Glycerophosphocholine enhances growth hormone secretion and fat oxidation in young adults.
OBJECTIVE
α-Glycerophosphocholine (GPC) is a putative acetylcholine precursor that potentially increases growth hormone secretion through the action of acetylcholine-stimulated catecholamine. The aim of this study was to investigate acute physiologic responses to a single intake of GPC.


METHODS
Eight healthy male subjects (25 ± 1 y old) ingested GPC 1000 mg or a placebo in a double-blind randomized crossover study. Fasting blood samples were obtained before the administration of GPC (baseline) and 60 and 120 min after administration. All subjects repeated the identical protocol using the placebo.


RESULTS
Plasma free choline levels significantly increased at 60 and 120 min after GPC administration. Plasma growth hormone secretion was increased significantly 60 min after taking GPC, whereas no significant change was observed with the placebo. In addition, the serum free fatty acid was increased 120 min after GPC ingestion, but no changes were seen with the placebo. Moreover, serum acetoacetate and 3-hydroxybutyrate levels, which are indices of hepatic fat oxidation, were increased at 120 min after taking GPC, whereas the placebo had no effect.


CONCLUSIONS
These findings suggest that a single dose of GPC increases growth hormone secretion and hepatic fat oxidation, with concomitant increases in choline levels, in young adults.
Faculty of Sport and Health Science, Ritsumeikan University, Shiga, Japan.
Takashi
T
Kawamura
Takeshi
T
Okubo
Koji
K
Sato
Satoshi
S
Fujita
Kazushige
K
Goto
Takafumi
T
Hamaoka
Motoyuki
M
Iemitsu
D020155:3-Hydroxybutyric Acid / Q000097:blood; D000090:Acetoacetates / Q000097:blood; D000328:Adult; D002794:Choline / Q000097:blood; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005997:Glycerylphosphorylcholine / Q000378:metabolism*; D019382:Human Growth Hormone / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D015203:Reproducibility of Results; D015854:Up-Regulation; D055815:Young Adult
D000090:Acetoacetates; D005230:Fatty Acids, Nonesterified; D019382:Human Growth Hormone; C016635:acetoacetic acid; D005997:Glycerylphosphorylcholine; D002794:Choline; D020155:3-Hydroxybutyric Acid