795: Seven eclampsia candidate genes differentially methylated in preeclampsia

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Academic Issues, Antepartum Fetal Assessment, Genetics, Hypertension, Medical-Surgical Complications, Ultrasound-Imaging

794 A longitudinal study of plasma beta-carotene level during pregnancy in relation to the risk of preeclampsia

793 Characterization of discriminatory urinary proteomic biomarkers for severe preeclampsia using seldi-TOF mass spectrometry 1

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Poster Session V

Shu Qin Wei1, Pierre Julien2, Franois Audibert1, Amelie Gagne2, Anne-Monique Nuyt1, Hairong Xu1, Yuquan Wu1, Zhong-Cheng Luo1, William Fraser1

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Seung Mi Lee , Joong Shin Park , Errol Norwitz , Sun Min Kim1, Byoung Jae Kim1, Chan-Wook Park1, Jong Kwan Jun1, Hee Chul Syn1

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University of Montreal, Montreal, QC, 2Laval University, Laval, QC

OBJECTIVE: A longitudinal study of plasma beta-carotene level during

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Seoul National University College of Medicine, Seoul, Tufts University School of Medicine, Boston, MA

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OBJECTIVE: To identify and characterize novel urinary biomarkers that are differentially expressed in women with severe preeclampsia using surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS). STUDY DESIGN: Urine samples were collected from women with severe preeclampsia (n⫽11 [sPE]), mild preeclampsia (n⫽7 [mPE]), and normotensive controls (n⫽8) and analyzed individually using SELDI-TOF-MS to identify discriminatory protein peaks in the sPE cohort. A scoring system was constructed— designated Preeclampsia Proteomic Score of Urine (PPSU)—to differentiate sPE from mPE and normotensive controls: the presence of a discriminatory peak was assigned a score of 1, the absence of the peak was scored as 0, and the total number of discriminatory protein peaks present in each urine sample was converted to a numeric score, which was defined as PPSU. RESULTS: Four discriminatory protein peaks were identified (m/z ratio: 4155, 6044, 6663, and 7971), all of which were down-regulated in women with sPE. PPSU scores in women with sPE were significantly lower than that in both mPE and controls (sPE 0 [0-4] vs mPE 3 [0-4] vs controls 4 [2-4]; median [range]; P⬍0.05 for both). PPSU⬍2 had a sensitivity of 90.9% and specificity of 93.3% in discriminating patients with sPE from mPE and controls (Figure). CONCLUSIONS: Proteomic analysis of urine can accurately distinguish sPE from mPE and normotensive controls. Additional studies are underway to identify and characterize these proteomic biomarkers, and to determine the role of these differentially expressed proteins in the pathogenesis of preeclampsia. (Legend of the figure: ROC curve showing performance of PPSU score in discriminating patients with sPE from mPE and controls)

pregnancy in relation to the risk of preeclampsia. STUDY DESIGN: A nested case-control study using a prospective pregnancy cohort from a trial of antioxidant supplementation for the prevention of PE (INTAPP). Plasma beta-carotene levels were measured longitudinally at 12-18 weeks (prior to intervention), 24-26 weeks, and 32-34 weeks of gestation using high-performance liquid chromatography (HPLC) with coulometric electrochemical detection. A total of 115 women with PE and 229 matched controls were included. We used logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (95% CI). RESULTS: Longitudal analyses of maternal plasma beta-carotene concentrations demonstrate no change across gestation (12-14 weeks vs. 24-26 weeks vs. 32-34 weeks) (p⬎ 0.05). The plasma beta-carotene concentrations were significant lower in the patients with PE compared to the normontensive controls at the above different gestational ages (␮g/ml) (mean⫾SD:0.65⫾0.60 vs. 0.83⫾0.52; 0.62⫾0.62 vs. 0.89⫾0.60; 0.69⫾0.62 vs. 0.90⫾0.69; respectively, p⬍0.05). After multivariate adjustment, women with beta-carotene concentrations in the lowest quartiles, experienced a 3-6 fold increased risk of preeclampsia (using the highest quartile as referent group; 12-14 weeks: OR 3.62, 95%CI 1.88 ⫺6.97; 24-26 weeks: OR 6.03, 95% CI 3.07 ⫺11.85; at 32-34 weeks: OR 2.88, 95%CI 1.42- 5.83). CONCLUSIONS: Although plasma beta-carotene concentration remained unchanged across gestation, lower beta-carotene levels were associated with an increased risk of PE.

