Unraveling the metabolomic architecture of autism in a large Danish population-based cohort.

BACKGROUND: The prevalence of autism in Denmark has been increasing, reaching 1.65% among 10-year-old children, and similar trends are seen elsewhere. Although there are several factors associated with autism, including genetic, environmental, and prenatal factors, the molecular etiology of autism is largely unknown. Here, we use untargeted metabolomics to characterize the neonatal metabolome from dried blood spots collected shortly after birth. METHODS: We analyze the metabolomic profiles of a subset of a large Danish population-based cohort (iPSYCH2015) consisting of over 1400 newborns, who later are diagnosed with autism and matching controls and in two Swedish population-based cohorts comprising over 7000 adult participants. Mass spectrometry analysis was performed by a timsTOF Pro operated in QTOF mode, using data-dependent acquisition. By applying an untargeted metabolomics approach, we could reproducibly measure over 800 metabolite features. RESULTS: We detected underlying molecular perturbations across several metabolite classes that precede autism. In particular, the cyclic dipeptide cyclo-leucine-proline (FDR-adjusted p = 0.003) and the carnitine-related 5-aminovaleric acid betaine (5-AVAB) (FDR-adjusted p = 0.03), were associated with an increased probability for autism, independently of known prenatal and genetic risk factors. Analysis of genetic and dietary data in adults revealed that 5-AVAB was associated with increased habitual dietary intake of dairy (FDR-adjusted p < 0.05) and with variants near SLC22A4 and SLC22A5 (p < 5.0e - 8), coding for a transmembrane carnitine transporter protein involved in controlling intracellular carnitine levels. CONCLUSIONS: Cyclo-leucine-proline and 5-AVAB are associated with future diagnosis of autism in Danish neonates, both representing novel early biomarkers for autism. 5-AVAB is potentially modifiable and may influence carnitine homeostasis.

Levels of cytokines in the cerebrospinal fluid of patients with psychotic disorders compared to individually matched healthy controls.

BACKGROUND: Increased peripheral cytokine levels have been observed in patients with psychotic disorders; however, large high-quality studies with individually matched healthy controls have been lacking regarding cytokines in cerebrospinal fluid (CSF) of individuals with psychotic disorders. METHODS: Patients diagnosed with a non-organic, non-affective psychotic disorder (ICD-10: F20/22-29) within a year prior to inclusion and individually age- and sex-matched healthy controls were included by identical in- and exclusion criteria's except for the psychiatric diagnoses. All participants were aged 18-50 years and individuals with neurological or immunological disorders were excluded. CSF cytokines were analyzed with MesoScale V-PLEX neuroinflammation panel. Co-primary outcomes were CSF interleukin-6 (IL-6) and IL-8. RESULTS: We included 104 patients and 104 healthy controls, matching on age, sex and BMI. No significant differences were found for the primary outcomes IL-6 (relative mean difference (MD): 0.97, 95 %CI: 0.84-1.11, p = 0.637) or IL-8 (MD: 1.01, 95 %CI: 0.93-1.09, p = 0.895). Secondary analyses found patients to have higher IL-4 (MD: 1.30, 95 %CI: 1.04-1.61, p = 0.018), a trend towards higher IFN-γ (MD: 1.26, 95 %CI: 0.99-1.59, p = 0.056), and lower IL-16 (MD: 0.83, 95 %CI: 0.74-0.94, p = 0.004) than healthy controls, though not significant after correction for multiple testing. IL-8 and IL-16 were found positively associated with CSF white blood cells and CSF/serum albumin ratio. The study was limited by 77.9 % of the patients being on antipsychotic treatment at time of intervention, and that levels of nine of the 26 cytokines were below lower limit of detection (LLOD) in >50 % of samples; however, for the primary outcomes IL-6 and IL-8 more than 99.5 % of the samples were above LLOD and for IL-8 all samples exceeded the lower limit of quantification (LLOQ). CONCLUSIONS: We found no evidence of increased IL-6 and IL-8 in patients with recent-onset psychotic disorders in contrary to previous findings in meta-analyses of CSF cytokines. Secondary analyses found indication of higher IL-4, decreased IL-16, and borderline increased IFN-γ in patients, neither of which have previously been reported on in CSF analyses of individuals with psychotic disorders.

High level of immunoglobulin G targeting mycoplasma or cytomegalovirus in the newborn increases risk of ADHD.

