1
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Ma EH, Dahabieh MS, DeCamp LM, Kaymak I, Kitchen-Goosen SM, Roy DG, Verway MJ, Johnson RM, Samborska B, Scullion CA, Steadman M, Vos M, Roddy TP, Krawczyk CM, Williams KS, Sheldon RD, Jones RG. 13C metabolite tracing reveals glutamine and acetate as critical in vivo fuels for CD8 + T cells. bioRxiv 2023:2023.06.09.544407. [PMID: 37333111 PMCID: PMC10274878 DOI: 10.1101/2023.06.09.544407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Infusion of 13C-labeled metabolites provides a gold-standard for understanding the metabolic processes used by T cells during immune responses in vivo. Through infusion of 13C-labeled metabolites (glucose, glutamine, acetate) in Listeria monocytogenes (Lm)-infected mice, we demonstrate that CD8+ T effector (Teff) cells utilize metabolites for specific pathways during specific phases of activation. Highly proliferative early Teff cells in vivo shunt glucose primarily towards nucleotide synthesis and leverage glutamine anaplerosis in the tricarboxylic acid (TCA) cycle to support ATP and de novo pyrimidine synthesis. Additionally, early Teff cells rely on glutamic-oxaloacetic transaminase 1 (Got1)-which regulates de novo aspartate synthesis-for effector cell expansion in vivo. Importantly, Teff cells change fuel preference over the course of infection, switching from glutamine- to acetate-dependent TCA cycle metabolism late in infection. This study provides insights into the dynamics of Teff metabolism, illuminating distinct pathways of fuel consumption associated with Teff cell function in vivo.
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Affiliation(s)
- Eric H. Ma
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | - Michael S. Dahabieh
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | - Lisa M. DeCamp
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Irem Kaymak
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | - Susan M. Kitchen-Goosen
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Dominic G. Roy
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal, Montréal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, QC, Canada
| | - Mark J. Verway
- Goodman Cancer Institute, Faculty of Medicine, McGill University, Montréal, QC, Canada
| | | | - Bozena Samborska
- Goodman Cancer Institute, Faculty of Medicine, McGill University, Montréal, QC, Canada
| | - Catherine A. Scullion
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
| | | | - Matthew Vos
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | | | - Connie M. Krawczyk
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Kelsey S. Williams
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
| | - Ryan D. Sheldon
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
- Mass Spectrometry Core, Van Andel Institute, Grand Rapids, MI, USA
| | - Russell G. Jones
- Department of Metabolism and Nutritional Programming, Van Andel Institute, Grand Rapids, MI, USA
- Metabolism and Nutrition (MeNu) Program, Van Andel Institute, Grand Rapids, MI, USA
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2
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Best SA, Gubser PM, Sethumadhavan S, Kersbergen A, Negrón Abril YL, Goldford J, Sellers K, Abeysekera W, Garnham AL, McDonald JA, Weeden CE, Anderson D, Pirman D, Roddy TP, Creek DJ, Kallies A, Kingsbury G, Sutherland KD. Glutaminase inhibition impairs CD8 T cell activation in STK11-/Lkb1-deficient lung cancer. Cell Metab 2022; 34:874-887.e6. [PMID: 35504291 DOI: 10.1016/j.cmet.2022.04.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 01/28/2022] [Accepted: 04/08/2022] [Indexed: 12/13/2022]
Abstract
The tumor microenvironment (TME) contains a rich source of nutrients that sustains cell growth and facilitate tumor development. Glucose and glutamine in the TME are essential for the development and activation of effector T cells that exert antitumor function. Immunotherapy unleashes T cell antitumor function, and although many solid tumors respond well, a significant proportion of patients do not benefit. In patients with KRAS-mutant lung adenocarcinoma, KEAP1 and STK11/Lkb1 co-mutations are associated with impaired response to immunotherapy. To investigate the metabolic and immune microenvironment of KRAS-mutant lung adenocarcinoma, we generated murine models that reflect the KEAP1 and STK11/Lkb1 mutational landscape in these patients. Here, we show increased glutamate abundance in the Lkb1-deficient TME associated with CD8 T cell activation in response to anti-PD1. Combination treatment with the glutaminase inhibitor CB-839 inhibited clonal expansion and activation of CD8 T cells. Thus, glutaminase inhibition negatively impacts CD8 T cells activated by anti-PD1 immunotherapy.
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Affiliation(s)
- Sarah A Best
- ACRF Cancer Biology and Stem Cells Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Patrick M Gubser
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
| | | | - Ariena Kersbergen
- ACRF Cancer Biology and Stem Cells Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | | | | | | | - Waruni Abeysekera
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia; Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Alexandra L Garnham
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia; Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Jackson A McDonald
- ACRF Cancer Biology and Stem Cells Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Clare E Weeden
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia; Personalised Oncology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Dovile Anderson
- Monash Proteomics and Metabolomics Facility, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | | | | | - Darren J Creek
- Monash Proteomics and Metabolomics Facility, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Axel Kallies
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
| | | | - Kate D Sutherland
- ACRF Cancer Biology and Stem Cells Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
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3
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Bambouskova M, Potuckova L, Paulenda T, Kerndl M, Mogilenko DA, Lizotte K, Swain A, Hayes S, Sheldon RD, Kim H, Kapadnis U, Ellis AE, Isaguirre C, Burdess S, Laha A, Amarasinghe GK, Chubukov V, Roddy TP, Diamond MS, Jones RJ, Simons DM, Artyomov MN. -Itaconate confers tolerance to late NLRP3 inflammasome activation. The Journal of Immunology 2021. [DOI: 10.4049/jimmunol.206.supp.15.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Abstract
Itaconate is a unique regulatory metabolite that is induced upon toll-like receptor (TLR) stimulation in myeloid cells. Here, we demonstrate major inflammatory tolerance and cell death phenotypes associated with itaconate production in activated macrophages. We show that endogenous itaconate is a key regulator of the signal 2 of NLRP3 inflammasome activation after long LPS priming which establishes tolerance to late NLRP3 inflammasome activation. We show that itaconate acts synergistically with iNOS and the ability of various TLR ligands to establish NLRP3 inflammasome tolerance depends on the pattern of co-expression of IRG1 and iNOS. Mechanistically, itaconate accumulation upon prolonged inflammatory stimulation prevents full caspase-1 activation and processing of gasdermin D, which we demonstrate to be post-translationally modified by endogenous itaconate. Altogether, our data demonstrate that metabolic rewiring in inflammatory macrophages establishes tolerance to NLRP3 inflammasome activation which, if uncontrolled, can result in pyroptotic cell death and tissue damage.
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4
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Herath KB, Previs SF, Roddy TP, Attygalle AB, González I, Genilloud O, Singh SB. Rapid, Selective, and Sensitive Method for Semitargeted Discovery of Congeneric Natural Products by Liquid Chromatography Tandem Mass Spectrometry. J Nat Prod 2021; 84:814-823. [PMID: 33523676 DOI: 10.1021/acs.jnatprod.0c01190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Natural product congeners serve a useful role in the understanding of natural product biosynthesis and structure-activity relationships. A minor congener with superior activity, selectivity, and modifiable functional groups could serve as a more effective lead structure and replace even the original lead molecule that was used for medicinal chemistry modifications. Currently, no effective method exists to discover targeted congeners rapidly, specifically, and selectively from producing sources. Herein, a new method based on liquid-chromatography tandem-mass spectrometry combination is evaluated for targeted discovery of congeners of platensimycin and platencin from the extracts of Streptomyces platensis. By utilizing a precursor-ion searching protocol, tandem mass spectrometry not only confirmed the presence of known congeners but also provided unambiguous detection of many previously unknown congeners of platensimycin and platencin. This high-throughput and quantitative method can be rapidly and broadly applied for dereplication and congener discovery from a variety of producing sources, even when the targeted compounds are obscured by the presence of unrelated natural products.
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Affiliation(s)
- Kithsiri B Herath
- Merck Research Laboratories, Rahway, Kenilworth, New Jersey 07033, United States
| | - Stephen F Previs
- Merck Research Laboratories, Rahway, Kenilworth, New Jersey 07033, United States
| | - Thomas P Roddy
- Merck Research Laboratories, Rahway, Kenilworth, New Jersey 07033, United States
| | - Athula B Attygalle
- Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, New Jersey 07030, United States
| | - Ignacio González
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Avenida Conocimiento 3, Parque Tecnológico Ciencias de la Salud, 18100 Armilla, Granada, Spain
| | - Olga Genilloud
- Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Avenida Conocimiento 3, Parque Tecnológico Ciencias de la Salud, 18100 Armilla, Granada, Spain
| | - Sheo B Singh
- Merck Research Laboratories, Rahway, Kenilworth, New Jersey 07033, United States
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5
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Bambouskova M, Potuckova L, Paulenda T, Kerndl M, Mogilenko DA, Lizotte K, Swain A, Hayes S, Sheldon RD, Kim H, Kapadnis U, Ellis AE, Isaguirre C, Burdess S, Laha A, Amarasinghe GK, Chubukov V, Roddy TP, Diamond MS, Jones RG, Simons DM, Artyomov MN. Itaconate confers tolerance to late NLRP3 inflammasome activation. Cell Rep 2021; 34:108756. [PMID: 33691097 PMCID: PMC8039864 DOI: 10.1016/j.celrep.2021.108756] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/09/2020] [Accepted: 01/26/2021] [Indexed: 12/21/2022] Open
Abstract
Itaconate is a unique regulatory metabolite that is induced upon Toll-like receptor (TLR) stimulation in myeloid cells. Here, we demonstrate major inflammatory tolerance and cell death phenotypes associated with itaconate production in activated macrophages. We show that endogenous itaconate is a key regulator of the signal 2 of NLR family pyrin domain containing 3 (NLRP3) inflammasome activation after long lipopolysaccharide (LPS) priming, which establishes tolerance to late NLRP3 inflammasome activation. We show that itaconate acts synergistically with inducible nitric oxide synthase (iNOS) and that the ability of various TLR ligands to establish NLRP3 inflammasome tolerance depends on the pattern of co-expression of IRG1 and iNOS. Mechanistically, itaconate accumulation upon prolonged inflammatory stimulation prevents full caspase-1 activation and processing of gasdermin D, which we demonstrate to be post-translationally modified by endogenous itaconate. Altogether, our data demonstrate that metabolic rewiring in inflammatory macrophages establishes tolerance to NLRP3 inflammasome activation that, if uncontrolled, can result in pyroptotic cell death and tissue damage. Bambouskova et al. determine the in vitro phenotype of Irg1−/− macrophages and define itaconate as a key regulator of tolerance to late NLRP3 inflammasome activation.
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Affiliation(s)
- Monika Bambouskova
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Lucie Potuckova
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Tomas Paulenda
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Martina Kerndl
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Institute for Vascular Biology, Centre for Physiology and Pharmacology, Medical University Vienna, 1090 Vienna, Austria; Christian Doppler Laboratory for Arginine Metabolism in Rheumatoid Arthritis and Multiple Sclerosis, 1090 Vienna, Austria
| | - Denis A Mogilenko
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kate Lizotte
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Amanda Swain
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Sebastian Hayes
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Ryan D Sheldon
- Van Andel Research Institute, Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Grand Rapids, MI 49503, USA
| | - Hyeryun Kim
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Unnati Kapadnis
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Abigail E Ellis
- Van Andel Research Institute, Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Grand Rapids, MI 49503, USA
| | - Christine Isaguirre
- Van Andel Research Institute, Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Grand Rapids, MI 49503, USA
| | - Samantha Burdess
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Anwesha Laha
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Victor Chubukov
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Thomas P Roddy
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Michael S Diamond
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA; The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Russell G Jones
- Van Andel Research Institute, Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Grand Rapids, MI 49503, USA
| | - Donald M Simons
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA
| | - Maxim N Artyomov
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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6
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Swain A, Bambouskova M, Kim H, Andhey PS, Duncan D, Auclair K, Chubukov V, Simons DM, Roddy TP, Stewart KM, Artyomov MN. Comparative evaluation of itaconate and its derivatives reveals divergent inflammasome and type I interferon regulation in macrophages. Nat Metab 2020; 2:594-602. [PMID: 32694786 PMCID: PMC7378276 DOI: 10.1038/s42255-020-0210-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/21/2020] [Indexed: 12/21/2022]
Abstract
Following activation, macrophages undergo extensive metabolic rewiring1,2. Production of itaconate through the inducible enzyme IRG1 is a key hallmark of this process3. Itaconate inhibits succinate dehydrogenase4,5, has electrophilic properties6 and is associated with a change in cytokine production4. Here, we compare the metabolic, electrophilic and immunologic profiles of macrophages treated with unmodified itaconate and a panel of commonly used itaconate derivatives to examine its role. Using wild-type and Irg1-/- macrophages, we show that neither dimethyl itaconate, 4-octyl itaconate nor 4-monoethyl itaconate are converted to intracellular itaconate, while exogenous itaconic acid readily enters macrophages. We find that only dimethyl itaconate and 4-octyl itaconate induce a strong electrophilic stress response, in contrast to itaconate and 4-monoethyl itaconate. This correlates with their immunosuppressive phenotype: dimethyl itaconate and 4-octyl itaconate inhibited IκBζ and pro-interleukin (IL)-1β induction, as well as IL-6, IL-10 and interferon-β secretion, in an NRF2-independent manner. In contrast, itaconate treatment suppressed IL-1β secretion but not pro-IL-1β levels and, surprisingly, strongly enhanced lipopolysaccharide-induced interferon-β secretion. Consistently, Irg1-/- macrophages produced lower levels of interferon and reduced transcriptional activation of this pathway. Our work establishes itaconate as an immunoregulatory, rather than strictly immunosuppressive, metabolite and highlights the importance of using unmodified itaconate in future studies.
