1
|
Petersen KF, Dufour S, Mehal WZ, Shulman GI. Glucagon promotes increased hepatic mitochondrial oxidation and pyruvate carboxylase flux in humans with fatty liver disease. Cell Metab 2024:S1550-4131(24)00325-5. [PMID: 39197461 DOI: 10.1016/j.cmet.2024.07.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/23/2024] [Accepted: 07/31/2024] [Indexed: 09/01/2024]
Abstract
We assessed in vivo rates of hepatic mitochondrial oxidation, gluconeogenesis, and β-hydroxybutyrate (β-OHB) turnover by positional isotopomer NMR tracer analysis (PINTA) in individuals with metabolic-dysfunction-associated steatotic liver (MASL) (fatty liver) and MASL disease (MASLD) (steatohepatitis) compared with BMI-matched control participants with no hepatic steatosis. Hepatic fat content was quantified by localized 1H magnetic resonance spectroscopy (MRS). We found that in vivo rates of hepatic mitochondrial oxidation were unaltered in the MASL and MASLD groups compared with the control group. A physiological increase in plasma glucagon concentrations increased in vivo rates of hepatic mitochondrial oxidation by 50%-75% in individuals with and without MASL and increased rates of glucose production by ∼50% in the MASL group, which could be attributed in part to an ∼30% increase in rates of mitochondrial pyruvate carboxylase flux. These results demonstrate that (1) rates of hepatic mitochondrial oxidation are not substantially altered in individuals with MASL and MASLD and (2) glucagon increases rates of hepatic mitochondrial oxidation.
Collapse
Affiliation(s)
- Kitt Falk Petersen
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA.
| | - Sylvie Dufour
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Wajahat Z Mehal
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA; West Haven Medical Center, West Haven, CT, USA
| | - Gerald I Shulman
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| |
Collapse
|
2
|
Akingbesote ND, Leitner BP, Jovin DG, Desrouleaux R, Owusu D, Zhu W, Li Z, Pollak MN, Perry RJ. Gene and protein expression and metabolic flux analysis reveals metabolic scaling in liver ex vivo and in vivo. eLife 2023; 12:e78335. [PMID: 37219930 PMCID: PMC10205083 DOI: 10.7554/elife.78335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 05/08/2023] [Indexed: 05/24/2023] Open
Abstract
Metabolic scaling, the inverse correlation of metabolic rates to body mass, has been appreciated for more than 80 years. Studies of metabolic scaling have largely been restricted to mathematical modeling of caloric intake and oxygen consumption, and mostly rely on computational modeling. The possibility that other metabolic processes scale with body size has not been comprehensively studied. To address this gap in knowledge, we employed a systems approach including transcriptomics, proteomics, and measurement of in vitro and in vivo metabolic fluxes. Gene expression in livers of five species spanning a 30,000-fold range in mass revealed differential expression according to body mass of genes related to cytosolic and mitochondrial metabolic processes, and to detoxication of oxidative damage. To determine whether flux through key metabolic pathways is ordered inversely to body size, we applied stable isotope tracer methodology to study multiple cellular compartments, tissues, and species. Comparing C57BL/6 J mice with Sprague-Dawley rats, we demonstrate that while ordering of metabolic fluxes is not observed in in vitro cell-autonomous settings, it is present in liver slices and in vivo. Together, these data reveal that metabolic scaling extends beyond oxygen consumption to other aspects of metabolism, and is regulated at the level of gene and protein expression, enzyme activity, and substrate supply.
Collapse
Affiliation(s)
- Ngozi D Akingbesote
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| | - Brooks P Leitner
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| | - Daniel G Jovin
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| | - Reina Desrouleaux
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Comparative Medicine, Yale UniversityNew HavenUnited States
| | - Dennis Owusu
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| | - Wanling Zhu
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| | - Zongyu Li
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| | - Michael N Pollak
- Lady Davis Institute for Medical Research, Jewish General HospitalMontrealCanada
- Department of Oncology, McGill UniversityMontrealCanada
| | - Rachel J Perry
- Department of Cellular & Molecular Physiology, Yale UniversityNew HavenUnited States
- Department of Internal Medicine – Endocrinology, Yale UniversityNew HavenUnited States
| |
Collapse
|
3
|
Lee G, Lee SM, Kim HU. A contribution of metabolic engineering to addressing medical problems: Metabolic flux analysis. Metab Eng 2023; 77:283-293. [PMID: 37075858 DOI: 10.1016/j.ymben.2023.04.008] [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: 02/04/2023] [Revised: 03/20/2023] [Accepted: 04/12/2023] [Indexed: 04/21/2023]
Abstract
Metabolic engineering has served as a systematic discipline for industrial biotechnology as it has offered systematic tools and methods for strain development and bioprocess optimization. Because these metabolic engineering tools and methods are concerned with the biological network of a cell with emphasis on metabolic network, they have also been applied to a range of medical problems where better understanding of metabolism has also been perceived to be important. Metabolic flux analysis (MFA) is a unique systematic approach initially developed in the metabolic engineering community, and has proved its usefulness and potential when addressing a range of medical problems. In this regard, this review discusses the contribution of MFA to addressing medical problems. For this, we i) provide overview of the milestones of MFA, ii) define two main branches of MFA, namely constraint-based reconstruction and analysis (COBRA) and isotope-based MFA (iMFA), and iii) present successful examples of their medical applications, including characterizing the metabolism of diseased cells and pathogens, and identifying effective drug targets. Finally, synergistic interactions between metabolic engineering and biomedical sciences are discussed with respect to MFA.
Collapse
Affiliation(s)
- GaRyoung Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Sang Mi Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Hyun Uk Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea; BioProcess Engineering Research Center and BioInformatics Research Center, KAIST, Daejeon, 34141, Republic of Korea.
| |
Collapse
|
4
|
Malloy CR, Sherry AD, Alger JR, Jin ES. Recent progress in analysis of intermediary metabolism by ex vivo 13 C NMR. NMR IN BIOMEDICINE 2023; 36:e4817. [PMID: 35997012 DOI: 10.1002/nbm.4817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/03/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
Advanced imaging technologies, large-scale metabolomics, and the measurement of gene transcripts or enzyme expression all enable investigations of intermediary metabolism in human patients. Complementary information about fluxes in individual metabolic pathways may be obtained by ex vivo 13 C NMR of blood or tissue biopsies. Simple molecules such as 13 C-labeled glucose are readily administered to patients prior to surgical biopsies, and 13 C-labeled glycerol is easily administered orally to outpatients. Here, we review recent progress in practical applications of 13 C NMR to study cancer biology, the response to oxidative stress, gluconeogenesis, triglyceride synthesis in patients, as well as new insights into compartmentation of metabolism in the cytosol. The technical aspects of obtaining the sample, preparing material for analysis, and acquiring the spectra are relatively simple. This approach enables convenient, valuable, and quantitative insights into intermediary metabolism in patients.
Collapse
Affiliation(s)
- Craig R Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Veterans Affairs North Texas Healthcare System, Dallas, Texas, USA
| | - A Dean Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Chemistry, University of Texas at Dallas, Richardson, Texas, USA
| | - Jeffry R Alger
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Neurology, Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | - Eunsook S Jin
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| |
Collapse
|
5
|
Bartman CR, Weilandt DR, Shen Y, Lee WD, Han Y, TeSlaa T, Jankowski CSR, Samarah L, Park NR, da Silva-Diz V, Aleksandrova M, Gultekin Y, Marishta A, Wang L, Yang L, Roichman A, Bhatt V, Lan T, Hu Z, Xing X, Lu W, Davidson S, Wühr M, Vander Heiden MG, Herranz D, Guo JY, Kang Y, Rabinowitz JD. Slow TCA flux and ATP production in primary solid tumours but not metastases. Nature 2023; 614:349-357. [PMID: 36725930 PMCID: PMC10288502 DOI: 10.1038/s41586-022-05661-6] [Citation(s) in RCA: 107] [Impact Index Per Article: 107.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/14/2022] [Indexed: 02/03/2023]
Abstract
Tissues derive ATP from two pathways-glycolysis and the tricarboxylic acid (TCA) cycle coupled to the electron transport chain. Most energy in mammals is produced via TCA metabolism1. In tumours, however, the absolute rates of these pathways remain unclear. Here we optimize tracer infusion approaches to measure the rates of glycolysis and the TCA cycle in healthy mouse tissues, Kras-mutant solid tumours, metastases and leukaemia. Then, given the rates of these two pathways, we calculate total ATP synthesis rates. We find that TCA cycle flux is suppressed in all five primary solid tumour models examined and is increased in lung metastases of breast cancer relative to primary orthotopic tumours. As expected, glycolysis flux is increased in tumours compared with healthy tissues (the Warburg effect2,3), but this increase is insufficient to compensate for low TCA flux in terms of ATP production. Thus, instead of being hypermetabolic, as commonly assumed, solid tumours generally produce ATP at a slower than normal rate. In mouse pancreatic cancer, this is accommodated by the downregulation of protein synthesis, one of this tissue's major energy costs. We propose that, as solid tumours develop, cancer cells shed energetically expensive tissue-specific functions, enabling uncontrolled growth despite a limited ability to produce ATP.
Collapse
Affiliation(s)
- Caroline R Bartman
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Daniel R Weilandt
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Yihui Shen
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Won Dong Lee
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Yujiao Han
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Tara TeSlaa
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
- Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, CA, USA
| | - Connor S R Jankowski
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Laith Samarah
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Noel R Park
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | | | - Maya Aleksandrova
- Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, USA
| | - Yetis Gultekin
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Boston, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Boston, MA, USA
| | - Argit Marishta
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Lin Wang
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lifeng Yang
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
- Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Shanghai, China
| | - Asael Roichman
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Vrushank Bhatt
- Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, USA
| | - Taijin Lan
- Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, USA
| | - Zhixian Hu
- Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, USA
| | - Xi Xing
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Wenyun Lu
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
| | - Shawn Davidson
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Martin Wühr
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Matthew G Vander Heiden
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Boston, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Boston, MA, USA
| | - Daniel Herranz
- Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, USA
| | | | - Yibin Kang
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Joshua D Rabinowitz
- Department of Chemistry, Princeton University, Princeton, NJ, USA.
- Lewis-Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA.
- Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA.
| |
Collapse
|
6
|
Hubbard BT, LaMoia TE, Goedeke L, Gaspar RC, Galsgaard KD, Kahn M, Mason GF, Shulman GI. Q-Flux: A method to assess hepatic mitochondrial succinate dehydrogenase, methylmalonyl-CoA mutase, and glutaminase fluxes in vivo. Cell Metab 2023; 35:212-226.e4. [PMID: 36516861 PMCID: PMC9887731 DOI: 10.1016/j.cmet.2022.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 09/14/2022] [Accepted: 11/21/2022] [Indexed: 12/15/2022]
Abstract
The mammalian succinate dehydrogenase (SDH) complex has recently been shown as capable of operating bidirectionally. Here, we develop a method (Q-Flux) capable of measuring absolute rates of both forward (VSDH(F)) and reverse (VSDH(R)) flux through SDH in vivo while also deconvoluting the amount of glucose derived from four discreet carbon sources in the liver. In validation studies, a mitochondrial uncoupler increased net SDH flux by >100% in awake rodents but also increased SDH cycling. During hyperglucagonemia, attenuated pyruvate cycling enhances phosphoenolpyruvate carboxykinase efficiency to drive increased gluconeogenesis, which is complemented by increased glutaminase (GLS) flux, methylmalonyl-CoA mutase (MUT) flux, and glycerol conversion to glucose. During hyperinsulinemic-euglycemic clamp, both pyruvate carboxylase and GLS are suppressed, while VSDH(R) is increased. Unstimulated MUT is a minor anaplerotic reaction but is readily induced by small amounts of propionate, which elicits glucagon-like metabolic rewiring. Taken together, Q-Flux yields a comprehensive picture of hepatic mitochondrial metabolism and should be broadly useful to researchers.
Collapse
Affiliation(s)
- Brandon T Hubbard
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Traci E LaMoia
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Leigh Goedeke
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Rafael C Gaspar
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Katrine D Galsgaard
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Mario Kahn
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Graeme F Mason
- Department of Radiology & Biomedical Imaging, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Psychiatry & Biomedical Engineering, Yale School of Medicine, New Haven, CT 06510, USA
| | - Gerald I Shulman
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA.
| |
Collapse
|
7
|
Andrew R, Stimson RH. Mapping endocrine networks by stable isotope tracing. CURRENT OPINION IN ENDOCRINE AND METABOLIC RESEARCH 2022; 26:100381. [PMID: 39185272 PMCID: PMC11344083 DOI: 10.1016/j.coemr.2022.100381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Hormones regulate metabolic homeostasis through interlinked dynamic networks of proteins and small molecular weight metabolites, and state-of-the-art chemical technologies have been developed to decipher these complex pathways. Stable-isotope tracers have largely replaced radiotracers to measure flux in humans, building on advances in nuclear magnetic resonance spectroscopy and mass spectrometry. These technologies are now being applied to localise molecules within tissues. Radiotracers are still highly valuable both preclinically and in 3D imaging by positron emission tomography. The coming of age of vibrational spectroscopy in conjunction with stable-isotope tracing offers detailed cellular insights to map complex biological processes. Together with computational modelling, these approaches are poised to coalesce into multi-modal platforms to provide hitherto inaccessible dynamic and spatial insights into endocrine signalling.
