N-Acetylaspartic acid

Function

The various functions served by NAA are under investigation, but the primary proposed functions include:

• Neuronal osmolyte that is involved in fluid balance in the brain
• Source of acetate for lipid and myelin synthesis in oligodendrocytes, the glial cells that myelinate neuronal axons
• Precursor for the synthesis of the neuronal dipeptide N-Acetylaspartylglutamate
• Contributor to energy production from the amino acid glutamate in neuronal mitochondria.

In the brain, NAA was thought to be present predominantly in neuronal cell bodies, where it acts as a neuronal marker, but it is also free to diffuse throughout neuronal fibers.

Applications

However, the recent discovery of a higher concentration of NAA in myelin and oligodendrocytes than in neurons raises questions about the validity of the use of NAA as a neuronal marker. NAA gives off the largest signal in magnetic resonance spectroscopy of the human brain. The levels measured there are decreased in numerous neuropathological conditions ranging from brain injury to stroke to Alzheimer's disease. This fact makes NAA a potential diagnostic molecule for doctors treating patients with brain damage or disease.

NAA may be a marker of creativity. High NAA levels in the hippocampus are related to better working memory performance in humans. Whole-brain levels of NAA have also been found to be positively correlated with educational attainment in adults. | access-date =

NAA may function as a neurotransmitter in the brain by acting on metabotropic glutamate receptors.

References

References

1. (26 March 2005). "N-acetylaspartate - Compound Summary". National Center for Biotechnology Information.
2. (1991). "Immunocytochemical localization of N-acetyl-aspartate with monoclonal antibodies". Neuroscience.
3. (March 2015). "Localisation of N-acetylaspartate in oligodendrocytes/myelin". Brain Structure & Function.
4. (December 1979). "Synthesis of N-acetyl-L-aspartate by rat brain mitochondria and its involvement in mitochondrial/cytosolic carbon transport". The Biochemical Journal.
5. (2001). "Nuclear magnetic resonance spectroscopy and imaging in animal research". ILAR Journal.
6. (April 2016). "Brain intracellular metabolites are freely diffusing along cell fibers in grey and white matter, as measured by diffusion-weighted MR spectroscopy in the human brain at 7 T". Brain Structure & Function.
7. Geddes, Linda. "Creativity chemical favours the smart".
8. (2012). "Working memory and N-acetylaspartate level in hippocampus, parietal cortex and subventricular zone". International Journal of Psychology.
9. (September 2003). "Activation by N-acetyl-L-aspartate of acutely dissociated hippocampal neurons in rats via metabotropic glutamate receptors". Epilepsia.