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Abstract
Ankylosing spondylitis (AS), a chronic condition that commonly influences the spine and sacroiliac joints, usually progresses to stiffness and progressive functional limitation. Its fundamental etiology and pathogenesis are likely multifactorial and remain elusive. As environmental factors, gut microbiota performs critical functions in the pathogenesis of AS through various mechanisms, including interacting with genes, enhancing intestinal permeability, activating the gut mucosa immune system, and affecting the intestinal microbiota metabolites. This review provides an overview of recent advances in investigating gut microbiota in AS pathogenesis and discusses potential methods for future therapeutic intervention.
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Affiliation(s)
- Zi-Yi Song
- Department of Rheumatology, The Second Hospital of Shanxi Medical University, Taiyuan, China
- Key Laboratory of Cellular Physiology at Shanxi Medical University, Ministry of Education, Taiyuan, China
- Shanxi Provincial Key Laboratory of Rheumatism Immune Microecology, The Second Hospital of Shanxi Medical University, Taiyuan, China
| | - Duo Yuan
- Department of Gynecology and Obstetrics, The Second Hospital of Shanxi Medical University, Taiyuan, China
| | - Sheng-Xiao Zhang
- Department of Rheumatology, The Second Hospital of Shanxi Medical University, Taiyuan, China
- Key Laboratory of Cellular Physiology at Shanxi Medical University, Ministry of Education, Taiyuan, China
- Shanxi Provincial Key Laboratory of Rheumatism Immune Microecology, The Second Hospital of Shanxi Medical University, Taiyuan, China
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2
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Kim ES, Yoon BH, Lee SM, Choi M, Kim EH, Lee BW, Kim SY, Pack CG, Sung YH, Baek IJ, Jung CH, Kim TB, Jeong JY, Ha CH. Fecal microbiota transplantation ameliorates atherosclerosis in mice with C1q/TNF-related protein 9 genetic deficiency. Exp Mol Med 2022; 54:103-114. [PMID: 35115674 PMCID: PMC8894390 DOI: 10.1038/s12276-022-00728-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 10/20/2021] [Accepted: 10/28/2021] [Indexed: 12/13/2022] Open
Abstract
Despite the strong influence of the gut microbiota on atherosclerosis, a causal relationship between atherosclerosis pathophysiology and gut microbiota is still unverified. This study was performed to determine the impact of the gut microbiota on the pathogenesis of atherosclerosis caused by genetic deficiency. To elucidate the influence of the gut microbiota on atherosclerosis pathogenesis, an atherosclerosis-prone mouse model (C1q/TNF-related protein 9-knockout (CTRP9-KO) mice) was generated. The gut microbial compositions of CTRP9-KO and WT control mice were compared. Fecal microbiota transplantation (FMT) was performed to confirm the association between gut microbial composition and the progression of atherosclerosis. FMT largely affected the gut microbiota in both CTRP9-KO and WT mice, and all transplanted mice acquired the gut microbiotas of the donor mice. Atherosclerotic lesions in the carotid arteries were decreased in transplanted CTRP9-KO mice compared to CTRP9-KO mice prior to transplantation. Conversely, WT mice transplanted with the gut microbiotas of CTRP9-KO mice showed the opposite effect as that of CTRP9-KO mice transplanted with the gut microbiotas of WT mice. Here, we show that CTRP9 gene deficiency is related to the distribution of the gut microbiota in subjects with atherosclerosis. Transplantation of WT microbiotas into CTRP9-KO mice protected against the progression of atherosclerosis. Conversely, the transplantation of CTRP9-KO microbiotas into WT mice promoted the progression of atherosclerosis. Treating atherosclerosis by restoring gut microbial homeostasis may be an effective therapeutic strategy.
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Affiliation(s)
- Eun Sil Kim
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Bo Hyun Yoon
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seung Min Lee
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Min Choi
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Eun Hye Kim
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Byong-Wook Lee
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- ConveRgence mEDIcine research cenTer (CREDIT), Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Sang-Yeob Kim
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- ConveRgence mEDIcine research cenTer (CREDIT), Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Chan-Gi Pack
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- ConveRgence mEDIcine research cenTer (CREDIT), Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Young Hoon Sung
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- ConveRgence mEDIcine research cenTer (CREDIT), Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - In-Jeoung Baek
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- ConveRgence mEDIcine research cenTer (CREDIT), Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Chang Hee Jung
- Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Tae-Bum Kim
- Department of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
| | - Jin-Yong Jeong
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
- Digestive Diseases Research Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
| | - Chang Hoon Ha
- Department of Convergence Medicine and Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
- Digestive Diseases Research Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
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3
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Yang KL, Lejeune A, Chang G, Scher JU, Koralov SB. Microbial-derived antigens and metabolites in spondyloarthritis. Semin Immunopathol 2021; 43:163-172. [PMID: 33569635 DOI: 10.1007/s00281-021-00844-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/20/2021] [Indexed: 12/30/2022]
Abstract
Spondyloarthritis (SpA) is a group of chronic, immune-mediated, inflammatory diseases affecting the bone, synovium, and enthesis. Microbiome, the community of microorganisms that has co-evolved with human hosts, plays a pivotal role in human health and disease. This invisible "essential organ" supplies the host with a myriad of chemicals and molecules. In turn, microbial metabolites can serve as messengers for microbes to communicate with each other and in the cross-talk with host cells. Gut dysbiosis in SpA is associated with altered microbial metabolites, and an accumulated body of research has contributed to the understanding that changes in intestinal microbiota can modulate disease pathogenesis. We review the novel findings from human and animal studies to provide an overview of the contribution of individual microbial metabolites and antigens to SpA.
