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Rodrigues FSC, Brilhante D, Macêdo A, Pires RF, Faria M. Ibuprofen-Immobilized Thin Films: A Novel Approach to Improve the Clearance of Protein-Bound Uremic Toxins. ACS APPLIED MATERIALS & INTERFACES 2024; 16:6589-6604. [PMID: 38282580 DOI: 10.1021/acsami.3c15291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
Chronic kidney disease (CKD), a pressing global health issue, affects millions and leads to end-stage renal disease (ESRD). Hemodialysis (HD) is a crucial treatment for ESRD, yet its limited efficiency in removing protein-bound uremic toxins (PBUTs) results in high morbidity and mortality rates. A high affinity of pharmaceutical drugs for human serum albumin (HSA) can be leveraged to compete effectively with PBUTs for the same HSA binding sites, thereby enabling them to be capable of displacing these toxins. One such drug is ibuprofen (IBF), known for its very high affinity for HSA and sharing the same binding site as indoxyl sulfate (IS). This study explores the development of IBF-immobilized cellulose acetate-based (CA-based) thin films. The films were created by reacting CA with IBF-modified silica precursors at varying concentrations. The presence of IBF in CA/TEOS/APTES-IBF-3 and CA/TEOS-IBF-25 films, containing 3 and 25 wt % IBF, respectively, was confirmed through 1H NMR spectra. Competitive displacement binding assays indicated that while the incorporation of 3 wt % IBF showed no significant enhancement in IS displacement, the 25 wt % IBF film increased the dialyzed IS by 1.3 when normalized to non-IBF films. Furthermore, there was a 1.2-fold decrease in the total percentage of IS, and the free percentage of IS increased 1.3 to 3.0 times. Although direct systemic infusion of IBF in HD patients achieves a 2.4 times higher removal of IS, it is impractical due to the risks it poses to ESRD patients. The IBF-immobilized films offer the advantage of localized binding, thus eliminating the need for systemic exposure. This innovative approach lays a foundation for developing more efficient HD membranes, aiming to address the challenging issue of PBUT elimination and potentially enhance the quality of life and treatment outcomes for ESRD patients.
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Affiliation(s)
- Flávia S C Rodrigues
- Laboratory of Physics of Materials and Emerging Technologies (LaPMET), Center of Physics and Engineering of Advanced Materials (CeFEMA), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Dialina Brilhante
- Serviço de Imunohemoterapia, Instituto Português de Oncologia de Lisboa Francisco Gentil (IPO Lisboa), R. Prof. Lima Basto, 1099-023 Lisbon, Portugal
| | - Ana Macêdo
- Serviço de Imunohemoterapia, Instituto Português de Oncologia de Lisboa Francisco Gentil (IPO Lisboa), R. Prof. Lima Basto, 1099-023 Lisbon, Portugal
| | - Rita F Pires
- Laboratory of Physics of Materials and Emerging Technologies (LaPMET), Center of Physics and Engineering of Advanced Materials (CeFEMA), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Mónica Faria
- Laboratory of Physics of Materials and Emerging Technologies (LaPMET), Center of Physics and Engineering of Advanced Materials (CeFEMA), Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
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Tang WHW, Nemet I, Li XS, Wu Y, Haghikia A, Witkowski M, Koeth RA, Demuth I, König M, Steinhagen-Thiessen E, Bäckhed F, Fischbach MA, Deb A, Landmesser U, Hazen SL. Prognostic value of gut microbe-generated metabolite phenylacetylglutamine in patients with heart failure. Eur J Heart Fail 2024; 26:233-241. [PMID: 38124458 DOI: 10.1002/ejhf.3111] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 11/30/2023] [Accepted: 12/19/2023] [Indexed: 12/23/2023] Open
Abstract
AIM Phenylacetylglutamine (PAGln) is a phenylalanine-derived metabolite produced by gut microbiota with mechanistic links to heart failure (HF)-relevant phenotypes. We sought to investigate the prognostic value of PAGln in patients with stable HF. METHODS AND RESULTS Fasting plasma PAGln levels were measured by stable-isotope-dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) in patients with stable HF from two large cohorts. All-cause mortality was assessed at 5-year follow-up in the Cleveland cohort, and HF, hospitalization, or mortality were assessed at 3-year follow-up in the Berlin cohort. Within the Cleveland cohort, median PAGln levels were 4.2 (interquartile range [IQR] 2.4-6.9) μM. Highest quartile of PAGln was associated with 3.09-fold increased mortality risk compared to lowest quartile. Following adjustments for traditional risk factors, as well as race, estimated glomerular filtration rate, amino-terminal pro-B-type natriuretic peptide, high-sensitivity C-reactive protein, left ventricular ejection fraction, ischaemic aetiology, and HF drug treatment, elevated PAGln levels remained predictive of 5-year mortality in quartile comparisons (adjusted hazard ratio [HR] [95% confidence interval, CI] for Q4 vs Q1: 1.64 [1.07-2.53]). In the Berlin cohort, a similar distribution of PAGln levels was observed (median 3.2 [IQR 2.0-4.8] μM), and PAGln levels were associated with a 1.92-fold increase in 3-year HF hospitalization or all-cause mortality risk (adjusted HR [95% CI] for Q4 vs Q1: 1.92 [1.02-3.61]). Prognostic value of PAGln appears to be independent of trimethylamine N-oxide levels. CONCLUSION High levels of PAGln are associated with adverse outcomes independent of traditional cardiac risk factors and cardio-renal risk markers.
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Affiliation(s)
- W H Wilson Tang
- Center for Microbiome and Human Health, Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Ina Nemet
- Center for Microbiome and Human Health, Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Xinmin S Li
- Center for Microbiome and Human Health, Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Yuping Wu
- Department of Mathematics and Statistics, Cleveland State University, Cleveland, OH, USA
| | - Arash Haghikia
- Department of Cardiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
- German Center for Cardiovascular Research (DZHK), Berlin, Germany
- Berlin Institute of Health (BIH), Berlin, Germany
| | - Marco Witkowski
- Center for Microbiome and Human Health, Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Robert A Koeth
- Center for Microbiome and Human Health, Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Ilja Demuth
- Department of Endocrinology and Metabolism, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies, Berlin, Germany
| | - Maximilian König
- Berlin Institute of Health (BIH), Berlin, Germany
- Department of Endocrinology and Metabolism, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Fredrik Bäckhed
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine and Sahlgrenska Center for Cardiovascular and Metabolic Research, University of Gothenburg, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Basic Metabolic Research Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - Michael A Fischbach
- Department of Bioengineering and ChEM-H, Stanford University, Stanford, CA, USA
| | - Arjun Deb
- Division of Cardiology and Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Ulf Landmesser
- Department of Cardiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
- German Center for Cardiovascular Research (DZHK), Berlin, Germany
- Berlin Institute of Health (BIH), Berlin, Germany
| | - Stanley L Hazen
- Center for Microbiome and Human Health, Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
- Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, OH, USA
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Lee CL, Liu WJ, Tsai SF. Effects of AST-120 on mortality in patients with chronic kidney disease modeled by artificial intelligence or traditional statistical analysis. Sci Rep 2024; 14:738. [PMID: 38184721 PMCID: PMC10771424 DOI: 10.1038/s41598-024-51498-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 01/05/2024] [Indexed: 01/08/2024] Open
Abstract
Chronic kidney disease (CKD) imposes a substantial burden, and patient prognosis remains grim. The impact of AST-120 (AST-120) on the survival of CKD patients lacks a consensus. This study aims to investigate the effects of AST-120 usage on the survival of CKD patients and explore the utility of artificial intelligence models for decision-making. We conducted a retrospective analysis of CKD patients receiving care in the pre-end-stage renal disease (ESRD) program at Taichung Veterans General Hospital from 2000 to 2019. We employed Cox regression models to evaluate the relationship between AST-120 use and patient survival, both before and after propensity score matching. Subsequently, we employed Deep Neural Network (DNN) and Extreme Gradient Boosting (XGBoost) models to assess their performance in predicting AST-120's impact on patient survival. Among the 2584 patients in our cohort, 2199 did not use AST-120, while 385 patients received AST-120. AST-120 users exhibited significantly lower mortality rates compared to non-AST-120 users (13.51% vs. 37.88%, p < 0.0001) and a reduced prevalence of ESRD (44.16% vs. 53.17%, p = 0.0005). Propensity score matching at 1:1 and 1:2 revealed no significant differences, except for dialysis and all-cause mortality, where AST-120 users exhibited significantly lower all-cause mortality (p < 0.0001), with a hazard ratio (HR) of 0.395 (95% CI = 0.295-0.522). This difference remained statistically significant even after propensity matching. In terms of model performance, the XGBoost model demonstrated the highest accuracy (0.72), specificity (0.90), and positive predictive value (0.48), while the logistic regression model showed the highest sensitivity (0.63) and negative predictive value (0.84). The area under the curve (AUC) values for logistic regression, DNN, and XGBoost were 0.73, 0.73, and 0.69, respectively, indicating similar predictive capabilities for mortality. In this cohort of CKD patients, the use of AST-120 is significantly associated with reduced mortality. However, the performance of artificial intelligence models in predicting the impact of AST-120 is not superior to statistical analysis using the current architecture and algorithm.
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Grants
- TCVGH-1093605D, TCVGH-1097316C, TCVGH-1097327D, TCVGH-1103502C, TCVGH-1107305D, TCVGH-1117308C, TCVGH-1117305D, TCVGH-1113602C, TCVGH-1113602D and TCVGH-1103601D Taichung Veterans General Hospital
- TCVGH-1093605D, TCVGH-1097316C, TCVGH-1097327D, TCVGH-1103502C, TCVGH-1107305D, TCVGH-1117308C, TCVGH-1117305D, TCVGH-1113602C, TCVGH-1113602D and TCVGH-1103601D Taichung Veterans General Hospital
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Affiliation(s)
- Chia-Lin Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
- Intelligent Data Mining Laboratory, Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
- Department of Public Health, College of Public Health, China Medical University, Taichung, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Wei-Ju Liu
- Intelligent Data Mining Laboratory, Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Shang-Feng Tsai
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan.
- Division of Nephrology, Taichung Veterans General Hospital, Taiwan, 160, Sec. 3, Taiwan Boulevard, Taichung, 407, Taiwan.
- Department of Life Science, Tunghai University, Taichung, Taiwan.
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Grosicki GJ, Langan SP, Bagley JR, Galpin AJ, Garner D, Hampton‐Marcell JT, Allen JM, Robinson AT. Gut check: Unveiling the influence of acute exercise on the gut microbiota. Exp Physiol 2023; 108:1466-1480. [PMID: 37702557 PMCID: PMC10988526 DOI: 10.1113/ep091446] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 09/04/2023] [Indexed: 09/14/2023]
Abstract
The human gastrointestinal microbiota and its unique metabolites regulate a diverse array of physiological processes with substantial implications for human health and performance. Chronic exercise training positively modulates the gut microbiota and its metabolic output. The benefits of chronic exercise for the gut microbiota may be influenced by acute changes in microbial community structure and function that follow a single exercise bout (i.e., acute exercise). Thus, an improved understanding of changes in the gut microbiota that occur with acute exercise could aid in the development of evidence-based exercise training strategies to target the gut microbiota more effectively. In this review, we provide a comprehensive summary of the existing literature on the acute and very short-term (<3 weeks) exercise responses of the gut microbiota and faecal metabolites in humans. We conclude by highlighting gaps in the literature and providing recommendations for future research in this area. NEW FINDINGS: What is the topic of this review? The chronic benefits of exercise for the gut microbiota are likely influenced by acute changes in microbial community structure and function that follow a single exercise bout. This review provides a summary of the existing literature on acute exercise responses of the gut microbiota and its metabolic output in humans. What advances does it highlight? Acute aerobic exercise appears to have limited effects on diversity of the gut microbiota, variable effects on specific microbial taxa, and numerous effects on the metabolic activity of gut microbes with possible implications for host health and performance.
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Affiliation(s)
| | - Sean P. Langan
- Korey Stringer Institute, Department of KinesiologyUniversity of ConnecticutStorrsCTUSA
| | - James R. Bagley
- Muscle Physiology LaboratorySan Francisco State UniversitySan FranciscoCAUSA
| | - Andrew J. Galpin
- Center for Sport PerformanceCalifornia State University, FullertonFullertonCAUSA
| | - Dan Garner
- BioMolecular Athlete, LLCWilmingtonDEUSA
| | | | - Jacob M. Allen
- Department of Kinesiology and Community HealthUniversity of Illinois at Urbana‐ChampaignUrbanaIL
| | - Austin T. Robinson
- Neurovascular Physiology Laboratory, School of KinesiologyAuburn UniversityAuburnALUSA
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Evans M, Dai L, Avesani CM, Kublickiene K, Stenvinkel P. The dietary source of trimethylamine N-oxide and clinical outcomes: an unexpected liaison. Clin Kidney J 2023; 16:1804-1812. [PMID: 37915930 PMCID: PMC10616480 DOI: 10.1093/ckj/sfad095] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Indexed: 11/03/2023] Open
Abstract
The profile of gut microbiota can vary according to host genetic and dietary characteristics, and be influenced by disease state and environmental stressors. The uremic dysbiosis results in a loss of biodiversity and overgrowth of microorganisms that may cause elevation of metabolic solutes such as trimethylamine N-oxide (TMAO), inducing pathogenic effects on its host. In patients with chronic kidney disease (CKD), TMAO levels are elevated because of a decreased clearance and an increased production from the uremic gut dysbiosis with a disrupted intestinal barrier and elevated enzymatic hepatic activity. Dietary precursors of TMAO are abundant in animal-derived foods such as red meat, egg yolk and other full-fat dietary products. TMAO is also found naturally in fish and certain types of seafood, with the TMAO content highly variable according to the depth of the sea where the fish is caught, as well as processing and storage. Although evidence points towards TMAO as being an important link to vascular damage and adverse cardiovascular outcomes, the evidence in CKD patients has not been consistent. In this review we discuss the potential dietary sources of TMAO and its actions on the intestinal microbiome as an explanation for the divergent results. We further highlight the potential of a healthy diet as one feasible therapeutic opportunity to prevent gut dysbiosis and reduce uremic toxin levels in patients with CKD.
