Metabolomic identification of placental alterations in fetal growth restriction.

INTRODUCTION: Fetal growth restriction (FGR), viz., birth weight <10th percentile is a common pregnancy complication which increases the risk of adverse fetal and newborn outcomes. The placenta is the key organ for fetal growth as it controls oxygen and nutrient availability. This study aims to elucidate the mechanisms of and identify putative placental biomarkers for FGR using high-resolution metabolomics. METHODS: Placenta samples from 19 FGR cases and 30 controls were analyzed using proton magnetic resonance (1H NMR) spectroscopy and direct flow injection mass spectrometry with reverse-phase liquid-chromatography mass spectrometry (DI-LC-MS/MS). Significant concentration differences (p-value <.05) in 179 of the 220 metabolites were measured. RESULTS: Of the 179 metabolites, 176 (98.3%) had reduced placental levels in FGR cases. The best performing metabolite model: 3-hydroxybutyrate, glycine and PCaaC42:0 achieved an AUC (95% CI) = 0.912 (0.814-1.000) with a sensitivity of 86.7% and specificity of 84.2% for FGR detection. Metabolite set enrichment analysis (MSEA) revealed significant (p < .05) perturbation of multiple placental metabolite pathways including urea metabolism, ammonia recycling, porphyrin metabolism, bile acid biosynthesis, galactose metabolism and perturbed protein biosynthesis. CONCLUSION: The placental metabolic pathway analysis revealed abnormalities that are consistent with fetal hepatic dysfunction in FGR. Near global reduction of metabolite concentrations was found in the placenta from FGR cases and metabolites demonstrated excellent diagnostic accuracy for FGR detection.

First-trimester metabolomic prediction of stillbirth.

Background: Stillbirth remains a major problem in both developing and developed countries. Omics evaluation of stillbirth has been highlighted as a top research priority. Objective: To identify new putative first-trimester biomarkers in maternal serum for stillbirth prediction using metabolomics-based approach. Methods: Targeted, nuclear magnetic resonance (NMR) and mass spectrometry (MS), and untargeted liquid chromatography-MS (LC-MS) metabolomic analyses were performed on first-trimester maternal serum obtained from 60 cases that subsequently had a stillbirth and 120 matched controls. Metabolites by themselves or in combination with clinical factors were used to develop logistic regression models for stillbirth prediction. Prediction of stillbirths overall, early (<28 weeks and <32 weeks), those related to growth restriction/placental disorder, and unexplained stillbirths were evaluated. Results: Targeted metabolites including glycine, acetic acid, L-carnitine, creatine, lysoPCaC18:1, PCaeC34:3, and PCaeC44:4 predicted stillbirth overall with an area under the curve [AUC, 95% confidence interval (CI)] = 0.707 (0.628-0.785). When combined with clinical predictors the AUC value increased to 0.740 (0.667-0.812). First-trimester targeted metabolites also significantly predicted early, unexplained, and placental-related stillbirths. Untargeted LC-MS features combined with other clinical predictors achieved an AUC (95%CI) = 0.860 (0.793-0.927) for the prediction of stillbirths overall. We found novel preliminary evidence that, verruculotoxin, a toxin produced by common household molds, might be linked to stillbirth. Conclusions: We have identified novel biomarkers for stillbirth using metabolomics and demonstrated the feasibility of first-trimester prediction.

Genome-Wide DNA Methylation Analysis and Epigenetic Variations Associated with Congenital Aortic Valve Stenosis (AVS).

