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R Muralitharan R, Nakai ME, Snelson M, Zheng T, Dinakis E, Xie L, Jama H, Paterson M, Shihata W, Wassef F, Vinh A, Drummond GR, Kaye DM, Mackay CR, Marques FZ. Influence of angiotensin II on the gut microbiome: Modest effects in comparison to experimental factors. Cardiovasc Res 2024:cvae062. [PMID: 38518247 DOI: 10.1093/cvr/cvae062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/12/2023] [Accepted: 01/08/2024] [Indexed: 03/24/2024] Open
Abstract
INTRODUCTION Animal models are regularly used to test the role of the gut microbiome in hypertension. Small-scale pre-clinical studies have investigated changes to the gut microbiome in the angiotensin II hypertensive model. However, the gut microbiome is influenced by internal and external experimental factors which are not regularly considered in the study design. Once these factors are accounted for, it is unclear if microbiome signatures are reproduceable. We aimed to determine the influence of angiotensin II treatment on the gut microbiome using a large and diverse cohort of mice and to quantify the magnitude by which other factors contribute to microbiome variations. METHODS AND RESULTS We conducted a retrospective study to establish a diverse mouse cohort resembling large human studies. We sequenced the V4 region of the 16S rRNA gene from 538 samples across the gastrointestinal tract of 303 male and female C57BL/6J mice randomised into sham or angiotensin II treatment from different genotypes, diets, animal facilities, and age groups. Analysing over 17 million sequencing reads, we observed that angiotensin II treatment influenced α-diversity (P = 0.0137) and β-diversity (i.e., composition of the microbiome, P < 0.001). Bacterial abundance analysis revealed patterns consistent with a reduction in short-chain fatty acid-producers, microbial metabolites that lower blood pressure. Furthermore, animal facility, genotype, diet, age, sex, intestinal sampling site, and sequencing batch had significant effects on both α- and β-diversity (all P < 0.001). Sampling site (6.8%) and diet (6%) had the largest impact on the microbiome, while angiotensin II and sex had the smallest effect (each 0.4%). CONCLUSIONS Our large-scale data confirmed findings from small-scale studies that angiotensin II impacted the gut microbiome. However, this effect was modest relative to most of the other factors studied. Accounting for these factors in future pre-clinical hypertensive studies will increase the likelihood that microbiome findings are replicable and translatable.
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Affiliation(s)
- Rikeish R Muralitharan
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
- Institute for Medical Research, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Michael E Nakai
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Matthew Snelson
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
- Victorian Heart Institute, Monash University, Melbourne, Australia
| | - Tenghao Zheng
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Evany Dinakis
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Liang Xie
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Hamdi Jama
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Madeleine Paterson
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Waled Shihata
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Flavia Wassef
- Department of Microbiology, Anatomy, Physiology, La Trobe University, Melbourne, Australia
| | - Antony Vinh
- Department of Microbiology, Anatomy, Physiology, La Trobe University, Melbourne, Australia
| | - Grant R Drummond
- Department of Microbiology, Anatomy, Physiology, La Trobe University, Melbourne, Australia
| | - David M Kaye
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia
- Department of Cardiology, Alfred Hospital, Melbourne, Australia
- Central Clinical School, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia
| | - Charles R Mackay
- Infection and Immunity Program, Monash Biodiscovery Institute, Monash University, Melbourne, Australia
- Department of Biochemistry, Monash University, Melbourne, Australia
- School of Pharmaceutical Sciences, Shandong Analysis and Test Center, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250014, China
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
- Victorian Heart Institute, Monash University, Melbourne, Australia
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia
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Gregor A, Panteva V, Bruckberger S, Auñon-Lopez A, Blahova S, Blahova V, Tevini J, Weber DD, Kofler B, Pignitter M, Duszka K. Energy and macronutrient restriction regulate bile acid homeostasis. J Nutr Biochem 2024; 124:109517. [PMID: 37925090 DOI: 10.1016/j.jnutbio.2023.109517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 10/20/2023] [Accepted: 10/31/2023] [Indexed: 11/06/2023]
Abstract
As we reported previously, caloric restriction (CR) results in an increased concentration of bile acids (BA) in the intestinal mucosa. We now investigated the background of this phenotype, trying to identify nutrition-related factors modulating BA levels. Male mice were submitted to various types of restrictive diets and BA levels and expression of associated factors were measured. We found that BA concentration is increased in the liver of CR mice, which corresponds to reduced expression of the Shp gene and elevated mRNA levels of Cyp27a1, Bal, and Ntcp, as well as CYP7A1 protein and gene expression. Correlation between decreased concentration of BAs in the feces, increased BAs levels in plasma, and elevated gene expression of BAs transporters in the ileum mucosa suggests enhanced BA uptake in the intestine of CR mice. Corresponding to CR upregulation of liver and ileum mucosa, BA concentration was found in animals submitted to other types of prolonged energy-restricting dietary protocols, including intermittent fasting and fasting-mimicking diet. While over-night fasting had negligible impact on BAs levels. Manipulation of macronutrient levels partly affected BA balance. Low-carbohydrate and ketogenic diet increased BAs in the liver but not in the intestine. Carbohydrate restriction stimulates BA synthesis in the liver, but energy restriction is required for the increase in BA levels in the intestine and its uptake.