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Affiliation(s)
- Katharine Lu Yang
- Department of Pathology, NYU School of Medicine, 522 First Ave. Smilow Research Bldg 511, New York, NY, 10016, USA
| | - Alannah Lejeune
- Department of Pathology, NYU School of Medicine, 522 First Ave. Smilow Research Bldg 511, New York, NY, 10016, USA
| | - Gregory Chang
- Department of Radiology, NYU School of Medicine, New York, NY, 10016, USA
| | - Jose U Scher
- Division of Rheumatology, Department of Medicine, NYU School of Medicine, New York, NY, 10016, USA. .,Division of Rheumatology and Psoriatic Arthritis Center, 301 East 17th St, Room 1608, New York, NY, 10003, USA.
| | - Sergei B Koralov
- Department of Pathology, NYU School of Medicine, 522 First Ave. Smilow Research Bldg 511, New York, NY, 10016, USA.
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Khan A, Ding Z, Ishaq M, Bacha AS, Khan I, Hanif A, Li W, Guo X. Understanding the Effects of Gut Microbiota Dysbiosis on Nonalcoholic Fatty Liver Disease and the Possible Probiotics Role: Recent Updates. Int J Biol Sci 2021; 17:818-833. [PMID: 33767591 PMCID: PMC7975705 DOI: 10.7150/ijbs.56214] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 12/24/2020] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is leading chronic liver syndrome worldwide. Gut microbiota dysbiosis significantly contributes to the pathogenesis and severity of NAFLD. However, its role is complex and even unclear. Treatment of NAFLD through chemotherapeutic agents have been questioned because of their side effects on health. In this review, we highlighted and discussed the current understanding on the importance of gut microbiota, its dysbiosis and its effects on the gut-liver axis and gut mucosa. Further, we discussed key mechanisms involved in gut dysbiosis to provide an outline of its role in progression to NAFLD and liver cirrhosis. In addition, we also explored the potential role of probiotics as a treatment approach for the prevention and treatment of NAFLD. Based on the latest findings, it is evident that microbiota targeted interventions mostly the use of probiotics have shown promising effects and can possibly alleviate the gut microbiota dysbiosis, regulate the metabolic pathways which in turn inhibit the progression of NAFLD through the gut-liver axis. However, very limited studies in humans are available on this issue and suggest further research work to identify a specific core microbiome association with NAFLD and to discover its mechanism of pathogenesis, which will help to enhance the therapeutic potential of probiotics to NAFLD.
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Affiliation(s)
- Ashiq Khan
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
- Department of Microbiology, Balochistan University of Information Technology Engineering & Management Sciences Quetta 87300, Pakistan
| | - Zitong Ding
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
| | - Muhammad Ishaq
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
| | - Ali Sher Bacha
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
| | - Israr Khan
- School of Life Sciences, Institute of Microbiology Lanzhou University, Lanzhou 730000, PR China
| | - Anum Hanif
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
| | - Wenyuan Li
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
| | - Xusheng Guo
- School of Life Sciences, Probiotics and Biological Feed Research Centre, Lanzhou University, Lanzhou 730000, PR China
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5
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Zheng Y, Tang Z, You L, Wu Y, Liu J, Xue J. Trimethylamine- N-oxide is an independent risk factor for hospitalization events in patients receiving maintenance hemodialysis. Ren Fail 2020; 42:580-586. [PMID: 32576072 PMCID: PMC7946050 DOI: 10.1080/0886022x.2020.1781170] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Background Hospitalization is a significant outcome measurement for maintenance hemodialysis pantients. Trimethylamine-N-oxide (TMAO), created by gut microflora from dietary l-carnitine and choline, cleared by the kidney, has been implicated in the causation of cardiovascular diseases in patients with chronic kidney disease. However, whether it associates with hospitalization risk for these patients is unclear. Methods In this study, 69 patients undergoing outpatient dialysis were enrolled. Enzyme-linked immunosorbent assay was used to quantitate the baseline plasma TMAO levels in patients. The patients were divided into a high TMAO level group (TMAO ≥ 15 μmol/L) and a low TMAO level group (TMAO < 15 μmol/L). During the 1-year follow-up, 1-year dialysis-related data and all-cause hospitalization events were recorded. Results The incidence of hospitalization events was significantly higher in the high TMAO level group than in the low TMAO level group (91 per 100 patient-year vs. 32 per 100 patient-year). The Kaplain–Meier survaial analysis showed that the incidence of hospitalization events in the high TMAO level group was significantly higher than that in the low TMAO level group (log-rank p = 0.0004). After adjustment age, sex, CK-MB and albumin, the results of multivariate Cox proportional hazard analysis showed that high TMAO level was an independent risk factor for hospitalization in maintenance hemodialysis patients. Conclusion TMAO is an independent risk factor for hospitalization events in patients receiving maintenance hemodialysis. It may be a new therapeutic target for improving the outcomes of these patients.