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder typically detected in childhood. Although ADHD has been demonstrated to have a strong genetic component, environmental risk factors, such as maternal infections during pregnancy, may also play a role. We therefore measured the immunological response to 5 abundant microorganisms (Toxoplasmosis Gondii, cytomegalovirus (CMV), Herpes Simplex Virus 1, Epstein Barr Virus and mycoplasma pneumoniae) in newborn heel prick samples of 1679 ADHD cases and 2948 matching controls as part of the iPSYCH Danish case-cohort study. We found an association between high anti-CMV (OR 1.30, 95 % CI [1.09,1.55], p = 0.015) and anti-mycoplasma (OR 1.30, 95 % CI [1.07,1.59], p = 0.037) signal and those newborns later being diagnosed with ADHD. The risk estimate remained increased when controlling for ADHD polygenic risk score as well as penicillin prescriptions. We saw a dose-response association with the amount of positive anti-microorganism titers increasing the risk of being diagnosed with ADHD later in life (p = 0.01 for the trend), suggesting that the more activated the immune system is prior to or at birth, the higher the risk is for a later diagnosis with ADHD. If the associations are causal, they emphasize the importance of a healthy life style during pregnancy to reduce the risk of infections when pregnant and the associated risks for the child.

Smoking during pregnancy and risk of multiple sclerosis in offspring and mother: A Danish nationwide register-based cohort study.

BACKGROUND: The association between intra-uterine exposure to maternal smoking and risk of multiple sclerosis (MS) has been little studied and with conflicting results. OBJECTIVE: To examine the risk of MS in offspring exposed intra-uterine to maternal smoking. In addition, to re-examine prior observations of an elevated risk of MS among smokers, assuming that self-reported smoking during pregnancy reflects the woman's general smoking habits. METHODS: The study cohort included all Danish women, pregnant in the period 1991-2018, (n = 789,299) and singletons from these pregnancies (n = 879,135). Nationwide information on maternal smoking during pregnancy and MS cases in the study cohort were obtained from the Medical Birth Register and the National Patient Register. Cox regression analysis was used to estimate hazard ratios (HRs) for the association between smoking and MS risk. RESULTS: Women who smoked during pregnancy had a 42% increased risk of developing MS compared with non-smoking women (HR = 1.42 (1.32-1.52), n = 1,296). The risk of MS among singletons of women who smoked during pregnancy was 38% higher than that among singletons born to non-smoking women (HR = 1.38 (1.08-1.76), n = 110). CONCLUSION: Our observations add further to the evidence implicating smoking in the development of MS and suggest that intra-uterine exposure to tobacco smoke may increase MS risk.

Circulating apoE4 protein levels from dried blood spots predict cognitive function in a large population-based survey setting.

INTRODUCTION: The apolipoprotein E (APOE) ε4 allele carries risk for cognitive impairment, but whether the level of circulating apoE4 protein in carriers affects cognition is unclear, as is how health and lifestyle impact circulating apoE4 levels. METHODS: We assayed apoE4 protein levels in dried blood spots of 12,532 adults aged 50+. Regression analyses tested the likelihood of cognitive impairment between groups and within those with detected apoE4 protein. Predictors of circulating apoE4 were assessed. RESULTS: We detected protein binding that indicates the presence of an APOE ε4 allele in 28.4% of this group. This group was more likely to have cognitive impairment, and this risk increases with age. However, higher apoE4 levels were associated with less likelihood of cognitive impairment within this group. Antihypertensive medication predicted apoE4 protein levels. DISCUSSION: The apoE4 isoform is associated with a deficient protein and worse cognition. This association is modulated by the level of circulating apoE4 protein in ε4 carriers. HIGHLIGHTS: An assay to quantify apoE4 levels from dried blood spot samples was applied. The apoE4 protein was detected as specific binding at ≥30,000 pg/mL in 28.4% of samples. Having the apoE4 protein was associated with worse cognitive performance. Higher apoE4 protein levels in those who have it were associated with better cognition. Cardiovascular factors influenced levels of apoE4 protein.

Comparisons of 25 cerebrospinal fluid cytokines in a case-control study of 106 patients with recent-onset depression and 106 individually matched healthy subjects.