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Affiliation(s)
- Amanda Swain
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Monika Bambouskova
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| | | | - Prabhakar Sairam Andhey
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Dustin Duncan
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Karine Auclair
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | | | | | | | | | - Maxim N Artyomov
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA.
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7
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Nagaraja R, Olaharski A, Narayanaswamy R, Mahoney C, Pirman D, Gross S, Roddy TP, Popovici-Muller J, Smolen GA, Silverman L. Preclinical toxicology profile of squalene epoxidase inhibitors. Toxicol Appl Pharmacol 2020; 401:115103. [PMID: 32522582 DOI: 10.1016/j.taap.2020.115103] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 04/20/2020] [Accepted: 06/04/2020] [Indexed: 01/20/2023]
Abstract
Small cell lung cancer (SCLC) is a particularly aggressive subset of lung cancer, and identification of new therapeutic options is of significant interest. We recently reported that SCLC cell lines display a specific vulnerability to inhibition of squalene epoxidase (SQLE), an enzyme in the cholesterol biosynthetic pathway that catalyzes the conversion of squalene to 2,3-oxidosqualene. Since it has been reported that SQLE inhibition can result in dermatitis in dogs, we conducted a series of experiments to determine if SQLE inhibitors would be tolerated at exposures predicted to drive maximal efficacy in SCLC tumors. Detailed profiling of the SQLE inhibitor NB-598 showed that dogs did not tolerate predicted efficacious exposures, with dose-limiting toxicity due to gastrointestinal clinical observations, although skin toxicities were also observed. To extend these studies, two SQLE inhibitors, NB-598 and Cmpd-4″, and their structurally inactive analogs, NB-598.ia and Cmpd-4″.ia, were profiled in monkeys. While both active SQLE inhibitors resulted in dose-limiting gastrointestinal toxicity, the structurally similar inactive analogs did not. Collectively, our data demonstrate that significant toxicities arise at exposures well below the predicted levels needed for anti-tumor activity. The on-target nature of the toxicities identified is likely to limit the potential therapeutic utility of SQLE inhibition for the treatment of SCLC.
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Affiliation(s)
- Raj Nagaraja
- Agios Pharmaceuticals, Inc., 88 Sidney St, Cambridge, MA 02139, USA.
| | - Andrew Olaharski
- Agios Pharmaceuticals, Inc., 88 Sidney St, Cambridge, MA 02139, USA
| | | | | | - David Pirman
- Agios Pharmaceuticals, Inc., 88 Sidney St, Cambridge, MA 02139, USA.
| | - Stefan Gross
- Agios Pharmaceuticals, Inc., 88 Sidney St, Cambridge, MA 02139, USA.
| | - Thomas P Roddy
- Agios Pharmaceuticals, Inc., 88 Sidney St, Cambridge, MA 02139, USA.
| | | | | | - Lee Silverman
- Agios Pharmaceuticals, Inc., 88 Sidney St, Cambridge, MA 02139, USA.
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8
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Swain AC, Bambouskova M, Kim H, Duncan D, Auclair K, Chubukov V, Simons DM, Roddy TP, Stewart KM, Artyomov MN. Comparative evaluation of metabolic, electrophilic, and immunologic effects of itaconate and its ester derivatives on macrophage activation. The Journal of Immunology 2020. [DOI: 10.4049/jimmunol.204.supp.73.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Following the discovery of itaconate’s immunoregulatory properties, several ester derivatives of this dicarboxylic acid were designed to further examine its role. Here, we compare the metabolic, electrophilic, and immunologic profiles of macrophages treated with unmodified itaconate and a panel of itaconate derivatives. Using WT and Irg1-deficient macrophages, we show that neither dimethyl itaconate (DI) nor 4-octyl itaconate (4OI) are converted into intracellular itaconate in either resting or TLR-activated cells, 4-monoethyl itaconate (4EI) yields only small quantities of intracellular itaconate, while exogenous itaconic acid readily enters macrophages and accumulates to physiologically relevant amounts. We find that both DI and 4OI induce a strong electrophilic stress response, in contrast to itaconate and 4EI. This correlated with their differential immunological impact: DI and 4OI both inhibited IκBζ induction and IL-6 secretion. In contrast, itaconate treatment had minimal impact on IκBζ, IL-6 and pro-IL-1β levels, but demonstrated a distinct defect in IL-1β secretion. Altogether, this systematic evaluation stresses the importance of using unmodified itaconate in future mechanistic studies.
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9
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Ma EH, Verway MJ, Roy DG, Steadman M, Griss T, Sambroska B, Chubukov V, Roddy TP, Jones RG. Utilization of Stable Isotope Tail-Vein Infusion to Assess Glutamine Utilization by Physiologically Activated CD8+ T cells in vivo. The Journal of Immunology 2020. [DOI: 10.4049/jimmunol.204.supp.155.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Metabolic reprogramming is an essential part of the T cell activation program. Upon activation, T cells undergo dramatic rewiring of their metabolic pathways to promote ATP production and biosynthesis sufficient to support the rapid exponential growth of antigen-specific T cells. The metabolic profile of T cells is shaped by both cell-intrinsic factors, such as genetics and receptor-mediated signaling, and environmental conditions, such as nutrient availability. However, our understanding of T cell metabolism has largely been shaped by studies in vitro, where oxygen and nutrients are in excess. Here, we combined bioenergetic profiling and 13C-glutamine infusion techniques to investigate the metabolism of CD8+ T cells responding to Listeria infection. Similar to in vitro-activated T cells, glutamine is a prominent source of fuel for the TCA cycle during early expansion (3 dpi). However, at later timepoints of infection (6 dpi), the use of glutamine is substantially decreased by Teff cells. Similar to the observation of decreased glucose usage by T cells over the course of infection (Ma et al Immunity 2019). Our data suggests a dynamic flexibly in nutrient usage by T cells in vivo to fuel the different phases of T cell functions, from the early T cell response (3 dpi) to the late (6 dpi). Our work highlights the differences in T cell metabolism in vivo compared to in vitro cultures and a new method to study T cell nutrient utilization in vivo.
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Affiliation(s)
- Eric H Ma
- 1Van Andel Research Institute
- 2McGill Univ., Canada
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10
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Roy DG, Chen J, Mamane V, Ma EH, Muhire BM, Sheldon RD, Shorstova T, Koning R, Johnson RM, Esaulova E, Williams KS, Hayes S, Steadman M, Samborska B, Swain A, Daigneault A, Chubukov V, Roddy TP, Foulkes W, Pospisilik JA, Bourgeois-Daigneault MC, Artyomov MN, Witcher M, Krawczyk CM, Larochelle C, Jones RG. Methionine Metabolism Shapes T Helper Cell Responses through Regulation of Epigenetic Reprogramming. Cell Metab 2020; 31:250-266.e9. [PMID: 32023446 DOI: 10.1016/j.cmet.2020.01.006] [Citation(s) in RCA: 166] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 09/26/2019] [Accepted: 01/12/2020] [Indexed: 12/12/2022]
Abstract
Epigenetic modifications on DNA and histones regulate gene expression by modulating chromatin accessibility to transcription machinery. Here we identify methionine as a key nutrient affecting epigenetic reprogramming in CD4+ T helper (Th) cells. Using metabolomics, we showed that methionine is rapidly taken up by activated T cells and serves as the major substrate for biosynthesis of the universal methyl donor S-adenosyl-L-methionine (SAM). Methionine was required to maintain intracellular SAM pools in T cells. Methionine restriction reduced histone H3K4 methylation (H3K4me3) at the promoter regions of key genes involved in Th17 cell proliferation and cytokine production. Applied to the mouse model of multiple sclerosis (experimental autoimmune encephalomyelitis), dietary methionine restriction reduced the expansion of pathogenic Th17 cells in vivo, leading to reduced T cell-mediated neuroinflammation and disease onset. Our data identify methionine as a key nutritional factor shaping Th cell proliferation and function in part through regulation of histone methylation.
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Affiliation(s)
- Dominic G Roy
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada; Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Jocelyn Chen
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada; Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Victoria Mamane
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada; Department of Neuroscience, Faculty of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Eric H Ma
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada; Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada; Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Brejnev M Muhire
- Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Ryan D Sheldon
- Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Tatiana Shorstova
- The Lady Davis Institute of the Jewish General Hospital, McGill University, Montreal, QC H3T 1E2, Canada; Department of Oncology, McGill University, Montreal, QC, Canada
| | - Rutger Koning
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada
| | - Radia M Johnson
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada
| | - Ekaterina Esaulova
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Human Immunology and Immunotherapy Programs, Washington University at St. Louis, St. Louis, MO 63110, USA
| | - Kelsey S Williams
- Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | | | | | - Bozena Samborska
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada; Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Amanda Swain
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Human Immunology and Immunotherapy Programs, Washington University at St. Louis, St. Louis, MO 63110, USA
| | - Audrey Daigneault
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada
| | | | | | - William Foulkes
- The Lady Davis Institute of the Jewish General Hospital, McGill University, Montreal, QC H3T 1E2, Canada
| | - J Andrew Pospisilik
- Metabolic and Nutritional Programming, Center for Epigenetics, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Marie-Claude Bourgeois-Daigneault
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada; Institut du Cancer de Montréal, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Maxim N Artyomov
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Human Immunology and Immunotherapy Programs, Washington University at St. Louis, St. Louis, MO 63110, USA
| | - Michael Witcher
- The Lady Davis Institute of the Jewish General Hospital, McGill University, Montreal, QC H3T 1E2, Canada; Department of Oncology, McGill University, Montreal, QC, Canada
| | - Connie M Krawczyk
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada; Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada; Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA; Department of Microbiology and Immunology, McGill University, Montreal, QC H3A 2B4, Canada
| | - Catherine Larochelle
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada; Department of Neuroscience, Faculty of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Russell G Jones
- Goodman Cancer Research Centre, McGill University, Montreal, QC H3A 1A3, Canada; Department of Physiology, McGill University, Montreal, QC H3G 1Y6, Canada; Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA.
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11
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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] [What about the content of this article? (0)] [Affiliation(s)] [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.
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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
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12
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McLaren DG, Han S, Murphy BA, Wilsie L, Stout SJ, Zhou H, Roddy TP, Gorski JN, Metzger DE, Shin MK, Reilly DF, Zhou HH, Tadin-Strapps M, Bartz SR, Cumiskey AM, Graham TH, Shen DM, Akinsanya KO, Previs SF, Imbriglio JE, Pinto S. DGAT2 Inhibition Alters Aspects of Triglyceride Metabolism in Rodents but Not in Non-human Primates. Cell Metab 2018; 27:1236-1248.e6. [PMID: 29706567 DOI: 10.1016/j.cmet.2018.04.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 01/12/2018] [Accepted: 04/02/2018] [Indexed: 11/18/2022]
Abstract
Diacylglycerol acyltransferase 2 (DGAT2) catalyzes the final step in triglyceride (TG) synthesis and has been shown to play a role in regulating hepatic very-low-density lipoprotein (VLDL) production in rodents. To explore the potential of DGAT2 as a therapeutic target for the treatment of dyslipidemia, we tested the effects of small-molecule inhibitors and gene silencing both in vitro and in vivo. Consistent with prior reports, chronic inhibition of DGAT2 in a murine model of obesity led to correction of multiple lipid parameters. In contrast, experiments in primary human, rhesus, and cynomolgus hepatocytes demonstrated that selective inhibition of DGAT2 has only a modest effect. Acute and chronic inhibition of DGAT2 in rhesus primates recapitulated the in vitro data yielding no significant effects on production of plasma TG or VLDL apolipoprotein B. These results call into question whether selective inhibition of DGAT2 is sufficient for remediation of dyslipidemia.
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Affiliation(s)
| | - Seongah Han
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA.
| | | | - Larissa Wilsie
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Steven J Stout
- Pharmacology, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Haihong Zhou
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Thomas P Roddy
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | | | - Myung K Shin
- Genetics and Pharmacogenomics, Merck & Co., Inc., Boston, MA 02115, USA
| | - Dermot F Reilly
- Genetics and Pharmacogenomics, Merck & Co., Inc., Boston, MA 02115, USA
| | - Heather H Zhou
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | - Steven R Bartz
- Business Development and Licensing, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | - Thomas H Graham
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Dong-Ming Shen
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Karen O Akinsanya
- Business Development and Licensing, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Stephen F Previs
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | - Shirly Pinto
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA.
