Serum biomarkers combined with uterine artery Doppler in prediction of preeclampsia

Maternal Serum Activin A, Inhibin A and Follistatin-Related Proteins across Preeclampsia: Insights into Their Role in Pathogenesis and Prediction

BACKGROUND

Within the endocrine-paracrine signalling network at the maternal-foetal interface, the activin-inhibin-follistatin system modulates extravillous trophoblast invasion, suggesting a potential role in preeclampsia pathogenesis. This study aimed to compile the evidence published in the last decade regarding the variation in maternal serum activins, inhibin- and follistatin-related proteins in preeclamptic pregnancies compared to healthy pregnancies, and to discuss their role in predicting and understanding the pathophysiology of preeclampsia.

MATERIAL AND METHODS

A scoping review was conducted in MEDLINE, EMBASE and LILACS databases to identify studies published within the last ten years (2012-2022).

RESULTS

Thirty studies were included. None of the studies addressed maternal serum changes of isoforms different from activin A, inhibin A, follistatin, and follistatin-like 3. Sixteen studies evaluated the potential of these isoforms in predicting preeclampsia through the area under the curve from a receiver operating characteristic curve.

CONCLUSIONS

In preeclampsia, inhibin A is upregulated in all trimesters, whereas activin A increases exclusively in the late second and third trimesters. Serum follistatin levels are reduced in women with preeclampsia during the late second and third trimesters. However, changes in follistatin-like 3 remain inconclusive. Inhibin A and activin A can potentially serve as biomarkers of early-onset preeclampsia based on the outcomes of the receiver operating characteristic curve analysis. Further investigations are encouraged to explore the feasibility of quantifying maternal serum levels of activin A and inhibin A as a clinical tool in early preeclampsia prediction.

Analysis of serum placental growth factor levels in preeclamptic and normotensive pregnant women in Lagos, Nigeria: a worthwhile screening tool?

The clinical usefulness of serum placental growth factor (PlGF) as a predictive biomarker of preeclampsia is currently being examined. However, there are still conflicting results in the literature. We assessed the association between maternal low PlGF levels and the occurrence and severity of preeclampsia. This was an analytical cross-sectional study conducted among 60 women with preeclampsia, and an equal number of matched normotensive pregnant women. PlGF concentrations were analysed using the ELISA method. Bivariate and multivariate analysis was used to test for the association between low maternal PlGF levels and the occurrence of preeclampsia and its severity. Statistical significance was reported at p < .05. The study showed that having a low maternal PlGF level (Adjusted OR 14.23; 95%CI 8.06, 29.71) together with being primigravid (Adjusted OR 3.97; 95%CI 1.03, 6.18) and having an unbooked pregnancy (Adjusted OR 8.07; 95%CI 2.06, 19.40) were independently associated with preeclampsia. We established an association between low maternal PlGF levels and preeclampsia, but no similar association with severe preeclampsia. The use of PlGF as a potential predictive marker and a reliable screening tool may have a profound implication on the prevention of preeclampsia and the subsequent reduction in its associated morbidity and mortality.Impact statementWhat is already known on this subject? The utility of serum placental growth factor (PlGF) as a predictive biomarker of preeclampsia is currently being examined, however, there are conflicting results of its clinical usefulness in the literature.What do the results of this study add? This study that assessed the association between maternal low PlGF levels and the occurrence and severity of preeclampsia showed that having a low maternal PlGF level together with being primigravid and having an unbooked pregnancy were independently associated with the occurrence of preeclampsia. However, we were unable to establish any significant relationship between maternal PlGF and the severity of preeclampsia.What are the implications of these findings for clinical practice and/or further research? We opined that the use of PlGF as a potential predictive marker and a reliable screening tool may have a profound clinical implication on the prevention and reduction in the associated morbidity and mortality of preeclampsia. However, there is an urgent need for more robust longitudinal studies to define the regulation of placental vascular development and the clinical usefulness of maternal serum PlGF and other placental biomarkers as potential screening tools for preeclampsia among black African women.

Role of Maternal Uterine Artery Doppler Versus Serum β-hCG During the First Trimester in the Prediction of Preeclampsia and IUGR

Objective:

Preeclampsia accounts for 15% of maternal deaths and may cause fetal morbidity and mortality. The aim of this research was to evaluate the efficacy of maternal uterine artery Doppler versus serum beta-human chorionic gonadotropin (β-hCG), during the first trimester, in predicting preeclampsia and intrauterine growth restriction (IUGR).

Materials and Methods:

In a convenient sample of 388 pregnant women, uterine artery resistive index (RI) and pulsatility index (PI) were assessed, and serum β-hCG level was measured at 11 to 13 weeks of gestation. The patients’ maternal blood pressure and fetal growth were monitored.