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Affiliation(s)
- Yin Zheng
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Zihui Tang
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Li You
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yuanhao Wu
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Junfeng Liu
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
| | - Jun Xue
- Department of Nephrology, Huashan Hospital, Fudan University, Shanghai, China
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6
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Dai Y, Tian Q, Si J, Sun Z, Shali S, Xu L, Ren D, Chang S, Dong X, Zhao H, Mei Z, Zheng Y, Ge J. Circulating metabolites from the choline pathway and acute coronary syndromes in a Chinese case-control study. Nutr Metab (Lond) 2020; 17:39. [PMID: 32489394 PMCID: PMC7245747 DOI: 10.1186/s12986-020-00460-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/07/2020] [Indexed: 12/23/2022] Open
Abstract
Background Accumulating evidence shows that circulating levels of trimethylamine N-oxide, which is generated from the metabolism of dietary choline, may predict cardiovascular disease among Caucasians. Acute coronary syndrome (ACS), one common presentation of cardiovascular disease, is a spectrum of signs and symptoms due to acute decreased blood flow in the coronary arteries. The relationship between the metabolites from choline pathway and ACS remains unclear. We aimed to assess the associations of circulating metabolites from the choline pathway with ACS among a Chinese population, who consume a different dietary pattern than their Western counterparts. Methods We recruited 501 participants who were admitted to the Department of Cardiology, Zhongshan Hospital,Shanghai China between March 2017 and June 2018, including 254 ACS cases and 247 controls. Liquid chromatography-tandem mass spectrometry was used to measure circulating concentrations of metabolites in the choline pathway, including betaine, choline, trimethylamine, and trimethylamine N-oxide. A composite metabolite score using a weighted sum of these four metabolites, and the betaine/choline ratio were calculated. Multivariable logistic regressions were applied to estimate the association of metabolites with ACS, with adjustment of age, sex, body mass index, smoking index, history of diseases, and kidney function. Results After adjusting for traditional risk factors, per 1-standard deviation (SD) increment in choline was positively associated with the odds of ACS [odds ratio (OR), 95% confidence interval (CI), 1.77(1.44-2.18)], and the other metabolites were not associated with ACS at a statistical significance level. Compared with participants in the lowest quartile of the metabolite score, those in the highest quartile had higher odds of ACS [OR (95% CI), 3.18(1.85-5.54), p < 0.001 for trend]. Per 1-SD increment in metabolite score was positively associated with higher odds of ACS [OR (95% CI), 1.80 (1.37-2.40)], and per 1-SD increment in the betaine/choline ratio was inversely associated with the odds of ACS [OR (95% CI), 0.49 (0.39-0.60)]. Conclusions Among our Chinese participants, trimethylamine N-oxide was not associated with ACS, while a composite metabolite score of metabolites from the choline pathway was associated with increased odds of ACS. The choline pathway metabolites may be related to the pathophysiology of ACS among Chinese.
