Evidence that lithium Inhibits Export of N-Acetyl-L-Aspartate from Neurons: A Retrospective Study of Canavan Disease and Bipolar Disorder Patients

Received: November 22, 2013 Accepted: December 26, 2013 Published: January 03, 2014 neurons, astrocytes and oligodendrocytes is vital for normal brain function [1]. As such it has been described as the brain’s “operating system” [2]. NAA is synthesized by neurons from acetyl co-enzyme A (AcCoA) with the acetyl group derived from on-going oxidation of glucose (Glc), and from L-aspartate (Asp). NAA is one of the most abundant amino acids present in brain at about 10 mM, most of which at any given moment is stored in neurons that constitute about 50% of brain volume. At about 20 mM it is the most abundant amino acid present in neurons. NAA is not a neurotransmitter but it is the only known precursor for the neurotransmitter N-acetyl-Laspartylglutamate (NAAG), an adduct of NAA and glutamate (Glu) that is also synthesized by and is present in neurons at about 1 mM. The importance of the NAA metabolic system is attested to by the fact that about 1 in 40 Glc molecules taken up by neurons as a source of energy is diverted in order to synthesize an NAA molecule [3].