251
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Cheng WY, Wu CY, Yu J. The role of gut microbiota in cancer treatment: friend or foe? Gut 2020; 69:1867-1876. [PMID: 32759302 PMCID: PMC7497589 DOI: 10.1136/gutjnl-2020-321153] [Citation(s) in RCA: 186] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 12/11/2022]
Abstract
The gut microbiota has been implicated in cancer and shown to modulate anticancer drug efficacy. Altered gut microbiota is associated with resistance to chemo drugs or immune checkpoint inhibitors (ICIs), whereas supplementation of distinct bacterial species restores responses to the anticancer drugs. Accumulating evidence has revealed the potential of modulating the gut microbiota to enhance the efficacy of anticancer drugs. Regardless of the valuable findings by preclinical models and clinical data of patients with cancer, a more thorough understanding of the interactions of the microbiota with cancer therapy helps researchers identify novel strategy for cancer prevention, stratify patients for more effective treatment and reduce treatment complication. In this review, we discuss the scientific evidence on the role of gut microbiota in cancer treatment, and highlight the latest knowledge and technologies leveraged to target specific bacteria that contribute to tumourigenesis. First, we provide an overview of the role of the gut microbiota in cancer, establishing the links between bacteria, inflammation and cancer treatment. Second, we highlight the mechanisms used by distinct bacterial species to modulate cancer growth, immune responses, as well as the efficacy of chemotherapeutic drugs and ICIs. Third, we demonstrate various approaches to modulate the gut microbiota and their potential in translational research. Finally, we discuss the limitations of current microbiome research in the context of cancer treatment, ongoing efforts to overcome these challenges and future perspectives.
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Affiliation(s)
- Wing Yin Cheng
- State Key Laboratory of Digestive Disease, Institute of Digestive Disease and The Department of Medicine and Therapeutics, Li Ka Shing Institute of Health Sciences, CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Chun-Ying Wu
- Division of Translational Research, Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Biomedical Bioinformatics and School of Medicine, National Yang-Ming University, Taipei, Taiwan; College of Public Health and Graduate Institute of Clinical Medicine, China Medical University, Taichung, Taiwan
| | - Jun Yu
- State Key Laboratory of Digestive Disease, Institute of Digestive Disease and The Department of Medicine and Therapeutics, Li Ka Shing Institute of Health Sciences, CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong SAR, China
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252
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Al Othaim A, Marasini D, Carbonero F. Impact of increasing concentration of tart and sweet cherries juices concentrates on healthy mice gut microbiota. FOOD FRONTIERS 2020. [DOI: 10.1002/fft2.46] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Ayoub Al Othaim
- Cell and Molecular Biology Program University of Arkansas Fayetteville Arkansas
- Department of Medical Laboratories College of Applied Medical Sciences Majmaah University Al‐Majmaah Saudi Arabia
| | - Daya Marasini
- Department of Food Science University of Arkansas Fayetteville Arkansas
- Weems Design Studio Inc. Suwanee Georgia
| | - Franck Carbonero
- Cell and Molecular Biology Program University of Arkansas Fayetteville Arkansas
- Department of Food Science University of Arkansas Fayetteville Arkansas
- Department of Nutrition and Exercise Physiology Elson Floyd School of Medicine Washington State University–Spokane Spokane Washington
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253
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Houttu V, Boulund U, Grefhorst A, Soeters MR, Pinto-Sietsma SJ, Nieuwdorp M, Holleboom AG. The role of the gut microbiome and exercise in non-alcoholic fatty liver disease. Therap Adv Gastroenterol 2020; 13:1756284820941745. [PMID: 32973925 PMCID: PMC7495942 DOI: 10.1177/1756284820941745] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 06/08/2020] [Indexed: 02/04/2023] Open
Abstract
In recent years, the human gut microbiome has been found to influence a multitude of non-communicable diseases such as cardiovascular disease and metabolic syndrome, with its components type 2 diabetes mellitus and obesity. It is recognized to be mainly influenced by environmental factors, such as lifestyle, but also genetics may play a role. The interaction of gut microbiota and obesity has been widely studied, but in regard to non-alcoholic fatty liver disease (NAFLD) as a manifestation of obesity and insulin resistance, the causal role of the gut microbiome has not been fully established. The mechanisms by which the gut microbiome influences lipid accumulation, inflammatory responses, and occurrence of fibrosis in the liver are a topic of active research. In addition, the influence of exercise on gut microbiome composition is also being investigated. In clinical trials, exercise reduced hepatic steatosis independently of weight reduction. Other studies indicate that exercise may modulate the gut microbiome. This puts forward the question whether exercise could mediate its beneficial effects on NAFLD via changes in gut microbiome. Yet, the specific mechanisms underlying this potential connection are largely unknown. Thus, associative evidence from clinical trials, as well as mechanistic studies in vivo are called for to elucidate the relationship between exercise and the gut microbiome in NAFLD. Here, we review the current literature on exercise and the gut microbiome in NAFLD.
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Affiliation(s)
- Veera Houttu
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
- Department of Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
| | - Ulrika Boulund
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
- Department of Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
| | - Aldo Grefhorst
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
| | - Maarten R. Soeters
- Department of Endocrinology and Metabolism, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands
| | - Sara-Joan Pinto-Sietsma
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
- Department of Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
| | - Max Nieuwdorp
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
- Department of Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
| | - Adriaan G. Holleboom
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
- Department of Vascular Medicine, Amsterdam UMC, Location AMC at University of Amsterdam, Amsterdam, The Netherlands
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254
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Zhao Y, Jiang Q. Roles of the Polyphenol-Gut Microbiota Interaction in Alleviating Colitis and Preventing Colitis-Associated Colorectal Cancer. Adv Nutr 2020; 12:546-565. [PMID: 32905583 PMCID: PMC8009754 DOI: 10.1093/advances/nmaa104] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/07/2020] [Accepted: 07/29/2020] [Indexed: 12/17/2022] Open
Abstract
Accumulating evidence indicates that the gut microbiota can promote or inhibit colonic inflammation and carcinogenesis. Promotion of beneficial gut bacteria is considered a promising strategy to alleviate colonic diseases including colitis and colorectal cancer. Interestingly, dietary polyphenols, which have been shown to attenuate colitis and inhibit colorectal cancer in animal models and some human studies, appear to reach relatively high concentrations in the large intestine and to interact with the gut microbial community. This review summarizes the modulatory effects of polyphenols on the gut microbiota in humans and animals under healthy and diseased conditions including colitis and colitis-associated colorectal cancer (CAC). Existing human and animal studies indicate that polyphenols and polyphenol-rich whole foods are capable of elevating butyrate producers and probiotics that alleviate colitis and inhibit CAC, such as Lactobacillus and Bifidobacterium. Studies in colitis and CAC models indicate that polyphenols decrease opportunistic pathogenic or proinflammatory microbes and counteract disease-induced dysbiosis. Consistently, polyphenols also change microbial functions, including increasing butyrate formation. Moreover, polyphenol metabolites produced by the gut microbiota appear to have anticancer and anti-inflammatory activities, protect gut barrier integrity, and mitigate inflammatory conditions in cells and animal models. Based on these results, we conclude that polyphenol-mediated alteration of microbial composition and functions, together with polyphenol metabolites produced by the gut microbiota, likely contribute to the protective effects of polyphenols on colitis and CAC. Future research is needed to validate the causal role of the polyphenol-gut microbiota interaction in polyphenols' anti-colitis and anti-CAC effects, and to further elucidate mechanisms underlying such interaction.
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Affiliation(s)
- Yiying Zhao
- Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
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255
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Kreuzer M, Hardt WD. How Food Affects Colonization Resistance Against Enteropathogenic Bacteria. Annu Rev Microbiol 2020; 74:787-813. [DOI: 10.1146/annurev-micro-020420-013457] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Food has a major impact on all aspects of health. Recent data suggest that food composition can also affect susceptibility to infections by enteropathogenic bacteria. Here, we discuss how food may alter the microbiota as well as mucosal defenses and how this can affect infection. Salmonella Typhimurium diarrhea serves as a paradigm, and complementary evidence comes from other pathogens. We discuss the effects of food composition on colonization resistance, host defenses, and the infection process as well as the merits and limitations of mouse models and experimental foods, which are available to decipher the underlying mechanisms.
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Affiliation(s)
- Markus Kreuzer
- Institute of Microbiology, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Wolf-Dietrich Hardt
- Institute of Microbiology, Department of Biology, ETH Zurich, CH-8093 Zurich, Switzerland
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256
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Cahana I, Iraqi FA. Impact of host genetics on gut microbiome: Take-home lessons from human and mouse studies. Animal Model Exp Med 2020; 3:229-236. [PMID: 33024944 PMCID: PMC7529332 DOI: 10.1002/ame2.12134] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/23/2020] [Accepted: 08/23/2020] [Indexed: 12/19/2022] Open
Abstract
The intestinal microbiome has emerged as an important component involved in various diseases. Therefore, the interest in understanding the factors shaping its composition is growing. The gut microbiome, often defined as a complex trait, contains diverse components and its properties are determined by a combination of external and internal effects. Although much effort has been invested so far, it is still difficult to evaluate the extent to which human genetics shape the composition of the gut microbiota. However, in mouse studies, where the environmental factors are better controlled, the effect of the genetic background was significant. The purpose of this paper is to provide a current assessment of the role of human host genetics in shaping the gut microbiome composition. Despite the inconsistency of the reported results, it can be estimated that the genetic factor affects a portion of the microbiome. However, this effect is currently lower than the initial estimates, and it is difficult to separate the genetic influence from the environmental effect. Additionally, despite the differences between the microbial composition of humans and mice, results from mouse models can strengthen our knowledge of host genetics underlying the human gut microbial variation.
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Affiliation(s)
- Inbal Cahana
- Department of Human Microbiology and ImmunologySackler Faculty of MedicineTel‐Aviv UniversityTel‐AvivIsrael
| | - Fuad A. Iraqi
- Department of Human Microbiology and ImmunologySackler Faculty of MedicineTel‐Aviv UniversityTel‐AvivIsrael
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257
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Yoshida N, Saito Y, Tsujimoto Y, Taito S, Banno M, Kataoka Y, Yamashita T, Hirata KI. The impact of antibiotics on the metabolic status of obese adults without bacterial infection: a systematic review and meta-analysis. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1059. [PMID: 33145278 PMCID: PMC7575975 DOI: 10.21037/atm-20-1007a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 07/18/2020] [Indexed: 01/13/2023]
Abstract
BACKGROUND The gut microbiota is involved in the pathophysiology of obesity. It is known that oral antibiotics manipulate the gut microbiota; however, the impact on host metabolism of obese adults without bacterial infection has not been systematically summarized. METHODS We searched for randomized, placebo-controlled trials that investigated the effects of oral antibiotics on the metabolic status in obese adults via Medline, EMBASE, and the Cochrane Library. Primary outcomes were homeostasis model assessment of insulin resistance (HOMA-IR), body weight, and rate of diarrhea. Additional outcomes included fasting plasma glucose (FPG), plasma glucagon-like peptide-1 (GLP-1), waist circumference, fecal short-chain fatty acid (SCFA) levels, and all adverse events. We assessed the certainty of evidence based on Grading of Recommendations, Assessment, Development and Evaluations. RESULTS Among 1,762 articles screened, four studies were eligible for quantitative analysis, two of which were applied to meta-analysis. Oral antibiotics had low influence on HOMA-IR [mean difference (MD) 0.09 (95% CI: -0.96 to 1.13)], body weight [MD 4.1 kg (95% CI: -23.77 to 31.97)], FPG [MD -0.12 mmol/L (95% CI: -0.47 to 0.23)], and GLP-1 [MD 0.20 pmol/L (95% CI: -2.36 to 2.76)] compared to placebo. Antibiotics treatment altered fecal acetate and butyrate levels, but resulted in little difference in propionate levels [MD -13.60 µmol/g (95% CI: -22.43 to -4.77), MD -7.60 µmol/g (-10.97 to -4.23), MD -1.10 µmol/g (95% CI: -4.18 to 1.98), respectively]. Several adverse events, such as sun sensitivity and gastrointestinal discomfort, were reported following antibiotics treatment, but no diarrhea. The certainty of evidence for most outcomes was very low to low, except for fecal SCFAs. CONCLUSIONS Our results indicate that oral antibiotics treatment is insufficient to ameliorate metabolic parameters in obese adults, suggesting that oral antibiotics treatment may not qualify as a therapeutic approach for obesity.
