The Norwegian preeclampsia family cohort study: a new resource for investigating genetic aspects and heritability of preeclampsia and related phenotypes.

BACKGROUND: Preeclampsia is a major pregnancy complication without curative treatment available. A Norwegian Preeclampsia Family Cohort was established to provide a new resource for genetic and molecular studies aiming to improve the understanding of the complex pathophysiology of preeclampsia. METHODS: Participants were recruited from five Norwegian hospitals after diagnoses of preeclampsia registered in the Medical birth registry of Norway were verified according to the study's inclusion criteria. Detailed obstetric information and information on personal and family disease history focusing on cardiovascular health was collected. At attendance anthropometric measurements were registered and blood samples were drawn. The software package SPSS 19.0 for Windows was used to compute descriptive statistics such as mean and SD. P-values were computed based on t-test statistics for normally distributed variables. Nonparametrical methods (chi square) were used for categorical variables. RESULTS: A cohort consisting of 496 participants (355 females and 141 males) representing 137 families with increased occurrence of preeclampsia has been established, and blood samples are available for 477 participants. Descriptive analyses showed that about 60% of the index women's pregnancies with birth data registered were preeclamptic according to modern diagnosis criteria. We also found that about 41% of the index women experienced more than one preeclamptic pregnancy. In addition, the descriptive analyses confirmed that preeclamptic pregnancies are more often accompanied with delivery complications. CONCLUSION: The data and biological samples collected in this Norwegian Preeclampsia Family Cohort will provide an important basis for future research. Identification of preeclampsia susceptibility genes and new biomarkers may contribute to more efficient strategies to identify mothers "at risk" and contribute to development of novel preventative therapies.

Metabolomic biomarkers in serum and urine in women with preeclampsia.

OBJECTIVE: To explore the potential of magnetic resonance (MR) metabolomics for study of preeclampsia, for improved phenotyping and elucidating potential clues to etiology and pathogenesis. METHODS: Urine and serum samples from pregnant women with preeclampsia (n = 10), normal pregnancies (n = 10) and non-pregnant women (n = 10) matched by age and gestational age were analyzed with MR spectroscopy and subjected to multivariate analysis. Metabolites were then quantified and compared between groups. RESULTS: Urine and serum samples revealed clear differences between women with preeclampsia and both control groups (normal pregnant and non-pregnant women). Nine urine metabolites were significantly different between preeclampsia and the normal pregnant group. Urine samples from women with early onset preeclampsia clustered together in the multivariate analysis. The preeclampsia serum spectra showed higher levels of low and very-low density lipoproteins and lower levels of high-density lipoproteins when compared to both non-pregnant and normal pregnant women. CONCLUSION: The MR determined metabolic profiles in urine and serum from women with preeclampsia are clearly different from normal pregnant women. The observed differences represent a potential to examine mechanisms underlying different preeclampsia phenotypes in urine and serum samples in larger studies. In addition, similarities between preeclampsia and cardiovascular disease in metabolomics are demonstrated.

PP002. Metabolomic biomarkers in serum and urine of preeclamptic women.

INTRODUCTION: Preeclampsia (PE) affects about 3% of pregnancies. The syndrome cannot be accurately predicted, and large variation complicates the search for early biomarkers. Metabolites are components of the metabolism; the chemical interactions in the body necessary for life. Metabolomics, the study of metabolism, has been used to characterize diabetes, cancer and cardiovascular disease (CVD). OBJECTIVES: Explore the use of magnetic resonance (MR) metabolomics on PE, and to elucidate potential clues to PE etiology and pathogenesis. METHODS: Serum and urine from non-pregnant women (n=10) and pregnant women with PE (n=10) or normal pregnancies (n=10), was analyzed with MR spectroscopy and subjected to multivariate analysis (MVA). Metabolites were quantified and compared between groups. RESULTS: Urine and serum samples revealed differences between PE and both control groups. Ten urine metabolites were significantly different between the three groups. Urine samples from women with early-onset PE clustered together in MVA. PE serum spectra had higher levels of low and very-low density lipoproteins, and lower high-density lipoproteins compared to control groups. CONCLUSION: PE and control samples were effectively discriminated using MR metabolomics, suggesting that MR metabolomics is a useful method for improved sub-phenotyping of PE in larger studies. Information relevant to the disease was found both for serum and urine samples, and indicated similarities between PE and CVD.

PP040. Activation of endosomal toll-like receptors in first trimester trophoblasts.

INTRODUCTION: A mild systemic inflammation may be beneficial to normal pregnancy, however exaggerated inflammation may contribute to pregnancy complications. Infections and cell stress or damage may evoke placental inflammation by activation of Toll-like receptors (TLRs). TLR3, TLR7, TLR8 and TLR9 are located intracellulary on endosomes and are activated by nucleic acids from microbes and damaged cells. Trophoblasts play a crucial role during placentation, and the role of TLRs in first trimester trophoblasts needs to be determined. OBJECTIVES: To characterize endosomal TLR gene expression and activation in first trimester trophoblasts, to extend knowledge of endosomal TLR involvement in placental inflammation. METHODS: Primary trophoblasts were isolated from six first trimester placentas by enzyme degradation and gradient centrifugation. Gene expression of TLR3, TLR7, TLR8 and TLR9 in primary first trimester trophoblasts and the trophoblast cell line BeWo was quantified by RT-qPCR. The trophoblasts were stimulated with ligands for endosomal TLRs, and release of pro-inflammatory cytokines was analyzed by multiplex. RESULTS: Primary first trimester trophoblasts showed gene expression of all endosomal TLRs, and endosomal TLR activation gave increased production of the pro-inflammatory cytokines IL-6, IL-8, and IP-10. CONCLUSION: Primary first trimester trophoblasts express functional endosomal TLRs, indicating TLR-mediated trophoblast involvement in early placental inflammation.

PP042. Cell surface toll-like receptors in primary first trimester trophoblasts.

INTRODUCTION: The first trimester of pregnancy is characterised by a mild pro-inflammatory environment, however excessive inflammation threatens placental development and function. Toll-like receptors (TLRs) are crucial in initiating inflammation. TLR1, TLR2, TLR4, TLR5, TLR6 and TLR10 are expressed on the cell surface, and respond to microbial infection and cell damage and stress signals. Recent findings of TLRs in trophoblasts indicate a role in inflammation during pregnancy, but further studies are warranted. OBJECTIVES: To investigate gene expression and function of cell surface TLRs in first trimester trophoblasts, to extend knowledge on the role of trophoblast TLRs during placental development. METHODS: Primary trophoblasts were isolated from first trimester placentas (n=6) by enzyme degradation and density gradient centrifugation. Gene expression of TLR1, TLR2, TLR4, TLR5, TLR6 and TLR10 was quantified by RT-qPCR in primary first trimester trophoblasts and the trophoblast cell line BeWo. Trophoblasts were stimulated with cell surface TLR ligands and pro-inflammatory cytokine release was analysed by multiplex immunoassay. RESULTS: Primary first trimester trophoblasts expressed all cell surface TLR mRNAs, and activation of TLR2/1, TLR4 and TLR5 induced IL-6 and/or IL-8. CONCLUSION: The broad expression of functional cell surface TLRs in primary first trimester trophoblasts suggests a central role for trophoblasts in placental inflammation and immune activation.