Congenital heart defect (CHD) is the most common cause of death from congenital anomaly. Among several candidate epigenetic mechanisms, DNA methylation may play an important role in the etiology of CHDs. We conducted a genome-wide DNA methylation analysis using an Illumina Infinium 450k human methylation assay in a cohort of 24 newborns who had aortic valve stenosis (AVS), with gestational-age matched controls. The study identified significantly-altered CpG methylation at 59 sites in 52 genes in AVS subjects as compared to controls (either hypermethylated or demethylated). Gene Ontology analysis identified biological processes and functions for these genes including positive regulation of receptor-mediated endocytosis. Consistent with prior clinical data, the molecular function categories as determined using DAVID identified low-density lipoprotein receptor binding, lipoprotein receptor binding and identical protein binding to be over-represented in the AVS group. A significant epigenetic change in the APOA5 and PCSK9 genes known to be involved in AVS was also observed. A large number CpG methylation sites individually demonstrated good to excellent diagnostic accuracy for the prediction of AVS status, thus raising possibility of molecular screening markers for this disorder. Using epigenetic analysis we were able to identify genes significantly involved in the pathogenesis of AVS.

Metabolomics of biomarker discovery in ovarian cancer: a systematic review of the current literature.

INTRODUCTION: Metabolomics is the emerging member of "omics" sciences advancing the understanding, diagnosis and treatment of many cancers, including ovarian cancer (OC). OBJECTIVES: To systematically identify the metabolomic abnormalities in OC detection, and the dominant metabolic pathways associated with the observed alterations. METHODS: An electronic literature search was performed, up to and including January 15th 2016, for studies evaluating the metabolomic profile of patients with OC compared to controls. QUADOMICS tool was used to assess the quality of the twenty-three studies included in this systematic review. RESULTS: Biological samples utilized for metabolomic analysis include: serum/plasma (n = 13), urine (n = 4), cyst fluid (n = 3), tissue (n = 2) and ascitic fluid (n = 1). Metabolites related to cellular respiration, carbohydrate, lipid, protein and nucleotide metabolism were significantly altered in OC. Increased levels of tricarboxylic acid cycle intermediates and altered metabolites of the glycolytic pathway pointed to perturbations in cellular respiration. Alterations in lipid metabolism included enhanced fatty acid oxidation, abnormal levels of glycerolipids, sphingolipids and free fatty acids with common elevations of palmitate, oleate, and myristate. Increased levels of glutamine, glycine, cysteine and threonine were commonly reported while enhanced degradations of tryptophan, histidine and phenylalanine were found. N-acetylaspartate, a brain amino acid, was found elevated in primary and metastatic OC tissue and ovarian cyst fluid. Further, elevated levels of ketone bodies including 3-hydroxybutyrate were commonly reported. Increased levels of nucleotide metabolites and tocopherols were consistent through out the studies. CONCLUSION: Metabolomics presents significant new opportunities for diagnostic biomarker development, elucidating previously unknown mechanisms of OC pathogenesis.

Risk factors for sclerema neonatorum in preterm neonates in Bangladesh.

BACKGROUND: This study presents a retrospective analysis of risk factors for sclerema neonatorum in preterm neonates in Bangladesh. METHODS: Preterm neonates admitted to Dhaka Shishu Hospital in Bangladesh were enrolled in a clinical trial to evaluate the effects of topical treatment with skin barrier-enhancing emollients on prevention of sepsis and mortality. Four hundred ninety-seven neonates were enrolled in the study and 51 (10.3%) developed sclerema neonatorum. We explored risk factors for sclerema neonatorum by comparing patients with and without sclerema neonatorum. Diagnosis of sclerema neonatorum was based on the presence of uniform hardening of skin and subcutaneous tissues to the extent that the skin could not be pitted nor picked up and pinched into a fold. Cultures of blood and cerebrospinal fluid were obtained in all neonates with clinical suspicion of sepsis. RESULTS: In multivariate analysis, lower maternal education (OR: 1.94; 95% CI: 1.02-3.69; P = 0.043), and signs of jaundice (OR: 2.82; 95% CI: 1.19-6.69; P = 0.018) and poor feeding (OR: 4.71; 95% CI: 1.02-21.74; P = 0.047) on admission were risk factors for developing sclerema neonatorum. The incidence rate ratio of sepsis in neonates who developed sclerema neonatorum was 1.81 (95% CI: 1.16-2.73; P = 0.004), primarily due to Gram-negative pathogens, and risk of death in infants with sclerema neonatorum was 46.5-fold higher (P < 0.001, 95% CI: 6.37-339.81) than for those without sclerema neonatorum. CONCLUSIONS: Sclerema neonatorum was a relatively common, grave condition in this setting, heralded by poor feeding, jaundice, and bacteremia, and signaling the need for prompt antibiotic treatment.

