Placental growth factor and soluble fms-like tyrosine kinase-1 are useful markers for the prediction of preeclampsia but not for small for gestational age neonates: a longitudinal study

Objective

To determine maternal serum concentrations of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) longitudinally in normal pregnancies, pregnancies that developed preeclampsia and pregnancies that deliver a small for gestational age (SGA) infant, in order to evaluate them as markers for the prediction of preeclampsia.

Study design

In this case–control study we included 12 singleton pregnancies that developed preeclampsia and 104 randomly selected singleton normal pregnancies. Fourteen of the normal pregnancies gave birth to an SGA infant. Blood samples and ultrasonographic data were collected during the 1st, 2nd and 3rd trimesters of pregnancy.

Results

In preeclamptic pregnancies, PlGF (pg/mL) (median; inter-quartile range) was significantly lower in the 2nd (208; 84–339) (p = 0.035) and in the 3rd trimester (202; 109–284) (p = 0.002) while sFlt-1 was significantly higher only in the 3rd trimester (2521; 2101–3041) (p = 0.011) compared to normal pregnancies (PlGF 2nd: 311; 243–440, PlGF 3rd: 780; 472–1037, sFlt-1 3rd: 1616; 1186–2220). In pregnancies with SGA infants, PlGF and sFlt-1 did not differ significantly from normal pregnancies in any trimester. The sFlt-1 to PlGF ratio was significantly higher in preeclamptic pregnancies than in normal pregnancies, in both the 2nd and 3rd trimesters. The relative difference and the slope of PlGF concentration between 1st and 2nd trimester were significantly reduced in preeclampsia compared to normal pregnancies. A logistic regression model with predictors BMI, 2nd trimester Doppler PI and relative difference of PlGF from the 1st to the 2nd trimester gave 46% sensitivity and 99% specificity for the prediction of preeclampsia, with a very high negative predictive value of 98.3%.

Conclusions

Our study confirms that maternal serum PlGF concentration is significantly lower, at least after 20th week, while sFlt-1 concentration is significantly higher in 3rd trimester, in pregnancies destined to develop preeclampsia. Pregnancies that gave birth to SGA infants do not have altered angiogenic factor concentrations throughout pregnancy. The relative difference of PlGF from the 1st to the 2nd trimester, uterine artery Doppler PI in the 2nd trimester and BMI are the most powerful markers for the prediction of preeclampsia.     

First Trimester Screening for Fetal Aneuploidies Using Placental Growth Factor: The Great Obstetrical Syndrome (GOS) Study

Objective

This study sought to estimate the ability of first trimester maternal serum placental growth factor (PlGF) to identify fetal aneuploidies.

A prospective cohort study on the prediction of the diagnosis-to-delivery time in preeclamptic pregnancies: should the sFlt-1/PlGF ratio be added to routine evaluations?

Purpose

To analyze the clinical and laboratory factors that potentially affect the diagnosis-to-delivery time in preeclamptic pregnancies.

Methods

In this cross-sectional study, we followed 24 early onset preeclampsia (E-PE) and 26 late-onset preeclampsia (L-PE) cases. Maternal serum samples were obtained at the time of diagnosis and stored at ??80 °C until ELISA analysis for soluble fms-like tyrosine kinase-1 (SFlt-1) and placental growth factor (PlGF) levels.

Results

The median follow-up duration was 68 (1–339) h in the E-PE group and 330 (7–1344) h in the L-PE group. Maternal mean arterial pressure (MAP) at hospitalization was the strongest variable, and the sFlt-1/PlGF ratio added significantly to the Cox regression model. In the E-PE cases, the median sFlt-1/PlGF ratio was significantly higher in the subgroup with a follow-up duration?>?48 h than in the subgroup of cases with a follow-up duration?≤?48 h (5109 vs. 2080; p?=?0.038), and none of the seven cases with an sFlt-1/PlGF ratio?≥?75th percentile delivered during the first 48 h. Neither the 24-h proteinuria nor the gestational age at diagnosis added to the predictive power of the MAP at hospitalization.