Results:

The patients with preeclampsia (n = 58) showed a significant uterine RI and PI increase with a significant β-hCG decrease compared with the normotensive patients (n = 330). The specificity of uterine PI and RI to predict preeclampsia and IUGR is higher than that of β-hCG. However, the sensitivity of combined diagnostic tools is higher than the singular use of these diagnostic tests.

Conclusion:

Uterine artery Doppler may be better than serum β-hCG in predicting preeclampsia and IUGR. However, combined diagnostic techniques may be better to screen at-risk patients.

Serum and urine levels of activin A in primigravidae and multigravidae: a prospective cross-sectional study

The aim of the present study was to investigate serum and urine levels of activin A in different moments of gestation, in primigravidae and in multigravidae, to understand whether these variables (biological sample and first gestation) affect activin A as a biomarker in pregnancy. We prospectively included 43 pairs of serum and urine samples from 25 women examined at different gestational ages (range 45 to 268 days). In the group of primigravidae (n = 16 samples from 9 participants), there was no significant change in serum activin A levels across gestation. Conversely, the group of multigravidae (n = 27 samples from 16 women) had higher serum activin A levels in the third trimester (2676 ± 840 pg/ml) compared to the first (583 ± 408 pg/ml) and second (1040 ± 384) trimesters (p = .025). Urine activin A concentrations did not differ between the two groups and did not change according to the gestation phase. There was no correlation between serum and urinary levels of activin A (r = 0.149, p = .359). These data suggest that activin A secretion may vary less during the first pregnancy, while urine activin A is unlikely to be a surrogate for the systemic levels of this hormone in pregnant women.

New Frontiers in Placenta Tissue Imaging

The placenta is a highly vascularized organ with unique structural and metabolic complexities. As the primary conduit of fetal support, the placenta mediates transport of oxygen, nutrients, and waste between maternal and fetal blood. Thus, normal placenta anatomy and physiology is absolutely required for maintenance of maternal and fetal health during pregnancy. Moreover, impaired placental health can negatively impact offspring growth trajectories as well as increase the risk of maternal cardiovascular disease later in life. Despite these crucial roles for the placenta, placental disorders, such as preeclampsia, intrauterine growth restriction (IUGR), and preterm birth, remain incompletely understood. Effective noninvasive imaging and image analysis are needed to advance the obstetrician's clinical reasoning toolkit and improve the utility of the placenta in interpreting maternal and fetal health trajectories. Current paradigms in placental imaging and image analysis aim to improve the traditional imaging techniques that may be time-consuming, costly, or invasive. In concert with conventional clinical approaches such as ultrasound (US), advanced imaging modalities can provide insightful information on the structure of placental tissues. Herein we discuss such imaging modalities, their specific applications in structural, vascular, and metabolic analysis of placental health, and emerging frontiers in image analysis research in both preclinical and clinical contexts.

The transforming growth factor β superfamily as possible biomarkers of preeclampsia: a comprehensive review

The etiology of preeclampsia - an abnormal placentation-mediated disease - is not fully understood; and there are very few biomarkers with which to predict and diagnose it. Early prediction and diagnosis of this pathology can lead to a significant improvement in maternal and perinatal outcomes. Since members of the transforming growth factor β superfamily influence placentation, and are released from the placenta into the maternal circulatory system, several studies have investigated the involvement of these cytokines in preeclampsia and the possibility of using their serum levels as biomarkers of the disease. In this review, we have summarized the reported relationships between the levels of this superfamily of cytokines and preeclampsia. The available information indicates that altered levels of some of these cytokines are involved in the pathogenesis and pathophysiology of preeclampsia, suggesting their likelihood of serving as predictive and diagnostic biomarkers of the disease.

Gene expression analysis of MMPs in women with preeclampsia using cell-free fetal RNA in maternal plasma

OBJECTIVE

Nucleic acids released from the placenta into the mother's blood circulation system provide a valuable source of potential biomarkers for early detection of pregnancy complications such as preeclampsia (PE). PE affects nearly 5-10% of pregnancies worldwide and is a major contributor to the maternal and neonatal mortality and morbidity. It is known that altered placental expression of matrix metalloproteinases (MMPs) may cause shallow cytotrophoblastic invasion and ultimately lead to preeclampsia. The present study aimed to evaluate pattern of placental/fetal expression of the MMP family (MMP-2, MMP-9, MMP-14, MMP-15 and MMP-26) in preeclamptic women and compare it to normal pregnancies, using cell free fetal RNA (cff-RNA).