Collapse
Affiliation(s)
- Ruth Andrew
- University/ British Heart Foundation Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, 47, Little France Crescent, Edinburgh, EH16 4TJ, United Kingdom
| | - Roland H Stimson
- University/ British Heart Foundation Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, 47, Little France Crescent, Edinburgh, EH16 4TJ, United Kingdom
| |
Collapse
|
8
|
Hughey CC, Puchalska P, Crawford PA. Integrating the contributions of mitochondrial oxidative metabolism to lipotoxicity and inflammation in NAFLD pathogenesis. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159209. [DOI: 10.1016/j.bbalip.2022.159209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 06/25/2022] [Accepted: 07/27/2022] [Indexed: 11/28/2022]
|
9
|
DeBerardinis RJ, Keshari KR. Metabolic analysis as a driver for discovery, diagnosis, and therapy. Cell 2022; 185:2678-2689. [PMID: 35839759 PMCID: PMC9469798 DOI: 10.1016/j.cell.2022.06.029] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 12/14/2022]
Abstract
Metabolic anomalies contribute to tissue dysfunction. Current metabolism research spans from organelles to populations, and new technologies can accommodate investigation across these scales. Here, we review recent advancements in metabolic analysis, including small-scale metabolomics techniques amenable to organelles and rare cell types, functional screening to explore how cells respond to metabolic stress, and imaging approaches to non-invasively assess metabolic perturbations in diseases. We discuss how metabolomics provides an informative phenotypic dimension that complements genomic analysis in Mendelian and non-Mendelian disorders. We also outline pressing challenges and how addressing them may further clarify the biochemical basis of human disease.
Collapse
Affiliation(s)
- Ralph J DeBerardinis
- Howard Hughes Medical Institute and Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Kayvan R Keshari
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| |
Collapse
|
10
|
Georgiev A, Granata C, Roden M. The role of mitochondria in the pathophysiology and treatment of common metabolic diseases in humans. Am J Physiol Cell Physiol 2022; 322:C1248-C1259. [PMID: 35508191 DOI: 10.1152/ajpcell.00035.2022] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Common metabolic diseases such as obesity, type 2 diabetes mellitus and non-alcoholic fatty liver disease significantly contribute to morbidity and mortality worldwide. They frequently associate with insulin resistance and altered mitochondrial functionality. Insulin-responsive tissues can show changes in mitochondrial features such as oxidative capacity, mitochondrial content and turnover, which do not necessarily reflect abnormalities but rather adaption to a certain metabolic condition. Lifestyle modifications and classic or novel drugs can modify these alterations and help treating these metabolic diseases. This review addresses the role of mitochondria in human metabolic diseases and discusses potential future research directions.
Collapse
Affiliation(s)
- Asen Georgiev
- Institute for Clinical Diabetology, German, Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany
| | - Cesare Granata
- Institute for Clinical Diabetology, German, Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany.,Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia.,Institute for Health and Sport (iHeS), Victoria University, Melbourne, VIC, Australia
| | - Michael Roden
- Institute for Clinical Diabetology, German, Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany.,Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Düsseldorf, Düsseldorf, Germany
| |
Collapse
|
11
|
Can E, Bastiaansen JAM, Couturier DL, Gruetter R, Yoshihara HAI, Comment A. [ 13C]bicarbonate labelled from hyperpolarized [1- 13C]pyruvate is an in vivo marker of hepatic gluconeogenesis in fasted state. Commun Biol 2022; 5:10. [PMID: 35013537 PMCID: PMC8748681 DOI: 10.1038/s42003-021-02978-2] [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: 07/31/2021] [Accepted: 12/07/2021] [Indexed: 01/07/2023] Open
Abstract
Hyperpolarized [1-13C]pyruvate enables direct in vivo assessment of real-time liver enzymatic activities by 13C magnetic resonance. However, the technique usually requires the injection of a highly supraphysiological dose of pyruvate. We herein demonstrate that liver metabolism can be measured in vivo with hyperpolarized [1-13C]pyruvate administered at two- to three-fold the basal plasma concentration. The flux through pyruvate dehydrogenase, assessed by 13C-labeling of bicarbonate in the fed condition, was found to be saturated or partially inhibited by supraphysiological doses of hyperpolarized [1-13C]pyruvate. The [13C]bicarbonate signal detected in the liver of fasted rats nearly vanished after treatment with a phosphoenolpyruvate carboxykinase (PEPCK) inhibitor, indicating that the signal originates from the flux through PEPCK. In addition, the normalized [13C]bicarbonate signal in fasted untreated animals is dose independent across a 10-fold range, highlighting that PEPCK and pyruvate carboxylase are not saturated and that hepatic gluconeogenesis can be directly probed in vivo with hyperpolarized [1-13C]pyruvate. Can et al. demonstrate the ability to use hyperpolarized [1-13C]pyruvate at nearphysiological concentrations to directly assess liver enzymatic activities by 13C magnetic resonance. While in the fed state, the normalized [13C]bicarbonate signal produced from hyperpolarized [1-13C]pyruvate derives from PDH activity, which is saturated at supraphysiological doses, it results from PEPCK in the fasted state and is dose-independent, allowing non-invasive in vivo detection of hepatic gluconeogenesis.”
Collapse
Affiliation(s)
- Emine Can
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
| | - Jessica A M Bastiaansen
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland.,Department of Diagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | | | - Rolf Gruetter
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
| | - Hikari A I Yoshihara
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
| | - Arnaud Comment
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, Cambridgeshire, CB2 0RE, UK. .,General Electric Healthcare, Chalfont St Giles, Buckinghamshire, HP8 4SP, UK.
| |
Collapse
|
12
|
Rahim M, Ragavan M, Deja S, Merritt ME, Burgess SC, Young JD. INCA 2.0: A tool for integrated, dynamic modeling of NMR- and MS-based isotopomer measurements and rigorous metabolic flux analysis. Metab Eng 2022; 69:275-285. [PMID: 34965470 PMCID: PMC8789327 DOI: 10.1016/j.ymben.2021.12.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/17/2021] [Accepted: 12/22/2021] [Indexed: 01/03/2023]
Abstract
Metabolic flux analysis (MFA) combines experimental measurements and computational modeling to determine biochemical reaction rates in live biological systems. Advancements in analytical instrumentation, such as nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS), have facilitated chemical separation and quantification of isotopically enriched metabolites. However, no software packages have been previously described that can integrate isotopomer measurements from both MS and NMR analytical platforms and have the flexibility to estimate metabolic fluxes from either isotopic steady-state or dynamic labeling experiments. By applying physiologically relevant cardiac and hepatic metabolic models to assess NMR isotopomer measurements, we herein test and validate new modeling capabilities of our enhanced flux analysis software tool, INCA 2.0. We demonstrate that INCA 2.0 can simulate and regress steady-state 13C NMR datasets from perfused hearts with an accuracy comparable to other established flux assessment tools. Furthermore, by simulating the infusion of three different 13C acetate tracers, we show that MFA based on dynamic 13C NMR measurements can more precisely resolve cardiac fluxes compared to isotopically steady-state flux analysis. Finally, we show that estimation of hepatic fluxes using combined 13C NMR and MS datasets improves the precision of estimated fluxes by up to 50%. Overall, our results illustrate how the recently added NMR data modeling capabilities of INCA 2.0 can enable entirely new experimental designs that lead to improved flux resolution and can be applied to a wide range of biological systems and measurement time courses.
Collapse
Affiliation(s)
- Mohsin Rahim
- Department of Chemical and Biomolecular, Nashville, TN, 37212, USA
| | - Mukundan Ragavan
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Stanislaw Deja
- Center for Human Nutrition, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Matthew E Merritt
- Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Shawn C Burgess
- Center for Human Nutrition, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jamey D Young
- Department of Chemical and Biomolecular, Nashville, TN, 37212, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, School of Engineering, Nashville, TN, 37212, USA.
| |
Collapse
|
13
|
Non-Invasive Analysis of Human Liver Metabolism by Magnetic Resonance Spectroscopy. Metabolites 2021; 11:metabo11110751. [PMID: 34822409 PMCID: PMC8623827 DOI: 10.3390/metabo11110751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
The liver is a key node of whole-body nutrient and fuel metabolism and is also the principal site for detoxification of xenobiotic compounds. As such, hepatic metabolite concentrations and/or turnover rates inform on the status of both hepatic and systemic metabolic diseases as well as the disposition of medications. As a tool to better understand liver metabolism in these settings, in vivo magnetic resonance spectroscopy (MRS) offers a non-invasive means of monitoring hepatic metabolic activity in real time both by direct observation of concentrations and dynamics of specific metabolites as well as by observation of their enrichment by stable isotope tracers. This review summarizes the applications and advances in human liver metabolic studies by in vivo MRS over the past 35 years and discusses future directions and opportunities that will be opened by the development of ultra-high field MR systems and by hyperpolarized stable isotope tracers.
Collapse
|
14
|
Tsilingiris D, Tzeravini E, Koliaki C, Dalamaga M, Kokkinos A. The Role of Mitochondrial Adaptation and Metabolic Flexibility in the Pathophysiology of Obesity and Insulin Resistance: an Updated Overview. Curr Obes Rep 2021; 10:191-213. [PMID: 33840072 DOI: 10.1007/s13679-021-00434-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/30/2021] [Indexed: 12/27/2022]
Abstract
PURPOSE OF REVIEW The term "metabolic flexibility" denotes the dynamic responses of the cellular oxidative machinery in order to adapt to changes in energy substrate availability. A progressive loss of this adaptive capacity has been implicated in the development of obesity-related comorbidities. Mitochondria are dynamic intracellular organelles which play a fundamental role in energy metabolism, and the mitochondrial adaptation to environmental challenges may be viewed as the functional component of metabolic flexibility. Herein, we attempt to comprehensively review the available evidence regarding the role of mitochondrial adaptation and metabolic flexibility in the pathogenesis of obesity and related morbidities, namely insulin resistance states and non-alcoholic fatty liver disease (NAFLD). RECENT FINDINGS Overall, there is a concrete body of evidence to support the presence of impaired mitochondrial adaptation as a principal component of systemic metabolic inflexibility in conditions related to obesity. There are still many unresolved questions regarding the relationship between the gradual loss of mitochondrial adaptability and the progression of obesity-related complications, such as causality issues, the timely appearance and reversibility of the described disturbances, and the generalizability of the findings to the mitochondrial content of every affected tissue or organ. The evidence regarding the causality between the observed associations remains inconclusive, although most of the available data points towards a bidirectional, potentially mutually amplifying relationship. The spectrum of NAFLD is of particular interest, since functional and pathological changes in the course of its development closely mirror the progression of dysmetabolism, if not constituting a dynamic component of the latter.
Collapse
Affiliation(s)
- Dimitrios Tsilingiris
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece.
- Department of Internal Medicine I and Clinical Chemistry, University of Heidelberg, Heidelberg, Germany.
| | - Evangelia Tzeravini
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Chrysi Koliaki
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Maria Dalamaga
- Department of Biological Chemistry, School of Medicine, National and Kapodistrian University of Athens, Mikras Asias 75, 11527, Athens, Greece
| | - Alexander Kokkinos
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
15
|
Abstract
The reactions of the tricarboxylic acid (TCA) cycle allow the controlled combustion of fat and carbohydrate. In principle, TCA cycle intermediates are regenerated on every turn and can facilitate the oxidation of an infinite number of nutrient molecules. However, TCA cycle intermediates can be lost to cataplerotic pathways that provide precursors for biosynthesis, and they must be replaced by anaplerotic pathways that regenerate these intermediates. Together, anaplerosis and cataplerosis help regulate rates of biosynthesis by dictating precursor supply, and they play underappreciated roles in catabolism and cellular energy status. They facilitate recycling pathways and nitrogen trafficking necessary for catabolism, and they influence redox state and oxidative capacity by altering TCA cycle intermediate concentrations. These functions vary widely by tissue and play emerging roles in disease. This article reviews the roles of anaplerosis and cataplerosis in various tissues and discusses how they alter carbon transitions, and highlights their contribution to mechanisms of disease. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Melissa Inigo
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA;
| | - Stanisław Deja
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA; .,Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Shawn C Burgess
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA; .,Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| |
Collapse
|
16
|
Abstract
Altered metabolic activity contributes to the pathogenesis of a number of diseases, including diabetes, heart failure, cancer, fibrosis and neurodegeneration. These diseases, and organismal metabolism more generally, are only partially recapitulated by cell culture models. Accordingly, it is important to measure metabolism in vivo. Over the past century, researchers studying glucose homeostasis have developed strategies for the measurement of tissue-specific and whole-body metabolic activity (pathway fluxes). The power of these strategies has been augmented by recent advances in metabolomics technologies. Here, we review techniques for measuring metabolic fluxes in intact mammals and discuss how to analyse and interpret the results. In tandem, we describe important findings from these techniques, and suggest promising avenues for their future application. Given the broad importance of metabolism to health and disease, more widespread application of these methods holds the potential to accelerate biomedical progress.