Conclusion

Incorporation of the sFlt-1/PlGF ratio to the routine evaluation of preeclamptic pregnancies may help in the prediction of progression and management planning.

     

Influence of the sFlt-1/PlGF ratio on clinical decision-making in women with suspected preeclampsia – the PreOS study protocol

Objective: To assess how routine clinical use of the Roche fully automated Elecsys® sFlt-1/PlGF test changes decision-making of physicians to hospitalize pregnant women with suspected preeclampsia. Methods: The Preeclampsia Open Study (PreOS) study is a multicenter, prospective, open-label, non-interventional study in 150 women showing signs and symptoms of preeclampsia (suspected preeclampsia). Physicians record their intended procedures before and after knowledge of participants’ sFlt-1/PlGF ratio. The study is conducted at five investigational sites in Germany and Austria. Conclusion: The PreOS study will provide evidence on how sFlt-1/PlGF ratio testing influences clinical decision-making in women with suspected preeclampsia in real-world clinical practice.     

sFlt-1/PlGF ratio as a prognostic marker of adverse outcomes in women with early-onset preeclampsia

Soluble fms-like tyrosine kinase 1 (sFlt-1) is an anti-angiogenic factor released in higher amounts by preeclamptic placentas and it has been implicated in the endothelial dysfunction observed in the disease. In this study we evaluated if circulating sFlt-1/PlGF ratio is useful to predict adverse outcomes in women with early-onset preeclampsia. This is a cohort study of 88 preeclamptic women with singleton pregnancies at ?35 weeks of gestation. According to definitions used, adverse outcomes occurred in 46.5% (N = 43) of the patients. The median sFlt1/PlGF ratio (25th–75th centile) for all patients evaluated was of 42.26 (13.1–226.1). The median sFlt-1/PlGF ratio among women who had any adverse outcome (N = 43) versus no adverse outcomes (N = 45) was of 227.6 (80.3–346.1) versus 14.4 (3.35–30.0), (P < 0.0001). According to our analyses a sFlt-1/PlGF ratio cut-point of ?85 gave a sensitivity of 74.0% and specificity of 97.0%. The positive predictive value and the negative predictive value were 96.0% and 80.0%, respectively. The median sFlt-1/PlGF ratio (25th–75th centile) for patients who delivered within <7 days was 260.0 (127.7–404.7) as compared to 14.4 (3.35–34.97) for those patients who delivered within two weeks or more (P < 0.0001). Our results suggest that sFlt-1/PlGF ratio is a promising marker for adverse outcomes in women with early-onset preeclampsia.     

Correlation between uterine artery Doppler and the sFlt-1/PlGF ratio in different phenotypes of placental dysfunction

Objective: To explore correlations between the sFlt-1/PlGF ratio and uterine arteries (UtA) Doppler indexes in placental dysfunction-related disorders (PDD).

Methods: We prospectively included women with a singleton pregnancy with preeclampsia (PE) only (n = 22), preeclampsia with fetal growth restriction (FGR) (n = 32), FGR only (n = 12), or normal pregnancy (n = 29).

Results: In PDDs, significantly positive correlations between the sFlt-1/PlGF ratio and the mean UtA pulsatility (mPI-UtA), as well as the resistance index (mRI-UtA) were found (p = 0.015, p = 0.019, respectively), but not in normal pregnancies. PDD with signs of impaired placentation, evidenced by the increased sFlt-1/PlGF ratio and mPI-UtA, was found in 50.0%, and, by the increased sFlt-1/PlGF ratio and mRI-UtA, in 65.2%. PDD without signs of impaired placentation, evidenced by the increased sFlt-1/PlGF ratio but normal mPI-UtA, was found in 24.2%, and, by the increased sFlt-1/PlGF ratio but normal mRI-UtA, in 7.6%. A substantial proportion of women with signs of impaired placentation were diagnosed with FGR with or without PE.