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Affiliation(s)
- András Gregor
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Valeriya Panteva
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Stefan Bruckberger
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Arturo Auñon-Lopez
- Institute of Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria; Vienna Doctoral School in Chemistry (DoSChem), Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Sara Blahova
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Viktoria Blahova
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Julia Tevini
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, University Hospital of the Paracelsus Medical University, Salzburg, Austria
| | - Daniela D Weber
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, University Hospital of the Paracelsus Medical University, Salzburg, Austria
| | - Barbara Kofler
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, University Hospital of the Paracelsus Medical University, Salzburg, Austria
| | - Marc Pignitter
- Institute of Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Kalina Duszka
- Department of Nutritional Sciences, Faculty of Life Sciences, University of Vienna, Vienna, Austria.
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Hadžić K, Gregor A, Auernigg-Haselmaier S, Longo V, Pignitter M, Duszka K. Restrictive diets have a beneficial impact on dextran sodium sulfate-induced colitis in male mice. J Nutr 2024; 154:121-132. [PMID: 37952777 DOI: 10.1016/j.tjnut.2023.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/23/2023] [Accepted: 11/08/2023] [Indexed: 11/14/2023] Open
Abstract
BACKGROUND Previously, we assessed the impact of restrictive diets, including caloric restriction (CR), intermittent fasting (IF), or fasting-mimicking diet (FMD), on a healthy gastrointestinal tract. We revealed that each of the diets shows anti-inflammatory outcomes. OBJECTIVE The current study aimed to verify the diets' applicability in treating colitis. METHODS We exposed a mouse model with mild chronic dextran sodium sulfate (DSS)-induced colitis to ad libitum control feeding, CR, IF, or FMD. The collected samples were analyzed for markers of inflammation. RESULTS The diets reduced DSS-triggered increases in spleen weight and myeloperoxidase (MPO) activity. Diet intervention also influenced occludin levels, small intestine morphology, as well as cytokine and inflammatory gene expression, mainly in the mucosa of the proximal colon. The diets did not reverse DSS-enhanced gut permeability and thickening of the colon muscularis externa. Concerning inflammatory gene expression, the impact of DSS and the dietary intervention was limited to the colon as we did not measure major changes in the jejunum mucosa, Peyer's patches, and mesenteric lymph nodes. Further, rather modest changes in the concentration of intestinal bile acids were observed in response to the diets, whereas taurine and its conjugates levels were strongly affected. CONCLUSIONS Despite the differences in the dietary protocol, the tested diets showed very similar impacts and, therefore, may be interchangeable when aiming to reduce inflammation in the colon. However, FMD showed the most consistent beneficial impact.
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Affiliation(s)
- Kajs Hadžić
- Department of Nutritional Sciences, University of Vienna, Vienna, Austria
| | - András Gregor
- Department of Nutritional Sciences, University of Vienna, Vienna, Austria
| | | | - Valter Longo
- Longevity Institute, University of Southern California, Los Angeles, CA, United States
| | - Marc Pignitter
- Institute of Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Kalina Duszka
- Department of Nutritional Sciences, University of Vienna, Vienna, Austria.
