Investigation of Phosphatidylcholine by MALDI Imaging Mass Spectrometry in Normal and IVF Early-Stage Embryos.

ABSTRACT

The receptive phase of the uterus is marked by structural and functional maturation of the endometrium. During this limited time span, the blastocyst competency is superimposed on the receptive endometrium. It is a well-known fact that lipid signalling in early-stage pregnancy has a crucial role in successful embryogenesis. In our study, CD-1 mouse uteri after normal and in vitro fertilization (IVF) were investigated at 6.5, 8.5, and 10.5 days of pregnancy. Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry and liquid chromatography coupled tandem mass spectrometry were used for identification of phosphatidylcholine (PC) lipid structures. In the embryonal tissues, PC 320 and PC 340 were increased, while in the antemesometrial (AM) decidua the two 204-containing PCs, PC 364 and PC 384 were increased. In transferred uterus samples, higher expressions of PC 340, PC 341, PC 342, PC 361, and PC 362 in mesometrial decidua were seen, whereas the two 204-containing PCs, PC 364 and PC 384 showed increased expression in the AM and lateral decidua. This paper shows a significant spatio-temporal change in lipid metabolism during IVF procedures for the first time.