The elevation of choline-containing metabolites [phosphocholine (PC), glycerophosphocholine
(GPC), free choline (Cho)] and the over and under-expression of key enzymes in phospholipid membrane synthesis and degradation, specifically choline kinase and a number of the phospholipases have been associated with the presence, progression and therapeutic response of a variety of human cancers including prostate.
Also, high levels of glycerophosphocholine
(GPC) were detected in human breast cancer biopsies and xenograft (35).
In tissues and foods, there are several choline compounds that contribute to the total choline concentration (choline, glycerophosphocholine
, phosphocholine, phosphatidylcholine and sphingomyelin).
Shin et al., "Glycerophosphocholine
Metabolites and Cardiovascular Disease Risk Factors in Adolescents: A Cohort Study," Circulation, vol.
In locally advanced breast cancer treated with doxorubicin, a decrease in glycerophosphocholine
predicted long-term survival and response to treatment .
PNPLA6 (i[PLA.sub.2][delta]) and its closest paralog PNPLA7 (i[PLA.sub.2][theta]) have lysophospholipase activity that cleaves lysophosphatidylcholine to yield fatty acid and glycerophosphocholine
. (47,48) Genetic mutations or deletions of these phospholipid-targeting PNPLAs cause various forms of metabolic dysfunction and neurodegeneration.
It has been shown in rodents that organic osmolytes such as L-carnitine, glycerophosphocholine
, D-glutamate and myo-inositol are present in millimolar concentrations, which are 1,000 times higher than the blood.8 Ultimately, the hyperosmotic epididymal fluid is intended to load spermatozoa with these osmolytes and can act as reserves with higher intracellular concentrations in mature spermatozoa.9
Fuchs, "HOCl-mediated glycerophosphocholine
and glycerophosphoethanolamine generation from plasmalogens in phospholipid mixtures," Lipids, vol.
Nieschlag, "The influence of inflammation of the human male genital tract on secretion of the seminal markers [alpha]-glucosidase, glycerophosphocholine
, carnitine, fructose and citric acid," International Journal of Andrology, vol.
Calcium-dependent phospholipase A2 (cPLA2) and iPLA2 use phosphatidylcholines as substrate to form arachidonic acid, a precursor of several lipid mediators, and lysophosphatidylcholines, a metabolite that can be further degraded to glycerophosphocholine
, phosphocholine, or lysophosphatidic acid and choline [22, 23].
Increases in NMR-visible lipid and glycerophosphocholine
during phenylbutyrate-induced apoptosis in human prostate cancer cells.
The lipid profiles from normal brain tissues were clearly distinct from glioma tissues, and consistently showed increased abundances of the lipids glycerophosphocholine
(PC 34:1) and glycerophosphoinositol (PI 38:4).