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Gabarró-Solanas R, Davaatseren A, Kleifeld J, Kepčija T, Köcher T, Giralt A, Crespo-Enríquez I, Urbán N. Adult neural stem cells and neurogenesis are resilient to intermittent fasting. EMBO Rep 2023; 24:e57268. [PMID: 37987220 DOI: 10.15252/embr.202357268] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 09/13/2023] [Accepted: 10/30/2023] [Indexed: 11/22/2023] Open
Abstract
Intermittent fasting (IF) is a promising strategy to counteract ageing shown to increase the number of adult-born neurons in the dentate gyrus of mice. However, it is unclear which steps of the adult neurogenesis process are regulated by IF. The number of adult neural stem cells (NSCs) decreases with age in an activation-dependent manner and, to counteract this loss, adult NSCs are found in a quiescent state which ensures their long-term maintenance. We aimed to determine if and how IF affects adult NSCs in the hippocampus. To identify the effects of every-other-day IF on NSCs and all following steps in the neurogenic lineage, we combined fasting with lineage tracing and label retention assays. We show here that IF does not affect NSC activation or maintenance and, that contrary to previous reports, IF does not increase neurogenesis. The same results are obtained regardless of strain, sex, diet length, tamoxifen administration or new-born neuron identification method. Our data suggest that NSCs maintain homeostasis upon IF and that this intervention is not a reliable strategy to increase adult neurogenesis.
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Affiliation(s)
- Rut Gabarró-Solanas
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Amarbayasgalan Davaatseren
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Justus Kleifeld
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Tatjana Kepčija
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | | | - Albert Giralt
- Departament de Biomedicina, Facultat de Medicina, Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas (CIBERNED), Barcelona, Spain
- Production and Validation Center of Advanced Therapies (Creatio), Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Spain
| | - Iván Crespo-Enríquez
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
| | - Noelia Urbán
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Vienna, Austria
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Gozalo AS, Elkins WR. A Review of the Effects of Some Extrinsic Factors on Mice Used in Research. Comp Med 2023; 73:413-431. [PMID: 38217072 PMCID: PMC10752364 DOI: 10.30802/aalas-cm-23-000028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/20/2023] [Accepted: 11/15/2023] [Indexed: 01/14/2024]
Abstract
Animals have been used in research for over 2,000 y. From very crude experiments conducted by ancient scholars, animal research, as a science, was refined over hundreds of years to what we know it as today. However, the housing conditions of animals used for research did not improve significantly until less than 100 years ago when guidelines for housing research animals were first published. In addition, it was not until relatively recently that some extrinsic factors were recognized as a research variable, even when animals were housed under recommended guidelines. For example, temperature, humidity, light, noise, vibration, diet, water, caging, bedding, etc., can all potentially affect research using mice, contributing the inability of others to reproduce published findings. Consequently, these external factors should be carefully considered in the design, planning, and execution of animal experiments. In addition, as recommended by others, the housing and husbandry conditions of the animals should be described in detail in publications resulting from animal research to improve study reproducibility. Here, we briefly review some common, and less common, external factors that affect research in one of the most popular animal models, the mouse.
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Affiliation(s)
- Alfonso S Gozalo
- Comparative Medicine Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - William R Elkins
- Comparative Medicine Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
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Muralitharan RR, Snelson M, Meric G, Coughlan MT, Marques FZ. Guidelines for microbiome studies in renal physiology. Am J Physiol Renal Physiol 2023; 325:F345-F362. [PMID: 37440367 DOI: 10.1152/ajprenal.00072.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/28/2023] [Accepted: 07/07/2023] [Indexed: 07/15/2023] Open
Abstract
Gut microbiome research has increased dramatically in the last decade, including in renal health and disease. The field is moving from experiments showing mere association to causation using both forward and reverse microbiome approaches, leveraging tools such as germ-free animals, treatment with antibiotics, and fecal microbiota transplantations. However, we are still seeing a gap between discovery and translation that needs to be addressed, so that patients can benefit from microbiome-based therapies. In this guideline paper, we discuss the key considerations that affect the gut microbiome of animals and clinical studies assessing renal function, many of which are often overlooked, resulting in false-positive results. For animal studies, these include suppliers, acclimatization, baseline microbiota and its normalization, littermates and cohort/cage effects, diet, sex differences, age, circadian differences, antibiotics and sweeteners, and models used. Clinical studies have some unique considerations, which include sampling, gut transit time, dietary records, medication, and renal phenotypes. We provide best-practice guidance on sampling, storage, DNA extraction, and methods for microbial DNA sequencing (both 16S rRNA and shotgun metagenome). Finally, we discuss follow-up analyses, including tools available, metrics, and their interpretation, and the key challenges ahead in the microbiome field. By standardizing study designs, methods, and reporting, we will accelerate the findings from discovery to translation and result in new microbiome-based therapies that may improve renal health.
