Expression and function of AGAT, GAMT and CT1 in the mammalian brain.
Level 5 - mechanism / opinion, no new human data
Narrative review of mechanistic and preclinical literature
PubMed 18652072 · doi:10.1007/978-1-4020-6486-9_4
What was done
This narrative review summarizes literature regarding the expression and functional roles of the creatine-synthesizing enzymes arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT), as well as the creatine transporter CT1, across different cell types in the mammalian central nervous system during development and adulthood.
What was found
No quantitative data, sample sizes, or numerical results are reported in the abstract. The review describes that the mammalian brain widely expresses AGAT, GAMT, and CT1. The adult central nervous system has limited capacity to take up creatine from the periphery and relies predominantly on endogenous synthesis, whereas the embryonic brain appears more dependent on peripheral supply. It also addresses the role of CT1 in transporting guanidinoacetate between cells expressing only AGAT and those expressing only GAMT.
Why it matters
It clarifies how the mammalian central nervous system regulates its own creatine homeostasis across developmental stages, highlighting the shift toward autonomous local synthesis in adulthood.
Limits
The abstract contains no quantitative metrics, statistical analyses, sample sizes, or systematic review search methodology. The reported findings are based on general narrative synthesis of preclinical mammalian models rather than direct human clinical trial data.
Cited by
- supports The human body (including the liver and brain) synthesizes between 1 and 3 grams of creatine per day.