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13
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Bambouskova M, Gorvel L, Lampropoulou V, Sergushichev A, Loginicheva E, Johnson K, Korenfeld D, Mathyer ME, Kim H, Huang LH, Duncan D, Bregman H, Keskin A, Santeford A, Apte RS, Sehgal R, Johnson B, Amarasinghe GK, Soares MP, Satoh T, Akira S, Hai T, de Guzman Strong C, Auclair K, Roddy TP, Biller SA, Jovanovic M, Klechevsky E, Stewart KM, Randolph GJ, Artyomov MN. Electrophilic properties of itaconate and derivatives regulate the IκBζ-ATF3 inflammatory axis. Nature 2018; 556:501-504. [PMID: 29670287 PMCID: PMC6037913 DOI: 10.1038/s41586-018-0052-z] [Citation(s) in RCA: 385] [Impact Index Per Article: 64.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 03/16/2018] [Indexed: 01/03/2023]
Abstract
Metabolic regulation has been recognized as a powerful principle guiding immune responses. Inflammatory macrophages undergo extensive metabolic rewiring 1 marked by the production of substantial amounts of itaconate, which has recently been described as an immunoregulatory metabolite 2 . Itaconate and its membrane-permeable derivative dimethyl itaconate (DI) selectively inhibit a subset of cytokines 2 , including IL-6 and IL-12 but not TNF. The major effects of itaconate on cellular metabolism during macrophage activation have been attributed to the inhibition of succinate dehydrogenase2,3, yet this inhibition alone is not sufficient to account for the pronounced immunoregulatory effects observed in the case of DI. Furthermore, the regulatory pathway responsible for such selective effects of itaconate and DI on the inflammatory program has not been defined. Here we show that itaconate and DI induce electrophilic stress, react with glutathione and subsequently induce both Nrf2 (also known as NFE2L2)-dependent and -independent responses. We find that electrophilic stress can selectively regulate secondary, but not primary, transcriptional responses to toll-like receptor stimulation via inhibition of IκBζ protein induction. The regulation of IκBζ is independent of Nrf2, and we identify ATF3 as its key mediator. The inhibitory effect is conserved across species and cell types, and the in vivo administration of DI can ameliorate IL-17-IκBζ-driven skin pathology in a mouse model of psoriasis, highlighting the therapeutic potential of this regulatory pathway. Our results demonstrate that targeting the DI-IκBζ regulatory axis could be an important new strategy for the treatment of IL-17-IκBζ-mediated autoimmune diseases.
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Affiliation(s)
- Monika Bambouskova
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Laurent Gorvel
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Vicky Lampropoulou
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Ekaterina Loginicheva
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Daniel Korenfeld
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Mary Elizabeth Mathyer
- Division of Dermatology, Center for Pharmacogenomics, Center for the Study of Itch, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Li-Hao Huang
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Dustin Duncan
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | | | - Abdurrahman Keskin
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Andrea Santeford
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Rajendra S Apte
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Britney Johnson
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Takashi Satoh
- Host Defense, Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Shizuo Akira
- Host Defense, Immunology Frontier Research Center, Osaka University, Suita, Japan
| | - Tsonwin Hai
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, OH, USA
| | - Cristina de Guzman Strong
- Division of Dermatology, Center for Pharmacogenomics, Center for the Study of Itch, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Karine Auclair
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | | | | | - Marko Jovanovic
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Eynav Klechevsky
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Gwendalyn J Randolph
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Maxim N Artyomov
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.
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14
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Daurio NA, Wang SP, Chen Y, Zhou H, McLaren DG, Roddy TP, Johns DG, Milot D, Kasumov T, Erion MD, Kelley DE, Previs SF. Enhancing Studies of Pharmacodynamic Mechanisms via Measurements of Metabolic Flux: Fundamental Concepts and Guiding Principles for Using Stable Isotope Tracers. J Pharmacol Exp Ther 2017; 363:80-91. [DOI: 10.1124/jpet.117.241091] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Accepted: 06/14/2017] [Indexed: 11/22/2022] Open
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15
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Wang SP, Zhou D, Yao Z, Satapati S, Chen Y, Daurio NA, Petrov A, Shen X, Metzger D, Yin W, Nawrocki AR, Eiermann GJ, Hwa J, Fancourt C, Miller C, Herath K, Roddy TP, Slipetz D, Erion MD, Previs SF, Kelley DE. Quantifying rates of glucose production in vivo following an intraperitoneal tracer bolus. Am J Physiol Endocrinol Metab 2016; 311:E911-E921. [PMID: 27651111 DOI: 10.1152/ajpendo.00182.2016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 09/02/2016] [Accepted: 09/02/2016] [Indexed: 02/05/2023]
Abstract
Aberrant regulation of glucose production makes a critical contribution to the impaired glycemic control that is observed in type 2 diabetes. Although isotopic tracer methods have proven to be informative in quantifying the magnitude of such alterations, it is presumed that one must rely on venous access to administer glucose tracers which therein presents obstacles for the routine application of tracer methods in rodent models. Since intraperitoneal injections are readily used to deliver glucose challenges and/or dose potential therapeutics, we hypothesized that this route could also be used to administer a glucose tracer. The ability to then reliably estimate glucose flux would require attention toward setting a schedule for collecting samples and choosing a distribution volume. For example, glucose production can be calculated by multiplying the fractional turnover rate by the pool size. We have taken a step-wise approach to examine the potential of using an intraperitoneal tracer administration in rat and mouse models. First, we compared the kinetics of [U-13C]glucose following either an intravenous or an intraperitoneal injection. Second, we tested whether the intraperitoneal method could detect a pharmacological manipulation of glucose production. Finally, we contrasted a potential application of the intraperitoneal method against the glucose-insulin clamp. We conclude that it is possible to 1) quantify glucose production using an intraperitoneal injection of tracer and 2) derive a "glucose production index" by coupling estimates of basal glucose production with measurements of fasting insulin concentration; this yields a proxy for clamp-derived assessments of insulin sensitivity of endogenous production.
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Affiliation(s)
| | - Dan Zhou
- Merck Research Laboratories, Kenilworth, New Jersey
| | - Zuliang Yao
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | - Ying Chen
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | | | - Xiaolan Shen
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | - Wu Yin
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | | | - Joyce Hwa
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | - Corin Miller
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | | | | | - Mark D Erion
- Merck Research Laboratories, Kenilworth, New Jersey
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16
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Kozlitina J, Zhou H, Brown PN, Rohm RJ, Pan Y, Ayanoglu G, Du X, Rimmer E, Reilly DF, Roddy TP, Cully DF, Vogt TF, Blom D, Hoek M. Plasma Levels of Risk-Variant APOL1 Do Not Associate with Renal Disease in a Population-Based Cohort. J Am Soc Nephrol 2016; 27:3204-3219. [PMID: 27005919 DOI: 10.1681/asn.2015101121] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 02/10/2016] [Indexed: 12/12/2022] Open
Abstract
Two common missense variants in APOL1 (G1 and G2) have been definitively linked to CKD in black Americans. However, not all individuals with the renal-risk genotype develop CKD, and little is known about how APOL1 variants drive disease. Given the association of APOL1 with HDL particles, which are cleared by the kidney, differences in the level or quality of mutant APOL1‑HDL particles could be causal for disease and might serve as a useful risk stratification marker. We measured plasma levels of G0 (low risk), G1, and G2 APOL1 in 3450 individuals in the Dallas Heart Study using a liquid chromatography-MS method that enabled quantitation of the different variants. Additionally, we characterized native APOL1‑HDL from donors with no or two APOL1 risk alleles by size-exclusion chromatography and analysis of immunopurified APOL1‑HDL particles. Finally, we identified genetic loci associated with plasma APOL1 levels and tested for APOL1-dependent association with renal function. Although we replicated the previous association between APOL1 variant status and renal function in nondiabetic individuals, levels of circulating APOL1 did not associate with microalbuminuria or GFR. Furthermore, the size or known components of APOL1‑HDL did not consistently differ in subjects with the renal-risk genotype. Genetic association studies implicated variants in loci harboring haptoglobin-related protein (HPR), APOL1, and ubiquitin D (UBD) in the regulation of plasma APOL1 levels, but these variants did not associate with renal function. Collectively, these data demonstrate that the risk of renal disease associated with APOL1 is probably not related to circulating levels of the mutant protein.
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Affiliation(s)
- Julia Kozlitina
- McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, Texas; and
| | - Haihong Zhou
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | - Rory J Rohm
- Merck Research Laboratories, Kenilworth, New Jersey
| | - Yi Pan
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | - Xiaoyan Du
- Merck Research Laboratories, Kenilworth, New Jersey
| | - Eric Rimmer
- Merck Research Laboratories, Kenilworth, New Jersey
| | | | | | | | | | - Daniel Blom
- Merck Research Laboratories, Kenilworth, New Jersey
| | - Maarten Hoek
- Merck Research Laboratories, Kenilworth, New Jersey
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17
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McLaren DG, Previs SF, Phair RD, Stout SJ, Xie D, Chen Y, Salituro GM, Xu SS, Castro-Perez JM, Opiteck GJ, Akinsanya KO, Cleary MA, Dansky HM, Johns DG, Roddy TP. Evaluation of CETP activity in vivo under non-steady-state conditions: influence of anacetrapib on HDL-TG flux. J Lipid Res 2015; 57:398-409. [PMID: 26658238 DOI: 10.1194/jlr.m063842] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Indexed: 12/19/2022] Open
Abstract
Studies in lipoprotein kinetics almost exclusively rely on steady-state approaches to modeling. Herein, we have used a non-steady-state experimental design to examine the role of cholesteryl ester transfer protein (CETP) in mediating HDL-TG flux in vivo in rhesus macaques, and therefore, we developed an alternative strategy to model the data. Two isotopomers ([(2)H11] and [(13)C18]) of oleic acid were administered (orally and intravenously, respectively) to serve as precursors for labeling TGs in apoB-containing lipoproteins. The flux of a specific TG (52:2) from these donor lipoproteins to HDL was used as the measure of CETP activity; calculations are also presented to estimate total HDL-TG flux. Based on our data, we estimate that the peak total postprandial TG flux to HDL via CETP is ∼ 13 mg · h(-1) · kg(-1) and show that this transfer was inhibited by 97% following anacetrapib treatment. Collectively, these data demonstrate that HDL TG flux can be used as a measure of CETP activity in vivo. The fact that the donor lipoproteins can be labeled in situ using well-established stable isotope tracer techniques suggests ways to measure this activity for native lipoproteins in free-living subjects under any physiological conditions.
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Affiliation(s)
- David G McLaren
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Stephen F Previs
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Robert D Phair
- Integrative Bioinformatics Inc., Mountain View, CA 94041
| | - Steven J Stout
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Dan Xie
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Ying Chen
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Gino M Salituro
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Suoyu S Xu
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | | | | | | | - Michele A Cleary
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Hayes M Dansky
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Douglas G Johns
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
| | - Thomas P Roddy
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ 07033
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18
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Liu J, McLaren DG, Chen D, Kan Y, Stout SJ, Shen X, Murphy BA, Forrest G, Karanam B, Sonatore L, He S, Roddy TP, Pinto S. Potential mechanism of enhanced postprandial glucagon-like peptide-1 release following treatment with a diacylglycerol acyltransferase 1 inhibitor. Pharmacol Res Perspect 2015; 3:e00193. [PMID: 27022467 PMCID: PMC4777249 DOI: 10.1002/prp2.193] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/01/2015] [Accepted: 09/05/2015] [Indexed: 01/09/2023] Open
Abstract
Studies have demonstrated that blockade of diacylglycerol acyltransferase 1 (DGAT1) leads to prolonged release of glucagon‐like peptide 1 (GLP‐1) after meal challenge. The current study was undertaken to investigate the mechanism of action underlying the elevated levels of GLP‐1 release following pharmacological inhibition of DGAT1. We utilized a potent, specific DGAT1 inhibitor, compound A, to investigate the changes in intestinal lipid profile in a mouse model after oral administration of the compound and challenge with tracer containing fatty meal. [13C18]‐oleic acid and LC‐MS were employed to trace the fate of dietary fatty acids provided as part of a meal challenge in lean mice. Lipid profiles in plasma, proximal to distal segments of intestine, and feces were evaluated at various times following the meal challenge to study the kinetics of fatty acid absorption, synthesis into complex lipids, and excretion. Pharmacological inhibition of DGAT1 led to reduction of postprandial total and newly synthesized triglyceride (TG) excursion and significant increases in TG and FFA levels in the distal portion of intestine enriched with enteroendocrine L cells. Enhanced levels of FFA and cholesteryl ester were observed via fecal fat profiling. DGAT1 inhibition leads to enhancement of carbon flow to the synthesis of phosphatidylcholine within the intestine. DGAT1 inhibition markedly increases levels of TG and FFA in the distal intestine, which could be the predominant contributor to the prolonged and enhanced postprandial GLP‐1 release. Inactivation of DGAT1 could provide potential benefit in the treatment of dysmetabolic diseases.