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Affiliation(s)
- Rikeish R Muralitharan
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Victoria, Australia
- Institute for Medical Research, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Matthew Snelson
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Guillaume Meric
- Cambridge-Baker Systems Genomics Initiative, Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Cardiometabolic Health, University of Melbourne, Melbourne, Victoria, Australia
- Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
- Department of Cardiovascular Research Translation and Implementation, La Trobe University, Melbourne, Victoria, Australia
| | - Melinda T Coughlan
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Victoria, Australia
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Victorian Heart Institute, Monash University, Melbourne, Victoria, Australia
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Sveeggen TM, Isakson BE, Straub AC, Bagher P. Bedding as a variable affecting fasting blood glucose and vascular physiology in mice. Am J Physiol Heart Circ Physiol 2023; 325:H338-H345. [PMID: 37389954 PMCID: PMC10435074 DOI: 10.1152/ajpheart.00168.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/05/2023] [Accepted: 06/20/2023] [Indexed: 07/02/2023]
Abstract
Rodent husbandry requires careful consideration of environmental factors that may impact colony performance and subsequent physiological studies. Of note, recent reports have suggested corncob bedding may affect a broad range of organ systems. As corncob bedding may contain digestible hemicelluloses, trace sugars, and fiber, we hypothesized that corncob bedding impacts overnight fasting blood glucose and murine vascular function. Here, we compared mice housed on corncob bedding, which were then fasted overnight on either corncob or ALPHA-dri bedding, a virgin paper pulp cellulose alternative. Male and female mice were used from two noninduced, endothelial-specific conditional knockout strains [Cadherin 5-cre/ERT2, floxed hemoglobin-α1 (Hba1fl/fl) or Cadherin 5-cre/ERT2, floxed cytochrome-B5 reductase 3 (CyB5R3fl/fl)] on a C57BL/6J genetic background. After fasting overnight, initial fasting blood glucose was measured, and mice were anesthetized with isoflurane for measurement of blood perfusion via laser speckle contrast analysis using a PeriMed PeriCam PSI NR system. After a 15-min equilibration, the mice were injected intraperitoneally with the α1-adrenergic receptor agonist, phenylephrine (5 mg/kg), or saline, and monitored for changes in blood perfusion. After a 15-min response period, blood glucose was remeasured postprocedure. In both strains, mice fasted on corncob bedding had higher blood glucose than the pulp cellulose group. In the CyB5R3fl/fl strain, mice housed on corncob bedding displayed a significant reduction in phenylephrine-mediated change in perfusion. In the Hba1fl/fl strain, phenylephrine-induced change in perfusion was not different in the corncob group. This work suggests that corncob bedding, in part due to its ingestion by mice, could impact vascular measurements and fasting blood glucose. To promote scientific rigor and improve reproducibility, bedding type should be routinely included in published methods.NEW & NOTEWORTHY This study demonstrates real-time measurement of changes in perfusion to pharmacological treatment using laser speckle contrast analysis. Furthermore, this investigation revealed that fasting mice overnight on corncob bedding has differential effects on vascular function and that there was increased fasting blood glucose in mice fasted on corncob bedding compared with paper pulp cellulose bedding. This highlights the impact that bedding type can have on outcomes in vascular and metabolic research and reinforces the need for thorough and robust reporting of animal husbandry practices.
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Affiliation(s)
- Timothy M Sveeggen
- Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
| | - Brant E Isakson
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia, United States
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, United States
| | - Adam C Straub
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Pooneh Bagher
- Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
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Klatt KC, Bass K, Speakman JR, Hall KD. Chowing down: diet considerations in rodent models of metabolic disease. LIFE METABOLISM 2023; 2:load013. [PMID: 37485302 PMCID: PMC10361708 DOI: 10.1093/lifemeta/load013] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Diet plays a substantial role in the etiology, progression, and treatment of chronic disease and is best considered as a multifaceted set of modifiable input variables with pleiotropic effects on a variety of biological pathways spanning multiple organ systems. This brief review discusses key issues related to the design and conduct of diet interventions in rodent models of metabolic disease and their implications for interpreting experiments. We also make specific recommendations to improve rodent diet studies to help better understand the role of diet on metabolic physiology and thereby improve our understanding of metabolic disease.
