Oxygen Glucose Deprivation in Rat Hippocampal Slice Cultures Results in Alterations in Carnitine Homeostasis and Mitochondrial Dysfunction

Thomas F. Rau, Qing Lu, Shruti Sharma, Xutong Sun, Gregory Leary, Matthew L. Beckman, Yali Hou, Mark S. Wainwright, Michael Kavanaugh, David J. Poulsen, Stephen Matthew Black

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Mitochondrial dysfunction characterized by depolarization of mitochondrial membranes and the initiation of mitochondrial-mediated apoptosis are pathological responses to hypoxia-ischemia (HI) in the neonatal brain. Carnitine metabolism directly supports mitochondrial metabolism by shuttling long chain fatty acids across the inner mitochondrial membrane for beta-oxidation. Our previous studies have shown that HI disrupts carnitine homeostasis in neonatal rats and that L-carnitine can be neuroprotective. Thus, this study was undertaken to elucidate the molecular mechanisms by which HI alters carnitine metabolism and to begin to elucidate the mechanism underlying the neuroprotective effect of L-carnitine (LCAR) supplementation. Utilizing neonatal rat hippocampal slice cultures we found that oxygen glucose deprivation (OGD) decreased the levels of free carnitines (FC) and increased the acylcarnitine (AC): FC ratio. These changes in carnitine homeostasis correlated with decreases in the protein levels of carnitine palmitoyl transferase (CPT) 1 and 2. LCAR supplementation prevented the decrease in CPT1 and CPT2, enhanced both FC and the AC:FC ratio and increased slice culture metabolic viability, the mitochondrial membrane potential prior to OGD and prevented the subsequent loss of neurons during later stages of reperfusion through a reduction in apoptotic cell death. Finally, we found that LCAR supplementation preserved the structural integrity and synaptic transmission within the hippocampus after OGD. Thus, we conclude that LCAR supplementation preserves the key enzymes responsible for maintaining carnitine homeostasis and preserves both cell viability and synaptic transmission after OGD.

Original languageEnglish (US)
Article numbere40881
JournalPloS one
Volume7
Issue number9
DOIs
StatePublished - Sep 11 2012

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Carnitine
carnitine
Rats
homeostasis
Homeostasis
Oxygen
oxygen
Glucose
glucose
rats
ischemia
Metabolism
hypoxia
synaptic transmission
Ischemia
Mitochondrial Membranes
Membranes
metabolism
Synaptic Transmission
preserves

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

Cite this

Oxygen Glucose Deprivation in Rat Hippocampal Slice Cultures Results in Alterations in Carnitine Homeostasis and Mitochondrial Dysfunction. / Rau, Thomas F.; Lu, Qing; Sharma, Shruti; Sun, Xutong; Leary, Gregory; Beckman, Matthew L.; Hou, Yali; Wainwright, Mark S.; Kavanaugh, Michael; Poulsen, David J.; Black, Stephen Matthew.

In: PloS one, Vol. 7, No. 9, e40881, 11.09.2012.

Research output: Contribution to journalArticle

Rau, TF, Lu, Q, Sharma, S, Sun, X, Leary, G, Beckman, ML, Hou, Y, Wainwright, MS, Kavanaugh, M, Poulsen, DJ & Black, SM 2012, 'Oxygen Glucose Deprivation in Rat Hippocampal Slice Cultures Results in Alterations in Carnitine Homeostasis and Mitochondrial Dysfunction', PloS one, vol. 7, no. 9, e40881. https://doi.org/10.1371/journal.pone.0040881
Rau, Thomas F. ; Lu, Qing ; Sharma, Shruti ; Sun, Xutong ; Leary, Gregory ; Beckman, Matthew L. ; Hou, Yali ; Wainwright, Mark S. ; Kavanaugh, Michael ; Poulsen, David J. ; Black, Stephen Matthew. / Oxygen Glucose Deprivation in Rat Hippocampal Slice Cultures Results in Alterations in Carnitine Homeostasis and Mitochondrial Dysfunction. In: PloS one. 2012 ; Vol. 7, No. 9.
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