1
|
Nesvadba D, Sime N, Jansen J. Measurement of the calorific content of propofol using bomb calorimetry. J Intensive Care Soc 2023; 24:27-28. [PMID: 37928073 PMCID: PMC10621515 DOI: 10.1177/1751143720940686] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2023] Open
Affiliation(s)
- David Nesvadba
- Department of Anaesthesia, Aberdeen Royal Infirmary, Aberdeen, UK
| | - Nicole Sime
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen UK
| | - Jan Jansen
- Department of Surgery, School of Medicine, University of Alabama at Birmingham, Birmingham, USA
| |
Collapse
|
2
|
Morgavi DP, Cantalapiedra-Hijar G, Eugène M, Martin C, Noziere P, Popova M, Ortigues-Marty I, Muñoz-Tamayo R, Ungerfeld EM. Review: Reducing enteric methane emissions improves energy metabolism in livestock: is the tenet right? Animal 2023; 17 Suppl 3:100830. [PMID: 37263815 DOI: 10.1016/j.animal.2023.100830] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/21/2022] [Accepted: 12/30/2022] [Indexed: 06/03/2023] Open
Abstract
The production of enteric methane in the gastrointestinal tract of livestock is considered as an energy loss in the equations for estimating energy metabolism in feeding systems. Therefore, the spared energy resulting from specific inhibition of methane emissions should be re-equilibrated with other factors of the equation. And, it is commonly assumed that net energy from feeds increases, thus benefitting production functions, particularly in ruminants due to the important production of methane in the rumen. Notwithstanding, we confirm in this work that inhibition of emissions in ruminants does not transpose into consistent improvements in production. Theoretical calculations of energy flows using experimental data show that the expected improvement in net energy for production is small and difficult to detect under the prevailing, moderate inhibition of methane production (≈25%) obtained using feed additives inhibiting methanogenesis. Importantly, the calculation of energy partitioning using canonical models might not be adequate when methanogenesis is inhibited. There is a lack of information on various parameters that play a role in energy partitioning and that may be affected under provoked abatement of methane. The formula used to calculate heat production based on respiratory exchanges should be validated when methanogenesis is inhibited. Also, a better understanding is needed of the effects of inhibition on fermentation products, fermentation heat, and microbial biomass. Inhibition induces the accumulation of H2, the main substrate used to produce methane, that has no energetic value for the host, and it is not extensively used by the majority of rumen microbes. Currently, the fate of this excess of H2 and its consequences on the microbiota and the host are not well known. All this additional information will provide a better account of energy transactions in ruminants when enteric methanogenesis is inhibited. Based on the available information, it is concluded that the claim that enteric methane inhibition will translate into more feed-efficient animals is not warranted.
Collapse
Affiliation(s)
- D P Morgavi
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France.
| | - G Cantalapiedra-Hijar
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France
| | - M Eugène
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France
| | - C Martin
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France
| | - P Noziere
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France
| | - M Popova
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France
| | - I Ortigues-Marty
- Université Clermont Auvergne, INRAE, VetAgro Sup, UMR Herbivores, F-63122 Saint-Genes-Champanelle, France
| | - R Muñoz-Tamayo
- Université Paris-Saclay, INRAE, AgroParisTech, UMR Modélisation Systémique Appliquée aux Ruminants, 91120 Palaiseau, France
| | - E M Ungerfeld
- Centro Regional de Investigación Carillanca, Instituto de Investigaciones Agropecuarias INIA, Temuco 4880000, Chile
| |
Collapse
|
3
|
Fradkin M, Elyashiv M, Brik M, Kait MG, Albukrek D, Singer P, Dankner R. The efficacy of calorimetry-based nutritional support versus recommended dietary intake-based nutritional support in the successful weaning of chronically ventilated patients: A study protocol for a double blind randomized controlled trial. Clin Nutr ESPEN 2023; 54:94-97. [PMID: 36963903 DOI: 10.1016/j.clnesp.2023.01.003] [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: 04/19/2022] [Revised: 12/13/2022] [Accepted: 01/03/2023] [Indexed: 01/15/2023]
Abstract
BACKGROUND & AIMS Mechanically ventilated patients are weaned during acute care hospitalization when it is determined that they are ready for withdrawal. If weaning fails, patients are admitted to a rehabilitation medical center for continued supportive care and additional weaning attempts. This study's objective is to increase the success rate of weaning from prolonged mechanical ventilation (PMV), and to shorten the overall weaning period by tailoring the patient's caloric intake according to their individually measured energy needs. METHODS We designed a randomized, controlled, double-blinded trial to be conducted among PMV patients undergoing routine ventilation-weaning attempts. Patients in the intervention arm will be fed according to energy needs determined by calorimetry. Patients in the control arm will be fed according to the standard of care, namely the Recommended Dietary Allowance (RDA) guidelines. Each patient will undergo up to five weaning attempts. Study outcomes will include successful weaning rate, time to successful weaning, and 3-12 months survival rate. DISCUSSION This trial aims to examine the safety and efficacy of a nutritional diet based on an individual's measured caloric needs in terms of weaning rates and weaning time. We hypothesize that calorimetry-based nutrition plan will prove to be superior in both success rate and time to successful weaning compared to the standard nutrition plan based on the resting energy expenditure (REE) formula during the weaning process. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT04825717.
Collapse
Affiliation(s)
- Mila Fradkin
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Schoenbrun Academic Nursing School, Sourasky Medical Center, Tel Aviv, Israel.
| | - Maya Elyashiv
- Intubation Unit, Reuth Rehabilitation Medical Center, Tel Aviv, Israel.
| | - Michael Brik
- Reuth Research and Development Institute, Reuth Rehabilitation Medical Center, Tel Aviv, Israel.
| | - Michal G Kait
- Reuth Nutritional Department, Reuth Rehabilitation Medical Center, Tel Aviv, Israel.
| | - Dov Albukrek
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Reuth Rehabilitation Medical Center, Tel Aviv, Israel.
| | - Pierre Singer
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; General Intensive Care Department and Institute for Nutrition Research, Rabin Medical Center, Beilinson Hospital, Israel.
| | - Rachel Dankner
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Reuth Research and Development Institute, Reuth Rehabilitation Medical Center, Tel Aviv, Israel.
| |
Collapse
|
4
|
Bryla A, Zagkle E, Sadowska ET, Cichoń M, Bauchinger U. Measurements of body temperature and oxidative stress reveal differential costs associated with humoral immune function in a passerine bird. J Exp Biol 2022; 225:279339. [PMID: 36314237 DOI: 10.1242/jeb.244897] [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: 08/31/2022] [Accepted: 10/19/2022] [Indexed: 11/05/2022]
Abstract
Eco-immunology considers resistance to antigens a costly trait for an organism, but actual quantification of such costs is not straightforward. Costs of the immune response are visible in impaired coloration and reduced growth or reproductive success. Activation of the humoral immune response is a slow, complex and long-lasting process, which makes the quantification of its energetic cost a potential losing game. We implemented near-continuous measurements of body temperature in zebra finches (Taeniopygia guttata) as a proxy for the energetic cost, with a particular focus during activation of the humoral immune response until the peak of antibody release several days later. At the peak of the antibody release we additionally measured oxygen consumption (open-flow respirometry) and markers of oxidative stress (dROMs, OXY). Birds with an activated immune response maintained a higher night-time body temperature during the first 4 nights after an immune challenge in comparison to controls, implying increased night-time energy use. At peak antibody production, we did not find differences in night-time body temperature and oxygen consumption but observed differentiated results for oxygen consumption during the day. Immune-challenged females had significantly higher oxygen consumption compared with other groups. Moreover, we found that activation of the humoral immune response increases oxidative damage, a potential cost of maintaining the higher night-time body temperature that is crucial at the early stage of the immune response. The costs generated by the immune system appear to consist of two components - energetic and non-energetic - and these appear to be separated in time.
Collapse
Affiliation(s)
- Amadeusz Bryla
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Elisavet Zagkle
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Edyta T Sadowska
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Mariusz Cichoń
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland
| | - Ulf Bauchinger
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, 30-387 Krakow, Poland.,Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland
| |
Collapse
|
5
|
Evans BL, Hurlstone AF, Clayton PE, Stevens A, Shiels HA. Glucose uptake as an alternative to oxygen uptake for assessing metabolic rate in Danio rerio Larvae. Curr Res Physiol 2022; 5:216-223. [PMID: 35637870 PMCID: PMC9142652 DOI: 10.1016/j.crphys.2022.05.002] [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: 02/04/2022] [Revised: 05/03/2022] [Accepted: 05/11/2022] [Indexed: 11/25/2022] Open
Abstract
Respirometry, based on oxygen uptake, is commonly employed for measuring metabolic rate. There is a growing need for metabolic rate measurements suitable for developmental studies, particularly in Danio rerio, where many important developmental stages occur at < 4 mm. However, respirometry becomes more challenging as the size of the organism reduces. Additionally, respirometry can be costly and require significant experience and technical knowledge which may prohibit uptake in non-specialist/non-physiology labs. Thus, using equipment routine in most developmental/molecular biology laboratories, we measured glucose uptake in 96-h post fertilisation (hpf) zebrafish larvae and compared it to stop-flow respirometry measures of oxygen uptake to test whether glucose uptake was a suitable alternative measure of metabolic rate. A Passing-Bablok regression revealed that within a 95% limit of agreement, the rate of glucose uptake and the rate of oxygen uptake were equivalent as measures of metabolic rate in 96 hpf Danio rerio larvae. Thus, the methodology we outline here may be a useful alternative or a complementary method for assessing metabolic rate in small organisms. Rate of glucose uptake can be used as an alternative to oxygen uptake for assessing metabolic rate in small larval fish.