Collapse
Affiliation(s)
- Caroline R Bartman
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Tara TeSlaa
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Joshua D Rabinowitz
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
- Department of Chemistry, Princeton University, Princeton, NJ, USA.
| |
Collapse
|
17
|
Abstract
PURPOSE OF REVIEW Nonalcoholic fatty liver disease (NAFLD) is defined as the abnormal accumulation of lipids in the liver, called hepatic steatosis, which occurs most often as a concomitant of the metabolic syndrome. Its incidence has surged significantly in recent decades concomitant with the obesity pandemic and increasing consumption of refined carbohydrates and saturated fats. This makes a review of the origins of NAFLD timely and relevant. RECENT FINDINGS This disorder, which shares histologic markers found in alcoholic fatty liver disease, was named NAFLD to distinguish it from the latter. Recently, however, the term metabolic-associated fatty liver disease (MAFLD) has been suggested as a refinement of NAFLD that should highlight the central, etiologic role of insulin resistance, obesity, and diabetes mellitus. The complexity of the pathways involved in the regulation of hepatic triglyceride synthesis and utilization have become obvious over the past 10 years, including the recent identification of monogenic causes of metabolic-associated fatty liver disease. These include PNPLA3, transmembrane 6 superfamily member 2, GCKR, membrane-bound O-acyltransferase 7 suggest targets for new therapies for hepatic steatosis. SUMMARY The current review can serve as a guide to the complex pathways involved in the maintenance of hepatic triglyceride levels as well as an introduction to the most recent discoveries, including those of key genes that have provided opportunities for new and novel therapeutics.
Collapse
Affiliation(s)
- Leinys S Santos-Baez
- Division of Preventive Medicine and Nutrition, Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | | |
Collapse
|
18
|
Hasenour CM, Rahim M, Young JD. In Vivo Estimates of Liver Metabolic Flux Assessed by 13C-Propionate and 13C-Lactate Are Impacted by Tracer Recycling and Equilibrium Assumptions. Cell Rep 2021; 32:107986. [PMID: 32755580 PMCID: PMC7451222 DOI: 10.1016/j.celrep.2020.107986] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 06/01/2020] [Accepted: 07/13/2020] [Indexed: 01/08/2023] Open
Abstract
Isotope-based assessment of metabolic flux is achieved through a judicious balance of measurements and assumptions. Recent publications debate the validity of key assumptions used to model stable isotope labeling of liver metabolism in vivo. Here, we examine the controversy surrounding estimates of liver citric acid cycle and gluconeogenesis fluxes using a flexible modeling platform that enables rigorous testing of standard assumptions. Fasted C57BL/6J mice are infused with [13C3]lactate or [13C3]propionate isotopes, and hepatic fluxes are regressed using models with gradually increasing complexity and relaxed assumptions. We confirm that liver pyruvate cycling fluxes are incongruent between different 13C tracers in models with conventional assumptions. When models are expanded to include more labeling measurements and fewer constraining assumptions, however, liver pyruvate cycling is significant, and inconsistencies in hepatic flux estimates using [13C3]lactate and [13C3]propionate isotopes emanate, in part, from peripheral tracer recycling and incomplete isotope equilibration within the citric acid cycle.
Collapse
Affiliation(s)
- Clinton M Hasenour
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235, USA
| | - Mohsin Rahim
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235, USA
| | - Jamey D Young
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37235, USA.
| |
Collapse
|
19
|
Svyatova A, Kozinenko VP, Chukanov NV, Burueva DB, Chekmenev EY, Chen YW, Hwang DW, Kovtunov KV, Koptyug IV. PHIP hyperpolarized [1- 13C]pyruvate and [1- 13C]acetate esters via PH-INEPT polarization transfer monitored by 13C NMR and MRI. Sci Rep 2021; 11:5646. [PMID: 33707497 PMCID: PMC7952547 DOI: 10.1038/s41598-021-85136-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 02/18/2021] [Indexed: 01/31/2023] Open
Abstract
Parahydrogen-induced polarization of 13C nuclei by side-arm hydrogenation (PHIP-SAH) for [1-13C]acetate and [1-13C]pyruvate esters with application of PH-INEPT-type pulse sequences for 1H to 13C polarization transfer is reported, and its efficiency is compared with that of polarization transfer based on magnetic field cycling (MFC). The pulse-sequence transfer approach may have its merits in some applications because the entire hyperpolarization procedure is implemented directly in an NMR or MRI instrument, whereas MFC requires a controlled field variation at low magnetic fields. Optimization of the PH-INEPT-type transfer sequences resulted in 13C polarization values of 0.66 ± 0.04% and 0.19 ± 0.02% for allyl [1-13C]pyruvate and ethyl [1-13C]acetate, respectively, which is lower than the corresponding polarization levels obtained with MFC for 1H to 13C polarization transfer (3.95 ± 0.05% and 0.65 ± 0.05% for allyl [1-13C]pyruvate and ethyl [1-13C]acetate, respectively). Nevertheless, a significant 13C NMR signal enhancement with respect to thermal polarization allowed us to perform 13C MR imaging of both biologically relevant hyperpolarized molecules which can be used to produce useful contrast agents for the in vivo imaging applications.
Collapse
Affiliation(s)
- Alexandra Svyatova
- grid.419389.e0000 0001 2163 7228International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, Russia 630090 ,grid.4605.70000000121896553Novosibirsk State University, 2 Pirogova St., Novosibirsk, Russia 630090 ,grid.418953.2Institute of Cytology and Genetics SB RAS, 10 Ac. Lavrentieva Ave., Novosibirsk, Russia 630090
| | - Vitaly P. Kozinenko
- grid.419389.e0000 0001 2163 7228International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, Russia 630090 ,grid.4605.70000000121896553Novosibirsk State University, 2 Pirogova St., Novosibirsk, Russia 630090
| | - Nikita V. Chukanov
- grid.419389.e0000 0001 2163 7228International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, Russia 630090 ,grid.4605.70000000121896553Novosibirsk State University, 2 Pirogova St., Novosibirsk, Russia 630090
| | - Dudari B. Burueva
- grid.419389.e0000 0001 2163 7228International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, Russia 630090 ,grid.4605.70000000121896553Novosibirsk State University, 2 Pirogova St., Novosibirsk, Russia 630090
| | - Eduard Y. Chekmenev
- grid.254444.70000 0001 1456 7807Department of Chemistry, Wayne State University, Detroit, MI 48201 USA ,grid.254444.70000 0001 1456 7807Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201 USA ,grid.254444.70000 0001 1456 7807Integrative Biosciences, Wayne State University, Detroit, MI 48201 USA ,grid.4886.20000 0001 2192 9124Russian Academy of Sciences, Moscow, Russia 119991
| | - Yu-Wen Chen
- grid.28665.3f0000 0001 2287 1366Institute of Biomedical Sciences, Academia Sinica, Taipei, 115 Taiwan (Republic of China)
| | - Dennis W. Hwang
- grid.28665.3f0000 0001 2287 1366Institute of Biomedical Sciences, Academia Sinica, Taipei, 115 Taiwan (Republic of China)
| | - Kirill V. Kovtunov
- grid.419389.e0000 0001 2163 7228International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, Russia 630090 ,grid.4605.70000000121896553Novosibirsk State University, 2 Pirogova St., Novosibirsk, Russia 630090
| | - Igor V. Koptyug
- grid.419389.e0000 0001 2163 7228International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk, Russia 630090
| |
Collapse
|
20
|
Metabolic Imaging in Non-Alcoholic Fatty Liver Disease: Applications of Magnetic Resonance Spectroscopy. J Clin Med 2021; 10:jcm10040632. [PMID: 33562284 PMCID: PMC7915174 DOI: 10.3390/jcm10040632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 12/20/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is poised to dominate the landscape of clinical hepatology in the 21st century. Its complex, interdependent aetiologies, non-linear disease progression and uncertain natural history have presented great challenges to the development of effective therapies. Progress will require an integrated approach to uncover molecular mediators, key pathogenic milestones and response to intervention at the metabolic level. The advent of precision imaging has yielded unprecedented insights into these processes. Quantitative imaging biomarkers such as magnetic resonance imaging (MRI), spectroscopy (MRS) and elastography (MRE) present robust, powerful tools with which to probe NAFLD metabolism and fibrogenesis non-invasively, in real time. Specific advantages of MRS include the ability to quantify static metabolite concentrations as well as dynamic substrate flux in vivo. Thus, a vast range of key metabolic events in the natural history of NAFLD can be explored using MRS. Here, we provide an overview of MRS for the clinician, as well as key pathways exploitable by MRS in vivo. Development, optimisation and validation of multinuclear MRS, in combination with other quantitative imaging techniques, may ultimately provide a robust, non-invasive alternative to liver biopsy for observational and longitudinal studies. Through enabling deeper insight into inflammatory and fibrogenic cascades, MRS may facilitate identification of novel therapeutic targets and clinically meaningful endpoints in NAFLD. Its widespread use in future could conceivably accelerate study design, data acquisition and availability of disease-modifying therapies at a population level.
Collapse
|
21
|
Anstey CM, Russell FD. Measurement of the Concentration of Citrate in Human Biofluids in Patients Undergoing Continuous Renal Replacement Therapy Using Regional Citrate Anticoagulation: Application of a Two-Step Enzymatic Assay. Blood Purif 2021; 50:848-856. [PMID: 33550280 DOI: 10.1159/000513150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 11/17/2020] [Indexed: 11/19/2022]
Abstract
BACKGROUND Continuous renal replacement therapy (CRRT) with regional citrate anticoagulation (RCA) is now commonly used to treat acute kidney injury in critically ill patients. The concentration of citrate is not routinely measured, with citrate accumulation and/or toxicity primarily assessed using surrogate measures. OBJECTIVES The aim of this study was to measure the concentration of citrate in plasma and ultrafiltrate in patients receiving CRRT with RCA using a modified commercial enzymatic assay. METHODS After meeting inclusion criteria, blood was sampled from 20 patients before, during, and after episodes of filtration. Using spectrophotometry, samples were tested for citrate concentration. Demographic and other clinical and biochemical data were also collected. Throughout, a 15 mmol/L solution of trisodium citrate was used as the prefilter anticoagulant. Results were analysed using STATA (v15.0) and presented as mean (SD), median (IQR), or simple proportion. Comparisons were made using either the Student t test or the Wilcoxon rank-sum test. Correlation was assessed using Pearson's r. RESULTS Twenty patients (17 males) were enrolled in the study. Mean (SD) age was 63.7 years (9.9). Median (IQR) ICU length of stay was 281 h (199, 422) with 85% undergoing intermittent positive pressure ventilation. Median APACHE 3 score was 95 (87, 117) with an overall 30% mortality rate. Median filtration time was 85 h (46, 149). No difference was found between pre- and post-filtration plasma citrate concentrations (79 µmol/L [50] vs. 71 µmol/L [42], p = 0.65). Mean citrate concentration during filtration was 508 µmol/L (221) with a maximum of 1,070 µmol/L. This was significantly higher than the pre/post levels (p < 0.001). CONCLUSIONS Plasma concentrations of citrate rose significantly during episodes of CRRT using RCA returning back to normal after cessation of treatment.
Collapse
Affiliation(s)
- Chris M Anstey
- School of Medicine, Sunshine Coast Campus, Griffith University, Birtinya, Queensland, Australia,
| | - Fraser D Russell
- Genecology Research Centre, School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Queensland, Australia
| |
Collapse
|
22
|
Therapeutic potential of mitochondrial uncouplers for the treatment of metabolic associated fatty liver disease and NASH. Mol Metab 2021; 46:101178. [PMID: 33545391 PMCID: PMC8085597 DOI: 10.1016/j.molmet.2021.101178] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 01/18/2021] [Accepted: 01/28/2021] [Indexed: 12/13/2022] Open
Abstract
Background Mitochondrial uncouplers shuttle protons across the inner mitochondrial membrane via a pathway that is independent of adenosine triphosphate (ATP) synthase, thereby uncoupling nutrient oxidation from ATP production and dissipating the proton gradient as heat. While initial toxicity concerns hindered their therapeutic development in the early 1930s, there has been increased interest in exploring the therapeutic potential of mitochondrial uncouplers for the treatment of metabolic diseases. Scope of review In this review, we cover recent advances in the mechanisms by which mitochondrial uncouplers regulate biological processes and disease, with a particular focus on metabolic associated fatty liver disease (MAFLD), nonalcoholic hepatosteatosis (NASH), insulin resistance, and type 2 diabetes (T2D). We also discuss the challenges that remain to be addressed before synthetic and natural mitochondrial uncouplers can successfully enter the clinic. Major conclusions Rodent and non-human primate studies suggest that a myriad of small molecule mitochondrial uncouplers can safely reverse MAFLD/NASH with a wide therapeutic index. Despite this, further characterization of the tissue- and cell-specific effects of mitochondrial uncouplers is needed. We propose targeting the dosing of mitochondrial uncouplers to specific tissues such as the liver and/or developing molecules with self-limiting properties to induce a subtle and sustained increase in mitochondrial inefficiency, thereby avoiding systemic toxicity concerns.
