Expression Of HMGB1-RAGE Signaling Pathway In Placental Tissue And Peripheral Blood And Its Relationship With Preeclampsia

Objective:Preeclampsia(PE)is a pregnancy-specific disorder that is associated with gestational hypertension.PE is characterized by hypertension,proteinuria,and other systemic disorders at or after 20 weeks of gestation.Severe preeclampsia(sPE)is one of the leading causes of maternal and perinatal mortality.The exact mechanism of preeclampsia is unclear.Therefore,it is of great significance and value to explore its pathogenesis.At present,it is believed that mild inflammatory reaction will occur in the mother during normal pregnancy,which is conducive to normal pregnancy.However,excessive inflammatory reaction will disrupt the immune balance between the mother and the fetus,leading to the dysfunction of trophoblast cells and the restricted trophoblast cell migration.Inflammatory reaction is an important pathological basis for pre-eclampsia.High mobility group box 1(HMGB1)has been shown to play an important role as a pro-inflammatory cytokine in chronic inflammatory and immune-reactive diseases.HMGB1 is expressed in placental tissue and is locally elevated in placental inflammation.As a multifunctional protein,HMGB1 binds to cell surface receptors and causes inflammatory reactions through signal transduction.The receptor for advanced glycation end products(RAGE)is the main receptor for HMGB1.HMGB1 binds to RAGE and induces the activation of nuclear factor-kappa B(nuclear-?B,NF-?B),which stimulates secretion of TNF,IL-1,IL-6 and IL-8.The NF-kB family is a variety of inflammations.The upstream regulator of the relevant process.The expression of HMGB1 and its inflammatory response signaling pathway may be related to the pathogenesis of preeclampsia.This study was designed to detect the expression of HMGB1-RAGE inflammatory signaling pathway-related molecules in placenta and peripheral blood of preeclampsia patients,aiming to provide a basis for exploring the pathogenesis of preeclampsia.Methods1.Ninety-nine pregnant women who were hospitalized in the Department of Obstetrics,First Affiliated Hospital of Zhengzhou University from January 2017 to January 2018 were enrolled.According to the pre-eclampsia diagnosis and classification criteria,30 pregnant women in the mild and severe preeclampsia group were selected.Healthy pregnant women 30 cases,monitoring the blood pressure of three groups of pregnant women,and collecting the maternal and peripheral venous blood of three groups of pregnant women.2.The expression of HMGB1,RAGE,NF-Bp65 in peripheral blood of each group was detected by enzyme-linked immunosorbent assay(ELISA),and the correlation between the expression of HMGB1,RAGE,NF-Bp65 in peripheral blood and systolic blood pressure was analyzed.The expression of HMGB1,RAGE,NF-Bp65 protein and mRNA were detected by western blotting and fluorescence quantitative PCR.Immunohistochemistry method was used to measure the protein expression of HMGB1,RAGE and NF-?Bp65 protein.3.Statistical analysis was performed using SPSS21.0 statistical software.and all measurement data were expressed by?x±s.One-way ANOVA or ?2 test for comparison between groups.The LSD-t method was used for comparison.The correlation analysis was performed by Pearson test.P<0.05 was used as the difference.Statistical significance.Results1.ELISA showed that The levels of HMGB1,RAGE and NF-?Bp65 of serum in the mild and severe preeclampsia groups were significantly higher than that in the healthy pregnant women group(P<0.05).In addition,compared with the mild preeclampsia group,the levels of HMGB1 RAGE and NF-?Bp65 in the sever group was significantly higher(P<0.05).In addition,in preeclampsia group HMGB1?RAGE and NF-?Bp65 protein expression correlated positively with systolic blood pressure(r = 0.389,r = 0.550,r = 0.713,P<0.05).2.Real-time PCT showed that :compared with the mild preeclampsia group and the control group,the mRNA levels of HMGB1,RAGE and NF-?Bp65 in the severe preeclampsia group was significantly higher(P<0.05).3.Western blot was employed to confirm that HMGB1,RAGE and NF-?Bp65 protein level was elevated significantly in severe PE group(P<0.05).4.Positive immunostaining of HMGB1,RAGE and NF-?Bp65 was observed in the cytoplasm of cytotrophoblast,decidual cells and the placentas from the three groups.The positive rates of placenta in the mild and severe preeclampsia groups were significantly higher than that in the healthy pregnant women group(P<0.05).In addition,compared with the mild preeclampsia group,the positive rate of immunostaining of HMGB1,RAGE and NF-?Bp65 in the severe group was significantly higher(P<0.05).5.Correlation analysis: Serum HMGB1,RAGE and NF-?Bp65were positively correlated in the preeclampsia group: HMGB1 and RAGE were positively correlated in the mild preeclampsia group(r=0.385,P<0.05);HMGB1 and NF-?Bp65(r=0.277,P<0.05),RAGE and NF-?Bp65(r=0.263,P<0.05),in severe preeclampsia group HMGB1 and RAGE(r=0.741,P<0.05);HMGB1 and NF-?Bp65(r=0.546,P<0.05).RAGE and NF-?Bp65r=0.325,P<0.05).There was a positive correlation between HMGB1,RAGE and NF-?Bp65mRNA expression in placental tissues of pregnant women in the preeclampsia group: HMGB1 and RAGE in the mild preeclampsia group(r=0.485,P<0.05);HMGB1 and NF-?Bp65(r=0.261,P<0.05),RAGE and NF-?Bp65(r=0.468,P<0.05).HMGB1 and RAGE in severe preeclampsia group(r=0.503,P<0.05);HMGB1 and NF-?Bp65(r=0.728,P<0.05),RAGE and NF-?Bp65(r=0.656,P<0.05).In the control group,there was no significant correlation between the above indicators(P>0.05).Conclusion1.The expression site of HMGB1 in normal pregnant placenta is different from that in preeclampsia placenta,and there is obvious karyoplasmic metastasis,which may be involved in the pathogenesis of preeclampsia.2.HMGB1,RAGE and NF-Bp65 were significantly increased and positively correlated in placental tissues of preeclampsia patients,suggesting that there was positive feedback between HMGB1,RAGE and NF-Bp65 signaling pathways,aggravating the progress of preeclampsia.3.HMGB1,RAGE and NF-Bp65 are highly expressed in peripheral blood of preeclampsia patients and positively correlated with systolic blood pressure,suggesting that HMGB1,RAGE and NF-Bp65 act on maternal vascular system,damage endothelial cell function and cause hypertension.HMGB1 may be a serological molecular marker of severe preeclampsia,indicating the development of preeclampsia.