Association of pregnancy-associated plasma protein A polymorphism with preeclampsia - a pilot study

Pregnancy complications recur independently of maternal vascular malperfusion lesions

BACKGROUND

Spontaneous abortions, intrauterine growth restriction, and preeclampsia are thought to be caused by defective placentation and are associated with increased risk of adverse outcomes in subsequent pregnancies. However, it is not known whether the recurrence of adverse outcomes is associated with the recurrence of placental pathology. We hypothesized that recurrent maternal vascular malperfusion (MVM) underlies the recurrence of adverse outcomes.

METHODS

Using data from the National Collaborative Perinatal Project, we assessed the recurrence of pregnancy complications and MVM lesions (N = 3865), associations between a history of spontaneous abortions and MVM lesions or adverse outcomes in subsequent pregnancies (N = 8312), and whether the recurrence of pregnancy complications occurred independently of the presence of MVM lesions.

RESULTS

The odds of an MVM lesion were higher for a woman who had had an MVM lesion in a previous pregnancy (aOR = 1.6; 95% CI 1.3-1.9), although this was marginally non-significant after adjusting for covariates such as gestational age, race and BMI. The odds of preeclampsia, a small-for-gestational-age infant, premature delivery and early pregnancy loss were 2.7-5.0 times higher if there had been that same adverse outcome in a previous pregnancy. A history of spontaneous abortions was associated with higher risk of a small-for-gestational-age baby (aOR = 2.4; 95% CI 1.7-3.4) and prematurity (aOR = 5.1; 95% CI 2.3-11.5 for extremely preterm), but not preeclampsia. The recurrence of adverse outcomes was significant when restricting analyses to women without MVM lesions. Similarly, associations between adverse outcomes and previous spontaneous abortions were significant when statistically controlling for the presence of MVM lesions, or excluding pregnancies with MVM lesions.

CONCLUSIONS

Women with adverse outcomes in one pregnancy are at higher risk of complications in subsequent pregnancies. However, there is significant recurrence of adverse outcomes even in the absence of MVM.

Association of Low Maternal Pregnancy-associated Plasma Protein A with Adverse Perinatal Outcome

The aim is to provide an overall view of the association of low pregnancy-associated plasma protein A (PAPP-A) levels with adverse perinatal outcomes. The available literature in PubMed/Medline regarding PAPP-A and adverse pregnancy outcomes was searched for related articles, including terms such as “PAPP-A,” “intrauterine growth restriction (IUGR),” “small for gestational age (SGA),” “stillbirth,” “adverse outcome,” and others. The fifth percentile is supported by many recent studies to be PAPP-A’s cutoff for adverse outcome detection and the increased risk seems to be extremely high below 0.2 PAPP-A MoM (multiple of the median). Apart from chromosomal abnormalities, preeclampsia, intrauterine fetal demise, and pregnancy loss have been associated with maternal serum PAPP-A. For results below the first centile, PAPP-A has a strong positive predictive value for SGA and IUGR. Except for its vital role on the cleavage of insulin-like growth factor binding proteins (IGFBP), PAPP-A has proven to be a reliable marker for prenatal screening. Even though PAPP-A as a single predictor proved to be valuable for the prediction of some adverse perinatal outcomes, in some cases, a combination of PAPP-A to other maternal serum markers led to an increase in detection rates. PAPP-A is a promising maternal serum marker for pregnancy outcome prediction with more studies needed in order for its potentials to be fully understood and exploited.

Pregnancy-Associated Plasma Protein A2 in Hemodialysis Patients: Significance for Prognosis

BACKGROUND

Pregnancy-associated plasma protein A (PAPP-A) is associated with adverse outcome of long-term hemodialysis patients (HD). The aim of the study was to test whether its homolog pregnancy-associated plasma protein A2 (PAPP-A2) can be detected in serum of HD patients and to define its significance.

METHODS

The studied group consisted of 102 long-term HD patients and 25 healthy controls. HD patients were prospectively followed up for five years (2009-2014). PAPP-A2 was measured by surface plasmon resonance biosensor, PAPP-A by time resolved amplified cryptate emission.

