Expression Of Sphingosine-1-Phosphate Phosphatases 1 In Mouse Uterus During Early Pregnancy

Sphingosine 1-phosphate(S1P)is a bioactive lipid whose levels are tightly regulated by its synthesis and degradation.Intracellularly,SlP is dephosphorylated by the actions of sphingosine-1-phosphate phosphatases(SPP).SPP1 has been shown to regulate apoptosis by elevating ceramide levels,ER-to-Golgi ceramide trafficking,and autophagy induced by ER stress.During implantation,the embryo and uterus undergo synchronous development and communication,and is associated with apoptosis.In this study,we established early pregnancy model,pseudopregnancy model,delayed implantation and activated implantationmodel,artificial decidualization model in mice.The expression of SPP1 protein in uterus tissue of each model was detected by immunohistochemistry,and the protein expression index of SPP1 protein in early pregnancy uterus tissue was detected by Western blot.The immunohistochemistry results showed that SPP1 protein was mainly expression in the luminal epithelium and glandular epithelium on days 1 to 4 of pregnancy.On day 5 of pregnancy,SPP1 protein immunostaining signal was also observed in the subluminal stroma immediately surrounding the implanted blastocyst.On days 6 to 8,SPP1 protein signal is mainly expressed in the decidua,and the scope of expression gradually expandedthe.Immunohistochemistry results showed that SPP1 protein was mainly expression in the luminal epithelium and glandular epithelium of pseudopregnancy.The tendency of the expression pattern was similar to that observed on days 1 to 4 of pregnancy.The immunohistochemistry results showed that there was SPP1 protein expression in the LE and GE under delayed implantation conditions.After delayed implantation was terminated by estrogen treatment and embryos were implanted,SPP1 protein signal was observed in the LE and stroma around the implanted blastocyst.In artificial decidualization models,SPP1 protein expressed mainly in decidual zone and the weakly expression was found in the luminal epithelium in the control.Western Blot showed that the expression of SPP1 protein showed regular changes on 5 to 8 days of pregnancy.In summary,the expression of SPP1 protein in the uterine tissues of early pregnancy in mice has specific changes in time and space.This indicated that SPP1 protein was related to embryo implantation process and played a role in mouse decidualization.