795 Seven eclampsia candidate genes differentially methylated in preeclampsia Wendy White1, Brian Brost1, Joshua Nitsche1, Jonathan O’Brien1, William Watson1, Carl Rose1, Norman Davies1, Kent Bailey1, Stephen Turner1, Vesna Garovic1 1

Mayo Clinic College of Medicine, Rochester, MN

OBJECTIVE: Altered gene expression in biomarkers associated with

preeclampsia/eclampsia (PE) could be explained in part by epigenetic phenomena such as variable methylation. STUDY DESIGN: Genome wide methylation profiles of maternal DNA were evaluated in 14 PE cases and 14 normotensive controls. Subjects were nulliparous, non-smokers, age and BMI matched. Genomic DNA was run on the Illumina Methylation Assay 27,578 CpG sites genome wide. Mean methylation at sites in genes from a Metacoredefined eclampsia gene set present on our platform were compared using a t-test. RESULTS: QC confirmed high correlation of replicates and detection p values ⬎95%. Of the 39 genes in the “eclampsia gene set”, 34 were present on our platform with 73 CpG sites. Seven out of 34 tested in this gene set had differential methylation with p value ⬍0.05. Two genes were found to be less methylated in PE which may result in more expression. AGT (-3%; p⫽ 0.027), angiotensin, is a potent vasoconstrictor with exaggerated effect in PE. DDAH1 (-6%; p⫽0.031) is involved in nitric oxide generation, via asymmetric dimethylarginine (ADMA), levels of which are known to be altered in PE. Five genes were more methylated and therefore may correlate with reduced transcription. CALCA (⫹4%; p⫽0.001) forms calcitonin-gene related peptide, a potent vasodilator decreased in the PE. F5 (⫹1%; p⫽0.016), coagulation Factor V, is a target of activated protein C, and increased resistance related to genetic variants (Factor V Leiden) or pregnancy have been associated with PE. MTHFR (⫹3%; p⫽0.041) regulates homocysteine; high levels are associated with a 20x increase in risk for PE. POMC (⫹4%; p⫽0.014) produces beta endorphin and Supplement to JANUARY 2011 American Journal of Obstetrics & Gynecology

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Academic Issues, Antepartum Fetal Assessment, Genetics, Hypertension, Medical-Surgical Complications, Ultrasound-Imaging

through ACTH stimulates aldosterone, both decreased in PE. PTGS2 (⫹3%; p⫽0.03) is part of the COX 2 prostaglandin pathway involved in inflammation. CONCLUSIONS: This is the first study that we know of that describes methylation differences in eclampsia candidate genes from maternal DNA. The differential methylation of these 7 genes may affect transcription and explain known alterations in gene product associated with PE.

796 History of hypertension in pregnancy predicts hyperhomocysteinemia decades later Wendy White1, Brian Brost1, Vesna Garovic1, Joshua Nitsche1, Jonathan O’Brien1, William Watson1, Carl Rose1, Norman Davies1, Kent Bailey1, Heather Wiste1, Stephen Turner1 1

Mayo Clinic College of Medicine, Rochester, MN

OBJECTIVE: Hypertension in pregnancy is increasingly recognized as a

predictor of future cardiovascular disease. Elevated plasma homocysteine has been noted in preeclampsia and is also a recognized biomarker for cardiovascular morbidity later in life. We sought to determine if a history of hypertension in pregnancy was an independent risk factor for hyperhomocysteinemia later in life. STUDY DESIGN: This was a cohort of 2429 women in the GENOA network of the Family Blood Pressure Program, who were assessed at a median age of 61 years old. A validated questionnaire was used to determine history of nulliparity, normotensive, or hypertensive pregnancy. Other covariates including family history, age at assessment, education level, race, BMI, diabetes, tobacco, hypertension, and use of statins were determined by structured interview and physical examination. Serum homocysteine was measured by the Mayo Clinic HPLC method and elevated homocysteine was defined as ⬎13 micromol/L. Multiple linear and logistic regression models were used to assess relationships between history of hypertension during pregnancy and homocysteine levels measured at the time of assessment. RESULTS: A history of hypertension in pregnancy, when compared with normotensive pregnancy, predicted a 4.5% higher serum homocysteine level (p⫽0.011) and a 1.64-fold increased odds of having elevated homocysteine (95% CI, 1.18-2.28, p⫽0.003) after adjustment for potentially confounding covariates. In contrast, a history of normotensive pregnancy, as compared with nulliparity, predicted a 0.49-fold reduced odds of elevated homocysteine (95% CI, 0.320.74,p ⬍0.001). CONCLUSIONS: A history of hypertension in pregnancy predicts higher homocysteine levels decades later in life and may be a mediator in the pathway that links a history of hypertension in pregnancy with future cardiovascular risk. Normotensive pregnancy, in contrast, indicates a ”negative stress test” associated with lower biomarkers of CVD risk later in life. Pregnancy history should become part of CVD risk assessment and factor into decisions about screening and primary prevention.