Collapse
|
6
|
Plein M, O'Brien KR, Holden MH, Adams MP, Baker CM, Bean NG, Sisson SA, Bode M, Mengersen KL, McDonald‐Madden E. Modeling total predation to avoid perverse outcomes from cat control in a data-poor island ecosystem. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2022; 36:e13916. [PMID: 35352431 PMCID: PMC9804458 DOI: 10.1111/cobi.13916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 12/22/2021] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Data hungry, complex ecosystem models are often used to predict the consequences of threatened species management, including perverse outcomes. Unfortunately, this approach is impractical in many systems, which have insufficient data to parameterize ecosystem interactions or reliably calibrate or validate such models. Here we demonstrate a different approach, using a minimum realistic model to guide decisions in data- and resource-scarce systems. We illustrate our approach with a case-study in an invaded ecosystem from Christmas Island, Australia, where there are concerns that cat eradication to protect native species, including the red-tailed tropicbird, could release meso-predation by invasive rats. We use biophysical constraints (metabolic demand) and observable parameters (e.g. prey preferences) to assess the combined cat and rat abundances which would threaten the tropicbird population. We find that the population of tropicbirds cannot be sustained if predated by 1607 rats (95% credible interval (CI) [103, 5910]) in the absence of cats, or 21 cats (95% CI [2, 82]) in the absence of rats. For every cat removed from the island, the bird's net population growth rate improves, provided that the rats do not increase by more than 77 individuals (95% CI [30, 174]). Thus, in this context, one cat is equivalent to 30-174 rats. Our methods are especially useful for on-the-ground predator control in the absence of knowledge of predator-predator interactions, to assess whether 1) the current abundance of predators threatens the prey population of interest, 2) managing one predator species alone is sufficient to protect the prey species given potential release of another predator, and 3) control of multiple predator species is needed to meet the conservation goal. Our approach demonstrates how to use limited information for maximum value in data-poor systems, by shifting the focus from predicting future trajectories, to identifying conditions which threaten the conservation goal. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Michaela Plein
- School of Earth and Environmental ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
- Centre for Biodiversity and Conservation ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
- Administration de la nature et des forêtsDiekirchLuxembourg
| | - Katherine R. O'Brien
- School of Chemical EngineeringUniversity of QueenslandSt LuciaQueenslandAustralia
| | - Matthew H. Holden
- Centre for Biodiversity and Conservation ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
- School of Biological SciencesUniversity of QueenslandBrisbaneQueenslandAustralia
- School of Mathematics and PhysicsUniversity of QueenslandBrisbaneQueenslandAustralia
| | - Matthew P. Adams
- School of Earth and Environmental ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
- Centre for Biodiversity and Conservation ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
- School of Chemical EngineeringUniversity of QueenslandSt LuciaQueenslandAustralia
- School of Mathematical SciencesQueensland University of TechnologyBrisbaneQueenslandAustralia
- ARC Centre of Excellence for Mathematical and Statistical FrontiersQueensland University of, TechnologyBrisbaneQueenslandAustralia
| | - Christopher M. Baker
- School of Mathematics and StatisticsThe University of MelbourneParkvilleVictoriaAustralia
- Melbourne Centre for Data ScienceThe University of MelbourneParkvilleVictoriaAustralia
- Centre of Excellence for Biosecurity Risk AnalysisThe University of MelbourneMelbourneVictoriaAustralia
| | - Nigel G. Bean
- School of Mathematical SciencesUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Research Council Centre of Excellence for Mathematical and Statistical FrontiersUniversity of AdelaideAdelaideSouth AustraliaAustralia
| | - Scott A. Sisson
- School of Mathematics and StatisticsUniversity of New South WalesSydneyNew South WalesAustralia
- UNSW Data Science HubUniversity of New SouthWales, SydneyNew South WalesAustralia
| | - Michael Bode
- School of Mathematical SciencesQueensland University of TechnologyBrisbaneQueenslandAustralia
| | - Kerrie L. Mengersen
- School of Mathematical SciencesQueensland University of TechnologyBrisbaneQueenslandAustralia
- ARC Centre of Excellence for Mathematical and Statistical FrontiersQueensland University of, TechnologyBrisbaneQueenslandAustralia
| | - Eve McDonald‐Madden
- School of Earth and Environmental ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
- Centre for Biodiversity and Conservation ScienceUniversity of QueenslandSt LuciaQueenslandAustralia
| |
Collapse
|
7
|
All-You-Can-Eat: Influence of Proximity to Maize Gardens on the Wild Diet and the Forest Activities of the Sebitoli Chimpanzee Community in Kibale National Park. Animals (Basel) 2022; 12:ani12070806. [PMID: 35405796 PMCID: PMC8996920 DOI: 10.3390/ani12070806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 03/11/2022] [Accepted: 03/18/2022] [Indexed: 12/16/2022] Open
Abstract
Simple Summary Understanding the resilience of primate populations to the threat of agricultural expansion is critical for effective conservation. Based on individual monitoring from morning to evening of wild chimpanzees in and around a protected area, we showed that the availability of maize at the forest edge had little effect on their activity budget by less resting and no impact on their wild diet and energy expenditure. In this area, large, caloric wild fruits are available year-round, and we observed no behavioral or dietary changes regarding wild resource availability either. Thus, the chimpanzees consume maize opportunistically as a bonus treat in their diet, and the presence of this nutritious resource does not seem to affect their role in seed dispersal and forest regeneration. Abstract Frugivorous primates have developed several strategies to deal with wild fruit scarcity, such as modifying their activity budget or enlarging their diet. Agricultural expansion threatens primate habitats and populations (e.g., disease transmission, agrochemical exposure), but it also increases crop feeding opportunities. We aimed at understanding whether maize presence close to the natural habitat of chimpanzees, a threatened species, would lead to significant behavioral modifications. We monitored 20 chimpanzees over 37 months in Kibale National Park, Uganda, with maize gardens at the forest edge. Based on focal nest-to-nest data, we analyzed their diet, activity budget, and energy balance depending on wild fruit and maize availability. We found that the Sebitoli area is a highly nutritive habitat for chimpanzees, with large and caloric wild fruits available all year long. The chimpanzees opportunistically consume maize and exploit it by resting less during maize season. However, no significant variation was found in daily paths and energy expenditures according to maize availability. No behavioral or energy modification was observed regarding wild resources either. Despite the availability of nutritious domestic resources, chimpanzees still exploit wild fruits and do not limit their movements. Thus, their contribution to seed dispersal and forest regeneration in this area is not affected.
Collapse
|
8
|
Reho JJ, Nakagawa P, Mouradian GC, Grobe CC, Saravia FL, Burnett CML, Kwitek AE, Kirby JR, Segar JL, Hodges MR, Sigmund CD, Grobe JL. Methods for the Comprehensive in vivo Analysis of Energy Flux, Fluid Homeostasis, Blood Pressure, and Ventilatory Function in Rodents. Front Physiol 2022; 13:855054. [PMID: 35283781 PMCID: PMC8914175 DOI: 10.3389/fphys.2022.855054] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/03/2022] [Indexed: 01/22/2023] Open
Abstract
Cardiovascular disease represents the leading cause of death in the United States, and metabolic diseases such as obesity represent the primary impediment to improving cardiovascular health. Rodent (mouse and rat) models are widely used to model cardiometabolic disease, and as a result, there is increasing interest in the development of accurate and precise methodologies with sufficiently high resolution to dissect mechanisms controlling cardiometabolic physiology in these small organisms. Further, there is great utility in the development of centralized core facilities furnished with high-throughput equipment configurations and staffed with professional content experts to guide investigators and ensure the rigor and reproducibility of experimental endeavors. Here, we outline the array of specialized equipment and approaches that are employed within the Comprehensive Rodent Metabolic Phenotyping Core (CRMPC) and our collaborating laboratories within the Departments of Physiology, Pediatrics, Microbiology & Immunology, and Biomedical Engineering at the Medical College of Wisconsin (MCW), for the detailed mechanistic dissection of cardiometabolic function in mice and rats. We highlight selected methods for the analysis of body composition and fluid compartmentalization, electrolyte accumulation and flux, energy accumulation and flux, physical activity, ingestive behaviors, ventilatory function, blood pressure, heart rate, autonomic function, and assessment and manipulation of the gut microbiota. Further, we include discussion of the advantages and disadvantages of these approaches for their use with rodent models, and considerations for experimental designs using these methods.
Collapse
Affiliation(s)
- John J. Reho
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Pablo Nakagawa
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Gary C. Mouradian
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Connie C. Grobe
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Fatima L. Saravia
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Colin M. L. Burnett
- Department of Internal Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA, United States
| | - Anne E. Kwitek
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States,Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI, United States
| | - John R. Kirby
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jeffrey L. Segar
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States,Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Matthew R. Hodges
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Curt D. Sigmund
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Justin L. Grobe
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, United States,Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, WI, United States,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, United States,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, United States,Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI, United States,*Correspondence: Justin L. Grobe,
| |
Collapse
|
9
|
Löffler MC, Betz MJ, Blondin DP, Augustin R, Sharma AK, Tseng YH, Scheele C, Zimdahl H, Mark M, Hennige AM, Wolfrum C, Langhans W, Hamilton BS, Neubauer H. Challenges in tackling energy expenditure as obesity therapy: From preclinical models to clinical application. Mol Metab 2021; 51:101237. [PMID: 33878401 PMCID: PMC8122111 DOI: 10.1016/j.molmet.2021.101237] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/31/2021] [Accepted: 04/13/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND A chronic imbalance of energy intake and energy expenditure results in excess fat storage. The obesity often caused by this overweight is detrimental to the health of millions of people. Understanding both sides of the energy balance equation and their counter-regulatory mechanisms is critical to the development of effective therapies to treat this epidemic. SCOPE OF REVIEW Behaviors surrounding ingestion have been reviewed extensively. This review focuses more specifically on energy expenditure regarding bodyweight control, with a particular emphasis on the organs and attractive metabolic processes known to reduce bodyweight. Moreover, previous and current attempts at anti-obesity strategies focusing on energy expenditure are highlighted. Precise measurements of energy expenditure, which consist of cellular, animal, and human models, as well as measurements of their translatability, are required to provide the most effective therapies. MAJOR CONCLUSIONS A precise understanding of the components surrounding energy expenditure, including tailored approaches based on genetic, biomarker, or physical characteristics, must be integrated into future anti-obesity treatments. Further comprehensive investigations are required to define suitable treatments, especially because the complex nature of the human perspective remains poorly understood.
Collapse
Affiliation(s)
- Mona C Löffler
- Cardio Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Matthias J Betz
- Department of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Basel, Switzerland
| | - Denis P Blondin
- Department of Medicine, Division of Neurology, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, QC, Canada
| | - Robert Augustin
- Cardio Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Anand K Sharma
- Institute of Food, Nutrition and Health, ETH Zürich, Schwerzenbach, Switzerland
| | - Yu-Hua Tseng
- Joslin Diabetes Center, Section on Integrative Physiology and Metabolism, Harvard Medical School, Boston, MA, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA
| | - Camilla Scheele
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Heike Zimdahl
- Cardio Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Michael Mark
- Cardio Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Anita M Hennige
- Therapeutic Area CardioMetabolism & Respiratory, Boehringer Ingelheim International GmbH, Biberach, Germany
| | - Christian Wolfrum
- Institute of Food, Nutrition and Health, ETH Zürich, Schwerzenbach, Switzerland
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, Department of Health Sciences and Technology, ETH Zürich, Switzerland
| | - Bradford S Hamilton
- Cardio Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Heike Neubauer
- Cardio Metabolic Diseases Research, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany.
| |
Collapse
|
10
|
Kaiyala KJ. Review of Measuring Metabolic Rates: A Manual for Scientists. Physiol Biochem Zool 2021. [DOI: 10.1086/714603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
11
|
Riedl RA, Burnett CML, Pearson NA, Reho JJ, Mokadem M, Edwards RA, Kindel TL, Kirby JR, Grobe JL. Gut Microbiota Represent a Major Thermogenic Biomass. FUNCTION (OXFORD, ENGLAND) 2021; 2:zqab019. [PMID: 33939772 PMCID: PMC8055641 DOI: 10.1093/function/zqab019] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 01/06/2023]
Abstract
Evidence supports various roles for microbial metabolites in the control of multiple aspects of host energy flux including feeding behaviors, digestive efficiency, and energy expenditure, but few studies have quantified the energy utilization of the biomass of the gut microbiota itself. Because gut microbiota exist in an anoxic environment, energy flux is expected to be anaerobic; unfortunately, commonly utilized O2/CO2 respirometry-based approaches are unable to detect anaerobic energy flux. To quantify the contribution of the gut microbial biomass to whole-animal energy flux, we examined the effect of surgical reduction of gut biomass in C57BL/6J mice via cecectomy and assessed energy expenditure using methods sensitive to anaerobic flux, including bomb and direct calorimetry. First, we determined that cecectomy caused an acceleration of weight gain over several months due to a reduction in combined total host plus microbial energy expenditure, as reflected by an increase in energy efficiency (ie, weight gained per calorie absorbed). Second, we determined that under general anesthesia, cecectomy caused immediate changes in heat dissipation that were significantly modified by short-term pretreatment with dietary or pharmaceutical interventions known to modify the microbiome, and confirmed that these effects were undetectable by respirometry. We conclude that while the cecum only contributes approximately 1% of body mass in the mouse, this organ contributes roughly 8% of total resting energy expenditure, that this contribution is predominantly anaerobic, and that the composition and abundance of the cecal microbial contents can significantly alter its contribution to energy flux.