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Affiliation(s)
- Jinqi Liu
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - David G McLaren
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Dunlu Chen
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Yanqing Kan
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Steven J Stout
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Xiaolan Shen
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Beth Ann Murphy
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Gail Forrest
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Bindhu Karanam
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Lisa Sonatore
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Shuwen He
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
| | - Thomas P Roddy
- Agios Pharmaceuticals 38 Sidney Street Cambridge Massachusetts 02139
| | - Shirly Pinto
- Merck Research Laboratories 2000 Galloping Hill Road Kenilworth New Jersey 07033
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19
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Marzinzik AL, Amstutz R, Bold G, Bourgier E, Cotesta S, Glickman JF, Götte M, Henry C, Lehmann S, Hartwieg JCD, Ofner S, Pellé X, Roddy TP, Rondeau JM, Stauffer F, Stout SJ, Widmer A, Zimmermann J, Zoller T, Jahnke W. Discovery of Novel Allosteric Non-Bisphosphonate Inhibitors of Farnesyl Pyrophosphate Synthase by Integrated Lead Finding. ChemMedChem 2015; 10:1884-91. [PMID: 26381451 DOI: 10.1002/cmdc.201500338] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Indexed: 12/27/2022]
Abstract
Farnesyl pyrophosphate synthase (FPPS) is an established target for the treatment of bone diseases, but also shows promise as an anticancer and anti-infective drug target. Currently available anti-FPPS drugs are active-site-directed bisphosphonate inhibitors, the peculiar pharmacological profile of which is inadequate for therapeutic indications beyond bone diseases. The recent discovery of an allosteric binding site has paved the way toward the development of novel non-bisphosphonate FPPS inhibitors with broader therapeutic potential, notably as immunomodulators in oncology. Herein we report the discovery, by an integrated lead finding approach, of two new chemical classes of allosteric FPPS inhibitors that belong to the salicylic acid and quinoline chemotypes. We present their synthesis, biochemical and cellular activities, structure-activity relationships, and provide X-ray structures of several representative FPPS complexes. These novel allosteric FPPS inhibitors are devoid of any affinity for bone mineral and could serve as leads to evaluate their potential in none-bone diseases.
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Affiliation(s)
| | - René Amstutz
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland.,Conim AG, Oberwiler Kirchweg 4c, 6300, Zug, Switzerland
| | - Guido Bold
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | | | - Simona Cotesta
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - J Fraser Glickman
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland.,High Throughput and Spectroscopy Resource Center, Rockefeller University, New York, NY, 10065, USA
| | - Marjo Götte
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Christelle Henry
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Sylvie Lehmann
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | | | - Silvio Ofner
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Xavier Pellé
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Thomas P Roddy
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland.,Agios, Cambridge, MA, 02139-4169, USA
| | | | - Frédéric Stauffer
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Steven J Stout
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland.,Merck Research Laboratories, 126 E. Lincoln Avenue, Rahway, NJ, 07065, USA
| | - Armin Widmer
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Johann Zimmermann
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland.,Polyphor, Hegenheimermattweg 125, 4123, Allschwil, Switzerland
| | - Thomas Zoller
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland
| | - Wolfgang Jahnke
- Novartis Institutes for BioMedical Research, Basel, 4002, Switzerland.
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20
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Previs SF, Herath K, Castro-Perez J, Mahsut A, Zhou H, McLaren DG, Shah V, Rohm RJ, Stout SJ, Zhong W, Wang SP, Johns DG, Hubbard BK, Cleary MA, Roddy TP. Effect of Error Propagation in Stable Isotope Tracer Studies: An Approach for Estimating Impact on Apparent Biochemical Flux. Methods Enzymol 2015; 561:331-58. [PMID: 26358910 DOI: 10.1016/bs.mie.2015.06.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Stable isotope tracers are widely used to quantify metabolic rates, and yet a limited number of studies have considered the impact of analytical error on estimates of flux. For example, when estimating the contribution of de novo lipogenesis, one typically measures a minimum of four isotope ratios, i.e., the precursor and product labeling pre- and posttracer administration. This seemingly simple problem has 1 correct solution and 80 erroneous outcomes. In this report, we outline a methodology for evaluating the effect of error propagation on apparent physiological endpoints. We demonstrate examples of how to evaluate the influence of analytical error in case studies concerning lipid and protein synthesis; we have focused on (2)H2O as a tracer and contrast different mass spectrometry platforms including GC-quadrupole-MS, GC-pyrolysis-IRMS, LC-quadrupole-MS, and high-resolution FT-ICR-MS. The method outlined herein can be used to determine how to minimize variations in the apparent biology by altering the dose and/or the type of tracer. Likewise, one can facilitate biological studies by estimating the reduction in the noise of an outcome that is expected for a given increase in the number of replicate injections.
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Affiliation(s)
| | | | | | - Ablatt Mahsut
- Merck Research Laboratories, Kenilworth, New Jersey, USA
| | - Haihong Zhou
- Merck Research Laboratories, Kenilworth, New Jersey, USA
| | | | - Vinit Shah
- Merck Research Laboratories, Kenilworth, New Jersey, USA
| | - Rory J Rohm
- Merck Research Laboratories, Kenilworth, New Jersey, USA
| | - Steven J Stout
- Merck Research Laboratories, Kenilworth, New Jersey, USA
| | - Wendy Zhong
- Merck Research Laboratories, Kenilworth, New Jersey, USA
| | | | | | | | | | - Thomas P Roddy
- Merck Research Laboratories, Kenilworth, New Jersey, USA
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21
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Johns DG, Chen Y, Wang SP, Castro-Perez J, Previs SF, Roddy TP. Inhibition of cholesteryl ester transfer protein increases cholesteryl ester content of large HDL independently of HDL-to-HDL homotypic transfer: in vitro vs in vivo comparison using anacetrapib and dalcetrapib. Eur J Pharmacol 2015; 762:256-62. [PMID: 26049012 DOI: 10.1016/j.ejphar.2015.05.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 05/28/2015] [Accepted: 05/29/2015] [Indexed: 10/23/2022]
Abstract
The increase in high density lipoprotein (HDL)-cholesterol observed with cholesteryl ester transfer protein (CETP) inhibition is commonly attributed to blockade of cholesteryl ester (CE) transfer from HDL to low density lipoprotein particles. In vitro, it has been observed that CETP can mediate transfer of CE between HDL particles ("homotypic transfer"), and it is postulated that this contributes to HDL remodeling and generation of anti-atherogenic pre-beta HDL. Inhibition of CETP could limit this beneficial remodeling and reduce pre-beta HDL levels. We observed that anacetrapib does not reduce pre-beta HDL in vivo, but the role of HDL homotypic transfer was not examined. This study evaluated the effects of anacetrapib on homotypic transfer from HDL3 to HDL2 in vivo using deuterium-labeled HDL3, and compared this to in vitro settings, where homotypic transfer was previously described. In vitro, both anacetrapib and dalcetrapib inhibited transfer of CE from HDL3 to HDL2 particles. In CETP transgenic mice, anacetrapib did not inhibit the appearance of labeled CE derived from HDL3 in HDL2 particles, but rather promoted the appearance of labeled CE in HDL2. We concluded that inhibition of CETP by anacetrapib promoted HDL particle remodeling, and does not impair the flux of cholesterol ester into larger HDL particles when studied in vivo, which is not consistent with in vitro observations. We further conclude, therefore, that the in vitro conditions used to examine HDL-to-HDL homotypic transfer may not recapitulate the in vivo condition, where multiple mechanisms contribute to cholesteryl ester flux into and out of the HDL pool.
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Affiliation(s)
- Douglas G Johns
- Departments of Cardiovascular Diseases/Atherosclerosis, Merck & Co., Inc., Kenilworth, NJ, USA.
| | - Ying Chen
- Departments of Cardiovascular Diseases/Atherosclerosis, Merck & Co., Inc., Kenilworth, NJ, USA.
| | - Sheng-Ping Wang
- Departments of Cardiovascular Diseases/Atherosclerosis, Merck & Co., Inc., Kenilworth, NJ, USA.
| | - Jose Castro-Perez
- Departments of Analytical Biochemistry, Merck & Co., Inc., Kenilworth, NJ, USA.
| | - Stephen F Previs
- Departments of Analytical Biochemistry, Merck & Co., Inc., Kenilworth, NJ, USA.
| | - Thomas P Roddy
- Departments of Analytical Biochemistry, Merck & Co., Inc., Kenilworth, NJ, USA.
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22
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Castro-Perez J, Hatcher N, Kofi Karikari N, Wang SP, Mendoza V, Shion H, Millar A, Shockcor J, Towers M, McLaren D, Shah V, Previs S, Akinsanya K, Cleary M, Roddy TP, Johns DG. In vivo isotopically labeled atherosclerotic aorta plaques in ApoE KO mice and molecular profiling by matrix-assisted laser desorption/ionization mass spectrometric imaging. Rapid Commun Mass Spectrom 2014; 28:2471-2479. [PMID: 25303476 DOI: 10.1002/rcm.7039] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 08/31/2014] [Accepted: 09/02/2014] [Indexed: 06/04/2023]
Abstract
RATIONALE The ability to quantify rates of formation, regression and/or remodeling of atherosclerotic plaque should facilitate a better understanding of the pathogenesis and management of cardiovascular disease. In the current study, we coupled a stable isotope labeled tracer protocol with matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to examine spatial and temporal lipid dynamics in atherosclerotic plaque. METHODS To promote plaque formation in the aorta region, ApoE KO mice were fed a high cholesterol diet (0.15% cholesterol) and orally dosed with (2,2,3,4,4,6-d(6))-cholesterol over several weeks. Tissue sections of ~10 µm thickness were analyzed by MALDI-MSI using matrix deposition by either chemical sublimation or acoustic droplet ejection. RESULTS MALDI-MSI yielded distinct spatial distribution information for a variety of lipid classes including specific lysophosphatidylcholines typically associated with atherosclerosis-related tissue damage such as phospholipase 2 (Lp-PLA(2)) that mediate chemotactic responses to inflammation (e.g. LPC 16:0, LPC 18:0 and LPC 18:1) as well as free cholesterol and cholesteryl esters that contribute to atheroma formation. MALDI mass spectra acquired from aorta tissue sections clearly distinguished non-esterified and esterified versions of (2,2,3,4,4,6-d(6))-cholesterol within aortic plaque regions and showed distinct spatial accumulation of the cholesterol tracer. CONCLUSIONS The ability to couple stable isotope based protocols with MALDI-MSI enables a novel strategy to characterize the effects of therapeutic treatments on atherosclerotic plaque formation, regression and potential remodeling of the complex lipid components with high chemical specificity and spatiotemporal information.
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Affiliation(s)
- Jose Castro-Perez
- Merck & Co., Inc, Merck Research Laboratories, Kenilworth, NJ, 07033, USA
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23
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Camus G, Schweiger M, Herker E, Harris C, Kondratowicz AS, Tsou CL, Farese RV, Herath K, Previs SF, Roddy TP, Pinto S, Zechner R, Ott M. The hepatitis C virus core protein inhibits adipose triglyceride lipase (ATGL)-mediated lipid mobilization and enhances the ATGL interaction with comparative gene identification 58 (CGI-58) and lipid droplets. J Biol Chem 2014; 289:35770-80. [PMID: 25381252 DOI: 10.1074/jbc.m114.587816] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Liver steatosis is a common health problem associated with hepatitis C virus (HCV) and an important risk factor for the development of liver fibrosis and cancer. Steatosis is caused by triglycerides (TG) accumulating in lipid droplets (LDs), cellular organelles composed of neutral lipids surrounded by a monolayer of phospholipids. The HCV nucleocapsid core localizes to the surface of LDs and induces steatosis in cultured cells and mouse livers by decreasing intracellular TG degradation (lipolysis). Here we report that core at the surface of LDs interferes with the activity of adipose triglyceride lipase (ATGL), the key lipolytic enzyme in the first step of TG breakdown. Expressing core in livers or mouse embryonic fibroblasts of ATGL(-/-) mice no longer decreases TG degradation as observed in LDs from wild-type mice, supporting the model that core reduces lipolysis by engaging ATGL. Core must localize at LDs to inhibit lipolysis, as ex vivo TG hydrolysis is impaired in purified LDs coated with core but not when free core is added to LDs. Coimmunoprecipitation experiments revealed that core does not directly interact with the ATGL complex but, unexpectedly, increased the interaction between ATGL and its activator CGI-58 as well as the recruitment of both proteins to LDs. These data link the anti-lipolytic activity of the HCV core protein with altered ATGL binding to CGI-58 and the enhanced association of both proteins with LDs.
