Flux Through Hepatic Pyruvate Carboxylase and Phosphoenolpyruvate Carboxykinase Detected by Hyperpolarized 13C Magnetic Resonance

Overview

Journal Proc Natl Acad Sci U S A

Specialty Science

Date 2011 Nov 9

PMID 22065779

Citations 79

Authors

Matthew E Merritt

Crystal Harrison

A Dean Sherry

Craig R Malloy

Shawn C Burgess

Affiliations

Soon will be listed here.

Abstract

In the heart, detection of hyperpolarized [(13)C]bicarbonate and (13)CO(2) by magnetic resonance (MR) after administration of hyperpolarized [1-(13)C]pyruvate is caused exclusively by oxidative decarboxylation of pyruvate via the pyruvate dehydrogenase complex (PDH). However, liver mitochondria possess alternative anabolic pathways accessible by [1-(13)C]pyruvate, which may allow a wider diagnostic range for hyperpolarized MR compared with other tissue. Metabolism of hyperpolarized [1-(13)C]pyruvate in the tricarboxylic acid (TCA) cycle was monitored in the isolated perfused liver from fed and fasted mice. Hyperpolarized [1-(13)C]pyruvate was rapidly converted to [1-(13)C]lactate, [1-(13)C]alanine, [1-(13)C]malate, [4-(13)C]malate, [1-(13)C]aspartate, [4-(13)C]aspartate, and [(13)C]bicarbonate. Livers from fasted animals had increased lactate:alanine, consistent with elevated NADH:NAD(+). The appearance of asymmetrically enriched malate and aspartate indicated high rates of anaplerotic pyruvate carboxylase activity and incomplete equilibration with fumarate. Hyperpolarized [(13)C]bicarbonate was also detected, consistent with multiple mechanisms, including cataplerotic decarboxylation of [4-(13)C]oxaloacetate via phosphoenolpyruvate carboxykinase (PEPCK), forward TCA cycle flux of [4-(13)C]oxaloacetate to generate (13)CO(2) at isocitrate dehydrogenase, or decarboxylation of [1-(13)C]pyruvate by PDH. Isotopomer analysis of liver glutamate confirmed that anaplerosis was sevenfold greater than flux through PDH. In addition, signal from [4-(13)C]malate and [4-(13)C]aspartate was markedly blunted and signal from [(13)C]bicarbonate was completely abolished in livers from PEPCK KO mice, indicating that the major pathway for entry of hyperpolarized [1-(13)C]pyruvate into the hepatic TCA cycle is via pyruvate carboxylase, and that cataplerotic flux through PEPCK is the primary source of [(13)C]bicarbonate. We conclude that MR detection of hyperpolarized TCA intermediates and bicarbonate is diagnostic of pyruvate carboxylase and PEPCK flux in the liver.

Citing Articles

The mitochondrial dicarboxylate carrier mediates in vivo hepatic gluconeogenesis.

Pape D, Falls-Hubert K, Merrill R, Ahmed A, Qian Q, McGivney G bioRxiv. 2024; .

PMID: 39314408 PMC: 11419125. DOI: 10.1101/2024.09.12.612761.

Hyperpolarized [2-C, 3-H]Pyruvate Detects Hepatic Gluconeogenesis .

Huynh M, Erfani Z, Kovacs Z, Park J ACS Sens. 2024; 9(6):2801-2805.

PMID: 38838349 PMC: 11227886. DOI: 10.1021/acssensors.4c00734.

Toward Ultra-High-Quality-Factor Wireless Masing Magnetic Resonance Sensing.

Adelabu I, Nantogma S, Fleischer S, Abdulmojeed M, de Maissin H, Schmidt A Angew Chem Int Ed Engl. 2024; 63(37):e202406551.

PMID: 38822492 PMC: 11463167. DOI: 10.1002/anie.202406551.

Effects of hepatic mitochondrial pyruvate carrier deficiency on lipogenesis and gluconeogenesis in mice.

Yiew N, Deja S, Ferguson D, Cho K, Jarasvaraparn C, Jacome-Sosa M iScience. 2023; 26(11):108196.

PMID: 37942005 PMC: 10628847. DOI: 10.1016/j.isci.2023.108196.

Observing exocrine pancreas metabolism using a novel pancreas perfusion technique in combination with hyperpolarized [1- C]pyruvate.

Rushin A, McLeod M, Ragavan M, Merritt M Magn Reson Chem. 2023; 61(12):748-758.

PMID: 37482899 PMC: 10800648. DOI: 10.1002/mrc.5382.

References

Chen A, Albers M, Cunningham C, Kohler S, Yen Y, Hurd R . Hyperpolarized C-13 spectroscopic imaging of the TRAMP mouse at 3T-initial experience. Magn Reson Med. 2007; 58(6):1099-106. DOI: 10.1002/mrm.21256. View

Jones J, Naidoo R, Sherry A, Jeffrey F, Cottam G, Malloy C . Measurement of gluconeogenesis and pyruvate recycling in the rat liver: a simple analysis of glucose and glutamate isotopomers during metabolism of [1,2,3-(13)C3]propionate. FEBS Lett. 1997; 412(1):131-7. DOI: 10.1016/s0014-5793(97)00764-3. View

Williamson D, Lund P, KREBS H . The redox state of free nicotinamide-adenine dinucleotide in the cytoplasm and mitochondria of rat liver. Biochem J. 1967; 103(2):514-27. PMC: 1270436. DOI: 10.1042/bj1030514. View