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Affiliation(s)
- Yuxiang Dai
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China
| | - Qianqian Tian
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China.,Department of Anthropology and Human Genetics, School of Life Sciences, Fudan University, Shanghai, China.,School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Jing Si
- Human Phenome Institute, Fudan University, 2005 Songhu Road, Shanghai, 200438 China
| | - Zhonghan Sun
- Department of Anthropology and Human Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Shalaimaiti Shali
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China
| | - Lili Xu
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China
| | - Daoyuan Ren
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China
| | - Shufu Chang
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China
| | - Xin Dong
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China.,Institute of translational medicine, Shanghai University, Shanghai, China
| | - Hongxia Zhao
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China.,Institute of translational medicine, Shanghai University, Shanghai, China
| | - Zhendong Mei
- Department of Anthropology and Human Genetics, School of Life Sciences, Fudan University, Shanghai, China
| | - Yan Zheng
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China.,Department of Anthropology and Human Genetics, School of Life Sciences, Fudan University, Shanghai, China.,Human Phenome Institute, Fudan University, 2005 Songhu Road, Shanghai, 200438 China
| | - Junbo Ge
- Department of Cardiology, Shanghai Institute of Cardiovascular Disease, ZhongShan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032 China
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Fernández-García M, Rey-Stolle F, Boccard J, Reddy VP, García A, Cumming BM, Steyn AJC, Rudaz S, Barbas C. Comprehensive Examination of the Mouse Lung Metabolome Following Mycobacterium tuberculosis Infection Using a Multiplatform Mass Spectrometry Approach. J Proteome Res 2020; 19:2053-2070. [PMID: 32285670 PMCID: PMC7199213 DOI: 10.1021/acs.jproteome.9b00868] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Indexed: 02/08/2023]
Abstract
The mechanisms whereby Mycobacterium tuberculosis (Mtb) rewires the host metabolism in vivo are surprisingly unexplored. Here, we used three high-resolution mass spectrometry platforms to track altered lung metabolic changes associated with Mtb infection of mice. The multiplatform data sets were merged using consensus orthogonal partial least squares-discriminant analysis (cOPLS-DA), an algorithm that allows for the joint interpretation of the results from a single multivariate analysis. We show that Mtb infection triggers a temporal and progressive catabolic state to satisfy the continuously changing energy demand to control infection. This causes dysregulation of metabolic and oxido-reductive pathways culminating in Mtb-associated wasting. Notably, high abundances of trimethylamine-N-oxide (TMAO), produced by the host from the bacterial metabolite trimethylamine upon infection, suggest that Mtb could exploit TMAO as an electron acceptor under anaerobic conditions. Overall, these new pathway alterations advance our understanding of the link between Mtb pathogenesis and metabolic dysregulation and could serve as a foundation for new therapeutic intervention strategies. Mass spectrometry data has been deposited in the Metabolomics Workbench repository (data-set identifier: ST001328).
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Affiliation(s)
- Miguel Fernández-García
- Centro
de Metabolómica y Bioanálisis (CEMBIO), Facultad de
Farmacia, Universidad San Pablo-CEU, CEU
Universities, Urbanización Montepríncipe, Boadilla del Monte 28660, Spain
| | - Fernanda Rey-Stolle
- Centro
de Metabolómica y Bioanálisis (CEMBIO), Facultad de
Farmacia, Universidad San Pablo-CEU, CEU
Universities, Urbanización Montepríncipe, Boadilla del Monte 28660, Spain
| | - Julien Boccard
- School
of Pharmaceutical Sciences, University of
Lausanne and University of Geneva, Geneva 1211, Switzerland
| | - Vineel P. Reddy
- Department
of Microbiology, University of Alabama at
Birmingham, Birmingham, Alabama 35294, United States
| | - Antonia García
- Centro
de Metabolómica y Bioanálisis (CEMBIO), Facultad de
Farmacia, Universidad San Pablo-CEU, CEU
Universities, Urbanización Montepríncipe, Boadilla del Monte 28660, Spain
| | | | - Adrie J. C. Steyn
- Department
of Microbiology, University of Alabama at
Birmingham, Birmingham, Alabama 35294, United States
- Africa
Health Research Institute, Durban 4001, South Africa
- UAB
Centers for AIDS Research and Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Serge Rudaz
- School
of Pharmaceutical Sciences, University of
Lausanne and University of Geneva, Geneva 1211, Switzerland
| | - Coral Barbas
- Centro
de Metabolómica y Bioanálisis (CEMBIO), Facultad de
Farmacia, Universidad San Pablo-CEU, CEU
Universities, Urbanización Montepríncipe, Boadilla del Monte 28660, Spain
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8
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Borges NA, Stenvinkel P, Bergman P, Qureshi AR, Lindholm B, Moraes C, Stockler-Pinto MB, Mafra D. Effects of Probiotic Supplementation on Trimethylamine-N-Oxide Plasma Levels in Hemodialysis Patients: a Pilot Study. Probiotics Antimicrob Proteins 2020; 11:648-654. [PMID: 29651635 DOI: 10.1007/s12602-018-9411-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Components present in the diet, L-carnitine, choline, and betaine are metabolized by gut microbiota to produce metabolites such as trimethylamine-N-oxide (TMAO) that appear to promote cardiovascular disease in chronic kidney disease (CKD) patients. The objective of this pilot study was to evaluate the effects of probiotic supplementation for 3 months on plasma TMAO levels in CKD patients on hemodialysis (HD). A randomized, double-blind trial was performed in 21 patients [54.8 ± 10.4 years, nine men, BMI 26.1 ± 4.8 kg/m2, dialysis vintage 68.5 (34.2-120.7) months]. Ten patients were randomly allocated to the placebo group and 11 to the probiotic group [three capsules, totaling 9 × 1013 colony-forming units per day of Streptococcus thermophilus (KB19), Lactobacillus acidophilus (KB27), and Bifidobacteria longum (KB31). Plasma TMAO, choline, and betaine levels were measured by LC-MS/MS at baseline and after 3 months. While TMAO did not change after probiotic supplementation, there was a significant increase in betaine plasma levels. In contrast, the placebo group showed a significant decrease in plasma choline levels. Short-term probiotic supplementation does not appear to influence plasma TMAO levels in HD patients. Long-term studies are needed to determine whether probiotics may affect TMAO production in CKD patients.
