Regional aerobic glycolysis in the human brain

Department of Radiology, Washington University, St. Louis, MO 63110, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 10/2010; 107(41):17757-62. DOI: 10.1073/pnas.1010459107
Source: PubMed

ABSTRACT Aerobic glycolysis is defined as glucose utilization in excess of that used for oxidative phosphorylation despite sufficient oxygen to completely metabolize glucose to carbon dioxide and water. Aerobic glycolysis is present in the normal human brain at rest and increases locally during increased neuronal activity; yet its many biological functions have received scant attention because of a prevailing energy-centric focus on the role of glucose as substrate for oxidative phosphorylation. As an initial step in redressing this neglect, we measured the regional distribution of aerobic glycolysis with positron emission tomography in 33 neurologically normal young adults at rest. We show that the distribution of aerobic glycolysis in the brain is differentially present in previously well-described functional areas. In particular, aerobic glycolysis is significantly elevated in medial and lateral parietal and prefrontal cortices. In contrast, the cerebellum and medial temporal lobes have levels of aerobic glycolysis significantly below the brain mean. The levels of aerobic glycolysis are not strictly related to the levels of brain energy metabolism. For example, sensory cortices exhibit high metabolic rates for glucose and oxygen consumption but low rates of aerobic glycolysis. These striking regional variations in aerobic glycolysis in the normal human brain provide an opportunity to explore how brain systems differentially use the diverse cell biology of glucose in support of their functional specializations in health and disease.

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    Human Brain Mapping 06/2015; DOI:10.1002/hbm.22878 · 6.92 Impact Factor
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    • "Such heterogeneities may indeed be expected due to possible regional differences in the neurovascular coupling (Devonshire et al., 2012), aerobic glycolysis (Vaishnavi et al., 2010) and/or in the hemodynamic function (Badillo et al., 2013), which link functional activation and BOLD signal changes. To this purpose, an anatomical parcellation, obtained applying the automated anatomical labelling (AAL), a digital brain atlas (Tzourio-Mazoyer et al., 2002) which divides the MNI space into a set of 116 volumes of interest, and a functional parcellation obtained pooling, for each of the 7 main resting state networks (Yeo et al., 2011), the corresponding AAL regions were applied. "
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    NeuroImage 03/2015; DOI:10.1016/j.neuroimage.2015.03.017 · 6.36 Impact Factor
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    • "Furthermore , these fluctuations are considered as changes in brain activity not externally induced or voluntarily generated by the subject and represent about 90-95% of the total amount of brain activity (Raichle and Snyder, 2007; Biswal et al., 1995). One of such networks, the so-called Default Mode Network (DMN), has been originally identified as a set of regions consistently suppressed during goal-driven behavior (Shulman et al., 1997; Démonet and Thierry, 2001; Damoiseaux et al., 2006; Fox et al., 2005, 2006; Mantini et al., 2007) and tonically active (Raichle et al., 2001; Vaishnavi et al., 2010) during the resting state condition . This metabolic profile is consistent with peculiar functions of the DMN during restful wakefulness, a conclusion confirmed by more recent local field potential recordings from the cortical surface (Miller et al., 2010; Dastjerdi et al., 2011). "
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    International journal of psychophysiology: official journal of the International Organization of Psychophysiology 02/2015; DOI:10.1016/j.ijpsycho.2015.02.008 · 2.65 Impact Factor
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