Phytosphingosine‐1‐phosphate (P1P) is a signaling sphingolipid that regulates various physiological activities. However, little is known about the effect of P1P in the context of reproduction. Thus, we aimed to investigate the influence of P1P on oocyte maturation during porcine in vitro maturation (IVM). Here, we report the expression of S1PR1–3 among P1P receptors (S1PR1–4) in cumulus cells and oocytes. When P1P was administered at concentrations of 10, 50, 100, and 1,000 nM during IVM, the metaphase II rate was significantly increased in the 1,000 nM (1 μM) P1P treatment group. Maturation rate improvement by P1P supplementation was observed only in the presence of epidermal growth factor (EGF). Oocytes under the influence of P1P showed decreased intracellular reactive oxygen species levels but no significant differences in glutathione levels. In our molecular studies, P1P treatment upregulated gene expression involved in cumulus expansion (Has2 and EGF), antioxidant enzymes (SOD3 and Cat), and developmental competence (Oct4) while activating extracellular signal‐regulated kinase1/2 and Akt signaling. P1P treatment also influenced oocyte survival by shifting the ratio of Bcl‐2 to Bax while inactivating JNK signaling. We further demonstrated that oocytes matured with P1P displayed significantly higher developmental competence (cleavage and blastocyst [BL] formation rate) and greater BL quality (total cell number and the ratio of apoptotic cells) when activated via parthenogenetic activation (PA) and in vitro fertilization. Despite the low levels of endogenous P1P found in animals, exogenous P1P influenced animal reproduction, as shown by increased porcine oocyte maturation as well as preimplantation embryo development. This study and its findings are potentially relevant for both human and animal‐assisted reproduction.

Phytosphingosine-1-Phosphate (P1P) is a signaling sphingolipid regulating various physiological activities. Yet, little is known of the effect of P1P in the context of reproduction. As such, we aimed to investigate the influence of P1P on oocyte maturation during porcine in vitro maturation (IVM). Here we report the expression of S1PR1-3 among P1P receptors (S1PR1-4) in cumulus cells and oocytes. When P1P was treated by concentrations 10 nM, 50 nM, 100 nM, and 1000 nM during IVM, Metaphase II rate was significantly increased in 1000 nM (=1 μM) P1P treatment group. Maturation rate improvement by P1P supplementation was only observed in the presence of EGF. Oocytes under the influence of P1P decreased intracellular ROS levels yet did not show significant differences in GSH levels. In our molecular studies, P1P treatment up-regulated gene expressions involved in cumulus expansion (Has2 and EGF), antioxidant enzyme (SOD3 and Cat), and developmental competence (Oct4) while activating ERK1/2 and Akt signaling. P1P treatment also influenced oocyte survival by shifting the ratio of Bcl-2 to Bax, while inactivating JNK signaling. We further demonstrated that oocytes matured with P1P significantly displayed not only higher developmental competence (cleavage and blastocyst formation rate), but also greater blastocyst quality (total cell number and the ratio of apoptotic cells) when activated via parthenogenetic activation (PA) and in vitro fertilization (IVF). Despite low levels of endogenous P1P found in animals, exogenous P1P was able to influence animal reproduction as shown by increased porcine oocyte maturation as well as preimplantation embryo development.