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Affiliation(s)
- Naofumi Yoshida
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
- Systematic Review Workshop Peer Support Group (SRWS-PSG), Japan
| | - Yoshihiro Saito
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yasushi Tsujimoto
- Systematic Review Workshop Peer Support Group (SRWS-PSG), Japan
- Department of Nephrology and Dialysis, Kyoritsu Hospital, Kawanishi, Japan
- Healthcare Epidemiology, School of Public Health in the Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shunsuke Taito
- Systematic Review Workshop Peer Support Group (SRWS-PSG), Japan
- Division of Rehabilitation, Department of Clinical Practice and Support, Hiroshima University Hospital, Hiroshima, Japan
| | - Masahiro Banno
- Systematic Review Workshop Peer Support Group (SRWS-PSG), Japan
- Department of Psychiatry, Seichiryo Hospital, Nagoya, Japan
- Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuki Kataoka
- Systematic Review Workshop Peer Support Group (SRWS-PSG), Japan
- Hospital Care Research Unit, Hyogo Prefectural Amagasaki General Medical Center, Amagasaki, Japan
| | - Tomoya Yamashita
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ken-ichi Hirata
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
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258
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Park JC, Im SH. Of men in mice: the development and application of a humanized gnotobiotic mouse model for microbiome therapeutics. Exp Mol Med 2020; 52:1383-1396. [PMID: 32908211 PMCID: PMC8080820 DOI: 10.1038/s12276-020-0473-2] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 06/08/2020] [Accepted: 06/16/2020] [Indexed: 12/11/2022] Open
Abstract
Considerable evidence points to the critical role of the gut microbiota in physiology and disease. The administration of live microbes as a therapeutic modality is increasingly being considered. However, key questions such as how to identify candidate microorganisms and which preclinical models are relevant to recapitulate human microbiota remain largely unanswered. The establishment of a humanized gnotobiotic mouse model through the fecal microbiota transplantation of human feces into germ-free mice provides an innovative and powerful tool to mimic the human microbial system. However, numerous considerations are required in designing such a model, as various elements, ranging from the factors pertaining to human donors to the mouse genetic background, affect how microbes colonize the gut. Thus, it is critical to match the murine context to that of human donors to provide a continuous and faithful progression of human flora in mice. This is of even greater importance when the need for accuracy and reproducibility across global research groups are taken into account. Here, we review the key factors that affect the formulation of a humanized mouse model representative of the human gut flora and propose several approaches as to how researchers can effectively design such models for clinical relevance.
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Affiliation(s)
- John Chulhoon Park
- Department of Life Sciences, Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Sin-Hyeog Im
- Department of Life Sciences, Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Gyeongbuk, 37673, Republic of Korea.
- ImmunoBiome Inc. POSTECH Biotech Center, Pohang, 37673, Republic of Korea.
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259
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Teng G, Liu Y, Wu T, Wang W, Wang H, Hu F. Efficacy of Sucralfate-Combined Quadruple Therapy on Gastric Mucosal Injury Induced by Helicobacter pylori and Its Effect on Gastrointestinal Flora. BIOMED RESEARCH INTERNATIONAL 2020; 2020:4936318. [PMID: 32934960 PMCID: PMC7479470 DOI: 10.1155/2020/4936318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 07/15/2020] [Accepted: 07/30/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND This study explored the therapeutic efficacy of standard triple therapy combined with sucralfate suspension gel as well as the mechanisms of action in mouse models of H. pylori infection. MATERIALS AND METHODS C57BL/6J mice were randomly divided into 5 groups: NC (natural control), HP (H. pylori infection), RAC (rabeprazole, amoxicillin, and clarithromycin), RACS (RAC and sucralfate suspension gel), and RACB (RAC and bismuth potassium citrate). HE staining and electron microscopy were performed to estimate histological and ultrastructural damages. The IL-8, IL-10, and TNF-α of gastric antrum tissues were measured by immunohistochemistry and qRT-PCR. ZO-1 and Occludin were also detected with immunohistochemistry. The genomes of gastric and fecal microbiota were sequenced. RESULTS The eradication rate of H. pylori in the RACS group was higher than the RAC group. RACS therapy had protective effects on H. pylori-induced histological and ultrastructural damages, which were superior to the RAC group. RACS therapy reduced the protein and mRNA levels of IL-8 compared with the RAC group. The expression of Occludin in the RACS group was significantly higher than that of the RAC group. The composition of gastric and fecal microbiota for RACS was similar to the RACB group according to PCA. CONCLUSIONS The RACS regimen eradicated H. pylori infection effectively and showed RACS had protective effects against H. pylori-induced histological and ultrastructural damage. The mechanisms of RACS effects included decreasing IL-8, enhancing Occludin, and transforming gastric microbiota. Moreover, RACS and RACB have a similar effect on gastrointestinal flora.
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Affiliation(s)
- Guigen Teng
- Departments of Gastroenterology, Peking University First Hospital, Beijing, China
| | - Yun Liu
- Department of Gastroenterology, Peking University People's Hospital, Beijing, China
| | - Ting Wu
- Departments of Gastroenterology, Peking University First Hospital, Beijing, China
| | - Weihong Wang
- Departments of Gastroenterology, Peking University First Hospital, Beijing, China
| | - Huahong Wang
- Departments of Gastroenterology, Peking University First Hospital, Beijing, China
| | - Fulian Hu
- Departments of Gastroenterology, Peking University First Hospital, Beijing, China
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260
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Emmert H, Rademacher F, Gläser R, Harder J. Skin microbiota analysis in human 3D skin models-"Free your mice". Exp Dermatol 2020; 29:1133-1139. [PMID: 32748435 DOI: 10.1111/exd.14164] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/08/2020] [Accepted: 07/17/2020] [Indexed: 12/22/2022]
Abstract
In the May issue of Experimental Dermatology 2018, we published a review article focusing on human 3D skin models in the context of microbiota research. The principal intention was to provide an overview of present and future concepts to use skin models in microbiota analyses. With the present viewpoint, we would like to draw the reader's attention again to the use of human skin models in microbiota research with the aim to highlight the benefits and necessity of human skin models to analyse the human skin-microbiota interaction. This is accompanied by a critical view on mice models that often are not suitable to analyse the functional impact of the human skin microbiota. In addition, we present novel and future concepts highlighting the benefits of human 3D skin models in microbiota research.
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Affiliation(s)
- Hila Emmert
- Department of Dermatology, Kiel University, Kiel, Germany
| | | | - Regine Gläser
- Department of Dermatology, Kiel University, Kiel, Germany
| | - Jürgen Harder
- Department of Dermatology, Kiel University, Kiel, Germany
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261
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Can the Cecal Ligation and Puncture Model Be Repurposed To Better Inform Therapy in Human Sepsis? Infect Immun 2020; 88:IAI.00942-19. [PMID: 32571986 DOI: 10.1128/iai.00942-19] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A recent report by the National Institutes of Health on sepsis research has implied there is a trend to move away from mouse models of sepsis. The most commonly used animal model to study the pathogenesis of human sepsis is cecal ligation and puncture (CLP) in mice. The model has been the mainstay of sepsis research for decades and continues to be considered the gold standard to inform novel pathways of sepsis physiology and its therapeutic direction. As there have been many criticisms of the model, particularly regarding its relevance to human disease, how this model might be repurposed to be more reflective of the human condition begs discussion. In this piece, we compare and contrast the mouse microbiome of the CLP model to the emerging science of the microbiome of human sepsis and discuss the relevance for mice to harbor the specific pathogens present in the human microbiome during sepsis, as well as an underlying disease process to mimic the characteristics of those patients with undesirable outcomes. How to repurpose this model to incorporate these "human factors" is discussed in detail and suggestions offered.
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262
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Kreft L, Hoffmann C, Ohnmacht C. Therapeutic Potential of the Intestinal Microbiota for Immunomodulation of Food Allergies. Front Immunol 2020; 11:1853. [PMID: 32922400 PMCID: PMC7456891 DOI: 10.3389/fimmu.2020.01853] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 07/09/2020] [Indexed: 12/19/2022] Open
Abstract
Food allergy is an atopic disease that is caused by the immune system targeting harmless food antigens that can result in life-threatening anaphylaxis. As humans and microbes have co-evolved, inevitably commensal microbes have a tremendous impact on our health. As such, the gut with its enormous microbial richness reflects a highly tolerogenic environment at steady state, in which immune cells are educated to react in a well-calibrated manner to food and microbial antigens. Recent evidence indicates that the susceptibility to food allergy is critically linked to microbial dysbiosis and can be transmitted by microbial transfer from humans to mice. Experimental work and epidemiological studies further point toward a critical time window in early childhood during which the immune system is imprinted by microbial colonization. Particularly, Foxp3-expressing regulatory T cells turn out to be key players, acting as rheostats for controlling the magnitude of food allergic reactions. An increasing number of bacterial metabolites has recently been shown to regulate directly or indirectly the differentiation of peripherally induced Tregs, most of which co-express the RAR-related orphan receptor gamma t (RORγt). Genetic ablation provided additional direct evidence for the importance of RORγt+ Tregs in food allergy. Future strategies for the stratification of food allergic patients with the aim to manipulate the intestinal microbiota by means of fecal transplantation efforts, pre- or probiotic regimens or for boosting oral immunotherapy may improve diagnosis and therapy. In this review some of the key underlying mechanisms are summarized and future directions for potential microbial therapy are explored.
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Affiliation(s)
- Luisa Kreft
- Mucosal Immunology Group, Center of Allery and Environment (ZAUM), Technical University and Helmholtz Center Munich, Munich, Germany.,Member of the German Center of Lung Research (DZL), Munich, Germany
| | - Christian Hoffmann
- Mucosal Immunology Group, Center of Allery and Environment (ZAUM), Technical University and Helmholtz Center Munich, Munich, Germany.,Member of the German Center of Lung Research (DZL), Munich, Germany.,Department of Food Science and Experimental Nutrition, Food Research Center (FoRC), School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Caspar Ohnmacht
- Mucosal Immunology Group, Center of Allery and Environment (ZAUM), Technical University and Helmholtz Center Munich, Munich, Germany.,Member of the German Center of Lung Research (DZL), Munich, Germany
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263
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Zorraquín I, Sánchez-Hernández E, Ayuda-Durán B, Silva M, González-Paramás AM, Santos-Buelga C, Moreno-Arribas MV, Bartolomé B. Current and future experimental approaches in the study of grape and wine polyphenols interacting gut microbiota. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2020; 100:3789-3802. [PMID: 32167171 DOI: 10.1002/jsfa.10378] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/02/2020] [Accepted: 03/13/2020] [Indexed: 06/10/2023]
Abstract
Interactions between polyphenols and gut microbiota are indeed a major issue of current interest in food science research. Knowledge in this subject is progressing as the experimental procedures and analysis techniques do. The aim of this article is to critically review the more leading-edge approaches that have been applied so far in the study of the interactions between grape/wine polyphenols and gut microbiota. This is the case of in vitro dynamic gastrointestinal simulation models that try to mitigate the limitations of simple static models (batch culture fermentations). More complex approaches include the experimentation with animals (mice, rats, pigs, lambs and chicks) and nutritional intervention studies in humans. Main advantages and limitations as well as the most relevant findings achieved by each approach in the study of how grape/wine polyphenols can modulate the composition and/or functionality of gut microbiota, are detailed. Also, common findings obtained by the three approaches (in vitro, animal models and human nutritional interventions) such as the fact that the Firmicutes/Bacteroidetes ratio tends to decrease after the feed/intake/consumption of grape/wine polyphenols are highlighted. Additionally, a nematode (Caenorhabditis elegans) model, previously used for investigating the mechanisms of processes such as aging, neurodegeneration, oxidative stress and inflammation, is presented as an emerging approach for the study of polyphenols interacting gut microbiota. © 2020 Society of Chemical Industry.
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Affiliation(s)
| | | | - Begoña Ayuda-Durán
- Grupo de Investigación en Polifenoles, Universidad de Salamanca, Salamanca, Spain
| | - Mariana Silva
- Institute of Food Science Research (CIAL), Madrid, Spain
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264
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Schrenk D, Bignami M, Bodin L, Chipman JK, del Mazo J, Hogstrand C, Hoogenboom L(R, Leblanc J, Nebbia CS, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T, Vleminckx C, Wallace H, Brimer L, Cottrill B, Dusemund B, Mulder P, Vollmer G, Binaglia M, Ramos Bordajandi L, Riolo F, Roldán‐Torres R, Grasl‐Kraupp B. Risk assessment of glycoalkaloids in feed and food, in particular in potatoes and potato-derived products. EFSA J 2020; 18:e06222. [PMID: 32788943 PMCID: PMC7417869 DOI: 10.2903/j.efsa.2020.6222] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of glycoalkaloids (GAs) in feed and food. This risk assessment covers edible parts of potato plants and other food plants containing GAs, in particular, tomato and aubergine. In humans, acute toxic effects of potato GAs (α-solanine and α-chaconine) include gastrointestinal symptoms such as nausea, vomiting and diarrhoea. For these effects, the CONTAM Panel identified a lowest-observed-adverse-effect level of 1 mg total potato GAs/kg body weight (bw) per day as a reference point for the risk characterisation following acute exposure. In humans, no evidence of health problems associated with repeated or long-term intake of GAs via potatoes has been identified. No reference point for chronic exposure could be identified from the experimental animal studies. Occurrence data were available only for α-solanine and α-chaconine, mostly for potatoes. The acute dietary exposure to potato GAs was estimated using a probabilistic approach and applying processing factors for food. Due to the limited data available, a margin of exposure (MOE) approach was applied. The MOEs for the younger age groups indicate a health concern for the food consumption surveys with the highest mean exposure, as well as for the P95 exposure in all surveys. For adult age groups, the MOEs indicate a health concern only for the food consumption surveys with the highest P95 exposures. For tomato and aubergine GAs, the risk to human health could not be characterised due to the lack of occurrence data and the limited toxicity data. For horses, farm and companion animals, no risk characterisation for potato GAs could be performed due to insufficient data on occurrence in feed and on potential adverse effects of GAs in these species.