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Affiliation(s)
- Gregory Camus
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158
| | - Martina Schweiger
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158, Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Eva Herker
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158, UCSF Liver Center, University of California, San Francisco, California 94158, Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology, 20251 Hamburg, Germany
| | - Charles Harris
- UCSF Liver Center, University of California, San Francisco, California 94158, Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, Department of Medicine, University of California, San Francisco, California 94158, Division of Endocrinology Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Andrew S Kondratowicz
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158
| | - Chia-Lin Tsou
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158
| | - Robert V Farese
- UCSF Liver Center, University of California, San Francisco, California 94158, Gladstone Institute of Cardiovascular Disease, San Francisco, California 94158, Department of Medicine, University of California, San Francisco, California 94158, Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158, and
| | - Kithsiri Herath
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Stephen F Previs
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Thomas P Roddy
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Shirly Pinto
- Merck Research Laboratories, Merck and Co., Inc., Kenilworth, New Jersey 07065
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Melanie Ott
- From the Gladstone Institute of Virology and Immunology, San Francisco, California 94158, UCSF Liver Center, University of California, San Francisco, California 94158, Department of Medicine, University of California, San Francisco, California 94158,
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24
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Roddy TP, McLaren DG, Chen Y, Xie D, Dunn K, Kulick A, Szeto D, Forrest G, Albanese K, Donnelly M, Gai C, Gewain A, Lederman H, Jensen KK, Ai X, Vachal P, Akinsanya KO, Cleary MA, Previs SF, Dansky HM, Johns DG. Effects of anacetrapib on plasma lipids, apolipoproteins and PCSK9 in healthy, lean rhesus macaques. Eur J Pharmacol 2014; 740:410-6. [DOI: 10.1016/j.ejphar.2014.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 04/09/2014] [Accepted: 04/10/2014] [Indexed: 01/24/2023]
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25
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Lassman ME, McLaughlin TM, Zhou H, Pan Y, Marcovina SM, Laterza O, Roddy TP. Simultaneous quantitation and size characterization of apolipoprotein(a) by ultra-performance liquid chromatography/mass spectrometry. Rapid Commun Mass Spectrom 2014; 28:1101-1106. [PMID: 24711273 DOI: 10.1002/rcm.6883] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 02/27/2014] [Accepted: 02/27/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Apolipoprotein(a) is a polymorphic glycoprotein covalently bound to apoB100 in Lp(a) particles and has been described to be both atherogenic and prothrombotic, although its exact mechanism of action is not well defined. Apolipoprotein(a) is routinely measured by immunoassays. Unfortunately, the accuracy of the measurement can be affected by the apolipoprotein(a) size (number of kringles) polymorphism in Lp(a) particles. Here we describe an ultra-performance liquid chromatography/mass spectrometry (UPLC/MS) assay that is capable of measuring apolipoprotein(a) concentrations while simultaneously determining the number of kringles present per protein. METHODS Plasma samples were diluted and proteins de-lipidated with deoxycholate prior to tryptic digestion. Distinct tryptic peptides from different regions of apolipoprotein(a) were measured to determine both concentration and the number of kringles present per protein. Separation and quantitation of tryptic peptides is carried out at 700 μL/min using a 1.7 µm C18 column (2.1 × 100 mm) coupled to a Thermo Vantage triple quadrupole (QQQ) mass spectrometer with a heated electrospray ionization (HESI) source. RESULTS This method was compared to established methods for measuring concentration (monoclonal antibody based ELISA) and size (gel-electrophoresis) using 80 plasma samples proved by NWLRL. The slope and r(2) value for the correlation of concentrations were determined to be 0.96 and 0.98, demonstrating excellent agreement of absolute values between the UPLC/MS and ELISA methods. As measured by UPLC/MS, the average kringle number or size is smaller than determined by the electrophoretic method. CONCLUSIONS A single UPLC/MS method was developed capable of measuring apolipoprotein(a) concentration and size (by measuring the number of kringles per protein). This assay passes criteria required for 'fit for purpose' assays including sensitivity, intra and interday reproducibility and freeze/thaw stability. While the agreement between UPLC/MS and ELISA is excellent for concentration and may provide researchers with additional tools for studying apolipoprotein(a), the dissimilarities between UPLC/MS and the electrophoretic method may also be exploited for understanding apolipoprotein(a) structure and function.
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Affiliation(s)
- Michael E Lassman
- Merck Research Laboratories, 126 E. Lincoln Ave., Rahway, NJ, 07065, USA
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26
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Pan Y, Zhou H, Mahsut A, Rohm RJ, Berejnaia O, Price O, Chen Y, Castro-Perez J, Lassman ME, McLaren D, Conway J, Jensen KK, Thomas T, Reyes-Soffer G, Ginsberg HN, Gutstein DE, Cleary M, Previs SF, Roddy TP. Static and turnover kinetic measurement of protein biomarkers involved in triglyceride metabolism including apoB48 and apoA5 by LC/MS/MS. J Lipid Res 2014; 55:1179-87. [PMID: 24694356 DOI: 10.1194/jlr.d047829] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Indexed: 11/20/2022] Open
Abstract
LC/MS quantification of multiple plasma proteins that differ by several orders of magnitude in concentration from a single sample is challenging. We present a strategy that allows the simultaneous determination of the concentration and turnover kinetics of higher and lower abundant proteins from a single digestion mixture. Our attention was directed at a cluster of proteins that interact to affect the absorption and interorgan lipid trafficking. We demonstrate that apos involved in TG metabolism such as apoC2, C3, E, and A4 (micromolar concentration), and apoB48 and apoA5 (single-digit nanomolar concentration) can be quantified from a single digestion mixture. A high degree of correlation between LC/MS and immunobased measurements for apoC2, C3, E, and B48 was observed. Moreover, apoA5 fractional synthesis rate was measured in humans for the first time. Finally, the method can be directly applied to studies involving nonhuman primates because peptide sequences used in the method are conserved between humans and nonhuman primates.
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Affiliation(s)
- Yi Pan
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - Haihong Zhou
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - Ablatt Mahsut
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - Rory J Rohm
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - Olga Berejnaia
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - Olga Price
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - Ying Chen
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | | | | | - David McLaren
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | - James Conway
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | | | | | | | | | | | - Michele Cleary
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
| | | | - Thomas P Roddy
- Merck Research Laboratories, Merck & Co. Inc., Kenilworth, NJ
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27
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Herath KB, Zhong W, Yang J, Mahsut A, Rohm RJ, Shah V, Castro-Perez J, Zhou H, Attygalle AB, Kang L, Singh S, Johns DG, Cleary MA, Hubbard BK, Previs SF, Roddy TP. Determination of low levels of 2H-labeling using high-resolution mass spectrometry: application in studies of lipid flux and beyond. Rapid Commun Mass Spectrom 2014; 28:239-244. [PMID: 24375874 DOI: 10.1002/rcm.6776] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 10/23/2013] [Accepted: 10/27/2013] [Indexed: 06/03/2023]
Abstract
RATIONALE The ability to measure low levels of (2)H-labeling is important in studies of metabolic flux, e.g. one can estimate lipid synthesis by administering (2)H2O and then measuring the incorporation of (2)H into fatty acids. Unfortunately, the analyses are complicated by the presence of more abundant naturally occurring stable isotopes, e.g. (13)C. Conventional approaches rely on coupling gas chromatographic separation of lipids with either quadrupole-mass spectrometry (q-MS) and/or pyrolysis-isotope ratio mass spectrometry (IRMS). The former is limited by high background labeling (primarily from (13)C) whereas the latter is not suitable for routine high-throughput analyses. METHODS We have contrasted the use of continuous flow-pyrolysis-IRMS against high-resolution mass spectrometry (i.e. Qq-FT-ICR MS) for measuring the (2)H-enrichment of fatty acids and peptides. RESULTS In contrast to IRMS, which requires ~30 min per analysis, it is possible to measure the (2)H-enrichment of palmitate via direct infusion high-resolution mass spectrometry (HRMS) in ~3 min per sample. In addition, Qq-FT-ICR MS enabled measurements of the (2)H-enrichment of peptides (which is not possible using IRMS). CONCLUSIONS High-resolution mass spectrometry can be used to measure low levels of (2)H-labeling so we expect that this approach will enhance studies of metabolic flux that rely on (2)H-labeled tracers, e.g. (2)H2O. However, since the high-resolution analyses require greater amounts of a given analyte one potential limitation centers on the overall sensitivity. Presumably, future advances can overcome this barrier.
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28
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Zhou H, Hoek M, Yi P, Rohm RJ, Mahsut A, Brown P, Saunders J, Chmielowski RA, Ren N, Shuster D, Southwick K, Ayanoglu G, Gorman D, Laface D, Santino S, Conway J, Liu Z, Cully D, Cleary M, Roddy TP, Blom D. Rapid detection and quantification of apolipoprotein L1 genetic variants and total levels in plasma by ultra-performance liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Spectrom 2013; 27:2639-2647. [PMID: 24591025 DOI: 10.1002/rcm.6734] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 08/27/2013] [Accepted: 09/10/2013] [Indexed: 06/03/2023]
Abstract
RATIONALE Human genetics studies in African Americans have shown a strong correlation between polymorphisms in the ApoL1 gene and chronic kidney disease (CKD). To gain further insight into the etiology of ApoL1-associated kidney diseases, the determination of circulating levels of both wild type as well as ApoL1 variants could be of significant use. To date, antibodies that discriminate between all three ApoL1 variant forms (wild type, G1 and G2) are not available. We aimed to develop a rapid method for detecting and quantifying ApoL1 variants and total levels in plasma. METHODS Ultra-performance liquid chromatography (UPLC) and tandem mass spectrometry (MS/MS) in multiple-reaction monitoring acquisition mode was used to quantify ApoL1. RESULTS We demonstrated that it is feasible to detect and quantify ApoL1 variants (wild type, G1 and G2), and total ApoL1 concentrations in plasma. ApoL1 genotypes determined by LC/MS agreed perfectly with the traditional method DNA sequencing for 74 human subjects. The method exhibited at least three orders of linearity with a lower limit of quantification of 10 nM. Moreover, the method can readily be multiplexed for the quantification of a panel of protein markers in a single sample. CONCLUSIONS The method reported herein obviates the need to perform DNA genotyping of ApoL1 variants, which is of significant value in cases where stored samples are unsuitable for DNA analysis. More importantly, the method could potentially be of use in the early identification of individuals at risk of developing CKD, and for the stratification of patients for treatment with future ApoL1-modifying therapies.
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Affiliation(s)
- Haihong Zhou
- Merck Research Laboratories, Merck & Co., Inc., Kenilworth, NJ, 07033, USA
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29
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Shah V, Castro-Perez JM, McLaren DG, Herath KB, Previs SF, Roddy TP. Enhanced data-independent analysis of lipids using ion mobility-TOFMSE to unravel quantitative and qualitative information in human plasma. Rapid Commun Mass Spectrom 2013; 27:2195-2200. [PMID: 23996393 DOI: 10.1002/rcm.6675] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 07/02/2013] [Accepted: 07/03/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Lipids are involved in various biochemical and signaling pathways, cell structure and function, and the pathophysiology of many diseases. We took advantage of ion mobility spectrometry (IMS) in conjunction with ultra-performance liquid chromatography (UPLC) and high-resolution mass spectrometry to gain quantitative and deeper qualitative structural insight within a single experiment. METHODS Human plasma lipid extracts were analyzed using an Acquity UPLC system coupled to a Synapt G2-HDMS mass spectrometer system. The ion mobility gas employed was helium for the helium cell (150 mL/min) and nitrogen (80 mL/min) for the T-wave drift tube. The wave height for the T-wave cell was ramped in a linear fashion between 5-40 V. The mass spectra were acquired in an electrospray positive ionization mode. RESULTS We resolved chromatographically co-eluting lipids further by ion mobility tube drift time and then subjected them to low- and high-energy fragmentation without pre-selecting respective precursor species. The fragment ions produced in a high-energy mode were aligned with their precursor ions in a low-energy mode. By aligning intact molecular spectra and fragment spectra for these lipids at a given ion mobility drift time and chromatographic retention time, we were able to obtain much cleaner fragment ion spectra for structural elucidation. For quantitative analysis we obtained a dynamic linear range from 0.002 to 2 µg/mL with and without an additional dimension of IMS. CONCLUSIONS The additional dimension of IMS allowed us to perform quantitative and qualitative analysis within a single experiment in a relatively high-throughput manner thus providing deeper structural insights into lipids of biological interest and resulting in an information-rich dataset.
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Affiliation(s)
- Vinit Shah
- Analytical Biochemistry and Molecular Biomarkers, Merck Research Laboratories, Kenilworth, NJ 07033, USA.
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Wang SP, Daniels E, Chen Y, Castro-Perez J, Zhou H, Akinsanya KO, Previs SF, Roddy TP, Johns DG. In vivo effects of anacetrapib on preβ HDL: improvement in HDL remodeling without effects on cholesterol absorption. J Lipid Res 2013; 54:2858-65. [PMID: 23898048 DOI: 10.1194/jlr.m041541] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Cholesteryl ester transfer protein (CETP) transfers cholesteryl ester and triglyceride between HDL and apoB-containing lipoproteins. Anacetrapib (ANA), a reversible inhibitor of CETP, raises HDL cholesterol and lowers LDL cholesterol in dyslipidemic patients. We previously demonstrated that ANA increases macrophage-to-feces reverse cholesterol transport and fecal cholesterol excretion in hamsters, and increased preβ HDL-dependent cholesterol efflux via ABCA1 in vitro. However, the effects of ANA on in vivo preβ HDL have not been characterized. In vitro, ANA inhibited the formation of preβ, however in ANA-treated dyslipidemic hamsters, preβ HDL levels (measured by two-dimensional gel electrophoresis) were increased, in contrast to in vitro findings. Because changes in plasma preβ HDL have been proposed to potentially affect markers of cholesterol absorption with other CETP inhibitors, a dual stable isotope method was used to directly measure cholesterol absorption in hamsters. ANA treatment of hamsters (on either dyslipidemic or normal diet) had no effect on cholesterol absorption, while dalcetrapib-treated hamsters displayed an increase in cholesterol absorption. Taken together, these data support the notion that ANA promotes preβ HDL functionality in vivo, with no effects on cholesterol absorption.
