Elsevier

Neuroscience

Volume 106, Issue 4, 31 October 2001, Pages 669-677
Neuroscience

Neurotoxicity of glutamate uptake inhibition in vivo: correlation with succinate dehydrogenase activity and prevention by energy substrates

https://doi.org/10.1016/S0306-4522(01)00323-2Get rights and content

Abstract

Impairment of glutamate uptake or the reverse action of its transporters has been suggested as the mechanism responsible for the increased glutamate extracellular levels associated with ischemic neuronal damage. In previous studies we have shown that glutamate uptake inhibition by L-trans-pyrrolidine-2,4-dicarboxylate (PDC) in the rat striatum and hippocampus in vivo does not induce neuronal death despite the notable increase in the extracellular levels of glutamate and aspartate. However, PDC intracerebral administration leads to neuronal death in rats chronically injected with the mitochondrial toxin 3-nitropropionic acid (3-NP), an inhibitor of succinate dehydrogenase (SDH). In the present study we have determined the time course of inhibition of SDH activity in the striatum of rats acutely injected with a single dose of 3-NP (20 mg/kg), and studied its relation to PDC neurotoxicity. PDC induced larger lesions when administered during maximum inhibition of SDH activity while smaller lesions were found when it was injected during recovery of enzyme activity. We also studied the neuroprotective effect of different energy substrates such as creatine, pyruvate, and the ketone bodies β-hydroxybutyrate and acetoacetate in this experimental model. Our results show partial protection with all compounds except for β-hydroxybutyrate that showed no protection, while MK-801 completely prevented PDC-induced neuronal damage.

We believe that the present results might be of relevance for the understanding of the mechanisms responsible for ischemic neuronal death and its prevention.

Section snippets

Animal treatment

Male Wistar rats (250–290 g) were used throughout the study. They were handled according to the Rules for Research in Health Matters (Mexico) and the local Animal Care Committee approved all animal treatments. All efforts were made to minimize the number of animals used and their suffering. All animals received a single i.p. injection of 3-NP (20 mg/kg) dissolved in 10 mM phosphate buffer (pH adjusted to 7.0–7.5 with 1 M NaOH) and 4, 24 or 48 h later they received an intrastriatal

Correlation between neurotoxicity of PDC and SDH activity

The time course of SDH activity after a single i.p. administration of 3-NP (20 mg/kg) was determined histochemically as described in the Experimental procedures. According to this analysis SDH activity was maximally inhibited 2–4 h after 3-NP injection while no inhibition was found at 1 h. Enzyme activity was almost completely recovered at 48 h (Fig. 1A). According to the statistical analysis no difference was found between the 1 h and the 48 h groups while differences were found between the 1

Discussion

Previous in vivo microdialysis experiments indicate that intrastriatal administration of the substrate inhibitor of glutamate transporters, PDC, leads to substantial elevation of the extracellular levels of excitatory amino acids, reaching aspartate and glutamate concentrations higher than 50 and 100 μM, respectively (considering 6–7% membrane recovery for these amino acids (Massieu et al., 1995, Sánchez-Carbente and Massieu, 1999)). PDC-induced glutamate release in vivo probably occurs through

Conclusion

The present study shows that induction of the reverse action of glutamate transporters by PDC leads to neuronal death in the rat striatum in vivo when mitochondrial energy metabolism is partially and transiently inhibited. The present results also suggest the potential of energy substrates such as creatine, pyruvate and acetoacetate as neuroprotective agents against ischemic neuronal damage.

Acknowledgements

The authors thank Mr. Federico Jandete for his help in histological work. This work was supported by CONACYT 27970N and UNAM (DGAPA IN203400).

References (55)

  • R Blitzblau et al.

    The glutamate transport inhibitor L-trans-pyrrolidine-2,4-dicarboxylate indirectly evokes NMDA receptor mediated neurotoxicity in rat cortical cultures

    Eur. J. Neurosci.

    (1996)
  • G.J Brewer et al.

    Protective effect of the energy precursor creatine against toxicity of glutamate and β-amyloid in rat hippocampal neurons

    J. Neurochem.

    (2000)
  • R.J Bridges et al.

    Conformationally defined neurotransmitter analogs. Selective inhibition of glutamate uptake by one pyrrolidine-2,4-dicarboxylate diastereomer

    J. Med. Chem.

    (1991)
  • E Brouillet et al.

    Partial inhibition of brain succinate dehydrogenase by 3-nitropropionic acid is sufficient to initiate striatal degeneration in rat

    J. Neurochem.

    (1998)
  • N Brustovetsky et al.

    On the mechanisms of neuroprotection by creatine and phosphocreatine

    J. Neurochem.

    (2001)
  • J.T Coyle et al.

    Oxidative stress, glutamate and neurodegenerative disorders

    Science

    (1993)
  • Y Daikhin et al.

    Ketone bodies and brain glutamate and GABA metabolism

    Dev. Neurosci.

    (1998)
  • S Desagher et al.

    Pyruvate protects neurons against hydrogen peroxide-induced toxicity

    J. Neurosci.

    (1997)
  • S.B Desphande et al.

    3-Nitropropionic acid increases the intracellular Ca2+ in cultured astrocytes by reverse operation of the Na+–Ca2+ exchanger

    Exp. Neurol.

    (1997)
  • S Eimerl et al.

    Resuscitation of brain neurons in the presence of Ca2+ after toxic NMDA-receptor activity

    J. Neurochem.

    (1995)
  • A.I Faden et al.

    The role of excitatory amino acids and NMDA receptors in traumatic brain injury

    Science

    (1989)
  • O Garcı́a et al.

    Strategies of neuroprotection against L-trans-2,4-pyrrolidine dicarboxylate-induced neuronal damage during energy impairment in vitro

    J. Neurosci. Res.

    (2001)
  • M.Y.-T Globus et al.

    Effect of ischemia on the release of striatal dopamine, glutamate, and γ-aminobutyric acid studied by intracerebral microdialysis

    J. Neurochem.

    (1988)
  • B.F Hamilton et al.

    Nature and distribution of brain lesions in rats intoxicated with 3-nitropropionic acid: a type of hypoxic (energy deficient) brain damage

    Acta Neuropathol.

    (1987)
  • P.S Hodgkins et al.

    Interference with cellular energy metabolism reduces kynurenic acid formation in rat brain slices: reversal by lactate and pyruvate

    Eur. J. Neurosci.

    (1998)
  • P.S Hodgkins et al.

    Metabolic control of kynurenic acid formation in the rat brain

    Dev. Neurosci.

    (1998)
  • C Ikonomidou et al.

    Excitotoxicity and neurodegenerative diseases

    Curr. Opin. Neurol.

    (1995)
  • Cited by (49)

    • Mitochondrial dynamics in neurodegeneration

      2013, Trends in Cell Biology
      Citation Excerpt :

      Neurodegeneration occurs in the striatum during early pathogenesis, but broad areas of the brain are also affected during later stages of disease progression. As with AD and PD, considerable evidence has implicated mitochondrial failure in the pathogenesis of HD [109], and striatal neurons that degenerate in HD are remarkably susceptible to inhibition of complex II [110,111]. More recently, changes in mitochondrial dynamics have also been found in HD.

    View all citing articles on Scopus
    View full text