Neonatal mortality, risk factors and causes: a prospective population-based cohort study in urban Pakistan.

OBJECTIVE: To evaluate the prevalence, sex distribution and causes of neonatal mortality, as well as its risk factors, in an urban Pakistani population with access to obstetric and neonatal care. METHODS: Study area women were enrolled at 20-26 weeks' gestation in a prospective population-based cohort study that was conducted from 2003 to 2005. Physical examinations, antenatal laboratory tests and anthropometric measures were performed, and gestational age was determined by ultrasound to confirm eligibility. Demographic and health data were also collected on pretested study forms by trained female research staff. The women and neonates were seen again within 48 hours postpartum and at day 28 after the birth. All neonatal deaths were reviewed using the Pattinson et al. system to assign obstetric and final causes of death; the circumstances of the death were determined by asking the mother or family and by reviewing hospital records. Frequencies and rates were calculated, and 95% confidence intervals were determined for mortality rates. Relative risks were calculated to evaluate the associations between potential risk factors and neonatal death. Logistic regression models were used to compute adjusted odds ratios. FINDINGS: Birth outcomes were ascertained for 1280 (94%) of the 1369 women enrolled. The 28-day neonatal mortality rate was 47.3 per 1000 live births. Preterm birth, Caesarean section and intrapartum complications were associated with neonatal death. Some 45% of the deaths occurred within 48 hours and 73% within the first week. The primary obstetric causes of death were preterm labour (34%) and intrapartum asphyxia (21%). Final causes were classified as immaturity-related (26%), birth asphyxia or hypoxia (26%) and infection (23%). Neither delivery in a health facility nor by health professionals was associated with fewer neonatal deaths. The Caesarean section rate was 19%. Almost all (88%) neonates who died received treatment and 75% died in the hospital. CONCLUSION: In an urban population with good access to professional care, we found a high neonatal mortality rate, often due to preventable conditions. These results suggest that, to decrease neonatal mortality, improved health service quality is crucial.

Reasons of refusal and drop out in a follow up study involving primigravidae in Pakistan.

OBJECTIVE: To determine the reasons underlying the refusals to participate and drop outs from a follow up study involving primigravidae. DESIGN: A descriptive study. METHODS: Aga Khan University and Aga Khan Hospital for Women, Karachi, jointly initiated a nested case-control study on primigravidae for determining the predictability of preeclampsia using various biochemical markers in blood. The protocol-eligible study subjects were counseled along with their accompanying family members to participate in the study. All women recruited in this study were followed up throughout their pregnancy till delivery. RESULTS: One thousand six hundred and sixty-five primigravidae were identified as the potential study subjects. Out of which, 1,307 (78.5%) consented and 358 (21.5%) refused to participate in the study. The most common reason underlying the refusal was inability to get permission from the family members (n=84; 34.4%) followed by fear of prick (n=51; 20.9%). For 114 refusals, either the reason was not mentioned by the counseled women (n=60) or the data was missing (n=54). Out of 1,307 women recruited in the research, only 611 (46.7%) women completed the study according to the prescribed protocol. Among the rest, 102 (7.8%) subsequently withdrew from the research, 503 (38.5%) were dropped out, and 91 (7.0%) were lost to follow up. CONCLUSIONS: Refusal to participate and drop out from the research program are two significant factors hindering the smooth flow of a study. In Pakistan, the major reason for the refusal by the protocol-eligible pregnant women for participating in a research program is the unwillingness of the family members.