A Non-Targeted LC-MS Profiling Reveals Elevated Levels of Carnitine Precursors and Trimethylated Compounds in the Cord Plasma of Pre-Eclamptic Infants

Preeclampsia (PE) is a complex pregnancy disorder. It is not extensively known how the metabolic alterations of PE women contribute to the metabolism of newborn. We applied liquid chromatography-mass spectrometry (LC-MS) based non-targeted meta bolomics to determine whether the metabolic profile of plasma from umbilical cord differs between infants born to PE and non-PE pregnancies in the FINNPEC study. Cord plasma was available from 42 newborns born from PE and 53 from non-PE pregnancies. 133 molecular features differed between PE and non-PE newborns after correction for multiple testing. Decreased levels of 4-pyridoxic acid were observed in the cord plasma samples of PE newborns when compared to non-PE newborns. Compounds representing following areas of metabolism were increased in the cord plasma of PE newborns: urea and creatine metabolism; carnitine biosynthesis and acylcarnitines; putrescine metabolites; tryptophan metabolism and phosphatidylcholines. To our knowledge, this study is the first one to apply LC-MS based meta bolomics in cord plasma of PE newborns. We demonstrate that this strategy provides a global picture of the widespread metabolic alterations associated with PE and particularly the elevated levels of carnitine precursors and trimethylated compounds appear to be associated with PE at birth.Peer reviewe

Cohort profile: the Finnish Genetics of Pre-eclampsia Consortium (FINNPEC)

Peer reviewe

Searching for a paternal phenotype for preeclampsia

Introduction Preeclampsia (PE) is a heterogeneous disorder and research to date has principally focused on maternal factors. In this study, however, we considered the associations between background factors and preeclampsia in men who fathered preeclamptic and non-preeclamptic pregnancies. Material and methods From 2008 to 2011, participants in the Finnish Genetics of Pre-eclampsia Consortium (FINNPEC) cohort completed a questionnaire on their background information. Questionnaire data were available from 586 men who had fathered a preeclamptic pregnancy (PE fathers) and 660 control men who had fathered a non-preeclamptic pregnancy. Two different control groups were established: Group 1: healthy controls (n = 457), which consisted of fathers whose current partners were healthy women with uncomplicated pregnancies; Group 2: other controls (n = 203), which also included fathers whose current partners had other pregnancy complications. Results The PE fathers more often reported preeclampsia in a previously fathered pregnancy (p < 0.05 for all). The PE and control fathers were similar in age, body mass index, smoking, and preexisting medical conditions. There were no differences in the socioeconomic background or health history of the PE and control fathers or their parents. Conclusions In the FINNPEC study cohort, the occurrence of preeclampsia in a previously fathered pregnancy was more common among the men who had fathered a preeclamptic pregnancy; other paternal phenotypic and lifestyle characteristics did not play a significant role in preeclampsia susceptibility of their partners.Peer reviewe

Genetic predisposition to hypertension is associated with preeclampsia in European and Central Asian women

Research leading to these results was conducted as part of the InterPregGen study, which received funding from the European Union Seventh Framework Programme under grant agreement no. 282540 and was supported by Wellcome Trust grant 098051. Some data used for the research were obtained from THL Biobank. We thank all study participants for their generous participation at THL Biobank. Part of this work was conducted using the UK Biobank Resource under application number 24711. A full list of acknowledgments appears in Supplementary Note 3. Publisher Copyright: © 2020, The Author(s).Preeclampsia is a serious complication of pregnancy, affecting both maternal and fetal health. In genome-wide association meta-analysis of European and Central Asian mothers, we identify sequence variants that associate with preeclampsia in the maternal genome at ZNF831/20q13 and FTO/16q12. These are previously established variants for blood pressure (BP) and the FTO variant has also been associated with body mass index (BMI). Further analysis of BP variants establishes that variants at MECOM/3q26, FGF5/4q21 and SH2B3/12q24 also associate with preeclampsia through the maternal genome. We further show that a polygenic risk score for hypertension associates with preeclampsia. However, comparison with gestational hypertension indicates that additional factors modify the risk of preeclampsia.Peer reviewe

Genetic Analysis of Membrane Cofactor Protein (CD46) of the Complement System in Women with and without Preeclamptic Pregnancies

E. Kajantie ja J. Kere työryhmän FINNPEC Core Investigator Group jäseniä.Peer reviewe

Gene expression profiling of pre-eclamptic placentae by RNA sequencing

Pre-eclampsia is a common and complex pregnancy disorder that often involves impaired placental development. In order to identify altered gene expression in pre-eclamptic placenta, we sequenced placental transcriptomes of nine pre-eclamptic and nine healthy pregnant women in pools of three. The differential gene expression was tested both by including all the pools in the analysis and by excluding some of the pools based on phenotypic characteristics. From these analyses, we identified altogether 53 differently expressed genes, a subset of which was validated by qPCR in 20 cases and 19 controls. Furthermore, we conducted pathway and functional analyses which revealed disturbed vascular function and immunological balance in pre-eclamptic placenta. Some of the genes identified in our study have been reported by numerous microarray studies (BHLHE40, FSTL3, HK2, HTRA4, LEP, PVRL4, SASH1, SIGLEC6), but many have been implicated in only few studies or have not previously been linked to pre-eclampsia (ARMS2, BTNL9, CCSAP, DIO2, FER1L4, HPSE, LOC100129345, LYN, MYO7B, NCMAP, NDRG1, NRIP1, PLIN2, SBSPON, SERPINB9, SH3BP5, TET3, TPBG, ZNF175). Several of the molecules produced by these genes may have a role in the pathogenesis of pre-eclampsia, and some could qualify as biomarkers for prediction or detection of this pregnancy complication.Peer reviewe