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Mercer KE, Ten Have GAM, Pack L, Lan R, Deutz NEP, Adams SH, Piccolo BD. Net release and uptake of xenometabolites across intestinal, hepatic, muscle, and renal tissue beds in healthy conscious pigs. Am J Physiol Gastrointest Liver Physiol 2020; 319:G133-G141. [PMID: 32538141 PMCID: PMC7500263 DOI: 10.1152/ajpgi.00153.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Xenometabolites from microbial and plant sources are thought to confer beneficial as well as deleterious effects on host physiology. Studies determining absorption and tissue uptake of xenometabolites are limited. We utilized a conscious catheterized pig model to evaluate interorgan flux of annotated known and suspected xenometabolites, derivatives, and bile acids. Female pigs (n = 12, 2-3 mo old, 25.6 ± 2.2 kg) had surgically implanted catheters across portal-drained viscera (PDV), splanchnic compartment (SPL), liver, kidney, and hindquarter muscle. Overnight-fasted arterial and venous plasma was collected simultaneously in a conscious state and stored at -80°C. Thawed samples were analyzed by liquid chromatography-mass spectrometry. Plasma flow was determined with para-aminohippuric acid dilution technology and used to calculate net organ balance for each metabolite. Significant organ uptake or release was determined if net balance differed from zero. A total of 48 metabolites were identified in plasma, and 31 of these had at least one tissue with a significant net release or uptake. All bile acids, indole-3-acetic acid, indole-3-arylic acid, and hydrocinnamic acid were released from the intestine and taken up by the liver. Indole-3-carboxaldehyde, p-cresol glucuronide, 4-hydroxyphenyllactic acid, dodecanendioic acid, and phenylacetylglycine were also released from the intestines. Liver or kidney uptake was noted for indole-3-acetylglycine, p-cresol glucuronide, atrolactic acid, and dodecanedioic acid. Indole-3-carboxaldehyde, atrolactic acid, and dodecanedioic acids showed net release from skeletal muscle. The results confirm gastrointestinal origins for several known xenometabolites in an in vivo overnight-fasted conscious pig model, whereas nongut net release of other putative xenometabolites suggests a more complex metabolism.NEW & NOTEWORTHY Xenometabolites from microbe origins influence host health and disease, but absorption and tissue uptake of these metabolites remain speculative. Results herein are the first to demonstrate in vivo organ uptake and release of these metabolites. We used a conscious catheterized pig model to confirm gastrointestinal origins for several xenometabolites (e.g., indolic compounds, 4-hydroxyphenyllactic acid, dodecanendioic acid, and phenylacetylgycine). Liver and kidney were major sites for xenometabolite uptake, likely highlighting liver conjugation metabolism and renal excretion.
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Affiliation(s)
- Kelly E. Mercer
- 1Arkansas Children’s Nutrition Center, Little Rock, Arkansas,2Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Gabriella A. M. Ten Have
- 3Center for Translational Research in Aging and Longevity, Department of Health and Kinesiology, Texas A & M University, College Station, Texas
| | - Lindsay Pack
- 1Arkansas Children’s Nutrition Center, Little Rock, Arkansas
| | - Renny Lan
- 1Arkansas Children’s Nutrition Center, Little Rock, Arkansas,2Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Nicolaas E. P. Deutz
- 3Center for Translational Research in Aging and Longevity, Department of Health and Kinesiology, Texas A & M University, College Station, Texas
| | - Sean H. Adams
- 1Arkansas Children’s Nutrition Center, Little Rock, Arkansas,2Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Brian D. Piccolo
- 1Arkansas Children’s Nutrition Center, Little Rock, Arkansas,2Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
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266
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Kakni P, Hueber R, Knoops K, López‐Iglesias C, Truckenmüller R, Habibovic P, Giselbrecht S. Intestinal Organoid Culture in Polymer Film‐Based Microwell Arrays. ACTA ACUST UNITED AC 2020; 4:e2000126. [DOI: 10.1002/adbi.202000126] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/12/2020] [Indexed: 12/16/2022]
Affiliation(s)
- Panagiota Kakni
- Department of Instructive Biomaterials Engineering MERLN Institute for Technology‐Inspired Regenerative Medicine Maastricht University Universiteitssingel 40 Maastricht ER 6229 The Netherlands
| | - Rui Hueber
- Department of Instructive Biomaterials Engineering MERLN Institute for Technology‐Inspired Regenerative Medicine Maastricht University Universiteitssingel 40 Maastricht ER 6229 The Netherlands
| | - Kèvin Knoops
- Microscopy CORE Lab Maastricht Multimodal Molecular Imaging Institute (M4I) Maastricht University Universiteitssingel 50 Maastricht ER 6229 The Netherlands
| | - Carmen López‐Iglesias
- Microscopy CORE Lab Maastricht Multimodal Molecular Imaging Institute (M4I) Maastricht University Universiteitssingel 50 Maastricht ER 6229 The Netherlands
| | - Roman Truckenmüller
- Department of Instructive Biomaterials Engineering MERLN Institute for Technology‐Inspired Regenerative Medicine Maastricht University Universiteitssingel 40 Maastricht ER 6229 The Netherlands
| | - Pamela Habibovic
- Department of Instructive Biomaterials Engineering MERLN Institute for Technology‐Inspired Regenerative Medicine Maastricht University Universiteitssingel 40 Maastricht ER 6229 The Netherlands
| | - Stefan Giselbrecht
- Department of Instructive Biomaterials Engineering MERLN Institute for Technology‐Inspired Regenerative Medicine Maastricht University Universiteitssingel 40 Maastricht ER 6229 The Netherlands
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267
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Piñeiro SA, Cerniglia CE. Antimicrobial drug residues in animal-derived foods: Potential impact on the human intestinal microbiome. J Vet Pharmacol Ther 2020; 44:215-222. [PMID: 32710465 DOI: 10.1111/jvp.12892] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 06/17/2020] [Accepted: 06/29/2020] [Indexed: 12/23/2022]
Abstract
The use of veterinary drugs in food-producing animals may result in the presence of low levels of drug residues in these edible, animal-derived foods, with potential dietary exposure to humans. Since therapeutic doses of antibiotics have been shown to affect bacterial populations in the gastrointestinal tract microbiome and can also promote the emergence of antibiotic-resistant bacteria, there is concern that animal drugs at residue level concentrations could also perturb the intestinal microbiome composition and modify the antimicrobial resistance profile of the human intestinal microbiota. This review provides updated information on the VICH GL#36(R2), on evaluating the safety of veterinary drug residues in animal-derived foods and their effects on the human intestinal microbiome; discusses critical research knowledge gaps and challenges in evaluating the impact of drug residues in animal-derived foods on the human intestinal microbiome; and analyzes integrated basic and applied research approaches, currently being conducted at FDA, on studies that specifically address key regulatory science questions. Moreover, this review aims to emphasize future research needs on scientific methodology and provides general recommendations on drug inactivation, bioavailability, and antimicrobial resistance, to improve the safety evaluation and risk assessment of antimicrobial residues and their impact on the gastrointestinal microbiota, with the goal of ensuring food safety.
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Affiliation(s)
- Silvia Aurora Piñeiro
- Division of Human Food Safety, Center for Veterinary Medicine, U.S. Food and Drug Administration, Rockville, MD, USA
| | - Carl Edward Cerniglia
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, USA
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268
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Squarzanti DF, Zavattaro E, Pizzimenti S, Amoruso A, Savoia P, Azzimonti B. Non-Melanoma Skin Cancer: news from microbiota research. Crit Rev Microbiol 2020; 46:433-449. [PMID: 32692305 DOI: 10.1080/1040841x.2020.1794792] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Recently, research has been deeply focusing on the role of the microbiota in numerous diseases, either affecting the skin or other organs. What it is well established is that its dysregulation promotes several cutaneous disorders (i.e. psoriasis and atopic dermatitis). To date, little is known about its composition, mediators and role in the genesis, progression and response to therapy of Non-Melanoma Skin Cancer (NMSC). Starting from a bibliographic study, we classified the selected articles into four sections: i) normal skin microbiota; ii) in vitro study models; iii) microbiota and NMSC and iv) probiotics, antibiotics and NMSC. What has emerged is how skin microflora changes, mainly represented by increases of Staphylococcus aureus, Streptococcus pyogenes and Pseudomonas aeruginosa strains, modifications in the mutual quantity of β-Human papillomavirus genotypes, of Epstein Barr Virus and Malassezia or candidiasis, may contribute to the induction of a state of chronic self-maintaining inflammation, leading to cancer. In this context, the role of S. aureus and that of specific antimicrobial peptides look to be prominent. Moreover, although antibiotics may contribute to carcinogenesis, due to their ability to influence the microbiota balance, specific probiotics, such as Lacticaseibacillus rhamnosus GG, Lactobacillus johnsonii NCC 533 and Bifidobacteria spp., may be protective.
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Affiliation(s)
- Diletta Francesca Squarzanti
- Department of Health Sciences (DiSS), University of Piemonte Orientale (UPO), Novara, Italy.,Center for Translational Research on Autoimmune and Allergic Diseases (CAAD), DiSS, UPO, Novara, Italy
| | - Elisa Zavattaro
- Department of Translational Medicine (DiMeT), UPO, Novara, Italy
| | - Stefania Pizzimenti
- Department of Clinical and Biological Sciences (DSCB), University of Turin, Turin, Italy
| | | | - Paola Savoia
- Department of Health Sciences (DiSS), University of Piemonte Orientale (UPO), Novara, Italy
| | - Barbara Azzimonti
- Department of Health Sciences (DiSS), University of Piemonte Orientale (UPO), Novara, Italy.,Center for Translational Research on Autoimmune and Allergic Diseases (CAAD), DiSS, UPO, Novara, Italy
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269
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Huang Z, Pan Z, Yang R, Bi Y, Xiong X. The canine gastrointestinal microbiota: early studies and research frontiers. Gut Microbes 2020; 11:635-654. [PMID: 31992112 PMCID: PMC7524387 DOI: 10.1080/19490976.2019.1704142] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The canine gut microbiota is a complex microbial population that is potentially related to metabolism, immunologic activity and gastrointestinal (GI) diseases. Early studies revealed that the canine gut microbiota was dynamic, and bacterial populations in the adjacent gut segments were similar, with anaerobes predominating. Metagenomics analysis revealed that nutrient contents in the diet modulated bacterial populations and metabolites in the canine gut. Further research revealed significant correlations between dietary factors and canine gut core microbiomes. Canine GI diseases are closely correlated with gut microbiota dysbiosis and metabolic disorders. Probiotic-related therapies can effectively treat canine GI diseases. Recent studies have revealed that the canine gut microbiota is similar to the human gut microbiota, and dietary factors affect both. Studying canine intestinal microorganisms enables clarifying changes in the canine intestinal bacteria under different conditions, simulating human diseases in dog models, and conducting in-depth studies of the interactions between intestinal bacteria and disease.
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Affiliation(s)
- Zongyu Huang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China,State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Zhiyuan Pan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Ruifu Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yujing Bi
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China,CONTACT Yujing Bi State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Xiaohui Xiong
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China,Xiaohui Xiong Nanjing Tech University, Nanjing, China
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270
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Johnson D, Letchumanan V, Thurairajasingam S, Lee LH. A Revolutionizing Approach to Autism Spectrum Disorder Using the Microbiome. Nutrients 2020; 12:E1983. [PMID: 32635373 PMCID: PMC7400420 DOI: 10.3390/nu12071983] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/30/2020] [Accepted: 06/30/2020] [Indexed: 02/07/2023] Open
Abstract
The study of human microbiota and health has emerged as one of the ubiquitous research pursuits in recent decades which certainly warrants the attention of both researchers and clinicians. Many health conditions have been linked to the gut microbiota which is the largest reservoir of microbes in the human body. Autism spectrum disorder (ASD) is one of the neurodevelopmental disorders which has been extensively explored in relation to gut microbiome. The utilization of microbial knowledge promises a more integrative perspective in understanding this disorder, albeit being an emerging field in research. More interestingly, oral and vaginal microbiomes, indicating possible maternal influence, have equally drawn the attention of researchers to study their potential roles in the etiopathology of ASD. Therefore, this review attempts to integrate the knowledge of microbiome and its significance in relation to ASD including the hypothetical aetiology of ASD and its commonly associated comorbidities. The microbiota-based interventions including diet, prebiotics, probiotics, antibiotics, and faecal microbial transplant (FMT) have also been explored in relation to ASD. Of these, diet and probiotics are seemingly promising breakthrough interventions in the context of ASD for lesser known side effects, feasibility and easier administration, although more studies are needed to ascertain the actual clinical efficacy of these interventions. The existing knowledge and research gaps call for a more expanded and resolute research efforts in establishing the relationship between autism and microbiomes.
