Impaired Pentose Phosphate Pathway in the Spinal Cord of the hSOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis
Impairments in energy metabolism in amyotrophic lateral sclerosis (ALS) have long been known. However, the changes in the energy-producing pathways in ALS are not comprehensively understood. To investigate specific alterations in glucose metabolism in glycolytic, pentose phosphate, and TCA cycle pathways, we injected uniformly labeled [U-13C]glucose to wild-type and hSOD1G93A mice at symptom onset (80 days). Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), levels of metabolites were determined in extracts of the cortex and spinal cord. In addition, the activities of several enzymes involved in glucose metabolism were quantified. In the spinal cord, the levels of pentose phosphate pathway (PPP) intermediate ribose 5-phosphate (p = 0.037) were reduced by 37% in hSOD1G93A mice, while the % 13C enrichments in glucose 6-phosphate were increased threefold. The maximal activities of the enzyme glucose 6-phosphate dehydrogenase were decreased by 24% in the spinal cord (p = 0.005), suggesting perturbations in the PPP. The total amount of pyruvate in the cortex (p = 0.039) was reduced by 20% in hSOD1G93A mice. Also, the activities of the glycolytic enzyme pyruvate kinase were reduced in the cortex by 31% (p = 0.002), indicating alterations in glycolysis. No significant differences were seen in the total amounts as well as % 13C enrichments in most TCA cycle intermediates, suggesting largely normal TCA cycle function. On the other hand, oxoglutarate dehydrogenase activity was decreased in the cortex, which may indicate increased oxidative stress. Overall, this study revealed decreased activity of the PPP in the spinal cord and alterations in glycolysis in hSOD1G93A mouse CNS tissues at the early symptomatic stage of disease.
KeywordsEnergy metabolism Glycolysis Liquid chromatography-tandem mass spectrometry Motor neuron disease Pentose phosphate pathway TCA cycle
We wish to thank the Queensland Brain Institute and Dr. Shuyan Ngo for providing animals. TWT is a recipient of The University of Queensland International scholarship.
This work was supported by the Motor Neurone Disease Research Institute Australia to KB (grant number: GIA 1704).
Compliance with Ethical Standards
All animal experiments were approved by the University of Queensland Animal Ethics Committee (SBMS 128/14) and followed the guidelines of the Queensland Animal Care and Protection Act 2001.
Conflict of Interest
The authors declare that they have no conflicts of interest.
- 7.Dupuis L, Oudart H, Rene F, Gonzalez de Aguilar JL, Loeffler JP (2004) Evidence for defective energy homeostasis in amyotrophic lateral sclerosis: benefit of a high-energy diet in a transgenic mouse model. Proc Natl Acad Sci U S A 101(30):11159–11164. https://doi.org/10.1073/pnas.0402026101 CrossRefPubMedPubMedCentralGoogle Scholar
- 9.Korner S, Hendricks M, Kollewe K, Zapf A, Dengler R, Silani V, Petri S (2013) Weight loss, dysphagia and supplement intake in patients with amyotrophic lateral sclerosis (ALS): impact on quality of life and therapeutic options. BMC Neurol 13:84. https://doi.org/10.1186/1471-2377-13-84 CrossRefPubMedPubMedCentralGoogle Scholar
- 12.Miyazaki K, Masamoto K, Morimoto N, Kurata T, Mimoto T, Obata T, Kanno I, Abe K (2012) Early and progressive impairment of spinal blood flow-glucose metabolism coupling in motor neuron degeneration of ALS model mice. J Cereb Blood Flow Metab 32(3):456–467. https://doi.org/10.1038/jcbfm.2011.155 CrossRefPubMedGoogle Scholar
- 14.Tefera TW, Borges K (2018) Neuronal glucose metabolism is impaired while astrocytic TCA cycling is unaffected at symptomatic stages in the hSOD1(G93A) mouse model of amyotrophic lateral sclerosis. J Cereb Blood Flow Metab:271678X18764775. https://doi.org/10.1177/0271678X18764775
- 17.Veyrat-Durebex C, Corcia P, Piver E, Devos D, Dangoumau A, Gouel F, Vourc'h P, Emond P et al (2015) Disruption of TCA cycle and glutamate metabolism identified by metabolomics in an in vitro model of amyotrophic lateral sclerosis. Mol Neurobiol 53:6910–6924. https://doi.org/10.1007/s12035-015-9567-6 CrossRefPubMedGoogle Scholar
- 18.D'Arrigo A, Colavito D, Pena-Altamira E, Fabris M, Dam M, Contestabile A, Leon A (2010) Transcriptional profiling in the lumbar spinal cord of a mouse model of amyotrophic lateral sclerosis: a role for wild-type superoxide dismutase 1 in sporadic disease? J Mol Neurosci 41(3):404–415. https://doi.org/10.1007/s12031-010-9332-2 CrossRefPubMedGoogle Scholar
