Effect of TCDD exposure on the expression of PR isoforms and DNMT-1 of eutopic endometrium in mice
ZHU Fang
CUI Zhaoling
HUANG Xianghua
Abstract：Objectives To investigate the influence of TCDD on the expression of PR isoforms ( PR-A and PR-B) and DNA methyltransferase-1 ( DNMT-1 ) of eutopic endometrium in mice , and to explore the methylation of CpG islands in the promoter region of PR-A and PR-B gene.Methods Sixty mice divided into 0/0,0/3,3/0,3/3,3/10 groups,with 12 female mice in each group.The mice in each group received TCDD (3μg/kg) again on the 49th day after birth except for the 0/0 group.On the 70th day after birth autotransplantation of endometrium was performed to establish the endometriosis models ,at the same time,the mice in each group were exposed to TCDD (3μg/kg) again except for 0/0 group.After the surgery the mice in exposure groups received TCDD (3μg/kg) respectively at 3,6,9 weeks.Finally,at 12 weeks after surgery the mice were executed,the the endomembrane in the position was entrapped with paraffin blocks ,and the expression levels of DNMT-1, PR-A were detected by immunohistochemistry(SP),moreover,the methylation of CpG islands in promoter region of PR-A and PR-B gene was detected by methylation-specific PCR(MSP).Results The expression levels of DNMT-1 in 3/3 group were significantly higher than those in 0/0 group( P <0.01),at the same time,which in 3/10 group were significantly higher than those in 3/3 group( P <0.01).However the expression levels of PR-B in 0/0 group were significantly higher than those in 3/3 group( P <0.01),which in 3/3 group were significantly higher than those in 3/10 group( P <0.01).But there were no significant differences in the expression levels of PR-A among different groups ( P >0.05).(2) The methylation degree of CpGs islands of PR-B gene in 3/3 group was significantly higher than that in 0/0 group( P <0.05),which in 3/10 group was significant higher than that in 3/3 group( P <0.05).However there was no significant difference in methylation degree of PR-A among different groups( P >0.05).Conclusion TCDD may enhance methylation degree of CpG islands in promoter of PR-B gene by up-regulating the expression of DNMT-1 to reduce the expression of PR-B of eutopic endometrium in mice ,as a result,which may promote the pathogenesis and development of endometriosis .
Keywords：endometriosisTCDDDNA methyltransferase-1PR-APR-B
Publication Date：2015-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 334-338 )