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Affiliation(s)
- Marie Evans
- Renal Unit, Department of Clinical Sciences and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
| | - Lu Dai
- Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Carla Maria Avesani
- Renal Unit, Department of Clinical Sciences and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
| | - Karolina Kublickiene
- Renal Unit, Department of Clinical Sciences and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
| | - Peter Stenvinkel
- Renal Unit, Department of Clinical Sciences and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
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Di Paola R, De A, Izhar R, Abate M, Zappavigna S, Capasso A, Perna AF, La Russa A, Capasso G, Caraglia M, Simeoni M. Possible Effects of Uremic Toxins p-Cresol, Indoxyl Sulfate, p-Cresyl Sulfate on the Development and Progression of Colon Cancer in Patients with Chronic Renal Failure. Genes (Basel) 2023; 14:1257. [PMID: 37372437 DOI: 10.3390/genes14061257] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 06/09/2023] [Accepted: 06/10/2023] [Indexed: 06/29/2023] Open
Abstract
Chronic kidney disease (CKD) induces several systemic effects, including the accumulation and production of uremic toxins responsible for the activation of various harmful processes. Gut dysbiosis has been widely described in CKD patients, even in the early stages of the disease. The abundant discharge of urea and other waste substances into the gut favors the selection of an altered intestinal microbiota in CKD patients. The prevalence of bacteria with fermentative activity leads to the release and accumulation in the gut and in the blood of several substances, such as p-Cresol (p-C), Indoxyl Sulfate (IS) and p-Cresyl Sulfate (p-CS). Since these metabolites are normally eliminated in the urine, they tend to accumulate in the blood of CKD patients proportionally to renal impairment. P-CS, IS and p-C play a fundamental role in the activation of various pro-tumorigenic processes, such as chronic systemic inflammation, the increase in the production of free radicals and immune dysfunction. An up to two-fold increase in the incidence of colon cancer development in CKD has been reported in several studies, although the pathogenic mechanisms explaining this compelling association have not yet been described. Based on our literature review, it appears likely the hypothesis of a role of p-C, IS and p-CS in colon cancer development and progression in CKD patients.
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Affiliation(s)
- Rossella Di Paola
- Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Ananya De
- Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Raafiah Izhar
- Department of Mental and Physical Health and Preventive Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Marianna Abate
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Silvia Zappavigna
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Anna Capasso
- Department of Oncology, Livestrong Cancer Institutes, Dell Medical School, The University of Texas, Austin, TX 75063, USA
| | - Alessandra F Perna
- Nephrology and Dialysis Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", 80131 Naples, Italy
| | - Antonella La Russa
- Department of Sperimental Medical and Surgical Sciences, Magna Graecia University, 88100 Catanzaro, Italy
| | | | - Michele Caraglia
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
- Biogem S.c.a.r.l. Research Institute, 83031 Ariano Irpino, Italy
| | - Mariadelina Simeoni
- Nephrology and Dialysis Unit, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", 80131 Naples, Italy
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Mo Y, Hu D, Yu W, Ji C, Li Y, Liu X, Lu Z. Astragaloside IV attenuates indoxyl sulfate-induced injury of renal tubular epithelial cells by inhibiting the aryl hydrocarbon receptor pathway. JOURNAL OF ETHNOPHARMACOLOGY 2023; 308:116244. [PMID: 36764562 DOI: 10.1016/j.jep.2023.116244] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/17/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Astragalus membranaceus Fisch. ex Bunge has long been used to treat chronic kidney disease (CKD) in China. However, the mechanism of action requires further study. Indoxyl sulfate accumulation is the key cause of CKD progression. The aryl hydrocarbon receptor (AhR) plays an essential role in the renal tubular injury induced by indoxyl sulfate (IS). AIM We explored the effects of Astragaloside IV (AS-IV), a minor component of the flowering perennial Astragalus membranaceus Fisch. ex Bunge, on AhR activity during IS-induced injury of renal tubular epithelial cells. METHODS C57BL/6 mice fed a 0.2% adenine diet (adenine + IS) and intraperitoneally injected with IS were used to study the protective effects of AS-IV, and specifically the effect on the AhR. In addition, apoptosis (annexin/PI), oxidative stress and the AhR pathway were investigated in IS-stimulated HK-2 cells treated with AS-IV. The binding of AS-IV to the AhR was assessed in a molecular docking analysis. AhR knockdown using AhR siRNA allowed determination of the effects of AS-IV in IS-stimulated HK-2 cells. RESULTS AS-IV inhibited tubulointerstitial injury in adenine + IS mice. While AS-IV did not reduce serum IS levels, it did inhibit AhR expression in the kidney. In IS-stimulated HK-2 cells, AS-IV also dramatically reduced apoptosis, decreased oxidative stress responses and inhibited the expression of the AhR pathway. The molecular docking analysis showed surface binding of AS-IV to the AhR. Following AhR knockdown in HK-2 cells, IS-induced apoptosis was reduced and could not be further reduced by AS-IV. CONCLUSION By targeting the AhR, AS-IV may alleviate IS-induced renal tubular injury, thus offering a novel therapeutic approach to the treatment of chronic renal failure.
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Affiliation(s)
- Yenan Mo
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China; Nephrology Department, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Dongmei Hu
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Wanlin Yu
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Chunlan Ji
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yin Li
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China; Nephrology Department, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xusheng Liu
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China; Nephrology Department, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Zhaoyu Lu
- State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China; Nephrology Department, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
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8
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Microbial Tryptophan Metabolism Tunes Host Immunity, Metabolism, and Extraintestinal Disorders. Metabolites 2022; 12:metabo12090834. [PMID: 36144238 PMCID: PMC9505266 DOI: 10.3390/metabo12090834] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 08/29/2022] [Accepted: 08/31/2022] [Indexed: 11/17/2022] Open
Abstract
The trillions of commensal microorganisms comprising the gut microbiota have received growing attention owing to their impact on host physiology. Recent advances in our understandings of the host–microbiota crosstalk support a pivotal role of microbiota-derived metabolites in various physiological processes, as they serve as messengers in the complex dialogue between commensals and host immune and endocrine cells. In this review, we highlight the importance of tryptophan-derived metabolites in host physiology, and summarize the recent findings on the role of tryptophan catabolites in preserving intestinal homeostasis and fine-tuning immune and metabolic responses. Furthermore, we discuss the latest evidence on the effects of microbial tryptophan catabolites, describe their mechanisms of action, and discuss how perturbations of microbial tryptophan metabolism may affect the course of intestinal and extraintestinal disorders, including inflammatory bowel diseases, metabolic disorders, chronic kidney diseases, and cardiovascular diseases.
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Rahman MM, Islam F, -Or-Rashid MH, Mamun AA, Rahaman MS, Islam MM, Meem AFK, Sutradhar PR, Mitra S, Mimi AA, Emran TB, Fatimawali, Idroes R, Tallei TE, Ahmed M, Cavalu S. The Gut Microbiota (Microbiome) in Cardiovascular Disease and Its Therapeutic Regulation. Front Cell Infect Microbiol 2022; 12:903570. [PMID: 35795187 PMCID: PMC9251340 DOI: 10.3389/fcimb.2022.903570] [Citation(s) in RCA: 58] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/09/2022] [Indexed: 12/11/2022] Open
Abstract
In the last two decades, considerable interest has been shown in understanding the development of the gut microbiota and its internal and external effects on the intestine, as well as the risk factors for cardiovascular diseases (CVDs) such as metabolic syndrome. The intestinal microbiota plays a pivotal role in human health and disease. Recent studies revealed that the gut microbiota can affect the host body. CVDs are a leading cause of morbidity and mortality, and patients favor death over chronic kidney disease. For the function of gut microbiota in the host, molecules have to penetrate the intestinal epithelium or the surface cells of the host. Gut microbiota can utilize trimethylamine, N-oxide, short-chain fatty acids, and primary and secondary bile acid pathways. By affecting these living cells, the gut microbiota can cause heart failure, atherosclerosis, hypertension, myocardial fibrosis, myocardial infarction, and coronary artery disease. Previous studies of the gut microbiota and its relation to stroke pathogenesis and its consequences can provide new therapeutic prospects. This review highlights the interplay between the microbiota and its metabolites and addresses related interventions for the treatment of CVDs.
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El Chamieh C, Liabeuf S, Massy Z. Uremic Toxins and Cardiovascular Risk in Chronic Kidney Disease: What Have We Learned Recently beyond the Past Findings? Toxins (Basel) 2022; 14:toxins14040280. [PMID: 35448889 PMCID: PMC9028122 DOI: 10.3390/toxins14040280] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/10/2022] [Accepted: 04/11/2022] [Indexed: 12/13/2022] Open
Abstract
Patients with chronic kidney disease (CKD) have an elevated prevalence of atheromatous (ATH) and/or non-atheromatous (non-ATH) cardiovascular disease (CVD) due to an array of CKD-related risk factors, such as uremic toxins (UTs). Indeed, UTs have a major role in the emergence of a spectrum of CVDs, which constitute the leading cause of death in patients with end-stage renal disease. The European Uremic Toxin Work Group has identified over 100 UTs, more than 25 of which are dietary or gut-derived. Even though relationships between UTs and CVDs have been described in the literature, there are few reviews on the involvement of the most toxic compounds and the corresponding physiopathologic mechanisms. Here, we review the scientific literature on the dietary and gut-derived UTs with the greatest toxicity in vitro and in vivo. A better understanding of these toxins’ roles in the elevated prevalence of CVDs among CKD patients might facilitate the development of targeted treatments. Hence, we review (i) ATH and non-ATH CVDs and the respective levels of risk in patients with CKD and (ii) the mechanisms that underlie the influence of dietary and gut-derived UTs on CVDs.
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Affiliation(s)
- Carolla El Chamieh
- Center for Research in Epidemiology and Population Health (CESP), Paris-Saclay University, Versailles-Saint-Quentin-en-Yvelines University (UVSQ), INSERM UMRS 1018, F-94807 Villejuif, France;
| | - Sophie Liabeuf
- Pharmacology Department, Amiens University Hospital, F-80000 Amiens, France
- MP3CV Laboratory, EA7517, Jules Verne University of Picardie, F-80000 Amiens, France
- Correspondence: (S.L.); (Z.M.)
| | - Ziad Massy
- Nephrology Department, Ambroise Paré University Hospital, APHP, F-92100 Paris, France
- Correspondence: (S.L.); (Z.M.)
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11
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The Microbiome and Uremic Solutes. Toxins (Basel) 2022; 14:toxins14040245. [PMID: 35448854 PMCID: PMC9033124 DOI: 10.3390/toxins14040245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/07/2022] [Accepted: 03/23/2022] [Indexed: 02/05/2023] Open
Abstract
Uremic retention solutes, especially the protein-bound compounds, are toxic metabolites, difficult to eliminate with progressive renal functional decline. They are of particular interest because these uremic solutes are responsible for the pathogenesis of cardiovascular and chronic kidney diseases. Evidence suggests that the relation between uremic toxins, the microbiome, and its host is altered in patients with chronic kidney disease, with the colon’s motility, epithelial integrity, and absorptive properties also playing an important role. Studies found an alteration of the microbiota composition with differences in species proportion, diversity, and function. Since uremic toxins precursors are generated by the microbiota, multiple therapeutic options are currently being explored to address dysbiosis. While an oral adsorbent can decrease the transport of bacterial metabolites from the intestinal lumen to the blood, dietary measures, supplements (prebiotics, probiotics, and synbiotics), and antibiotics aim to target directly the gut microbiota composition. Innovative approaches, such as the modulation of bacterial enzymes, open new perspectives to decrease the plasma level of uremic toxins.
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12
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Uremic toxins activate CREB/ATF1 in endothelial cells related to chronic kidney disease. Biochem Pharmacol 2022; 198:114984. [PMID: 35245485 DOI: 10.1016/j.bcp.2022.114984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 11/22/2022]
Abstract
Uremic toxins, such as p-cresyl sulfate (PCS) and indoxyl sulfate (IS), contribute to endothelial dysfunction in chronic kidney disease (CKD). This process is mediated by several cellular pathways, but it is unclear whether cAMP-responsive element-binding protein (CREB) and activating transcription factor 1 (ATF1) participate in endothelial dysfunction in uremic conditions despite playing roles in inflammatory modulation. This study aimed to evaluate the expression, activation, and transcriptional activity of CREB/ATF1 in endothelial cells exposed to PCS, IS, and uremic serum (US). In vitro, ATF1 protein levels were increased by PCS and IS, whereas CREB levels were enhanced only by IS. Activation through CREB-Ser133 and ATF1-Ser63 phosphorylation was induced by PCS, IS, and US. We evaluated the CREB/ATF1 transcriptional activity by analyzing the expression of their target genes, including ICAM1, PTGS2, NOX1, and SLC22A6, which are related to endothelial dysfunction through their roles in vascular inflammation, oxidative stress, and cellular uptake of PCS and IS. The expression of ICAM1, PTGS2 and NOX1 genes was increased by PCS, IS, and US, whereas that of SLC22A6 was induced only by IS. KG-501, a CREB inhibitor, restored the inductive effects of PCS on ICAM1, PTGS2, and NOX1 expression; IS on ICAM1, PTGS2 and SLC22A6 expression; and US on NOX1 expression. The presence of CREB and ATF1 was observed in healthy arteries and in arteries of patients with CKD, which were structurally damaged. These findings suggest that CREB/ATF1 is activated by uremic toxins and may play a relevant role in endothelial dysfunction in CKD.