Collapse
|
23
|
Song JD, Alves TC, Befroy DE, Perry RJ, Mason GF, Zhang XM, Munk A, Zhang Y, Zhang D, Cline GW, Rothman DL, Petersen KF, Shulman GI. Dissociation of Muscle Insulin Resistance from Alterations in Mitochondrial Substrate Preference. Cell Metab 2020; 32:726-735.e5. [PMID: 33035493 PMCID: PMC8218871 DOI: 10.1016/j.cmet.2020.09.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/14/2020] [Accepted: 09/09/2020] [Indexed: 12/28/2022]
Abstract
Alterations in muscle mitochondrial substrate preference have been postulated to play a major role in the pathogenesis of muscle insulin resistance. In order to examine this hypothesis, we assessed the ratio of mitochondrial pyruvate oxidation (VPDH) to rates of mitochondrial citrate synthase flux (VCS) in muscle. Contrary to this hypothesis, we found that high-fat-diet (HFD)-fed insulin-resistant rats did not manifest altered muscle substrate preference (VPDH/VCS) in soleus or quadriceps muscles in the fasting state. Furthermore, hyperinsulinemic-euglycemic (HE) clamps increased VPDH/VCS in both muscles in normal and insulin-resistant rats. We then examined the muscle VPDH/VCS flux in insulin-sensitive and insulin-resistant humans and found similar relative rates of VPDH/VCS, following an overnight fast (∼20%), and similar increases in VPDH/VCS fluxes during a HE clamp. Altogether, these findings demonstrate that alterations in mitochondrial substrate preference are not an essential step in the pathogenesis of muscle insulin resistance.
Collapse
Affiliation(s)
- Joongyu D Song
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Tiago C Alves
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Douglas E Befroy
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Radiology & Bioengineering, Yale School of Medicine, New Haven, CT, USA; PeakAnalysts, Benenden, Kent, UK
| | - Rachel J Perry
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA
| | - Graeme F Mason
- Department of Radiology & Bioengineering, Yale School of Medicine, New Haven, CT, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Xian-Man Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Alexander Munk
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Ye Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Dongyan Zhang
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Gary W Cline
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Douglas L Rothman
- Department of Radiology & Bioengineering, Yale School of Medicine, New Haven, CT, USA
| | - Kitt Falk Petersen
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark.
| | - Gerald I Shulman
- Department of Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA.
| |
Collapse
|
24
|
Goedeke L, Peng L, Montalvo-Romeral V, Butrico GM, Dufour S, Zhang XM, Perry RJ, Cline GW, Kievit P, Chng K, Petersen KF, Shulman GI. Controlled-release mitochondrial protonophore (CRMP) reverses dyslipidemia and hepatic steatosis in dysmetabolic nonhuman primates. Sci Transl Med 2020; 11:11/512/eaay0284. [PMID: 31578240 DOI: 10.1126/scitranslmed.aay0284] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/13/2019] [Indexed: 12/21/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is estimated to affect up to one-third of the general population, and new therapies are urgently required. Our laboratory previously developed a controlled-release mitochondrial protonophore (CRMP) that is functionally liver-targeted and promotes oxidation of hepatic triglycerides. Although we previously demonstrated that CRMP safely reverses hypertriglyceridemia, fatty liver, hepatic inflammation, and fibrosis in diet-induced rodent models of obesity, there remains a critical need to assess its safety and efficacy in a model highly relevant to humans. Here, we evaluated the impact of longer-term CRMP treatment on hepatic mitochondrial oxidation and on the reversal of hypertriglyceridemia, NAFLD, and insulin resistance in high-fat, fructose-fed cynomolgus macaques (n = 6) and spontaneously obese dysmetabolic rhesus macaques (n = 12). Using positional isotopomer nuclear magnetic resonance tracer analysis (PINTA), we demonstrated that acute CRMP treatment (single dose, 5 mg/kg) increased rates of hepatic mitochondrial fat oxidation by 40%. Six weeks of CRMP treatment reduced hepatic triglycerides in both nonhuman primate models independently of changes in body weight, food intake, body temperature, or adverse reactions. CRMP treatment was also associated with a 20 to 30% reduction in fasting plasma triglycerides and low-density lipoprotein (LDL)-cholesterol in dysmetabolic nonhuman primates. Oral administration of CRMP reduced endogenous glucose production by 18%, attributable to a 20% reduction in hepatic acetyl-coenzyme A (CoA) content [as assessed by whole-body β-hydroxybutyrate (β-OHB) turnover] and pyruvate carboxylase flux. Collectively, these studies provide proof-of-concept data to support the development of liver-targeted mitochondrial uncouplers for the treatment of metabolic syndrome in humans.
Collapse
Affiliation(s)
- Leigh Goedeke
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Liang Peng
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Gina M Butrico
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Sylvie Dufour
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Xian-Man Zhang
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Rachel J Perry
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA.,Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| | - Gary W Cline
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Paul Kievit
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Keefe Chng
- Crown Bioscience Louisiana Inc., New Iberia, LA 70560, USA
| | - Kitt Falk Petersen
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA
| | - Gerald I Shulman
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA. .,Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT 06510, USA
| |
Collapse
|
25
|
Chen Z, Tian R, She Z, Cai J, Li H. Role of oxidative stress in the pathogenesis of nonalcoholic fatty liver disease. Free Radic Biol Med 2020; 152:116-141. [PMID: 32156524 DOI: 10.1016/j.freeradbiomed.2020.02.025] [Citation(s) in RCA: 589] [Impact Index Per Article: 147.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/20/2020] [Accepted: 02/26/2020] [Indexed: 02/07/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) has emerged as the most common chronic liver disease worldwide and is strongly associated with the presence of oxidative stress. Disturbances in lipid metabolism lead to hepatic lipid accumulation, which affects different reactive oxygen species (ROS) generators, including mitochondria, endoplasmic reticulum, and NADPH oxidase. Mitochondrial function adapts to NAFLD mainly through the downregulation of the electron transport chain (ETC) and the preserved or enhanced capacity of mitochondrial fatty acid oxidation, which stimulates ROS overproduction within different ETC components upstream of cytochrome c oxidase. However, non-ETC sources of ROS, in particular, fatty acid β-oxidation, appear to produce more ROS in hepatic metabolic diseases. Endoplasmic reticulum stress and NADPH oxidase alterations are also associated with NAFLD, but the degree of their contribution to oxidative stress in NAFLD remains unclear. Increased ROS generation induces changes in insulin sensitivity and in the expression and activity of key enzymes involved in lipid metabolism. Moreover, the interaction between redox signaling and innate immune signaling forms a complex network that regulates inflammatory responses. Based on the mechanistic view described above, this review summarizes the mechanisms that may account for the excessive production of ROS, the potential mechanistic roles of ROS that drive NAFLD progression, and therapeutic interventions that are related to oxidative stress.
Collapse
Affiliation(s)
- Ze Chen
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Institute of Model Animals of Wuhan University, Wuhan, 430072, PR China
| | - Ruifeng Tian
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Institute of Model Animals of Wuhan University, Wuhan, 430072, PR China
| | - Zhigang She
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Institute of Model Animals of Wuhan University, Wuhan, 430072, PR China; Basic Medical School, Wuhan University, Wuhan, 430071, PR China; Medical Research Institute, School of Medicine, Wuhan University, Wuhan, 430071, PR China
| | - Jingjing Cai
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Department of Cardiology, The Third Xiangya Hospital, Central South University, Changsha, 410013, PR China; Institute of Model Animals of Wuhan University, Wuhan, 430072, PR China
| | - Hongliang Li
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, 430060, PR China; Institute of Model Animals of Wuhan University, Wuhan, 430072, PR China; Basic Medical School, Wuhan University, Wuhan, 430071, PR China; Medical Research Institute, School of Medicine, Wuhan University, Wuhan, 430071, PR China.
| |
Collapse
|
26
|
Stender S, Zaha VG, Malloy CR, Sudderth J, DeBerardinis RJ, Park JM. Assessment of Rapid Hepatic Glycogen Synthesis in Humans Using Dynamic 13C Magnetic Resonance Spectroscopy. Hepatol Commun 2020; 4:425-433. [PMID: 32140658 PMCID: PMC7049683 DOI: 10.1002/hep4.1458] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 11/19/2019] [Indexed: 01/04/2023] Open
Abstract
Carbon-13 magnetic resonance spectroscopy (MRS) following oral intake of 13C-labeled glucose is the gold standard for imaging glycogen metabolism in humans. However, the temporal resolution of previous studies has been >13 minutes. Here, we describe a high-sensitivity 13C MRS method for imaging hepatic glycogen synthesis with a temporal resolution of 1 minute or less. Nuclear magnetic resonance spectra were acquired from the liver of 3 healthy volunteers, using a 13C clamshell radiofrequency transmit and paddle-shaped array receive coils in a 3 Tesla magnetic resonance imaging system. Following a 15-minute baseline 13C MRS scan of the liver, [1-13C]-glucose was ingested and 13C MRS data were acquired for an additional 1-3 hours. Dynamic change of the hepatic glycogen synthesis level was analyzed by reconstructing the acquired MRS data with temporal resolutions of 30 seconds to 15 minutes. Plasma levels of 13C-labeled glucose and lactate were measured using gas chromatography-mass spectrometry. While not detected at baseline 13C MRS, [1-13C]-labeled α-glucose and β-glucose and glycogen peaks accumulated rapidly, beginning as early as ~2 minutes after oral administration of [1-13C]-glucose. The [1-13C]-glucose signals peaked at ~5 minutes, whereas [1-13C]-glycogen peaked at ~25 minutes after [1-13C]-glucose ingestion; both signals declined toward baseline levels over the next 1-3 hours. Plasma levels of 13C-glucose and 13C-lactate rose gradually, and approximately 20% of all plasma glucose and 5% of plasma lactate were 13C-labeled by 2 hours after ingestion. Conclusion: We observed rapid accumulation of hepatic [1-13C]-glycogen following orally administered [1-13C]-glucose, using a dynamic 13C MRS method with a temporal resolution of 1 minute or less. Commercially available technology allows high temporal resolution studies of glycogen metabolism in the human liver.
Collapse
Affiliation(s)
- Stefan Stender
- Department of Molecular Genetics University of Texas Southwestern Medical Center Dallas TX.,Department of Clinical Biochemistry Rigshospitalet Copenhagen Denmark
| | - Vlad G Zaha
- Advanced Imaging Research Center University of Texas Southwestern Medical Center Dallas TX.,Department of Internal Medicine University of Texas Southwestern Medical Center Dallas TX
| | - Craig R Malloy
- Advanced Imaging Research Center University of Texas Southwestern Medical Center Dallas TX.,Department of Internal Medicine University of Texas Southwestern Medical Center Dallas TX
| | - Jessica Sudderth
- Howard Hughes Medical Institute and Children's Medical Center Research Institute University of Texas Southwestern Medical Center Dallas TX
| | - Ralph J DeBerardinis
- Howard Hughes Medical Institute and Children's Medical Center Research Institute University of Texas Southwestern Medical Center Dallas TX
| | - Jae Mo Park
- Advanced Imaging Research Center University of Texas Southwestern Medical Center Dallas TX.,Department of Radiology University of Texas Southwestern Medical Center Dallas TX.,Department of Electrical and Computer Engineering University of Texas at Dallas Richardson TX
| |
Collapse
|
27
|
Abstract
"Omics"-based analyses are widely used in numerous areas of research, advances in instrumentation (both hardware and software) allow investigators to collect a wealth of data and therein characterize metabolic systems. Although analyses generally examine differences in absolute or relative (fold-) changes in concentrations, the ability to extract mechanistic insight would benefit from the use of isotopic tracers. Herein, we discuss important concepts that should be considered when stable isotope tracers are used to capture biochemical flux. Special attention is placed on in vivo systems, however, many of the general ideas have immediate impact on studies in cellular models or isolated-perfused tissues. While it is somewhat trivial to administer labeled precursor molecules and measure the enrichment of downstream products, the ability to make correct interpretations can be challenging. We will outline several critical factors that may influence choices when developing and/or applying a stable isotope tracer method. For example, is there a "best" tracer for a given study? How do I administer a tracer? When do I collect my sample(s)? While these questions may seem straightforward, we will present scenarios that can have dramatic effects on conclusions surrounding apparent rates of metabolic activity.
