Etomoxir Inhibits Macrophage Polarization by Disrupting CoA Homeostasis

Ajit S Divakaruni; Wei Yuan Hsieh; Lucía Minarrieta; Tin N Duong; Kristen K O Kim; Brandon R Desousa; Alexander Y Andreyev; Caitlyn E Bowman; Kacey Caradonna; Brian P Dranka; David A Ferrick; Marc Liesa; Linsey Stiles; George W Rogers; Daniel Braas; Theodore P Ciaraldi; Michael J Wolfgang; Tim Sparwasser; Luciana Berod; Steven J Bensinger; Anne N Murphy

doi:10.1016/j.cmet.2018.06.001

Etomoxir Inhibits Macrophage Polarization by Disrupting CoA Homeostasis

Cell Metab. 2018 Sep 4;28(3):490-503.e7. doi: 10.1016/j.cmet.2018.06.001. Epub 2018 Jun 28.

Authors

Ajit S Divakaruni¹, Wei Yuan Hsieh², Lucía Minarrieta³, Tin N Duong², Kristen K O Kim⁴, Brandon R Desousa⁴, Alexander Y Andreyev⁵, Caitlyn E Bowman⁶, Kacey Caradonna⁷, Brian P Dranka⁷, David A Ferrick⁷, Marc Liesa⁸, Linsey Stiles⁸, George W Rogers⁷, Daniel Braas⁹, Theodore P Ciaraldi¹⁰, Michael J Wolfgang⁶, Tim Sparwasser³, Luciana Berod³, Steven J Bensinger¹¹, Anne N Murphy⁵

Affiliations

¹ Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA. Electronic address: adivakaruni@mednet.ucla.edu.
² Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
³ Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, A Joint Venture Between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Hannover, Germany.
⁴ Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
⁵ Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA.
⁶ Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
⁷ Agilent Technologies, 5301 Stevens Creek Boulevard, Santa Clara, CA 95051, USA.
⁸ Department of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
⁹ Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA; UCLA Metabolomics Center and Crump Institute for Molecular Imaging, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
¹⁰ Veterans Affairs San Diego Healthcare System, La Jolla, CA 92161, USA; Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
¹¹ Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.

Abstract

Long-chain fatty acid (LCFA) oxidation has been shown to play an important role in interleukin-4 (IL-4)-mediated macrophage polarization (M(IL-4)). However, many of these conclusions are based on the inhibition of carnitine palmitoyltransferase-1 with high concentrations of etomoxir that far exceed what is required to inhibit enzyme activity (EC₉₀ < 3 μM). We employ genetic and pharmacologic models to demonstrate that LCFA oxidation is largely dispensable for IL-4-driven polarization. Unexpectedly, high concentrations of etomoxir retained the ability to disrupt M(IL-4) polarization in the absence of Cpt1a or Cpt2 expression. Although excess etomoxir inhibits the adenine nucleotide translocase, oxidative phosphorylation is surprisingly dispensable for M(IL-4). Instead, the block in polarization was traced to depletion of intracellular free coenzyme A (CoA), likely resulting from conversion of the pro-drug etomoxir into active etomoxiryl CoA. These studies help explain the effect(s) of excess etomoxir on immune cells and reveal an unappreciated role for CoA metabolism in macrophage polarization.

Keywords: CPT-1; CPT-2; coenzyme A; interleukin 4; long-chain fatty acid oxidation; macrophage polarization; mitochondria; oxidative phosphorylation; pantothenate.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

3T3 Cells
A549 Cells
Acyl Coenzyme A / physiology*
Animals
Carnitine O-Palmitoyltransferase / metabolism
Enzyme Inhibitors / pharmacology*
Epoxy Compounds / pharmacology*
Fatty Acids / metabolism
HCT116 Cells
Hep G2 Cells
Homeostasis / drug effects*
Humans
Interleukin-4 / metabolism
Liver / metabolism
Macrophage Activation / drug effects
Macrophages* / drug effects
Macrophages* / metabolism
Male
Mice
Mice, Inbred C57BL
Mitochondria* / drug effects
Mitochondria* / metabolism
Mitochondrial ADP, ATP Translocases / metabolism
Oxidative Phosphorylation / drug effects
Rats
Rats, Sprague-Dawley

Substances

Acyl Coenzyme A
Enzyme Inhibitors
Epoxy Compounds
Fatty Acids
etomoxiryl-coenzyme A
Interleukin-4
Mitochondrial ADP, ATP Translocases
CPT1B protein, mouse
Carnitine O-Palmitoyltransferase
etomoxir

Abstract

Publication types

MeSH terms

Substances

Grants and funding