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13
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Serum concentrations of free indoxyl and p-cresyl sulfate are associated with mineral metabolism variables and cardiovascular risk in hemodialysis patients. J Nephrol 2022; 35:1457-1465. [PMID: 35175580 DOI: 10.1007/s40620-022-01271-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/01/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND Indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are uremic toxins associated with cardiovascular outcome in CKD patients. The present work is an analysis of the association of serum free, total IS and PCS with cardiovascular events and calcium-phosphate metabolism variables in hemodialysis patients. METHODS Serum levels of total and free IS and PCS were measured in 139 hemodialysis patients. Their relationship with calcium-phosphate metabolism variables were tested in an observational cohort study. In addition, their association with cardiovascular events was investigated during a 4-year follow-up. RESULTS Patients in the highest tertile (T3) of serum free IS showed lower serum 1,25(OH)2D compared to patients in the middle (T2) and lowest tertile (T1); in addition to this, T3 patients showed lower serum irisin than T1 patients and lower serum PTH than all the other subjects (T1 + T2) combined. Serum PTH was also measured during the two years after the baseline measurement and was higher in patients in the T1 than in those in the T3 of serum free IS. Cox regression analysis showed that cardiovascular risk was lower in T1 patients than in those in the T3 of serum free PCS, both using a univariate (OR 2.55, 95% CI 1.2-5.43; p = 0.015) or multivariate model (OR 2.48, 95% CI 1.12-5.51; p = 0.003). CONCLUSIONS Serum free IS may be associated with PTH and 1,25(OH)2D secretion, whereas free PCS may predict cardiovascular risk in hemodialysis patients.
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14
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Yan Z, Wang G, Shi X. Advances in the Progression and Prognosis Biomarkers of Chronic Kidney Disease. Front Pharmacol 2022; 12:785375. [PMID: 34992536 PMCID: PMC8724575 DOI: 10.3389/fphar.2021.785375] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/30/2021] [Indexed: 12/29/2022] Open
Abstract
Chronic kidney disease (CKD) is one of the increasingly serious public health concerns worldwide; the global burden of CKD is increasingly due to high morbidity and mortality. At present, there are three key problems in the clinical treatment and management of CKD. First, the current diagnostic indicators, such as proteinuria and serum creatinine, are greatly interfered by the physiological conditions of patients, and the changes in the indicator level are not synchronized with renal damage. Second, the established diagnosis of suspected CKD still depends on biopsy, which is not suitable for contraindication patients, is also traumatic, and is not sensitive to early progression. Finally, the prognosis of CKD is affected by many factors; hence, it is ineviatble to develop effective biomarkers to predict CKD prognosis and improve the prognosis through early intervention. Accurate progression monitoring and prognosis improvement of CKD are extremely significant for improving the clinical treatment and management of CKD and reducing the social burden. Therefore, biomarkers reported in recent years, which could play important roles in accurate progression monitoring and prognosis improvement of CKD, were concluded and highlighted in this review article that aims to provide a reference for both the construction of CKD precision therapy system and the pharmaceutical research and development.
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Affiliation(s)
- Zhonghong Yan
- Heilongjiang University of Chinese Medicine, Harbin, China
| | - Guanran Wang
- Heilongjiang University of Chinese Medicine, Harbin, China.,Department of Nephrology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Xingyang Shi
- Heilongjiang University of Chinese Medicine, Harbin, China
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15
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Alam MJ, Puppala V, Uppulapu SK, Das B, Banerjee SK. Human microbiome and cardiovascular diseases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 192:231-279. [DOI: 10.1016/bs.pmbts.2022.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Di Pierro F. A Possible Perspective about the Compositional Models, Evolution, and Clinical Meaning of Human Enterotypes. Microorganisms 2021; 9:microorganisms9112341. [PMID: 34835466 PMCID: PMC8618122 DOI: 10.3390/microorganisms9112341] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 01/19/2023] Open
Abstract
Among the various parameters obtainable through the analysis of the human gut microbiota, the enterotype is one of the first classifications of the bacterial consortia, which tried to obtain, at the same time, as much information as possible to be applied in clinical medicine. Although some authors observed the existence not of clusters, but only of a real continuous gradient, enterotypes are commonly described according to various models. The first model predicted either clustering into enterotypes 1 and 2 based on two specific dominances, Bacteroides and Prevotella, respectively, with the Ruminococcus dominance blurred within the Bacteroides dominance, or it predicted a threedominant condition, in which the Ruminococcus driver constituted enterotype 3, separated from enterotype 1. A second model envisaged three possible ways to cluster gut microbiota, respectively centred on two, three, and four dominances. In the first case, enterotypes 1 and 2 coincided with the two original enterotypes, with the dominance of Bacteroides and Prevotella, respectively. In the second case, the existence of enterotype 3 was evident and whose dominance was not centred on Ruminococcus but extended more towards the entire Firmicutes phylum. In the third case, the presence of the phylum Firmicutes was split into two different enterotypes generating the clusters defined and named as Mixtures 1 and 2. Subsequently, the analysis of the water content (hydration) in the stool allowed the splitting of the Bacteroides enterotype into two sub-enterotype, respectively known as B1 and B2. All these models have allowed us to highlight some correlations between a specific enterotype, or cluster, and some characteristics, such as the greater predisposition of the respective hosts towards certain pathologies. These observations, coupled with the attempt to derive the different microbiota on an evolutionary basis, can help to shed new light on this topic and demonstrate the possible utility that the different ways of clustering the gut microbiota can have in a clinical application perspective and in preventive medicine.
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Affiliation(s)
- Francesco Di Pierro
- Digestive Endoscopy & Gastroenterology, Fondazione Poliambulanza, 25124 Brescia, Italy;
- UNICAM, Camerino University, 62032 Camerino, Italy
- Scientific Department, Velleja Research, 20124 Milan, Italy
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17
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Reichard CA, Naelitz BD, Wang Z, Jia X, Li J, Stampfer MJ, Klein EA, Hazen SL, Sharifi N. Gut Microbiome-Dependent Metabolic Pathways and Risk of Lethal Prostate Cancer: Prospective Analysis of a PLCO Cancer Screening Trial Cohort. Cancer Epidemiol Biomarkers Prev 2021; 31:192-199. [PMID: 34711629 DOI: 10.1158/1055-9965.epi-21-0766] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/01/2021] [Accepted: 10/05/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Diet and the gut microbiome have a complex interaction that generates metabolites with an unclear effect on lethal prostate cancer risk. Identification of modifiable risk factors for lethal prostate cancer is challenging given the long natural history of this disease and difficulty of prospectively identifying lethal cancers. METHODS Mass spectrometry was performed on baseline serum samples collected from 173 lethal prostate cancer cases and 519 controls enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening trial. Baseline serum levels of choline, carnitine, betaine, γ-butyrobetaine, crotonobetaine, phenylacetylglutamine, hippuric acid, and p-cresol sulfate were quantified and analyzed by quartile. Conditional multivariable logistic regression analysis associated analyte levels with lethal prostate cancer incidence after adjusting for body mass index and PSA. The Cochran-Armitage test evaluated analyte level trends across quartiles. RESULTS Relative to those in the first quartile, cases with the highest baseline levels of choline (Q4 OR: 2.19; 95% CI, 1.23-3.90; P-trend: 0.005) and betaine (Q4 OR: 1.86; 95% CI, 1.05-3.30; P-trend: 0.11) exhibited increased odds of developing lethal prostate cancer. Higher baseline serum levels of phenylacetylglutamine (Q4 OR: 2.55; 95% CI, 1.40-4.64; P-trend: 0.003), a gut microbiome metabolite of phenylalanine with adrenergic activity, were also associated with lethal prostate cancer. CONCLUSIONS Baseline serum levels of one-carbon methyl donors and adrenergic compounds resulting from human and gut microbiota-mediated metabolism are associated with increased lethal prostate cancer risk. IMPACT Dietary composition, circulating metabolite levels, and downstream signaling pathways may represent modifiable risk factors associated with incident lethal prostate cancer. Beta-adrenergic blockade represents an additional target for oncologic risk reduction.
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Affiliation(s)
- Chad A Reichard
- Genitourinary Malignancies Research Center, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.,Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.,Urology of Indiana, Indianapolis, Indiana
| | - Bryan D Naelitz
- Genitourinary Malignancies Research Center, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.,Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio
| | - Zeneng Wang
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland Ohio
| | - Xun Jia
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland Ohio
| | - Jianbo Li
- Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.,Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
| | - Meir J Stampfer
- Departments of Epidemiology and Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.,Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Eric A Klein
- Genitourinary Malignancies Research Center, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.,Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.,Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio
| | - Stanley L Hazen
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland Ohio.,Department of Cardiovascular Medicine, Heart, Vascular and Thoracic Institute, Cleveland Clinic, Cleveland Ohio
| | - Nima Sharifi
- Genitourinary Malignancies Research Center, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio. .,Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.,Taussig Cancer Institute, Cleveland Clinic, Cleveland, Ohio
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18
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Melekoglu E, Samur FG. Dietary strategies for gut-derived protein-bound uremic toxins and cardio-metabolic risk factors in chronic kidney disease: A focus on dietary fibers. Crit Rev Food Sci Nutr 2021:1-15. [PMID: 34704501 DOI: 10.1080/10408398.2021.1996331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Chronic kidney disease (CKD) is associated with altered composition and function of gut microbiota. The cause of gut dysbiosis in CKD is multifactorial and encompasses the following: uremic state, metabolic acidosis, slow colonic transit, dietary restrictions of plant-based fiber-rich foods, and pharmacological therapies. Dietary restriction of potassium-rich fruits and vegetables, which are common sources of fermentable dietary fibers, inhibits the conversion of dietary fibers to short-chain fatty acids (SCFA), which are the primary nutrient source for the symbiotic gut microbiota. Reduced consumption of fermentable dietary fibers limits the population of SCFA-forming bacteria and causes dysbiosis of gut microbiota. Gut dysbiosis induces colonic fermentation of protein and formation of gut-derived uremic toxins. In this review, we discuss the roles and benefits of dietary fiber on gut-derived protein-bound uremic toxins and plant-based dietary patterns that could be recommended to decrease uremic toxin formation in CKD patients. Recent studies have indicated that dietary fiber supplementation may be useful to decrease gut-derived uremic toxin formation and slow CKD progression. However, research on associations between adherence of healthy dietary patterns and gut-derived uremic toxins formation in patients with CKD is lacking.
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Affiliation(s)
- Ebru Melekoglu
- Faculty of Health Sciences, Nutrition and Dietetics Department, Hacettepe University, Ankara, Turkey.,Faculty of Health Sciences, Nutrition and Dietetics Department, Cukurova University, Adana, Turkey
| | - F Gulhan Samur
- Faculty of Health Sciences, Nutrition and Dietetics Department, Hacettepe University, Ankara, Turkey
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19
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Liao HY, Wang CY, Lee CH, Kao HL, Wu WK, Kuo CH. Development of an Efficient and Sensitive Chemical Derivatization-Based LC-MS/MS Method for Quantifying Gut Microbiota-Derived Metabolites in Human Plasma and Its Application in Studying Cardiovascular Disease. J Proteome Res 2021; 20:3508-3518. [PMID: 34053222 DOI: 10.1021/acs.jproteome.1c00147] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recently, the gut microbiota has been found to be associated with many diseases, such as inflammatory bowel disease, depression, Parkinson's disease, cancer, metabolic syndrome, and cardiovascular disease (CVD). Among various gut microbiota-derived metabolites (GMs), short-chain fatty acids (SCFAs), bile acids (BAs), and tryptophan (TRP) metabolites are the most frequently discussed metabolites. LC-MS/MS shows advantages in quantifying the levels of metabolites with good sensitivity and selectivity; however, the poor ionization efficiency and polar characteristics of SCFAs make their analysis challenging, especially when analyzing plasma samples with low SCFA concentrations. Moreover, without characteristic fragment ions for unconjugated BAs and different detection ion modes for TRP metabolites and BAs, GM analysis is complex and time-consuming. To overcome these problems, we developed a derivatization method combined with LC-MS/MS to enhance the sensitivity and LC retention of GMs. Through derivatization with 3-nitrophenylhydrazine (3-NPH), 7 SCFAs, 9 bile acids, and 6 tryptophan metabolites can be simultaneously analyzed via separation within 14 min on a reversed-phase C18 column. For accurate quantification, 13C6-3NPH-labeled standards were used as one-to-one internal standards. This derivatization approach was optimized and then validated. We further applied this method to investigate the targeted GM profile in patients with CVD. The results showed a significant reduction in plasma butyrate levels in CVD patients compared with healthy controls, suggesting its potentially protective role in CVD. In summary, this work provides a sensitive and effective LC-MS/MS method for simultaneously quantifying gut microbiota-related metabolites in human plasma, which could benefit various future gut microbiota-related studies.
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Affiliation(s)
- Hsin-Yu Liao
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.,Department of Pharmacy, National Taiwan University Hospital, Taipei 10051, Taiwan
| | - Chin-Yi Wang
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.,Department of Pharmacy, National Taiwan University Hospital, Taipei 10051, Taiwan
| | - Ching-Hua Lee
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.,Department of Pharmacy, National Taiwan University Hospital, Taipei 10051, Taiwan
| | - Hsien-Li Kao
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei 10048, Taiwan
| | - Wei-Kai Wu
- Department of Medical Research, National Taiwan University Hospital, Taipei 10048, Taiwan
| | - Ching-Hua Kuo
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.,The Metabolomics Core Laboratory, Centers of Genomic and Precision Medicine, National Taiwan University, Taipei 10055, Taiwan.,Department of Pharmacy, National Taiwan University Hospital, Taipei 10051, Taiwan
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20
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Bhatraju PK, Chai XY, Sathe NA, Ruzinski J, Siew ED, Himmelfarb J, Hoofnagle AN, Wurfel MM, Kestenbaum BR. Assessment of kidney proximal tubular secretion in critical illness. JCI Insight 2021; 6:145514. [PMID: 33886506 PMCID: PMC8262320 DOI: 10.1172/jci.insight.145514] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 04/21/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUNDSerum creatinine concentrations (SCrs) are used to determine the presence and severity of acute kidney injury (AKI). SCr is primarily eliminated by glomerular filtration; however, most mechanisms of AKI in critical illness involve kidney proximal tubules, where tubular secretion occurs. Proximal tubular secretory clearance is not currently estimated in the intensive care unit (ICU). Our objective was to estimate the kidney clearance of secretory solutes in critically ill adults.METHODSWe collected matched blood and spot urine samples from 170 ICU patients and from a comparison group of 70 adults with normal kidney function. We measured 7 endogenously produced secretory solutes using liquid chromatography-tandem mass spectrometry. We computed a composite secretion score incorporating all 7 solutes and evaluated associations with 28-day major adverse kidney events (MAKE28), defined as doubling of SCr, dialysis dependence, or death.RESULTSThe urine-to-plasma ratios of 6 of 7 secretory solutes were lower in critically ill patients compared with healthy individuals after adjustment for SCr. The composite secretion score was moderately correlated with SCr and cystatin C (r = -0.51 and r = -0.53, respectively). Each SD higher composite secretion score was associated with a 25% lower risk of MAKE28 (95% CI 9% to 38% lower) independent of severity of illness, SCr, and tubular injury markers. Higher urine-to-plasma ratios of individual secretory solutes isovalerylglycine and tiglylglycine were associated with MAKE28 after accounting for multiple testing.CONCLUSIONAmong critically ill adults, tubular secretory clearance is associated with adverse outcomes, and its measurement could improve assessment of kidney function and dosing of essential ICU medications.FUNDINGGrants from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK/NIH) K23DK116967, the University of Washington Diabetes Research Center P30DK017047, an unrestricted gift to the Kidney Research Institute from the Northwest Kidney Centers, and the Vanderbilt O'Brien Kidney Center (NIDDK 5P30 DK114809-03). The funding sources had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.
