Expression of endoglin and transforming growth factor-β1 in placenta and superficial myometrium of women with gestational hypertension or preeclampsia

Abstract

Objective To investigate the expression of transforming growth factor-β1 (TGF-β1),endoglin (Eng) and their mRNA in placenta and superficial myometrium of patients with gestational hypertension or preeclampsia and to explore the role of Eng and TGF-β1 in the pathogenesis of gestational hypertension or preeclampsia.Methods One hundred and ten pregnant women were selected in the Second Affiliated Hospital of Tianjin Medical University from April 2009 to April 2010 who underwent cesarean sections and were divided into four groups:gestational hypertension group (n=30),mild preeclampsia group (n=30),severe preeclampsia group (n=30) and control group (normal pregnant women without labor and perinatal complications,n=20).The tissues of placenta and superficial myometrium were collected during cesarean section.Protein levels of Eng and TGF-β1 were detected by Western Blot.Real-time fluorescence reverse transcription polymerase chain reaction was used to detect the Eng and TGF-β1 mRNA expression.One-way ANOVA was used to compare among groups,Student-Newman-Keuls test was used to compare the differences between groups; relation between groups was analyzed by Pearson relation and linear regression.Results In control group,gestational hypertension group,mild and severe preeclampsia group,the Eng mRNA level was 1.00,1.27±0.58,1.54±0.41 and 1.83±0.35,and the TGF-β1 mRNA level was 1.00,1.64 ± 0.33,1.92± 0.38 and 2.23 ± 0.53 in placenta respectively; those figures changed to 1.00,1.32±0.46,1.59±0.37 and 1.93±0.52,and 1.00,1.71 ± 0.45,1.91 ± 0.51 and 2.37 ± 0.46 in superficial myometrium respectively.The Eng and TGF-β1 mRNA levels of control group were lower than those of the other three groups (P＜0.05).The higher the mRNA level,the more severe the disease (P＜ 0.05).In control group,gestational hypertension group,mild and severe preeclampsia group,the Eng protein expression was 0.11±0.07,0.15± 0.05,0.18 ± 0.06 and 0.43 ± 0.04,and the TGF-β1 protein expression was 0.11 ±0.02,0.26 ± 0.05,0.27± 0.03 and 0.88 ± 0.09 in placenta respectively; those figures changed to 0.14±0.06,0.16±0.04,0.20±0.08 and 0.46±0.05,and 0.15±0.03,0.29±0.06,0.31±0.04 and 0.91 ±0.08 in superficial myometrium respectively.The Eng and TGF-β1 protein levels of control group were lower than those of the other three groups (P＜0.05).The higher the protein level,the more severe the disease (P＜0.05).In the gestational hypertension group,mild and severe preeclampsia group,there were positive correlations between Eng and TGF-β1 protein levels in placenta (r=0.57,0.61 and 0.60 respectively,P＜0.05) and superficial myometrium (r=0.59,0.62 and 0.61 respectively,P ＜ 0.05).Conclusions Eng and TGF-β1 might play a role in pathogenesis of gestational hypertension and preeclampsia. Key words: Hypertension,pregnancy-induced; Placenta; Myometrium; Transforming growth factor beta 1; Antigens,CD; Receptors,cell surface