Collapse
Affiliation(s)
- Ruth A Riedl
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Colin M L Burnett
- Department of Internal Medicine, Division of Cardiology, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Nicole A Pearson
- Department of Laboratory Medicine and Pathology/Proteomics, Mayo Clinic, Rochester, MN, USA
| | - John J Reho
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA,Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Mohamad Mokadem
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Robert A Edwards
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Tammy L Kindel
- Department of Surgery, Medical College of Wisconsin, Milwaukee, WI, USA,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA
| | - John R Kirby
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA,Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, USA,Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, WI, USA,Center for Microbiome Research, Medical College of Wisconsin, Milwaukee, WI, USA,Address correspondence to J.L.G. (e-mail: ), J.R.K. (e-mail: )
| | - Justin L Grobe
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA,Comprehensive Rodent Metabolic Phenotyping Core, Medical College of Wisconsin, Milwaukee, WI, USA,Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI, USA,Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, USA,Address correspondence to J.L.G. (e-mail: ), J.R.K. (e-mail: )
| |
Collapse
|
12
|
Sokolova I. Bioenergetics in environmental adaptation and stress tolerance of aquatic ectotherms: linking physiology and ecology in a multi-stressor landscape. J Exp Biol 2021; 224:224/Suppl_1/jeb236802. [PMID: 33627464 DOI: 10.1242/jeb.236802] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Energy metabolism (encompassing energy assimilation, conversion and utilization) plays a central role in all life processes and serves as a link between the organismal physiology, behavior and ecology. Metabolic rates define the physiological and life-history performance of an organism, have direct implications for Darwinian fitness, and affect ecologically relevant traits such as the trophic relationships, productivity and ecosystem engineering functions. Natural environmental variability and anthropogenic changes expose aquatic ectotherms to multiple stressors that can strongly affect their energy metabolism and thereby modify the energy fluxes within an organism and in the ecosystem. This Review focuses on the role of bioenergetic disturbances and metabolic adjustments in responses to multiple stressors (especially the general cellular stress response), provides examples of the effects of multiple stressors on energy intake, assimilation, conversion and expenditure, and discusses the conceptual and quantitative approaches to identify and mechanistically explain the energy trade-offs in multiple stressor scenarios, and link the cellular and organismal bioenergetics with fitness, productivity and/or ecological functions of aquatic ectotherms.
Collapse
Affiliation(s)
- Inna Sokolova
- Marine Biology Department, Institute of Biological Sciences, University of Rostock, 18059 Rostock, Germany .,Department of Maritime Systems, Interdisciplinary Faculty, University of Rostock, 18059 Rostock, Germany
| |
Collapse
|
13
|
Herbert E, Ouerdane H, Lecoeur P, Bels V, Goupil C. Thermodynamics of Animal Locomotion. PHYSICAL REVIEW LETTERS 2020; 125:228102. [PMID: 33315423 DOI: 10.1103/physrevlett.125.228102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/26/2020] [Indexed: 06/12/2023]
Abstract
Muscles are biological actuators extensively studied in the frame of Hill's classic empirical model as isolated biomechanical entities, which hardly applies to a living organism subjected to physiological and environmental constraints. Here we elucidate the overarching principle of a living muscle action for locomotion, considering it from the thermodynamic viewpoint as an assembly of actuators (muscle units) connected in parallel, operating via chemical-to-mechanical energy conversion under mixed (potential and flux) boundary conditions. Introducing the energy cost of effort as the generalization of the well-known oxygen cost of transport in the frame of our compact locally linear nonequilibrium thermodynamics model, we analyze oxygen consumption measurement data from a documented experiment on energy cost management and optimization by horses moving at three different gaits. Horses adapt to a particular gait by mobilizing a nearly constant number of muscle units minimizing waste production per unit distance covered; this number significantly changes during transition between gaits. The mechanical function of the animal is therefore determined both by its own thermodynamic characteristics and by the metabolic operating point of the locomotor system.
Collapse
Affiliation(s)
- E Herbert
- Laboratoire Interdisciplinaire des Energies de Demain (LIED), CNRS UMR 8236, Université Paris Diderot, 5 Rue Thomas Mann, 75013 Paris, France
| | - H Ouerdane
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, 3 Nobel Street, Skolkovo, Moscow Region 121205, Russia
| | - Ph Lecoeur
- Center for Nanoscience and Nanotechnology (C2N), CNRS, Université Paris-Saclay, 91120 Palaiseau, France
| | - V Bels
- Institut de Systématique, Evolution, Biodiversité, ISYEB, CNRS/MNHN/EPHE/UA UMR 7205, Muséum national d'Histoire naturelle, Sorbonne Universités, 45 rue Buffon, 75005 Paris, France
| | - Ch Goupil
- Laboratoire Interdisciplinaire des Energies de Demain (LIED), CNRS UMR 8236, Université Paris Diderot, 5 Rue Thomas Mann, 75013 Paris, France
| |
Collapse
|
14
|
Ono-Moore KD, Rutkowsky JM, Pearson NA, Williams DK, Grobe JL, Tolentino T, Lloyd KCK, Adams SH. Coupling of energy intake and energy expenditure across a temperature spectrum: impact of diet-induced obesity in mice. Am J Physiol Endocrinol Metab 2020; 319:E472-E484. [PMID: 32691631 PMCID: PMC7509245 DOI: 10.1152/ajpendo.00041.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Obesity and its metabolic sequelae are implicated in dysfunction of the somatosensory, sympathetic, and hypothalamic systems. Because these systems contribute to integrative regulation of energy expenditure (EE) and energy intake (EI) in response to ambient temperature (Ta) changes, we hypothesized that diet-induced obesity (DIO) disrupts Ta-associated EE-EI coupling. C57BL/6N male mice were fed a high-fat diet (HFD; 45% kcal) or low-fat diet (LFD; 10% kcal) for ∼9.5 wk; HFD mice were then split into body weight (BWT) quartiles (n = 8 each) to study DIO-low gainers (Q1) versus -high gainers (Q4). EI and indirect calorimetry (IC) were measured over 3 days each at 10°C, 20°C, and 30°C. Responses did not differ between LFD, Q1, and Q4; EI and BWT-adjusted EE increased rapidly when transitioning toward 20°C and 10°C. In all groups, EI at 30°C was not reduced despite lower EE, resulting in positive energy balance and respiratory exchange ratios consistent with increased de novo lipogenesis, energy storage, and relative hyperphagia. We conclude that 1) systems controlling Ta-dependent acute EI/EE coupling remained intact in obese mice and 2) rapid coupling of EI/EE at cooler temperatures is an important adaptation to maintain energy stores and defend body temperature, but less critical at thermoneutrality. A post hoc analysis using digestible EI plus IC-calculated EE suggests that standard IC assumptions for EE calculation require further validation in the setting of DIO. The experimental paradigm provides a platform to query the hypothalamic, somatosensory, and sympathetic mechanisms that drive Ta-associated EI/EE coupling.
Collapse
Affiliation(s)
| | - Jennifer M Rutkowsky
- Department of Molecular Biosciences, UC Davis School of Veterinary Medicine, University of California, Davis, California
- Mouse Metabolic Phenotyping Center, University of California, Davis, California
| | - Nicole A Pearson
- Department of Pharmacology, University of Iowa, Carver College of Medicine, Iowa City, Iowa
| | - D Keith Williams
- Arkansas Children's Nutrition Center, Little Rock, Arkansas
- Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Justin L Grobe
- Department of Physiology and Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Todd Tolentino
- Mouse Metabolic Phenotyping Center, University of California, Davis, California
| | - K C Kent Lloyd
- Mouse Metabolic Phenotyping Center, University of California, Davis, California
- Department of Surgery, School of Medicine, University of California, Davis, California
| | - Sean H Adams
- Arkansas Children's Nutrition Center, Little Rock, Arkansas
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| |
Collapse
|
15
|
Mast MH. Claims of anomalously long fasting: An assessment of the evidence from investigated cases. Explore (NY) 2020; 16:287-296. [PMID: 32739103 DOI: 10.1016/j.explore.2020.05.015] [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: 05/30/2019] [Revised: 05/16/2020] [Accepted: 05/24/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND Throughout history and to the present day, there have been reports of people claiming inedia, i.e., an anomalous long-term abstinence from food or from food and fluid. Some were isolated and monitored and their abstinences confirmed. This raises the question of whether there may be an anomaly with wide implications that science has overlooked. On the other hand, there have been cases of exposed fraud. The reports on the studies are scattered and it can be difficult to judge their rigor and the strength and implications of their evidence. A critical evaluation seems useful. OBJECTIVES The objectives were to obtain an overview of investigated cases of claimed inedia, to assess the anomaly of the claims and study results, to assess the quality of the studies, and to identify deception methods to inform future safeguards. METHOD I developed criteria for differentiating normal from anomalous nutrition and fasting and for assessing the quality of inedia studies. Studies found through a systematic search were then assessed and the features of cases of fraud extracted. RESULTS 47 eligible investigations of 38 claimants were found. Out of the 38 cases, results were assessed as (seemingly) anomalous in 11, with nine cases of monitored food and fluid deprivation ranging from 14 to 68 days (median 28 days), and two cases of food deprivation for 365 and 411 days. In 17 cases, anomaly was assessed as not confirmed due to issues with study design or reporting. Fraud was established in 10 cases. Deception methods were creative. Post-1900 studies were also assessed for quality. Quality was not considered adequate in any. CONCLUSIONS I consider the evidential status of inedia unconfirmed as no assessed study had both anomalous findings and impeccable quality. However, quality was often downgraded due to reporting issues and it cannot be concluded in reverse that all claimants with anomalous results were able to deceive the investigators. The results of many studies are curious and demand further research. The conducted analysis provides guidance for improving rigor and transparency in future studies.
