Expression Of Bcl-xL And Bcl-xS In Decidua And Chorionic Villi With Unexplained Recurrent Spontaneous Abortion

Objectives:To investigate the expression of Bcl-xL and Bcl-xS in decidua and chorionic villi with unexplained recurrent spontaneous abortion and to evaluate the association between unexplained recurrent spontaneous abortion and abnormal apoptosis.Methods:27cases of decidua with unexplained recurrent spontaneous abortion and27cases with normal pregnancy,22patients with unexplained recurrent spontaneous abortion villi and22cases with normal pregnancy were collected aseptically. The protein expression and location of Bcl-xL/Bcl-xS were detected by immunohistochemistry. The mRNA and protein levels of Bcl-xL/Bcl-xS were detected by RT-PCR and western blotting respectively.Results:(1) Bcl-xL and Bcl-xS were expressed in the cytoplasm of decidual cells, villous syncytiotrophoblast and trophoblastic cells. Compared with the control group, the expression levels of Bcl-xL protein in decidua and chorionic villi with unexplained recurrent spontaneous abortion decreased while Bcl-xS increased.(2) Compared with the control group, the mRNA levels of Bcl-xL in decidua and chorionic villi with unexplained recurrent spontaneous abortion were significantly decreased while Bcl-xS significantly increased (P<0.05).(3) Compared with the control group, the protein levels of Bcl-xL in decidua and chorionic villi with unexplained recurrent spontaneous abortion significantly decreased while Bcl-xS significantly increased (P<0.05). Conclusion:Compared with tissue from normal pregnance, the expression levels of Bcl-xL in decidua and chorionic villi with unexplained recurrent miscarriage decreased, while pro-apoptotic Bcl-xS increased, which indicated that abnormal apoptosis had a correlation with unexplained recurrent abortion, and excessive apoptosis may be one of the mechanisms of unexplained recurrent abortion. Bcl-xL and Bcl-xS in this study come from the same gene locus. Alternative splicing for these key genes of apoptosis may be one of the important mechanism for unexplained recurrent spontaneous abortion.