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Affiliation(s)
- Sheng-Ping Wang
- Department of Atherosclerosis, Merck Research Laboratories, Rahway, NJ 07065
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Han S, Akiyama TE, Previs SF, Herath K, Roddy TP, Jensen KK, Guan HP, Murphy BA, McNamara LA, Shen X, Strapps W, Hubbard BK, Pinto S, Li C, Li J. Effects of small interfering RNA-mediated hepatic glucagon receptor inhibition on lipid metabolism in db/db mice. J Lipid Res 2013; 54:2615-22. [PMID: 23828778 DOI: 10.1194/jlr.m035592] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hepatic glucose overproduction is a major characteristic of type 2 diabetes. Because glucagon is a key regulator for glucose homeostasis, antagonizing the glucagon receptor (GCGR) is a possible therapeutic strategy for the treatment of diabetes mellitus. To study the effect of hepatic GCGR inhibition on the regulation of lipid metabolism, we generated siRNA-mediated GCGR knockdown (si-GCGR) in the db/db mouse. The hepatic knockdown of GCGR markedly reduced plasma glucose levels; however, total plasma cholesterol was increased. The detailed lipid analysis showed an increase in the LDL fraction, and no change in VLDL HDL fractions. Further studies showed that the increase in LDL was the result of over-expression of hepatic lipogenic genes and elevated de novo lipid synthesis. Inhibition of hepatic glucagon signaling via siRNA-mediated GCGR knockdown had an effect on both glucose and lipid metabolism in db/db mice.
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Affiliation(s)
- Seongah Han
- Division of Cardiovascular Disease, Merck Sharp & Dohme Corp., Whitehouse Station, NJ
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Liu J, Gorski JN, Gold SJ, Chen D, Chen S, Forrest G, Itoh Y, Marsh DJ, McLaren DG, Shen Z, Sonatore L, Carballo-Jane E, Craw S, Guan X, Karanam B, Sakaki J, Szeto D, Tong X, Xiao J, Yoshimoto R, Yu H, Roddy TP, Balkovec J, Pinto S. Pharmacological inhibition of diacylglycerol acyltransferase 1 reduces body weight and modulates gut peptide release--potential insight into mechanism of action. Obesity (Silver Spring) 2013; 21:1406-15. [PMID: 23671037 DOI: 10.1002/oby.20193] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 11/11/2012] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Investigation was conducted to understand the mechanism of action of diacylglycerol acyltransferase 1 (DGAT1) using small molecules DGAT1 inhibitors, compounds K and L. DESIGN AND METHODS Biochemical and stable-label tracer approaches were applied to interrogate the functional activities of compounds K and L on TG synthesis and changes of carbon flow. Energy homeostasis and gut peptide release upon DGAT1 inhibition was conducted in mouse and dog models. RESULTS Compounds K and L, dose-dependently inhibits post-prandial TG excursion in mouse and dog models. Weight loss studies in WT and Dgat1(-/-) mice, confirmed that the effects of compound K on body weight loss is mechanism-based. Compounds K and L altered incretin peptide release following oral fat challenge. Immunohistochemical studies with intestinal tissues demonstrate lack of detectable DGAT1 immunoreactivity in enteroendocrine cells. Furthermore, (13) C-fatty acid tracing studies indicate that compound K inhibition of DGAT1 increased the production of phosphatidyl choline (PC). CONCLUSION Treatment with DGAT1 inhibitors improves lipid metabolism and body weight. DGAT1 inhibition leads to enhanced PC production via alternative carbon channeling. Immunohistological studies suggest that DGAT1 inhibitor's effects on plasma gut peptide levels are likely via an indirect mechanism. Overall these data indicate a translational potential towards the clinic.
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Affiliation(s)
- Jinqi Liu
- Merck Research Laboratories, Rahway, New Jersey, USA
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Zhou H, Castro-Perez J, Lassman ME, Thomas T, Li W, McLaughlin T, Dan X, Jumes P, Wagner JA, Gutstein DE, Hubbard BK, Rader DJ, Millar JS, Ginsberg HN, Reyes-Soffer G, Cleary M, Previs SF, Roddy TP. Measurement of apo(a) kinetics in human subjects using a microfluidic device with tandem mass spectrometry. Rapid Commun Mass Spectrom 2013; 27:1294-302. [PMID: 23681806 PMCID: PMC4944116 DOI: 10.1002/rcm.6572] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 02/20/2013] [Accepted: 03/14/2013] [Indexed: 05/15/2023]
Abstract
RATIONALE Apolipoprotein(a) [apo(a)] is the defining protein component of lipoprotein(a) [Lp(a)], an independent risk factor for cardiovascular disease. The regulation of Lp(a) levels in blood is poorly understood in part due to technical challenges in measuring Lp(a) kinetics. Improvements in the ability to readily and reliably measure the kinetics of apo(a) using a stable isotope labeled tracer is expected to facilitate studies of the role of Lp(a) in cardiovascular disease. Since investigators typically determine the isotopic labeling of protein-bound amino acids following acid-catalyzed hydrolysis of a protein of interest [e.g., apo(a)], studies of protein synthesis require extensive protein purification which limits throughput and often requires large sample volumes. We aimed to develop a rapid and efficient method for studying apo(a) kinetics that is suitable for use in studies involving human subjects. METHODS Microfluidic device and tandem mass spectrometry were used to quantify the incorporation of [(2)H3]-leucine tracer into protein-derived peptides. RESULTS We demonstrated that it is feasible to quantify the incorporation of [(2)H3]-leucine tracer into a proteolytic peptide from the non-kringle repeat region of apo(a) in human subjects. Specific attention was directed toward optimizing the multiple reaction monitoring (MRM) transitions, mass spectrometer settings, and chromatography (i.e., critical parameters that affect the sensitivity and reproducibility of isotopic enrichment measurements). The results demonstrated significant advantages with the use of a microfluidic device technology for studying apo(a) kinetics, including enhanced sensitivity relative to conventional micro-flow chromatography, a virtually drift-free elution profile, and a stable and robust electrospray. CONCLUSIONS The technological advances described herein enabled the implementation of a novel method for studying the kinetics of apo(a) in human subjects infused with [(2)H3]-leucine.
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Affiliation(s)
- Haihong Zhou
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Jose Castro-Perez
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Michael E. Lassman
- Clinical Development Laboratory, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | | | - Wenyu Li
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Theresa McLaughlin
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Xie Dan
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Patricia Jumes
- Clinical Pharmacology, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - John A. Wagner
- Clinical Pharmacology, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - David E. Gutstein
- Clinical Pharmacology, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Brian K. Hubbard
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Daniel J. Rader
- Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - John S. Millar
- Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - Michele Cleary
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | - Stephen F. Previs
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
- Correspondence to: S. F. Previs, Molecular Biomarkers, Merck Sharp & Dohme Corp., 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
| | - Thomas P. Roddy
- Molecular Biomarkers-PPDM, Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
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McLaren DG, Cardasis HL, Stout SJ, Wang SP, Mendoza V, Castro-Perez JM, Miller PL, Murphy BA, Cumiskey AM, Cleary MA, Johns DG, Previs SF, Roddy TP. Use of [13C18] oleic acid and mass isotopomer distribution analysis to study synthesis of plasma triglycerides in vivo: analytical and experimental considerations. Anal Chem 2013; 85:6287-94. [PMID: 23668715 DOI: 10.1021/ac400363k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have previously reported on a liquid chromatography-mass spectrometry method to determine the disposition of [(13)C18]-oleic acid following intravenous and oral administration in vivo. This approach has enabled us to study a variety of aspects of lipid metabolism including a quantitative assessment of triglyceride synthesis. Here we present a more rigorous evaluation of the constraints imposed upon the analytical method in order to generate accurate data using this stable-isotope tracer approach along with more detail on relevant analytical figures of merit including limits of quantitation, precision, and accuracy. The use of mass isotopomer distribution analysis (MIDA) to quantify plasma triglyceride synthesis is specifically highlighted, and a re-evaluation of the underlying mathematics has enabled us to present a simplified series of equations. The derivation of this MIDA model and the significance of all underlying assumptions are explored in detail, and examples are given of how it can successfully be applied to detect differences in plasma triglyceride synthesis in lean and high-fat diet fed mouse models. More work is necessary to evaluate the applicability of this approach to triglyceride stores with slower rates of turnover such as in adipose or muscle tissue; however, the present report provides investigators with the tools necessary to conduct such studies.
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Affiliation(s)
- David G McLaren
- Merck Research Laboratories, Merck & Co., Inc., Kenilworth, New Jersey 07033, USA.
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Previs SF, McLaren DG, Wang SP, Stout SJ, Zhou H, Herath K, Shah V, Miller PL, Wilsie L, Castro-Perez J, Johns DG, Cleary MA, Roddy TP. New methodologies for studying lipid synthesis and turnover: looking backwards to enable moving forwards. Biochim Biophys Acta Mol Basis Dis 2013; 1842:402-13. [PMID: 23707557 DOI: 10.1016/j.bbadis.2013.05.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/11/2013] [Accepted: 05/13/2013] [Indexed: 12/26/2022]
Abstract
Our ability to understand the pathogenesis of problems surrounding lipid accretion requires attention towards quantifying lipid kinetics. In addition, studies of metabolic flux should also help unravel mechanisms that lead to imbalances in inter-organ lipid trafficking which contribute to dyslipidemia and/or peripheral lipid accumulation (e.g. hepatic fat deposits). This review aims to outline the development and use of novel methods for studying lipid kinetics in vivo. Although our focus is directed towards some of the approaches that are currently reported in the literature, we include a discussion of the older literature in order to put "new" methods in better perspective and inform readers of valuable historical research. Presumably, future advances in understanding lipid dynamics will benefit from a careful consideration of the past efforts, where possible we have tried to identify seminal papers or those that provide clear data to emphasize essential points. This article is part of a Special Issue entitled: Modulation of Adipose Tissue in Health and Disease.
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Affiliation(s)
- Stephen F Previs
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
| | - David G McLaren
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Sheng-Ping Wang
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Steven J Stout
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Haihong Zhou
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Kithsiri Herath
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Vinit Shah
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Paul L Miller
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Larissa Wilsie
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Jose Castro-Perez
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Douglas G Johns
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Michele A Cleary
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
| | - Thomas P Roddy
- Molecular Biomarkers, Merck, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA
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Peier A, Wang SP, Krsmanovic M, Mendoza V, Shah V, Castro-Perez J, Roddy TP, Akinsanya K, Johns D. Abstract 119: LCAT Activation in Combination with the CETP Inhibitor Anacetrapib Results in Enhanced Cholesterol Efflux and a Favorable Lipid Profile in Dyslipidemic Hamsters. Arterioscler Thromb Vasc Biol 2013. [DOI: 10.1161/atvb.33.suppl_1.a119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Lecithin cholesterol acyltransferase (LCAT) is a key enzyme involved in the metabolism of HDL. LCAT synthesizes cholesterol esters (CE) in plasma by catalyzing the transfer of the sn-2 fatty acid of phosphatidylcholine to cholesterol on HDL. The hydrophobic CE moves to the core of the HDL particle which results in HDL maturation and a progressive enlargement of the particle. Cholesteryl ester transfer protein (CETP) is a plasma protein that facilitates the transport of CE from HDL to ApoB-containing lipoproteins. CETP inhibition has been identified as a potential strategy for lowering LDL-c and raising HDL cholesterol levels for the treatment of CVD.
