Rewiring of Glutamine Metabolism Is a Bioenergetic Adaptation of Human Cells with Mitochondrial DNA Mutations

Qiuying Chen, Kathryne Kirk, Yevgeniya I. Shurubor, Dazhi Zhao, Andrea J. Arreguin, Ifrah Shahi, Federica Valsecchi, Guido Primiano, Elizabeth L. Calder, Valerio Carelli, Travis T. Denton, M. Flint Beal, Steven S. Gross, Giovanni Manfredi, Marilena D'Aurelio

Research output: Contribution to journalArticle

Abstract

Using molecular, biochemical, and untargeted stable isotope tracing approaches, we identify a previously unappreciated glutamine-derived α-ketoglutarate (αKG) energy-generating anaplerotic flux to be critical in mitochondrial DNA (mtDNA) mutant cells that harbor human disease-associated oxidative phosphorylation defects. Stimulating this flux with αKG supplementation enables the survival of diverse mtDNA mutant cells under otherwise lethal obligatory oxidative conditions. Strikingly, we demonstrate that when residual mitochondrial respiration in mtDNA mutant cells exceeds 45% of control levels, αKG oxidative flux prevails over reductive carboxylation. Furthermore, in a mouse model of mitochondrial myopathy, we show that increased oxidative αKG flux in muscle arises from enhanced alanine synthesis and release into blood, concomitant with accelerated amino acid catabolism from protein breakdown. Importantly, in this mouse model of mitochondriopathy, muscle amino acid imbalance is normalized by αKG supplementation. Taken together, our findings provide a rationale for αKG supplementation as a therapeutic strategy for mitochondrial myopathies. Chen et al. show that patient cells with mtDNA mutations and a mouse model of mitochondrial myopathy have compensatory glutamine-derived anaplerotic flux that provides αKG to the TCA cycle to enable mutant cell survival. The metabolic fate of αKG (oxidative versus reductive) depends on the severity of OXPHOS impairment.

Original languageEnglish
Pages (from-to)1007-1025.e5
JournalCell Metabolism
Volume27
Issue number5
DOIs
Publication statusPublished - May 1 2018

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Keywords

  • anaplerosis
  • glutamate
  • glutamine
  • metabolism
  • mitochondria
  • mitochondrial diseases
  • myopathy
  • OXPHOS dysfunction
  • skeletal muscle
  • α-ketoglutarate

ASJC Scopus subject areas

  • Physiology
  • Molecular Biology
  • Cell Biology

Cite this

Chen, Q., Kirk, K., Shurubor, Y. I., Zhao, D., Arreguin, A. J., Shahi, I., Valsecchi, F., Primiano, G., Calder, E. L., Carelli, V., Denton, T. T., Beal, M. F., Gross, S. S., Manfredi, G., & D'Aurelio, M. (2018). Rewiring of Glutamine Metabolism Is a Bioenergetic Adaptation of Human Cells with Mitochondrial DNA Mutations. Cell Metabolism, 27(5), 1007-1025.e5. https://doi.org/10.1016/j.cmet.2018.03.002