797 Genome wide methylation profiling in preeclamptic pregnancies yields novel neuronal candidate genes that may explain seizure susceptibility or the protective effect of magnesium Wendy White1, Brian Brost1, Joshua Nitsche1, Jonathan O’Brien1, William Watson1, Carl Rose1, Norman Davies1, Kent Bailey1, Stephen Turner1, Vesna Garovic1 1

Mayo Clinic College of Medicine, Rochester, MN

OBJECTIVE: Preeclampsia (PE) is a major source of maternal and fetal

morbidity and mortality worldwide. Seizures complicate up to 3% of cases of preeclampsia. It is not well understood why this occurs or who is most at risk. This study sought to determine if a genome wide assessment of DNA methylation in PE could identify novel biomarkers associated with the disease state. STUDY DESIGN: Genome wide methylation profiles of maternal DNA from blood were obtained at the time of delivery in 14 PE cases and 14

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normotensive controls. The patients were nulliparous, non-smokers and were matched for age and BMI. Genomic DNA was derived from buffy coat, purified, and bisulfite modified then run on the Illumina Methylation Assay platform looking at 27,578 CpG sites in 14,495 genes. Mean methylation levels at each CpG site were compared using a t-test. RESULTS: Magnesium prophylaxis was used in 9 of 14 PE cases due to a severe phenotype; none of the controls were exposed to magnesium. There did not appear to be an association between methylation and magnesium exposure. When ranked by p value, 4 of the top 15 genes found to be differentially methylated in PE compared with controls were surprisingly highly expressed in the brain. GRIN2b, 6% more methylated in PE (p⫽0.00006), produces a NMDA excitatory neurotransmitter receptor which has voltage dependent sensitivity to magnesium. PCDHB7, 6% more methylated in PE (p ⫽ 0.00007), is involved in the establishment and function of specific cell-cell neural connections. BEX1, 3% more methylated in PE (p⫽0.0003), plays a role in cell cycle progression and neuronal differentiation. GABRA1, 5% more methylated in PE (p⫽0.00066), produces a major inhibitory neurotransmitter and is associated with epilepsy. CONCLUSIONS: Genome wide methylation profiling of preeclamptic cases suggests novel eclampsia candidate genes that are highly expressed in the brain. Further investigation of these genes in terms of SNP frequencies, gene expression and protein levels may lead to a better understanding of both the physiology of seizure activity in PE and the mechanism of action of magnesium prophylaxis.

798 Improving patient understanding of preeclamspsia: a randomized controlled trial Whitney You1, Michael Wolf2, Stacy Bailey2, William A. Grobman3 1

Naval Medical Center San Diego, San Diego, CA, 2Institute for Healthcare Studies, Northwestern University, Chicago, IL, 3Northwestern University, Feinberg School of Medicine, Chicago, IL

OBJECTIVE: Ninety million people have low health literacy, however, there is a paucity of information regarding how to enhance patient understanding in obstetrics. Recently, our group has shown that many women have a poor understanding of preeclampsia. We developed an educational tool to inform women about the syndrome, the symptoms associated with it, and what to do should they experience these symptoms. The objective of this study was to assess whether this tool could improve understanding of preeclampsia. STUDY DESIGN: This was a randomized controlled trial that took place in a tertiary care, urban, university hospital. One hundred and twenty women were randomly assigned to: 1) the preeclampsia educational tool 2) a standard ACOG pamphlet or 3) no additional information. The preeclampsia educational tool was a graphics-based card with minimum text created with the input of obstetricians, health literacy researchers, and patient focus groups. Preeclampsia knowledge was assessed using a questionnaire that addressed the symptoms, consequences, and proper patient actions associated with preeclampsia. Additional information about demographics, medical history, and health literacy was obtained. Health literacy was assessed using the Newest Vital Sign. RESULTS: The mean age of the participants was 27.2 (⫾ 5.9) years, 62% were multiparous, approximately half were African American, and 52% were deemed to have adequate literacy. There were no differences between the groups according to demographic characteristics. Patients who received the educational tool scored significantly better on a test of preeclampsia knowledge than those who received the ACOG pamphlet or no additional information (71%, 63%, 49%, respectively, p ⬍ 0.05). This improved understanding was equally evident among women with adequate and inadequate health literacy (interaction ⬎ .05). CONCLUSIONS: A graphics-based preeclampsia educational tool has the ability to significantly improve patient understanding of pre-

American Journal of Obstetrics & Gynecology Supplement to JANUARY 2011