Conclusion: In PDD, the sFlt-1/PlGF ratio and UtA Doppler indexes increase proportionally. Correlations between the sFlt-1/PlGF ratio and UtA Doppler indexes might help to distinguish between PDDs with and without impaired placentation. However, further studies are needed to explore the correlations in different phenotypes of PDD.     

Placental expression of sFlt-1 and PlGF in early preeclampsia vs. early IUGR vs. age-matched healthy pregnancies

Objective: To investigate whether differences between early preeclampsia and early fetal growth restriction can be explained by differential placental expression patterns of sFlt-1, Flt-1, and PlGF. Methods: Placental tissues and maternal blood samples from six cases of preeclampsia, seven IUGR, and six age-matched controls were studied for mRNA and protein levels as well as protein localization and expression intensity. Results: Neither placental PlGF mRNA and protein expression nor placental villous trophoblast expression intensity of PlGF was altered by placental dysfunction. Conclusion: High sFlt-1 concentrations may account for diminished maternal serum PlGF levels.     

sFlt-1/PlGF ratio for the prediction of the time of delivery

Purpose

The soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) ratio has been shown to be a useful parameter for the diagnosis and prediction of preeclampsia (PE). An increased sFlt-1/PlGF ratio can be closely linked to the need to deliver. The aim of the study was to examine the mean time until delivery (MTUD) in pregnant women with a strongly increased sFlt-1/PlGF ratio.

Methods

From 2010 to 2018, the sFlt-1/PlGF ratio was determined in 995 singleton pregnancies with diagnosis or suspicion of PE/HELLP syndrome and/or intrauterine growth restriction (IUGR). MTUD of patients with a value above 655 in?<?34 weeks of gestation (group 1: n?=?13) and above 201 in?≥?34 weeks of gestation (group 2: n?=?15) was calculated. Patients with a value?>?85 but?<?655 in?<?34 weeks of gestation (group 3: n?=?70) and a value?>?110 but?<?201 (group 4: n?=?44) in?≥?34 weeks of gestation acted as controls.

Results

28 pregnant women with severely elevated sFlt-1/PlGF ratio and 114 controls were included. In group 1, MTUD was longer compared to group 2 without reaching statistical significance (96.7 h?±?132.2 vs. 47.7 h?±?44, p?=?0.222). In pregnancies?<?34 weeks of gestation (early onset), MTUD was significantly longer in group 3 compared to group 1 (361 h?±?317.3 vs. 96.7 h?±?132.2, p?<?0.001). In pregnancies?≥?34 weeks of gestation (late onset), MTUD was significantly longer in group 4 compared to group 2 (123.6 h?±?139.2 vs. 47.7 h?±?44, p?=?0.002).

Conclusions

The sFlt-1/PlGF ratio is suitable for decision-making regarding close monitoring of high-risk patients and need for lung maturation. However, for planning of delivery itself further prospective interventional studies are required to define its role as outcome predictor.

     

A comparison of the diagnostic utility of the sFlt-1/PlGF ratio versus PlGF alone for the detection of preeclampsia/HELLP syndrome