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Affiliation(s)
- Natália A Borges
- Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niterói, RJ, Brazil. .,Unidade de Pesquisa Clínica, Rua Marques do Paraná, 303, Niterói, RJ, 24033-900, Brazil.
| | - P Stenvinkel
- Department of Clinical Science Intervention and Technology, Division of Renal Medicine and Baxter Novum, Karolinska Institutet, Stockholm, Sweden
| | - P Bergman
- Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital, Huddinge, Stockholm, Sweden
| | - A R Qureshi
- Department of Clinical Science Intervention and Technology, Division of Renal Medicine and Baxter Novum, Karolinska Institutet, Stockholm, Sweden
| | - B Lindholm
- Department of Clinical Science Intervention and Technology, Division of Renal Medicine and Baxter Novum, Karolinska Institutet, Stockholm, Sweden
| | - C Moraes
- Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niterói, RJ, Brazil
| | - M B Stockler-Pinto
- Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niterói, RJ, Brazil.,Unidade de Pesquisa Clínica, Rua Marques do Paraná, 303, Niterói, RJ, 24033-900, Brazil
| | - D Mafra
- Graduate Program in Cardiovascular Sciences, Fluminense Federal University (UFF), Niterói, RJ, Brazil.,Unidade de Pesquisa Clínica, Rua Marques do Paraná, 303, Niterói, RJ, 24033-900, Brazil.,Graduate Program in Medical Sciences, Fluminense Federal University (UFF), Niterói, RJ, Brazil
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9
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Xu N, Kan P, Yao X, Yang P, Wang J, Xiang L, Zhu Y. Astragaloside IV reversed the autophagy and oxidative stress induced by the intestinal microbiota of AIS in mice. J Microbiol 2018; 56:838-846. [PMID: 30353470 DOI: 10.1007/s12275-018-8327-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/06/2018] [Accepted: 08/06/2018] [Indexed: 02/06/2023]
Abstract
Acute ischaemic stroke (AIS) seriously affects patient quality of life. We explored the role of the intestinal microbiota on oxidative stress and autophagy in stroke, and Astragaloside IV (AS-IV) reversed the changes induced by intestinal microbiota. We determined the characteristics of the intestinal microbiota of AIS and transient ischaemic attack (TIA) patients by 16S sequencing and found that the structure and diversity of the intestinal microbiota in patients with AIS and TIA were significantly different from those in healthy subjects. Specifically, the abundance of genus Bifidobacterium, Megamonas, Blautia, Holdemanella, and Clostridium, content of homocysteine and triglyceride was increased significantly, thus it may be as a potential mechanism of AIS and TIA. Furthermore, germ-free mice were infused intracolonically with fecal supernatants of TIA and AIS with/without feed AS-IV for 12 weeks, and we found that the feces of AIS up-regulated the autophagy markers Beclin-1, light chain 3 (LC3)-II and autophagy-related gene (Atg)12, and the expression of reactive oxygen species (ROS) and NADPH oxidase 2/4 (NOX2/4), malondialdehyde (MDA), however, the expression of total antioxidant capacity (T-AOC) and activity of superoxide dismutase (SOD) and glutathione (GSH) was down-regulated in brain tissue, the content of homocysteine and free fatty acids (FFA) in serum of the mice. Meanwhile, AS-IV could reverse the above phenomenon, however, it does not affect the motor function of mice. AS-IV reversed these changes and it may be a potential drug for AIS therapeutics.
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Affiliation(s)
- Nan Xu
- Department of Infections Diseases, Tianjin Medical University General Hospital, Tianjin, 300052, P. R. China.
| | - Pengcheng Kan
- Department of Clinical Laboratory, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China.,Tianjin Key Laboratory of Cerebral Vessels and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China
| | - Xiuhua Yao
- Tianjin Key Laboratory of Cerebral Vessels and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China.,Tianjin Neurosurgery Institute, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China
| | - Ping Yang
- Department of Clinical Laboratory, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China.,Tianjin Key Laboratory of Cerebral Vessels and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China
| | - Jiwei Wang
- Tianjin Key Laboratory of Cerebral Vessels and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China.,Department of Neurosurgery, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China
| | - Lei Xiang
- Tianjin Key Laboratory of Cerebral Vessels and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China. .,Department of Neurology, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China.
| | - Yu Zhu
- Department of Clinical Laboratory, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China. .,Tianjin Key Laboratory of Cerebral Vessels and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, 300350, P. R. China.