A non-targeted LC-MS metabolic profiling of pregnancy : longitudinal evidence from healthy and pre-eclamptic pregnancies

IntroductionMaternal metabolism changes substantially during pregnancy. However, few studies have used metabolomics technologies to characterize changes across gestation.Objectives and methodsWe applied liquid chromatography-mass spectrometry (LC-MS) based non-targeted metabolomics to determine whether the metabolic profile of serum differs throughout the pregnancy between pre-eclamptic and healthy women in the FINNPEC (Finnish Genetics of Preeclampsia Consortium) Study. Serum samples were available from early and late pregnancy.ResultsProgression of pregnancy had large-scale effects to the serum metabolite profile. Altogether 50 identified metabolites increased and 49 metabolites decreased when samples of early pregnancy were compared to samples of late pregnancy. The metabolic signatures of pregnancy were largely shared in pre-eclamptic and healthy women, only urea, monoacylglyceride 18:1 and glycerophosphocholine were identified to be increased in the pre-eclamptic women when compared to healthy controls.ConclusionsOur study highlights the need of large-scale longitudinal metabolomic studies in non-complicated pregnancies before more detailed understanding of metabolism in adverse outcomes could be provided. Our findings are one of the first steps for a broader metabolic understanding of the physiological changes caused by pregnancy per se.Peer reviewe

Dysfunction of complement receptors CR3 (CD11b/18) and CR4 (CD11c/18) in pre-eclampsia : a genetic and functional study

Objective To study genetic variants and their function within genes coding for complement receptors in pre-eclampsia. Design A case-control study. Setting Pre-eclampsia is a common vascular disease of pregnancy. The clearance of placenta-derived material is one of the functions of the complement system in pregnancy. Population We genotyped 500 women with pre-eclamptic pregnancies and 190 pregnant women without pre-eclampsia, as controls, from the FINNPEC cohort, and 122 women with pre-eclamptic pregnancies and 1905 controls from the national FINRISK cohort. Methods The functional consequences of genotypes discovered by targeted exomic sequencing were explored by analysing the binding of the main ligand iC3b to mutated CR3 or CR4, which were transiently expressed on the surface of COS-1 cells. Main outcome measures Allele frequencies were compared between pre-eclamptic pregnancies and controls in genetic studies. The functional consequences of selected variants were measured by binding assays. Results The most significantly pre-eclampsia-linked CR3 variant M441K (P = 4.27E-4, OR = 1.401, 95% CI = 1.167-1.682) displayed a trend of increased adhesion to iC3b (P = 0.051). The CR4 variant A251T was found to enhance the adhesion of CR4 to iC3b, whereas W48R resulted in a decrease of the binding of CR4 to iC3b. Conclusions Results suggest that changes in complement-facilitated phagocytosis are associated with pre-eclampsia. Further studies are needed to ascertain whether aberrant CR3 and CR4 activity leads to altered pro- and anti-inflammatory cytokine responses in individuals carrying the associated variants, and the role of these receptors in pre-eclampsia pathogenesis. Tweetable abstract Genetic variants of complement receptors CR3 and CR4 have functional consequences that are associated with pre-eclampsia.Peer reviewe

A non-targeted LC-MS metabolic profiling of pregnancy: longitudinal evidence from healthy and pre-eclamptic pregnancies

IntroductionMaternal metabolism changes substantially during pregnancy. However, few studies have used metabolomics technologies to characterize changes across gestation.Objectives and methodsWe applied liquid chromatography–mass spectrometry (LC–MS) based non-targeted metabolomics to determine whether the metabolic profile of serum differs throughout the pregnancy between pre-eclamptic and healthy women in the FINNPEC (Finnish Genetics of Preeclampsia Consortium) Study. Serum samples were available from early and late pregnancy.ResultsProgression of pregnancy had large-scale effects to the serum metabolite profile. Altogether 50 identified metabolites increased and 49 metabolites decreased when samples of early pregnancy were compared to samples of late pregnancy. The metabolic signatures of pregnancy were largely shared in pre-eclamptic and healthy women, only urea, monoacylglyceride 18:1 and glycerophosphocholine were identified to be increased in the pre-eclamptic women when compared to healthy controls.ConclusionsOur study highlights the need of large-scale longitudinal metabolomic studies in non-complicated pregnancies before more detailed understanding of metabolism in adverse outcomes could be provided. Our findings are one of the first steps for a broader metabolic understanding of the physiological changes caused by pregnancy per se.</p