Metabolic Flux Analysis Tools to Investigate Brain Metabolism In Vitro

Abstract

AbstractIn recent decades, 13C nuclear magnetic resonance (NMR) spectroscopy and metabolic modeling tools allowed estimating the main cerebral metabolic fluxes in vitro and in vivo. These investigations contributed significantly to elucidate neuro-glial metabolic interactions, cerebral metabolic compartmentation, and the individual contribution of neurons and astrocytes to brain energetics. However, many issues in this field remain unclear and/or under debate.Despite the valuable amount of data generated in cell culture studies involving 13C-labeled substrates and NMR spectroscopy or mass spectrometry, only a few studies have employed modeling approaches to fully explore the results obtained. Here, we present different Metabolic Flux Analysis (MFA) methodologies that, combined with information provided by isotopomers of key compounds derived from the metabolism of 13C-labeled precursors, allow for a more comprehensive investigation of cell metabolism in cultured brain cells. Overall, MFA is presented as a powerful tool to investigate particular aspects of cerebral metabolic compartmentation in the context of physiology and disease as it allows quantifying changes in the distribution of metabolic fluxes caused by pathological insults, drug treatments, or presence of different metabolic substrates.Key wordsBrain energy metabolismMetabolic flux analysisPrimary culturesAstrocytesNeurons 13C glucose 13C NMR spectroscopyGas chromatography–mass spectrometry