Evidence supporting a role for N-acetyl-l-aspartate as a molecular water pump in myelinated neurons in the central nervous system An analytical review

@article{Baslow2002EvidenceSA,
  title={Evidence supporting a role for N-acetyl-l-aspartate as a molecular water pump in myelinated neurons in the central nervous system An analytical review},
  author={M. Baslow},
  journal={Neurochemistry International},
  year={2002},
  volume={40},
  pages={295-300}
}
  • M. Baslow
  • Published 2002
  • Chemistry, Medicine, Biology
  • Neurochemistry International
Molecular water pumps (MWPs) are characterized as biochemical systems existing at a compartmental boundary of living cells that can actively pump water against its gradient. A role for the observed intercompartmental transport of N-acetyl-L-aspartate (NAA), between neurons and oligodendrocytes in the CNS, as an efflux MWP for the removal of neuronal metabolic water has been proposed. In this review, accumulating evidence in support of such a role for NAA is presented, and the dynamics of the… Expand
Brain N-acetylaspartate as a molecular water pump and its role in the etiology of canavan disease
  • M. Baslow
  • Biology, Medicine
  • Journal of Molecular Neuroscience
  • 2007
TLDR
Although NAA may perform several functions in the CNS, an important role of NAA appears to be osmoregulatory, and an osmotic-hydrostatic mechanism for the etiology of the CD phenotype is proposed. Expand
Brain damage results in down-regulation of N-acetylaspartate as a neuronal osmolyte
TLDR
The results of this study indicate that the buildup of N AA is not required for viability of neurons in monocellular cultures, and that NAA is lost from multicellular cultured brain slice explants that contain viable neurons, and therefore, loss of NAA does not necessarily indicate either loss of neurons or their function. Expand
N-Acetylaspartate in the Vertebrate Brain: Metabolism and Function
  • M. Baslow
  • Biology, Medicine
  • Neurochemical Research
  • 2004
TLDR
Although NAA may have several functions in the CNS, an important role of the NAA intercompartmental system is osmoregulatory, and in this role it may be the primary mechanism for the removal of intracellular water, against a water gradient, from myelinated neurons. Expand
Effect of N-acetylaspartic acid on the diffusion coefficient of water: a proton magnetic resonance phantom method for measurement of osmolyte-obligated water.
TLDR
Using a proton nuclear magnetic resonance method and diffusion measurements at two magnetic field strengths on water and NAA phantoms in vitro, the effect of NAA on the diffusion coefficient of water has been measured, and a ratio (K) of obligated water molecules per molecule of N AA has been determined. Expand
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TLDR
It is hypothesize that NAA conversion to glutamate is a logical and favorable use of this highly concentrated metabolite, and future studies to demonstrate the chemical, metabolic and pathological links between NAA and glutamate will support this hypothesis. Expand
N-Acetylaspartate in the CNS: From neurodiagnostics to neurobiology
TLDR
Evidence suggests that NAA is a direct precursor for the enzymatic synthesis of the neuron specific dipeptides N-acetylaspartylglutamate, the most concentrated neuropeptide in the human brain, and it is proposed that N AA may also be involved in brain nitrogen balance. Expand
N-acetylaspartate in brain - studies on efflux and function
N-acetylaspartate (NAA) is an amino acid derivative present in high concentration in the brain. The function of NAA is still unsettled in spite of 50 years of research. The mainly neuronal synthesisExpand
Investigation of the neuronal marker N-acetylaspartate as a potential biomarker for neurological diseases
N-acetylaspartate (NAA) is known to be present in high concentrations throughout the whole CNS. It is believed to have four basic functions in the brain; an organic osmolyte, a source of acetate forExpand
N-Acetylaspartate Metabolism Underlays the Structural and FunctionalUnits of the Vertebrate Brain: A Bioenergetic Rationale for ClinicalObservations of Changes in the Neuronal Biomarker âÂÂNAAâ in manyHuman Brain Disorders
TLDR
The hierarchal structural and functional units of the brain are described, a bioenergetic rationale for using the NAA-NAAG metabolic system as a biomarker for neuronal abundance and/or viability is presented, and examples of some human diseases that can be traced to interference with one or more components of structural or functional units are provided. Expand
An anti-inflammatory role for N-acetyl aspartate in stimulated human astroglial cells.
TLDR
It is demonstrated that NAA appears to be important in the modulation of inflammation in the human STTG astroglial cell line and neuronal pathologies that exhibit abnormal NAA levels within the brain are discussed. Expand
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