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10
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Jameson E, Quareshy M, Chen Y. Methodological considerations for the identification of choline and carnitine-degrading bacteria in the gut. Methods 2018; 149:42-48. [PMID: 29684641 PMCID: PMC6200775 DOI: 10.1016/j.ymeth.2018.03.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/14/2018] [Accepted: 03/26/2018] [Indexed: 12/19/2022] Open
Abstract
The bacterial formation of trimethylamine (TMA) has been linked to cardiovascular disease. This review focuses on the methods employed to investigate the identity of the bacteria responsible for the formation of TMA from dietary choline and carnitine in the human gut. Recent studies have revealed the metabolic pathways responsible for bacterial TMA production, primarily the anaerobic glycyl radical-containing, choline-TMA lyase, CutC and the aerobic carnitine monooxygenase, CntA. Identification of these enzymes has enabled bioinformatics approaches to screen both human-associated bacterial isolate genomes and whole gut metagenomes to determine which bacteria are responsible for TMA formation in the human gut. We centre on several key methodological aspects for identifying the TMA-producing bacteria and report how these pathways can be identified in human gut microbiota through bioinformatics analysis of available bacterial genomes and gut metagenomes.
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Affiliation(s)
- Eleanor Jameson
- The University of Warwick, School of Life Sciences, United Kingdom.
| | - Mussa Quareshy
- The University of Warwick, School of Life Sciences, United Kingdom
| | - Yin Chen
- The University of Warwick, School of Life Sciences, United Kingdom
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11
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Bu J, Wang Z. Cross-Talk between Gut Microbiota and Heart via the Routes of Metabolite and Immunity. Gastroenterol Res Pract. 2018;2018:6458094. [PMID: 29967639 PMCID: PMC6008745 DOI: 10.1155/2018/6458094] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 05/16/2018] [Indexed: 12/13/2022] Open
Abstract
Considering the prevalence of cardiovascular disease (CVD), significant interest has been focused on the gut microbiota-heart interaction because the gut microbiota has been recognized as a barometer of human health. Dysbiosis, characterized by changes in the gut microbiota in CVD, has been reported in cardiovascular pathologies, such as atherosclerosis, hypertension, and heart failure. Conversely, gut microbiota-derived metabolites, such as trimethylamine/trimethylamine N-oxide (TMA/TMAO), can impact host physiology. Further, bacterial dysbiosis can disturb gut immunity, which increases the risk of acute arterial events. Moreover, studies of germ-free mice have provided evidence that microbiota diversity and the presence of a specific microbe in the gut can affect immune cells in hosts. Therefore, the changes in the composition of the gut microbiota can affect host metabolism and immunity. Importantly, these effects are not only confined to the gut but also spreaded to distal organs. The purpose of the current review is to highlight the complex interplay between the microbiota and CVD via TMAO and different immune cells and discuss the roles of probiotics and nutrition interventions in modulating the intestinal microbiota as novel therapeutic targets of CVD.
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12
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Bajaj JS, Kakiyama G, Cox IJ, Nittono H, Takei H, White M, Fagan A, Gavis EA, Heuman DM, Gilles HC, Hylemon P, Taylor-Robinson SD, Legido-Quigley C, Kim M, Xu J, Williams R, Sikaroodi M, Pandak WM, Patrick MG. Alterations in gut microbial function following liver transplant. Liver Transpl 2018; 24:752-761. [PMID: 29500907 PMCID: PMC5992060 DOI: 10.1002/lt.25046] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/16/2018] [Accepted: 02/25/2018] [Indexed: 12/12/2022]
Abstract
Liver transplantation (LT) improves daily function and ameliorates gut microbial composition. However, the effect of LT on microbial functionality, which can be related to overall patient benefit, is unclear and could affect the post-LT course. The aims were to determine the effect of LT on gut microbial functionality focusing on endotoxemia, bile acid (BA), ammonia metabolism, and lipidomics. We enrolled outpatient patients with cirrhosis on the LT list and followed them until 6 months after LT. Microbiota composition (Shannon diversity and individual taxa) and function analysis (serum endotoxin, urinary metabolomics and serum lipidomics, and stool BA profile) and cognitive tests were performed at both visits. We enrolled 40 patients (age, 56 ± 7 years; mean Model for End-Stage Liver Disease score, 22.6). They received LT 6 ± 3 months after enrollment and were re-evaluated 7 ± 3 months after LT with a stable course. A significant improvement in cognition with increase in microbial diversity, increase in autochthonous and decrease in potentially pathogenic taxa, and reduced endotoxemia were seen after LT compared with baseline. Stool BAs increased significantly after LT, and there was evidence of greater bacterial action (higher secondary, oxo and iso-BAs) after LT although the levels of conjugated BAs remained similar. There was a reduced serum ammonia and corresponding rise in urinary phenylacetylglutamine after LT. There was an increase in urinary trimethylamine-N-oxide, which was correlated with specific changes in serum lipids related to cell membrane products. The ultimate post-LT lipidomic profile appeared beneficial compared with the profile before LT. In conclusion, LT improves gut microbiota diversity and dysbiosis, which is accompanied by favorable changes in gut microbial functionality corresponding to BAs, ammonia, endotoxemia, lipidomic, and metabolomic profiles. Liver Transplantation 24 752-761 2018 AASLD.