Collapse
|
16
|
Ramsay DS, Kaiyala KJ, Woods SC. Individual differences in biological regulation: Predicting vulnerability to drug addiction, obesity, and other dysregulatory disorders. Exp Clin Psychopharmacol 2020; 28:388-403. [PMID: 32338936 PMCID: PMC8389185 DOI: 10.1037/pha0000371] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Physiological regulation is so fundamental to survival that natural selection has greatly favored the evolution of robust regulatory systems that use both reactive and preemptive responses to mitigate the disruptive impact of biological and environmental challenges on physiological function. In good health, robust regulatory systems provide little insight into the typically hidden complex array of sensor-effector interactions that accomplish successful regulation. Numerous health disorders have been traced to defective regulatory mechanisms, and generations of scientists have worked to discover ways to correct these defects and restore normal physiological function. Despite progress, numerous chronic health disorders remain resistant to treatment, and indeed for some disorders the incidence is increasing. We propose that an individual's susceptibility to acquire certain persistent dysregulatory disorders can be traced to interindividual variation in how that individual's regulatory system responds to challenges. Preexisting reliable individual differences among regulatory systems are typically unrecognized until appropriate regulatory challenges (e.g., exposure to a drug of abuse) lead to dysregulation (e.g., drug addiction). Specific characteristics of an individual's regulatory responsiveness may include etiological factors that participate in the acquisition, escalation and maintenance of health disorders characterized by dysregulation. By appropriately challenging a healthy individual's regulatory systems to identify its underlying characteristics, it is possible to ascertain whether an individual has an elevated risk for acquiring a dysregulated health condition and thereby enable strategies designed to prevent, rather than treat, the condition. This model is applied to drug addiction, and in addition we relate this approach to other dysregulated conditions such as obesity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
Collapse
Affiliation(s)
- Douglas S. Ramsay
- Department of Oral Health Sciences, University of Washington
- Department of Orthodontics, University of Washington
- Department of Pediatric Dentistry, University of Washington
| | - Karl J. Kaiyala
- Department of Oral Health Sciences, University of Washington
| | - Stephen C. Woods
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati Medical Center
| |
Collapse
|
17
|
Kumari S, Fagodiya RK, Hiloidhari M, Dahiya RP, Kumar A. Methane production and estimation from livestock husbandry: A mechanistic understanding and emerging mitigation options. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 709:136135. [PMID: 31927428 DOI: 10.1016/j.scitotenv.2019.136135] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 12/11/2019] [Accepted: 12/13/2019] [Indexed: 06/10/2023]
Abstract
Globally, livestock is an important contributor to methane (CH4) emissions. This paper reviewed the various CH4 measurement and estimation techniques and mitigation approaches for the livestock sector. Two approaches for enteric livestock CH4 emission estimation are the top-down and bottom-up. The combination of both could further improve our understanding of enteric CH4 emission and possible mitigation measures. We discuss three mitigation approaches: reducing emissions, avoiding emissions, and enhancing the removal of emissions from livestock. Dietary management, livestock management, and breeding management are viable reducing emissions pathways. Dietary manipulation is easily applicable and can bring an immediate response. Economic incentive policies can help the livestock farmers to opt for diet, breeding, and livestock management mitigation approaches. Carbon pricing creates a better option to achieve reduction targets in a given period. A combination of carbon pricing, feeding management, breeding management, and livestock management is more feasible and sustainable CH4 emissions mitigation strategy rather than a single approach.
Collapse
Affiliation(s)
- Shilpi Kumari
- Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi - 110 016, India.
| | - R K Fagodiya
- Division of Irrigation and Drainage Engineering, ICAR - Central Soil Salinity Research Institute, Karnal - 132 001, India
| | - Moonmoon Hiloidhari
- IDP in Climate Studies, Indian Institute of Technology Bombay, Mumbai - 400 076, India
| | - R P Dahiya
- Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi - 110 016, India
| | - Amit Kumar
- Department of Botany, Dayalbagh Educational Institute, Agra - 282 005, India
| |
Collapse
|
18
|
Do we need race-specific resting metabolic rate prediction equations? Nutr Diabetes 2019; 9:21. [PMID: 31358726 PMCID: PMC6662665 DOI: 10.1038/s41387-019-0087-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 04/10/2019] [Accepted: 06/13/2019] [Indexed: 12/12/2022] Open
Abstract
Background Resting metabolic rate (RMR) is a key determinant of daily caloric needs. Respirometry, a form of indirect calorimetry (IC), is considered one of the most accurate methods to measure RMR in clinical and research settings. It is impractical to measure RMR by IC in routine clinical practice; therefore, several formulas are used to predict RMR. In this study, we sought to determine the accuracy of these formulas in determining RMR and assess additional factors that may determine RMR. Methods We measured RMR in 114 subjects (67% female, 30% African American [AA]) using IC. Along with standard anthropometrics, dual-energy X-ray absorptiometry was used to obtain fat-free mass(FFM) and total fat mass. Measured RMR (mRMR) by respirometry was compared with predicted RMR (pRMR) generated by Mifflin–St.Joer, Cunningham, and Harris–Benedict (HB) equations. Linear regression models were used to determine factors affecting mRMR. Results Mean age, BMI, and mRMR of subjects were 46 ± 16 years (mean ± SD), 35 ± 10 kg/m2, and 1658 ± 391 kcal/day, respectively. After adjusting for age, gender, and anthropometrics, the two largest predictors of mRMR were race (p < 0.0001) and FFM (p < 0.0001). For every kg increase in FFM, RMR increased by 28 kcal/day (p < 0.0001). AA race was associated with 144 kcal/day (p < 0.0001) decrease in mRMR. The impact of race on mRMR was mitigated by adding in truncal FFM to the model. When using only clinically measured variables to predict mRMR, we found race, hip circumference, age, gender, and weight to be significant predictors of mRMR (p < 0.005). Mifflin–St.Joer and HB equations that use just age, gender, height, and weight overestimated kcal expenditure in AA by 138 ± 148 and 242 ± 164 (p < 0.0001), respectively. Conclusion We found that formulas utilizing height, weight, gender, and age systematically overestimate mRMR and hence predict higher calorie needs among AA. The lower mRMR in AA could be related to truncal fat-free mass representing the activity of metabolically active intraabdominal organs.
Collapse
|
19
|
Soto JE, Burnett CM, Eyck PT, Abel ED, Grobe JL. Comparison of the Effects of High-Fat Diet on Energy Flux in Mice Using Two Multiplexed Metabolic Phenotyping Systems. Obesity (Silver Spring) 2019; 27:793-802. [PMID: 30938081 PMCID: PMC6478533 DOI: 10.1002/oby.22441] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 01/18/2019] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Multiplexed metabolic phenotyping systems are available from multiple commercial vendors, and each system includes unique design features. Although expert opinion supports strengths and weaknesses of each design, empirical data from carefully controlled studies to test the biological impact of design differences are lacking. METHODS Wild-type C57BL/6J mice of both sexes underwent phenotyping in OxyMax (Columbus Instruments International) and Promethion (Sable Systems International) systems located within the same room of a newly constructed animal research facility in a crossover design study. Phenotypes were examined under chow (2920×)-fed conditions and again after 4 weeks of 60% high-fat diet (D12492) feeding. RESULTS Food intake, physical activity, and respiratory gas exchange data significantly diverged between systems, depending upon sex of animals and diet supplied. Estimates of energy expenditure based on gas exchange in both systems accounted for a fraction of consumed calories that was greater in males than females. CONCLUSIONS Design differences quantitatively impact the assessment of metabolic end points and thus the qualitative interpretation of various interventions. Importantly, current multiplexed systems remain blind to multiple additional end points, including digestive efficiency and selected forms of energy flux (nitrogenous, anaerobic, etc.), that account for a physiologically and/or pathophysiologically significant fraction of total energy flux.
Collapse
Affiliation(s)
- Jamie E. Soto
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
- Department of Fraternal Order of Eagles’ Diabetes Research Center, University of Iowa, Iowa City, IA 52242
| | - Colin M.L. Burnett
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
- Department of Pharmacology, University of Iowa, Iowa City, IA 52242
| | - Patrick Ten Eyck
- Department of Institute for Clinical and Translational Science, University of Iowa, Iowa City, IA 52242
| | - E. Dale Abel
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
- Department of Fraternal Order of Eagles’ Diabetes Research Center, University of Iowa, Iowa City, IA 52242
- Department of Obesity Research & Education Initiative, University of Iowa, Iowa City, IA 52242
- Department of Abboud Cardiovascular Research Center, University of Iowa, Iowa City, IA 52242
| | - Justin L. Grobe
- Department of Pharmacology, University of Iowa, Iowa City, IA 52242
- Department of Fraternal Order of Eagles’ Diabetes Research Center, University of Iowa, Iowa City, IA 52242
- Department of Obesity Research & Education Initiative, University of Iowa, Iowa City, IA 52242
- Department of UIHC Center for Hypertension Research, University of Iowa, Iowa City, IA 52242
- Department of Abboud Cardiovascular Research Center, University of Iowa, Iowa City, IA 52242
- Iowa Neuroscience Institute, University of Iowa, Iowa City, IA 52242
| |
Collapse
|
20
|
Ruiz T, Bec A, Danger M, Koussoroplis AM, Aguer JP, Morel JP, Morel-Desrosiers N. A microcalorimetric approach for investigating stoichiometric constraints on the standard metabolic rate of a small invertebrate. Ecol Lett 2018; 21:1714-1722. [DOI: 10.1111/ele.13137] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/07/2018] [Accepted: 07/20/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Thomas Ruiz
- Université Clermont Auvergne; CNRS; LMGE; Clermont-Ferrand F-63000 France
| | - Alexandre Bec
- Université Clermont Auvergne; CNRS; LMGE; Clermont-Ferrand F-63000 France
| | | | | | - Jean-Pierre Aguer
- Université Clermont Auvergne; CNRS; LMGE; Clermont-Ferrand F-63000 France
| | - Jean-Pierre Morel
- Université Clermont Auvergne; CNRS; LMGE; Clermont-Ferrand F-63000 France
| | | |
Collapse
|
21
|
Spierling SR, Kreisler AD, Williams CA, Fang SY, Pucci SN, Kines KT, Zorrilla EP. Intermittent, extended access to preferred food leads to escalated food reinforcement and cyclic whole-body metabolism in rats: Sex differences and individual vulnerability. Physiol Behav 2018; 192:3-16. [PMID: 29654812 PMCID: PMC6019212 DOI: 10.1016/j.physbeh.2018.04.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/31/2018] [Accepted: 04/01/2018] [Indexed: 10/17/2022]
Abstract
Compulsive binge eating is a hallmark of binge eating disorder and bulimia nervosa and is implicated in some obesity cases. Eating disorders are sexually dimorphic, with females more often affected than males. Animal models of binge-like eating based on intermittent access to palatable food exist; but, little is known regarding sex differences or individual vulnerability in these models with respect to the reinforcing efficacy of food, the development of compulsive- and binge-like eating, or associated changes in whole-body metabolism or body composition. Adolescent male (n = 24) and female (n = 32) Wistar rats were maintained on chow or a preferred, high-sucrose, chocolate-flavored diet in continuous or intermittent, extended access conditions. Body weight and composition, intake, fixed- and progressive-ratio operant self-administration, and whole body energy expenditure and respiratory exchange ratios were measured across an 11-week study period. Subgroup analyses were conducted to differentiate compulsive-like "high responder" intermittent access rats that escalated to extreme progressive-ratio self-administration performance vs. more resistant "low responders." Female rats had greater reinforcing efficacy of food than males in all diet conditions and were more often classified as "high responders". In both sexes, rats with intermittent access showed cycling of fuel substrate utilization and whole-body energy expenditure. Further, "high-responding" intermittent access female rats had especially elevated respiratory exchange ratios, indicating a fat-sparing phenotype. Future studies are needed to better understand the molecular and neurobiological basis of the sex and individual differences we have observed in rats and their translational impact for humans with compulsive, binge eating disorders.
