Lysophosphatidic Acid Signaling in Late Cleavage and Blastocyst Stage Bovine Embryos

[摘要] Lysophosphatidic acid (LPA) is a known cell signaling lipid mediator in reproductive tissues. In the cow, LPA is involved in luteal and early pregnancy maintenance. Here, we evaluated the presence and role of LPA in bovine early embryonic development. In relevant aspects, bovine embryos reflect more closely the scenario occurring in human embryos than the mouse model. Transcription of mRNA and protein expression of enzymes involved in LPA synthesis (ATX andcPLA2) and of LPA receptors (LPAR1–4) were detected in Days 5 and 8in vitroproduced embryos. Embryonic LPA production into culture medium was also detected at both stages of development. Supplementation of culture medium with LPA (10−5 M) between Days 2 and 8 had no effect on embryo yield and quality and on blastocyst relative mRNA abundance of genes involved in prostaglandin synthesis (PTGS2,PGES, andPGFS) and steroidogenesis (3βHSD). However, LPA treatment affected transcription levels of embryo quality markers, decreasingBAX(apoptotic) and increasingBCL2(antiapoptotic) andIGF2R(growth marker) gene transcription levels. Blastocyst transcription ofOCT4(pluripotency marker) was not affected by LPA stimulation. In conclusion, LPA is an early bovine embryonic autocrine/paracrine signaling mediator, and LPA action may be relevant in early embryo-maternal interactions leading to embryonic survival.

[学科分类] 生理学与病理学