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Affiliation(s)
- Dinyadarshini Johnson
- Novel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway 47500, Malaysia; (D.J.); (V.L.)
| | - Vengadesh Letchumanan
- Novel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway 47500, Malaysia; (D.J.); (V.L.)
| | - Sivakumar Thurairajasingam
- Clinical School Johor Bahru, Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Johor Bahru 80100, Malaysia;
| | - Learn-Han Lee
- Novel Bacteria and Drug Discovery Research Group (NBDD), Microbiome and Bioresource Research Strength (MBRS), Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway 47500, Malaysia; (D.J.); (V.L.)
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271
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A direct comparison of mouse and human intestinal development using epithelial gene expression patterns. Pediatr Res 2020; 88:66-76. [PMID: 31242501 PMCID: PMC6930976 DOI: 10.1038/s41390-019-0472-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/12/2019] [Accepted: 06/08/2019] [Indexed: 11/20/2022]
Abstract
BACKGROUND Preterm infants are susceptible to unique pathology due to their immaturity. Mouse models are commonly used to study immature intestinal disease, including necrotizing enterocolitis (NEC). Current NEC models are performed at a variety of ages, but data directly comparing intestinal developmental stage equivalency between mice and humans are lacking. METHODS Small intestines were harvested from C57BL/6 mice at 3-4 days intervals from birth to P28 (n = 8 at each age). Preterm human small intestine samples representing 17-23 weeks of completed gestation were obtained from the University of Pittsburgh Health Sciences Tissue Bank, and at term gestation during reanastamoses after resection for NEC (n = 4-7 at each age). Quantification of intestinal epithelial cell types and messenger RNA for marker genes were evaluated on both species. RESULTS Overall, murine and human developmental trends over time are markedly similar. Murine intestine prior to P10 is most similar to human fetal intestine prior to viability. Murine intestine at P14 is most similar to human intestine at 22-23 weeks completed gestation, and P28 murine intestine is most similar to human term intestine. CONCLUSION Use of C57BL/6J mice to model the human immature intestine is reasonable, but the age of mouse chosen is a critical factor in model development.
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272
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Gibson PR, Halmos EP, Muir JG. Review article: FODMAPS, prebiotics and gut health-the FODMAP hypothesis revisited. Aliment Pharmacol Ther 2020; 52:233-246. [PMID: 32562590 DOI: 10.1111/apt.15818] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/27/2020] [Accepted: 05/07/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Restriction of dietary FODMAP intake can alleviate symptoms in patients with irritable bowel syndrome. Because many FODMAPs have prebiotic actions, there is concern that their dietary restriction leads to dysbiosis with health consequences, and their intake is being encouraged by addition to foods and via supplements. AIMS To examine the hazards and benefits of high and low FODMAP intake. METHODS Current literature was reviewed and alternative hypotheses formulated. RESULTS Low FODMAP intake reduces abundance of faecal Bifidobacteria without known adverse outcomes and has no effect on diversity, but the reduction in bacterial density may potentially be beneficial to gut health. Supplementary prebiotics can markedly elevate the intake of FODMAPs over levels consumed in the background diet. While this increases the abundance of Bifidobacteria, it adversely affects gut health in animal studies by inducing colonic mucosal barrier dysfunction, mucosal inflammation and visceral hypersensitivity. Rapid colonic fermentation is central to the identified mechanisms that include injury from high luminal concentrations of short-chain fatty acids and low pH, and inflammatory effects of increased endotoxin load and glycation of macromolecules. Whether these observations translate into humans requires further study. Opposing hypotheses are presented whereby excessive intake of FODMAPs might have health benefits via prebiotic effects, but might also be injurious and contribute to the apparent increase in functional intestinal disorders. CONCLUSIONS Reduced FODMAP intake has few deleterious effects on gut microbiota. Consequences (both positive and negative) of excessive carbohydrate fermentation in the human intestines from elevated FODMAP intake require more attention.
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Affiliation(s)
- Peter R Gibson
- Department of Gastroenterology, Monash University and Alfred Health, Melbourne, Vic., Australia
| | - Emma P Halmos
- Department of Gastroenterology, Monash University and Alfred Health, Melbourne, Vic., Australia
| | - Jane G Muir
- Department of Gastroenterology, Monash University and Alfred Health, Melbourne, Vic., Australia
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273
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Sutherland VL, McQueen CA, Mendrick D, Gulezian D, Cerniglia C, Foley S, Forry S, Khare S, Liang X, Manautou JE, Tweedie D, Young H, Alekseyenko AV, Burns F, Dietert R, Wilson A, Chen C. The Gut Microbiome and Xenobiotics: Identifying Knowledge Gaps. Toxicol Sci 2020; 176:1-10. [PMID: 32658296 PMCID: PMC7850111 DOI: 10.1093/toxsci/kfaa060] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
There is an increasing awareness that the gut microbiome plays a critical role in human health and disease, but mechanistic insights are often lacking. In June 2018, the Health and Environmental Sciences Institute (HESI) held a workshop, "The Gut Microbiome: Markers of Human Health, Drug Efficacy and Xenobiotic Toxicity" (https://hesiglobal.org/event/the-gut-microbiome-workshop) to identify data gaps in determining how gut microbiome alterations may affect human health. Speakers and stakeholders from academia, government, and industry addressed multiple topics including the current science on the gut microbiome, endogenous and exogenous metabolites, biomarkers, and model systems. The workshop presentations and breakout group discussions formed the basis for identifying data gaps and research needs. Two critical issues that emerged were defining the microbial composition and function related to health and developing standards for models, methods and analysis in order to increase the ability to compare and replicate studies. A series of key recommendations were formulated to focus efforts to further understand host-microbiome interactions and the consequences of exposure to xenobiotics as well as identifying biomarkers of microbiome-associated disease and toxicity.
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Affiliation(s)
- Vicki L Sutherland
- National Toxicology Program, National Institute of Environmental Health Sciences, Durham, North Carolina 27709
| | - Charlene A McQueen
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona 85721
| | - Donna Mendrick
- National Center for Toxicological Research, US Food and Drug Administration, Silver Spring, MD 20993
| | | | - Carl Cerniglia
- Department of Pharmacokinetics, Pharmacodynamics and Drug Metabolism, Merck & Co., Inc., Kenilworth, New Jersey 07033
| | - Steven Foley
- Department of Pharmacokinetics, Pharmacodynamics and Drug Metabolism, Merck & Co., Inc., Kenilworth, New Jersey 07033
| | - Sam Forry
- Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899
| | - Sangeeta Khare
- National Center for Toxicological Research, US Food and Drug Administration, Silver Spring, MD 20993
| | - Xue Liang
- Merck Exploratory Science Center, Merck & Co., Inc., Cambridge, Massachusetts 02141
| | - Jose E Manautou
- Department of Pharmaceutics, University of Connecticut, Storrs, Connecticut 06269
| | - Donald Tweedie
- Department of Pharmacokinetics, Pharmacodynamics and Drug Metabolism, Merck & Co., Inc., Kenilworth, New Jersey 07033
| | - Howard Young
- Laboratory of Cancer Immunometabolism, Center for Cancer Research, NCI Frederick, Frederick, Maryland 21702
| | - Alexander V Alekseyenko
- Program for Human Microbiome Research, Biomedical Informatics Center, Department of Public Health Sciences, Department of Oral Health Sciences, Department of Healthcare Leadership & Management, Medical University of South Carolina, Charleston, South Carolina 29425
| | | | - Rod Dietert
- Department of Microbiology and Immunology, Cornell University, Ithaca, New York 14850
| | - Alan Wilson
- Department of Drug Metabolism, Pharmacokinetics, Toxicology and Pathology, Lexicon Pharmaceuticals, Houston, Texas 77381
| | - Connie Chen
- Health and Environmental Sciences Institute, Washington, District of Columbia 20005
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274
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Cassotta M, Forbes-Hernández TY, Calderón Iglesias R, Ruiz R, Elexpuru Zabaleta M, Giampieri F, Battino M. Links between Nutrition, Infectious Diseases, and Microbiota: Emerging Technologies and Opportunities for Human-Focused Research. Nutrients 2020; 12:E1827. [PMID: 32575399 PMCID: PMC7353391 DOI: 10.3390/nu12061827] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 02/06/2023] Open
Abstract
The interaction between nutrition and human infectious diseases has always been recognized. With the emergence of molecular tools and post-genomics, high-resolution sequencing technologies, the gut microbiota has been emerging as a key moderator in the complex interplay between nutrients, human body, and infections. Much of the host-microbial and nutrition research is currently based on animals or simplistic in vitro models. Although traditional in vivo and in vitro models have helped to develop mechanistic hypotheses and assess the causality of the host-microbiota interactions, they often fail to faithfully recapitulate the complexity of the human nutrient-microbiome axis in gastrointestinal homeostasis and infections. Over the last decade, remarkable progress in tissue engineering, stem cell biology, microfluidics, sequencing technologies, and computing power has taken place, which has produced a new generation of human-focused, relevant, and predictive tools. These tools, which include patient-derived organoids, organs-on-a-chip, computational analyses, and models, together with multi-omics readouts, represent novel and exciting equipment to advance the research into microbiota, infectious diseases, and nutrition from a human-biology-based perspective. After considering some limitations of the conventional in vivo and in vitro approaches, in this review, we present the main novel available and emerging tools that are suitable for designing human-oriented research.
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Affiliation(s)
- Manuela Cassotta
- Centre for Nutrition and Health, Universidad Europea del Atlántico (UEA), 39001 Santander, Spain; (M.C.); (R.C.I.); (R.R.)
| | - Tamara Yuliett Forbes-Hernández
- Department of Analytical and Food Chemistry, Nutrition and Food Science Group, CITACA, CACTI, University of Vigo, 36310 Vigo, Spain;
| | - Ruben Calderón Iglesias
- Centre for Nutrition and Health, Universidad Europea del Atlántico (UEA), 39001 Santander, Spain; (M.C.); (R.C.I.); (R.R.)
| | - Roberto Ruiz
- Centre for Nutrition and Health, Universidad Europea del Atlántico (UEA), 39001 Santander, Spain; (M.C.); (R.C.I.); (R.R.)
| | - Maria Elexpuru Zabaleta
- Dipartimento di Scienze Cliniche e Molecolari, Facoltà di Medicina, Università Politecnica delle Marche, 60131 Ancona, Italy;
| | - Francesca Giampieri
- Department of Analytical and Food Chemistry, Nutrition and Food Science Group, CITACA, CACTI, University of Vigo, 36310 Vigo, Spain;
- Department of Clinical Sciences, Faculty of Medicine, Polytechnic University of Marche, 60131 Ancona, Italy
- College of Food Science and Technology, Northwest University, Xi’an 710069, China
| | - Maurizio Battino
- Department of Analytical and Food Chemistry, Nutrition and Food Science Group, CITACA, CACTI, University of Vigo, 36310 Vigo, Spain;
- Department of Clinical Sciences, Faculty of Medicine, Polytechnic University of Marche, 60131 Ancona, Italy
- International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
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Dávalos-Salas M, Mariadason JM, Watt MJ, Montgomery MK. Molecular regulators of lipid metabolism in the intestine - Underestimated therapeutic targets for obesity? Biochem Pharmacol 2020; 178:114091. [PMID: 32535104 DOI: 10.1016/j.bcp.2020.114091] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 02/07/2023]
Abstract
The incidence of obesity and type 2 diabetes continues to rise across the globe necessitating the need to identify new therapeutic approaches to manage these diseases. In this review, we explore the potential for therapeutic interventions focussed on the intestinal epithelium, by targeting the role of this tissue in lipid uptake, lipid-mediated cross talk and lipid oxidation. We focus initially on ongoing strategies to manage obesity by targeting the essential role of the intestinal epithelium in lipid uptake, and in mediating tissue cross talk to regulate food intake. Subsequently, we explore a previously underestimated capacity of intestinal epithelial cells to oxidize fatty acids. In this context, we describe recent findings which have unveiled a key role for the peroxisome proliferator-activated receptor (PPAR) family of nuclear receptors and histone deacetylases (HDACs) in the regulation of lipid oxidation genes in enterocytes and how targeted genetic manipulation of these factors in enterocytes reduces weight gain, identifying intestinal PPARs and HDACs as potential therapeutic targets in the management of obesity.