Collapse
Affiliation(s)
- Samantha R Spierling
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA.
| | - Alison D Kreisler
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Casey A Williams
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Savannah Y Fang
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Sarah N Pucci
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Kelsey T Kines
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA
| | - Eric P Zorrilla
- Department of Neuroscience, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA, USA.
| |
Collapse
|
22
|
Lin BS, Wang LY, Hwang YT, Chiang PY, Chou WJ. Depth-Camera-Based System for Estimating Energy Expenditure of Physical Activities in Gyms. IEEE J Biomed Health Inform 2018; 23:1086-1095. [PMID: 29993562 DOI: 10.1109/jbhi.2018.2840834] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Energy expenditure (EE) monitoring is crucial to tracking physical activity (PA). Accurate EE monitoring may help people engage in adequate activity and therefore avoid obesity and reduce the risk of chronic diseases. This study proposes a depth-camera-based system for EE estimation of PA in gyms. Most previous studies have used inertial measurement units for EE estimation. By contrast, the proposed system can be used to conveniently monitor subjects' treadmill workouts in gyms without requiring them to wear any devices. A total of 21 subjects were recruited for the experiment. Subjects' skeletal data acquired using the depth camera and oxygen consumption data simultaneously obtained using the K4b2 device were used to establish an EE predictive model. To obtain a robust EE estimation model, depth cameras were placed in the side view, rear side view, and rear view. A comparison of five different predictive models and these three camera locations showed that the multilayer perceptron model was the best predictive model and that placing the camera in the rear view provided the best EE estimation performance. The measured and predicted metabolic equivalents of task exhibited a strong positive correlation, with r = 0.94 and coefficient of determination r2 = 0.89. Furthermore, the mean absolute error was 0.61 MET, mean squared error was 0.67 MET, and root mean squared error was 0.76 MET. These results indicate that the proposed system is handy and reliable for monitoring user's EE when performing treadmill workouts.
Collapse
|
23
|
Silva VRR, Katashima CK, Lenhare L, Silva CGB, Morari J, Camargo RL, Velloso LA, Saad MA, da Silva ASR, Pauli JR, Ropelle ER. Chronic exercise reduces hypothalamic transforming growth factor-β1 in middle-aged obese mice. Aging (Albany NY) 2018; 9:1926-1940. [PMID: 28854149 PMCID: PMC5611986 DOI: 10.18632/aging.101281] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Accepted: 08/25/2017] [Indexed: 12/23/2022]
Abstract
Obesity and aging are associated with hypothalamic inflammation, hyperphagia and abnormalities in the thermogenesis control. It has been demonstrated that the association between aging and obesity induces hypothalamic inflammation and metabolic disorders, at least in part, through the atypical hypothalamic transforming growth factor-β (TGF-β1). Physical exercise has been used to modulate several metabolic parameters. Thus, the aim of this study was to evaluate the impact of chronic exercise on TGF-β1 expression in the hypothalamus of Middle-Aged mice submitted to a one year of high-fat diet (HFD) treatment. We observed that long-term of HFD-feeding induced hypothalamic TGF-β1 accumulation, potentiated the hypothalamic inflammation, body weight gain and defective thermogenesis of Middle-Aged mice when compared to Middle-Aged animals fed on chow diet. As expected, chronic exercise induced negative energy balance, reduced food consumption and increasing the energy expenditure, which promotes body weight loss. Interestingly, exercise training reduced the TGF-β1 expression and IkB-α ser32 phosphorylation in the hypothalamus of Middle-Aged obese mice. Taken together our study demonstrated that chronic exercise suppressed the TGF-β1/IkB-α axis in the hypothalamus and improved the energy homeostasis in an animal model of obesity-associated to aging.
Collapse
Affiliation(s)
- Vagner R R Silva
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Carlos K Katashima
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Luciene Lenhare
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Carla G B Silva
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Joseane Morari
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas, 1308-970, Brazil
| | - Rafael L Camargo
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Licio A Velloso
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas, 1308-970, Brazil
| | - Mario A Saad
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Adelino S R da Silva
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, USP, School of Physical Education and Sport of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Jose Rodrigo Pauli
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,CEPECE - Research Center of Sport Sciences, School of Applied Sciences, University of Campinas, Limeira, SP, Brazil
| | - Eduardo Rochete Ropelle
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil.,CEPECE - Research Center of Sport Sciences, School of Applied Sciences, University of Campinas, Limeira, SP, Brazil
| |
Collapse
|
24
|
Concentration-related metabolic rate and behavioral thermoregulatory adaptations to serial administrations of nitrous oxide in rats. PLoS One 2018; 13:e0194794. [PMID: 29672605 PMCID: PMC5909668 DOI: 10.1371/journal.pone.0194794] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 03/10/2018] [Indexed: 11/19/2022] Open
Abstract
Background Initial administration of ≥60% nitrous oxide (N2O) to rats evokes hypothermia, but after repeated administrations the gas instead evokes hyperthermia. This sign reversal is driven mainly by increased heat production. To determine whether rats will behaviorally oppose or assist the development of hyperthermia, we previously performed thermal gradient testing. Inhalation of N2O at ≥60% causes rats to select cooler ambient temperatures both during initial administrations and during subsequent administrations in which the hyperthermic state exists. Thus, an available behavioral response opposes (but does not completely prevent) the acquired hyperthermia that develops over repeated high-concentration N2O administrations. However, recreational and clinical uses of N2O span a wide range of concentrations. Therefore, we sought to determine the thermoregulatory adaptations to chronic N2O administration over a wide range of concentrations. Methods This study had two phases. In the first phase we adapted rats to twelve 3-h N2O administrations at either 0%, 15%, 30%, 45%, 60% or 75% N2O (n = 12 per group); outcomes were core temperature (via telemetry) and heat production (via respirometry). In the second phase, we used a thermal gradient (range 8°C—38°C) to assess each adapted group’s thermal preference, core temperature and locomotion on a single occasion during N2O inhalation at the assigned concentration. Results In phase 1, repeated N2O administrations led to dose related hyperthermic and hypermetabolic states during inhalation of ≥45% N2O compared to controls (≥ 30% N2O compared to baseline). In phase 2, rats in these groups selected cooler ambient temperatures during N2O inhalation but still developed some hyperthermia. However, a concentration-related increase of locomotion was evident in the gradient, and theoretical calculations and regression analyses both suggest that locomotion contributed to the residual hyperthermia. Conclusions Acquired N2O hyperthermia in rats is remarkably robust, and occurs even despite the availability of ambient temperatures that might fully counter the hyperthermia. Increased locomotion in the gradient may contribute to hyperthermia. Our data are consistent with an allostatic dis-coordination of autonomic and behavioral thermoregulatory mechanisms during drug administration. Our results have implications for research on N2O abuse as well as research on the role of allostasis in drug addiction.
Collapse
|
25
|
Abstract
PURPOSE OF REVIEW The influence of gut bacteria upon host physiology is increasingly recognized, but mechanistic links are lacking. Diseases of energetic imbalance such as obesity and diabetes represent major risk factors for cardiovascular diseases such as hypertension. Thus, here, we review current mechanistic contributions of the gut microbiota to host energetics. RECENT FINDINGS Gut bacteria generate a multitude of small molecules which can signal to host tissues within and beyond the gastrointestinal tract to influence host physiology, and gut bacteria can also influence host digestive efficiency by altering the bioavailability of polysaccharides, yet the quantitative energetic effects of these processes remain unclear. Recently, our team has demonstrated that gut bacteria constitute a major anaerobic thermogenic biomass, which can quantitatively account for obesity. Quantitative understanding of the mechanisms by which gut bacteria influence energy homeostasis may ultimately inform the relationship between gut bacteria and cardiovascular dysfunction.
Collapse
|
26
|
Empirical Examinations of Effects of Three-Level Green Exercise on Engagement with Nature and Physical Activity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15020375. [PMID: 29470447 PMCID: PMC5858444 DOI: 10.3390/ijerph15020375] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/28/2018] [Accepted: 02/07/2018] [Indexed: 12/04/2022]
Abstract
Green exercise can be classified into three levels based on engagement with nature. Although this classification was proposed more than a decade ago, few studies have investigated it since. The present study examined the effects of green exercise levels on engagement with nature and physical activity (PA) through a field experiment. A questionnaire was distributed to 95 students from a technology university in Central Taiwan to measure their level of engagement with nature in people-environment transactions, while their PA was measured using three instruments. In addition, because social interaction may distract individual attention from activities or their environments, the present study incorporated the presence of partners as a control variable. The results revealed that (1) engagement with nature and PA significantly differed between the levels of green exercise, and the higher the level of green exercise participated in, the greater the level of engagement with nature; and (2) although the presence of partners did not influence the level of engagement with nature, it significantly affected the level of PA.
Collapse
|
27
|
Silva VRR, Katashima CK, Bueno Silva CG, Lenhare L, Micheletti TO, Camargo RL, Ghezzi AC, Camargo JA, Assis AM, Tobar N, Morari J, Razolli DS, Moura LP, Pauli JR, Cintra DE, Velloso LA, Saad MJA, Ropelle ER. Hypothalamic S1P/S1PR1 axis controls energy homeostasis in Middle-Aged Rodents: the reversal effects of physical exercise. Aging (Albany NY) 2017; 9:142-155. [PMID: 28039439 PMCID: PMC5310661 DOI: 10.18632/aging.101138] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 11/29/2016] [Indexed: 02/06/2023]
Abstract
Recently, we demonstrated that the hypothalamic S1PR1/STAT3 axis plays a critical role in the control of food consumption and energy expenditure in rodents. Here, we found that reduction of hypothalamic S1PR1 expression occurs in an age-dependent manner, and was associated with defective thermogenic signaling and weight gain. To address the physiological relevance of these findings, we investigated the effects of chronic and acute exercise on the hypothalamic S1PR1/STAT3 axis. Chronic exercise increased S1PR1 expression and STAT3 phosphorylation in the hypothalamus, restoring the anorexigenic and thermogenic signals in middle-aged mice. Acutely, exercise increased sphingosine-1-phosphate (S1P) levels in the cerebrospinal fluid (CSF) of young rats, whereas the administration of CSF from exercised young rats into the hypothalamus of middle-aged rats at rest was sufficient to reduce the food intake. Finally, the intracerebroventricular (ICV) administration of S1PR1 activators, including the bioactive lipid molecule S1P, and pharmacological S1PR1 activator, SEW2871, induced a potent STAT3 phosphorylation and anorexigenic response in middle-aged rats. Overall, these results suggest that hypothalamic S1PR1 is important for the maintenance of energy balance and provide new insights into the mechanism by which exercise controls the anorexigenic and thermogenic signals in the central nervous system during the aging process.