RESULTS

PAPP-A2, similarly as PAPP-A, was significantly increased in HD patients (median (interquartile range)) PAPP-A2: 6.2 (2.6-10.8) ng/mL, vs. 3.0 (0.7-5.9) ng/mL, p=0.006; PAPP-A: 18.9 (14.3-23.4) mIU/L, vs. 9.5 (8.4-10.5) mIU/L, p<0.001). In HD patients, PAPP-A2 correlated weakly but significantly with PAPP-A (τ=0.193, p=0.004). Unlike PAPP-A, PAPP-A2 was not significant for prognosis of HD patients when tested alone. There was a significant interaction between PAPP-A and PAPP-A2 on the mortality due to infection of HD patients (p=0.008). If PAPP-A was below median, mortality due to infection was significantly higher for patients with PAPP-A2 values above median than for patients with low PAPP-A2 levels (p=0.011).

CONCLUSION

PAPP-A2 is increased in HD patients and interacts with PAPP-A on patients´ prognosis.

Effect of intrahepatic cholestasis of pregnancy on maternal serum screening tests

OBJECTIVE

In this study, we aimed to evaluate whether the changes in the first and second trimester maternal serum biochemical markers used for prenatal screening are associated with euploid pregnancies complicated by intrahepatic cholestasis of pregnancy (ICP).

METHODS

A total of 94 pregnant women were included in this retrospective comparative study. Thirty-seven women whose pregnancy was complicated with ICP constituted the study group whereas 57 of them constituted the control group. All hospital records were examined in terms of combined first trimester screening test and second trimester triple test parameters. Perinatal outcomes were also recorded.

RESULTS

No significant difference was observed between the two groups in term of age, BMI, and obstetric history (all p > 0.05). Mean serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and serum bile acid concentrations in the study group were significantly higher than in the controls (p < 0.001). There were no significant differences between the two groups in terms of first and second trimester serum biochemical markers. Newborn gender, route of birth, and NICU admission rates were also similar in the two groups. Mean birth weight of the control group was statistically significantly higher than the ICP group (p = 0.012).

CONCLUSION

We report no significant differences between pregnancies complicated by ICP and healthy pregnancies in terms of first and second trimester maternal serum screening test results.

Effect of pregnancy-associated plasma protein-A (PAPP-A) single-nucleotide polymorphisms on the level and activity of PAPP-A and the hormone profile in fluid from normal human small antral follicles

OBJECTIVE

To reveal a possible relationship between two single nucleotide polymorphisms (SNPs) in PAPP-A-1224 (rs7020782) and 327 (rs12375498)-and the level and activity of PAPP-A in follicular fluid (FF) of human small antral follicles, and to analyze the intrafollicular hormone levels.

DESIGN

Laboratory investigation.

SETTING

University hospital.

PATIENT(S)

Fifty volunteer women who contributed a total of 210 samples of FF from normal small antral follicles.

INTERVENTION(S)

Genotyping and measurement of antigen levels of steroids, PAPP-A, stanniocalcin-2 (STC2), and antimüllerian hormone (AMH) plus activity of PAPP-A toward insulin-like growth factor binding protein 4 (IGFBP-4).

MAIN OUTCOME MEASURE(S)

Measurement of PAPP-A levels and hormones with enzyme-linked immunosorbent assay (ELISA) and PAPP-A activity toward radiolabeled IGFBP-4.

RESULT(S)

Women homozygous for the minor C allele of the 1224 SNP showed a statistically significantly lower level of PAPP-A protein and activity in FF compared with women carrying the major A allele. These women also displayed nonsignificant reduced levels of estradiol and increased levels of AMH and androgen. A statistically significant correlation between FF levels of PAPP-A activity and the molar ratio of PAPP-A/STC2 was obtained. The 327 SNP did not show statistically significant associations.

CONCLUSION(S)

This study presents a statistically significant effect of the 1224 SNP on the level and activity of PAPP-A in human follicles, suggesting that the FF level of bioactive insulin-like growth factor depends on the genotype. We observed STC2 to be an important regulator of PAPP-A in human FF. The 1224 SNP has previously been associated with recurrent pregnancy loss, so further evaluation of an underlying mechanism including aberrant control of insulin-like growth factor activity is warranted.