Objective: The Elecsys^® immunoassay sFlt-1/PlGF ratio and the Triage^® PlGF assay were compared (in a prospective, multicenter, case-control study) for diagnosis of preeclampsia/hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. Methods: Women in European perinatal care centers with singleton pregnancies were enrolled: 178 cases had confirmed preeclampsia and 391 controls had normal outcome. Patients in the preeclampsia/HELLP syndrome group were matched pairwise by gestational week to healthy controls (1:2). Maternal blood samples were analyzed using (a) fully automated Elecsys PlGF and Elecsys sFlt-1 immunoassays with two cutoffs (early-onset [<34 weeks] ≤33, ≥85; late-onset [≥34 weeks] ≤33, ≥110), and (b) Triage PlGF immunoassay (single cutoff). Diagnostic performance and utility were assessed. Results: Respectively, 83 and 95 women had early-onset or late-onset preeclampsia/HELLP syndrome. The overall diagnostic performance of the Elecsys immunoassay sFlt-1/PlGF ratio (area under the curve [AUC] 0.941) was higher than for Triage PlGF (AUC 0.917). The Elecsys immunoassay sFlt-1/PlGF ratio sensitivity and specificity was: 94.0% (95% confidence interval [CI] 86.5–98.0) and 99.4% (95% CI: 96.8–99.9) for early-onset preeclampsia; and 89.5% (95% CI: 81.5–94.8) and 95.4% (95% CI: 91.7–97.8) for late-onset preeclampsia. The Triage assay sensitivity and specificity was: 96.4% (95% CI: 89.8–99.3) and 88.5% (95% CI: 82.8–92.8) (early-onset); and 90.5% (95% CI: 83–96) and 64.5% (95% CI: 57.8–70.9) (late onset). Conclusions: The fully automated Elecsys immunoassay sFlt-1/PlGF ratio provides improved diagnostic utility over the Triage PlGF assay with improved specificity for the clinical management of pregnant women with suspected preeclampsia/HELLP syndrome.     

Prediction of preeclampsia with angiogenic biomarkers. Results from the prospective Odense Child Cohort

Objective: We aimed to investigate how maternal serum soluble Fms-like kinase 1 (sFlt-1), placental growth factor (PlGF), and sFlt-1/PlGF ratio prospectively associate to preeclampsia (PE) and clinical subtypes. Methods: In an unselected cohort of 1909 pregnant women, sFlt-1 and PlGF were measured with KRYPTOR assays in gestational weeks (GW) 8–14 and 20–34. Associations to PE were assessed by receiver operating characteristics and logistic regression. Results: Concentrations of sFlt-1, PlGF, and sFlt-1/PlGF in GW20-34 were predictive of PE development, but not in GW8-14. PlGF outperformed sFlt-1/PlGF ratio with an area under curve (AUC) of 0.755 vs. 0.704, p = 0.002. The highest AUC values for PlGF and sFlt-1/PlGF ratio were seen for severe early-onset PE (0.901 and 0.883). Negative predictive values were high for all PE types, but positive predictive values were low. Conclusion: PlGF and sFlt-1/PlGF had good predictive value for PE at GW20-34 in a population-based unselected cohort, however with low positive predictive value.     

Dual-cutoff of sFlt-1/PlGF ratio in the stratification of preeclampsia: a systematic review and meta-analysis

Purpose

To systematically review the approach of using two independent sFlt-1/PlGF cutoffs that has better sensitivity (cutoff-sen) and specificity (cutoff-spe) separately for risk stratification in the detection of preeclampsia.

Methods

PubMed and Embase databases and reference lists were searched up to June 2016. Inclusion criteria were blood samples for sFlt-1/PlGF with separate cutoffs (cutoff-sen and cutoff-spe) provided. Six relevant studies were identified. Pooling of results was done based on three studies and a systematic review was performed based on all six.

Results

The strategy of using a cutoff of ≤33 and ≥85 for early onset preeclampsia, and ≤33 and ≥110 for the late onset preeclampsia was proposed and examined. The pooled sensitivity for cutoff-sen was: 95.3% (90.6–98.1%) and 88.6% (82.9–92.9%) for early and late onset preeclampsia, respectively. The pooled specificity for cutoff-spe was: 97.6% (95.2–98.9%) and 94.2% (91.4–96.3%) for early and late onset preeclampsia respectively. The pooled estimation of the early onset pre-eclamptic pregnancies and control normal pregnancies classified in the equivocal zone was 4.9% (2.0–8.8%) and 32.4% (25.7–39.5%), respectively, and 26.8% (10.3–47.6%) and 8.7% (3.0–17.6%) for late onset patients.