Collapse
Affiliation(s)
- Vagner Ramon Rodrigues Silva
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | | | - Carla G Bueno Silva
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Luciene Lenhare
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | | | | | - Ana Carolina Ghezzi
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | | | | | - Natalia Tobar
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Joseane Morari
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Daniela S Razolli
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | | | - José Rodrigo Pauli
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil.,CEPECE - Research Center of Sport Sciences, School of Applied Sciences, University of Campinas, Limeira, SP, Brazil
| | | | - Lício Augusto Velloso
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil.,Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas, 1308-970, Brazil
| | - Mario J A Saad
- Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil
| | - Eduardo Rochete Ropelle
- School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Department of Internal Medicine, University of Campinas, Campinas, SP, Brazil.,CEPECE - Research Center of Sport Sciences, School of Applied Sciences, University of Campinas, Limeira, SP, Brazil.,Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas, 1308-970, Brazil
| |
Collapse
|
28
|
Gordon CJ. The mouse thermoregulatory system: Its impact on translating biomedical data to humans. Physiol Behav 2017; 179:55-66. [PMID: 28533176 PMCID: PMC6196327 DOI: 10.1016/j.physbeh.2017.05.026] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 05/04/2017] [Accepted: 05/18/2017] [Indexed: 01/01/2023]
Abstract
The laboratory mouse has become the predominant test species in biomedical research. The number of papers that translate or extrapolate data from mouse to human has grown exponentially since the year 2000. There are many physiological and anatomical factors to consider in the process of extrapolating data from one species to another. Body temperature is, of course, a critical determinant in extrapolation because it has a direct impact on metabolism, cardiovascular function, drug efficacy, pharmacokinetics of toxins and drugs, and many other effects. While most would consider the thermoregulatory system of mice to be sufficiently stable and predictable as to not be a cause for concern, the thermal physiology of mice does in fact present unique challenges to the biomedical researcher. A variable and unstable core temperature, high metabolic rate, preference for warm temperatures, large surface area: body mass ratio, and high rate of thermal conductance, are some of the key factors of mice that can affect the interpretation and translation of data to humans. It is the intent of this brief review to enlighten researchers studying interspecies translation of biomedical data on the salient facets of the mouse thermal physiology and show how extrapolation in fields such as physiology, psychology, nutrition, pharmacology, toxicology, and pathology.
Collapse
Affiliation(s)
- Christopher J Gordon
- Toxicity Assessment Division, National Health Effects and Environmental Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, United States.
| |
Collapse
|
29
|
Han KT, Wang PC. Validity of Research-Grade Actigraphy Unit for Measuring Exercise Intensity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:E511. [PMID: 28489046 PMCID: PMC5451962 DOI: 10.3390/ijerph14050511] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 04/14/2017] [Accepted: 05/01/2017] [Indexed: 11/25/2022]
Abstract
This study was conducted in a free-living setting to investigate the measurement validity of a research-based actigraph for strolling and jogging, and to provide a reference for actual practice and research. Because inadequate physical activity (PA) or sedentary lifestyle has become the fourth leading risk factor for mortality worldwide, many countries have been vigorously promoting the concept of "active living", and the public has been investing greater effort into intensifying their PA. Although research-grade actigraphs have been widely applied to evaluate PA in routine environments, the measurement results may not accurately reflect the wearers' PA. Unlike most relevant research, which is conducted in well-controlled laboratory environments, the present study was implemented in the field to examine the sensitivity and convergent validity of the MicroMini Motionlogger® Actigraph during strolling and jogging. The following results were revealed: (1) Although the exercise movement speed while jogging was significantly faster than that while strolling, the actigraph readings showed no significant difference between strolling and jogging; (2) The actigraph readings were (significantly or nonsignificantly) negatively correlated with metabolic heat and nonsignificantly correlated with movement speeds. Hence, the actigraph validity for measuring PA intensity while strolling and jogging remains debatable.
Collapse
Affiliation(s)
- Ke-Tsung Han
- Department of Landscape Architecture, National Chin-Yi University of Technology, 57 Sec. 2, Zhongshan Rd., Taichung City 41170, Taiwan.
| | - Po-Ching Wang
- Department of Landscape Architecture, National Chiayi University, 300 Syuefu Rd., Chiayi City 60004, Taiwan.
| |
Collapse
|
30
|
Ndahimana D, Kim EK. Measurement Methods for Physical Activity and Energy Expenditure: a Review. Clin Nutr Res 2017; 6:68-80. [PMID: 28503503 PMCID: PMC5426207 DOI: 10.7762/cnr.2017.6.2.68] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 04/17/2017] [Accepted: 04/19/2017] [Indexed: 12/29/2022] Open
Abstract
Physical activity is defined as any bodily movement produced by skeletal muscles that results in energy expenditure. The benefits of physical activity for health maintenance have been well documented, especially in the prevention and management of chronic diseases. Therefore, accurate measurement of physical activity and energy expenditure is essential both for epidemiological studies and in the clinical context. Given the large number of available methods, it is important to have an understanding of each, especially when one needs to choose a technique to use. The purpose of this review was to discuss the components of total energy expenditure and present advantage and limitations of different methods of physical activity and energy expenditure assessment.
Collapse
Affiliation(s)
- Didace Ndahimana
- Department of Food and Nutrition, Gangneung-Wonju National University, Gangneung 25457, Korea
| | - Eun-Kyung Kim
- Department of Food and Nutrition, Gangneung-Wonju National University, Gangneung 25457, Korea
| |
Collapse
|
31
|
Abstract
Increasing evidence supports a major role for the renin-angiotensin system (RAS) in energy balance physiology. The RAS exists as a circulating system but also as a local paracrine/autocrine signaling mechanism in target tissues including the gastrointestinal tract, the brain, the kidney, and distinct adipose beds. Through activation of various receptors in these target tissues, the RAS contributes to the control of food intake behavior, digestive efficiency, spontaneous physical activity, and aerobic and anaerobic resting metabolism. Although the assortment of methodologies available to assess the various aspects of energy balance can be daunting for an investigator new to this area, a relatively straightforward array of entry-level and advanced methodologies can be employed to comprehensively and quantitatively dissect the effects of experimental manipulations on energy homeostasis. Such methodologies and a simple initial workflow for the use of these methods are described in this chapter, including the use of metabolic caging systems, bomb calorimetry, body composition analyzers, respirometry systems, and direct calorimetry systems. Finally, a brief discussion of the statistical analyses of metabolic data is included.
Collapse
Affiliation(s)
- Justin L Grobe
- Department of Pharmacology, Center for Hypertension Research, The Obesity Research and Education Initiative, François M. Abboud Cardiovascular Research Center, The Fraternal Order of Eagles' Diabetes Research Center, University of Iowa, 51 Newton Rd., 2-307 BSB, Iowa City, IA, 52242, USA.
| |
Collapse
|
32
|
Risperidone-induced weight gain is mediated through shifts in the gut microbiome and suppression of energy expenditure. EBioMedicine 2016; 2:1725-34. [PMID: 26870798 PMCID: PMC4740326 DOI: 10.1016/j.ebiom.2015.10.018] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 10/06/2015] [Accepted: 10/16/2015] [Indexed: 01/05/2023] Open
Abstract
Risperidone is a second-generation antipsychotic that causes weight gain. We hypothesized that risperidone-induced shifts in the gut microbiome are mechanistically involved in its metabolic consequences. Wild-type female C57BL/6J mice treated with risperidone (80 μg/day) exhibited significant excess weight gain, due to reduced energy expenditure, which correlated with an altered gut microbiome. Fecal transplant from risperidone-treated mice caused a 16% reduction in total resting metabolic rate in naïve recipients, attributable to suppression of non-aerobic metabolism. Risperidone inhibited growth of cultured fecal bacteria grown anaerobically more than those grown aerobically. Finally, transplant of the fecal phage fraction from risperidone-treated mice was sufficient to cause excess weight gain in naïve recipients, again through reduced energy expenditure. Collectively, these data highlight a major role for the gut microbiome in weight gain following chronic use of risperidone, and specifically implicates the modulation of non-aerobic resting metabolism in this mechanism.
Collapse
|
33
|
Bardova K, Horakova O, Janovska P, Hansikova J, Kus V, van Schothorst EM, Hoevenaars FP, Uil M, Hensler M, Keijer J, Kopecky J. Early differences in metabolic flexibility between obesity-resistant and obesity-prone mice. Biochimie 2016; 124:163-170. [DOI: 10.1016/j.biochi.2015.11.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/15/2015] [Indexed: 12/25/2022]
|
34
|
Nelson JA. Oxygen consumption rate v. rate of energy utilization of fishes: a comparison and brief history of the two measurements. JOURNAL OF FISH BIOLOGY 2016; 88:10-25. [PMID: 26768970 DOI: 10.1111/jfb.12824] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 09/23/2015] [Indexed: 06/05/2023]
Abstract
Accounting for energy use by fishes has been taking place for over 200 years. The original, and continuing gold standard for measuring energy use in terrestrial animals, is to account for the waste heat produced by all reactions of metabolism, a process referred to as direct calorimetry. Direct calorimetry is not easy or convenient in terrestrial animals and is extremely difficult in aquatic animals. Thus, the original and most subsequent measurements of metabolic activity in fishes have been measured via indirect calorimetry. Indirect calorimetry takes advantage of the fact that oxygen is consumed and carbon dioxide is produced during the catabolic conversion of foodstuffs or energy reserves to useful ATP energy. As measuring [CO2 ] in water is more challenging than measuring [O2 ], most indirect calorimetric studies on fishes have used the rate of O2 consumption. To relate measurements of O2 consumption back to actual energy usage requires knowledge of the substrate being oxidized. Many contemporary studies of O2 consumption by fishes do not attempt to relate this measurement back to actual energy usage. Thus, the rate of oxygen consumption (M˙O2 ) has become a measurement in its own right that is not necessarily synonymous with metabolic rate. Because all extant fishes are obligate aerobes (many fishes engage in substantial net anaerobiosis, but all require oxygen to complete their life cycle), this discrepancy does not appear to be of great concern to the fish biology community, and reports of fish oxygen consumption, without being related to energy, have proliferated. Unfortunately, under some circumstances, these measures can be quite different from one another. A review of the methodological history of the two measurements and a look towards the future are included.
Collapse
Affiliation(s)
- J A Nelson
- Towson University, Department of Biological Sciences, 8000 York Road, Towson, MD 21252, U.S.A
| |
Collapse
|
35
|
Regan MD, Gill I, Richards JG. Calorespirometry reveals that goldfish prioritize aerobic metabolism over metabolic rate depression in all but near-anoxic environments. J Exp Biol 2016; 220:564-572. [DOI: 10.1242/jeb.145169] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 11/21/2016] [Indexed: 10/20/2022]
Abstract
Metabolic rate depression (MRD) has long been proposed as the key metabolic strategy of hypoxic survival, but surprisingly the effects of changes in hypoxic O2 tensions (PwO2) on MRD are largely unexplored. We simultaneously measured the O2 consumption rate (ṀO2) and metabolic heat of goldfish using calorespirometry to test the hypothesis that MRD is employed at hypoxic PwO2s and initiated just below Pcrit, the PwO2 below which ṀO2 is forced to progressively decline as the fish oxyconforms to decreasing PwO2. Specifically, we used closed-chamber and flow-through calorespirometry together with terminal sampling experiments to examine the effects of PwO2 and time on ṀO2, metabolic heat and anaerobic metabolism (lactate and ethanol production). The closed-chamber and flow-through experiments yielded slightly different results. Under closed-chamber conditions with a continually decreasing PwO2, goldfish showed a Pcrit of 3.0±0.3 kPa and metabolic heat production was only depressed at PwO2 between 0 and 0.67 kPa. Under flow-through conditions with PwO2 held at a variety of oxygen tensions for 1 and 4 h, goldfish also initiated MRD between 0 and 0.67 kPa but maintained ṀO2 to 0.67 kPa, indicating that Pcrit is at or below this PwO2. Anaerobic metabolism was strongly activated at PwO2 ≤1.3 kPa, but only used within the first hour at 1.3 and 0.67 kPa as anaerobic end-products did not accumulate between 1 and 4 h exposure. Taken together, it appears that goldfish reserve MRD for near-anoxia, supporting routine metabolic rate at sub-Pcrit PwO2s with the help of anaerobic glycolysis in the closed-chamber experiments, and aerobically after an initial (<1 h) activation of anaerobic metabolism in the flow-through experiments, even at 0.67 kPa PwO2.
