Inositol phosphoglycan putative insulin mediator in human amniotic fluid.
BACKGROUND
Many hormones such as insulin, insulin-like growth factors, and the glucocorticoids are involved in regulating fetal growth. Inositol phosphoglycans (IPGs), a family of putative second messengers of insulin, are reported to exert several of insulin's metabolic effects.


METHODS
A prospective cross-sectional study was carried out to investigate IPG P-type (P-IPG) in human amniotic fluid and in adult urine under physiological conditions. An amniotic fluid sample was taken from 78 women undergoing early amniocentesis and a mid-stream urine specimen was collected from 109 healthy pregnant and 66 non-pregnant women. All samples were assessed using a polyclonal antibody-based ELISA.


RESULTS
The P-IPG content was a thousand times higher in the amniotic fluid than in the urine (p < 0.0001). Urinary specimens showed a four-fold higher P-IPG content during pregnancy than in healthy non-pregnant women (p < 0.001).


CONCLUSIONS
Under physiological conditions, human amniotic fluid was found to be enriched in P-IPG compared with maternal urine, suggesting a possible fetal origin. Therefore, IPGs may play a role in insulin sensitivity and fetal growth and, perhaps, be involved in some of its abnormalities such as macrosomia and intrauterine growth restriction.
Department of Molecular Pathology, Molecular Medicine Unit, Royal Free and University College Medical School, London, UK. marco.scioscia@tin.it
Marco
M
Scioscia
Antonella
A
Vimercati
Luigi E
LE
Selvaggi
Charles H
CH
Rodeck
Thomas W
TW
Rademacher
D000328:Adult; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000737:chemistry*; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007295:Inositol Phosphates / Q000032:analysis*; D011134:Polysaccharides / Q000032:analysis*; D011247:Pregnancy; D011446:Prospective Studies
D007295:Inositol Phosphates; D011134:Polysaccharides; C028039:inositol phosphate glycan