Collapse
Affiliation(s)
- Stephen F Previs
- Department of Chemistry, Merck & Co., Inc., Kenilworth, NJ, USA.
| | - Daniel P Downes
- Department of Chemistry, Merck & Co., Inc., Kenilworth, NJ, USA
| |
Collapse
|
28
|
Carreau AM, Jin ES, Garcia-Reyes Y, Rahat H, Nadeau KJ, Malloy CR, Cree-Green M. A simple method to monitor hepatic gluconeogenesis and triglyceride synthesis following oral sugar tolerance test in obese adolescents. Am J Physiol Regul Integr Comp Physiol 2019; 317:R134-R142. [PMID: 31042400 DOI: 10.1152/ajpregu.00047.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Hepatic energy metabolism is a key element in many metabolic diseases. Hepatic anaplerosis provides carbons for gluconeogenesis (GNG) and triglyceride (TG) synthesis. We aimed to optimize a protocol that measures hepatic anaplerotic contribution for GNG, TG synthesis, and hepatic pentose phosphate pathway (PPP) activity using a single dose of oral [U-13C3]glycerol paired with an oral sugar tolerance test (OSTT) in a population with significant insulin resistance. The OSTT (75 g glucose + 25 g fructose) was administered to eight obese adolescents with polycystic ovarian syndrome (PCOS) followed by ingestion of [U-13C3]glycerol at t = 180 or t = 210 min. 13C-labeling patterns of serum glucose and TG-glycerol were determined by nuclear magnetic resonance. 13C enrichment in plasma TG-glycerol was detectable and stable from 240 to 390 min with the [U-13C3]glycerol drink at t = 180 min(3.65 ± 2.3 to 4.47 ± 1.4%; P > 0.4), but the enrichment was undetectable at 240 min with the glycerol drink at t = 210 min. The relative contribution from anaplerosis was determined at the end of the OSTT [18.5 ±3.4% (t = 180 min) vs. 16.0 ± 3.5% (t = 210 min); P = 0.27]. [U-13C3]glycerol was incorporated into GNG 390 min after the OSTT with an enrichment of 7.5-12.5%. Glucose derived from TCA cycle activity was 0.3-1%, and the PPP activity was 2.8-4.7%. In conclusion, it is possible to obtain relative measurements of hepatic anaplerotic contribution to both GNG and TG esterification following an OSTT in a highly insulin-resistant population using a minimally invasive technique. Tracer administration should be timed to allow enough de novo TG esterification and endogenous glucose release after the sugar drink.
Collapse
Affiliation(s)
- Anne-Marie Carreau
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Eunsook S Jin
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Yesenia Garcia-Reyes
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Haseeb Rahat
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Kristen J Nadeau
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Colorado Anschutz Medical Campus , Aurora, Colorado.,Center for Women's Health Research , Aurora, Colorado
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Melanie Cree-Green
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Colorado Anschutz Medical Campus , Aurora, Colorado.,Center for Women's Health Research , Aurora, Colorado
| |
Collapse
|
29
|
Alger JR, Sherry AD, Malloy CR. tcaSIM: A Simulation Program for Optimal Design of 13C Tracer Experiments for Analysis of Metabolic Flux by NMR and Mass Spectroscopy. ACTA ACUST UNITED AC 2019; 6:176-187. [PMID: 31745452 DOI: 10.2174/2213235x07666181219115856] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Increasingly sophisticated instrumentation for chemical separations and identification has facilitated rapid advancements in our understanding of the metabolome. Since many analyses are performed using either mass spectroscopy (MS) or nuclear magnetic resonance (NMR) spectroscopy, the spin ½ stable 13C isotope is now widely used as a metabolic tracer. There is strong interest in quantitative analysis of metabolic flux through pathways in vivo, particularly in human patients. Although instrumentation advances and scientific interests in metabolism are increasing in parallel, a practical and rational design of a 13C tracer study can be challenging. Prior to planning the details of a tracer experiment, is it important to consider whether the analytical results will be sensitive to flux through the pathways of interest. Here, we briefly summarize the various approaches that have been used to design carbon tracer experiments, outline the sources of complexity, and illustrate the use of a software tool, tcaSIM, to aid in the experimental design of both MS and NMR data in complex systems including patients.
Collapse
Affiliation(s)
- Jeffry R Alger
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas.,NeuroSpectroScopics LLC, Sherman Oaks, California
| | - A Dean Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas.,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas.,Department of Chemistry, University of Texas at Dallas, Richardson, Texas
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas.,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas.,Veterans Affairs North Texas Healthcare System, Dallas, Texas
| |
Collapse
|
30
|
Yang J, Zhang LJ, Wang F, Hong T, Liu Z. Molecular imaging of diabetes and diabetic complications: Beyond pancreatic β-cell targeting. Adv Drug Deliv Rev 2019; 139:32-50. [PMID: 30529307 DOI: 10.1016/j.addr.2018.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/28/2018] [Accepted: 11/27/2018] [Indexed: 12/13/2022]
Abstract
Diabetes is a chronic non-communicable disease affecting over 400 million people worldwide. Diabetic patients are at a high risk of various complications, such as cardiovascular, renal, and other diseases. The pathogenesis of diabetes (both type 1 and type 2 diabetes) is associated with a functional impairment of pancreatic β-cells. Consequently, most efforts to manage and prevent diabetes have focused on preserving β-cells and their function. Advances in imaging techniques, such as magnetic resonance imaging, magnetic resonance spectroscopy, positron emission tomography, and single-photon-emission computed tomography, have enabled noninvasive and quantitative detection and characterization of the population and function of β-cells in vivo. These advantages aid in defining and monitoring the progress of diabetes and determining the efficacy of anti-diabetic therapies. Beyond β-cell targeting, molecular imaging of biomarkers associated with the development of diabetes, e.g., lymphocyte infiltration, insulitis, and metabolic changes, may also be a promising strategy for early detection of diabetes, monitoring its progression, and occurrence of complications, as well as facilitating exploration of new therapeutic interventions. Moreover, molecular imaging of glucose uptake, production and excretion in specified tissues is critical for understanding the pathogenesis of diabetes. In the current review, we summarize and discuss recent advances in noninvasive imaging technologies for imaging of biomarkers beyond β-cells for early diagnosis of diabetes, investigation of glucose metabolism, and precise diagnosis and monitoring of diabetic complications for better management of diabetic patients.
Collapse
Affiliation(s)
- Jichun Yang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences Peking University Health Science Center, Key Laboratory of Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Beijing 100191, China.
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Fan Wang
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing 100191, China.
| | - Zhaofei Liu
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
| |
Collapse
|
31
|
Thiagarajan P, Aithal GP. Drug Development for Nonalcoholic Fatty Liver Disease: Landscape and Challenges. J Clin Exp Hepatol 2019; 9:515-521. [PMID: 31516268 PMCID: PMC6728526 DOI: 10.1016/j.jceh.2019.03.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/05/2019] [Indexed: 02/08/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is now the leading cause of chronic liver disease in industrialized economies. With no licensed treatment currently available, together with a growing prevalence that parallels global increases in obesity and type 2 diabetes, NAFLD will dominate the landscape of hepatology for the foreseeable future. A multifaceted etiopathogenesis, paucity of reproducible preclinical models that effectively recreate human NAFLD, and lack of robust surrogate trial endpoints have presented major hurdles in drug discovery and development. Smooth collaboration between bench scientists, biotechnology, pharmaceutical industries, and clinicians will be pivotal to target identification, development of effective therapies, biomarker discovery, and ultimately to bring pipeline drugs to market. This review examines the key challenges remaining in NAFLD drug development, outlines early and late phase clinical trials of candidate treatments, and discusses the journey toward biomarker discovery which may facilitate development of novel endpoints in NAFLD clinical trials, enabling meaningful response to be determined noninvasively.
Collapse
Key Words
- BMI, Body Mass Index
- DGAT, Diacyl Glycerol Acyl Transferase
- ELF, Extended Liver Fibrosis Panel
- FIB-4, Fibrosis 4
- FXR, Farnesoid X Receptor
- HCC, Hepatocellular Carcinoma
- HOMA-IR, Homeostasis Model Assessment of Insulin Resistance
- HVPG, Hepatic Venous Pressure Gradient
- HbA1C, Hemoglobin A1C
- MCD, Methionine-Choline–Deficient Diet
- MRE, MR Elastography
- MRI, Magnetic Resonance Imaging
- MRS, Magnetic Resonance Spectroscopy
- NAFLD
- NAFLD, Nonalcoholic Fatty Liver Disease
- NASH, Nonalcoholic Steatohepatitis
- OCA, Obeticholic Acid
- OGTT, Oral Glucose Tolerance Test
- Pro-C3, Pro-collagen 3
- TE, Transient Elastography
- endpoints
- preclinical models
- targets
- therapeutics
Collapse
Affiliation(s)
| | - Guruprasad P. Aithal
- Address for correspondence: Guruprasad P. Aithal, NIHR Nottingham Digestive Diseases Biomedical Research Centre, University of Nottingham and Nottingham University Hospitals NHS Trust, Nottingham, NG72UH, United Kingdom.
| |
Collapse
|
32
|
Ladd ME, Bachert P, Meyerspeer M, Moser E, Nagel AM, Norris DG, Schmitter S, Speck O, Straub S, Zaiss M. Pros and cons of ultra-high-field MRI/MRS for human application. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 109:1-50. [PMID: 30527132 DOI: 10.1016/j.pnmrs.2018.06.001] [Citation(s) in RCA: 267] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 05/08/2023]
Abstract
Magnetic resonance imaging and spectroscopic techniques are widely used in humans both for clinical diagnostic applications and in basic research areas such as cognitive neuroimaging. In recent years, new human MR systems have become available operating at static magnetic fields of 7 T or higher (≥300 MHz proton frequency). Imaging human-sized objects at such high frequencies presents several challenges including non-uniform radiofrequency fields, enhanced susceptibility artifacts, and higher radiofrequency energy deposition in the tissue. On the other side of the scale are gains in signal-to-noise or contrast-to-noise ratio that allow finer structures to be visualized and smaller physiological effects to be detected. This review presents an overview of some of the latest methodological developments in human ultra-high field MRI/MRS as well as associated clinical and scientific applications. Emphasis is given to techniques that particularly benefit from the changing physical characteristics at high magnetic fields, including susceptibility-weighted imaging and phase-contrast techniques, imaging with X-nuclei, MR spectroscopy, CEST imaging, as well as functional MRI. In addition, more general methodological developments such as parallel transmission and motion correction will be discussed that are required to leverage the full potential of higher magnetic fields, and an overview of relevant physiological considerations of human high magnetic field exposure is provided.
Collapse
Affiliation(s)
- Mark E Ladd
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine, University of Heidelberg, Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany; Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen, Germany.
| | - Peter Bachert
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany.
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
| | - Armin M Nagel
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - David G Norris
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, Netherlands; Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen, Germany.
| | - Sebastian Schmitter
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany.
| | - Oliver Speck
- Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Neurodegenerative Diseases, Magdeburg, Germany; Center for Behavioural Brain Sciences, Magdeburg, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany.
| | - Sina Straub
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Moritz Zaiss
- High-Field Magnetic Resonance Center, Max-Planck-Institute for Biological Cybernetics, Tübingen, Germany.
| |
Collapse
|
33
|
Salnikov OG, Shchepin RV, Chukanov NV, Jaigirdar L, Pham W, Kovtunov KV, Koptyug IV, Chekmenev EY. Effects of Deuteration of 13C-Enriched Phospholactate on Efficiency of Parahydrogen-Induced Polarization by Magnetic Field Cycling. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2018; 122:24740-24749. [PMID: 31447960 PMCID: PMC6707357 DOI: 10.1021/acs.jpcc.8b07365] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We report herein a large-scale (>10 g) synthesis of isotopically enriched 1-13C-phosphoenolpyruvate and 1-13C-phosphoenolpyruvate-d2 for application in hyperpolarized imaging technology. The 1-13C-phosphoenolpyruvate-d2 was synthesized with 57% overall yield (over two steps), and >98% 2H isotopic purity, representing an improvement over the previous report. The same outcome was achieved for 1-13C-phosphoenolpyruvate. These two unsaturated compounds with C=C bonds were employed for parahydrogen-induced polarization via pairwise parahydrogen addition in aqueous medium. We find that deuteration of 1-13C-phosphoenolpyruvate resulted in overall increase of 1H T1 of nascent hyperpolarized protons (4.30 ± 0.04 s versus 2.06 ± 0.01 s) and 1H polarization (~2.5% versus ~0.7%) of the resulting hyperpolarized 1-13C-phospholactate. The nuclear spin polarization of nascent parahydrogen-derived protons was transferred to 1-13C nucleus via magnetic field cycling procedure. The proton T1 increase in hyperpolarized deuterated 1-13C-phospholactate yielded approximately 30% better 13C polarization compared to non-deuterated hyperpolarized 1-13C-phospholactate. Analysis of T1 relaxation revealed that deuteration of 1-13C-phospholactate may have resulted in approximately 3-fold worse H→13C polarization transfer efficiency via magnetic field cycling. Since magnetic field cycling is a key polarization transfer step in the Side-Arm Hydrogenation approach, the presented findings may guide more rationale design of contrast agents using parahydrogen polarization of a broad range of 13C hyperpolarized contrast agents for molecular imaging employing 13C MRI. The hyperpolarized 1-13C-phospholactate-d2 is of biomedical imaging relevance because it undergoes in vivo dephosphorylation and becomes 13C hyperpolarized lactate, which as we show can be detected in the brain using 13C hyperpolarized MRI; an implication for future imaging of neurodegenerative diseases and dementia.