Conclusion

The new dual-cutoff diagnostic system optimizes the predictive performance of the single cutoff system. Further studies are required to assess the performance of this system and to define the approach and frequency at which subjects in the equivocal zone should be screened.

     

Evaluation of agreement of placental growth factor (PlGF) tests and the soluble FMS-like tyrosine kinase 1 (sFlt-1)/PlGF ratio,comparison of predictive accuracy for pre-eclampsia,and relation to uterine artery Doppler and response to aspirin

Objectives: The objective of this study is to evaluate agreement between PlGF and sFlt-1/PlGF ratio tests and compare their predictive accuracy for pre-eclampsia in high-risk women. Also, to examine for associations of abnormal PlGF or sFlt-1/PlGF ratio with abnormal uterine artery Doppler and platelet response to aspirin.

Methods: Prospective cohort study, 150 pregnant women at high risk of pre-eclampsia prescribed 75?mg aspirin daily. Uterine artery Dopplers were assessed at 20⁺⁰–23⁺⁶ weeks. At 33⁺⁰–35⁺⁶ weeks platelet function aspirin metabolites, PlGF and the sFlt-1/PlGF ratio were measured.

Outcome: Measures were all pre-eclampsia and pre-eclampsia requiring delivery prior to 37 weeks.

Results: Overall percent agreement was 89.3% for PlGF tests but 74.7–78% for PlGF tests and the sFlt-1/PlGF ratio. AUCs were 0.70–0.75 for prediction of any pre-eclampsia and 0.92–0.99 for preterm pre-eclampsia. We found a significant association between abnormal PlGF or sFlt-1/PlGF ratio and abnormal uterine artery Doppler (χ² 5.47, p?=?.019), but no association with platelet response to aspirin (χ² 0.12, p?=?.913). There were no associations between suboptimal aspirin adherence and either abnormal angiogenic markers or uterine artery Dopplers (χ² 0.144, 0.038, p?=?.704, .846, respectively).

Conclusions: There was good agreement between PlGF tests and limited agreement between PlGF tests and the sFlt-1/PlGF ratio. All tests have heightened predictive accuracy for preterm pre-eclampsia. Abnormal PlGF or sFlt-1/PlGF ratio relates to abnormal uterine artery Doppler but not platelet response to aspirin.     

Association between the high soluble fms-like tyrosine kinase-1 to placental growth factor ratio and adverse outcomes in asymptomatic women with early-onset fetal growth restriction

Objective: To assess whether the high soluble fms-like tyrosine kinase-1 (sFlt-1) to placental growth factor (PlGF) ratio is associated with adverse outcomes (e.g., HELLP syndrome [hemolysis, elevated liver enzymes, and low platelets], severe hypertension uncontrolled by medication, non-reassuring fetal status, placental abruption, pulmonary edema, growth arrest, maternal death, or fetal death) and a shorter duration to delivery in early-onset fetal growth restriction (FGR).Methods: Thirty-four women with FGR diagnosed at <34.0 weeks were recruited. Serum angiogenic marker levels were estimated within 6 hours of a diagnosis of FGR. A receiver operating characteristic curve was used to determine the threshold of the sFlt-1/PlGF ratio to predict adverse outcomes. We used multivariable logistic regression analysis to examine the association between the sFlt-1/PlGF ratio and adverse outcomes. Finally, we used Kaplan-Meier analysis and the log-rank test to assess the probability of delay in delivery.

Results: Women who developed adverse outcomes within a week had a significantly higher sFlt-1/PlGF ratio than did those who did not develop complications. A cutoff value of 86.2 for the sFlt-1/PlGF ratio predicted adverse outcomes, with a sensitivity and specificity of 77.8% and 80.0%, respectively. Moreover, 58.4% of women with an sFlt-1/PlGF ratio ≥86.2 versus 9.1% of those with an sFlt-1/PlGF ratio <86.2 delivered within a week of presentation (p < 0.001). In multivariate analyses, an sFlt-1/PlGF ratio ≥86.2 (adjusted odds ratio 9.52; 95% confidence interval, 1.25–72.8) was associated with adverse maternal and neonatal outcomes.