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Affiliation(s)
- Pavan K Bhatraju
- Division of Pulmonary, Critical Care and Sleep Medicine and.,Kidney Research Institute, Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Xin-Ya Chai
- Division of Pulmonary, Critical Care and Sleep Medicine and
| | - Neha A Sathe
- Division of Pulmonary, Critical Care and Sleep Medicine and
| | - John Ruzinski
- Kidney Research Institute, Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Edward D Siew
- Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Vanderbilt Integrated Program for AKI, Nashville, Tennessee, USA.,Tennessee Valley Health Services, Nashville VA Medical Center, Nashville, Tennessee, USA
| | - Jonathan Himmelfarb
- Kidney Research Institute, Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Andrew N Hoofnagle
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - Mark M Wurfel
- Division of Pulmonary, Critical Care and Sleep Medicine and
| | - Bryan R Kestenbaum
- Kidney Research Institute, Division of Nephrology, Department of Medicine, University of Washington, Seattle, Washington, USA
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21
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Mosterd CM, Kanbay M, van den Born BJH, van Raalte DH, Rampanelli E. Intestinal microbiota and diabetic kidney diseases: the Role of microbiota and derived metabolites inmodulation of renal inflammation and disease progression. Best Pract Res Clin Endocrinol Metab 2021; 35:101484. [PMID: 33546983 DOI: 10.1016/j.beem.2021.101484] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Diabetic kidney disease (DKD) represents a growing public health burden and is the leading cause of end-stage kidney diseases. In recent years, host-gut microbiota interactions have emerged as an integral part for host homeostasis. In the context of nephropathies, mounting evidence supports a bidirectional microbiota-kidney crosstalk, which becomes particularly manifest during progressive kidney dysfunction. Indeed, in chronic kidney disease (CKD), the "healthy" microbiota structure is disrupted and intestinal microbes produce large quantities of uremic solutes responsible for renal damage; on the other hand, the uremic state, fueled by reduced renal clearance, causes shifts in microbial metabolism and composition, hence creating a vicious cycle in which dysbiosis and renal dysfunction are progressively worsened. In this review, we will summarize the evidence from clinical/experimental studies concerning the occurrence of gut dysbiosis in diabetic and non-diabetic CKD, discuss the functional consequences of dysbiosis for CKD progression and debate putative therapeutic interventions targeting the intestinal microbiome.
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Affiliation(s)
- C M Mosterd
- Department of Internal and Vascular Medicine, Amsterdam UMC, Location VUmc, Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands.
| | - M Kanbay
- Department of Medicine, Division of Nephrology, Koc University School of Medicine, Istanbul, Turkey
| | - B J H van den Born
- Department of Nephrology and Vascular Medicine, Amsterdam UMC, Location AMC, the Netherlands
| | - D H van Raalte
- Diabetes Center, Department of Internal Medicine, Amsterdam UMC, Location VUmc, Diabetes Center, Amsterdam, the Netherlands
| | - E Rampanelli
- Department of Experimental Vascular Medicine, Amsterdam UMC, Location AMC, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam, the Netherlands.
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22
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El Amouri A, Snauwaert E, Foulon A, Vande Moortel C, Van Dyck M, Van Hoeck K, Godefroid N, Glorieux G, Van Biesen W, Vande Walle J, Raes A, Eloot S. Dietary Fibre Intake Is Associated with Serum Levels of Uraemic Toxins in Children with Chronic Kidney Disease. Toxins (Basel) 2021; 13:toxins13030225. [PMID: 33808581 PMCID: PMC8003569 DOI: 10.3390/toxins13030225] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/13/2021] [Accepted: 03/17/2021] [Indexed: 12/11/2022] Open
Abstract
Imbalanced colonic microbial metabolism plays a pivotal role in generating protein-bound uraemic toxins (PBUTs), which accumulate with deteriorating kidney function and contribute to the uraemic burden of children with chronic kidney disease (CKD). Dietary choices impact the gut microbiome and metabolism. The aim of this study was to investigate the relation between dietary fibre and gut-derived PBUTs in paediatric CKD. Sixty-one (44 male) CKD children (9 ± 5 years) were prospectively followed for two years. Dietary fibre intake was evaluated by either 24-h recalls (73%) or 3-day food records (27%) at the same time of blood sampling for assessment of total and free serum levels of different PBUTs using liquid chromatography. We used linear mixed models to assess associations between fibre intake and PBUT levels. We found an inverse association between increase in fibre consumption (g/day) and serum concentrations of free indoxyl sulfate (−3.1% (−5.9%; −0.3%) (p = 0.035)), free p-cresyl sulfate (−2.5% (−4.7%; −0.3%) (p = 0.034)), total indole acetic acid (IAA) (−1.6% (−3.0%; −0.3%) (p = 0.020)), free IAA (−6.6% (−9.3%; −3.7%) (p < 0.001)), total serum p-cresyl glucuronide (pCG) (−3.0% (−5.6%; −0.5%) (p = 0.021)) and free pCG levels (−3.3% (−5.8%; −0.8%) (p = 0.010)). The observed associations between dietary fibre intake and the investigated PBUTs highlight potential benefits of fibre intake for the paediatric CKD population. The present observational findings should inform and guide adaptations of dietary prescriptions in children with CKD.
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Affiliation(s)
- Amina El Amouri
- Paediatric Nephrology and Rheumatology Section, Department of Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (E.S.); (J.V.W.); (A.R.)
- Correspondence:
| | - Evelien Snauwaert
- Paediatric Nephrology and Rheumatology Section, Department of Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (E.S.); (J.V.W.); (A.R.)
| | - Aurélie Foulon
- Nephrology Section, Department of Internal Medicine and Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (A.F.); (C.V.M.); (G.G.); (W.V.B.); (S.E.)
| | - Charlotte Vande Moortel
- Nephrology Section, Department of Internal Medicine and Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (A.F.); (C.V.M.); (G.G.); (W.V.B.); (S.E.)
| | - Maria Van Dyck
- Paediatric Nephrology Section, Department of Paediatrics, University Hospitals Leuven (Campus Gasthuisberg), Herestraat 49, 3000 Leuven, Belgium;
| | - Koen Van Hoeck
- Paediatric Nephrology Section, Department of Paediatrics, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium;
| | - Nathalie Godefroid
- Paediatric Nephrology Section, Department of Paediatrics, Cliniques Universitaires St. Luc, Université Catholique Louvain, Avenue Hippocrate 10, 1200 Brussels, Belgium;
| | - Griet Glorieux
- Nephrology Section, Department of Internal Medicine and Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (A.F.); (C.V.M.); (G.G.); (W.V.B.); (S.E.)
| | - Wim Van Biesen
- Nephrology Section, Department of Internal Medicine and Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (A.F.); (C.V.M.); (G.G.); (W.V.B.); (S.E.)
| | - Johan Vande Walle
- Paediatric Nephrology and Rheumatology Section, Department of Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (E.S.); (J.V.W.); (A.R.)
| | - Ann Raes
- Paediatric Nephrology and Rheumatology Section, Department of Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (E.S.); (J.V.W.); (A.R.)
| | - Sunny Eloot
- Nephrology Section, Department of Internal Medicine and Paediatrics, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium; (A.F.); (C.V.M.); (G.G.); (W.V.B.); (S.E.)
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Challenges of reducing protein-bound uremic toxin levels in chronic kidney disease and end stage renal disease. Transl Res 2021; 229:115-134. [PMID: 32891787 DOI: 10.1016/j.trsl.2020.09.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/24/2020] [Accepted: 09/02/2020] [Indexed: 12/11/2022]
Abstract
The prevalence of chronic kidney disease (CKD) in the worldwide population is currently estimated between 11% and 13%. Adequate renal clearance is compromised in these patients and the accumulation of a large number of uremic retention solutes results in an irreversible worsening of renal function which can lead to end stage renal disease (ESRD). Approximately three million ESRD patients currently receive renal replacement therapies (RRTs), such as hemodialysis, which only partially restore kidney function, as they are only efficient in removing mainly small, unbound solutes from the circulation while leaving larger and protein-bound uremic toxins (PBUTs) untouched. The accumulation of PBUTs in patients highly increases the risk of cardiovascular events and is associated with higher mortality and morbidity in CKD and ESRD. In this review, we address several strategies currently being explored toward reducing PBUT concentrations, including clinical and medical approaches, therapeutic techniques, and recent developments in RRT technology. These include preservation of renal function, limitation of colon derived PBUTs, oral sorbents, adsorbent RRT technology, and use of albumin displacers. Despite the promising results of the different approaches to promote enhanced removal of a small percentage of the more than 30 identified PBUTs, on their own, none of them provide a treatment with the required efficiency, safety and cost-effectiveness to prevent CKD-related complications and decrease mortality and morbidity in ESRD.
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de Andrade LS, Sardá FAH, Pereira NBF, Teixeira RR, Rodrigues SD, de Lima JD, Dalboni MA, Aoike DT, Nakao LS, Cuppari L. Effect of Unripe Banana Flour on Gut-Derived Uremic Toxins in Individuals Undergoing Peritoneal Dialysis: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial. Nutrients 2021; 13:nu13020646. [PMID: 33671166 PMCID: PMC7922008 DOI: 10.3390/nu13020646] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/05/2021] [Accepted: 02/10/2021] [Indexed: 12/23/2022] Open
Abstract
In chronic kidney disease (CKD), the accumulation of gut-derived metabolites, such as indoxyl sulfate (IS), p-cresyl sulfate (pCS), and indole 3-acetic acid (IAA), has been associated with the burden of the disease. In this context, prebiotics emerge as a strategy to mitigate the accumulation of such compounds, by modulating the gut microbiota and production of their metabolites. The aim of this study was to evaluate the effect of unripe banana flour (UBF-48% resistant starch, a prebiotic) on serum concentrations of IS, pCS, and IAA in individuals undergoing peritoneal dialysis (PD). A randomized, double-blind, placebo-controlled, crossover trial was conducted. Forty-three individuals on PD were randomized to sequential treatment with UBF (21 g/day) and placebo (waxy corn starch-12 g/day) for 4 weeks, or vice versa (4-week washout). The primary outcomes were total and free serum levels of IS, pCS, and IAA. Secondary outcomes were 24 h urine excretion and dialysis removal of IS, pCS, and IAA, serum inflammatory markers [high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α)], serum lipopolysaccharide LPS, and dietary intake. Of the 43 individuals randomized, 26 completed the follow-up (age = 55 ± 12 years; 53.8% men). UBF did not promote changes in serum levels of IS (p = 0.70), pCS (p = 0.70), and IAA (p = 0.74). Total serum IS reduction was observed in a subgroup of participants (n = 11; placebo: median 79.5 μmol/L (31-142) versus UBF: 62.5 μmol/L (31-133), p = 0.009) who had a daily UBF intake closer to that proposed in the study. No changes were observed in other secondary outcomes. UBF did not promote changes in serum levels of IS or pCS and IAA; a decrease in IS was only found in the subgroup of participants who were able to take 21g/day of the UBF.
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Affiliation(s)
- Laila Santos de Andrade
- Nutrition Program, Universidade Federal de São Paulo—UNIFESP, São Paulo 05508-000, Brazil; (L.S.d.A.); (N.B.F.P.); (R.R.T.)
| | - Fabiana Andréa Hoffmann Sardá
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, Universidade de São Paulo—USP, São Paulo 05508-000, Brazil;
- APC Microbiome Ireland, University College Cork, Cork T12 K8AF, Ireland
| | | | - Renata Rodrigues Teixeira
- Nutrition Program, Universidade Federal de São Paulo—UNIFESP, São Paulo 05508-000, Brazil; (L.S.d.A.); (N.B.F.P.); (R.R.T.)
| | - Silvia Daniéle Rodrigues
- Department of Basic Pathology, Universidade Federal do Paraná—UFPR, Curitiba 81531-980, Brazil; (S.D.R.); (L.S.N.)
| | - Jordana Dinorá de Lima
- Department of Cell Biology, Universidade Federal do Paraná—UFPR, Curitiba 81531-980, Brazil;
| | - Maria Aparecida Dalboni
- Post-Graduate Program in Medicine, Universidade Nove de Julho—UNINOVE, São Paulo 01504-001, Brazil;
| | - Danilo Takashi Aoike
- Division of Nephrology, Universidade Federal de São Paulo—UNIFESP, Rua Botucatu, 720/740, São Paulo 04023-062, Brazil;
| | - Lia Sumie Nakao
- Department of Basic Pathology, Universidade Federal do Paraná—UFPR, Curitiba 81531-980, Brazil; (S.D.R.); (L.S.N.)
| | - Lilian Cuppari
- Nutrition Program, Universidade Federal de São Paulo—UNIFESP, São Paulo 05508-000, Brazil; (L.S.d.A.); (N.B.F.P.); (R.R.T.)
