Background: Early pregnancy failure has a profound impact on both human reproductive health and animal production. 2/3 pregnancy failures occur during the peri-implantation period; however, the underlying mechanism(...Background: Early pregnancy failure has a profound impact on both human reproductive health and animal production. 2/3 pregnancy failures occur during the peri-implantation period; however, the underlying mechanism(s) remains unclear. Well-organized modification of the endometrium to a receptive state is critical to establish pregnancy Aberrant endometrial modification during implantation is thought to be largely responsible for early pregnancy loss. Result: In this study, using well-managed recipient ewes that received embryo transfer as model, we compared the endometrial proteome between pregnant and non-pregnant ewes during implantation period. After embryo transfer, recipients were assigned as pregnant or non-pregnant ewes according to the presence or absence of an elongated conceptus at Day 17 of pregnancy. By comparing the endometrial proteomic profiles between pregnant and non-pregnant ewes, we identified 94 and 257 differentially expressed proteins (DEPs) in the endometrial caruncular and intercaruncular areas, respectively. Functional analysis showed that the DEPs were mainly associated with immune response, nutrient transport and utilization, as well as proteasome-mediated proteolysis. Conclusion: These analysis imply that dysfunction of these biological processes or pathways of DEP in the endometrium is highly associated with early pregnancy loss. In addition, many proteins that are essential for the establishment of pregnancy showed dysregulation in the endometrium of non-pregnant ewes. These proteins, as potential candidates, may contribute to early pregnancy loss.展开更多
Increasing evidence suggests that epigenetic dysfunction may influence the stability of normal pregnancy. The ten-eleven translocation (TET) family and 5-hydroxymethylcytosine (5-hmC) were found to be linked with ...Increasing evidence suggests that epigenetic dysfunction may influence the stability of normal pregnancy. The ten-eleven translocation (TET) family and 5-hydroxymethylcytosine (5-hmC) were found to be linked with epigenetic reprogramming. The present study aimed to examine the expression of the TET family and 5-hmC in the villi of human embryos and compared their expression between normal pregnancy and early pregnancy loss (EPL). Embryonic villi were collected from normal pregnant women (control) experiencing medical abortion and from EPL patients at gestation ages of 6, 7 and 8 weeks. The mRNAs of TET family were analysed using quantitative polymerase chain reaction (qPCR), and TET proteins using Western blotting and immunohistochemical analysis. The MethylFlashTM Kit was used to quantify the absolute amount of 5-methylcytosine (5-mC) and 5-hmC. Our results showed that the expression of the TETs and 5-hmC in the normal villus decreased with increasing gestational age. Immunohistochemistry revealed that the TET proteins were expressed in the cytoplasm of trophoblasts and their expression was the highest in the 6-week tissue samples, which was consistent with the qPCR and Western blot results. The expression of TET1, TET2, and TET3 was lower in the villi in EPL group than in normal pregnancy group (P〈0.05 for all). It was concluded that the TET family and 5-hmC are critical in epigenetic reprogramming of human embryo. The findings also suggest that a deficiency of TETs in the villus might be associated with human EPL.展开更多
基金supported by grants from the National High-Tech R&D Program (Nos.2011AA100303,2013AA102506)the National Key Technology R&D Program(Nos.2011BAD19B01,2011BAD19B03,2011BAD19B04)
文摘Background: Early pregnancy failure has a profound impact on both human reproductive health and animal production. 2/3 pregnancy failures occur during the peri-implantation period; however, the underlying mechanism(s) remains unclear. Well-organized modification of the endometrium to a receptive state is critical to establish pregnancy Aberrant endometrial modification during implantation is thought to be largely responsible for early pregnancy loss. Result: In this study, using well-managed recipient ewes that received embryo transfer as model, we compared the endometrial proteome between pregnant and non-pregnant ewes during implantation period. After embryo transfer, recipients were assigned as pregnant or non-pregnant ewes according to the presence or absence of an elongated conceptus at Day 17 of pregnancy. By comparing the endometrial proteomic profiles between pregnant and non-pregnant ewes, we identified 94 and 257 differentially expressed proteins (DEPs) in the endometrial caruncular and intercaruncular areas, respectively. Functional analysis showed that the DEPs were mainly associated with immune response, nutrient transport and utilization, as well as proteasome-mediated proteolysis. Conclusion: These analysis imply that dysfunction of these biological processes or pathways of DEP in the endometrium is highly associated with early pregnancy loss. In addition, many proteins that are essential for the establishment of pregnancy showed dysregulation in the endometrium of non-pregnant ewes. These proteins, as potential candidates, may contribute to early pregnancy loss.
基金This study was supported by National Natural Science Foundation of China (No. 81601280, No. 31371517), Foundation of Nanfang Hospital, Southern Medical University, and Science and Technology Project of Guangdong Province (No. 2013B051000086).
文摘Increasing evidence suggests that epigenetic dysfunction may influence the stability of normal pregnancy. The ten-eleven translocation (TET) family and 5-hydroxymethylcytosine (5-hmC) were found to be linked with epigenetic reprogramming. The present study aimed to examine the expression of the TET family and 5-hmC in the villi of human embryos and compared their expression between normal pregnancy and early pregnancy loss (EPL). Embryonic villi were collected from normal pregnant women (control) experiencing medical abortion and from EPL patients at gestation ages of 6, 7 and 8 weeks. The mRNAs of TET family were analysed using quantitative polymerase chain reaction (qPCR), and TET proteins using Western blotting and immunohistochemical analysis. The MethylFlashTM Kit was used to quantify the absolute amount of 5-methylcytosine (5-mC) and 5-hmC. Our results showed that the expression of the TETs and 5-hmC in the normal villus decreased with increasing gestational age. Immunohistochemistry revealed that the TET proteins were expressed in the cytoplasm of trophoblasts and their expression was the highest in the 6-week tissue samples, which was consistent with the qPCR and Western blot results. The expression of TET1, TET2, and TET3 was lower in the villi in EPL group than in normal pregnancy group (P〈0.05 for all). It was concluded that the TET family and 5-hmC are critical in epigenetic reprogramming of human embryo. The findings also suggest that a deficiency of TETs in the villus might be associated with human EPL.