Conclusion: A high sFlt-1/PlGF ratio was associated with adverse outcomes and a shorter duration to delivery in early-onset FGR.     

Impact of maternal serum levels of Visfatin,AFP, PAPP-A,sFlt-1 and PlGF at 11–13 weeks gestation on small for gestational age births

Objective: Investigating potential value of maternal serum Visfatin, sFlt-1, PlGF, AFP, PAPP-A levels at first trimester for prediction of small for gestational age (SGA) at birth.

Methods: Measurements were performed in 20 SGA and 65 control cases. Logistic regression analysis adjusted for age and weeks of pregnancy at data collection was performed to estimate odds ratios (OR), 95% confidence intervals (95% CI) and p values separately for each potential predictor. A multiple regression model was used to assess the impact of all the promising predictors adjusted for each other. Receiver operating characteristic (ROC) analysis was used to indicate the ability to discriminate between SGA cases and controls.

Results: There was an association of serum PlGF levels (OR 0.53 per interquartile range [IQR] increase in PlGF; 95% CI 0.24–1.16), sFlt-1/PlGF ratio (OR 1.42 per IQR increase in sFlt-1/PlGF; 95% CI 1.03–1.96), serum Visfatin levels (OR 0.31 per IQR increase in Visfatin; 95% CI 0.10–0.95) and smoking (OR 4.24; 95% CI 1.10–16.37) with SGA at birth.

Conclusions: Associations between SGA and lower PlGF, Visfatin levels as well as increased sFlt-1/PlGF ratio and smoking status were detected which may contribute to predict SGA.     

Nicotine and cotinine affect the release of vasoactive factors by trophoblast cells and human umbilical vein endothelial cells

Objective

To examine nicotine (N) and cotinine (C) effects on trophoblast cells (TCs) and human umbilical vein endothelial cells (HUVEC) secretion of soluble fms-like tyrosine kinase (sFlt-1), soluble endoglin (sENG), placental growth factor (PlGF), transforming growth factor-beta (TGF-beta) and vascular endothelial growth factor (VEGF).

Study design

Human placentas and umbilical cords were collected from uncomplicated pregnancies at term from a total of 24 non-smoking women with a history of normal blood pressure. TCs and HUVEC were cultured for 24 h with C or N (from 10⁻¹² to 10⁻⁷ M).

Main outcome measures

sFlt-1, sENG, PlGF, TGF-beta and VEGF release and messenger RNA (mRNA) expression were evaluated by ELISA and real-time polymerase chain reaction (PCR), respectively.

Results

N and C reduced sFlt-1, sENG and PlGF release by TCs and TGF-beta release by HUVEC. Conversely, N and C increased PlGF secretion, while N alone increased sFlt-1 release by HUVEC. N and C were able to modulate VEGF mRNA expression in HUVEC.

Conclusions

Our results suggest that N and C affect the balance of some important vasoactive factors released by TCs and HUVEC. This might be one of the possible mechanism through which smoke reduces the risk of hypertensive disorders during pregnancy as well as contributes to the well known detrimental effects of smoking on fetal development.     

Do the physiological aging of the placenta and the changes in angiogenesis marker sFlt-1 and PlGF concentrations predispose patients to late-onset preeclampsia?

Objective: Aging of the placenta is associated with natural processes that impair its functions. The processes are related to both oxidative stress exacerbation and the occurrence of higher concentrations of disordered angiogenesis markers. Both these types of processes are known to play roles in the development of preeclampsia. We attempted to show that natural ageing of the placenta can be one of the cofactors contributing to the development of late-onset preeclampsia.