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Affiliation(s)
- Jasmohan S. Bajaj
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - Genta Kakiyama
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - I. Jane Cox
- Institute of Hepatology, London, Foundation for Liver Research, London UK
| | | | - Hajime Takei
- Junshin Clinic Bile Acid Institute, Tokyo, Japan
| | - Melanie White
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - Andrew Fagan
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - Edith A. Gavis
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - Douglas M. Heuman
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - Ho Chong Gilles
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | - Phillip Hylemon
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
| | | | | | - Min Kim
- Faculty of Life Sciences & Medicine, Kings College, London, UK
| | - Jin Xu
- Faculty of Life Sciences & Medicine, Kings College, London, UK
| | - Roger Williams
- Institute of Hepatology, London, Foundation for Liver Research, London UK
| | | | - William M. Pandak
- Virginia Commonwealth University and McGuire Veterans Affairs Medical Center, Richmond, VA, USA
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13
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Li Z, Suslick KS. Ultrasonic Preparation of Porous Silica-Dye Microspheres: Sensors for Quantification of Urinary Trimethylamine N-Oxide. ACS Appl Mater Interfaces 2018; 10:15820-15828. [PMID: 29694015 DOI: 10.1021/acsami.8b00995] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Trimethylamine N-oxide (TMAO), the N-oxide metabolite of trimethylamine (TMA), is a key index in the determination of a wide variety of human cardiac or kidney diseases. A colorimetric sensor array comprising ultrasonically prepared silica-dye microspheres was developed for rapid, portable, and sensitive detection of urinary TMAO. To prepare the sensor array, 13 different organically modified silica (ormosil)-dye composites were synthesized from the hydrolysis/pyrolysis of ultrasonically sprayed organosiloxane precursors under optimized reaction conditions; the resulting products are uniformly sized nanoporous microspheres that are effective colorimetric sensors for various volatile analytes. The effective quantification of aqueous TMAO (which is not volatile) was based on sensing the volatile TMA produced from a simple catalytic reduction of TMAO in situ. RGB color-change patterns from digital images of the sensor array permit precise discrimination among a wide range of TMAO concentrations (10-750 μM) in simulated urine samples; both hierarchical cluster analysis and principal component analysis achieve >99% accuracy in data classification. The calculated limit of detection of urinary TMAO is ∼4 μM, which is substantially below the median level of healthy subjects (∼380 μM). The array of sensors could be simplified to only a couple of strongly responsive elements for the ease of field use, and the process could be developed as a point-of-care tool in combination with digital imaging for the early diagnosis of cardiovascular or kidney diseases from the measurement of fasting urinary level of TMAO.
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Affiliation(s)
- Zheng Li
- Department of Chemistry , University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue , Urbana , Illinois 61801 , United States
| | - Kenneth S Suslick
- Department of Chemistry , University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue , Urbana , Illinois 61801 , United States
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14
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Velasquez MT, Ramezani A, Manal A, Raj DS. Trimethylamine N-Oxide: The Good, the Bad and the Unknown. Toxins (Basel) 2016; 8:E326. [PMID: 27834801 DOI: 10.3390/toxins8110326] [Citation(s) in RCA: 298] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/31/2016] [Accepted: 11/03/2016] [Indexed: 12/12/2022] Open
Abstract
Trimethylamine N-oxide (TMAO) is a small colorless amine oxide generated from choline, betaine, and carnitine by gut microbial metabolism. It accumulates in the tissue of marine animals in high concentrations and protects against the protein-destabilizing effects of urea. Plasma level of TMAO is determined by a number of factors including diet, gut microbial flora and liver flavin monooxygenase activity. In humans, a positive correlation between elevated plasma levels of TMAO and an increased risk for major adverse cardiovascular events and death is reported. The atherogenic effect of TMAO is attributed to alterations in cholesterol and bile acid metabolism, activation of inflammatory pathways and promotion foam cell formation. TMAO levels increase with decreasing levels of kidney function and is associated with mortality in patients with chronic kidney disease. A number of therapeutic strategies are being explored to reduce TMAO levels, including use of oral broad spectrum antibiotics, promoting the growth of bacteria that utilize TMAO as substrate and the development of target-specific molecules with varying level of success. Despite the accumulating evidence, it is questioned whether TMAO is the mediator of a bystander in the disease process. Thus, it is important to undertake studies examining the cellular signaling in physiology and pathological states in order to establish the role of TMAO in health and disease in humans.