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Affiliation(s)
- Mercedes Dávalos-Salas
- Olivia Newton John Cancer Research Institute, Melbourne, Victoria, Australia; La Trobe University School of Cancer Medicine, Melbourne, Victoria, Australia
| | - John M Mariadason
- Olivia Newton John Cancer Research Institute, Melbourne, Victoria, Australia; La Trobe University School of Cancer Medicine, Melbourne, Victoria, Australia
| | - Matthew J Watt
- Department of Physiology, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Magdalene K Montgomery
- Department of Physiology, Faculty of Medicine Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia.
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276
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Berlemont R, Winans N, Talamantes D, Dang H, Tsai HW. MetaGeneHunt for protein domain annotation in short-read metagenomes. Sci Rep 2020; 10:7712. [PMID: 32382098 PMCID: PMC7205989 DOI: 10.1038/s41598-020-63775-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/03/2020] [Indexed: 12/13/2022] Open
Abstract
The annotation of short-reads metagenomes is an essential process to understand the functional potential of sequenced microbial communities. Annotation techniques based solely on the identification of local matches tend to confound local sequence similarity and overall protein homology and thus don't mirror the complex multidomain architecture and the shuffling of functional domains in many protein families. Here, we present MetaGeneHunt to identify specific protein domains and to normalize the hit-counts based on the domain length. We used MetaGeneHunt to investigate the potential for carbohydrate processing in the mouse gastrointestinal tract. We sampled, sequenced, and analyzed the microbial communities associated with the bolus in the stomach, intestine, cecum, and colon of five captive mice. Focusing on Glycoside Hydrolases (GHs) we found that, across samples, 58.3% of the 4,726,023 short-read sequences matching with a GH domain-containing protein were located outside the domain of interest. Next, before comparing the samples, the counts of localized hits matching the domains of interest were normalized to account for the corresponding domain length. Microbial communities in the intestine and cecum displayed characteristic GH profiles matching distinct microbial assemblages. Conversely, the stomach and colon were associated with structurally and functionally more diverse and variable microbial communities. Across samples, despite fluctuations, changes in the functional potential for carbohydrate processing correlated with changes in community composition. Overall MetaGeneHunt is a new way to quickly and precisely identify discrete protein domains in sequenced metagenomes processed with MG-RAST. In addition, using the sister program "GeneHunt" to create custom Reference Annotation Table, MetaGeneHunt provides an unprecedented way to (re)investigate the precise distribution of any protein domain in short-reads metagenomes.
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Affiliation(s)
- R Berlemont
- Department of biological Sciences, California State University, Long Beach, California, USA.
| | - N Winans
- Department of biological Sciences, California State University, Long Beach, California, USA
| | - D Talamantes
- Department of biological Sciences, California State University, Long Beach, California, USA
- Department of Bioinformatics, University of Georgia Athens, Athens, Georgia, USA
| | - H Dang
- Department of biological Sciences, California State University, Long Beach, California, USA
| | - H-W Tsai
- Department of biological Sciences, California State University, Long Beach, California, USA
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277
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Li B, Chen H, Cao L, Hu Y, Chen D, Yin Y. Effects of an Escherichia coli exopolysaccharide on human and mouse gut microbiota in vitro. Int J Biol Macromol 2020; 150:991-999. [DOI: 10.1016/j.ijbiomac.2019.10.186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 10/10/2019] [Accepted: 10/21/2019] [Indexed: 12/16/2022]
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278
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Wade KH, Hall LJ. Improving causality in microbiome research: can human genetic epidemiology help? Wellcome Open Res 2020; 4:199. [PMID: 32462081 PMCID: PMC7217228 DOI: 10.12688/wellcomeopenres.15628.3] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2020] [Indexed: 12/13/2022] Open
Abstract
Evidence supports associations between human gut microbiome variation and multiple health outcomes and diseases. Despite compelling results from in vivo and in vitro models, few findings have been translated into an understanding of modifiable causal relationships. Furthermore, epidemiological studies have been unconvincing in their ability to offer causal evidence due to their observational nature, where confounding by lifestyle and behavioural factors, reverse causation and bias are important limitations. Whilst randomized controlled trials have made steps towards understanding the causal role played by the gut microbiome in disease, they are expensive and time-consuming. This evidence that has not been translated between model systems impedes opportunities for harnessing the gut microbiome for improving population health. Therefore, there is a need for alternative approaches to interrogate causality in the context of gut microbiome research. The integration of human genetics within population health sciences have proved successful in facilitating improved causal inference (e.g., with Mendelian randomization [MR] studies) and characterising inherited disease susceptibility. MR is an established method that employs human genetic variation as natural "proxies" for clinically relevant (and ideally modifiable) traits to improve causality in observational associations between those traits and health outcomes. Here, we focus and discuss the utility of MR within the context of human gut microbiome research, review studies that have used this method and consider the strengths, limitations and challenges facing this research. Specifically, we highlight the requirements for careful examination and interpretation of derived causal estimates and host (i.e., human) genetic effects themselves, triangulation across multiple study designs and inter-disciplinary collaborations. Meeting these requirements will help support or challenge causality of the role played by the gut microbiome on human health to develop new, targeted therapies to alleviate disease symptoms to ultimately improve lives and promote good health.
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Affiliation(s)
- Kaitlin H. Wade
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, BS8 2BN, UK
| | - Lindsay J. Hall
- Gut Microbes & Health, Quadram Institute Bioscience, Norwich, NR4 7UQ, UK
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279
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Kaur H, Nagamoto-Combs K, Golovko S, Golovko MY, Klug MG, Combs CK. Probiotics ameliorate intestinal pathophysiology in a mouse model of Alzheimer's disease. Neurobiol Aging 2020; 92:114-134. [PMID: 32417748 DOI: 10.1016/j.neurobiolaging.2020.04.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 02/06/2023]
Abstract
Evidence suggests that changes in intestinal microbiota may affect the central nervous system. However, it is unclear whether alteration of intestinal microbiota affects progression of Alzheimer's disease (AD). To understand this, wild-type control (C57BL/6) mice were compared with the AppNL-G-F model of disease. We used probiotic supplementation to manipulate the gut microbiota. Fecal samples were collected for microbiota profiling. To study brain and intestinal inflammation, biochemical and histological analyses were performed. Altered metabolic pathways were examined by quantifying eicosanoid and bile acid profiles in the brain and serum using ultraperformance liquid chromatography-tandem mass spectrometry. We observed that brain pathology was associated with intestinal dysbiosis and increased intestinal inflammation and leakiness in AppNL-G-F mice. Probiotic supplementation significantly decreased intestinal inflammation and gut permeability with minimal effect on amyloid-β, cytokine, or gliosis levels in the brain. Concentrations of several bile acids and prostaglandins were altered in the serum and brain because of AD or probiotic supplementation. Our study characterizes intestinal dysfunction in an AD mouse model and the potential of probiotic intervention to ameliorate this condition.
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Affiliation(s)
- Harpreet Kaur
- Department of Biomedical Sciences, University of North Dakota, School of Medicine & Health Sciences, Grand Forks, ND, USA
| | - Kumi Nagamoto-Combs
- Department of Pathology, University of North Dakota, School of Medicine & Health Sciences, Grand Forks, ND, USA
| | - Svetlana Golovko
- Department of Biomedical Sciences, University of North Dakota, School of Medicine & Health Sciences, Grand Forks, ND, USA
| | - Mikhail Y Golovko
- Department of Biomedical Sciences, University of North Dakota, School of Medicine & Health Sciences, Grand Forks, ND, USA
| | - Marilyn G Klug
- Department of Population Health, University of North Dakota, School of Medicine & Health Sciences, Grand Forks, ND, USA
| | - Colin Kelly Combs
- Department of Biomedical Sciences, University of North Dakota, School of Medicine & Health Sciences, Grand Forks, ND, USA.
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280
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Animal models of mucositis: critical tools for advancing pathobiological understanding and identifying therapeutic targets. Curr Opin Support Palliat Care 2020; 13:119-133. [PMID: 30925531 DOI: 10.1097/spc.0000000000000421] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Mucositis remains a prevalent, yet poorly managed side effect of anticancer therapies. Mucositis affecting both the oral cavity and gastrointestinal tract predispose to infection and require extensive supportive management, contributing to the growing economic burden associated with cancer care. Animal models remain a critical aspect of mucositis research, providing novel insights into its pathogenesis and revealing therapeutic targets. The current review aims to provide a comprehensive overview of the current animal models used in mucositis research. RECENT FINDINGS A wide variety of animal models of mucositis exist highlighting the highly heterogenous landscape of supportive oncology and the unique cytotoxic mechanisms of different anticancer agents. Golden Syrian hamsters remain the gold-standard species for investigation of oral mucositis induced by single dose and fractionated radiation as well as chemoradiation. There is no universally accepted gold-standard model for the study of gastrointestinal mucositis, with rats, mice, pigs and dogs all offering unique perspectives on its pathobiology. SUMMARY Animal models are a critical aspect of mucositis research, providing unprecedent insight into the pathobiology of mucositis. Introduction of tumour-bearing models, cyclic dosing scheduled, concomitant agents and genetically modified animals have been integral in refining our understanding of mucositis.
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281
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Wade KH, Hall LJ. Improving causality in microbiome research: can human genetic epidemiology help? Wellcome Open Res 2020; 4:199. [PMID: 32462081 PMCID: PMC7217228 DOI: 10.12688/wellcomeopenres.15628.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2020] [Indexed: 03/29/2024] Open
Abstract
Evidence supports associations between human gut microbiome variation and multiple health outcomes and diseases. Despite compelling results from in vivo and in vitro models, few findings have been translated into an understanding of modifiable causal relationships. Furthermore, epidemiological studies have been unconvincing in their ability to offer causal evidence due to their observational nature, where confounding by lifestyle and behavioural factors, reverse causation and bias are important limitations. Whilst randomized controlled trials have made steps towards understanding the causal role played by the gut microbiome in disease, they are expensive and time-consuming. This evidence that has not been translated between model systems impedes opportunities for harnessing the gut microbiome for improving population health. Therefore, there is a need for alternative approaches to interrogate causality in the context of gut microbiome research. The integration of human genetics within population health sciences have proved successful in facilitating improved causal inference (e.g., with Mendelian randomization [MR] studies) and characterising inherited disease susceptibility. MR is an established method that employs human genetic variation as natural "proxies" for clinically relevant (and ideally modifiable) traits to improve causality in observational associations between those traits and health outcomes. Here, we focus and discuss the utility of MR within the context of human gut microbiome research, review studies that have used this method and consider the strengths, limitations and challenges facing this research. Specifically, we highlight the requirements for careful examination and interpretation of derived causal estimates and host (i.e., human) genetic effects themselves, triangulation across multiple study designs and inter-disciplinary collaborations. Meeting these requirements will help support or challenge causality of the role played by the gut microbiome on human health to develop new, targeted therapies to alleviate disease symptoms to ultimately improve lives and promote good health.
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Affiliation(s)
- Kaitlin H. Wade
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, BS8 2BN, UK
| | - Lindsay J. Hall
- Gut Microbes & Health, Quadram Institute Bioscience, Norwich, NR4 7UQ, UK
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282
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Simpson CA, Mu A, Haslam N, Schwartz OS, Simmons JG. Feeling down? A systematic review of the gut microbiota in anxiety/depression and irritable bowel syndrome. J Affect Disord 2020; 266:429-446. [PMID: 32056910 DOI: 10.1016/j.jad.2020.01.124] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 12/24/2019] [Accepted: 01/20/2020] [Indexed: 12/18/2022]
Abstract
Background Anxiety/depression and irritable bowel syndrome (IBS) are highly prevalent and burdensome conditions, whose co-occurrence is estimated between 44 and 84%. Shared gut microbiota alterations have been identified in these separate disorders relative to controls; however, studies have not adequately considered their comorbidity. This review set out to identify case-control studies comparing the gut microbiota in anxiety/depression, IBS, and both conditions comorbidly relative to each other and to controls, as well as gut microbiota investigations including measures of both IBS and anxiety/depression. Methods Four databases were systematically searched using comprehensive search terms (OVID Medline, Embase, PsycINFO, and PubMed), following PRISMA guidelines. Results Systematic review identified 17 studies (10 human, 7 animal). Most studies investigated the gut microbiota and anxiety/depression symptoms in IBS cohorts. Participants with IBS and high anxiety/depression symptoms had lower alpha diversity compared to controls and IBS-only cohorts. Machine learning and beta diversity distinguished between IBS participants with and without anxiety/depression by their gut microbiota. Comorbid IBS and anxiety/depression also had higher abundance of Proteobacteria, Prevotella/Prevotellaceae, Bacteroides and lower Lachnospiraceae relative to controls. Limitations A large number of gut microbiota estimation methods and statistical techniques were utilized; therefore, meta-analysis was not possible. Conclusions Well-designed case-control and longitudinal studies are required to disentangle whether the gut microbiota is predicted as a continuum of gastrointestinal and anxiety/depression symptom severity, or whether reported dysbiosis is unique to IBS and anxiety/depression comorbidity. These findings may inform the development of targeted treatment through the gut microbiota for individuals with both anxiety/depression and IBS.