METHODS

Blood samples were obtained from 20 pregnant women diagnosed with severe PE (28-32 weeks) and 40 control healthy pregnant women in two groups of either matched gestational age (N = 20) or 14 and 28 weeks pregnancies (each 10). cff-RNA was extracted from plasma, followed by reverse transcription of cff-RNA. Expression of MMP genes was measured using quantitative reverse transcription PCR (qRT-PCR).

RESULTS

The expression levels of MMP-2, MMP-9 and MMP-15 were significantly increased, while MMP-14 expression level was significantly reduced and the expression of MMP-26 showed a relative increase in PE pregnancies compared to the control group. Additionally, increased level of MMPs expression was observed by comparing 14 and 28 weeks gestation age in normal pregnancy.

CONCLUSION

Using cff-RNA, circulatory expression level of MMP-2, MMP-9, MMP-14 and MMP-15 were significantly altered in preeclampsia compared to normal pregnancies.

First trimester Doppler velocimetry of the uterine artery ipsilateral to the placenta improves ability to predict early-onset preeclampsia

This study sought to investigate the effects of placental laterality on the measurements of uterine artery (UtA) Doppler velocimetry and their application in predicting early-onset preeclampsia (PE).We conducted a prospective cohort study on all women with singleton, uncomplicated pregnancies scheduled for first-trimester nuchal translucency at our institution. Pulsatility index (PI) for both UtAs was measured by Doppler velocimetry, and placental laterality was determined. Additionally, pregnancy outcome data were abstracted from the medical records. Receiver operating characteristic curves (ROCs) were plotted.Of the 304 patients enrolled, 247 met the inclusion criteria. Among these patients, 240 had uncomplicated delivery, while 7 had early delivery at <34 weeks due to PE. For the uncomplicated pregnancies, PI measurements of the UtA ipsilateral to the placenta were similar (left versus right UtA: 1.06 ± 0.38 vs. 1.04 ± 0.40; P = .745). However, PI measurements of the UtA contralateral to the placenta differed significantly (left versus right UtA: 1.45 ± 0.51 vs. 1.3 ± 0.47; P = .027). In predicting early-onset PE, the ideal cut-off value for the placental side PI was 1.91, with sensitivity 100% and specificity 96.3%. For nonplacental side PI, the ideal cut-off value for PI was 1.975, with sensitivity 57.1% and specificity 79.2%. Using the mean of the left and right UtA PI, the ideal cut-off value was 1.63, with sensitivity 100% and specificity 74.2%.ROC analysis confirmed that PI measurements of the UtA on the placental side were significantly lower than those on the contralateral side, PI measurements of the UtA ipsilateral to the placenta were similar.

Activin A in Mammalian Physiology

Activins are dimeric glycoproteins belonging to the transforming growth factor beta superfamily and resulting from the assembly of two beta subunits, which may also be combined with alpha subunits to form inhibins. Activins were discovered in 1986 following the isolation of inhibins from porcine follicular fluid, and were characterized as ovarian hormones that stimulate follicle stimulating hormone (FSH) release by the pituitary gland. In particular, activin A was shown to be the isoform of greater physiological importance in humans. The current understanding of activin A surpasses the reproductive system and allows its classification as a hormone, a growth factor, and a cytokine. In more than 30 yr of intense research, activin A was localized in female and male reproductive organs but also in other organs and systems as diverse as the brain, liver, lung, bone, and gut. Moreover, its roles include embryonic differentiation, trophoblast invasion of the uterine wall in early pregnancy, and fetal/neonate brain protection in hypoxic conditions. It is now recognized that activin A overexpression may be either cytostatic or mitogenic, depending on the cell type, with important implications for tumor biology. Activin A also regulates bone formation and regeneration, enhances joint inflammation in rheumatoid arthritis, and triggers pathogenic mechanisms in the respiratory system. In this 30-yr review, we analyze the evidence for physiological roles of activin A and the potential use of activin agonists and antagonists as therapeutic agents.

Biomarkers for diagnosis of pre-eclampsia and endometriosis

Gynecological disorders are leading public health problems in developing countries with substantial impact on women's quality of life. Significant proportion of maternal mortality and reproductive morbidity is attributed to misdiagnosis and mismanagement of pregnancy related lethal pathological conditions and affect women's health. Timely diagnosis is necessary to prevent maternal deaths and to manage complications. Biomarker development will create a wide window of opportunity for early diagnosis. This review discusses the current status of biomarkers and recent advances in 'omics' technology for early screening of endometriosis and pre-eclampsia because of significant global bioburden associated with these disorders. This review will also give baseline data for future biomarker development strategies.