- 19.Ferraiuolo L, Higginbottom A, Heath PR, Barber S, Greenald D, Kirby J, Shaw PJ (2011) Dysregulation of astrocyte-motoneuron cross-talk in mutant superoxide dismutase 1-related amyotrophic lateral sclerosis. Brain 134(Pt 9):2627–2641. https://doi.org/10.1093/brain/awr193 CrossRefPubMedPubMedCentralGoogle Scholar
- 24.Medina-Torres CE, van Eps AW, Nielsen LK, Hodson MP (2015) A liquid chromatography-tandem mass spectrometry-based investigation of the lamellar interstitial metabolome in healthy horses and during experimental laminitis induction. Vet J 206(2):161–169. https://doi.org/10.1016/j.tvjl.2015.07.031 CrossRefPubMedGoogle Scholar
- 30.Allen S, Heath PR, Kirby J, Wharton SB, Cookson MR, Menzies FM, Banks RE, Shaw PJ (2003) Analysis of the cytosolic proteome in a cell culture model of familial amyotrophic lateral sclerosis reveals alterations to the proteasome, antioxidant defenses, and nitric oxide synthetic pathways. J Biol Chem 278(8):6371–6383. https://doi.org/10.1074/jbc.M209915200 CrossRefPubMedGoogle Scholar
- 32.Chi L, Ke Y, Luo C, Gozal D, Liu R (2007) Depletion of reduced glutathione enhances motor neuron degeneration in vitro and in vivo. Neuroscience 144(3):991–1003. https://doi.org/10.1016/j.neuroscience.2006.09.064 CrossRefPubMedGoogle Scholar
- 36.Herrero-Mendez A, Almeida A, Fernandez E, Maestre C, Moncada S, Bolanos JP (2009) The bioenergetic and antioxidant status of neurons is controlled by continuous degradation of a key glycolytic enzyme by APC/C-Cdh1. Nat Cell Biol 11(6):747–752. https://doi.org/10.1038/ncb1881 CrossRefPubMedGoogle Scholar
- 37.Dienel GA (2014) Chapter 3 - energy metabolism in the brain. In: From molecules to networks, 3rd edn. Academic, Boston, pp. 53–117. https://doi.org/10.1016/B978-0-12-397179-1.00003-8 CrossRefGoogle Scholar
- 38.D'Alessandro G, Calcagno E, Tartari S, Rizzardini M, Invernizzi RW, Cantoni L (2011) Glutamate and glutathione interplay in a motor neuronal model of amyotrophic lateral sclerosis reveals altered energy metabolism. Neurobiol Dis 43(2):346–355. https://doi.org/10.1016/j.nbd.2011.04.003 CrossRefPubMedGoogle Scholar
- 40.Siciliano G, D'Avino C, Del Corona A, Barsacchi R, Kusmic C, Rocchi A, Pastorini E, Murri L (2002) Impaired oxidative metabolism and lipid peroxidation in exercising muscle from ALS patients. Amyotroph Lateral Scler Other Motor Neuron Disord 3(2):57–62. https://doi.org/10.1080/146608202760196011 CrossRefPubMedGoogle Scholar
- 41.Dodge JC, Treleaven CM, Fidler JA, Tamsett TJ, Bao C, Searles M, Taksir TV, Misra K et al (2013) Metabolic signatures of amyotrophic lateral sclerosis reveal insights into disease pathogenesis. Proc Natl Acad Sci U S A 110(26):10812–10817. https://doi.org/10.1073/pnas.1308421110 CrossRefPubMedPubMedCentralGoogle Scholar
- 44.Tefera TW, Wong Y, Barkl-Luke ME, Ngo ST, Thomas NK, McDonald TS, Borges K (2016) Triheptanoin protects motor neurons and delays the onset of motor symptoms in a mouse model of amyotrophic lateral sclerosis. PLoS One 11(8):e0161816. https://doi.org/10.1371/journal.pone.0161816 CrossRefPubMedPubMedCentralGoogle Scholar
- 45.Ari C, Poff AM, Held HE, Landon CS, Goldhagen CR, Mavromates N, D'Agostino DP (2014) Metabolic therapy with Deanna protocol supplementation delays disease progression and extends survival in amyotrophic lateral sclerosis (ALS) mouse model. PLoS One 9(7):e103526. https://doi.org/10.1371/journal.pone.0103526 CrossRefPubMedPubMedCentralGoogle Scholar
- 46.Matthews RT, Yang L, Browne S, Baik M, Beal MF (1998) Coenzyme Q10 administration increases brain mitochondrial concentrations and exerts neuroprotective effects. Proc Natl Acad Sci U S A 95 (15):8892–8897Google Scholar
- 47.Cassina P, Cassina A, Pehar M, Castellanos R, Gandelman M, de Leon A, Robinson KM, Mason RP, Beckman JS, Barbeito L, Radi R (2008) Mitochondrial dysfunction in SOD1G93A-bearing astrocytes promotes motor neuron degeneration: prevention by mitochondrial-targeted antioxidants. J Neurosci 28(16):4115–4122. https://doi.org/10.1523/JNEUROSCI.5308-07.2008
- 48.Miquel E, Cassina A, Martinez-Palma L, Souza JM, Bolatto C, Rodriguez-Bottero S, Logan A, Smith RA, Murphy MP, Barbeito L, Radi R, Cassina P (2014) Neuroprotective effects of the mitochondria-targeted antioxidant MitoQ in a model of inherited amyotrophic lateral sclerosis. Free Radic Biol Med 70:204–213. https://doi.org/10.1016/j.freeradbiomed.2014.02.019
- 49.Zhao W, Varghese M, Vempati P, Dzhun A, Cheng A, Wang J, Lange D, Bilski A et al (2012) Caprylic triglyceride as a novel therapeutic approach to effectively improve the performance and attenuate the symptoms due to the motor neuron loss in ALS disease. PLoS One 7(11):e49191. https://doi.org/10.1371/journal.pone.0049191 CrossRefPubMedPubMedCentralGoogle Scholar