Collapse
Affiliation(s)
- Matthew D. Regan
- Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada
| | - Ivan Gill
- Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada
| | - Jeffrey G. Richards
- Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada
| |
Collapse
|
36
|
Measuring Methane Production from Ruminants. Trends Biotechnol 2015; 34:26-35. [PMID: 26603286 DOI: 10.1016/j.tibtech.2015.10.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 10/14/2015] [Accepted: 10/21/2015] [Indexed: 11/22/2022]
Abstract
Radiative forcing of methane (CH4) is significantly higher than carbon dioxide (CO2) and its enteric production by ruminant livestock is one of the major sources of greenhouse gas emissions. CH4 is also an important marker of farming productivity, because it is associated with the conversion of feed to product in livestock. Consequently, measurement of enteric CH4 is emerging as an important research topic. In this review, we briefly describe the conversion of carbohydrate to CH4 by the bacterial community within gut, and highlight some of the key host-microbiome interactions. We then provide a picture of current progress in techniques for measuring enteric CH4, the context in which these technologies are used, and the challenges faced. We also discuss solutions to existing problems and new approaches currently in development.
Collapse
|
37
|
Littlejohn NK, Grobe JL. Opposing tissue-specific roles of angiotensin in the pathogenesis of obesity, and implications for obesity-related hypertension. Am J Physiol Regul Integr Comp Physiol 2015; 309:R1463-73. [PMID: 26491099 DOI: 10.1152/ajpregu.00224.2015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 10/15/2015] [Indexed: 12/24/2022]
Abstract
Metabolic disease, specifically obesity, has now become the greatest challenge to improving cardiovascular health. The renin-angiotensin system (RAS) exists as both a circulating hormone system and as a local paracrine signaling mechanism within various tissues including the brain, kidney, and adipose, and this system is strongly implicated in cardiovascular health and disease. Growing evidence also implicates the RAS in the control of energy balance, supporting the concept that the RAS may be mechanistically involved in the pathogenesis of obesity and obesity hypertension. Here, we review the involvement of the RAS in the entire spectrum of whole organism energy balance mechanisms, including behaviors (food ingestion and spontaneous physical activity) and biological processes (digestive efficiency and both aerobic and nonaerobic resting metabolic rates). We hypothesize that opposing, tissue-specific effects of the RAS to modulate these various components of energy balance can explain the apparently paradoxical results reported by energy-balance studies that involve stimulating, versus disrupting, the RAS. We propose a model in which such opposing and tissue-specific effects of the RAS can explain the failure of simple, global RAS blockade to result in weight loss in humans, and hypothesize that obesity-mediated uncoupling of endogenous metabolic rate control mechanisms can explain the phenomenon of obesity-related hypertension.
Collapse
Affiliation(s)
- Nicole K Littlejohn
- Department of Pharmacology, the Obesity Research and Education Initiative, the Fraternal Order of Eagles' Diabetes Research Center, the François M. Abboud Cardiovascular Research Center, and the Center for Hypertension Research, University of Iowa, Iowa City, Iowa
| | - Justin L Grobe
- Department of Pharmacology, the Obesity Research and Education Initiative, the Fraternal Order of Eagles' Diabetes Research Center, the François M. Abboud Cardiovascular Research Center, and the Center for Hypertension Research, University of Iowa, Iowa City, Iowa
| |
Collapse
|
38
|
Meyer CW, Reitmeir P, Tschöp MH. Exploration of Energy Metabolism in the Mouse Using Indirect Calorimetry: Measurement of Daily Energy Expenditure (DEE) and Basal Metabolic Rate (BMR). ACTA ACUST UNITED AC 2015; 5:205-222. [PMID: 26331756 DOI: 10.1002/9780470942390.mo140216] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Current comprehensive mouse metabolic phenotyping involves studying energy balance in cohorts of mice via indirect calorimetry, which determines heat release from changes in respiratory air composition. Here, we describe the measurement of daily energy expenditure (DEE) and basal metabolic rate (BMR) in mice. These well-defined metabolic descriptors serve as meaningful first-line read-outs for metabolic phenotyping and should be reported when exploring energy expenditure in mice. For further guidance, the issue of appropriate sample sizes and the frequency of sampling of metabolic measurements is also discussed.
Collapse
Affiliation(s)
- Carola W Meyer
- Institute for Diabetes and Obesity, Helmholtz-Zentrum München GmbH, Neuherberg, Germany
| | - Peter Reitmeir
- Institute for Health Economics and Health Care Management, Helmholtz-Zentrum München GmbH, Neuherberg, Germany
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity, Helmholtz-Zentrum München GmbH, Neuherberg, Germany.,Division of Metabolic Diseases, Department of Medicine, Technische Universität München, Munich, Germany
| |
Collapse
|
39
|
Weidemann BJ, Voong S, Morales-Santiago FI, Kahn MZ, Ni J, Littlejohn NK, Claflin KE, Burnett CML, Pearson NA, Lutter ML, Grobe JL. Dietary Sodium Suppresses Digestive Efficiency via the Renin-Angiotensin System. Sci Rep 2015; 5:11123. [PMID: 26068176 PMCID: PMC4464075 DOI: 10.1038/srep11123] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 05/18/2015] [Indexed: 12/22/2022] Open
Abstract
Dietary fats and sodium are both palatable and are hypothesized to synergistically contribute to ingestive behavior and thereby obesity. Contrary to this hypothesis, C57BL/6J mice fed a 45% high fat diet exhibited weight gain that was inhibited by increased dietary sodium content. This suppressive effect of dietary sodium upon weight gain was mediated specifically through a reduction in digestive efficiency, with no effects on food intake behavior, physical activity, or resting metabolism. Replacement of circulating angiotensin II levels reversed the effects of high dietary sodium to suppress digestive efficiency. While the AT1 receptor antagonist losartan had no effect in mice fed low sodium, the AT2 receptor antagonist PD-123,319 suppressed digestive efficiency. Correspondingly, genetic deletion of the AT2 receptor in FVB/NCrl mice resulted in suppressed digestive efficiency even on a standard chow diet. Together these data underscore the importance of digestive efficiency in the pathogenesis of obesity, and implicate dietary sodium, the renin-angiotensin system, and the AT2 receptor in the control of digestive efficiency regardless of mouse strain or macronutrient composition of the diet. These findings highlight the need for greater understanding of nutrient absorption control physiology, and prompt more uniform assessment of digestive efficiency in animal studies of energy balance.
Collapse
Affiliation(s)
| | - Susan Voong
- Departments of Pharmacology, University of Iowa, Iowa City, IA
| | | | - Michael Z Kahn
- Departments of Psychiatry, University of Iowa, Iowa City, IA
| | - Jonathan Ni
- Departments of Pharmacology, University of Iowa, Iowa City, IA
| | | | | | | | | | - Michael L Lutter
- 1] Departments of Psychiatry, University of Iowa, Iowa City, IA. [2] The Fraternal Order of Eagles' Diabetes Research Center, University of Iowa, Iowa City, IA. [3] The Obesity Research and Education Initiative, University of Iowa, Iowa City, IA
| | - Justin L Grobe
- 1] Departments of Pharmacology, University of Iowa, Iowa City, IA. [2] The Fraternal Order of Eagles' Diabetes Research Center, University of Iowa, Iowa City, IA. [3] The Obesity Research and Education Initiative, University of Iowa, Iowa City, IA. [4] The Center for Hypertension Research, University of Iowa, Iowa City, IA
| |
Collapse
|
40
|
Ramsay DS, Al-Noori S, Shao J, Leroux BG, Woods SC, Kaiyala KJ. Predicting addictive vulnerability: individual differences in initial responding to a drug's pharmacological effects. PLoS One 2015; 10:e0124740. [PMID: 25880426 PMCID: PMC4400068 DOI: 10.1371/journal.pone.0124740] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 03/04/2015] [Indexed: 12/31/2022] Open
Abstract
Considerable data suggest that individuals who appear minimally disrupted during an initial drug administration have elevated risk for abusing the drug later. A better understanding of this association could lead to more effective strategies for preventing and treating drug addiction. To investigate this phenomenon using a rigorous experimental model, we first administered the abused inhalant nitrous oxide (N2O) to rats in a total calorimetry and temperature system to identify groups that were sensitive or insensitive to the drug’s hypothermic effect. We then enrolled the two groups in a novel N2O self-administration paradigm. The initially insensitive rats self-administered significantly more N2O than sensitive rats, an important step in the transition to addiction. Continuous non-invasive measurement of core temperature and its underlying determinants during screening revealed that both groups had similarly increased heat loss during initial N2O administration, but that insensitive rats generated more heat and thereby remained relatively normothermic. Calorimetry testing conducted after self-administration revealed that whereas N2O’s effect on heat loss persisted comparably for both groups, initially insensitive rats actually over-responded by generating excess heat and becoming hyperthermic. Thus, rats with the greatest initial heat-producing compensatory response(s) appeared initially insensitive to N2O-induced hypothermia, subsequently self-administered more N2O, and developed hyperthermic overcompensation during N2O inhalation, consistent with increased abuse potential and an allostatic model of addictive vulnerability.