Collapse
Affiliation(s)
- Oleg G. Salnikov
- International Tomography Center, 3A Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Roman V. Shchepin
- Vanderbilt University Institute of Imaging Science (VUIIS)
- Department of Radiology
| | - Nikita V. Chukanov
- International Tomography Center, 3A Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Lamya Jaigirdar
- Vanderbilt University Institute of Imaging Science (VUIIS)
- School of Engineering
| | - Wellington Pham
- Vanderbilt University Institute of Imaging Science (VUIIS)
- Department of Radiology
- Department of Biomedical Engineering
- Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University, Nashville, Tennessee 37232-2310, United
States
| | - Kirill V. Kovtunov
- International Tomography Center, 3A Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Igor V. Koptyug
- International Tomography Center, 3A Institutskaya St., Novosibirsk 630090, Russia
- Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Eduard Y. Chekmenev
- Vanderbilt University Institute of Imaging Science (VUIIS)
- Department of Radiology
- Department of Biomedical Engineering
- Vanderbilt-Ingram Cancer Center (VICC), Vanderbilt University, Nashville, Tennessee 37232-2310, United
States
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute
(KCI), Detroit, Michigan, 48202, United States
- Russian Academy of Sciences, Leninskiy Prospekt 14, Moscow, 119991, Russia
- Corresponding Author:
| |
Collapse
|
34
|
Abstract
Purpose To investigate [11C]acetate PET-surrogate parameter of fatty acid synthase activity—as suitable tool for diagnosis and monitoring of liver steatosis. Methods In this retrospective study, data were obtained from 83 prostatic carcinoma patients from 1/2008 to 1/2014. Mean HU was calculated from unenhanced CT of all patients from liver with liver HU less than 40 as threshold for liver steatosis. SUVmax of the liver and of the blood pool in thoracic aorta (as background for calculation of a liver/background ratio [SUVl/b]) was measured. t test was used with a P < 0.05 considered as statistically significant difference and ROC analysis was used for calculating specificity and sensitivity. Results 19/83 patients (20%) had diagnosis of hepatic steatosis according to CT. Uptake of [11C]acetate was significantly higher in patients with hepatic steatosis as compared to control group (SUVmax 7.96 ± 2.0 vs. 5.48 ± 2.3 [P < 0.001]). There was also a significant correlation between both SUVmax (r = − 0.52, P < 0.001) and SUVl/b (r = − 0.59, P < 0.001) with the density (HU) of the liver. In ROC analysis for detection of liver steatosis SUVmax (threshold: 5.86) had a sensitivity of 94% and specificity of 69% with an AUC of 0.81. Increasing body mass index is correlated with the severity of steatosis. Conclusion We showed for the first time that hepatic steatosis associates with increased [11C]acetate uptake. Also, severity of steatosis correlates with [11C]acetate uptake. [11C]acetate uptake PET seems promising for the assessment of liver steatosis. Electronic supplementary material The online version of this article (10.1007/s00261-018-1558-4) contains supplementary material, which is available to authorized users.
Collapse
|
35
|
De Feyter HM, Behar KL, Corbin ZA, Fulbright RK, Brown PB, McIntyre S, Nixon TW, Rothman DL, de Graaf RA. Deuterium metabolic imaging (DMI) for MRI-based 3D mapping of metabolism in vivo. SCIENCE ADVANCES 2018; 4:eaat7314. [PMID: 30140744 PMCID: PMC6105304 DOI: 10.1126/sciadv.aat7314] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 07/18/2018] [Indexed: 05/04/2023]
Abstract
Currently, the only widely available metabolic imaging technique in the clinic is positron emission tomography (PET) detection of the radioactive glucose analog 2-18F-fluoro-2-deoxy-d-glucose (18FDG). However, 18FDG-PET does not inform on metabolism downstream of glucose uptake and often provides ambiguous results in organs with intrinsic high glucose uptake, such as the brain. Deuterium metabolic imaging (DMI) is a novel, noninvasive approach that combines deuterium magnetic resonance spectroscopic imaging with oral intake or intravenous infusion of nonradioactive 2H-labeled substrates to generate three-dimensional metabolic maps. DMI can reveal glucose metabolism beyond mere uptake and can be used with other 2H-labeled substrates as well. We demonstrate DMI by mapping metabolism in the brain and liver of animal models and human subjects using [6,6'-2H2]glucose or [2H3]acetate. In a rat glioma model, DMI revealed pronounced metabolic differences between normal brain and tumor tissue, with high-contrast metabolic maps depicting the Warburg effect. We observed similar metabolic patterns and image contrast in two patients with a high-grade brain tumor after oral intake of 2H-labeled glucose. Further, DMI used in rat and human livers showed [6,6'-2H2]glucose stored as labeled glycogen. DMI is a versatile, robust, and easy-to-implement technique that requires minimal modifications to existing clinical magnetic resonance imaging scanners. DMI has great potential to become a widespread method for metabolic imaging in both (pre)clinical research and the clinic.
Collapse
Affiliation(s)
- Henk M. De Feyter
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
- Corresponding author. (H.M.D.F.); (R.A.d.G.)
| | - Kevin L. Behar
- Department of Psychiatry, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Zachary A. Corbin
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Robert K. Fulbright
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Peter B. Brown
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Scott McIntyre
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Terence W. Nixon
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Douglas L. Rothman
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Biomedical Engineering, Magnetic Resonance Research Center, Yale University, New Haven, CT 06520, USA
| | - Robin A. de Graaf
- Department of Radiology and Biomedical Imaging, Magnetic Resonance Research Center, Yale University School of Medicine, New Haven, CT 06520, USA
- Department of Biomedical Engineering, Magnetic Resonance Research Center, Yale University, New Haven, CT 06520, USA
- Corresponding author. (H.M.D.F.); (R.A.d.G.)
| |
Collapse
|
36
|
Kidd BE, Mashni JA, Limbach MN, Shi F, Chekmenev EY, Hou Y, Goodson BM. Toward Cleavable Metabolic/pH Sensing "Double Agents" Hyperpolarized by NMR Signal Amplification by Reversible Exchange. Chemistry 2018; 24:10641-10645. [PMID: 29800491 PMCID: PMC6097920 DOI: 10.1002/chem.201802622] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Indexed: 11/05/2022]
Abstract
We show the simultaneous generation of hyperpolarized 13 C-labeled acetate and 15 N-labeled imidazole following spin-relay of hyperpolarization and hydrolysis of the acetyl moiety on 1-13 C-15 N2 -acetylimidazole. Using SABRE-SHEATH (Signal Amplification by Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei), transfer of spin order occurs from parahydrogen to acetylimidazole 15 N atoms and the acetyl 13 C site (≈263-fold enhancement), giving rise to relatively long hyperpolarization lifetimes at 0.3 T (T1 ≈52 s and ≈149 s for 13 C and 15 N, respectively). Immediately following polarization transfer, the 13 C-labeled acetyl group is hydrolytically cleaved to produce hyperpolarized 13 C-acetate/acetic acid (≈140-fold enhancement) and 15 N-imidazole (≈180-fold enhancement), the former with a 13 C T1 of ≈14 s at 0.3 T. Straightforward synthetic routes, efficient spin-relay of SABRE hyperpolarization, and facile bond cleavage open a door to the cheap and rapid generation of long-lived hyperpolarized states within a wide range of molecular targets, including biologically relevant carboxylic acid derivatives, for metabolic and pH imaging.
Collapse
Affiliation(s)
- Bryce E Kidd
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Jamil A Mashni
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Miranda N Limbach
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Fan Shi
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Eduard Y Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, MI, 48202, USA
- Russian Academy of Sciences, Leninskiy Prospekt 14, 119991, Moscow, Russia
| | - Yuqing Hou
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Boyd M Goodson
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, 62901, USA
| |
Collapse
|
37
|
Previs SF, Herath K, Nawrocki AR, Rodriguez CG, Slipetz D, Singh SB, Kang L, Bhat G, Roddy TP, Conarello S, Terebetski J, Erion MD, Kelley DE. Using [ 2H]water to quantify the contribution of de novo palmitate synthesis in plasma: enabling back-to-back studies. Am J Physiol Endocrinol Metab 2018; 315:E63-E71. [PMID: 29351479 DOI: 10.1152/ajpendo.00010.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An increased contribution of de novo lipogenesis (DNL) may play a role in cases of dyslipidemia and adipose accretion; this suggests that inhibition of fatty acid synthesis may affect clinical phenotypes. Since it is not clear whether modulation of one step in the lipogenic pathway is more important than another, the use of tracer methods can provide a deeper level of insight regarding the control of metabolic activity. Although [2H]water is generally considered a reliable tracer for quantifying DNL in vivo (it yields a homogenous and quantifiable precursor labeling), the relatively long half-life of body water is thought to limit the ability of performing repeat studies in the same subjects; this can create a bottleneck in the development and evaluation of novel therapeutics for inhibiting DNL. Herein, we demonstrate the ability to perform back-to-back studies of DNL using [2H]water. However, this work uncovered special circumstances that affect the data interpretation, i.e., it is possible to obtain seemingly negative values for DNL. Using a rodent model, we have identified a physiological mechanism that explains the data. We show that one can use [2H]water to test inhibitors of DNL by performing back-to-back studies in higher species [i.e., treat nonhuman primates with platensimycin, an inhibitor of fatty acid synthase]; studies also demonstrate the unsuitability of [13C]acetate.
Collapse
Affiliation(s)
- Stephen F Previs
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Kithsiri Herath
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Andrea R Nawrocki
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Carlos G Rodriguez
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Deborah Slipetz
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Sheo B Singh
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Ling Kang
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Gowri Bhat
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Thomas P Roddy
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Stacey Conarello
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Jenna Terebetski
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - Mark D Erion
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| | - David E Kelley
- Merck Research Laboratories, Merck & Company, Incorporated, Kenilworth, New Jersey
| |
Collapse
|
38
|
Chukanov N, Salnikov OG, Shchepin RV, Kovtunov KV, Koptyug IV, Chekmenev EY. Synthesis of Unsaturated Precursors for Parahydrogen-Induced Polarization and Molecular Imaging of 1- 13C-Acetates and 1- 13C-Pyruvates via Side Arm Hydrogenation. ACS OMEGA 2018; 3:6673-6682. [PMID: 29978146 PMCID: PMC6026840 DOI: 10.1021/acsomega.8b00983] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 06/08/2018] [Indexed: 05/05/2023]
Abstract
Hyperpolarized forms of 1-13C-acetates and 1-13C-pyruvates are used as diagnostic contrast agents for molecular imaging of many diseases and disorders. Here, we report the synthetic preparation of 1-13C isotopically enriched and pure from solvent acetates and pyruvates derivatized with unsaturated ester moiety. The reported unsaturated precursors can be employed for NMR hyperpolarization of 1-13C-acetates and 1-13C-pyruvates via parahydrogen-induced polarization (PHIP). In this PHIP variant, Side arm hydrogenation (SAH) of unsaturated ester moiety is followed by the polarization transfer from nascent parahydrogen protons to 13C nucleus via magnetic field cycling procedure to achieve hyperpolarization of 13C nuclear spins. This work reports the synthesis of PHIP-SAH precursors: vinyl 1-13C-acetate (55% yield), allyl 1-13C-acetate (70% yield), propargyl 1-13C-acetate (45% yield), allyl 1-13C-pyruvate (60% yield), and propargyl 1-13C-pyruvate (35% yield). Feasibility of PHIP-SAH 13C hyperpolarization was verified by 13C NMR spectroscopy: hyperpolarized allyl 1-13C-pyruvate was produced from propargyl 1-13C-pyruvate with 13C polarization of ∼3.2% in CD3OD and ∼0.7% in D2O. 13C magnetic resonance imaging is demonstrated with hyperpolarized 1-13C-pyruvate in aqueous medium.