Patients, materials and methods: 159 pregnant patients were divided into four groups: Two of preeclampsia patients and two of patients with physiological pregnancies, depending on the gestational age. For each group, disordered angiogenesis markers sFlt-1 and PlGF before and after 34 weeks of gestation and in particular stages of gestation were analyzed.

Results: Lower PlGF and sFlt-1/PlGF ratio values were found in cases of late-onset preeclampsia. In physiological pregnancies, sFlt-1 values were observed to increase and PlGF values to decrease with gestational age. An association was shown to exist between disordered angiogenesis markers and gestational age both in preeclampsia and physiological pregnancies.

Conclusions: (1) Analyses of disordered angiogenesis markers in early- and late-onset preeclampsia patients and patients with physiological pregnancies allow for a suggestion that natural “ageing of the placenta” and placental hypoperfusion lesions exacerbating with the advancing gestational age are some of the causes of late-onset preeclampsia. (2) Cases of early-onset preeclampsia are associated with more severe changes of disordered angiogenesis marker concentrations, which may be indicative of a more considerable impairment of placental perfusion in such patients. (3) In the course of the physiological pregnancy, there is a gradual increase in sFlt-1 and decrease in PlGF, which implies an elevated angiogenesis disorder that progresses with the gestational age.     

Effect of Pregnancy on the Management and Outcomes of Ovarian Torsion: A Population-Based Matched Cohort Study

Study Objective

To compare the treatment and surgical outcomes of ovarian torsion in pregnant and nonpregnant women.

Pain is an Independent Risk Factor for Failed Global Endometrial Ablation

Study Objective

To determine whether pain, as part of an indication for global endometrial ablation, is an independent risk factor for failure.

Spectrum of Neurological Complications in Eclampsia in a Tertiary Care Hospital in India

Objective

Preeclampsia or eclampsia is associated with significant maternal morbidity and mortality, and neurological complications are varied. This prospective observational study sought to collect data and push for early aggressive diagnostic evaluation for neurological complications in eclamptic women.

Edaravone inhibits hypoxia-induced trophoblast-soluble Fms-like tyrosine kinase 1 expression: A possible therapeutic approach to preeclampsia

Objective

To investigate the effects of edaravone, a potent free radical scavenger used clinically, on hypoxia-induced trophoblast-soluble Fms-like tyrosine kinase 1 (sFlt-1) expression.

Methods

A trophoblast cell line (HRT-8/SVneo) impaired by cobalt chloride (CoCl₂) was used as the cell model under hypoxic conditions. 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) was used to measure the viability of cells exposed to CoCl₂ and edaravone. The levels of intracellular reactive oxygen species (ROS) were analyzed by flow cytometry. mRNA expression of sFlt-1, vascular endothelial growth factor (VEGF), and placental growth factor (PlGF) in trophoblasts was measured by real-time polymerase chain reaction, and the secretion of sFlt-1, VEGF, and PlGF proteins was analyzed by enzyme-linked immunosorbent assays (ELISAs). A human umbilical vein endothelial cell (HUVEC) tube-formation assay was performed to identify the effects of CoCl₂ and edaravone on vascular development.

Results

CoCl₂ treatment caused the loss of trophoblast viability, the formation of ROS, and sFlt-1 mRNA and protein expression in a dose-dependent manner. Pretreatment with edaravone significantly inhibited hypoxia-induced oxidative stress formation and sFlt-1 expression in trophoblasts. Neither PlGF nor VEGF mRNA or protein expression was increased by CoCl₂. In the in vitro tube formation assay, edaravone showed a protective role in vascular development under hypoxic conditions.

Conclusion

This study demonstrated that hypoxia leading to increased sFlt-1 release in trophoblasts may contribute to the placental vascular formation abnormalities observed in preeclampsia and suggested that the free radical scavenger edaravone could be a candidate for the effective treatment of preeclampsia.