N-Acetyl aspartate
Encyclopedia
N-Acetylaspartic acid, or N-acetylaspartate (NAA), is a derivative of aspartic acid
with a formula of C6H9NO5 and a molecular weight of 175.139.
NAA is the second-most-concentrated molecule in the brain after the amino acid glutamate. It is synthesized in neurons from the amino acid aspartic acid
and acetyl-coenzyme A
. The various functions served by NAA are still under investigation, but the primary proposed functions include its being:
In the brain, NAA is thought to be present predominantly in neuronal cell bodies, where it acts as a neuronal marker . NAA gives off the largest signal in magnetic resonance spectroscopy
of the human brain, and 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 reliable diagnostic molecule for doctors treating patients with brain damage or disease.
NAA may also be a marker of creativity.
Aspartic acid
Aspartic acid is an α-amino acid with the chemical formula HOOCCHCH2COOH. The carboxylate anion, salt, or ester of aspartic acid is known as aspartate. The L-isomer of aspartate is one of the 20 proteinogenic amino acids, i.e., the building blocks of proteins...
with a formula of C6H9NO5 and a molecular weight of 175.139.
NAA is the second-most-concentrated molecule in the brain after the amino acid glutamate. It is synthesized in neurons from the amino acid aspartic acid
Aspartic acid
Aspartic acid is an α-amino acid with the chemical formula HOOCCHCH2COOH. The carboxylate anion, salt, or ester of aspartic acid is known as aspartate. The L-isomer of aspartate is one of the 20 proteinogenic amino acids, i.e., the building blocks of proteins...
and acetyl-coenzyme A
Acetyl-CoA
Acetyl coenzyme A or acetyl-CoA is an important molecule in metabolism, used in many biochemical reactions. Its main function is to convey the carbon atoms within the acetyl group to the citric acid cycle to be oxidized for energy production. In chemical structure, acetyl-CoA is the thioester...
. The various functions served by NAA are still under investigation, but the primary proposed functions include its being:
- A neuronal osmolyteOsmolyteOsmolytes are compounds affecting osmosis. They are soluble in the solution within a cell, or in the surrounding fluid, e.g. as plasma osmolytes. They play a role in maintaining cell volume and fluid balance. For example, when a cell swells due to external osmotic pressure, membrane channels open...
that is involved in fluid balance in the brain - A source of acetate for lipid and myelin synthesis in oligodendrocyteOligodendrocyteOligodendrocytes , or oligodendroglia , are a type of brain cell. They are a variety of neuroglia. Their main function is the insulation of axons in the central nervous system of some vertebrates...
s, the glial cells that myelinate neuronal axons - A precursor for the synthesis of the important neuronal dipeptide N-AcetylaspartylglutamateN-AcetylaspartylglutamateN-Acetylaspartylglutamic acid is a neuropeptide that is the third-most-prevalent neurotransmitter in the mammalian nervous system. NAAG consists of N-acetylaspartic acid and glutamic acid coupled via a peptide bond...
- A contributor to energy production from the amino acid glutamate in neuronal mitochondria.
In the brain, NAA is thought to be present predominantly in neuronal cell bodies, where it acts as a neuronal marker . NAA gives off the largest signal in magnetic resonance spectroscopy
In vivo magnetic resonance spectroscopy
In vivo magnetic resonance spectroscopy is a specialised technique associated to magnetic resonance imaging ....
of the human brain, and the levels measured there are decreased in numerous neuropathological conditions ranging from brain injury to stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
to Alzheimer's disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...
. This fact makes NAA a reliable diagnostic molecule for doctors treating patients with brain damage or disease.
NAA may also be a marker of creativity.