Collapse
Affiliation(s)
- Nikita
V. Chukanov
- International
Tomography Center, SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia
- Novosibirsk
State University, Pirogova
Street 2, Novosibirsk 630090, Russia
| | - Oleg G. Salnikov
- International
Tomography Center, SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia
- Novosibirsk
State University, Pirogova
Street 2, Novosibirsk 630090, Russia
| | - Roman V. Shchepin
- Vanderbilt
University Institute of Imaging Science (VUIIS), Department of Radiology,
Department of Biomedical Engineering, and Vanderbilt-Ingram Cancer
Center (VICC), Vanderbilt University, Nashville, Tennessee 37232-2310, United States
| | - Kirill V. Kovtunov
- International
Tomography Center, SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia
- Novosibirsk
State University, Pirogova
Street 2, Novosibirsk 630090, Russia
| | - Igor V. Koptyug
- International
Tomography Center, SB RAS, Institutskaya Street 3A, Novosibirsk 630090, Russia
- Novosibirsk
State University, Pirogova
Street 2, Novosibirsk 630090, Russia
| | - Eduard Y. Chekmenev
- Vanderbilt
University Institute of Imaging Science (VUIIS), Department of Radiology,
Department of Biomedical Engineering, and Vanderbilt-Ingram Cancer
Center (VICC), Vanderbilt University, Nashville, Tennessee 37232-2310, United States
- Russian
Academy of Sciences, Leninskiy Prospekt 14, Moscow 119991, Russia
- Department
of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan 48202, United States
- E-mail:
| |
Collapse
|
39
|
Kahl S, Nowotny B, Strassburger K, Bierwagen A, Klüppelholz B, Hoffmann B, Giani G, Nowotny PJ, Wallscheid F, Hatziagelaki E, Pacini G, Hwang JH, Roden M. Amino Acid and Fatty Acid Levels Affect Hepatic Phosphorus Metabolite Content in Metabolically Healthy Humans. J Clin Endocrinol Metab 2018; 103:460-468. [PMID: 29140513 DOI: 10.1210/jc.2017-01773] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/08/2017] [Indexed: 02/13/2023]
Abstract
OBJECTIVE Hepatic energy metabolism negatively relates to insulin resistance and liver fat content in patients with type 2 diabetes, but its role in metabolically healthy humans is unclear. We hypothesized that intrahepatocellular γ-adenosine triphosphate (γATP) and inorganic phosphate (Pi) concentrations exhibit similar associations with insulin sensitivity in nondiabetic, nonobese volunteers. DESIGN A total of 76 participants underwent a four-point sampling, 75-g oral glucose tolerance test (OGTT), as well as in vivo31P/1H magnetic resonance spectroscopy. In 62 of them, targeted plasma metabolomic profiling was performed. Pearson correlation analyses were performed for the dependent variables γATP and Pi. RESULTS Adjusted for age, sex, and body mass index (BMI), hepatic γATP and Pi related to 2-hour OGTT glucose (r = 0.25 and r = 0.27, both P < 0.05), and Pi further associated with nonesterified fatty acids (NEFAs; r = 0.28, P < 0.05). However, neither γATP nor Pi correlated with several measures of insulin sensitivity. Hepatic γATP correlated with circulating leucine (r = 0.42, P < 0.001) and Pi with C16:1 fatty acids palmitoleic acid and C16:1w5 (r = 0.28 and 0.30, respectively, P < 0.01), as well as with δ-9-desaturase index (r = 0.33, P < 0.05). Only the association of γATP with leucine remained important after correction for multiple testing. Leucine and palmitoleic acid, together with age, sex, and BMI, accounted for 26% and for 15% of the variabilities in γATP and Pi, respectively. CONCLUSIONS Specific circulating amino acids and NEFAs, but not measures of insulin sensitivity, partly affect hepatic phosphorus metabolites, suggesting mutual interaction between hepatic energy metabolism and circulating metabolites in nondiabetic humans.
Collapse
Affiliation(s)
- Sabine Kahl
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Bettina Nowotny
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Klaus Strassburger
- German Center for Diabetes Research, München-Neuherberg, Germany
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| | - Alessandra Bierwagen
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Birgit Klüppelholz
- German Center for Diabetes Research, München-Neuherberg, Germany
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| | - Barbara Hoffmann
- Institute for Occupational, Social and Environmental Medicine, Medical Faculty, Düsseldorf, Germany
| | - Guido Giani
- German Center for Diabetes Research, München-Neuherberg, Germany
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| | - Peter J Nowotny
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Franziska Wallscheid
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Erifili Hatziagelaki
- 2nd Department of Internal Medicine, Research Institute and Diabetes Center, Athens University, "Attikon" University General Hospital, Athens, Greece
| | - Giovanni Pacini
- Metabolic Unit, Institute of Neuroscience, Consiglio Nazionale delle Ricerche, Padova, Italy
| | - Jong-Hee Hwang
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Michael Roden
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| |
Collapse
|
40
|
Abstract
Adipose tissue and liver are central tissues in whole body energy metabolism. Their composition, structure, and function can be noninvasively imaged using a variety of measurement techniques that provide a safe alternative to an invasive biopsy. Imaging of adipose tissue is focused on quantitating the distribution of adipose tissue in subcutaneous and intra-abdominal (visceral) adipose tissue depots. Also, detailed subdivisions of adipose tissue can be distinguished with modern imaging techniques. Adipose tissue (or adipocyte) accumulation or infiltration of other organs can also be imaged, with intramuscular adipose tissue a common example. Although liver fat content is now accurately imaged using standard magnetic resonance imaging (MRI) techniques, inflammation and fibrosis are more difficult to determine noninvasively. Liver imaging efforts are therefore concerted on developing accurate imaging markers of liver fibrosis and inflammatory status. Magnetic resonance elastography (MRE) is presently the most reliable imaging technique for measuring liver fibrosis but requires an external device for introduction of shear waves to the liver. Methods using multiparametric diffusion, perfusion, relaxometry, and hepatocyte-specific MRI contrast agents may prove to be more easily implemented by clinicians, provided they reach similar accuracy as MRE. Adipose tissue imaging is experiencing a revolution with renewed interest in characterizing and identifying distinct adipose depots, among them brown adipose tissue. Magnetic resonance spectroscopy provides an interesting yet underutilized way of imaging adipose tissue metabolism through its fatty acid composition. Further studies may shed light on the role of fatty acid composition in different depots and why saturated fat in subcutaneous adipose tissue is a marker of high insulin sensitivity.
Collapse
Affiliation(s)
- Jesper Lundbom
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Düsseldorf, Germany
- HUS Medical Imaging Center, Radiology, Helsinki University Central Hospital, University of Helsinki, Finland
| |
Collapse
|
41
|
Kumar V, Hsueh WA, Raman SV. Multiorgan, Multimodality Imaging in Cardiometabolic Disease. Circ Cardiovasc Imaging 2017; 10:CIRCIMAGING.117.005447. [PMID: 29122843 DOI: 10.1161/circimaging.117.005447] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cardiometabolic disease, spanning conditions such as obesity to type 2 diabetes mellitus with excess cardiovascular risk, represents a major public health burden. Advances in preclinical translational science point to potential targets across multiple organ systems for early intervention to improve cardiometabolic health. Validation in clinical trials and translation to care would benefit from in vivo diagnostic techniques that facilitate therapeutic advancements. This review provides a state-of-the-art, multimodality perspective spanning the multiple organ systems that contribute to cardiometabolic disease.
Collapse
Affiliation(s)
- Vidhya Kumar
- From the Ohio State University Davis Heart and Lung Research Institute, Columbus (V.K., W.A.H., S.V.R.); and Division of Endocrinology, Diabetes & Metabolism, Ohio State University, Columbus (W.A.H.)
| | - Willa A Hsueh
- From the Ohio State University Davis Heart and Lung Research Institute, Columbus (V.K., W.A.H., S.V.R.); and Division of Endocrinology, Diabetes & Metabolism, Ohio State University, Columbus (W.A.H.)
| | - Subha V Raman
- From the Ohio State University Davis Heart and Lung Research Institute, Columbus (V.K., W.A.H., S.V.R.); and Division of Endocrinology, Diabetes & Metabolism, Ohio State University, Columbus (W.A.H.).
| |
Collapse
|
42
|
Pichumani K, Mashimo T, Vemireddy V, Ijare OB, Mickey BE, Malloy CR, Marin-Valencia I, Baskin DS, Bachoo RM, Maher EA. Measurement of 13 C turnover into glutamate and glutamine pools in brain tumor patients. FEBS Lett 2017; 591:3548-3554. [PMID: 28963851 DOI: 10.1002/1873-3468.12867] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 09/18/2017] [Indexed: 12/20/2022]
Abstract
Malignant brain tumors are known to utilize acetate as an alternate carbon source in the citric acid cycle for their bioenergetics. 13 C NMR-based isotopomer analysis has been used to measure turnover of 13 C-acetate carbons into glutamate and glutamine pools in tumors. Plasma from the patients infused with [1,2-13 C]acetate further revealed the presence of 13 C isotopomers of glutamine, glucose, and lactate in the circulation that were generated due to metabolism of [1,2-13 C]acetate by peripheral organs. In the tumor cells, [4-13 C] and [3,4-13 C]glutamate and glutamine isotopomers were generated from blood-borne 13 C-labeled glucose and lactate which were formed due to [1,2-13 C[acetate metabolism of peripheral tissues. [4,5-13 C] and [3,4,5-13 C]glutamate and glutamine isotopomers were produced from [1,2-13 C]acetyl-CoA that was derived from direct oxidation of [1,2-13 C] acetate in the tumor. Major portion of C4 13 C fractional enrichment of glutamate (93.3 ± 0.02%) and glutamine (90.9 ± 0.03%) were derived from [1,2-13 C]acetate-derived acetyl-CoA.
Collapse
Affiliation(s)
- Kumar Pichumani
- Department of Neurosurgery and Houston Methodist Research Institute, Kenneth R. Peak Brain and Pituitary Tumor Treatment Center at Houston Methodist Hospital, Houston, TX, USA.,Weill Cornell Medical College, New York, NY, USA
| | - Tomoyuki Mashimo
- Simmons Cancer Center, Dallas, TX, USA.,Annette G. Strauss Center for Neuro-Oncology, Dallas, TX, USA
| | - Vamsidhara Vemireddy
- Annette G. Strauss Center for Neuro-Oncology, Dallas, TX, USA.,Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - Omkar B Ijare
- Department of Neurosurgery and Houston Methodist Research Institute, Kenneth R. Peak Brain and Pituitary Tumor Treatment Center at Houston Methodist Hospital, Houston, TX, USA
| | - Bruce E Mickey
- Department of Neurological Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Craig R Malloy
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA.,Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, USA.,Veterans Affairs North Texas HealthCare System, Lancaster, TX, USA
| | - Isaac Marin-Valencia
- Pediatric Brain Disease Laboratory, The Rockefeller University, New York, NY, USA
| | - David S Baskin
- Department of Neurosurgery and Houston Methodist Research Institute, Kenneth R. Peak Brain and Pituitary Tumor Treatment Center at Houston Methodist Hospital, Houston, TX, USA.,Weill Cornell Medical College, New York, NY, USA
| | - Robert M Bachoo
- Simmons Cancer Center, Dallas, TX, USA.,Annette G. Strauss Center for Neuro-Oncology, Dallas, TX, USA.,Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Neurology and Neurotherapeutics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Elizabeth A Maher
- Simmons Cancer Center, Dallas, TX, USA.,Annette G. Strauss Center for Neuro-Oncology, Dallas, TX, USA.,Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Neurology and Neurotherapeutics, UT Southwestern Medical Center, Dallas, TX, USA
| |
Collapse
|
43
|
Non-invasive assessment of hepatic mitochondrial metabolism by positional isotopomer NMR tracer analysis (PINTA). Nat Commun 2017; 8:798. [PMID: 28986525 PMCID: PMC5630596 DOI: 10.1038/s41467-017-01143-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 08/22/2017] [Indexed: 01/03/2023] Open
Abstract
Hepatic mitochondria play a central role in the regulation of intermediary metabolism and maintenance of normoglycemia, and there is great interest in assessing rates of hepatic mitochondrial citrate synthase flux (VCS) and pyruvate carboxylase flux (VPC) in vivo. Here, we show that a positional isotopomer NMR tracer analysis (PINTA) method can be used to non-invasively assess rates of VCS and VPC fluxes using a combined NMR/gas chromatography-mass spectrometry analysis of plasma following infusion of [3-13C]lactate and glucose tracer. PINTA measures VCS and VPC fluxes over a wide range of physiological conditions with minimal pyruvate cycling and detects increased hepatic VCS following treatment with a liver-targeted mitochondrial uncoupler. Finally, validation studies in humans demonstrate that the VPC/VCS ratio measured by PINTA is similar to that determined by in vivo NMR spectroscopy. This method will provide investigators with a relatively simple tool to non-invasively examine the role of altered hepatic mitochondrial metabolism. Liver mitochondrial metabolism plays an important role for glucose and lipid homeostasis and its alterations contribute to metabolic disorders, including fatty liver and diabetes. Here Perry et al. develop a method for the measurement of hepatic fluxes by using lactate and glucose tracers in combination with NMR spectroscopy.