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Affiliation(s)
- Carra A Simpson
- Melbourne School of Psychological Sciences, The University of Melbourne, 12th floor Redmond Barry Building, Parkville, VIC, Australia; Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, VIC, Australia.
| | - Andre Mu
- Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, VIC, Australia; Doherty Applied Microbial Genomics, Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, VIC, Australia; Microbiological Diagnostic Unit Public Health Laboratory, at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, VIC, Australia
| | - Nick Haslam
- Melbourne School of Psychological Sciences, The University of Melbourne, 12th floor Redmond Barry Building, Parkville, VIC, Australia
| | - Orli S Schwartz
- Orygen, The National Centre of Excellence in Youth Mental Health; Centre for Youth Mental Health, The University of Melbourne, VIC, Australia
| | - Julian G Simmons
- Melbourne School of Psychological Sciences, The University of Melbourne, 12th floor Redmond Barry Building, Parkville, VIC, Australia; Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, VIC, Australia
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283
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Vendrik KEW, Ooijevaar RE, de Jong PRC, Laman JD, van Oosten BW, van Hilten JJ, Ducarmon QR, Keller JJ, Kuijper EJ, Contarino MF. Fecal Microbiota Transplantation in Neurological Disorders. Front Cell Infect Microbiol 2020; 10:98. [PMID: 32266160 PMCID: PMC7105733 DOI: 10.3389/fcimb.2020.00098] [Citation(s) in RCA: 209] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 02/26/2020] [Indexed: 12/14/2022] Open
Abstract
Background: Several studies suggested an important role of the gut microbiota in the pathophysiology of neurological disorders, implying that alteration of the gut microbiota might serve as a treatment strategy. Fecal microbiota transplantation (FMT) is currently the most effective gut microbiota intervention and an accepted treatment for recurrent Clostridioides difficile infections. To evaluate indications of FMT for patients with neurological disorders, we summarized the available literature on FMT. In addition, we provide suggestions for future directions. Methods: In July 2019, five main databases were searched for studies and case descriptions on FMT in neurological disorders in humans or animal models. In addition, the ClinicalTrials.gov website was consulted for registered planned and ongoing trials. Results: Of 541 identified studies, 34 were included in the analysis. Clinical trials with FMT have been performed in patients with autism spectrum disorder and showed beneficial effects on neurological symptoms. For multiple sclerosis and Parkinson's disease, several animal studies suggested a positive effect of FMT, supported by some human case reports. For epilepsy, Tourette syndrome, and diabetic neuropathy some studies suggested a beneficial effect of FMT, but evidence was restricted to case reports and limited numbers of animal studies. For stroke, Alzheimer's disease and Guillain-Barré syndrome only studies with animal models were identified. These studies suggested a potential beneficial effect of healthy donor FMT. In contrast, one study with an animal model for stroke showed increased mortality after FMT. For Guillain-Barré only one study was identified. Whether positive findings from animal studies can be confirmed in the treatment of human diseases awaits to be seen. Several trials with FMT as treatment for the above mentioned neurological disorders are planned or ongoing, as well as for amyotrophic lateral sclerosis. Conclusions: Preliminary literature suggests that FMT may be a promising treatment option for several neurological disorders. However, available evidence is still scanty and some contrasting results were observed. A limited number of studies in humans have been performed or are ongoing, while for some disorders only animal experiments have been conducted. Large double-blinded randomized controlled trials are needed to further elucidate the effect of FMT in neurological disorders.
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Affiliation(s)
- Karuna E W Vendrik
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands.,Netherlands Donor Feces Bank, Leiden University Medical Center, Leiden, Netherlands.,Centre for Infectious Disease Control, National Institute for Public Health and the Environment (Rijksinstituut voor Volksgezondheid en Milieu, RIVM), Bilthoven, Netherlands
| | - Rogier E Ooijevaar
- Netherlands Donor Feces Bank, Leiden University Medical Center, Leiden, Netherlands.,Department of Gastroenterology, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, Netherlands
| | - Pieter R C de Jong
- Department of Neurology, Leiden University Medical Center, Leiden, Netherlands
| | - Jon D Laman
- Department Biomedical Sciences of Cells & Systems, University Medical Center Groningen, Groningen, Netherlands
| | - Bob W van Oosten
- Department of Neurology, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, Netherlands
| | | | - Quinten R Ducarmon
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands.,Center for Microbiome Analyses and Therapeutics, Leiden University Medical Center, Leiden, Netherlands
| | - Josbert J Keller
- Netherlands Donor Feces Bank, Leiden University Medical Center, Leiden, Netherlands.,Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, Netherlands.,Department of Gastroenterology, Haaglanden Medical Center, The Hague, Netherlands
| | - Eduard J Kuijper
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands.,Netherlands Donor Feces Bank, Leiden University Medical Center, Leiden, Netherlands.,Centre for Infectious Disease Control, National Institute for Public Health and the Environment (Rijksinstituut voor Volksgezondheid en Milieu, RIVM), Bilthoven, Netherlands.,Center for Microbiome Analyses and Therapeutics, Leiden University Medical Center, Leiden, Netherlands
| | - Maria Fiorella Contarino
- Department of Neurology, Leiden University Medical Center, Leiden, Netherlands.,Department of Neurology, Haga Teaching Hospital, The Hague, Netherlands
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284
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Food matrix and the microbiome: considerations for preclinical chronic disease studies. Nutr Res 2020; 78:1-10. [PMID: 32247914 DOI: 10.1016/j.nutres.2020.02.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/05/2020] [Accepted: 02/25/2020] [Indexed: 01/05/2023]
Abstract
Animal models of chronic disease are continuously being refined and have evolved with the goal of increasing the translation of results to human populations. Examples of this progress include transgenic models and germ-free animals conventionalized with human microbiota. The gut microbiome is involved in the etiology of several chronic diseases. Therefore, consideration of the experimental conditions that may affect the gut microbiome in preclinical disease is very important. Of note, diet plays a large role in shaping the gut microbiome and can be a source of variation between animal models and human populations. Traditionally, nutrition researchers have focused on manipulating the macronutrient profile of experimental diets to model diseases such as metabolic syndrome. However, other dietary components found in human foods, but not in animal diets, can have sizable effects on the composition and metabolic capacity of the gut microbiome and, as a consequence, manifestation of the chronic disease being modeled. The purpose of this review is to describe how food matrix food components, including diverse fiber sources, oxidation products from cooking, and dietary fat emulsifiers, shape the composition of the gut microbiome and influence gut health.
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285
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Coleman CM, Ferreira D. Oligosaccharides and Complex Carbohydrates: A New Paradigm for Cranberry Bioactivity. Molecules 2020; 25:E881. [PMID: 32079271 PMCID: PMC7070526 DOI: 10.3390/molecules25040881] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 02/04/2020] [Accepted: 02/14/2020] [Indexed: 02/07/2023] Open
Abstract
Cranberry is a well-known functional food, but the compounds directly responsible for many of its reported health benefits remain unidentified. Complex carbohydrates, specifically xyloglucan and pectic oligosaccharides, are the newest recognized class of biologically active compounds identified in cranberry materials. Cranberry oligosaccharides have shown similar biological properties as other dietary oligosaccharides, including effects on bacterial adhesion, biofilm formation, and microbial growth. Immunomodulatory and anti-inflammatory activity has also been observed. Oligosaccharides may therefore be significant contributors to many of the health benefits associated with cranberry products. Soluble oligosaccharides are present at relatively high concentrations (~20% w/w or greater) in many cranberry materials, and yet their possible contributions to biological activity have remained unrecognized. This is partly due to the inherent difficulty of detecting these compounds without intentionally seeking them. Inconsistencies in product descriptions and terminology have led to additional confusion regarding cranberry product composition and the possible presence of oligosaccharides. This review will present our current understanding of cranberry oligosaccharides and will discuss their occurrence, structures, ADME, biological properties, and possible prebiotic effects for both gut and urinary tract microbiota. Our hope is that future investigators will consider these compounds as possible significant contributors to the observed biological effects of cranberry.
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Affiliation(s)
- Christina M. Coleman
- Department of BioMolecular Sciences, Division of Pharmacognosy, and the Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA
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286
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Bogatyrev SR, Rolando JC, Ismagilov RF. Self-reinoculation with fecal flora changes microbiota density and composition leading to an altered bile-acid profile in the mouse small intestine. MICROBIOME 2020; 8:19. [PMID: 32051033 PMCID: PMC7017497 DOI: 10.1186/s40168-020-0785-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 01/05/2020] [Indexed: 05/06/2023]
Abstract
BACKGROUND The upper gastrointestinal tract plays a prominent role in human physiology as the primary site for enzymatic digestion and nutrient absorption, immune sampling, and drug uptake. Alterations to the small intestine microbiome have been implicated in various human diseases, such as non-alcoholic steatohepatitis and inflammatory bowel conditions. Yet, the physiological and functional roles of the small intestine microbiota in humans remain poorly characterized because of the complexities associated with its sampling. Rodent models are used extensively in microbiome research and enable the spatial, temporal, compositional, and functional interrogation of the gastrointestinal microbiota and its effects on the host physiology and disease phenotype. Classical, culture-based studies have documented that fecal microbial self-reinoculation (via coprophagy) affects the composition and abundance of microbes in the murine proximal gastrointestinal tract. This pervasive self-reinoculation behavior could be a particularly relevant study factor when investigating small intestine microbiota. Modern microbiome studies either do not take self-reinoculation into account, or assume that approaches such as single housing mice or housing on wire mesh floors eliminate it. These assumptions have not been rigorously tested with modern tools. Here, we used quantitative 16S rRNA gene amplicon sequencing, quantitative microbial functional gene content inference, and metabolomic analyses of bile acids to evaluate the effects of self-reinoculation on microbial loads, composition, and function in the murine upper gastrointestinal tract. RESULTS In coprophagic mice, continuous self-exposure to the fecal flora had substantial quantitative and qualitative effects on the upper gastrointestinal microbiome. These differences in microbial abundance and community composition were associated with an altered profile of the small intestine bile acid pool, and, importantly, could not be inferred from analyzing large intestine or stool samples. Overall, the patterns observed in the small intestine of non-coprophagic mice (reduced total microbial load, low abundance of anaerobic microbiota, and bile acids predominantly in the conjugated form) resemble those typically seen in the human small intestine. CONCLUSIONS Future studies need to take self-reinoculation into account when using mouse models to evaluate gastrointestinal microbial colonization and function in relation to xenobiotic transformation and pharmacokinetics or in the context of physiological states and diseases linked to small intestine microbiome and to small intestine dysbiosis. Video abstract.
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Affiliation(s)
- Said R Bogatyrev
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Justin C Rolando
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, Pasadena, CA, USA
| | - Rustem F Ismagilov
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd, Pasadena, CA, USA.
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287
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O'Donovan AN, Herisson FM, Fouhy F, Ryan PM, Whelan D, Johnson CN, Cluzel G, Ross RP, Stanton C, Caplice NM. Gut microbiome of a porcine model of metabolic syndrome and HF-pEF. Am J Physiol Heart Circ Physiol 2020; 318:H590-H603. [PMID: 32031871 DOI: 10.1152/ajpheart.00512.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Metabolic syndrome (MetS) is a composite of cardiometabolic risk factors, including obesity, dyslipidemia, hypertension, and insulin resistance, with a range of secondary sequelae such as nonalcoholic fatty liver disease and diastolic heart failure. This syndrome has been identified as one of the greatest global health challenges of the 21st century. Herein, we examine whether a porcine model of diet- and mineralocorticoid-induced MetS closely mimics the cardiovascular, metabolic, gut microbiota, and functional metataxonomic phenotype observed in human studies. Landrace pigs with deoxycorticosterone acetate-induced hypertension fed a diet high in fat, salt, and sugar over 12 wk were assessed for hyperlipidemia, hyperinsulinemia, and immunohistologic, echocardiographic, and hemodynamic parameters, as well as assessed for microbiome phenotype and function through 16S rRNA metataxonomic and metabolomic analysis, respectively. All MetS animals developed obesity, hyperlipidemia, insulin resistance, hypertension, fatty liver, structural cardiovascular changes including left ventricular hypertrophy and left atrial enlargement, and increased circulating saturated fatty acid levels, all in keeping with the human phenotype. A reduction in α-diversity and specific microbiota changes at phylum, family, and genus levels were also observed in this model. Specifically, this porcine model of MetS displayed increased abundances of proinflammatory bacteria coupled with increased circulating tumor necrosis factor-α and increased secondary bile acid-producing bacteria, which substantially impacted fibroblast growth factor-19 expression. Finally, a significant decrease in enteroprotective bacteria and a reduction in short-chain fatty acid-producing bacteria were also noted. Together, these data suggest that diet and mineralocorticoid-mediated development of biochemical and cardiovascular stigmata of metabolic syndrome in pigs leads to temporal gut microbiome changes that mimic key gut microbial population signatures in human cardiometabolic disease.NEW & NOTEWORTHY This study extends a prior porcine model of cardiometabolic syndrome to include systemic inflammation, fatty liver, and insulin sensitivity. Gut microbiome changes during evolution of porcine cardiometabolic disease recapitulate those in human subjects with alterations in gut taxa associated with proinflammatory bacteria, bile acid, and fatty acid pathways. This clinical scale model may facilitate design of future interventional trials to test causal relationships between gut dysbiosis and cardiometabolic syndrome at a systemic and organ level.