- Division of Nephrology, Universidade Federal de São Paulo—UNIFESP, Rua Botucatu, 720/740, São Paulo 04023-062, Brazil;
- Dialysis Department, Hospital do Rim—Fundação Oswaldo Ramos, São Paulo 04038-002, Brazil
- Correspondence: ; Tel.: +55-11-99125-5848
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Nagata D, Yoshizawa H. Pharmacological Actions of Indoxyl Sulfate and AST-120 That Should Be Recognized for the Strategic Treatment of Patients with Chronic Kidney Disease. Int J Nephrol Renovasc Dis 2020; 13:359-365. [PMID: 33311993 PMCID: PMC7726832 DOI: 10.2147/ijnrd.s287237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 11/17/2020] [Indexed: 11/30/2022] Open
Abstract
Although there are many uremic substances in the body, the most studied and well-known molecule that predominantly binds to plasma proteins is indoxyl sulfate (IS). Many research groups have reported IS to have toxic effects on the kidney and cardiovascular system. It is difficult to remove IS with regular hemodialysis or hemodiafiltration. On the other hand, AST-120 has the capacity to bind to indole, which is a precursor of IS in the intestinal tract and excrete it in feces. IS production in the liver is efficiently suppressed by AST-120 administration. However, large-scale clinical studies have not shown that AST-120 suppresses hard endpoints such as doubling serum creatinine, end-stage renal disease, and death. In patients with accelerated chronic kidney disease (CKD) progression, AST-120 is expected to suppress those hard renal endpoints, but only when compliance to treatment is high. It is necessary to validate the renal protective effect of AST-120, as expected from the basic study on IS, including more patients with slowly progressive CKD in a large-scale clinical study in the future.
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Affiliation(s)
- Daisuke Nagata
- Division of Nephrology, Department of Internal Medicine, Jichi Medical University, Tochigi, Japan
| | - Hiromichi Yoshizawa
- Division of Nephrology, Department of Internal Medicine, Jichi Medical University, Tochigi, Japan
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Nayor M, Shah RV, Miller PE, Blodgett JB, Tanguay M, Pico AR, Murthy VL, Malhotra R, Houstis NE, Deik A, Pierce KA, Bullock K, Dailey L, Velagaleti RS, Moore SA, Ho JE, Baggish AL, Clish CB, Larson MG, Vasan RS, Lewis GD. Metabolic Architecture of Acute Exercise Response in Middle-Aged Adults in the Community. Circulation 2020; 142:1905-1924. [PMID: 32927962 PMCID: PMC8049528 DOI: 10.1161/circulationaha.120.050281] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Whereas regular exercise is associated with lower risk of cardiovascular disease and mortality, mechanisms of exercise-mediated health benefits remain less clear. We used metabolite profiling before and after acute exercise to delineate the metabolic architecture of exercise response patterns in humans. METHODS Cardiopulmonary exercise testing and metabolite profiling was performed on Framingham Heart Study participants (age 53±8 years, 63% women) with blood drawn at rest (n=471) and at peak exercise (n=411). RESULTS We observed changes in circulating levels for 502 of 588 measured metabolites from rest to peak exercise (exercise duration 11.9±2.1 minutes) at a 5% false discovery rate. Changes included reductions in metabolites implicated in insulin resistance (glutamate, -29%; P=1.5×10-55; dimethylguanidino valeric acid [DMGV], -18%; P=5.8×10-18) and increases in metabolites associated with lipolysis (1-methylnicotinamide, +33%; P=6.1×10-67), nitric oxide bioavailability (arginine/ornithine + citrulline, +29%; P=2.8×10-169), and adipose browning (12,13-dihydroxy-9Z-octadecenoic acid +26%; P=7.4×10-38), among other pathways relevant to cardiometabolic risk. We assayed 177 metabolites in a separate Framingham Heart Study replication sample (n=783, age 54±8 years, 51% women) and observed concordant changes in 164 metabolites (92.6%) at 5% false discovery rate. Exercise-induced metabolite changes were variably related to the amount of exercise performed (peak workload), sex, and body mass index. There was attenuation of favorable excursions in some metabolites in individuals with higher body mass index and greater excursions in select cardioprotective metabolites in women despite less exercise performed. Distinct preexercise metabolite levels were associated with different physiologic dimensions of fitness (eg, ventilatory efficiency, exercise blood pressure, peak Vo2). We identified 4 metabolite signatures of exercise response patterns that were then analyzed in a separate cohort (Framingham Offspring Study; n=2045, age 55±10 years, 51% women), 2 of which were associated with overall mortality over median follow-up of 23.1 years (P≤0.003 for both). CONCLUSIONS In a large sample of community-dwelling individuals, acute exercise elicits widespread changes in the circulating metabolome. Metabolic changes identify pathways central to cardiometabolic health, cardiovascular disease, and long-term outcome. These findings provide a detailed map of the metabolic response to acute exercise in humans and identify potential mechanisms responsible for the beneficial cardiometabolic effects of exercise for future study.
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Affiliation(s)
- Matthew Nayor
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Ravi V. Shah
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Patricia E. Miller
- Department of Biostatistics, Boston University School of Public Health, Boston, MA
| | - Jasmine B. Blodgett
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Melissa Tanguay
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Alexander R. Pico
- Institute of Data Science and Biotechnology, Gladstone Institutes, San Francisco, CA
| | - Venkatesh L. Murthy
- Division of Cardiovascular Medicine, Department of Medicine, University of Michigan, Ann Arbor
- Frankel Cardiovascular Center, University of Michigan, Ann Arbor
| | - Rajeev Malhotra
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA
| | - Nicholas E. Houstis
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Amy Deik
- Broad Institute of MIT and Harvard, Cambridge, MA
| | | | | | - Lucas Dailey
- Broad Institute of MIT and Harvard, Cambridge, MA
| | - Raghava S. Velagaleti
- Cardiology Section, Department of Medicine, Boston VA Healthcare System, West Roxbury, MA
| | - Stephanie A. Moore
- Cardiology Section, Department of Medicine, Boston VA Healthcare System, West Roxbury, MA
| | - Jennifer E. Ho
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Aaron L. Baggish
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | | - Martin G. Larson
- Department of Biostatistics, Boston University School of Public Health, Boston, MA
- Boston University’s and National Heart, Lung, and Blood Institute’s Framingham Heart Study, Framingham, MA
| | - Ramachandran S. Vasan
- Boston University’s and National Heart, Lung, and Blood Institute’s Framingham Heart Study, Framingham, MA
- Sections of Preventive Medicine and Epidemiology, and Cardiology, Department of Medicine, Boston University School of Medicine, Boston, MA
| | - Gregory D. Lewis
- Cardiology Division and the Simches Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA
- Pulmonary Critical Care Unit, Massachusetts General Hospital, Boston, MA
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Søndertoft NB, Vogt JK, Arumugam M, Kristensen M, Gøbel RJ, Fan Y, Lyu L, Bahl MI, Eriksen C, Ängquist L, Frøkiær H, Hansen TH, Brix S, Nielsen HB, Hansen T, Vestergaard H, Gupta R, Licht TR, Lauritzen L, Pedersen O. The intestinal microbiome is a co-determinant of the postprandial plasma glucose response. PLoS One 2020; 15:e0238648. [PMID: 32947608 PMCID: PMC7500969 DOI: 10.1371/journal.pone.0238648] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 08/20/2020] [Indexed: 12/15/2022] Open
Abstract
Elevated postprandial plasma glucose is a risk factor for development of type 2 diabetes and cardiovascular disease. We hypothesized that the inter-individual postprandial plasma glucose response varies partly depending on the intestinal microbiome composition and function. We analyzed data from Danish adults (n = 106), who were self-reported healthy and attended the baseline visit of two previously reported randomized controlled cross-over trials within the Gut, Grain and Greens project. Plasma glucose concentrations at five time points were measured before and during three hours after a standardized breakfast. Based on these data, we devised machine learning algorithms integrating bio-clinical, as well as shotgun-sequencing-derived taxa and functional potentials of the intestinal microbiome to predict individual postprandial glucose excursions. In this post hoc study, we found microbial and clinical features, which predicted up to 48% of the inter-individual variance of postprandial plasma glucose responses (Pearson correlation coefficient of measured vs. predicted values, R = 0.69, 95% CI: 0.45 to 0.84, p<0.001). The features were age, fasting serum triglycerides, systolic blood pressure, BMI, fasting total serum cholesterol, abundance of Bifidobacterium genus, richness of metagenomics species and abundance of a metagenomic species annotated to Clostridiales at order level. A model based only on microbial features predicted up to 14% of the variance in postprandial plasma glucose excursions (R = 0.37, 95% CI: 0.02 to 0.64, p = 0.04). Adding fasting glycaemic measures to the model including microbial and bio-clinical features increased the predictive power to R = 0.78 (95% CI: 0.59 to 0.89, p<0.001), explaining more than 60% of the inter-individual variance of postprandial plasma glucose concentrations. The outcome of the study points to a potential role of the taxa and functional potentials of the intestinal microbiome. If validated in larger studies our findings may be included in future algorithms attempting to develop personalized nutrition, especially for prediction of individual blood glucose excursions in dys-glycaemic individuals.
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Affiliation(s)
- Nadja B. Søndertoft
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- * E-mail: (OP); (NBS)
| | - Josef K. Vogt
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Manimozhiyan Arumugam
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Mette Kristensen
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Rikke J. Gøbel
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Yong Fan
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Liwei Lyu
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Martin I. Bahl
- National Food Institute, Technical University of Denmark, Lyngby, Denmark
| | - Carsten Eriksen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Lars Ängquist
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Hanne Frøkiær
- Department of Veterinary Disease Biology, Faculty of Science, University of Copenhagen, Frederiksberg, Denmark
| | - Tue H. Hansen
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Susanne Brix
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | - Torben Hansen
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Vestergaard
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Ramneek Gupta
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Tine R. Licht
- National Food Institute, Technical University of Denmark, Lyngby, Denmark
| | - Lotte Lauritzen
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Oluf Pedersen
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- * E-mail: (OP); (NBS)
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28
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Nemet I, Saha PP, Gupta N, Zhu W, Romano KA, Skye SM, Cajka T, Mohan ML, Li L, Wu Y, Funabashi M, Ramer-Tait AE, Naga Prasad SV, Fiehn O, Rey FE, Tang WHW, Fischbach MA, DiDonato JA, Hazen SL. A Cardiovascular Disease-Linked Gut Microbial Metabolite Acts via Adrenergic Receptors. Cell 2020; 180:862-877.e22. [PMID: 32142679 DOI: 10.1016/j.cell.2020.02.016] [Citation(s) in RCA: 367] [Impact Index Per Article: 91.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 12/16/2019] [Accepted: 02/07/2020] [Indexed: 02/08/2023]
Abstract
Using untargeted metabolomics (n = 1,162 subjects), the plasma metabolite (m/z = 265.1188) phenylacetylglutamine (PAGln) was discovered and then shown in an independent cohort (n = 4,000 subjects) to be associated with cardiovascular disease (CVD) and incident major adverse cardiovascular events (myocardial infarction, stroke, or death). A gut microbiota-derived metabolite, PAGln, was shown to enhance platelet activation-related phenotypes and thrombosis potential in whole blood, isolated platelets, and animal models of arterial injury. Functional and genetic engineering studies with human commensals, coupled with microbial colonization of germ-free mice, showed the microbial porA gene facilitates dietary phenylalanine conversion into phenylacetic acid, with subsequent host generation of PAGln and phenylacetylglycine (PAGly) fostering platelet responsiveness and thrombosis potential. Both gain- and loss-of-function studies employing genetic and pharmacological tools reveal PAGln mediates cellular events through G-protein coupled receptors, including α2A, α2B, and β2-adrenergic receptors. PAGln thus represents a new CVD-promoting gut microbiota-dependent metabolite that signals via adrenergic receptors.
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Affiliation(s)
- Ina Nemet
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Prasenjit Prasad Saha
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Nilaksh Gupta
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Weifei Zhu
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Kymberleigh A Romano
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Sarah M Skye
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Tomas Cajka
- West Coast Metabolomics Center, University of California, Davis, Davis, CA 95616, USA
| | - Maradumane L Mohan
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Lin Li
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Yuping Wu
- Department of Mathematics, Cleveland State University, Cleveland, OH 44115, USA
| | - Masanori Funabashi
- Department of Bioengineering and ChEM-H, Stanford University, Stanford, CA 94305, USA
| | - Amanda E Ramer-Tait
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | | | - Oliver Fiehn
- West Coast Metabolomics Center, University of California, Davis, Davis, CA 95616, USA
| | - Federico E Rey
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - W H Wilson Tang
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA; Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Michael A Fischbach
- Department of Bioengineering and ChEM-H, Stanford University, Stanford, CA 94305, USA
| | - Joseph A DiDonato
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA
| | - Stanley L Hazen
- Department of Cardiovascular & Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA; Center for Microbiome & Human Health, Cleveland Clinic, Cleveland, OH 44106, USA; Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH 44106, USA.
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29
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Koppe L, Soulage CO. Preservation of residual kidney function to reduce non-urea solutes toxicity in haemodialysis. Nephrol Dial Transplant 2020; 35:733-736. [PMID: 31711183 DOI: 10.1093/ndt/gfz224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 10/04/2019] [Indexed: 12/24/2022] Open
Affiliation(s)
- Laetitia Koppe
- Department of Nephrology, Hospices Civils de Lyon, Centre Hospitalier Lyon-Sud, Pierre-Bénite, France.,Univ-Lyon, CarMeN lab, INSA Lyon, INSERM U1060, INRA, Université Claude Bernard Lyon 1, Villeurbanne, France
| | - Christophe O Soulage
- Univ-Lyon, CarMeN lab, INSA Lyon, INSERM U1060, INRA, Université Claude Bernard Lyon 1, Villeurbanne, France
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30
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Applying mass spectrometry-based assays to explore gut microbial metabolism and associations with disease. ACTA ACUST UNITED AC 2020; 58:719-732. [DOI: 10.1515/cclm-2019-0974] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 10/06/2019] [Indexed: 12/14/2022]
Abstract
AbstractThe workings of the gut microbiome have gained increasing interest in recent years through the mounting evidence that the microbiota plays an influential role in human health and disease. A principal focus of this research seeks to further understand the production of metabolic by-products produced by bacteria resident in the gut, and the subsequent interaction of these metabolites on host physiology and pathophysiology of disease. Gut bacterial metabolites of interest are predominately formed via metabolic breakdown of dietary compounds including choline and ʟ-carnitine (trimethylamine N-oxide), amino acids (phenol- and indole-containing uremic toxins) and non-digestible dietary fibers (short-chain fatty acids). Investigations have been accelerated through the application of mass spectrometry (MS)-based assays to quantitatively assess the concentration of these metabolites in laboratory- and animal-based experiments, as well as for direct circulating measurements in clinical research populations. This review seeks to explore the impact of these metabolites on disease, as well as to introduce the application of MS for those less accustomed to its use as a clinical tool, highlighting pertinent research related to its use for measurements of gut bacteria-mediated metabolites to further understand their associations with disease.