BACKGROUND: Neuroinflammation has been suggested as a contributor to the pathophysiology of depression; however, large case-control studies investigating cytokine levels in the cerebrospinal fluid (CSF) from patients with recent-onset depression by multiplex analyses are missing. METHODS: An individually matched (sex and age) prospective case-control study comparing patients with recent-onset depression to healthy controls. CSF was analyzed with the Mesoscale V-PLEX Neuroinflammation Panel 1. OUTCOMES: comparisons of analyte levels in the CSF between groups with interleukin (IL)-6 and IL-8 as primary outcomes and 23 other cytokines as secondary outcomes. RESULTS: We included 106 patients (84.0% outpatients) with recent-onset depression and 106 healthy controls. There were no significant differences in the primary outcomes IL-6 (relative mean difference (MD): 1.10; 95% confidence interval (CI) 0.93-1.30; p = 0.276) or IL-8 levels (MD: 1.05; 95% CI 0.96-1.16; p = 0.249) relative to healthy controls. IL-4 was 40% higher (MD: 1.40; 95% CI 1.14-1.72; p = 0.001), monocyte chemoattractant protein (MCP)-1 was 25% higher (MD: 1.25; 95% CI 1.06-1.47; p = 0.009) and macrophage inflammatory protein (MIP)-1ß was 16% higher (MD: 1.16; 95% CI 1.02-1.33; p = 0.025) in patients with depression relative to healthy controls. However, only IL-4 was significantly elevated after correction for multiple testing of secondary outcomes (p = 0.025). CONCLUSION: We found no significant differences in CSF levels of the co-primary outcomes IL-6 and IL-8, however, the higher CSF levels of IL-4, MCP-1 and MIP-1ß among patients with recent-onset depression compared to healthy controls indicate a potential role of these cytokines in the neuroinflammatory response to depression.

Genome-wide association study identifies 16 genomic regions associated with circulating cytokines at birth.

Circulating inflammatory markers are essential to human health and disease, and they are often dysregulated or malfunctioning in cancers as well as in cardiovascular, metabolic, immunologic and neuropsychiatric disorders. However, the genetic contribution to the physiological variation of levels of circulating inflammatory markers is largely unknown. Here we report the results of a genome-wide genetic study of blood concentration of ten cytokines, including the hitherto unexplored calcium-binding protein (S100B). The study leverages a unique sample of neonatal blood spots from 9,459 Danish subjects from the iPSYCH initiative. We estimate the SNP-heritability of marker levels as ranging from essentially zero for Erythropoietin (EPO) up to 73% for S100B. We identify and replicate 16 associated genomic regions (p < 5 x 10-9), of which four are novel. We show that the associated variants map to enhancer elements, suggesting a possible transcriptional effect of genomic variants on the cytokine levels. The identification of the genetic architecture underlying the basic levels of cytokines is likely to prompt studies investigating the relationship between cytokines and complex disease. Our results also suggest that the genetic architecture of cytokines is stable from neonatal to adult life.

Blood Biomarkers and 6- to 7-Year Childhood Outcomes Following Neonatal Encephalopathy.

OBJECTIVE: This study aimed to profile the cytokine/chemokine response from day 0 to 7 in infants (≥36 weeks of gestational age) with neonatal encephalopathy (NE) and to explore the association with long-term outcomes. STUDY DESIGN: This was a secondary study of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network randomized controlled trial of whole body hypothermia for NE. Eligible infants with moderate-severe NE were randomized to cooling or normothermia. Blood spots were collected on days 0 to 1, 2 to 4, and 6 to 7. Twenty-four cytokines/chemokines were measured using a multiplex platform. Surviving infants underwent neurodevelopmental assessment at 6 to 7 years. Primary outcome was death or moderate-severe impairment defined by any of the following: intelligence quotient <70, moderate-severe cerebral palsy (CP), blindness, hearing impairment, or epilepsy. RESULTS: Cytokine blood spots were collected from 109 participants. In total 99 of 109 (91%) were assessed at 6 to 7 years; 54 of 99 (55%) developed death/impairment. Neonates who died or were impaired had lower early regulated upon activation normal T cell expressed and secreted (RANTES) and higher day 7 monocyte chemotactic protein (MCP)-1 levels than neonates who survived without impairment. Though TNF-α levels had no association with death/impairment, higher day 0 to 1 levels were observed among neonates who died/developed CP. On multiple regression analysis adjusted for center, treatment group, sex, race, and level of hypoxic ischemic encephalopathy, higher RANTES was inversely associated with death/impairment (odds ratio (OR): 0.31, 95% confidence interval [CI]: 0.13-0.74), while day seven MCP-1 level was directly associated with death/impairment (OR: 3.70, 95% CI: 1.42-9.61). Targeted cytokine/chemokine levels demonstrated little variation with hypothermia treatment. CONCLUSION: RANTES and MCP-1 levels in the first week of life may provide potential targets for future therapies among neonates with encephalopathy. KEY POINTS: · Elevation of specific cytokines and chemokines in neonates with encephalopathy has been noted along with increased risk of neurodevelopmental impairment in infancy.. · Cytokine/chemokines at <7 days were assessed among neonates in a trial of hypothermia for HIE.. · Neonates who died or were impaired at 6 to 7 years following hypoxic-ischemic encephalopathy had lower RANTES and higher MCP-1 levels than those who survived without impairment..

