Metabolic alteration transients during paroxysmal activity in an epileptic patient with fixation-off sensitivity: a case study

Giove, Federico; Garreffa, Girolamo; Peca, Stefano; Carnì, Marco; Macrì, Monica; Bonaventura, Carlo Di; Vaudano, Anna Elisabetta; Giallonardo, Anna Teresa; Prencipe, Massimiliano; Bozzao, L.; Pantano, Patrizia; Colonnese, Claudio; Maraviglia, B.

doi:10.1016/j.mri.2005.11.003

Cited by 3 publications

(3 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our previous MRS investigation on a FOS patient, we observed that during FOS activation [Glx] increased in a linear trend (12). However, the experimental design utilized in that study did not allow us to observe the return of [Glx] to baseline.…”

Section: Introductionmentioning

confidence: 85%

“…MRS has been used in functional applications, in order to detect dynamic metabolic variations related to a stimulus in healthy subjects (1)(2)(3)(4)(5)(6)(7)(8), or to spontaneous or stimulus-induced pathologic activity in patients (9)(10)(11)(12). Useful insights may also emerge by comparing MRS data with separately acquired recordings of electroencephalography (EEG), a technique that has a comparably very high temporal resolution and provides information on the brain's electrical activity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Metabolic correlatives of brain activity in a FOS epilepsy patient

et al. 2009

Self Cite

View full text Add to dashboard Cite

The correlation and the interactions between neuronal activity and underlying metabolic dynamics are still a matter of debate, especially in pathological conditions. This study reports findings obtained on a subject suffering from fixation-off sensitivity (FOS) epilepsy, exploited as a model system of triggerable anomalous electrical activity. Functional Magnetic Resonance Spectroscopy was used to investigate the metabolic response to visual spike-inducing stimuli in a single voxel placed in the temporo-occipital lobe of a FOS epilepsy patient. MRS measurements were additionally performed on a control group of five healthy volunteers. The FOS patient also underwent an EEG session with the same stimulus paradigm. Uniquely in the FOS patient, glutamate and glutamine concentration increased during the first 10 min of stimulation and then returned to baseline. On the other hand, FOS-induced epileptic activity (spiking) endured throughout all the stimulation epoch. The observed metabolic dynamics may be likely linked to a complex interplay between alterations of the metabolic pathways of glutamate and modulation of the neuronal activity.

show abstract

Section: Introductionmentioning

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Metabolic correlatives of brain activity in a FOS epilepsy patient

et al. 2009

Self Cite

View full text Add to dashboard Cite

show abstract

“…To address discrepancies between in vivo and slice studies we took advantage of the increased demand on glutamate synthetic pathways during epileptiform activity (Bacci et al, 2002; Otsuki et al, 2005; Giove et al, 2006; Tani et al, 2007) to create a dependence on the cycle. Using pharmacologically disinhibited neocortex, a simple model in which electrically evoked activity can be modulated by the intensity of the stimulus (Courtney and Prince, 1977; Gutnick et al, 1982) and epileptiform events can be analyzed as a readout of neuronal activity (Aram and Lodge, 1988), we demonstrate that synthesis of glutamine in astrocytes and its transfer to neurons are essential for sustained excitatory neuronal activity.…”

Section: Introductionmentioning

confidence: 99%

Glutamine Is Required for Persistent Epileptiform Activity in the Disinhibited Neocortical Brain Slice

Tani¹,

Dulla²,

Huguenard³

et al. 2010

J. Neurosci.

View full text Add to dashboard Cite

The neurotransmitter glutamate is recycled through an astrocytic-neuronal glutamate-glutamine cycle in which synaptic glutamate is taken up by astrocytes, metabolized to glutamine, and transferred to neurons for conversion back to glutamate and subsequent release. The extent to which neuronal glutamate release is dependent upon this pathway remains unclear. Here we provide electrophysiological and biochemical evidence that in acutely disinhibited rat neocortical slices, robust release of glutamate during sustained epileptiform activity requires that neurons be provided a continuous source of glutamine. We demonstrate that the uptake of glutamine into neurons for synthesis of glutamate destined for synaptic release is not strongly dependent on the system A transporters, but requires another unidentified glutamine transporter or transporters. Finally, we find that the attenuation of network activity through inhibition of neuronal glutamine transport is associated with reduced frequency and amplitude of spontaneous events detected at the single-cell level. These results indicate that availability of glutamine influences neuronal release of glutamate during periods of intense network activity.

show abstract

Astrocytic energy metabolism and glutamate formation — relevance for 13C-NMR spectroscopy and importance of cytosolic/mitochondrial trafficking

Hertz¹

2011

Magnetic Resonance Imaging

View full text Add to dashboard Cite

Metabolic alteration transients during paroxysmal activity in an epileptic patient with fixation-off sensitivity: a case study

Cited by 3 publications

References 54 publications

Metabolic correlatives of brain activity in a FOS epilepsy patient

Metabolic correlatives of brain activity in a FOS epilepsy patient

Glutamine Is Required for Persistent Epileptiform Activity in the Disinhibited Neocortical Brain Slice

Astrocytic energy metabolism and glutamate formation — relevance for 13C-NMR spectroscopy and importance of cytosolic/mitochondrial trafficking

Contact Info

Product

Resources

About