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Affiliation(s)
- Kevin C. Klatt
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Kevin Bass
- Garrison Institute of Aging, Texas Tech University Health Science Center, Lubbock, TX 79430, USA
| | - John R. Speakman
- Center for Energy Metabolism and Reproduction, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055, China
| | - Kevin D. Hall
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Roman LJ, Snijders AM, Chang H, Mao JH, Jones KJA, Lawson GW. Effect of Husbandry Practices on the Fecal Microbiota of C57BL/6J Breeding Colonies Housed in 2 Different Barrier Facilities in the Same Institution. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2023; 62:26-37. [PMID: 36755206 PMCID: PMC9936858 DOI: 10.30802/aalas-jaalas-22-000068] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Evidence showing a relationship between the mouse gut microbiome and properties such as phenotype and reaction to therapeutic agents and other treatments has increased significantly over the past 20 to 30 y. Recent concerns regarding the reproducibility of animal experiments have underscored the importance of understanding this relationship and how differences in husbandry practices can affect the gut microbiome. The current study focuses on effects of different barrier practices in 2 barrier facilities at the same institution on the fecal microbiome of breeding C57Bl/6J mice. Ten female and 10 male C57Bl/6J mice were obtained in one shipment from Jackson Laboratories and were housed under different barrier conditions upon arrival. Fecal samples were collected on arrival and periodically thereafter and were sent to TransnetYX for microbiome analysis. Mice used for collection of feces were housed as breeding pairs, with a total of 5 breeding pairs per barrier. An additional fecal sample was collected from these mice at 8 wk after arrival. One F1 female and one F1 male from each breeding cage were housed as brother-sister breeding pairs and a fecal sample was collected from them at 8 wk of age. Brother-sister breeding colonies were continued through F3, with fecal samples for microbiome analysis were collected from each generation at 8 wk of age. Breeding colonies in the 2 barriers showed differences in relative abundance, α -diversity, and β -diversity. Our data indicate that differences in barrier husbandry practices, including the use of autoclaved cages, the degree of restricted access, feed treatment practices, and water provision practices, can affect fecal microbiome divergence in both the parental and filial generations of different breeding colonies. To our knowledge, this is the first study to examine the effect of barrier husbandry practices on the microbiome of breeding colonies through the F3 generation.
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Affiliation(s)
- Libette J Roman
- Office of Laboratory Animal Care, University of California Berkeley, Berkeley, California,,Corresponding author.
| | - Antoine M Snijders
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Hang Chang
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Jian-Hua Mao
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California
| | - Kristina JA Jones
- Office of Laboratory Animal Care, University of California Berkeley, Berkeley, California
| | - Gregory W Lawson
- Office of Laboratory Animal Care, University of California Berkeley, Berkeley, California
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Dasinger JH, Walton SD, Burns EC, Cherian-Shaw M, Abais-Battad JM, Mattson DL. Impact of bedding on Dahl salt-sensitive hypertension and renal damage. Am J Physiol Renal Physiol 2022; 323:F666-F672. [PMID: 36108053 PMCID: PMC9705021 DOI: 10.1152/ajprenal.00201.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/13/2022] [Accepted: 09/13/2022] [Indexed: 12/14/2022] Open
Abstract
Salt-sensitive hypertension, increases in blood pressure in response to increased salt intake, is associated with an increased risk of morbidity, mortality, and end-organ damage compared with salt-resistant hypertension. The Dahl salt-sensitive (SS) rat mimics the phenotypic characteristics observed in human hypertension when rats are challenged with a high-salt diet. Our previous work demonstrated that environmental factors, such as dietary protein, alter the severity of salt sensitivity in Dahl SS rats and should be an important consideration in experimental design. The present study investigated how the bedding on which animals were maintained (wood vs. corncob) could impact the SS phenotype in the Dahl SS rat. Animals that were maintained on corncob bedding exhibited a significant attenuation in blood pressure and renal end-organ damage in response to a high-salt diet compared with animals maintained on wood bedding. This attenuation was associated with an improvement in renal function and reduction in immune cell infiltration into the kidneys of Dahl SS rats maintained on corncob bedding. These results indicate that the type of bedding impacts the SS phenotype in the Dahl SS rat and that the bedding used in experiments can be a confounding factor to consider during data interpretation and experimental design.NEW & NOTEWORTHY Results from our present study demonstrate the profound effect of animal bedding on the severity of salt-sensitive hypertension, renal damage, and inflammation in Dahl salt-sensitive rats. This study highlights the important consideration that should be given to environmental factors, namely, the type of bedding in animal facilities, in experimental design and data interpretation.