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15
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Jameson E, Doxey AC, Airs R, Purdy KJ, Murrell JC, Chen Y. Metagenomic data-mining reveals contrasting microbial populations responsible for trimethylamine formation in human gut and marine ecosystems. Microb Genom 2016; 2:e000080. [PMID: 28785417 PMCID: PMC5537630 DOI: 10.1099/mgen.0.000080] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 07/19/2016] [Indexed: 01/20/2023] Open
Abstract
Existing metagenome datasets from many different environments contain untapped potential for understanding metabolic pathways and their biological impact. Our interest lies in the formation of trimethylamine (TMA), a key metabolite in both human health and climate change. Here, we focus on bacterial degradation pathways for choline, carnitine, glycine betaine and trimethylamine N-oxide (TMAO) to TMA in human gut and marine metagenomes. We found the TMAO reductase pathway was the most prevalent pathway in both environments. Proteobacteria were found to contribute the majority of the TMAO reductase pathway sequences, except in the stressed gut, where Actinobacteria dominated. Interestingly, in the human gut metagenomes, a high proportion of the Proteobacteria hits were accounted for by the genera Klebsiella and Escherichia. Furthermore Klebsiella and Escherichia harboured three of the four potential TMA-production pathways (choline, carnitine and TMAO), suggesting they have a key role in TMA cycling in the human gut. In addition to the intensive TMAO-TMA cycling in the marine environment, our data suggest that carnitine-to-TMA transformation plays an overlooked role in aerobic marine surface waters, whereas choline-to-TMA transformation is important in anaerobic marine sediments. Our study provides new insights into the potential key microbes and metabolic pathways for TMA formation in two contrasting environments.
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Affiliation(s)
- Eleanor Jameson
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, CV4 7AL, UK
| | - Andrew C. Doxey
- Department of Biology, University of Waterloo, 200 University Ave. W, Waterloo, Ontario N2L 3G1, Canada
| | - Ruth Airs
- Plymouth Marine Laboratory, Prospect Pl, Plymouth PL1 3DH, UK
| | - Kevin J. Purdy
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, CV4 7AL, UK
| | - J. Colin Murrell
- University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Yin Chen
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, CV4 7AL, UK
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16
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Vitetta L, Hall S, Coulson S. Metabolic Interactions in the Gastrointestinal Tract (GIT): Host, Commensal, Probiotics, and Bacteriophage Influences. Microorganisms 2015; 3:913-32. [PMID: 27682125 PMCID: PMC5023274 DOI: 10.3390/microorganisms3040913] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 11/25/2015] [Accepted: 12/07/2015] [Indexed: 12/25/2022] Open
Abstract
Life on this planet has been intricately associated with bacterial activity at all levels of evolution and bacteria represent the earliest form of autonomous existence. Plants such as those from the Leguminosae family that form root nodules while harboring nitrogen-fixing soil bacteria are a primordial example of symbiotic existence. Similarly, cooperative activities between bacteria and animals can also be observed in multiple domains, including the most inhospitable geographical regions of the planet such as Antarctica and the Lower Geyser Basin of Yellowstone National Park. In humans bacteria are often classified as either beneficial or pathogenic and in this regard we posit that this artificial nomenclature is overly simplistic and as such almost misinterprets the complex activities and inter-relationships that bacteria have with the environment as well as the human host and the plethora of biochemical activities that continue to be identified. We further suggest that in humans there are neither pathogenic nor beneficial bacteria, just bacteria embraced by those that tolerate the host and those that do not. The densest and most complex association exists in the human gastrointestinal tract, followed by the oral cavity, respiratory tract, and skin, where bacteria—pre- and post-birth—instruct the human cell in the fundamental language of molecular biology that normally leads to immunological tolerance over a lifetime. The overall effect of this complex output is the elaboration of a beneficial milieu, an environment that is of equal or greater importance than the bacterium in maintaining homeostasis.
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Affiliation(s)
- Luis Vitetta
- Medlab Clinical Ltd., Sydney 2015 Australia.
- Sydney Medical School, University of Sydney, Sydney 2006, Australia.
| | - Sean Hall
- Medlab Clinical Ltd., Sydney 2015 Australia.
| | - Samantha Coulson
- Medlab Clinical Ltd., Sydney 2015 Australia.
- Sydney Medical School, University of Sydney, Sydney 2006, Australia.
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