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Affiliation(s)
- Aoife N O'Donovan
- Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.,School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Florence M Herisson
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Centre for Research in Vascular Biology, University College Cork, Cork, Ireland
| | - Fiona Fouhy
- Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.,APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Paul M Ryan
- Centre for Research in Vascular Biology, University College Cork, Cork, Ireland
| | - Derek Whelan
- Centre for Research in Vascular Biology, University College Cork, Cork, Ireland
| | - Crystal N Johnson
- Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.,APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Gaston Cluzel
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Centre for Research in Vascular Biology, University College Cork, Cork, Ireland
| | - R Paul Ross
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,College of Science, Engineering and Food Science, University College Cork, Cork, Ireland
| | - Catherine Stanton
- Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.,APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Noel M Caplice
- APC Microbiome Ireland, University College Cork, Cork, Ireland.,Centre for Research in Vascular Biology, University College Cork, Cork, Ireland
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288
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Scotti R, Southern S, Boinett C, Jenkins TP, Cortés A, Cantacessi C. MICHELINdb: a web-based tool for mining of helminth-microbiota interaction datasets, and a meta-analysis of current research. MICROBIOME 2020; 8:10. [PMID: 32008578 PMCID: PMC6996195 DOI: 10.1186/s40168-019-0782-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Accepted: 12/27/2019] [Indexed: 05/02/2023]
Abstract
BACKGROUND The complex network of interactions occurring between gastrointestinal (GI) and extra-intestinal (EI) parasitic helminths of humans and animals and the resident gut microbial flora is attracting increasing attention from biomedical researchers, because of the likely implications for the pathophysiology of helminth infection and disease. Nevertheless, the vast heterogeneity of study designs and microbial community profiling strategies, and of bioinformatic and biostatistical approaches for analyses of metagenomic sequence datasets hinder the identification of bacterial targets for follow-up experimental investigations of helminth-microbiota cross-talk. Furthermore, comparative analyses of published datasets are made difficult by the unavailability of a unique repository for metagenomic sequence data and associated metadata linked to studies aimed to explore potential changes in the composition of the vertebrate gut microbiota in response to GI and/or EI helminth infections. RESULTS Here, we undertake a meta-analysis of available metagenomic sequence data linked to published studies on helminth-microbiota cross-talk in humans and veterinary species using a single bioinformatic pipeline, and introduce the 'MICrobiome HELminth INteractions database' (MICHELINdb), an online resource for mining of published sequence datasets, and corresponding metadata, generated in these investigations. CONCLUSIONS By increasing data accessibility, we aim to provide the scientific community with a platform to identify gut microbial populations with potential roles in the pathophysiology of helminth disease and parasite-mediated suppression of host inflammatory responses, and facilitate the design of experiments aimed to disentangle the cause(s) and effect(s) of helminth-microbiota relationships. Video abstract.
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Affiliation(s)
- Riccardo Scotti
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK
- Present address: Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Stuart Southern
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK
| | - Christine Boinett
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK
| | - Timothy P Jenkins
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK
| | - Alba Cortés
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK
| | - Cinzia Cantacessi
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK.
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289
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Flux MC, Lowry CA. Finding intestinal fortitude: Integrating the microbiome into a holistic view of depression mechanisms, treatment, and resilience. Neurobiol Dis 2020; 135:104578. [PMID: 31454550 PMCID: PMC6995775 DOI: 10.1016/j.nbd.2019.104578] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 06/27/2019] [Accepted: 08/14/2019] [Indexed: 02/07/2023] Open
Abstract
Depression affects at least 322 million people globally, or approximately 4.4% of the world's population. While the earnestness of researchers and clinicians to understand and treat depression is not waning, the number of individuals suffering from depression continues to increase over and above the rate of global population growth. There is a sincere need for a paradigm shift. Research in the past decade is beginning to take a more holistic approach to understanding depression etiology and treatment, integrating multiple body systems into whole-body conceptualizations of this mental health affliction. Evidence supports the hypothesis that the gut microbiome, or the collective trillions of microbes inhabiting the gastrointestinal tract, is an important factor determining both the risk of development of depression and persistence of depressive symptoms. This review discusses recent advances in both rodent and human research that explore bidirectional communication between the gut microbiome and the immune, endocrine, and central nervous systems implicated in the etiology and pathophysiology of depression. Through interactions with circulating inflammatory markers and hormones, afferent and efferent neural systems, and other, more niche, pathways, the gut microbiome can affect behavior to facilitate the development of depression, exacerbate current symptoms, or contribute to treatment and resilience. While the challenge of depression may be the direst mental health crisis of our age, new discoveries in the gut microbiome, when integrated into a holistic perspective, hold great promise for the future of positive mental health.
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Affiliation(s)
- M C Flux
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO 80309, USA.
| | - Christopher A Lowry
- Department of Integrative Physiology, Center for Neuroscience, and Center for Microbial Exploration, University of Colorado Boulder, Boulder, CO 80309, USA; Department of Physical Medicine & Rehabilitation and Center for Neuroscience, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Veterans Health Administration, Rocky Mountain Mental Illness Research Education and Clinical Center (MIRECC), Rocky Mountain Regional Veterans Affairs Medical Center (RMRVAMC), Aurora, CO 80045, USA; Military and Veteran Microbiome: Consortium for Research and Education (MVM-CoRE), Aurora, CO 80045, USA; Senior Fellow, VIVO Planetary Health, Worldwide Universities Network (WUN), West New York, NJ 07093, USA.
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290
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Nakajima A, Habu S, Kasai M, Okumura K, Ishikawa D, Shibuya T, Kobayashi O, Osada T, Ohkusa T, Watanabe S, Nagahara A. Impact of maternal dietary gut microbial metabolites on an offspring's systemic immune response in mouse models. BIOSCIENCE OF MICROBIOTA FOOD AND HEALTH 2020; 39:33-38. [PMID: 32328398 PMCID: PMC7162694 DOI: 10.12938/bmfh.19-013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 12/31/2019] [Indexed: 12/12/2022]
Abstract
The gut microbiota has a great impact on the host immune systems. Recent evidence suggests that the maternal gut microbiota affects the immune systems of offspring. Metabolites produced by
the gut microbiota play crucial roles in the immune system. Previous studies have also revealed that metabolites such as short-chain fatty acids (SCFAs) and the aryl hydrocarbon receptor
(AhR) ligands are involved in host health and diseases. Great progress has been made in understanding the roles of diet-derived SCFAs in the offspring’s immune system. The findings to date
raise the possibility that maternal dietary soluble fiber intake may play a role in the development of the offspring’s systemic immune response. In this review, we summarize the present
knowledge and discuss future therapeutic possibilities for using dietary soluble fiber intake against inflammatory diseases.
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Affiliation(s)
- Akihito Nakajima
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Sonoko Habu
- Atopic Research Center, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Masataka Kasai
- Atopic Research Center, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Ko Okumura
- Atopic Research Center, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Dai Ishikawa
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Tomoyoshi Shibuya
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Osamu Kobayashi
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Taro Osada
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Toshifumi Ohkusa
- Department of Microbiota Research, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Sumio Watanabe
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Akihito Nagahara
- Department of Gastroenterology, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
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291
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Zhu S, Jiang Y, Xu K, Cui M, Ye W, Zhao G, Jin L, Chen X. The progress of gut microbiome research related to brain disorders. J Neuroinflammation 2020; 17:25. [PMID: 31952509 PMCID: PMC6969442 DOI: 10.1186/s12974-020-1705-z] [Citation(s) in RCA: 230] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/07/2020] [Indexed: 02/06/2023] Open
Abstract
There is increasing evidence showing that the dynamic changes in the gut microbiota can alter brain physiology and behavior. Cognition was originally thought to be regulated only by the central nervous system. However, it is now becoming clear that many non-nervous system factors, including the gut-resident bacteria of the gastrointestinal tract, regulate and influence cognitive dysfunction as well as the process of neurodegeneration and cerebrovascular diseases. Extrinsic and intrinsic factors including dietary habits can regulate the composition of the microbiota. Microbes release metabolites and microbiota-derived molecules to further trigger host-derived cytokines and inflammation in the central nervous system, which contribute greatly to the pathogenesis of host brain disorders such as pain, depression, anxiety, autism, Alzheimer’s diseases, Parkinson’s disease, and stroke. Change of blood–brain barrier permeability, brain vascular physiology, and brain structure are among the most critical causes of the development of downstream neurological dysfunction. In this review, we will discuss the following parts:
Overview of technical approaches used in gut microbiome studies Microbiota and immunity Gut microbiota and metabolites Microbiota-induced blood–brain barrier dysfunction Neuropsychiatric diseases
■ Stress and depression ■ Pain and migraine ■ Autism spectrum disorders
Neurodegenerative diseases
■ Parkinson’s disease ■ Alzheimer’s disease ■ Amyotrophic lateral sclerosis ■ Multiple sclerosis
Cerebrovascular disease
■ Atherosclerosis ■ Stroke ■ Arteriovenous malformation
Conclusions and perspectives
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Affiliation(s)
- Sibo Zhu
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Fudan University Taizhou Institute of Health Sciences, Taizhou, China.,Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Yanfeng Jiang
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Fudan University Taizhou Institute of Health Sciences, Taizhou, China
| | - Kelin Xu
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Fudan University Taizhou Institute of Health Sciences, Taizhou, China.,School of Data Science, Fudan University, Shanghai, China
| | - Mei Cui
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Weimin Ye
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Genming Zhao
- School of Data Science, Fudan University, Shanghai, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Fudan University Taizhou Institute of Health Sciences, Taizhou, China.,Human Phenome Institute, Fudan University, 825 Zhangheng Road, Shanghai, 201203, China
| | - Xingdong Chen
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China. .,Fudan University Taizhou Institute of Health Sciences, Taizhou, China. .,Human Phenome Institute, Fudan University, 825 Zhangheng Road, Shanghai, 201203, China.
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292
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Wu IW, Lin CY, Chang LC, Lee CC, Chiu CY, Hsu HJ, Sun CY, Chen YC, Kuo YL, Yang CW, Gao SS, Hsieh WP, Chung WH, Lai HC, Su SC. Gut Microbiota as Diagnostic Tools for Mirroring Disease Progression and Circulating Nephrotoxin Levels in Chronic Kidney Disease: Discovery and Validation Study. Int J Biol Sci 2020; 16:420-434. [PMID: 32015679 PMCID: PMC6990903 DOI: 10.7150/ijbs.37421] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 10/13/2019] [Indexed: 12/31/2022] Open
Abstract
The interplay of the gut microbes with gut-producing nephrotoxins and the renal progression remains unclear in large human cohort. Significant compositional and functional differences in the intestinal microbiota (by 16S rRNA gene sequencing) were noted among 30 controls and 92 (31 mild, 30 moderate and 31 advanced) patients at different chronic kidney disease (CKD) stages (discovery cohort). A core CKD-associated microbiota consisted of 7 genera (Escherichia_Shigella, Dialister, Lachnospiraceae_ND3007_group, Pseudobutyrivibrio, Roseburia, Paraprevotella and Ruminiclostridium) and 2 species (Collinsella stercoris and Bacteroides eggerthii) were identified to be highly correlated with the stages of CKD. Paraprevotella, Pseudobutyrivibrio and Collinsella stercoris were superior in discriminating CKD from the controls than the use of urine protein/creatinine ratio, even at early-stage of disease. The performance was further confirmed in a validation cohort comprising 22 controls and 76 peritoneal dialysis patients. Bacterial genera highly correlated with indoxyl sulfate and p-cresyl sulfate levels were identified. Prediction of the functional capabilities of microbial communities showed that microbial genes related to the metabolism of aromatic amino acids (phenylalanine, tyrosine, and tryptophan) were differentially enriched among the control and different CKD stages. Collectively, our results provide solid human evidence of the impact of gut-metabolite-kidney axis on the severity of chronic kidney disease and highlight a usefulness of specific gut microorganisms as possible disease differentiate marker of this global health burden.