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31
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Rhee EP, Guallar E, Hwang S, Kim N, Tonelli M, Moe SM, Himmelfarb J, Thadhani RI, Powe NR, Shafi T. Prevalence and Persistence of Uremic Symptoms in Incident Dialysis Patients. ACTA ACUST UNITED AC 2020; 1:86-92. [PMID: 32529191 DOI: 10.34067/kid.0000072019] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Background Uremic symptoms are major contributors to the poor quality of life among patients on dialysis, but whether their prevalence or intensity has changed over time is unknown. Methods We examined responses to validated questionnaires in two incident dialysis cohort studies, the Choices for Health Outcomes in Caring for ESRD (CHOICE) study (N=926, 1995-1998) and the Longitudinal United States/Canada Incident Dialysis (LUCID) study (N=428, 2011-2017). We determined the prevalence and severity of uremic symptoms-anorexia, nausea/vomiting, pruritus, sleepiness, difficulty concentrating, fatigue, and pain-in both cohorts. Results In CHOICE and LUCID, respectively, mean age of the participants was 58 and 60 years, 53% and 60% were male, and 28% and 32% were black. In both cohorts, 54% of the participants had diabetes. Median time from dialysis initiation to the symptoms questionnaires was 45 days for CHOICE and 77 days for LUCID. Uremic symptom prevalence in CHOICE did not change from baseline to 1-year follow-up and was similar across CHOICE and LUCID. Baseline symptom prevalence in CHOICE and LUCID was as follows: anorexia (44%, 44%, respectively), nausea/vomiting (36%, 43%), pruritus (72%, 63%), sleepiness (86%, 68%), difficulty concentrating (55%, 57%), fatigue (89%, 77%), and pain (82%, 79%). In both cohorts, >80% of patients had three or more symptoms and >50% had five or more symptoms. The correlation between individual symptoms was low (ρ<0.5 for all comparisons). In CHOICE, no clinical or laboratory parameter was strongly associated with multiple symptoms. Conclusions The burden of uremic symptoms among patients on dialysis is substantial and has not changed in the past 15 years. Improving quality of life will require identification of the factors that underlie the pathogenesis of uremic symptoms and better ways of removing the toxins that are responsible.
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Affiliation(s)
- Eugene P Rhee
- Nephrology Division, Massachusetts General Hospital, Boston, Massachusetts.,Endocrinology Unit, Massachusetts General Hospital, Boston, Massachusetts
| | - Eliseo Guallar
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland
| | - Seungyoung Hwang
- Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland
| | - Noori Kim
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Marcello Tonelli
- Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sharon M Moe
- Division of Nephrology, Indiana University School of Medicine, Roudebush Veterans Administration Medical Center, Indianapolis, Indiana
| | - Jonathan Himmelfarb
- Kidney Research Institute, Division of Nephrology, University of Washington School of Medicine, Seattle, Washington
| | - Ravi I Thadhani
- Nephrology Division, Massachusetts General Hospital, Boston, Massachusetts
| | - Neil R Powe
- Department of Medicine, Zuckerberg San Francisco General Hospital, San Francisco, California
| | - Tariq Shafi
- Division of Nephrology, University of Mississippi Medical Center, Jackson, Mississippi
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32
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Indoxyl sulfate associates with cardiovascular phenotype in children with chronic kidney disease. Pediatr Nephrol 2019; 34:2571-2582. [PMID: 31428929 DOI: 10.1007/s00467-019-04331-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 05/09/2019] [Accepted: 08/06/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Cardiovascular disease is the leading cause of death in children with chronic kidney disease (CKD). Serum levels of gut-derived uremic toxins increase with deterioration of kidney function and are associated with cardiac comorbidities in adult CKD patients. METHODS Indoxyl sulfate (IS) and p-cresyl sulfate (pCS) were measured by high-performance liquid chromatography in serum of children participating in the Cardiovascular Comorbidity in Children with CKD (4C) Study. Results were correlated with measurements of the carotid intima-media thickness (cIMT), central pulse wave velocity (PWV), and left ventricular mass index (LVMI) in children aged 6-17 years with initial eGFR of 10-60 ml/min per 1.73 m2. RESULTS The median serum levels of total IS and of pCS, measured in 609 patients, were 5.3 μmol/l (8.7) and 17.0 μmol/l (21.6), respectively. In a multivariable regression model, IS and pCS showed significant positive associations with urea and negative associations with eGFR and uric acid. Furthermore, positive associations of pCS with age, serum albumin, and non-Mediterranean residency and a negative association with glomerular disease were observed. By multivariable regression analysis, only IS was significantly associated with a higher cIMT SDS at baseline and progression of PWV SDS within 12 months, independent of other risk factors. CONCLUSIONS Serum levels of gut-derived uremic toxins IS and pCS correlated inversely with eGFR in children. Only IS was significantly associated with surrogate markers of cardiovascular disease in this large pediatric CKD cohort.
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33
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van der Made TK, Fedecostante M, Scotcher D, Rostami-Hodjegan A, Sastre Toraño J, Middel I, Koster AS, Gerritsen KG, Jankowski V, Jankowski J, Hoenderop JGJ, Masereeuw R, Galetin A. Quantitative Translation of Microfluidic Transporter in Vitro Data to in Vivo Reveals Impaired Albumin-Facilitated Indoxyl Sulfate Secretion in Chronic Kidney Disease. Mol Pharm 2019; 16:4551-4562. [PMID: 31525064 DOI: 10.1021/acs.molpharmaceut.9b00681] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Indoxyl sulfate (IxS), a highly albumin-bound uremic solute, accumulates in chronic kidney disease (CKD) due to reduced renal clearance. This study was designed to specifically investigate the role of human serum albumin (HSA) in IxS renal secretion via organic anion transporter 1 (OAT1) in a microfluidic system and subsequently apply quantitative translation of in vitro data to predict extent of change in IxS renal clearance in CKD stage IV relative to healthy. Conditionally immortalized human proximal tubule epithelial cells overexpressing OAT1 were incubated with IxS (5-200 μM) in the HSA-free medium or in the presence of either HSA or CKD-modified HSA. IxS uptake in the presence of HSA resulted in more than 20-fold decrease in OAT1 affinity (Km,u) and 37-fold greater in vitro unbound intrinsic clearance (CLint,u) versus albumin-free condition. In the presence of CKD-modified albumin, Km,u increased four-fold and IxS CLint,u decreased almost seven-fold relative to HSA. Fold-change in parameters exceeded differences in IxS binding between albumin conditions, indicating additional mechanism and facilitating role of albumin in IxS OAT1-mediated uptake. Quantitative translation of IxS in vitro OAT1-mediated CLint,u predicted a 60% decrease in IxS renal elimination as a result of CKD, in agreement with the observed data (80%). The findings of the current study emphasize the role of albumin in IxS transport via OAT1 and explored the impact of modifications in albumin on renal excretion via active secretion in CKD. For the first time, this study performed quantitative translation of transporter kinetic data generated in a novel microfluidic in vitro system to a clinically relevant setting. Knowledge gaps and future directions in quantitative translation of renal drug disposition from microphysiological systems are discussed.
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Affiliation(s)
- Thomas K van der Made
- Centre for Applied Pharmacokinetic Research, School of Health Sciences , The University of Manchester , Manchester M13 9PL , U.K
| | | | - Daniel Scotcher
- Centre for Applied Pharmacokinetic Research, School of Health Sciences , The University of Manchester , Manchester M13 9PL , U.K
| | - Amin Rostami-Hodjegan
- Centre for Applied Pharmacokinetic Research, School of Health Sciences , The University of Manchester , Manchester M13 9PL , U.K.,Simcyp Division , Certara UK Limited , Sheffield S1 2BJ , U.K
| | | | | | | | - Karin G Gerritsen
- Department of Nephrology and Hypertension , University Medical Center Utrecht , Utrecht 3508 GA , The Netherlands
| | - Vera Jankowski
- Institute for Molecular Cardiovascular Research , RWTH Aachen University Hospital , Aachen 52074 , Germany
| | - Joachim Jankowski
- Institute for Molecular Cardiovascular Research , RWTH Aachen University Hospital , Aachen 52074 , Germany.,School for Cardiovascular Diseases , Maastricht University , Universiteitssingel 50 , Maastricht 6229 ER , The Netherlands
| | - Joost G J Hoenderop
- Department of Physiology, Radboud Institute for Molecular Life Sciences , Radboud University Medical Center , Nijmegen 6500 HB , The Netherlands
| | | | - Aleksandra Galetin
- Centre for Applied Pharmacokinetic Research, School of Health Sciences , The University of Manchester , Manchester M13 9PL , U.K
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34
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van Gennip ACE, Broers NJH, ter Meulen KJ, Canaud B, Christiaans MHL, Cornelis T, Gelens MACJ, Hermans MMH, Konings CJAM, van der Net JB, van der Sande FM, Schalkwijk CG, Stifft F, Wirtz JJJM, Kooman JP, Martens RJH. Endothelial dysfunction and low-grade inflammation in the transition to renal replacement therapy. PLoS One 2019; 14:e0222547. [PMID: 31518378 PMCID: PMC6743867 DOI: 10.1371/journal.pone.0222547] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/30/2019] [Indexed: 01/17/2023] Open
Abstract
Introduction End-stage renal disease (ESRD) strongly associates with cardiovascular disease (CVD) risk. This risk is not completely mitigated by renal replacement therapy. Endothelial dysfunction (ED) and low-grade inflammation (LGI) may contribute to the increased CVD risk. However, data on serum biomarkers of ED and LGI during the transition to renal replacement therapy (dialysis and kidney transplantation) are scarce. Methods We compared serum biomarkers of ED and LGI between 36 controls, 43 participants with chronic kidney disease (CKD) stage 5 non-dialysis (CKD5-ND), 20 participants with CKD stage 5 hemodialysis (CKD5-HD) and 14 participants with CKD stage 5 peritoneal dialysis (CKD5-PD). Further, in 34 and 15 participants repeated measurements were available during the first six months following dialysis initiation and kidney transplantation, respectively. Serum biomarkers of ED (sVCAM-1, E-selectin, P-selectin, thrombomodulin, sICAM-1, sICAM-3) and LGI (hs-CRP, SAA, IL-6, IL-8, TNF-α) were measured with a single- or multiplex array detection system based on electro-chemiluminescence technology. Results In linear regression analyses adjusted for potential confounders, participants with ESRD had higher levels of most serum biomarkers of ED and LGI than controls. In addition, in CKD5-HD levels of serum biomarkers of ED and LGI were largely similar to those in CKD5-ND. In contrast, in CKD5-PD levels of biomarkers of ED were higher than in CKD5-ND and CKD5-HD. Similarly, in linear mixed model analyses sVCAM-1, thrombomodulin, sICAM-1 and sICAM-3 increased after PD initiation. In contrast, incident HD patients showed an increase in sVCAM-1, P-selectin and TNF-α, but a decline of hs-CRP, SAA and IL-6. Further, following kidney transplantation sVCAM-1, thrombomodulin, sICAM-3 and TNF-α were lower at three months post-transplantation and remained stable in the three months thereafter. Conclusions Levels of serum biomarkers of ED and LGI were higher in ESRD as compared with controls. In addition, PD initiation and, less convincingly, HD initiation may increase levels of selected serum biomarkers of ED and LGI on top of uremia per se. In contrast to dialysis, several serum biomarkers of ED and LGI markedly declined following kidney transplantation.