Pregnancy-associated plasma protein A gene polymorphism in pregnant women with preeclampsia and intrauterine growth restriction

Preeclampsia (PE) and intrauterine growth restriction (IUGR) are still among the most commonly researched titles in perinatology. To shed light on their etiology, new prevention and treatment strategies are the major targets of studies. In this study, we aimed to investigate the relation between gene polymorphism of one of the products of trophoblasts, pregnancy-associated plasma protein A (PAPP-A) and PE/IUGR.A total of 147 women (IUGR, n = 61; PE, n = 47; IUGR + PE, n = 37; eclampsia, n = 2) were compared with 103 controls with respect to the sequencing of exon 14 of the PAPP-A gene to detect (rs7020782) polymorphism. Genotypes "AA" and "CC" were given in the event of A or C allele homozygosity and "AC" in A and C allele heterozygosity. Our findings revealed that the rate of AA, CC homozygotes, and AC heterozygotes did not differ between groups. Moreover, there was no difference in the distribution of PAPP-A genotypes among the patients with IUGR, PE, IUGR + PE, or eclampsia. Finally, birth weight, rate of the presence of proteinuria, and total protein excretion on 24-hour urine were similar in the subgroups of AA, AC, and CC genotypes in the study group. Our study demonstrated no association between PAPP-A gene rs7020782 polymorphism and PE/IUGR.

Pregnancy-associated plasma protein A (PAPP-A) and preeclampsia

Pregnancy-associated plasma protein A (PAPP-A) is a key regulator of insulin-like growth factor bioavailability essential for normal fetal development. In maternal blood, this protein increases with gestational age and then rapidly decreases after delivery. It is routinely used for Down syndrome screening in the first trimester of pregnancy, and its decrease compared to a normal pregnancy indicates an increased risk for both chromosomal anomalies and adverse pregnancy outcomes. It belongs to a group of biomarkers that predict later preeclampsia development, primarily early onset preeclampsia; however, it should be combined with a Doppler ultrasonography of the uterine artery (pulsatile index) and other biochemical and maternal factors to achieve a higher detection rate with an acceptable false positivity rate. Some studies have demonstrated an even more pronounced decrease of PAPP-A in the early second trimester of pregnancy in women who subsequently develop preeclampsia compared with women who do not develop preeclampsia. Conversely, during the last trimester of pregnancy, its concentration increases even more in patients with preeclampsia than in patients without. It is also detectable at very low levels in nonpregnant individuals, and a higher concentration indicates an adverse effect in patients with acute coronary syndromes or stable atherosclerotic disease and in patients with end-stage renal disease who are being treated with hemodialysis.

Cys327Cys polymorphism of the PAPP-A gene (pregnancy associated plasma protein A) is related to mortality of long term hemodialysis patients

OBJECTIVES

PAPP-A is an independent mortality predictor of long term hemodialysis patients and a prognostic marker of acute coronary syndrome in general population. Cys327Cys PAPP-A polymorphism (SNP) (rs12375498) was found to be of significance in preeclampsia and the C allele of the PAPP-A C/G SNP (rs13290387) was defined as an independent risk factor for acute myocardial infarction. The aim of the study was to test the role of these PAPP-A SNPs in long term hemodialysis patients.

DESIGN AND METHODS

The studied group consisted of 464 subjects - 319 long term hemodialysis patients (183 men, 136 women, 62±14years) and 145 controls (65 men, 80 women, 49±14years). A subgroup of 211 hemodialysis patients (118 men, 93 women, 63±13years) was prospectively followed up for 4.5years. During the follow up, 111 patients died, 51 of them due to cardiovascular events. PAPP-A SNPs were analyzed by DNA sequencing and serum PAPP-A was measured by TRACE.

RESULTS

Both SNPs were in Hardy-Weinberg equilibrium. Allelic and genotype frequencies did not differ between patients and controls and were not related to serum PAPP-A concentrations. Cys327Cys SNP was significant for patients' survival (HR (95% CI): 1.616 (1.110-2.353), nominal p=0.012, corrected p=0.036) while C/G SNP was not.

CONCLUSIONS

Our study shows for the first time the significance of Cys327Cys PAPP-A SNP (rs12375498) for overall mortality of long term hemodialysis patients. Although it does not influence the concentration of PAPP-A it still could affect the correct function of this enzyme which has to be clarified in further studies.