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Affiliation(s)
- I-Wen Wu
- Department of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chan-Yu Lin
- College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Linkuo, Taiwan
| | - Lun-Ching Chang
- Department of Mathematical Sciences, Florida Atlantic University, Florida, US
| | - Chin-Chan Lee
- Department of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Chih-Yung Chiu
- Department of Pediatrics, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Heng-Jung Hsu
- Department of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Chiao-Yin Sun
- Department of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Yuen-Chan Chen
- Department of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Lun Kuo
- Biotools, Co., Ltd, New Taipei City, Taiwan
| | - Chi-Wei Yang
- College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Linkuo, Taiwan
| | - Sheng-Siang Gao
- Institute of Statistics, National Tsing-Hua University, Hsinchu, Taiwan
| | - Wen-Ping Hsieh
- Institute of Statistics, National Tsing-Hua University, Hsinchu, Taiwan
| | - Wen-Hung Chung
- Whole-Genome Research Core Laboratory of Human Diseases, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Hsin-Chih Lai
- Graduate Institute of Biomedical Sciences, Division of Biotechnology, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Microbiota Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Shih-Chi Su
- Whole-Genome Research Core Laboratory of Human Diseases, Chang Gung Memorial Hospital, Keelung, Taiwan
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293
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Jaggar M, Rea K, Spichak S, Dinan TG, Cryan JF. You've got male: Sex and the microbiota-gut-brain axis across the lifespan. Front Neuroendocrinol 2020; 56:100815. [PMID: 31805290 DOI: 10.1016/j.yfrne.2019.100815] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/16/2019] [Accepted: 11/11/2019] [Indexed: 02/07/2023]
Abstract
Sex is a critical factor in the diagnosis and development of a number of mental health disorders including autism, schizophrenia, depression, anxiety, Parkinson's disease, multiple sclerosis, anorexia nervosa and others; likely due to differences in sex steroid hormones and genetics. Recent evidence suggests that sex can also influence the complexity and diversity of microbes that we harbour in our gut; and reciprocally that our gut microbes can directly and indirectly influence sex steroid hormones and central gene activation. There is a growing emphasis on the role of gastrointestinal microbiota in the maintenance of mental health and their role in the pathogenesis of disease. In this review, we introduce mechanisms by which gastrointestinal microbiota are thought to mediate positive health benefits along the gut-brain axis, we report how they may be modulated by sex, the role they play in sex steroid hormone regulation, and their sex-specific effects in various disorders relating to mental health.
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Affiliation(s)
- Minal Jaggar
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Kieran Rea
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Simon Spichak
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Timothy G Dinan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.
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294
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Xiang Y, Wen H, Yu Y, Li M, Fu X, Huang S. Gut-on-chip: Recreating human intestine in vitro. J Tissue Eng 2020; 11:2041731420965318. [PMID: 33282173 PMCID: PMC7682210 DOI: 10.1177/2041731420965318] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 09/22/2020] [Indexed: 01/04/2023] Open
Abstract
The human gut is important for food digestion and absorption, as well as a venue for a large number of microorganisms that coexist with the host. Although numerous in vitro models have been proposed to study intestinal pathology or interactions between intestinal microbes and host, they are far from recapitulating the real intestinal microenvironment in vivo. To assist researchers in further understanding gut physiology, the intestinal microbiome, and disease processes, a novel technology primarily based on microfluidics and cell biology, called "gut-on-chip," was developed to simulate the structure, function, and microenvironment of the human gut. In this review, we first introduce various types of gut-on-chip systems, then highlight their applications in drug pharmacokinetics, host-gut microbiota crosstalk, and nutrition metabolism. Finally, we discuss challenges in this field and prospects for better understanding interactions between intestinal flora and human hosts, and then provide guidance for clinical treatment of related diseases.
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Affiliation(s)
- Yunqing Xiang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hui Wen
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Yue Yu
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Mingqiang Li
- Laboratory of Biomaterials and Translational Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiongfei Fu
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Shuqiang Huang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- University of Chinese Academy of Sciences, Beijing, China
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295
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Rutter JW, Ozdemir T, Galimov ER, Quintaneiro LM, Rosa L, Thomas GM, Cabreiro F, Barnes CP. Detecting Changes in the Caenorhabditis elegans Intestinal Environment Using an Engineered Bacterial Biosensor. ACS Synth Biol 2019; 8:2620-2628. [PMID: 31657907 PMCID: PMC6929061 DOI: 10.1021/acssynbio.9b00166] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Indexed: 12/12/2022]
Abstract
Caenorhabditis elegans has become a key model organism within biology. In particular, the transparent gut, rapid growing time, and ability to create a defined gut microbiota make it an ideal candidate organism for understanding and engineering the host microbiota. Here we present the development of an experimental model that can be used to characterize whole-cell bacterial biosensors in vivo. A dual-plasmid sensor system responding to isopropyl β-d-1-thiogalactopyranoside was developed and fully characterized in vitro. Subsequently, we show that the sensor was capable of detecting and reporting on changes in the intestinal environment of C. elegans after introducing an exogenous inducer into the environment. The protocols presented here may be used to aid the rational design of engineered bacterial circuits, primarily for diagnostic applications. In addition, the model system may serve to reduce the use of current animal models and aid in the exploration of complex questions within general nematode and host-microbe biology.
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Affiliation(s)
- Jack W. Rutter
- Department
of Cell and Developmental Biology, University
College London, London WC1E 6BT, United Kingdom
| | - Tanel Ozdemir
- Department
of Cell and Developmental Biology, University
College London, London WC1E 6BT, United Kingdom
| | - Evgeniy R. Galimov
- MRC
London Institute of Medical Sciences, London W12 0NN, United
Kingdom
| | - Leonor M. Quintaneiro
- Institute
of Structural and Molecular Biology, University
College London and Birkbeck College, London WC1E 6BT, United
Kingdom
| | - Luca Rosa
- Department
of Cell and Developmental Biology, University
College London, London WC1E 6BT, United Kingdom
| | - Geraint M. Thomas
- Department
of Cell and Developmental Biology, University
College London, London WC1E 6BT, United Kingdom
| | - Filipe Cabreiro
- MRC
London Institute of Medical Sciences, London W12 0NN, United
Kingdom
- Institute
of Structural and Molecular Biology, University
College London and Birkbeck College, London WC1E 6BT, United
Kingdom
| | - Chris P. Barnes
- Department
of Cell and Developmental Biology, University
College London, London WC1E 6BT, United Kingdom
- Department
of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
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296
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Wade KH, Hall LJ. Improving causality in microbiome research: can human genetic epidemiology help? Wellcome Open Res 2019; 4:199. [PMID: 32462081 PMCID: PMC7217228 DOI: 10.12688/wellcomeopenres.15628.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2019] [Indexed: 03/29/2024] Open
Abstract
Evidence supports associations between human gut microbiome variation and multiple health outcomes and diseases. Despite compelling results from in vivo and in vitro models, few findings have been translated into an understanding of modifiable causal relationships. Furthermore, epidemiological studies have been unconvincing in their ability to offer causal evidence due to their observational nature, where confounding by lifestyle and behavioural factors, reverse causation and bias are important limitations. Whilst randomized controlled trials have made steps towards understanding the causal role played by the gut microbiome in disease, they are expensive and time-consuming. This evidence that has not been translated between model systems impedes opportunities for harnessing the gut microbiome for improving population health. Therefore, there is a need for alternative approaches to interrogate causality in the context of gut microbiome research. The integration of human genetics within population health sciences have proved successful in facilitating improved causal inference (e.g., with Mendelian randomization [MR] studies) and characterising inherited disease susceptibility. MR is an established method that employs human genetic variation as natural "proxies" for clinically relevant (and ideally modifiable) traits to improve causality in observational associations between those traits and health outcomes. Here, we focus and discuss the utility of MR within the context of human gut microbiome research, review studies that have used this method and consider the strengths, limitations and challenges facing this research. Specifically, we highlight the requirements for careful examination and interpretation of derived causal estimates and host (i.e., human) genetic effects themselves, triangulation across multiple study designs and inter-disciplinary collaborations. Meeting these requirements will help support or challenge causality of the role played by the gut microbiome on human health to develop new, targeted therapies to alleviate disease symptoms to ultimately improve lives and promote good health.
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Affiliation(s)
- Kaitlin H. Wade
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
- Population Health Sciences, Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, BS8 2BN, UK
| | - Lindsay J. Hall
- Gut Microbes & Health, Quadram Institute Bioscience, Norwich, NR4 7UQ, UK
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297
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Shekhar S, Petersen FC, Yang X. Editorial: Understanding and Exploiting Host-Commensal Interactions to Combat Pathogens. Front Immunol 2019; 10:2645. [PMID: 31781125 PMCID: PMC6861415 DOI: 10.3389/fimmu.2019.02645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/25/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sudhanshu Shekhar
- Faculty of Dentistry, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | | | - Xi Yang
- Department of Immunology, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada
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298
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Mukherjee D, Chora ÂF, Mota MM. Microbiota, a Third Player in the Host-Plasmodium Affair. Trends Parasitol 2019; 36:11-18. [PMID: 31787522 DOI: 10.1016/j.pt.2019.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 11/01/2019] [Accepted: 11/01/2019] [Indexed: 12/14/2022]
Abstract
Plasmodium, the causative agent of malaria, is responsible for more than 200 million new infections and 400 000 deaths yearly. While in recent years the influence of the microbiota in homeostasis and a wide variety of disorders has taken center stage, its contribution during malaria infections has only now started to emerge. The few published studies suggest two distinct but complementary directions. Plasmodium infections can cause significant alterations in host (at least gut) microbiota, and host gut microbiota can influence the clinical outcome of malaria infections. In this opinion article, we highlight the most fundamental unanswered questions in the field that will, hopefully, point future research directions towards unveiling key mechanistic insights of the Plasmodium-host-microbiota axis.
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Affiliation(s)
- Debanjan Mukherjee
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal.
| | - Ângelo Ferreira Chora
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Maria M Mota
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal.
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299
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Potential Determinants of Gastrointestinal Dysfunction in Autism Spectrum Disorders. REVIEW JOURNAL OF AUTISM AND DEVELOPMENTAL DISORDERS 2019. [DOI: 10.1007/s40489-019-00187-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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300
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The Proton Pump Inhibitor Omeprazole Does Not Promote Clostridioides difficile Colonization in a Murine Model. mSphere 2019; 4:4/6/e00693-19. [PMID: 31748246 PMCID: PMC6887860 DOI: 10.1128/msphere.00693-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Antibiotics are the primary risk factor for Clostridioides difficile infections (CDIs), but other factors may also increase a person’s risk. In epidemiological studies, proton pump inhibitor (PPI) use has been associated with CDI incidence and recurrence. PPIs have also been associated with alterations in the human intestinal microbiota in observational and interventional studies. We evaluated the effects of the PPI omeprazole on the structure of the murine intestinal microbiota and its ability to disrupt colonization resistance to C. difficile. We found omeprazole treatment had minimal impact on the murine fecal microbiota and did not promote C. difficile colonization. Further studies are needed to determine whether other factors contribute to the association between PPIs and CDIs seen in humans or whether aspects of murine physiology may limit its utility to test these types of hypotheses. Proton pump inhibitor (PPI) use has been associated with microbiota alterations and susceptibility to Clostridioides difficile infections (CDIs) in humans. We assessed how PPI treatment alters the fecal microbiota and whether treatment promotes CDIs in a mouse model. Mice receiving a PPI treatment were gavaged with 40 mg of omeprazole per kg of body weight during a 7-day pretreatment phase, the day of C. difficile challenge, and the following 9 days. We found that mice treated with omeprazole were not colonized by C. difficile. When omeprazole treatment was combined with a single clindamycin treatment, one cage of mice remained resistant to C. difficile colonization, while the other cage was colonized. Treating mice with only clindamycin followed by challenge resulted in C. difficile colonization. 16S rRNA gene sequencing analysis revealed that omeprazole had minimal impact on the structure of the murine microbiota throughout the 16 days of omeprazole exposure. These results suggest that omeprazole treatment alone is not sufficient to disrupt microbiota resistance to C. difficile infection in mice that are normally resistant in the absence of antibiotic treatment. IMPORTANCE Antibiotics are the primary risk factor for Clostridioides difficile infections (CDIs), but other factors may also increase a person’s risk. In epidemiological studies, proton pump inhibitor (PPI) use has been associated with CDI incidence and recurrence. PPIs have also been associated with alterations in the human intestinal microbiota in observational and interventional studies. We evaluated the effects of the PPI omeprazole on the structure of the murine intestinal microbiota and its ability to disrupt colonization resistance to C. difficile. We found omeprazole treatment had minimal impact on the murine fecal microbiota and did not promote C. difficile colonization. Further studies are needed to determine whether other factors contribute to the association between PPIs and CDIs seen in humans or whether aspects of murine physiology may limit its utility to test these types of hypotheses.
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