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Affiliation(s)
- April C. E. van Gennip
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Natascha J. H. Broers
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
| | - Karlien J. ter Meulen
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Bernard Canaud
- Medical Office EMEA, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Germany
- Montpellier University, Montpellier, France
| | - Maarten H. L. Christiaans
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Tom Cornelis
- Department of Nephrology, Jessa Hospital, Hasselt, Belgium
| | - Mariëlle A. C. J. Gelens
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Marc M. H. Hermans
- Department of Internal Medicine, Division of Nephrology, Viecuri Medical Center, Venlo, the Netherlands
| | | | - Jeroen B. van der Net
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Frank M. van der Sande
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Casper G. Schalkwijk
- Department of Internal Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, the Netherlands
| | - Frank Stifft
- Department of Internal Medicine, Division of Nephrology, Zuyderland Medical Center, Sittard-Geleen, the Netherlands
| | - Joris J. J. M. Wirtz
- Department of Internal Medicine, Division of Nephrology, St. Laurentius Hospital, Roermond, the Netherlands
| | - Jeroen P. Kooman
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
- * E-mail:
| | - Remy J. H. Martens
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, Maastricht, the Netherlands
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, the Netherlands
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35
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Affiliation(s)
- H. M. Roager
- Department of Nutrition, Exercise and Sports University of Copenhagen Frederiksberg Denmark
| | - L. O. Dragsted
- Department of Nutrition, Exercise and Sports University of Copenhagen Frederiksberg Denmark
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36
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Martens RJH, Broers NJH, Canaud B, Christiaans MHL, Cornelis T, Gauly A, Hermans MMH, Konings CJAM, van der Sande FM, Scheijen JLJM, Stifft F, Wirtz JJJM, Kooman JP, Schalkwijk CG. Relations of advanced glycation endproducts and dicarbonyls with endothelial dysfunction and low-grade inflammation in individuals with end-stage renal disease in the transition to renal replacement therapy: A cross-sectional observational study. PLoS One 2019; 14:e0221058. [PMID: 31408493 PMCID: PMC6692010 DOI: 10.1371/journal.pone.0221058] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/29/2019] [Indexed: 02/07/2023] Open
Abstract
Background Cardiovascular disease (CVD) related mortality and morbidity are high in end-stage renal disease (ESRD). The pathophysiology of CVD in ESRD may involve non-traditional CVD risk factors, such as accumulation of advanced glycation endproducts (AGEs), dicarbonyls, endothelial dysfunction (ED) and low-grade inflammation (LGI). However, detailed data on the relation of AGEs and dicarbonyls with ED and LGI in ESRD are limited. Methods We examined cross-sectional Spearman’s rank correlations of AGEs and dicarbonyls with serum biomarkers of ED and LGI in 43 individuals with chronic kidney disease (CKD) stage 5 not on dialysis (CKD5-ND). Free and protein-bound serum AGEs (N∈-(carboxymethyl)lysine (CML), N∈-(carboxyethyl)lysine (CEL), Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)ornithine (MG-H1)) and serum dicarbonyls (glyoxal, methylglyoxal, 3-deoxyglucosone) were analyzed with tandem mass spectrometry, and tissue AGE accumulation was estimated by skin autofluorescence (SAF). Further, serum biomarkers of ED and LGI included sVCAM-1, sE-selectin, sP-selectin, sThrombomodulin, sICAM-1, sICAM-3, hs-CRP, SAA, IL-6, IL-8 and TNF-α. Results After adjustment for age, sex and diabetes status, protein-bound CML was positively correlated with sVCAM-1; free CEL with sVCAM-1 and sThrombomodulin; glyoxal with sThrombomodulin; and methylglyoxal with sVCAM-1 (correlation coefficients ranged from 0.36 to 0.44). In addition, free CML was positively correlated with SAA; protein-bound CML with IL-6; free CEL with hs-CRP, SAA and IL-6; free MG-H1 with SAA; protein-bound MG-H1 with IL-6; and MGO with hs-CRP and IL-6 (correlation coefficients ranged from 0.33 to 0.38). Additional adjustment for eGFR attenuated partial correlations of serum AGEs and serum dicarbonyls with biomarkers of ED and LGI. Conclusions In individuals with CKD5-ND, higher levels of serum AGEs and serum dicarbonyls were related to biomarkers of ED and LGI after adjustment for age, sex and diabetes mellitus. Correlations were attenuated by eGFR, suggesting that eGFR confounds and/or mediates the relation of serum AGEs and dicarbonyls with ED and LGI.
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Affiliation(s)
- Remy J. H. Martens
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, the Netherlands
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, the Netherlands
| | - Natascha J. H. Broers
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, the Netherlands
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
| | - Bernard Canaud
- Medical Office EMEA, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Germany
- Montpellier University, School of Medicine, Montpellier, France
| | - Maarten H. L. Christiaans
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, the Netherlands
| | - Tom Cornelis
- Department of Nephrology, Jessa Hospital, Hasselt, Belgium
| | - Adelheid Gauly
- Medical Office EMEA, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Germany
| | - Marc M. H. Hermans
- Department of Internal Medicine, Division of Nephrology, Viecuri Medical Center, Venlo, the Netherlands
| | - Constantijn J. A. M. Konings
- Department of Internal Medicine, Division of Nephrology, Catharina Hospital Eindhoven, Eindhoven, the Netherlands
| | - Frank M. van der Sande
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, the Netherlands
| | - Jean L. J. M. Scheijen
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, the Netherlands
- Department of Internal Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - Frank Stifft
- Department of Internal Medicine, Division of Nephrology, Zuyderland Medical Center, Sittard-Geleen, the Netherlands
| | - Joris J. J. M. Wirtz
- Department of Internal Medicine, Division of Nephrology, St. Laurentius Hospital, Roermond, the Netherlands
| | - Jeroen P. Kooman
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center+, the Netherlands
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, the Netherlands
- * E-mail: (JPK); (CGS)
| | - Casper G. Schalkwijk
- CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, the Netherlands
- Department of Internal Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
- * E-mail: (JPK); (CGS)
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37
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Bryniarski MA, Hamarneh F, Yacoub R. The role of chronic kidney disease-associated dysbiosis in cardiovascular disease. Exp Biol Med (Maywood) 2019; 244:514-525. [PMID: 30682892 PMCID: PMC6547008 DOI: 10.1177/1535370219826526] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
IMPACT STATEMENT Negative alterations, or dysbiosis, in the intestinal microbial community balance in response to chronic kidney disease is emerging as a substantial and important factor in inducing and exacerbating multiple comorbid conditions. Patients with renal insufficiency experience a substantial increase in cardiovascular risk, and recent evidence is shedding light on the close interaction between microbiome dysbiosis and increased cardiovascular events in this population. Previous association and recent causality studies utilizing experimental animal models have enriched our understanding and confirmed the impact of microbial community imbalance on cardiac health in both the general population and in patients with renal impairment.
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Affiliation(s)
- Mark A Bryniarski
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY 14214, USA
| | - Fares Hamarneh
- University College Dublin School of Medicine and Medical Science, Dublin, Ireland
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | - Rabi Yacoub
- Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
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38
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Hobby GP, Karaduta O, Dusio GF, Singh M, Zybailov BL, Arthur JM. Chronic kidney disease and the gut microbiome. Am J Physiol Renal Physiol 2019; 316:F1211-F1217. [PMID: 30864840 DOI: 10.1152/ajprenal.00298.2018] [Citation(s) in RCA: 131] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The gut microbiome is composed of a diverse population of bacteria that have beneficial and adverse effects on human health. The microbiome has recently gained attention and is increasingly noted to play a significant role in health and a number of disease states. Increasing urea concentration during chronic kidney disease (CKD) leads to alterations in the intestinal flora that can increase production of gut-derived toxins and alter the intestinal epithelial barrier. These changes can lead to an acceleration of the process of kidney injury. A number of strategies have been proposed to interrupt this pathway of injury in CKD. The purpose of this review is to summarize the role of the gut microbiome in CKD, tools used to study this microbial population, and attempts to alter its composition for therapeutic purposes.
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Affiliation(s)
- Gerren P Hobby
- Division of Nephrology, University of Arkansas for Medical Sciences , Little Rock, Arkansas
| | - Oleg Karaduta
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences , Little Rock, Arkansas
| | - Giuseppina F Dusio
- Division of Nephrology, University of Arkansas for Medical Sciences , Little Rock, Arkansas
| | - Manisha Singh
- Division of Nephrology, University of Arkansas for Medical Sciences , Little Rock, Arkansas.,Central Arkansas Veterans Health System, Little Rock, Arkansas
| | - Boris L Zybailov
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences , Little Rock, Arkansas
| | - John M Arthur
- Division of Nephrology, University of Arkansas for Medical Sciences , Little Rock, Arkansas.,Central Arkansas Veterans Health System, Little Rock, Arkansas
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Savira F, Magaye R, Hua Y, Liew D, Kaye D, Marwick T, Wang BH. Molecular mechanisms of protein-bound uremic toxin-mediated cardiac, renal and vascular effects: underpinning intracellular targets for cardiorenal syndrome therapy. Toxicol Lett 2019; 308:34-49. [PMID: 30872129 DOI: 10.1016/j.toxlet.2019.03.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 02/21/2019] [Accepted: 03/05/2019] [Indexed: 02/07/2023]
Abstract
Cardiorenal syndrome (CRS) remains a global health burden with a lack of definitive and effective treatment. Protein-bound uremic toxin (PBUT) overload has been identified as a non-traditional risk factor for cardiac, renal and vascular dysfunction due to significant albumin-binding properties, rendering these solutes non-dialyzable upon the state of irreversible kidney dysfunction. Although limited, experimental studies have investigated possible mechanisms in PBUT-mediated cardiac, renal and vascular effects. The ultimate aim is to identify relevant and efficacious targets that may translate beneficial outcomes in disease models and eventually in the clinic. This review will expand on detailed knowledge on mechanisms involved in detrimental effects of PBUT, specifically affecting the heart, kidney and vasculature, and explore potential effective intracellular targets to abolish their effects in CRS initiation and/or progression.
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Affiliation(s)
- Feby Savira
- Monash Centre of Cardiovascular Research and Education in Therapeutics, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - Ruth Magaye
- Monash Centre of Cardiovascular Research and Education in Therapeutics, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - Yue Hua
- Monash Centre of Cardiovascular Research and Education in Therapeutics, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - Danny Liew
- Monash Centre of Cardiovascular Research and Education in Therapeutics, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - David Kaye
- Baker Heart and Diabetes Research Institute, Melbourne, Victoria, Australia
| | - Tom Marwick
- Baker Heart and Diabetes Research Institute, Melbourne, Victoria, Australia
| | - Bing Hui Wang
- Monash Centre of Cardiovascular Research and Education in Therapeutics, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia; Baker Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
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40
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Snelson M, Kellow NJ, Coughlan MT. Modulation of the Gut Microbiota by Resistant Starch as a Treatment of Chronic Kidney Diseases: Evidence of Efficacy and Mechanistic Insights. Adv Nutr 2019; 10:303-320. [PMID: 30668615 PMCID: PMC6416045 DOI: 10.1093/advances/nmy068] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/17/2018] [Accepted: 08/12/2018] [Indexed: 12/14/2022] Open
Abstract
Chronic kidney disease (CKD) has been associated with changes in gut microbial ecology, or "dysbiosis," which may contribute to disease progression. Recent studies have focused on dietary approaches to favorably alter the composition of the gut microbial communities as a treatment method in CKD. Resistant starch (RS), a prebiotic that promotes proliferation of gut bacteria such as Bifidobacteria and Lactobacilli, increases the production of metabolites including short-chain fatty acids, which confer a number of health-promoting benefits. However, there is a lack of mechanistic insight into how these metabolites can positively influence renal health. Emerging evidence shows that microbiota-derived metabolites can regulate the incretin axis and mitigate inflammation via expansion of regulatory T cells. Studies from animal models and patients with CKD show that RS supplementation attenuates the concentrations of uremic retention solutes, including indoxyl sulfate and p-cresyl sulfate. Here, we present the current state of knowledge linking the microbiome to CKD, we explore the efficacy of RS in animal models of CKD and in humans with the condition, and we discuss how RS supplementation could be a promising dietary approach for slowing CKD progression.
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Affiliation(s)
- Matthew Snelson
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Nicole J Kellow
- Be Active Sleep & Eat (BASE) Facility, Department of Nutrition, Dietetics, and Food, Monash University, Notting Hill, Victoria, Australia
| | - Melinda T Coughlan
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Baker Heart Research Institute, Melbourne, Victoria, Australia
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Abstract
The measurement of select circulating metabolites such as creatinine, glucose, and cholesterol are integral to clinical medicine, with implications for diagnosis, prognosis, and treatment. Metabolomics studies in nephrology research seek to build on this paradigm, with the goal to identify novel markers and causal participants in the pathogenesis of kidney disease and its complications. This article reviews three themes pertinent to this goal. Each is rooted in long-established principles of human physiology, with recent updates enabled by metabolomics and other tools. First, the kidney has a broad and heterogeneous impact on circulating metabolites, with progressive loss of kidney function resulting in a multitude of small molecule alterations. Second, an increasing number of circulating metabolites have been shown to possess functional roles, in some cases acting as ligands for specific G-protein-coupled receptors. Third, circulating metabolites traffic through varied, and sometimes complex, interorgan circuits. Taken together, these themes emphasize the importance of viewing renal metabolomics at the systems level, recognizing the diverse origins and physiologic effects of blood metabolites. However, how to synthesize these themes and how to establish clinical relevance remain uncertain and will require further investigation.
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Affiliation(s)
- Eugene P Rhee
- Nephrology and Endocrinology Divisions, Massachusetts General Hospital, Boston, MA.
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42
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Watanabe I, Tatebe J, Fujii T, Noike R, Saito D, Koike H, Yabe T, Okubo R, Nakanishi R, Amano H, Toda M, Ikeda T, Morita T. Prognostic Significance of Serum Indoxyl Sulfate and Albumin for Patients with Cardiovascular Disease. Int Heart J 2018; 60:129-135. [PMID: 30464134 DOI: 10.1536/ihj.18-116] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The progression of renal dysfunction reduces serum albumin and deteriorates the binding capacity of protein-bound uremic toxins. We evaluated the prognostic implications of serum indoxyl sulfate (IS) and albumin levels in patients with cardiovascular disease.We prospectively enrolled 351 consecutive patients undergoing percutaneous revascularization for coronary artery disease or peripheral artery disease. The primary endpoint was all-cause mortality. Patients were assigned to four groups according to the median levels of serum IS (0.1 mg/dL) and albumin (3.9 g/dL).During the median follow-up time of 575 days, 16 patients died. The IS level was significantly higher in nonsurvivors (0.33 versus 0.85 mg/dL, P < 0.05). On the Kaplan-Meier curve, the high IS/low albumin group presented the highest mortality rate (log-rank test, P < 0.01). Cox proportional hazard analysis revealed that high IS/low albumin (hazard ratio (HR): 5.33; 95% confidence interval (CI): 1.71-16.5; P < 0.01), diastolic pressure (HR: 0.94; 95% CI: 0.91-0.98; P < 0.01), prior stroke (HR: 4.54; 95% CI: 1.33-15.4; P = 0.01), and left ventricular ejection fraction (LVEF) (HR: 0.92; 95% CI: 0.88-0.96; P < 0.001) were associated with increased mortality. Furthermore, the combination of IS and albumin levels significantly conferred an additive value to LVEF for predicting mortality (C-statistic: 0.69 versus 0.80; P < 0.001; net reclassification improvement: 0.83; P < 0.001; integrated discrimination improvement: 0.02; P = 0.02).A lower albumin level adds potentiating effects on IS as a prognostic factor for cardiovascular disease.
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Affiliation(s)
- Ippei Watanabe
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Junko Tatebe
- Department of Laboratory Medicine, Toho University Faculty of Medicine
| | - Takahiro Fujii
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Ryota Noike
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Daiga Saito
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Hideki Koike
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Takayuki Yabe
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Ryo Okubo
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Rine Nakanishi
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Hideo Amano
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Mikihito Toda
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Takanori Ikeda
- Division of Cardiovascular Medicine, Department of Internal Medicine, Toho University Faculty of Medicine
| | - Toshisuke Morita
- Department of Laboratory Medicine, Toho University Faculty of Medicine
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43
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Abstract
Patients with CKD exhibit a disproportionate burden of cardiovascular mortality, which likely stems from the presence of unique, nontraditional risk factors that accompany deteriorating kidney function. Mounting evidence suggests that alterations to the intestinal microbiome in CKD may serve as one such risk factor. The human intestinal tract is home to >100 trillion micro-organisms made up of a collection of commensal, symbiotic, and pathogenic species. These species along with their local environment constitute the intestinal microbiome. Patients with CKD show intestinal dysbiosis, an alteration of the gut micro-organism composition and function. Recent evidence links byproducts of intestinal dysbiosis to vascular calcification, atherosclerosis formation, and adverse cardiovascular outcomes in CKD. CKD-associated intestinal dysbiosis may also be accompanied by defects in intestinal barrier function, which could further enhance the negative effects of pathogenic intestinal bacteria in the human host. Thus, intestinal dysbiosis, defective intestinal barrier function, and a reduced capacity for clearance by the kidney of absorbed bacterial byproducts may all potentiate the development of cardiovascular disease in CKD. This narrative review focuses on microbiome-mediated mechanisms associated with CKD that may promote atherosclerosis formation and cardiovascular disease. It includes (1) new data supporting the hypothesis that intestinal barrier dysfunction leads to bacterial translocation and endotoxemia that potentiate systemic inflammation, (2) information on the accumulation of dietary-derived bacterial byproducts that stimulate pathways promoting atheromatous changes in arteries and cardiovascular disease, and (3) potential interventions. Despite great scientific interest in and a rapidly growing body of literature on the relationship between the microbiome and cardiovascular disease in CKD, many important questions remain unanswered.
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Affiliation(s)
- Anna Jovanovich
- Renal Section, Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado
- Division of Renal Diseases and Hypertension, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Tamara Isakova
- Division of Nephrology and Hypertension, Department of Medicine and Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois; and
| | - Jason Stubbs
- The Jared Grantham Kidney Institute, Department of Medicine, University of Kansas Medical Center, Kansas City, Kansas
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p-cresol sulfate and indoxyl sulfate: some clouds are gathering in the uremic toxin sky. Kidney Int 2018; 92:1323-1324. [PMID: 29153138 DOI: 10.1016/j.kint.2017.06.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 06/12/2017] [Indexed: 11/22/2022]
Abstract
An increasing body of experimental and clinical evidence suggests that p-cresol sulfate and indoxyl sulfate contribute to the high cardiovascular burden in patients with chronic kidney disease. In a post hoc analysis on the HEMO trial, Shafi et al. failed to confirm an association between total p-cresol sulfate and indoxyl sulfate and cardiovascular outcomes in dialysis patients. Analytical issues and case-mix may explain the discrepant findings.
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45
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Velasquez MT, Centron P, Barrows I, Dwivedi R, Raj DS. Gut Microbiota and Cardiovascular Uremic Toxicities. Toxins (Basel) 2018; 10:E287. [PMID: 29997362 PMCID: PMC6071268 DOI: 10.3390/toxins10070287] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/05/2018] [Accepted: 07/06/2018] [Indexed: 02/07/2023] Open
Abstract
Cardiovascular disease (CVD) remains a major cause of high morbidity and mortality in patients with chronic kidney disease (CKD). Numerous CVD risk factors in CKD patients have been described, but these do not fully explain the high pervasiveness of CVD or increased mortality rates in CKD patients. In CKD the loss of urinary excretory function results in the retention of various substances referred to as "uremic retention solutes". Many of these molecules have been found to exert toxicity on virtually all organ systems of the human body, leading to the clinical syndrome of uremia. In recent years, an increasing body of evidence has been accumulated that suggests that uremic toxins may contribute to an increased cardiovascular disease (CVD) burden associated with CKD. This review examined the evidence from several clinical and experimental studies showing an association between uremic toxins and CVD. Special emphasis is addressed on emerging data linking gut microbiota with the production of uremic toxins and the development of CKD and CVD. The biological toxicity of some uremic toxins on the myocardium and the vasculature and their possible contribution to cardiovascular injury in uremia are also discussed. Finally, various therapeutic interventions that have been applied to effectively reduce uremic toxins in patients with CKD, including dietary modifications, use of prebiotics and/or probiotics, an oral intestinal sorbent that adsorbs uremic toxins and precursors, and innovative dialysis therapies targeting the protein-bound uremic toxins are also highlighted. Future studies are needed to determine whether these novel therapies to reduce or remove uremic toxins will reduce CVD and related cardiovascular events in the long-term in patients with chronic renal failure.
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Affiliation(s)
- Manuel T Velasquez
- Division of Renal Diseases and Hypertension, The George Washington University, Washington, DC 20037, USA.
| | - Patricia Centron
- Division of Renal Diseases and Hypertension, The George Washington University, Washington, DC 20037, USA.
| | - Ian Barrows
- Department of Medicine, Georgetown University, Washington, DC 20007, USA.
| | - Rama Dwivedi
- Division of Renal Diseases and Hypertension, The George Washington University, Washington, DC 20037, USA.
- United States Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Dominic S Raj
- Division of Renal Diseases and Hypertension, The George Washington University, Washington, DC 20037, USA.
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46
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Uremic Toxins and Clinical Outcomes: The Impact of Kidney Transplantation. Toxins (Basel) 2018; 10:toxins10060229. [PMID: 29874852 PMCID: PMC6024850 DOI: 10.3390/toxins10060229] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 12/13/2022] Open
Abstract
Non-transplanted and transplanted patients with chronic kidney disease (CKD) differ in terms of mortality and the risk of clinical events. This difference is probably due to the difference of both traditional and non-traditional risk factors. Uremic retention solutes may constitute important non-traditional risk factors in this population. In the present review, we selected a set of uremic toxins that have been associated with harmful effects, and are an appealing target for adjuvant therapy in CKD. For each toxin reviewed here, relevant studies were selected and the relationship with hard clinical outcomes of uremic toxins were compared between non-transplanted CKD patients and transplanted patients taking into account the level of glomerular filtration rate in these two situations.
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47
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Serum metabolites are associated with all-cause mortality in chronic kidney disease. Kidney Int 2018; 94:381-389. [PMID: 29871777 DOI: 10.1016/j.kint.2018.03.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 01/31/2018] [Accepted: 03/02/2018] [Indexed: 11/23/2022]
Abstract
Chronic kidney disease (CKD) involves significant metabolic abnormalities and has a high mortality rate. Because the levels of serum metabolites in patients with CKD might provide insight into subclinical disease states and risk for future mortality, we determined which serum metabolites reproducibly associate with mortality in CKD using a discovery and replication design. Metabolite levels were quantified via untargeted liquid chromatography and mass spectroscopy from serum samples of 299 patients with CKD in the Modification of Diet in Renal Disease (MDRD) study as a discovery cohort. Six among 622 metabolites were significantly associated with mortality over a median follow-up of 17 years after adjustment for demographic and clinical covariates, including urine protein and measured glomerular filtration rate. We then replicated associations with mortality in 963 patients with CKD from the African American Study of Kidney Disease and Hypertension (AASK) cohort over a median follow-up of ten years. Three of the six metabolites identified in the MDRD cohort replicated in the AASK cohort: fumarate, allantoin, and ribonate, belonging to energy, nucleotide, and carbohydrate pathways, respectively. Point estimates were similar in both studies and in meta-analysis (adjusted hazard ratios 1.63, 1.59, and 1.61, respectively, per doubling of the metabolite). Thus, selected serum metabolites were reproducibly associated with long-term mortality in CKD beyond markers of kidney function in two well characterized cohorts, providing targets for investigation.
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48
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Huang M, Wei R, Wang Y, Su T, Li P, Chen X. The uremic toxin hippurate promotes endothelial dysfunction via the activation of Drp1-mediated mitochondrial fission. Redox Biol 2018; 16:303-313. [PMID: 29573704 PMCID: PMC5953222 DOI: 10.1016/j.redox.2018.03.010] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/14/2018] [Accepted: 03/15/2018] [Indexed: 12/31/2022] Open
Abstract
The accumulation of uremic toxins in chronic kidney disease (CKD) induces inflammation, oxidative stress and endothelial dysfunction, which is a key step in atherosclerosis. Accumulating evidence indicates increased mitochondrial fission is a contributing mechanism for impaired endothelial function. Hippurate, a uremic toxin, has been reported to be involved in cardiovascular diseases. Here, we assessed the endothelial toxicity of hippurate and the contribution of altered mitochondrial dynamics to hippurate-induced endothelial dysfunction. Treatment of human aortic endothelial cells with hippurate reduced the expression of endothelial nitric oxide synthase (eNOS) and increased the expression of intercellular cell adhesion molecule-1 (ICAM-1) and von Willebrand factor (vWF). The mechanisms of hippurate-induced endothelial dysfunction in vitro depended on the activation of Dynamin-related protein 1 (Drp1)-mediated mitochondrial fission and overproduction of mitochondrial reactive oxygen species (mitoROS). In a rat model in which CKD was induced by 5/6 nephrectomy (CKD rat), we observed increased oxidative stress, impaired endothelium-dependent vasodilation, and elevated soluble biomarkers of endothelial dysfunction (ICAM-1 and vWF). Similarly, endothelial dysfunction was identified in healthy rats treated with disease-relevant concentrations of hippurate. In aortas of CKD rats and hippurate-treated rats, we observed an increase in Drp1 protein levels and mitochondrial fission. Inhibition of Drp1 improved endothelial function in both rat models. These results indicate that hippurate, by itself, can cause endothelial dysfunction. Increased mitochondrial fission plays an active role in hippurate-induced endothelial dysfunction via an increase in mitoROS.
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Affiliation(s)
- Mengjie Huang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing 100853,People's Republic of China
| | - Ribao Wei
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing 100853,People's Republic of China.
| | - Yang Wang
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing 100853,People's Republic of China
| | - Tingyu Su
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing 100853,People's Republic of China
| | - Ping Li
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing 100853,People's Republic of China
| | - Xiangmei Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing 100853,People's Republic of China
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49
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Cosola C, Rocchetti MT, Cupisti A, Gesualdo L. Microbiota metabolites: Pivotal players of cardiovascular damage in chronic kidney disease. Pharmacol Res 2018. [PMID: 29518493 DOI: 10.1016/j.phrs.2018.03.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In chronic kidney disease (CKD), cardiovascular (CV) damage is present in parallel which leads to an increased risk of CV disease. Both traditional and non-traditional risk factors contribute to CV damage in CKD. The systemic role of the microbiota as a central player in the pathophysiology of many organs is progressively emerging in the literature: the microbiota is indeed involved in a complex, bi-directional network between many organs, including the kidney and heart connection, although many of these relationships still need to be elucidated through in-depth mechanistic studies. The aim of this review is to provide evidence that microbiota metabolites influence non-traditional risk factors, such as inflammation and endothelial dysfunction in CKD-associated CV damage. Here, we report our current understanding and hypotheses on the gut-kidney and gut-heart axes and provide details on the potential mechanisms mediated by microbial metabolites. More specifically, we summarize some novel hypotheses linking the microbiota to blood pressure regulation and hypertension. We also emphasise the idea that the nutritional management of CKD should be redesigned and include the new findings from research on the intrinsic plasticity of the microbiota and its metabolites in response to food intake. The need is felt to integrate the classical salt and protein restriction approach for CKD patients with foods that enhance intestinal wellness. Finally, we discuss the new perspectives, especially the importance of taking care of the microbiota in order to prevent the risk of developing CKD and hypertension, as well as the still not tested but very promising CKD innovative treatments, such as postbiotic supplementation and bacteriotherapy. This interesting area of research offers potential complementary approaches to the management of CKD and CV damage assuming that the causal mechanisms underlying the gut-kidney and gut-heart axes are clarified. This will pave the way to the design of new personalized therapies targeting gut microbiota.
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Affiliation(s)
- Carmela Cosola
- Department of Emergency and Organ Transplantation - Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari 70124, Italy.
| | - Maria Teresa Rocchetti
- Department of Emergency and Organ Transplantation - Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari 70124, Italy.
| | - Adamasco Cupisti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa 56126, Italy.
| | - Loreto Gesualdo
- Department of Emergency and Organ Transplantation - Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari 70124, Italy.
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50
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Rhee EP. How Omics Data Can Be Used in Nephrology. Am J Kidney Dis 2018; 72:129-135. [PMID: 29478865 DOI: 10.1053/j.ajkd.2017.12.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 12/10/2017] [Indexed: 02/07/2023]
Abstract
Advances in technology and computing now permit the high-throughput analysis of multiple domains of biological information, including the genome, transcriptome, proteome, and metabolome. These omics approaches, particularly comprehensive analysis of the genome, have catalyzed major discoveries in science and medicine, including in nephrology. However, they also generate large complex data sets that can be difficult to synthesize from a clinical perspective. This article seeks to provide an overview that makes omics technologies relevant to the practicing nephrologist, framing these tools as an extension of how we approach patient care in the clinic. More specifically, omics technologies reinforce the impact that genetic mutations can have on a range of kidney disorders, expand the catalogue of uremic molecules that accumulate in blood with kidney failure, enhance our ability to scrutinize urine beyond urinalysis for insight on renal pathology, and enable more extensive characterization of kidney tissue when a biopsy is performed. Although assay methodologies vary widely, all omics technologies share a common conceptual framework that embraces unbiased discovery at the molecular level. Ultimately, the application of these technologies seeks to elucidate a more mechanistic and individualized approach to the diagnosis and treatment of human disease.
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Affiliation(s)
- Eugene P Rhee
- Nephrology and Endocrinology Divisions, Massachusetts General Hospital, Boston, MA.
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