Yang J, Shen J . Relayed (13)C magnetization transfer: detection of malate dehydrogenase reaction in vivo. J Magn Reson. 2006; 184(2):344-9. PMC: 2800356. DOI: 10.1016/j.jmr.2006.11.002. View

Cohen S . 13C NMR study of effects of fasting and diabetes on the metabolism of pyruvate in the tricarboxylic acid cycle and the utilization of pyruvate and ethanol in lipogenesis in perfused rat liver. Biochemistry. 1987; 26(2):581-9. DOI: 10.1021/bi00376a033. View

Malloy C, Sherry A, Jeffrey F . Analysis of tricarboxylic acid cycle of the heart using 13C isotope isomers. Am J Physiol. 1990; 259(3 Pt 2):H987-95. DOI: 10.1152/ajpheart.1990.259.3.H987. View

Burgess S, Hausler N, Merritt M, Jeffrey F, Storey C, Milde A . Impaired tricarboxylic acid cycle activity in mouse livers lacking cytosolic phosphoenolpyruvate carboxykinase. J Biol Chem. 2004; 279(47):48941-9. DOI: 10.1074/jbc.M407120200. View

Spielman D, Mayer D, Yen Y, Tropp J, Hurd R, Pfefferbaum A . In vivo measurement of ethanol metabolism in the rat liver using magnetic resonance spectroscopy of hyperpolarized [1-13C]pyruvate. Magn Reson Med. 2009; 62(2):307-13. PMC: 2780439. DOI: 10.1002/mrm.21998. View

Hausler N, Browning J, Merritt M, Storey C, Milde A, Jeffrey F . Effects of insulin and cytosolic redox state on glucose production pathways in the isolated perfused mouse liver measured by integrated 2H and 13C NMR. Biochem J. 2005; 394(Pt 2):465-73. PMC: 1408677. DOI: 10.1042/BJ20051174. View

10.

Chen A, Tropp J, Hurd R, van Criekinge M, Carvajal L, Xu D . In vivo hyperpolarized 13C MR spectroscopic imaging with 1H decoupling. J Magn Reson. 2008; 197(1):100-6. PMC: 2745403. DOI: 10.1016/j.jmr.2008.12.004. View

11.

Rothman D, Magnusson I, Katz L, Shulman R, Shulman G . Quantitation of hepatic glycogenolysis and gluconeogenesis in fasting humans with 13C NMR. Science. 1991; 254(5031):573-6. DOI: 10.1126/science.1948033. View

12.

She P, Shiota M, Shelton K, Chalkley R, Postic C, Magnuson M . Phosphoenolpyruvate carboxykinase is necessary for the integration of hepatic energy metabolism. Mol Cell Biol. 2000; 20(17):6508-17. PMC: 86125. DOI: 10.1128/MCB.20.17.6508-6517.2000. View

13.

Schroeder M, Atherton H, Ball D, Cole M, Heather L, Griffin J . Real-time assessment of Krebs cycle metabolism using hyperpolarized 13C magnetic resonance spectroscopy. FASEB J. 2009; 23(8):2529-38. PMC: 2717776. DOI: 10.1096/fj.09-129171. View

14.

Lau A, Chen A, Ghugre N, Ramanan V, Lam W, Connelly K . Rapid multislice imaging of hyperpolarized 13C pyruvate and bicarbonate in the heart. Magn Reson Med. 2010; 64(5):1323-31. DOI: 10.1002/mrm.22525. View

15.

Magnusson I, Schumann W, BARTSCH G, Chandramouli V, Kumaran K, Wahren J . Noninvasive tracing of Krebs cycle metabolism in liver. J Biol Chem. 1991; 266(11):6975-84. View

16.

Ardenkjaer-Larsen J, Fridlund B, Gram A, Hansson G, Hansson L, Lerche M . Increase in signal-to-noise ratio of > 10,000 times in liquid-state NMR. Proc Natl Acad Sci U S A. 2003; 100(18):10158-63. PMC: 193532. DOI: 10.1073/pnas.1733835100. View

17.

Jeffrey F, Storey C, Sherry A, Malloy C . 13C isotopomer model for estimation of anaplerotic substrate oxidation via acetyl-CoA. Am J Physiol. 1996; 271(4 Pt 1):E788-99. DOI: 10.1152/ajpendo.1996.271.4.E788. View

18.

Gallagher F, Kettunen M, Hu D, Jensen P, In t Zandt R, Karlsson M . Production of hyperpolarized [1,4-13C2]malate from [1,4-13C2]fumarate is a marker of cell necrosis and treatment response in tumors. Proc Natl Acad Sci U S A. 2009; 106(47):19801-6. PMC: 2785247. DOI: 10.1073/pnas.0911447106. View

19.

Burgess S, Weis B, Jones J, Smith E, Merritt M, Margolis D . Noninvasive evaluation of liver metabolism by 2H and 13C NMR isotopomer analysis of human urine. Anal Biochem. 2003; 312(2):228-34. DOI: 10.1016/s0003-2697(02)00465-7. View

20.

Hu S, Chen A, Zierhut M, Bok R, Yen Y, Schroeder M . In vivo carbon-13 dynamic MRS and MRSI of normal and fasted rat liver with hyperpolarized 13C-pyruvate. Mol Imaging Biol. 2009; 11(6):399-407. PMC: 2763080. DOI: 10.1007/s11307-009-0218-z. View