropathogenic (EPEC) or nonpathogenic Escherichia coli (strain DH5α) could modify the virulence of E. histolytica to cause disease in animal models of amebiasis. In vitro studies showed a 2-fold increase in CaCo2 monolayer destruction when E. histolytica interacted with EPEC but not with E. coli DH5α for 2.5 h. This was associated with increased E. histolytica proteolytic activity as revealed by zymogram analysis and degradation of the E. histolytica CP-A1/5 (EhCP-A1/5) peptide substrate Z-Arg-Arg-pNC and EhCP4 substrate Z-Val-Val-Arg-AMC. Additionally, E. histolytica-EPEC interaction increased EhCP-A1, -A2, -A4, and -A5, Hgl, Apa, and Cox-1 mRNA expression. Despite the marked upregulation of E. histolytica virulence factors, nonsignificant macroscopic differences in amebic liver abscess development were observed at early stages in hamsters inoculated with either E. histolytica-EPEC or E. histolytica-E. coli DH5α. Histopathology of livers of E. histolytica-EPEC-inoculated animals revealed foci of acute inflammation 3 h postinoculation that progressively increased, producing large inflammatory reactions, ischemia, and necrosis with high expression of il-1β, ifn-γ, and tnf-α proinflammatory cytokine genes compared with that in livers of E. histolytica-E. coli DH5α-inoculated animals. In closed colonic loops from mice, intense inflammation was observed with E. histolytica-EPEC manifested by downregulation of Math1 mRNA with a corresponding increase in the expression of Muc2 mucin and proinflammatory cytokine genes il-6, il-12, and mcp-1 These results demonstrate that E. histolytica/EPEC interaction enhanced the expression and production of key molecules associated with E. histolytica virulence, critical in pathogenesis and progression of disease.
Collapse
|
22
|
Yamada S, Kanda Y. Retinoic acid promotes barrier functions in human iPSC-derived intestinal epithelial monolayers. J Pharmacol Sci 2019; 140:337-344. [DOI: 10.1016/j.jphs.2019.06.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 12/20/2022] Open
|
23
|
|
24
|
Etienne-Mesmin L, Chassaing B, Desvaux M, De Paepe K, Gresse R, Sauvaitre T, Forano E, de Wiele TV, Schüller S, Juge N, Blanquet-Diot S. Experimental models to study intestinal microbes–mucus interactions in health and disease. FEMS Microbiol Rev 2019; 43:457-489. [DOI: 10.1093/femsre/fuz013] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/31/2019] [Indexed: 02/06/2023] Open
Abstract
ABSTRACT
A close symbiotic relationship exists between the intestinal microbiota and its host. A critical component of gut homeostasis is the presence of a mucus layer covering the gastrointestinal tract. Mucus is a viscoelastic gel at the interface between the luminal content and the host tissue that provides a habitat to the gut microbiota and protects the intestinal epithelium. The review starts by setting up the biological context underpinning the need for experimental models to study gut bacteria-mucus interactions in the digestive environment. We provide an overview of the structure and function of intestinal mucus and mucins, their interactions with intestinal bacteria (including commensal, probiotics and pathogenic microorganisms) and their role in modulating health and disease states. We then describe the characteristics and potentials of experimental models currently available to study the mechanisms underpinning the interaction of mucus with gut microbes, including in vitro, ex vivo and in vivo models. We then discuss the limitations and challenges facing this field of research.
Collapse
Affiliation(s)
- Lucie Etienne-Mesmin
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Benoit Chassaing
- Neuroscience Institute, Georgia State University, 100 Piedmont Ave SE, Atlanta, GA 30303 , USA
- Institute for Biomedical Sciences, Georgia State University, 100 Piedmont Ave, Atlanta, GA 30303 , USA
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Kim De Paepe
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Raphaële Gresse
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Thomas Sauvaitre
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Evelyne Forano
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| | - Tom Van de Wiele
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Stephanie Schüller
- Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR7UQ, United Kingdom
| | - Nathalie Juge
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR7UQ, United Kingdom
| | - Stéphanie Blanquet-Diot
- Université Clermont Auvergne, INRA, MEDIS, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France
| |
Collapse
|
25
|
Abstract
Entamoeba histolytica (Eh) is a protozoan parasite of humans that colonizes the outer colonic mucus layer. Under conditions not fully understood, Eh breaches innate host defenses and invades the intestinal mucosa-causing amebic colitis and liver abscess. In asymptomatic infection, Eh interacts with and feeds on resident microbiota that forms biofilms on the outer colonic mucus layer. Despite the close association between Eh and commensal microbiota, we still lack basic knowledge on whether microbiota and/or their metabolites influence Eh virulence traits critical in disease pathogenesis. In the pathogenesis of intestinal amebiasis, Eh overcomes the protective mucus layer using a combination of mucinase/glycosidase and potent mucus secretagogue activity. In this addendum, we discuss the interconnected role of a healthy mucus barrier and the role commensal microbiota play in shaping innate host defense against Eh-induced pro-inflammatory and secretory responses critical in disease pathogenesis.
Collapse
Affiliation(s)
- Aralia Leon-Coria
- Department of Microbiology, Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Manish Kumar
- Department of Microbiology, Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Kris Chadee
- Department of Microbiology, Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada,CONTACT Kris Chadee Department of Microbiology, Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| |
Collapse
|