Interleukin-8 dysregulation is implicated in brain dysmaturation following preterm birth.

BACKGROUND: Preterm birth is associated with dysconnectivity of structural brain networks, impaired cognition and psychiatric disease. Systemic inflammation contributes to cerebral dysconnectivity, but the immune mediators driving this association are poorly understood. We analysed information from placenta, umbilical cord and neonatal blood, and brain MRI to determine which immune mediators link perinatal systemic inflammation with dysconnectivity of structural brain networks. METHODS: Participants were 102 preterm infants (mean gestational age 29+1 weeks, range 23+3-32+0). Placental histopathology identified reaction patterns indicative of histologic chorioamnionitis (HCA), and a customized immunoassay of 24 inflammation-associated proteins selected to reflect the neonatal innate and adaptive immune response was performed from umbilical cord (n = 55) and postnatal day 5 blood samples (n = 71). Brain MRI scans were acquired at term-equivalent age (41+0 weeks [range 38+0-44+4 weeks]) and alterations in white matter connectivity were inferred from mean diffusivity and neurite density index across the white matter skeleton. RESULTS: HCA was associated with elevated concentrations of C5a, C9, CRP, IL-1ß, IL-6, IL-8 and MCP-1 in cord blood, and IL-8 concentration predicted HCA with an area under the receiver operator curve of 0.917 (95% CI 0.841 - 0.993, p < 0.001). Fourteen analytes explained 66% of the variance in the postnatal profile (BDNF, C3, C5a, C9, CRP, IL-1ß, IL-6, IL-8, IL-18, MCP-1, MIP-1ß, MMP-9, RANTES and TNF-α). Of these, IL-8 was associated with altered neurite density index across the white matter skeleton after adjustment for gestational age at birth and at scan (ß = 0.221, p = 0.037). CONCLUSIONS: These findings suggest that IL-8 dysregulation has a role in linking perinatal systemic inflammation and atypical white matter development in preterm infants.

Potential anti-EBV effects associated with elevated interleukin-21 levels: a case report.

BACKGROUND: Germinal center derived memory B cells and plasma cells constitute, in health and during EBV reactivation, the largest functional EBV reservoir. Hence, by reducing germinal center derived formation of memory B cells and plasma cells, EBV loads may be reduced. Animal and in-vitro models have shown that IL-21 can support memory B and plasma cell formation and thereby potentially contribute to EBV persistence. However, IL-21 also displays anti-viral effects, as mice models have shown that CD4+ T cell produced IL-21 is critical for the differentiation, function and survival of anti-viral CD8+ T cells able to contain chronic virus infections. CASE PRESENTATION: We present immunological work-up (flow-cytometry, ELISA and genetics) related to a patient suffering from a condition resembling B cell chronic active EBV infection, albeit with moderately elevated EBV copy numbers. No mutations in genes associated with EBV disease, common variable immunodeficiency or pertaining to the IL-21 signaling pathway (including hypermorphic IL-21 mutations) were found. Increased (> 5-fold increase 7 days post-vaccination) CD4+ T cell produced (p < 0.01) and extracellular IL-21 levels characterized our patient and coexisted with: CD8+ lymphopenia, B lymphopenia, hypogammaglobulinemia, compromised memory B cell differentiation, absent induction of B-cell lymphoma 6 protein (Bcl-6) dependent peripheral follicular helper T cells (pTFH, p = 0.01), reduced frequencies of peripheral CD4+ Bcl-6+ T cells (p = 0.05), compromised plasmablast differentiation (reduced protein vaccine responses (p < 0.001) as well as reduced Treg frequencies. Supporting IL-21 mediated suppression of pTFH formation, pTFH and CD4+ IL-21+ frequencies were strongly inversely correlated, prior to and after vaccination, in the patient and in controls, Spearman's rho: - 0.86, p < 0.001. CONCLUSIONS: To the best of our knowledge, this is the first report of elevated CD4+ IL-21+ T cell frequencies in human EBV disease. IL-21 overproduction may, apart from driving T cell mediated anti-EBV responses, disrupt germinal center derived memory B cell and plasma cell formation, and thereby contribute to EBV disease control.