Collapse
|
44
|
Traussnigg S, Kienbacher C, Gajdošík M, Valkovič L, Halilbasic E, Stift J, Rechling C, Hofer H, Steindl‐Munda P, Ferenci P, Wrba F, Trattnig S, Krššák M, Trauner M. Ultra-high-field magnetic resonance spectroscopy in non-alcoholic fatty liver disease: Novel mechanistic and diagnostic insights of energy metabolism in non-alcoholic steatohepatitis and advanced fibrosis. Liver Int 2017; 37:1544-1553. [PMID: 28544208 PMCID: PMC5638103 DOI: 10.1111/liv.13451] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND & AIMS With the rising prevalence of non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) non-invasive tools obtaining pathomechanistic insights to improve risk stratification are urgently needed. We therefore explored high- and ultra-high-field magnetic resonance spectroscopy (MRS) to obtain novel mechanistic and diagnostic insights into alterations of hepatic lipid, cell membrane and energy metabolism across the spectrum of NAFLD. METHODS MRS and liver biopsy were performed in 30 NAFLD patients with NAFL (n=8) or NASH (n=22). Hepatic lipid content and composition were measured using 3-Tesla proton (1 H)-MRS. 7-Tesla phosphorus (31 P)-MRS was applied to determine phosphomonoester (PME) including phosphoethanolamine (PE), phosphodiester (PDE) including glycerophosphocholine (GPC), phosphocreatine (PCr), nicotinamide adenine dinucleotide phosphate (NADPH), inorganic phosphate (Pi), γ-ATP and total phosphorus (TP). Saturation transfer technique was used to quantify hepatic ATP flux. RESULTS Hepatic steatosis in 1 H-MRS highly correlated with histology (P<.001) showing higher values in NASH than NAFL (P<.001) without differences in saturated or unsaturated fatty acid indices. PE/TP ratio increased with advanced fibrosis (F3/4) (P=.002) whereas GPC/PME+PDE decreased (P=.05) compared to no/mild fibrosis (F0-2). γ-ATP/TP was lower in advanced fibrosis (P=.049), while PCr/TP increased (P=.01). NADPH/TP increased with higher grades of ballooning (P=.02). Pi-to-ATP exchange rate constant (P=.003) and ATP flux (P=.001) were lower in NASH than NAFL. CONCLUSIONS Ultra-high-field MRS, especially saturation transfer technique uncovers changes in energy metabolism including dynamic ATP flux in inflammation and fibrosis in NASH. Non-invasive profiling by MRS appears feasible and may assist further mechanistic and therapeutic studies in NAFLD/NASH.
Collapse
Affiliation(s)
- Stefan Traussnigg
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Christian Kienbacher
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Martin Gajdošík
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria
| | - Ladislav Valkovič
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria,Department of Imaging MethodsInstitute of Measurement ScienceSlovak Academy of SciencesBratislavaSlovakia
| | - Emina Halilbasic
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Judith Stift
- Department of Clinical PathologyMedical University of ViennaViennaAustria
| | - Christian Rechling
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Harald Hofer
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Petra Steindl‐Munda
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Peter Ferenci
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Fritz Wrba
- Department of Clinical PathologyMedical University of ViennaViennaAustria
| | - Siegfried Trattnig
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria
| | - Martin Krššák
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria,Division of Endocrinology and MetabolismDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Michael Trauner
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| |
Collapse
|
45
|
McCullough A, Previs S, Kasumov T. Stable isotope-based flux studies in nonalcoholic fatty liver disease. Pharmacol Ther 2017; 181:22-33. [PMID: 28720429 DOI: 10.1016/j.pharmthera.2017.07.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and is associated with the worldwide epidemics of obesity, diabetes and cardiovascular diseases. NAFLD ranges from benign fat accumulation in the liver (steatosis) to non-alcoholic steatohepatitis (NASH), and cirrhosis which can progress to hepatocellular carcinoma and liver failure. Mass spectrometry and magnetic resonance spectroscopy-coupled stable isotope-based flux studies provide new insights into the understanding of NAFLD pathogenesis and the disease progression. This review focuses mainly on the utilization of mass spectrometry-based methods for the understanding of metabolic abnormalities in the different stages of NAFLD. For example, stable isotope-based flux studies demonstrated multi-organ insulin resistance, dysregulated glucose, lipids and lipoprotein metabolism in patients with NAFLD. We also review recent developments in the stable isotope-based technologies for the study of mitochondrial dysfunction, oxidative stress and fibrogenesis in NAFLD. We highlight the limitations of current methodologies, discuss the emerging areas of research in this field, and future directions for the applications of stable isotopes to study NAFLD and its complications.
Collapse
Affiliation(s)
- Arthur McCullough
- Department of Gastroenterology & Hepatology, Cleveland Clinic, Cleveland, OH, USA
| | | | - Takhar Kasumov
- Department of Gastroenterology & Hepatology, Cleveland Clinic, Cleveland, OH, USA; Department of Pharmaceutical Sciences, College of Pharmacy, Northeast Ohio Medical University, Rootstown, OH, USA.
| |
Collapse
|
46
|
Marshall DD, Powers R. Beyond the paradigm: Combining mass spectrometry and nuclear magnetic resonance for metabolomics. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2017; 100:1-16. [PMID: 28552170 PMCID: PMC5448308 DOI: 10.1016/j.pnmrs.2017.01.001] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 01/04/2017] [Accepted: 01/08/2017] [Indexed: 05/02/2023]
Abstract
Metabolomics is undergoing tremendous growth and is being employed to solve a diversity of biological problems from environmental issues to the identification of biomarkers for human diseases. Nuclear magnetic resonance (NMR) and mass spectrometry (MS) are the analytical tools that are routinely, but separately, used to obtain metabolomics data sets due to their versatility, accessibility, and unique strengths. NMR requires minimal sample handling without the need for chromatography, is easily quantitative, and provides multiple means of metabolite identification, but is limited to detecting the most abundant metabolites (⩾1μM). Conversely, mass spectrometry has the ability to measure metabolites at very low concentrations (femtomolar to attomolar) and has a higher resolution (∼103-104) and dynamic range (∼103-104), but quantitation is a challenge and sample complexity may limit metabolite detection because of ion suppression. Consequently, liquid chromatography (LC) or gas chromatography (GC) is commonly employed in conjunction with MS, but this may lead to other sources of error. As a result, NMR and mass spectrometry are highly complementary, and combining the two techniques is likely to improve the overall quality of a study and enhance the coverage of the metabolome. While the majority of metabolomic studies use a single analytical source, there is a growing appreciation of the inherent value of combining NMR and MS for metabolomics. An overview of the current state of utilizing both NMR and MS for metabolomics will be presented.
Collapse
Affiliation(s)
- Darrell D Marshall
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, United States
| | - Robert Powers
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, United States.
| |
Collapse
|
47
|
Sunny NE, Bril F, Cusi K. Mitochondrial Adaptation in Nonalcoholic Fatty Liver Disease: Novel Mechanisms and Treatment Strategies. Trends Endocrinol Metab 2017; 28:250-260. [PMID: 27986466 DOI: 10.1016/j.tem.2016.11.006] [Citation(s) in RCA: 218] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/09/2016] [Accepted: 11/09/2016] [Indexed: 12/11/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is prevalent in patients with obesity or type 2 diabetes. Nonalcoholic steatohepatitis (NASH), encompassing steatosis with inflammation, hepatocyte injury, and fibrosis, predisposes to cirrhosis, hepatocellular carcinoma, and even cardiovascular disease. In rodent models and humans with NAFLD/NASH, maladaptation of mitochondrial oxidative flux is a central feature of simple steatosis to NASH transition. Induction of hepatic tricarboxylic acid cycle closely mirrors the severity of oxidative stress and inflammation in NASH. Reactive oxygen species generation and inflammation are driven by upregulated, but inefficient oxidative flux and accumulating lipotoxic intermediates. Successful therapies for NASH (weight loss alone or with incretin therapy, or pioglitazone) likely attenuate mitochondrial oxidative flux and halt hepatocellular injury. Agents targeting mitochondrial dysfunction may provide a novel treatment strategy for NAFLD.
Collapse
Affiliation(s)
- Nishanth E Sunny
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, 1600 SW Archer Road, Room H-2, Gainesville, FL 32610, USA
| | - Fernando Bril
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, 1600 SW Archer Road, Room H-2, Gainesville, FL 32610, USA
| | - Kenneth Cusi
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, 1600 SW Archer Road, Room H-2, Gainesville, FL 32610, USA; Malcom Randall Veterans Administration Medical Center, Gainesville, FL, USA.
| |
Collapse
|
48
|
Zhang R, Huang W, Li G, Hu Y. Noninvasive Strategy Based on Real-Time in Vivo Cataluminescence Monitoring for Clinical Breath Analysis. Anal Chem 2017; 89:3353-3361. [DOI: 10.1021/acs.analchem.6b03898] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Runkun Zhang
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Wanting Huang
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Gongke Li
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Yufei Hu
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| |
Collapse
|
49
|
Sookoian S, Flichman D, Scian R, Rohr C, Dopazo H, Gianotti TF, Martino JS, Castaño GO, Pirola CJ. Mitochondrial genome architecture in non-alcoholic fatty liver disease. J Pathol 2016; 240:437-449. [PMID: 27577682 DOI: 10.1002/path.4803] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/29/2016] [Accepted: 08/18/2016] [Indexed: 12/12/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is associated with mitochondrial dysfunction, a decreased liver mitochondrial DNA (mtDNA) content, and impaired energy metabolism. To understand the clinical implications of mtDNA diversity in the biology of NAFLD, we applied deep-coverage whole sequencing of the liver mitochondrial genomes. We used a multistage study design, including a discovery phase, a phenotype-oriented study to assess the mutational burden in patients with steatohepatitis at different stages of liver fibrosis, and a replication study to validate findings in loci of interest. We also assessed the potential protein-level impact of the observed mutations. To determine whether the observed changes are tissue-specific, we compared the liver and the corresponding peripheral blood entire mitochondrial genomes. The nuclear genes POLG and POLG2 (mitochondrial DNA polymerase-γ) were also sequenced. We observed that the liver mtDNA of patients with NAFLD harbours complex genomes with a significantly higher mutational (1.28-fold) rate and degree of heteroplasmy than in controls. The analysis of liver mitochondrial genomes of patients with different degrees of fibrosis revealed that the disease severity is associated with an overall 1.4-fold increase in mutation rate, including mutations in genes of the oxidative phosphorylation (OXPHOS) chain. Significant differences in gene and protein expression patterns were observed in association with the cumulative number of OXPHOS polymorphic sites. We observed a high degree of homology (∼98%) between the blood and liver mitochondrial genomes. A missense POLG p.Gln1236His variant was associated with liver mtDNA copy number. In conclusion, we have demonstrated that OXPHOS genes contain the highest number of hotspot positions associated with a more severe phenotype. The variability of the mitochondrial genomes probably originates from a common germline source; hence, it may explain a fraction of the 'missing heritability' of NAFLD. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Silvia Sookoian
- Department of Clinical and Molecular Hepatology, Institute of Medical Research A Lanari-IDIM, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Diego Flichman
- Department of Virology, School of Pharmacy and Biochemistry, University of Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Romina Scian
- Department of Clinical and Molecular Hepatology, Institute of Medical Research A Lanari-IDIM, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina.,Department of Molecular Genetics and Biology of Complex Diseases, Institute of Medical Research A Lanari-IDIM, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Cristian Rohr
- Biomedical Genomics and Evolution Laboratory. Ecology, Genetics and Evolution Department, Faculty of Science, IEGEBA, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Hernán Dopazo
- Biomedical Genomics and Evolution Laboratory. Ecology, Genetics and Evolution Department, Faculty of Science, IEGEBA, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Tomas Fernández Gianotti
- Department of Molecular Genetics and Biology of Complex Diseases, Institute of Medical Research A Lanari-IDIM, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Julio San Martino
- Department of Pathology, Hospital Diego Thompson, San Martin, Buenos Aires, Argentina
| | - Gustavo O Castaño
- Liver Unit, Medicine and Surgery Department, Hospital Abel Zubizarreta, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Carlos J Pirola
- Department of Molecular Genetics and Biology of Complex Diseases, Institute of Medical Research A Lanari-IDIM, University of Buenos Aires - National Scientific and Technical Research Council (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| |
Collapse
|
50
|
Rines AK, Sharabi K, Tavares CDJ, Puigserver P. Targeting hepatic glucose metabolism in the treatment of type 2 diabetes. Nat Rev Drug Discov 2016; 15:786-804. [PMID: 27516169 DOI: 10.1038/nrd.2016.151] [Citation(s) in RCA: 232] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Type 2 diabetes mellitus is characterized by the dysregulation of glucose homeostasis, resulting in hyperglycaemia. Although current diabetes treatments have exhibited some success in lowering blood glucose levels, their effect is not always sustained and their use may be associated with undesirable side effects, such as hypoglycaemia. Novel antidiabetic drugs, which may be used in combination with existing therapies, are therefore needed. The potential of specifically targeting the liver to normalize blood glucose levels has not been fully exploited. Here, we review the molecular mechanisms controlling hepatic gluconeogenesis and glycogen storage, and assess the prospect of therapeutically targeting associated pathways to treat type 2 diabetes.
Collapse
Affiliation(s)
- Amy K Rines
- Department of Cancer Biology, Dana-Farber Cancer Institute, and Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Kfir Sharabi
- Department of Cancer Biology, Dana-Farber Cancer Institute, and Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Clint D J Tavares
- Department of Cancer Biology, Dana-Farber Cancer Institute, and Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Pere Puigserver
- Department of Cancer Biology, Dana-Farber Cancer Institute, and Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| |
Collapse
|