Neurochemical Research

, Volume 34, Issue 7, pp 1195–1203

Glial Metabolism of Valine

  • Radovan Murín
  • Ghasem Mohammadi
  • Dieter Leibfritz
  • Bernd Hamprecht
ORIGINAL PAPER

DOI: 10.1007/s11064-008-9895-2

Cite this article as:
Murín, R., Mohammadi, G., Leibfritz, D. et al. Neurochem Res (2009) 34: 1195. doi:10.1007/s11064-008-9895-2

Abstract

The three essential amino acids, valine, leucine and isoleucine, constitute the group of branched-chain amino acids (BCAAs). BCAAs are rapidly taken up into the brain parenchyma, where they serve several distinct functions including that as fuel material in brain energy metabolism. As one function of astrocytes is considered the production of fuel molecules that support the energy metabolism of adjacent neural cells in brain. Astroglia-rich primary cultures (APC) were shown to rapidly dispose of the BCAAs, including valine, contained in the culture medium. While the metabolisms of leucine and isoleucine by APC have already been studied in detail, some aspects of valine metabolism remained to be determined. Therefore, in the present study an NMR analysis was performed to identify the 13C-labelled metabolites that are generated by APC during catabolism of [U-13C]valine and that are subsequently released into the incubation medium. The results presented show that APC (1) are potently disposing of the valine contained in the incubation medium; (2) are capable of degrading valine to the tricarboxylic acid (TCA) cycle member succinyl-CoA; and (3) release into the extracellular milieu valine catabolites and compounds generated from them such as [U-13C]2-oxoisovalerate, [U-13C]3-hydroxyisobutyrate, [U-13C]2-methylmalonate, [U-13C]isobutyrate, and [U-13C]propionate as well as several TCA cycle-dependent metabolites including lactate.

Keywords

Astroglia Energy metabolism Valine Branched-chain amino acid Branched-chain 2-oxoacid 2-Oxoisovalerate 3-Hydroxyisobutyrate 

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Radovan Murín
    • 1
  • Ghasem Mohammadi
    • 2
  • Dieter Leibfritz
    • 2
  • Bernd Hamprecht
    • 1
  1. 1.Interfaculty Institute for BiochemistryUniversity of TuebingenTuebingenGermany
  2. 2.Institute for Organic ChemistryUniversity of BremenBremenGermany

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