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Affiliation(s)
- John Henry Dasinger
- Department of Physiology, Medical College of Georgia, grid.410427.4Augusta University, Augusta, Georgia
| | - Samuel D Walton
- Department of Physiology, Medical College of Georgia, grid.410427.4Augusta University, Augusta, Georgia
| | - Emily C Burns
- Department of Physiology, Medical College of Georgia, grid.410427.4Augusta University, Augusta, Georgia
| | - Mary Cherian-Shaw
- Department of Physiology, Medical College of Georgia, grid.410427.4Augusta University, Augusta, Georgia
| | - Justine M Abais-Battad
- Department of Physiology, Medical College of Georgia, grid.410427.4Augusta University, Augusta, Georgia
| | - David L Mattson
- Department of Physiology, Medical College of Georgia, grid.410427.4Augusta University, Augusta, Georgia
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Bartochowski P, Gayrard N, Bornes S, Druart C, Argilés A, Cordaillat-Simmons M, Duranton F. Gut–Kidney Axis Investigations in Animal Models of Chronic Kidney Disease. Toxins (Basel) 2022; 14:toxins14090626. [PMID: 36136564 PMCID: PMC9502418 DOI: 10.3390/toxins14090626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/01/2022] [Accepted: 09/01/2022] [Indexed: 11/16/2022] Open
Abstract
Chronic kidney disease (CKD) is an incurable disease in which renal function gradually declines, resulting in no noticeable symptoms during the early stages and a life-threatening disorder in the latest stage. The changes that accompany renal failure are likely to influence the gut microbiota, or the ecosystem of micro-organisms resident in the intestine. Altered gut microbiota can display metabolic changes and become harmful to the host. To study the gut–kidney axis in vivo, animal models should ideally reproduce the disorders affecting both the host and the gut microbiota. Murine models of CKD, but not dog, manifest slowed gut transit, similarly to patient. Animal models of CKD also reproduce altered intestinal barrier function, as well as the resulting leaky gut syndrome and bacterial translocation. CKD animal models replicate metabolic but not compositional changes in the gut microbiota. Researchers investigating the gut–kidney axis should pay attention to the selection of the animal model (disease induction method, species) and the setting of the experimental design (control group, sterilization method, individually ventilated cages) that have been shown to influence gut microbiota.
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Affiliation(s)
- Piotr Bartochowski
- RD Néphrologie SAS, 34090 Montpellier, France
- BC2M, Faculty of Pharmacy, University of Montpellier, 34090 Montpellier, France
| | - Nathalie Gayrard
- RD Néphrologie SAS, 34090 Montpellier, France
- BC2M, Faculty of Pharmacy, University of Montpellier, 34090 Montpellier, France
- Correspondence:
| | - Stéphanie Bornes
- Université Clermont Auvergne, Inrae, Vetagro Sup, UMRF0545, 15000 Aurillac, France
| | - Céline Druart
- Pharmabiotic Research Institute (PRI), 11100 Narbonne, France
| | - Angel Argilés
- RD Néphrologie SAS, 34090 Montpellier, France
- BC2M, Faculty of Pharmacy, University of Montpellier, 34090 Montpellier, France
| | | | - Flore Duranton
- RD Néphrologie SAS, 34090 Montpellier, France
- BC2M, Faculty of Pharmacy, University of Montpellier, 34090 Montpellier, France
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Gregor A, Huber L, Auernigg-Haselmaier S, Sternberg F, Billerhart M, Dunkel A, Somoza V, Ogris M, Kofler B, Longo VD, König J, Duszka K. A Comparison of the Impact of Restrictive Diets on the Gastrointestinal Tract of Mice. Nutrients 2022; 14:nu14153120. [PMID: 35956298 PMCID: PMC9370610 DOI: 10.3390/nu14153120] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 11/16/2022] Open
Abstract
The rate of gut inflammatory diseases is growing in modern society. Previously, we showed that caloric restriction (CR) shapes gut microbiota composition and diminishes the expression of inflammatory factors along the gastrointestinal (GI) tract. The current project aimed to assess whether prominent dietary restrictive approaches, including intermittent fasting (IF), fasting-mimicking diet (FMD), and ketogenic diet (KD) have a similar effect as CR. We sought to verify which of the restrictive dietary approaches is the most potent and if the molecular pathways responsible for the impact of the diets overlap. We characterized the impact of the diets in the context of several dietary restriction-related parameters, including immune status in the GI tract; microbiota and its metabolites; bile acids (BAs); gut morphology; as well as autophagy-, mitochondria-, and energy restriction-related parameters. The effects of the various diets are very similar, particularly between CR, IF, and FMD. The occurrence of a 50 kDa truncated form of occludin, the composition of the microbiota, and BAs distinguished KD from the other diets. Based on the results, we were able to provide a comprehensive picture of the impact of restrictive diets on the gut, indicating that restrictive protocols aimed at improving gut health may be interchangeable.