Collapse
Affiliation(s)
- Douglas S. Ramsay
- Department of Oral Health Sciences, University of Washington, Seattle, WA, United States of America
- * E-mail:
| | - Salwa Al-Noori
- Department of Oral Health Sciences, University of Washington, Seattle, WA, United States of America
| | - Jason Shao
- Department of Biostatistics, University of Washington, Seattle, WA, United States of America
| | - Brian G. Leroux
- Department of Oral Health Sciences, University of Washington, Seattle, WA, United States of America
- Department of Biostatistics, University of Washington, Seattle, WA, United States of America
| | - Stephen C. Woods
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, United States of America
| | - Karl J. Kaiyala
- Department of Oral Health Sciences, University of Washington, Seattle, WA, United States of America
| |
Collapse
|
41
|
White CR, Kearney MR. Metabolic scaling in animals: methods, empirical results, and theoretical explanations. Compr Physiol 2014; 4:231-56. [PMID: 24692144 DOI: 10.1002/cphy.c110049] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Life on earth spans a size range of around 21 orders of magnitude across species and can span a range of more than 6 orders of magnitude within species of animal. The effect of size on physiology is, therefore, enormous and is typically expressed by how physiological phenomena scale with mass(b). When b ≠ 1 a trait does not vary in direct proportion to mass and is said to scale allometrically. The study of allometric scaling goes back to at least the time of Galileo Galilei, and published scaling relationships are now available for hundreds of traits. Here, the methods of scaling analysis are reviewed, using examples for a range of traits with an emphasis on those related to metabolism in animals. Where necessary, new relationships have been generated from published data using modern phylogenetically informed techniques. During recent decades one of the most controversial scaling relationships has been that between metabolic rate and body mass and a number of explanations have been proposed for the scaling of this trait. Examples of these mechanistic explanations for metabolic scaling are reviewed, and suggestions made for comparing between them. Finally, the conceptual links between metabolic scaling and ecological patterns are examined, emphasizing the distinction between (1) the hypothesis that size- and temperature-dependent variation among species and individuals in metabolic rate influences ecological processes at levels of organization from individuals to the biosphere and (2) mechanistic explanations for metabolic rate that may explain the size- and temperature-dependence of this trait.
Collapse
Affiliation(s)
- Craig R White
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | | |
Collapse
|
42
|
Rozman J, Klingenspor M, Hrabě de Angelis M. A review of standardized metabolic phenotyping of animal models. Mamm Genome 2014; 25:497-507. [DOI: 10.1007/s00335-014-9532-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/03/2014] [Indexed: 12/17/2022]
|
43
|
Wernecke K, Lamprecht I, Jöhren O, Lehnert H, Schulz C. Nesfatin-1 increases energy expenditure and reduces food intake in rats. Obesity (Silver Spring) 2014; 22:1662-8. [PMID: 24596169 DOI: 10.1002/oby.20736] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/31/2014] [Accepted: 03/02/2014] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Energy homeostasis results from a balance of food intake and energy expenditure, accomplished by the interaction of peripheral and central nervous signals. The recently discovered adipokine nesfatin-1 is involved in the central control of food intake, but whether it also participates in the regulation of thermogenesis is unknown. METHODS Nesfatin-1 was administered intracerebroventricularly to freely moving, male Wistar rats and direct calorimetry was performed to assess its effects on thermogenesis. Furthermore, food intake was measured and hypothalamic and N. tractus solitarius (NTS) neuropeptide expression was determined by quantitative real-time polymerace chain reaction. Leptin, which is involved in both the regulation of food intake and thermogenesis, was used as positive control. RESULTS For the first time it was shown that central nervous administration of nesfatin-1 profoundly increases thermogenesis in rats to a similar extent as leptin and the role of both peptides in the control of food intake was confirmed. Nesfatin-1 significantly downregulated neuropeptide Y (NPY) mRNA expression in both hypothalamus and NTS. CONCLUSIONS The results strongly support the prominent role of nesfatin-1 for both energy expenditure and food intake and NPY neurons appear to be involved in this effect.
Collapse
Affiliation(s)
- Kerstin Wernecke
- Department of Internal Medicine I, University of Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany
| | | | | | | | | |
Collapse
|
44
|
|
45
|
Burnett CML, Grobe JL. Dietary effects on resting metabolic rate in C57BL/6 mice are differentially detected by indirect (O2/CO2 respirometry) and direct calorimetry. Mol Metab 2014; 3:460-4. [PMID: 24944905 PMCID: PMC4060218 DOI: 10.1016/j.molmet.2014.03.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 03/10/2014] [Indexed: 12/21/2022] Open
Abstract
Resting metabolic rate (RMR) studies frequently involve genetically-manipulated mice and high fat diets (HFD). We hypothesize that the use of inadequate methods impedes the identification of novel regulators of RMR. This idea was tested by simultaneously measuring RMR by direct calorimetry and respirometry in C57BL/6J mice fed chow, 45% HFD, and then returned to chow. Comparing results during chow feeding uncovered an underestimation of RMR by respirometry (0.010 ± 0.001 kcal/h, P < 0.05), which is equivalent in magnitude to ∼2% of total daily caloric turnover. RMR during 45% HFD feeding was increased by respirometry (+0.013 ± 0.003 kcal/h, P < 0.05), but not direct calorimetry (+0.001 ± 0.002 kcal/h). Both methods indicated that return to chow reduced RMR compared to HFD, though direct calorimetry indicated a reduction below the initial chow fed state (−0.019 ± 0.004 kcal/h versus baseline, P < 0.05) that was not detected by respirometry (−0.003 ± 0.002 kcal/h versus baseline). These results highlight method-specific interpretations of the effects of dietary interventions upon RMR in mice, and prompt the reevaluation of preclinical screening methods used to identify novel RMR modulators.
Collapse
Affiliation(s)
- Colin M L Burnett
- Department of Pharmacology, The Obesity Research and Education Initiative, The Fraternal Order of Eagles' Diabetes Research Center, The François M. Abboud Cardiovascular Research Center, and The Center on Functional Genomics of Hypertension, University of Iowa, IA, USA
| | - Justin L Grobe
- Department of Pharmacology, The Obesity Research and Education Initiative, The Fraternal Order of Eagles' Diabetes Research Center, The François M. Abboud Cardiovascular Research Center, and The Center on Functional Genomics of Hypertension, University of Iowa, IA, USA
| |
Collapse
|
46
|
Burger M, van Breukelen F. Construction of a low cost and highly sensitive direct heat calorimeter suitable for estimating metabolic rate in small animals. J Therm Biol 2013. [DOI: 10.1016/j.jtherbio.2013.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
47
|
Even PC. Body size, spontaneous activity and thermogenesis effects on energy expenditure: an introduction to a topic on energy metabolism. Front Physiol 2013; 4:301. [PMID: 24146654 PMCID: PMC3797956 DOI: 10.3389/fphys.2013.00301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 10/01/2013] [Indexed: 12/11/2022] Open
Affiliation(s)
- Patrick C Even
- UMR914 Nutrition Physiology and Ingestive Behavior, AgroParisTech INRA, Paris, France
| |
Collapse
|
48
|
Burnett CML, Grobe JL. Direct calorimetry identifies deficiencies in respirometry for the determination of resting metabolic rate in C57Bl/6 and FVB mice. Am J Physiol Endocrinol Metab 2013; 305:E916-24. [PMID: 23964071 PMCID: PMC3798702 DOI: 10.1152/ajpendo.00387.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Substantial research efforts have been aimed at identifying novel targets to increase resting metabolic rate (RMR) as an adjunct approach to the treatment of obesity. Respirometry (one form of "indirect calorimetry") is unquestionably the dominant technique used in the obesity research field to assess RMR in vivo, although this method relies upon a lengthy list of assumptions that are likely to be violated in pharmacologically or genetically manipulated animals. A "total" calorimeter, including a gradient layer direct calorimeter coupled to a conventional respirometer, was used to test the accuracy of respirometric-based estimations of RMR in laboratory mice (Mus musculus Linnaeus) of the C57Bl/6 and FVB background strains. Using this combined calorimeter, we determined that respirometry underestimates RMR of untreated 9- to 12-wk-old male mice by ∼10-12%. Quantitative and qualitative differences resulted between methods for untreated C57Bl/6 and FVB mice, C57Bl/6 mice treated with ketamine-xylazine anesthesia, and FVB mice with genetic deletion of the angiotensin II type 2 receptor. We conclude that respirometric methods underestimate RMR in mice in a magnitude that is similar to or greater than the desired RMR effects of novel therapeutics. Sole reliance upon respirometry to assess RMR in mice may lead to false quantitative and qualitative conclusions regarding the effects of novel interventions. Increased use of direct calorimetry for the assessment of RMR and confirmation of respirometry results and the reexamination of previously discarded potential obesity therapeutics are warranted.
Collapse
Affiliation(s)
- Colin M L Burnett
- Department of Pharmacology, Center on Functional Genomics of Hypertension, Fraternal Order of Eagles Diabetes Research Center, and The Obesity Research and Education Initiative, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | | |
Collapse
|
49
|
Speakman JR. Measuring energy metabolism in the mouse - theoretical, practical, and analytical considerations. Front Physiol 2013; 4:34. [PMID: 23504620 PMCID: PMC3596737 DOI: 10.3389/fphys.2013.00034] [Citation(s) in RCA: 180] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/12/2013] [Indexed: 12/14/2022] Open
Abstract
The mouse is one of the most important model organisms for understanding human genetic function and disease. This includes characterization of the factors that influence energy expenditure and dysregulation of energy balance leading to obesity and its sequelae. Measuring energy metabolism in the mouse presents a challenge because the animals are small, and in this respect it presents similar challenges to measuring energy demands in many other species of small mammal. This paper considers some theoretical, practical, and analytical considerations to be considered when measuring energy expenditure in mice. Theoretically total daily energy expenditure is comprised of several different components: basal or resting expenditure, physical activity, thermoregulation, and the thermic effect of food. Energy expenditure in mice is normally measured using open flow indirect calorimetry apparatus. Two types of system are available – one of which involves a single small Spartan chamber linked to a single analyzer, which is ideal for measuring the individual components of energy demand. The other type of system involves a large chamber which mimics the home cage environment and is generally configured with several chambers/analyzer. These latter systems are ideal for measuring total daily energy expenditure but at present do not allow accurate decomposition of the total expenditure into its components. The greatest analytical challenge for mouse expenditure data is how to account for body size differences between individuals. This has been a matter of some discussion for at least 120 years. The statistically most appropriate approach is to use analysis of covariance with individual aspects of body composition as independent predictors.
Collapse
Affiliation(s)
- John R Speakman
- Key State Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences Beijing, China ; Institute of Biological and Environmental Sciences, University of Aberdeen Aberdeen, Scotland, UK
| |
Collapse
|
50
|
Regan MD, Gosline JM, Richards JG. A simple and affordable calorespirometer for assessing metabolic rates of fishes. J Exp Biol 2013; 216:4507-13. [DOI: 10.1242/jeb.093500] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Summary
Calorimetry is the measurement of the heat liberated during energy transformations in chemical reactions. When applied to living organisms, it measures the heat released due to the energy transformations associated with metabolism under both aerobic and anaerobic conditions. This is in contrast to the often-used respirometric techniques for assessing energy turnover, which can only be used under fully aerobic conditions. Accordingly, calorimetry is considered the 'gold standard' for quantifying metabolic rate, yet despite this, it remains a seldom-used technique among comparative physiologists. The reasons for this are related to the expense and perceived difficulty of the technique. We have designed and constructed an inexpensive flow-through calorespirometer capable of detecting rates of metabolic heat loss and oxygen consumption (ṀO2) in fishes under a variety of environmental conditions over long-term experiments. The metabolic heat of the fish is detected as a (micro)voltage by a collection of Peltier units wired in series, while oxygen optodes placed on the inflowing and outflowing water lines are used for the calculation of ṀO2. The apparatus is constructed in a differential fashion to account for ambient temperature fluctuations. This paper describes the design and construction of the calorespirometer for ~$1,300 CDN. Using the goldfish (Carassius auratus auratus), we show that the calorespirometer is sensitive to changes in metabolic rate brought about by pharmacological manipulation and severe hypoxia exposures.
Collapse
|