Maternal factors influencing metabolic programming of the blastocyst within the uterine environment

Abstract

It has been shown that maternal low protein diet in rodents confined to the pre-implantation period leads to reduced blastocyst lineage sizes and abnormal postnatal growth and physiology.  Here, we investigated the effect of maternal diet on the environment experienced by blastocyst.  Vaginal plug positive MF1 mice were fed either an 18% protein control diet or an is caloric 9% low protein diet (LPD) until day 2.5 3.5 or 4.5 of pregnancy whereupon uteri were dissected out and uterine luminal fluid collected by direct sampling.  Concentrations of the branch chain amino acids valine, leucine and isoleucine were significantly depleted on day 3.5 and 4.5 of pregnancy while methionine was elevated on day 4.5 in the uterine fluid of LPD mothers.  Luminal fluid glucose concentrations were not significantly altered in response to LPD.  These results suggest that programming may occur due to depletion of branched-chain amino acids in the uterine luminal fluids causing reduced signalling through the mTOR pathway thus causing embryos to undergo more catabolic rather than anabolic processes.

This study also measured amino acid levels in maternal serum on day 3.5 of pregnancy and observed the overall concentration of uterine fluid amino acids to be almost six times more than the maternal serum.  This suggests that active transport of amino acids is occurring across the uterine epithelium from serum to uterine fluid.  Furthermore, the branch chain amino acids leucine, isoleucine and valine were also significantly depleted in maternal serum and of a similar concentration to that found in uterine luminal fluid.  Unlike uterine luminal fluid glucose levels were found to be significantly elevated at day 3.5 of pregnancy and, the concentration of glucose in uterine luminal fluid was about half that of serum.  Serum insulin levels were significantly depleted at day 3.5 of pregnancy.

Uterine FGF-II levels were increased in response to LPD treatment.  This rise in uterine FGF-II levels could possibly aid implantation of the embryo.

More information

Identifiers

Catalogue record

Export record

ASCII CitationAtomBibTeXData Cite XMLDublin CoreDublin CoreEP3 XMLEndNoteHTML CitationHTML CitationHTML ListJSONMETSMODSMPEG-21 DIDLOpenURL ContextObjectOpenURL ContextObject in SpanRDF+N-TriplesRDF+N3RDF+XMLRIOXX2 XMLReferReference ManagerSimple Metadata