Lysophospholipid signaling in the function and pathology of the reproductive system

BACKGROUND: Lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) are two prominent signaling lysophospholipids (LPs) exerting their functions through a group of G protein-coupled receptors (GPCRs). This review covers current knowledge of the LP signaling in the function and pathology of the reproductive system. METHODS: PubMed was searched up to May 2008 for papers on lysophospholipids/LPA/S1P/LPC/SPC in combination with each part of the reproductive system, such astestis/ovary/ uterus. RESULTS: LPA and SIP are found in significant amounts in serum and other biological fluids. To date, 10 LP receptors have been identified, including LPA1-5 and S1P1-5. In vitro and in vivo studies from the past three decades have demonstrated or suggested the physiological functions of LP signaling in reproduction, such as spermatogenesis, male sexual function, ovarian function, fertilization, early embryo development, embryo spacing, implantation, decidualization, pregnancy maintenance and parturition, as well as pathological roles in ovary, cervix, mammary gland and prostate cancers. CONCLUSIONS: Receptor knock-out and other studies indicate tissue-specific and receptor-specific functions of LP signaling in reproduction. More comprehensive studies are required to define mechanisms of LP signaling and explore the potential use as a therapeutic target.