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Affiliation(s)
- András Gregor
- Department of Nutritional Sciences, University of Vienna, 1090 Vienna, Austria; (A.G.); (L.H.); (S.A.-H.); (J.K.)
| | - Laura Huber
- Department of Nutritional Sciences, University of Vienna, 1090 Vienna, Austria; (A.G.); (L.H.); (S.A.-H.); (J.K.)
| | - Sandra Auernigg-Haselmaier
- Department of Nutritional Sciences, University of Vienna, 1090 Vienna, Austria; (A.G.); (L.H.); (S.A.-H.); (J.K.)
| | - Felix Sternberg
- Department of Biomedical Sciences, Institute of Physiology, Pathophysiology and Biophysics, University of Veterinary Medicine, 1210 Vienna, Austria;
| | - Magdalena Billerhart
- Laboratory of Macromolecular Cancer Therapeutics (MMCT), Department of Pharmaceutical Sciences, University of Vienna, 1090 Vienna, Austria; (M.B.); (M.O.)
| | - Andreas Dunkel
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, 85354 Freising, Germany; (A.D.); (V.S.)
| | - Veronika Somoza
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, 85354 Freising, Germany; (A.D.); (V.S.)
| | - Manfred Ogris
- Laboratory of Macromolecular Cancer Therapeutics (MMCT), Department of Pharmaceutical Sciences, University of Vienna, 1090 Vienna, Austria; (M.B.); (M.O.)
| | - Barbara Kofler
- Research Program for Receptor Biochemistry and Tumor Metabolism, Department of Pediatrics, University Hospital of the Paracelsus Medical University, 5020 Salzburg, Austria;
| | - Valter D. Longo
- Longevity Institute, Leonard Davis, Los Angeles, CA 90089, USA;
| | - Jürgen König
- Department of Nutritional Sciences, University of Vienna, 1090 Vienna, Austria; (A.G.); (L.H.); (S.A.-H.); (J.K.)
| | - Kalina Duszka
- Department of Nutritional Sciences, University of Vienna, 1090 Vienna, Austria; (A.G.); (L.H.); (S.A.-H.); (J.K.)
- Correspondence:
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Versatile Triad Alliance: Bile Acid, Taurine and Microbiota. Cells 2022; 11:cells11152337. [PMID: 35954180 PMCID: PMC9367564 DOI: 10.3390/cells11152337] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/21/2022] [Accepted: 07/24/2022] [Indexed: 11/21/2022] Open
Abstract
Taurine is the most abundant free amino acid in the body, and is mainly derived from the diet, but can also be produced endogenously from cysteine. It plays multiple essential roles in the body, including development, energy production, osmoregulation, prevention of oxidative stress, and inflammation. Taurine is also crucial as a molecule used to conjugate bile acids (BAs). In the gastrointestinal tract, BAs deconjugation by enteric bacteria results in high levels of unconjugated BAs and free taurine. Depending on conjugation status and other bacterial modifications, BAs constitute a pool of related but highly diverse molecules, each with different properties concerning solubility and toxicity, capacity to activate or inhibit receptors of BAs, and direct and indirect impact on microbiota and the host, whereas free taurine has a largely protective impact on the host, serves as a source of energy for microbiota, regulates bacterial colonization and defends from pathogens. Several remarkable examples of the interaction between taurine and gut microbiota have recently been described. This review will introduce the necessary background information and lay out the latest discoveries in the interaction of the co-reliant triad of BAs, taurine, and microbiota.