Smoking, disease characteristics and serum cytokine levels in patients with primary Sjögren's syndrome.

Smoking affects several disease processes. Epidemiological studies have previously found a negative association between primary Sjögren's syndrome (pSS) and smoking. The aim of this study was to examine whether markers of disease activity and cytokine expression in pSS patients differ between ever and never smokers. Fifty-one consecutive pSS patients and 33 population controls were included in the study. Clinical and standard laboratory parameters were registered. Serum cytokines (IL-1ß, IL-2, IL-3, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17, IL-18, IL-33, IFN-α, IFN-γ, TNF-α, EGF, BAFF, Fas-ligand, RANTES, TGF-ß1) were assessed. A positive lip biopsy was less prevalent among ever smoking patients compared to never smokers (81 vs 100%; p = 0.03). However, except for TNF-α, which was higher in ever smokers, no differences in cytokine levels were found when comparing ever and never smoking pSS patients. Furthermore, no significant differences were found between ever and never smoking patients in the ESSDAI total score, IgG levels, or complement levels. However, IL-6, IL-12, IL-17 and IL-18 were significantly increased in pSS patients compared to controls. In this study, a negative association between ever smoking and positive lip biopsy was found, confirming previous reports. Expected differences in cytokine levels compared to controls were noted, but no major differences were found between ever and never smoking pSS patients. Taking into account the negative association between pSS diagnosis and smoking in epidemiological studies, possible explanations include a local effect of smoking on salivary glands rather than systemic effects by cigarette smoke.

Neonatal levels of adiponectin, interleukin-10 and interleukin-12 are associated with the risk of developing type 1 diabetes in childhood and adolescence: A nationwide Danish case-control study.

BACKGROUND/AIM: An in-depth understanding of the early phase of type 1 diabetes (T1D) pathogenesis is important for targeting primary prevention. We examined if 14 preselected mediators of immune responses differed in neonates that later developed T1D compared to control neonates. METHODS: The study is a case-control study with a 1:2 matching. The individuals were born between 1981 through 2002. Cases were validated using the National Patient Register and the Danish Childhood Diabetes Register. Interleukin(IL)-1ß, IL-4, IL-6, IL-8, IL-10, IL-12p70, interferon gamma, tumor necrosis factor alpha, transforming growth factor beta 1 (active form), leptin, adiponectin, c-reactive protein, mannose-binding lectin and soluble triggering receptor expressed on myeloid cells-1 were measured by using a flowmetric Luminex xMAP® technology. We tested two models both including a number of possible confounders. In the first model (model 1) we also adjusted for HLA-DQB1 genotype. A total of 1930 groups of assay-matched cases and controls (4746 individuals) were included in the statistical analyses. RESULTS: Adiponectin was negatively associated with later risk of T1D in both models (relative change (RC), model 1: 0.95, P=0.046 and model 2: 0.95, P=0.006). IL-10 and IL-12 were both positively associated with T1D risk in the model 2 (RC, 1.19, P=0.006 and 1.07, P=0.02, respectively)-these results were borderline significant in model 1, but showed the same direction as the results from model 2. CONCLUSIONS: Our results indicate that specific immunological signatures are already present at time of birth in children developing T1D before the age of 18years.

Levels of soluble TREM-1 in children with newly diagnosed type 1 diabetes and their siblings without type 1 diabetes: a Danish case-control study.

BACKGROUND: Type 1 diabetes (T1D) is an organ-specific autoimmune disease with an increase in incidence worldwide including Denmark. The triggering receptor expressed on myeloid cells-1 (TREM-1) is a potent amplifier of pro-inflammatory responses and has been linked to autoimmunity, severe psychiatric disorders, sepsis, and cancer. HYPOTHESIS: Our primary hypothesis was that levels of soluble TREM-1 (sTREM-1) differed between newly diagnosed children with T1D and their siblings without T1D. METHODS: Since 1996, the Danish Childhood Diabetes Register has collected data on all patients who have developed T1D before the age of 18 years. