lipidomic data of pig endometrium during late gestation

Limiting the level of piglet losses before weaning is a growing demand from producers and society to improve the welfare and health of sows and piglets. In particular, perinatal mortality, which can be defined as the complete development allowing survival at birth, is mostly due to reduced piglet maturity that occurs at the end of gestation. Fetal growth and maturation depend on a fine balance between the nutrient requirements for optimal fetal growth and the maternal nutrient requirements. This balance occurs at the feto-maternal interface, defined as the interaction between the mother (uterus/endometrium) and the fetus (placenta). Thus, the CO-LOCATION project (ANR20-CE20-0020-01) studies the feto-maternal system in relation to fetal maturation and piglet survival at birth. To this end, we documented the lipidome of endometrial tissue in late gestation from two breeds with extreme fetal maturity: Large White and Meishan, showing substantial and low neonatal mortality, respectively. the sows were inseminated with mixed semen from both breeds (LW+MS boars), producing pure and reciprocal crossbred fetuses. 187 endometrial samples were selected from the PORCINET tissue collection (ANR-09-GENM-005) together with sow breed, day of gestation, sex, fetal genotypes. The 187 samples of endometrium were pulverized under liquid nitrogen using a MM400 Mixer Mill (Retsch, Haan, Germany) and randomized for multiple effects: DG, MG, fetal genotype and fetal sex to avoid technical bias. For each sample,100 mg of frozen powder was collected under liquid nitrogen in a 2ml FastPrep tube containing Lysing Matrix S (MP biomedicals, Irvine,CA, USA). The extraction was performed on ice using methanol, water and dichloromethane. The tubes were centrifuged at 2,870 g at 4°C for 15 minutes. The upper aqueous phase containing hydrophilic compounds were collected for metabolomic analysis .The lower organic phase, containing hydrophobic compounds was was analysed for nine neutral lipids by gas chromatography coupled to a Flame-Ionization Detector (GC-FID). The quantifications of the nine neutral lipids (L-Cholesterol, L-Cholesterol C16, L-Cholesterol C18, L-Cholesterol C20 and five triglycerides (TAG): TAG48, TAG50, TAG52, TAG54, TAG56) were expressed relative to the internal standard specific to each class and then normalized by tissue weight. L-Cholesterol C20 and TAG48 were not detected in the endometrium with this method.