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Pickel L, Lee JH, Maughan H, Shi IQ, Verma N, Yeung C, Guttman D, Sung H. Circadian rhythms in metabolic organs and the microbiota during acute fasting in mice. Physiol Rep 2022; 10:e15393. [PMID: 35851583 PMCID: PMC9295129 DOI: 10.14814/phy2.15393] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/15/2022] [Accepted: 06/21/2022] [Indexed: 04/16/2023] Open
Abstract
The circadian clock regulates metabolism in anticipation of regular changes in the environment. It is found throughout the body, including in key metabolic organs such as the liver, adipose tissues, and intestine, where the timing of the clock is set largely by nutrient signaling. However, the circadian clocks of these tissues during the fasted state have not been completely characterized. Moreover, the sufficiency of a functioning host clock to produce diurnal rhythms in the composition of the microbiome in fasted animals has not been explored. To this end, mice were fasted 24 h prior to collection of key metabolic tissues and fecal samples for the analysis of circadian clock gene expression and microbiome composition. Rhythm characteristics were determined using CircaCompare software. We identify tissue-specific changes to circadian clock rhythms upon fasting, particularly in the brown adipose tissue, and for the first time demonstrate the rhythmicity of the microbiome in fasted animals.
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Affiliation(s)
- Lauren Pickel
- Translational Medicine Program, The Hospital for Sick ChildrenTorontoOntarioUSA
| | - Ju Hee Lee
- Translational Medicine Program, The Hospital for Sick ChildrenTorontoOntarioUSA
- Department of Laboratory Medicine and PathologyUniversity of TorontoTorontoOntarioUSA
| | | | - Irisa Qianwen Shi
- Translational Medicine Program, The Hospital for Sick ChildrenTorontoOntarioUSA
| | - Navkiran Verma
- Translational Medicine Program, The Hospital for Sick ChildrenTorontoOntarioUSA
- Department of Laboratory Medicine and PathologyUniversity of TorontoTorontoOntarioUSA
| | - Christy Yeung
- Translational Medicine Program, The Hospital for Sick ChildrenTorontoOntarioUSA
- Department of Laboratory Medicine and PathologyUniversity of TorontoTorontoOntarioUSA
| | - David Guttman
- Centre for the Analysis of Genome Evolution & FunctionUniversity of TorontoTorontoOntarioUSA
| | - Hoon‐Ki Sung
- Translational Medicine Program, The Hospital for Sick ChildrenTorontoOntarioUSA
- Department of Laboratory Medicine and PathologyUniversity of TorontoTorontoOntarioUSA
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Colonic Medium-Chain Fatty Acids Act as a Source of Energy and for Colon Maintenance but Are Not Utilized to Acylate Ghrelin. Nutrients 2021; 13:nu13113807. [PMID: 34836064 PMCID: PMC8617845 DOI: 10.3390/nu13113807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/19/2021] [Accepted: 10/23/2021] [Indexed: 01/04/2023] Open
Abstract
The capacity of microbiota to produce medium-chain fatty acids (MCFA) and related consequences for the gastrointestinal (GI) tract have never been reported before. We verified the impact of nutrition-related factors on fatty acid (FAs) production and found that caloric restriction decreased levels of most of MCFAs in the mouse cecum, whereas overnight fasting reduced the levels of acetate and butyrate but increased propionate and laurate. A diet high in soluble fibre boosted the production of short-chain fatty acids (SCFA) and caproate whereas a high-cellulose diet did not have an effect or decreased the levels of some of the FAs. Rectal infusion of caprylate resulted in its rapid metabolism for energy production. Repeated 10-day MCFA infusion impacted epididymal white adipose tissue (eWAT) weight and lipid accumulation. Repeated infusion of caprylate rectally tended to increase the concentration of active ghrelin in mice plasma; however, this increase was not statistically significant. In Caco-2 cells, caprylate increased the expression of Fabp2, Pdk4, Tlr3, and Gpr40 genes as well as counteracted TNFα-triggered downregulation of Pparγ, Occludin, and Zonulin mRNA expression. In conclusion, we show that colonic MCFAs can be rapidly utilized as a source of energy or stored as a lipid supply. Further, locally produced caprylate may impact metabolism and inflammatory parameters in the colon.
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