The purpose of the current study was to test the hypothesis that CETP inhibition in the context of LCAT activation might yield an unfavorable lipoprotein profile (e.g. dysfunctional HDL). We measured plasma lipoprotein (via FPLC), particle size and
ex vivo
cholesterol efflux from dyslipidemic hamsters chronically treated with a small molecule LCAT activator (20 and 60 mpk/day) in the presence or absence of the CETP inhibitor anacetrapib (20mpk/day). As expected, anacetrapib significantly reduced LDL-c (-45%) and increased HDL-c (+63%) after chronic treatment. LCAT activation reduced TG (-35%) and increased HDL-c (+40-68%) but had no effect on LDL-c. Both treatments led to an apparent increase in HDL particle size as measured by FPLC. Additionally, LCAT activation showed a significant reduction in ABCA1-mediated efflux, presumably due to the resulting increase in HDL particle size. Animals that received both anacetrapib and the LCAT activator maintained the favorable lipid profile observed with single treatment. Moreover, HDL from hamsters treated with both LCATa and CETPi demonstrated a significant increase in ABCG1- and SRB1-mediated efflux whereas single treatment did not exhibit a measurable effect. We provide evidence that LCAT activation in the context of a CETP inhibitor, maintains a favorable lipid profile (lower LDL-c) and appear s to have a synergistic effect on cholesterol efflux.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Doug Johns
- Atherosclerosis, Merck Rsch Labs, Rahway, NJ
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McLaren DG, Wang SP, Stout SJ, Xie D, Miller PL, Mendoza V, Rosa R, Castro-Perez J, Previs SF, Johns DG, Roddy TP. Tracking fatty acid kinetics in distinct lipoprotein fractions in vivo: a novel high-throughput approach for studying dyslipidemia in rodent models. J Lipid Res 2012; 54:276-81. [PMID: 23042787 DOI: 10.1194/jlr.d030791] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Isotopic tracers have been used to examine lipid trafficking for many years, and data from those studies have typically yielded novel insight regarding the pathophysiology of dyslipidemia. Previous experimental designs were suitable for studies in humans because relatively large volumes of plasma could be regularly sampled. We have expanded on the earlier logic by applying high-throughput analytical methods that require reduced sample volumes. Specifically, we have examined the possibility of coupling gel-based separations of lipoproteins (e.g., lipoprint) with LC-MS/MS analyses of complex lipid mixtures as a way to routinely measure the labeling profiles of distinct lipids in discrete lipoprotein subfractions. We demonstrate the ability to measure the incorporation of [U-(13)C]oleate into triglycerides (TG), PLs (PL), and cholesterol esters (CE) in VLDL, LDL, and HDL particles in mice. Although rodent models of dyslipidemia are inherently different from humans because of alterations in enzyme activities and underlying metabolism, rodent models can be used to screen novel compounds for efficacy in altering a given biochemical pathway and therein enable studies of target engagement in vivo. We expect that it is possible to translate our approach for application in other systems, including studies in humans.
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38
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Chen Z, Wang SP, Krsmanovic ML, Castro-Perez J, Gagen K, Mendoza V, Rosa R, Shah V, He T, Stout SJ, Geoghagen NS, Lee SH, McLaren DG, Wang L, Roddy TP, Plump AS, Hubbard BK, Sinz CJ, Johns DG. Small molecule activation of lecithin cholesterol acyltransferase modulates lipoprotein metabolism in mice and hamsters. Metabolism 2012; 61:470-81. [PMID: 22001333 DOI: 10.1016/j.metabol.2011.08.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 08/10/2011] [Accepted: 08/18/2011] [Indexed: 11/20/2022]
Abstract
The objective was to assess whether pharmacological activation of lecithin cholesterol acyltransferase (LCAT) could exert beneficial effects on lipoprotein metabolism. A putative small molecule activator (compound A) was used as a tool compound in in vitro and in vivo studies. Compound A increased LCAT activity in vitro in plasma from mouse, hamster, rhesus monkey, and human. To assess the acute pharmacodynamic effects of compound A, C57Bl/6 mice and hamsters received a single dose (20 mg/kg) of compound A. Both species displayed a significant increase in high-density lipoprotein cholesterol (HDLc) and a significant decrease in non-HDLc and triglycerides acutely after dosing; these changes tracked with ex vivo plasma LCAT activity. To examine compound A's chronic effect on lipoprotein metabolism, hamsters received a daily dosing of vehicle or of 20 or 60 mg/kg of compound A for 2 weeks. At study termination, compound treatment resulted in a significant increase in HDLc, HDL particle size, plasma apolipoprotein A-I level, and plasma cholesteryl ester (CE) to free cholesterol ratio, and a significant reduction in very low-density lipoprotein cholesterol. The increase in plasma CE mirrored the increase in HDL CE. Triglycerides trended toward a dose-dependent decrease in very low-density lipoprotein and HDL, with multiple triglyceride species reaching statistical significance. Gallbladder bile acids content displayed a significant and more than 2-fold increase with the 60 mg/kg treatment. We characterized pharmacological activation of LCAT by a small molecule extensively for the first time, and our findings support the potential of this approach in treating dyslipidemia and atherosclerosis; our analyses also provide mechanistic insight on LCAT's role in lipoprotein metabolism.
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Affiliation(s)
- Zhu Chen
- Cardiovascular Diseases, Merck Research Laboratories, Rahway, NJ 07065, USA.
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Zhou H, Li W, Wang SP, Mendoza V, Rosa R, Hubert J, Herath K, McLaughlin T, Rohm RJ, Lassman ME, Wong KK, Johns DG, Previs SF, Hubbard BK, Roddy TP. Quantifying apoprotein synthesis in rodents: coupling LC-MS/MS analyses with the administration of labeled water. J Lipid Res 2012; 53:1223-31. [PMID: 22389331 DOI: 10.1194/jlr.d021295] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Stable isotope tracer studies of apoprotein flux in rodent models present difficulties as they require working with small volumes of plasma. We demonstrate the ability to measure apoprotein flux by administering either (2)H- or (18)O-labeled water to mice and then subjecting samples to LC-MS/MS analyses; we were able to simultaneously determine the labeling of several proteolytic peptides representing multiple apoproteins. Consistent with relative differences reported in the literature regarding apoprotein flux in humans, we found that the fractional synthetic rate of apoB is greater than apoA1 in mice. In addition, the method is suitable for quantifying acute changes in protein flux: we observed a stimulation of apoB production in mice following an intravenous injection of Intralipid and a decrease in apoB production in mice treated with an inhibitor of microsomal triglyceride transfer protein. In summary, we demonstrate a high-throughput method for studying apoprotein kinetics in rodent models. Although notable differences exist between lipoprotein profiles that are observed in rodents and humans, we expect that the method reported here has merit in studies of dyslipidemia as i) rodent models can be used to probe target engagement in cases where one aims to modulate apoprotein production and ii) the approach should be adaptable to studies in humans.
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Affiliation(s)
- Haihong Zhou
- Atherosclerosis, Merck Research Laboratories, Rahway, NJ 07065, USA
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Conway JP, Johns DG, Wang SP, Walker ND, McAvoy TA, Zhou H, Zhao X, Previs SF, Roddy TP, Hubbard BK, Yates NA, Hendrickson RC. Measuring H218O Tracer Incorporation on a QQQ-MS Platform Provides a Rapid, Transferable Screening Tool for Relative Protein Synthesis. J Proteome Res 2012; 11:1591-7. [DOI: 10.1021/pr2007494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- James P. Conway
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Douglas G. Johns
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Sheng-Ping Wang
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Nykia D. Walker
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Thomas A. McAvoy
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Haihong Zhou
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Xuemei Zhao
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Stephen F. Previs
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Thomas P. Roddy
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Brian K. Hubbard
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Nathan A. Yates
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
| | - Ronald C. Hendrickson
- Merck Research Laboratories, 126 East Lincoln Avenue, Rahway, New Jersey
07065, United States
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Lassman ME, McLaughlin TM, Somers EP, Stefanni AC, Chen Z, Murphy BA, Bierilo KK, Flattery AM, Wong KK, Castro-Perez JM, Hubbard BK, Roddy TP. A rapid method for cross-species quantitation of apolipoproteins A1, B48 and B100 in plasma by ultra-performance liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Spectrom 2012; 26:101-108. [PMID: 22173797 DOI: 10.1002/rcm.5296] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Apolipoprotein B100 (apoB100) and apolipoprotein A1 (apoA1) are the primary protein components of low density lipoprotein (LDL) and high density lipoprotein (HDL) particles, respectively, and plasma levels of these proteins are associated with risks of cardiovascular disease. Existing apoB100 quantitation methods for animal models have been limited to affinity capture techniques such as enzyme-linked immunosorbent assay (ELISA) and Western blot which require specialized reagents for each species and in many cases are not readily available. Here we demonstrate a single translatable ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) assay that is fast and robust and can be used to measure apolipoprotein concentrations in plasma for six species. When possible, peptide sequences that are conserved across species were identified for this assay. The sample preparation is limited and can be carried out in 96-well microtiter plates and thus allows for multiplexed preparation of samples for analysis of large numbers of samples in a short time frame when combined with UPLC/MS/MS. Separation and quantitation of the tryptic peptides is carried out at 700 μL/min using a 1.7 µm core shell C18 column (2.1 × 50 mm). The chromatography is designed for the analysis of over 100 samples per day, and the UPLC run is less than 10 min. This assay is capable of supporting cardiovascular research by providing a single assay to measure critical biomarkers across multiple species without the need for antibodies, and does so in a high-throughput manner.
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Affiliation(s)
- Michael E Lassman
- Merck Research Laboratories, 126 E. Lincoln Ave., Rahway, NJ 07065, USA.
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Jensen KK, Previs SF, Zhu L, Herath K, Wang SP, Bhat G, Hu G, Miller PL, McLaren DG, Shin MK, Vogt TF, Wang L, Wong KK, Roddy TP, Johns DG, Hubbard BK. Demonstration of diet-induced decoupling of fatty acid and cholesterol synthesis by combining gene expression array and 2H2O quantification. Am J Physiol Endocrinol Metab 2012; 302:E209-17. [PMID: 22045313 DOI: 10.1152/ajpendo.00436.2011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The liver is a crossroad for metabolism of lipid and carbohydrates, with acetyl-CoA serving as an important metabolic intermediate and a precursor for fatty acid and cholesterol biosynthesis pathways. A better understanding of the regulation of these pathways requires an experimental approach that provides both quantitative metabolic flux measurements and mechanistic insight. Under conditions of high carbohydrate availability, excess carbon is converted into free fatty acids and triglyceride for storage, but it is not clear how excessive carbohydrate availability affects cholesterol biosynthesis. To address this, C57BL/6J mice were fed either a low-fat, high-carbohydrate diet or a high-fat, carbohydrate-free diet. At the end of the dietary intervention, the two groups received (2)H(2)O to trace de novo fatty acid and cholesterol synthesis, and livers were collected for gene expression analysis. Expression of lipid and glucose metabolism genes was determined using a custom-designed pathway focused PCR-based gene expression array. The expression analysis showed downregulation of cholesterol biosynthesis genes and upregulation of fatty acid synthesis genes in mice receiving the high-carbohydrate diet compared with the carbohydrate-free diet. In support of these findings, (2)H(2)O tracer data showed that fatty acid synthesis was increased 10-fold and cholesterol synthesis was reduced by 1.6-fold in mice fed the respective diets. In conclusion, by applying gene expression analysis and tracer methodology, we show that fatty acid and cholesterol synthesis are differentially regulated when the carbohydrate intake in mice is altered.
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Affiliation(s)
- Kristian K Jensen
- Department of Atherosclerosis, Merck Research Labs., Merck & Co., Inc., 126 E. Lincoln Ave., Rahway, NJ 07065, USA.
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43
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Han S, Flattery AM, McLaren D, Raubertas R, Lee SH, Mendoza V, Rosa R, Geoghagen N, Castro-Perez JM, Roddy TP, Forrest G, Johns D, Hubbard BK, Li J. Comparison of lipoprotein separation and lipid analysis methodologies for human and cynomolgus monkey plasma samples. J Cardiovasc Transl Res 2011; 5:75-83. [PMID: 22194019 DOI: 10.1007/s12265-011-9340-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 12/08/2011] [Indexed: 11/30/2022]
Abstract
To assess cardiovascular risk in both clinical and basic research settings, it is imperative to be able to accurately measure plasma lipid levels. Here, methods commonly used to measure lipoproteins and lipids: ultracentrifugation (UC), fast protein liquid chromatography (FPLC), Roche auto-analyzer, and enzymatic assays were tested and compared. Plasma samples from 20 healthy humans and 22 cynomolgus monkeys were analyzed for their total cholesterol (TC), cholesterol in low density lipoproteins (LDL) and high density lipoproteins (HDL), and triglycerides (TG). Major lipid classes from UC and FPLC separated lipoprotein fractions from human plasma were further characterized by liquid chromatography-mass spectrometry analysis. All the tested methods showed acceptable performance with Roche analyzer among the best in approximate dilution linearity and recovery for most lipids as well as in repeatability between measurements of the same samples. TC, LDL, HDL, and TG values measured in human vs. monkey were-183.9 ± 35.5 (mean ± SD) vs. 105.6 ± 24.6 mg/dl, 106.0 ± 30.1 vs. 42.8 ± 13.0 mg/dl, 50.0 ± 11.4 vs. 53.4 ± 14.8 mg/dl, and 107.6 ± 50.7 vs. 58.0 ± 52.3 mg/dl. While no single method was uniformly the best, we recommend the Roche analyzer for routine measurements. UC or FPLC separation is needed for further functional characterization for specific lipid fraction. We have shown athero-protective profile in cynomolgus monkey compared with humans.
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Affiliation(s)
- Seongah Han
- Division of Cardiovascular Disease, Merck Research Laboratories, Rahway, NJ 07065, USA.
