Sarcosine

Sarcosine is the N-methyl derivative of glycine. It is a natural amino acid found in muscles and other body tissues. In the laboratory, it may be synthesized from chloroacetic acid and methylamine. Sarcosine is found naturally as an intermediate in the metabolism of choline to glycine. Sarcosine is sweet to the taste and dissolves in water. It is used in manufacturing biodegradable surfactants and toothpastes as well as in other applications.

Sarcosine is ubiquitous in biological materials and is present in such foods as egg yolks, turkey, ham, vegetables, legumes, etc.

Sarcosine is reported to be formed from dietary intake of choline and from the metabolism of methionine and is rapidly degraded to glycine, which, in addition to its importance as a constituent of protein, plays a significant role in various physiological processes as a prime metabolic source of components of living cells such as glutathione, creatine, purines and serine. The concentration of sarcosine in blood serum of normal human subjects is reported to be 1.59 ± 1.08 micromoles per liter.

Sarcosine has no known toxicity, as evidenced by the lack of phenotypic manifestations of sarcosinemia, an inborn error of sarcosine metabolism. Sarcosinemia can result from severe folate deficiency because of the folate requirement for the conversion of sarcosine to glycine.

Recently, sarcosine has been investigated in relation to the mental illness schizophrenia. Early evidence suggests that intake of 2 g/day sarcosine as add-on therapy to certain antipsychotics (not clozapine ) in schizophrenia gives significant additional reductions in both positive and negative symptomatology as well as the neurocognitive, general psychiatric and depressive symptoms that are common to the illness. Sarcosine had been tolerated well. It is also under investigation for the possible prevention of schizophrenic illness during the prodromal stage of the disease. It acts as a type 1 glycine transporter inhibitor. It increases glycine concentrations in the brain thus causing increased NMDA receptor activation and a reduction in symptoms. As such, it might be an interesting treatment option and a possible new direction in the treatment of the mental illness in the future.

Sarcosine was first isolated and named by the German chemist Justus von Liebig in 1847, while Jacob Volhard first synthezised it in 1862.