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Castro-Perez J, Briand F, Gagen K, Wang SP, Chen Y, McLaren DG, Shah V, Vreeken RJ, Hankemeier T, Sulpice T, Roddy TP, Hubbard BK, Johns DG. Anacetrapib promotes reverse cholesterol transport and bulk cholesterol excretion in Syrian golden hamsters. J Lipid Res 2011; 52:1965-73. [PMID: 21841206 PMCID: PMC3196228 DOI: 10.1194/jlr.m016410] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 07/29/2011] [Indexed: 11/20/2022] Open
Abstract
Cholesteryl ester transfer protein (CETP) transfers cholesteryl ester (CE) and triglyceride between HDL and apoB-containing lipoproteins. Anacetrapib (ANA), a reversible inhibitor of CETP, raises HDL cholesterol (HDL-C) and lowers LDL cholesterol in dyslipidemic patients; however, the effects of ANA on cholesterol/lipoprotein metabolism in a dyslipidemic hamster model have not been demonstrated. To test whether ANA (60 mg/kg/day, 2 weeks) promoted reverse cholesterol transport (RCT), ³H-cholesterol-loaded macrophages were injected and (3)H-tracer levels were measured in HDL, liver, and feces. Compared to controls, ANA inhibited CETP (94%) and increased HDL-C (47%). ³H-tracer in HDL increased by 69% in hamsters treated with ANA, suggesting increased cholesterol efflux from macrophages to HDL. ³H-tracer in fecal cholesterol and bile acids increased by 90% and 57%, respectively, indicating increased macrophage-to-feces RCT. Mass spectrometry analysis of HDL from ANA-treated hamsters revealed an increase in free unlabeled cholesterol and CE. Furthermore, bulk cholesterol and cholic acid were increased in feces from ANA-treated hamsters. Using two independent approaches to assess cholesterol metabolism, the current study demonstrates that CETP inhibition with ANA promotes macrophage-to-feces RCT and results in increased fecal cholesterol/bile acid excretion, further supporting its development as a novel lipid therapy for the treatment of dyslipidemia and atherosclerotic vascular disease.
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Affiliation(s)
- Jose Castro-Perez
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
- Division of Analytical Biosciences, Netherlands Metabolomics Centre, Leiden, The Netherlands
| | - François Briand
- Physiogenex, Prologue Biotech, Labege-Innopole cedex, France
| | - Karen Gagen
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - Sheng-Ping Wang
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - Ying Chen
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - David G. McLaren
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - Vinit Shah
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - Rob J. Vreeken
- Division of Analytical Biosciences, Netherlands Metabolomics Centre, Leiden, The Netherlands
- LACDR, Leiden University, Leiden, The Netherlands
| | - Thomas Hankemeier
- Division of Analytical Biosciences, Netherlands Metabolomics Centre, Leiden, The Netherlands
- LACDR, Leiden University, Leiden, The Netherlands
| | - Thierry Sulpice
- Physiogenex, Prologue Biotech, Labege-Innopole cedex, France
| | - Thomas P. Roddy
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - Brian K. Hubbard
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
| | - Douglas G. Johns
- Department of Cardiovascular Diseases, Atherosclerosis, Merck Research Laboratories, Rahway, NJ
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Yin W, Carballo-Jane E, McLaren DG, Mendoza VH, Gagen K, Geoghagen NS, McNamara LA, Gorski JN, Eiermann GJ, Petrov A, Wolff M, Tong X, Wilsie LC, Akiyama TE, Chen J, Thankappan A, Xue J, Ping X, Andrews G, Wickham LA, Gai CL, Trinh T, Kulick AA, Donnelly MJ, Voronin GO, Rosa R, Cumiskey AM, Bekkari K, Mitnaul LJ, Puig O, Chen F, Raubertas R, Wong PH, Hansen BC, Koblan KS, Roddy TP, Hubbard BK, Strack AM. Plasma lipid profiling across species for the identification of optimal animal models of human dyslipidemia. J Lipid Res 2011; 53:51-65. [PMID: 22021650 DOI: 10.1194/jlr.m019927] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In an attempt to understand the applicability of various animal models to dyslipidemia in humans and to identify improved preclinical models for target discovery and validation for dyslipidemia, we measured comprehensive plasma lipid profiles in 24 models. These included five mouse strains, six other nonprimate species, and four nonhuman primate (NHP) species, and both healthy animals and animals with metabolic disorders. Dyslipidemic humans were assessed by the same measures. Plasma lipoprotein profiles, eight major plasma lipid fractions, and FA compositions within these lipid fractions were compared both qualitatively and quantitatively across the species. Given the importance of statins in decreasing plasma low-density lipoprotein cholesterol for treatment of dyslipidemia in humans, the responses of these measures to simvastatin treatment were also assessed for each species and compared with dyslipidemic humans. NHPs, followed by dog, were the models that demonstrated closest overall match to dyslipidemic humans. For the subset of the dyslipidemic population with high plasma triglyceride levels, the data also pointed to hamster and db/db mouse as representative models for practical use in target validation. Most traditional models, including rabbit, Zucker diabetic fatty rat, and the majority of mouse models, did not demonstrate overall similarity to dyslipidemic humans in this study.
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Affiliation(s)
- Wu Yin
- Department of Atherosclerosis, Merck Research Laboratories, Rahway, NJ 07065, USA
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Castro-Perez J, Roddy TP, Nibbering NMM, Shah V, McLaren DG, Previs S, Attygalle AB, Herath K, Chen Z, Wang SP, Mitnaul L, Hubbard BK, Vreeken RJ, Johns DG, Hankemeier T. Localization of fatty acyl and double bond positions in phosphatidylcholines using a dual stage CID fragmentation coupled with ion mobility mass spectrometry. J Am Soc Mass Spectrom 2011; 22:1552-67. [PMID: 21953258 PMCID: PMC3158848 DOI: 10.1007/s13361-011-0172-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2011] [Revised: 05/15/2011] [Accepted: 05/17/2011] [Indexed: 05/03/2023]
Abstract
A high content molecular fragmentation for the analysis of phosphatidylcholines (PC) was achieved utilizing a two-stage [trap (first generation fragmentation) and transfer (second generation fragmentation)] collision-induced dissociation (CID) in combination with travelling-wave ion mobility spectrometry (TWIMS). The novel aspects of this work reside in the fact that a TWIMS arrangement was used to obtain a high level structural information including location of fatty acyl substituents and double bonds for PCs in plasma, and the presence of alkali metal adduct ions such as [M + Li](+) was not required to obtain double bond positions. Elemental compositions for fragment ions were confirmed by accurate mass measurements. A very specific first generation fragment ion m/z 577 (M-phosphoryl choline) from the PC [16:0/18:1 (9Z)] was produced, which by further CID generated acylium ions containing either the fatty acyl 16:0 (C(15)H(31)CO(+), m/z 239) or 18:1 (9Z) (C(17)H(33)CO(+), m/z 265) substituent. Subsequent water loss from these acylium ions was key in producing hydrocarbon fragment ions mainly from the α-proximal position of the carbonyl group such as the hydrocarbon ion m/z 67 (+H(2)C-HC = CH-CH = CH(2)). Formation of these ions was of important significance for determining double bonds in the fatty acyl chains. In addition to this, and with the aid of (13)C labeled lyso-phosphatidylcholine (LPC) 18:1 (9Z) in the ω-position (methyl) TAP fragmentation produced the ion at m/z 57. And was proven to be derived from the α-proximal (carboxylate) or distant ω-position (methyl) in the LPC.
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Affiliation(s)
- Jose Castro-Perez
- Department of Atherosclerosis Exploratory Biomarkers, Merck Research Laboratories, 126 E. Lincoln Ave, 80Y-2D7, Rahway, NJ 07065, USA.
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47
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Castro-Perez JM, Roddy TP, Shah V, Wang SP, Ouyang X, Ogawa A, McLaren DG, Tadin-Strapps M, Robinson MJ, Bartz SR, Ason B, Chen Y, Previs SF, Wong KK, Vreeken RJ, Johns DG, Hubbard BK, Hankemeier T, Mitnaul L. Attenuation of Slc27a5 gene expression followed by LC-MS measurement of bile acid reconjugation using metabolomics and a stable isotope tracer strategy. J Proteome Res 2011; 10:4683-91. [PMID: 21819150 DOI: 10.1021/pr200475g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The purpose of this study was to evaluate the use of high resolution LC-MS together with metabolomics and D(4)-cholic acid (D(4)-CA) as a metabolic tracer to measure the metabolism and reconjugation of bile acids (BAs) in vitro and in vivo. Metabolic tracers are very important because they allow for the direct detection (substrate-to-product) of small and significant biological perturbations that may not be apparent when monitoring "static" endogenous levels of particular metabolites. Slc27a5, also known as fatty acid transport protein 5 (FATP5), is the hepatic BA-CoA ligase involved in reconjugating BAs during enterohepatic BA recycling. Using Slc27a5-cKD mice, silencing of ∼90% gene expression was achieved followed by reduction in the reconjugation of D(4)-CA to D(4)-taurocholic acid (D(4)-TCA), as well as other conjugated BA metabolites in plasma (p = 0.0031). The method described allowed a rapid measure of many D(4) and endogenous BA. Analysis of bile resulted in the detection of 39 BA metabolites from a 13 min analytical run. Finally, the utilization of a novel high resolution mass spectrometry method in combination with metabolomics and a stable isotope metabolic tracer allowed for the detection of targeted and untargeted BAs following silencing of the Slc27a5 gene in primary hepatocytes and in mice.
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48
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Castro-Perez JM, Roddy TP, Shah V, McLaren DG, Wang SP, Jensen K, Vreeken RJ, Hankemeier T, Johns DG, Previs SF, Hubbard BK. Identifying Static and Kinetic Lipid Phenotypes by High Resolution UPLC–MS: Unraveling Diet-Induced Changes in Lipid Homeostasis by Coupling Metabolomics and Fluxomics. J Proteome Res 2011; 10:4281-90. [DOI: 10.1021/pr200480g] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jose M. Castro-Perez
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
- Division of Analytical Biosciences, LACDR, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Thomas P. Roddy
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - Vinit Shah
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - David G. McLaren
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - Sheng-Ping Wang
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - Kristian Jensen
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - Rob J. Vreeken
- Division of Analytical Biosciences, LACDR, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
- Netherlands Metabolomics Centre, LACDR, Leiden University, P.O. Box 9502, 2300RA Leiden, The Netherlands
| | - Thomas Hankemeier
- Division of Analytical Biosciences, LACDR, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
- Netherlands Metabolomics Centre, LACDR, Leiden University, P.O. Box 9502, 2300RA Leiden, The Netherlands
| | - Douglas G. Johns
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - Stephen F. Previs
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
| | - Brian K. Hubbard
- Department of Cardiovascular Diseases − Atherosclerosis Rahway, Merck Research Laboratories, New Jersey 07065, United States
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Herath K, Bhat G, Miller PL, Wang SP, Kulick A, Andrews-Kelly G, Johnson C, Rohm RJ, Lassman ME, Previs SF, Johns DG, Hubbard BK, Roddy TP. Equilibration of (2)H labeling between body water and free amino acids: enabling studies of proteome synthesis. Anal Biochem 2011; 415:197-9. [PMID: 21596013 DOI: 10.1016/j.ab.2011.04.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Revised: 04/02/2011] [Accepted: 04/19/2011] [Indexed: 11/19/2022]
Abstract
Protein synthesis can be estimated by measuring the incorporation of a labeled amino acid into a proteolytic peptide. Although prelabeled amino acids are typically administered, recent studies have tested (2)H(2)O; the assumption is that there is rapid equilibration of (2)H (in body water) with the carbon-bound hydrogens of amino acids before those amino acids are incorporated into a protein(s). We have determined the temporal changes in (2)H labeling of body water and amino acids which should build confidence in (2)H(2)O-based studies of protein synthesis when one aims to measure the (2)H labeling of proteolytic peptides.
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Affiliation(s)
- Kithsiri Herath
- Atherosclerosis, Merck Research Laboratories, Rahway, NJ 07065, USA
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Previs SF, Mahsut A, Kulick A, Dunn K, Andrews-Kelly G, Johnson C, Bhat G, Herath K, Miller PL, Wang SP, Azer K, Xu J, Johns DG, Hubbard BK, Roddy TP. Quantifying cholesterol synthesis in vivo using (2)H(2)O: enabling back-to-back studies in the same subject. J Lipid Res 2011; 52:1420-8. [PMID: 21498887 DOI: 10.1194/jlr.d014993] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The advantages of using (2)H(2)O to quantify cholesterol synthesis include i) homogeneous precursor labeling, ii) incorporation of (2)H via multiple pathways, and iii) the ability to perform long-term studies in free-living subjects. However, there are two concerns. First, the t(1/2) of tracer in body water presents a challenge when there is a need to acutely replicate measurements in the same subject. Second, assumptions are made regarding the number of hydrogens (n) that are incorporated during de novo synthesis. Our primary objective was to determine whether a step-based approach could be used to repeatedly study cholesterol synthesis a subject. We observed comparable changes in the (2)H-labeling of plasma water and total plasma cholesterol in African-Green monkeys that received five oral doses of (2)H(2)O, each dose separated by one week. Similar rates of cholesterol synthesis were estimated when comparing data in the group over the different weeks, but better reproducibility was observed when comparing replicate determinations of cholesterol synthesis in the same nonhuman primate during the respective dosing periods. Our secondary objective was to determine whether n depends on nutritional status in vivo; we observed n of ∼25 and ∼27 in mice fed a high-carbohydrate (HC) versus carbohydrate-free (CF) diet, respectively. We conclude that it is possible to acutely repeat studies of cholesterol synthesis using (2)H(2)O and that n is relatively constant.
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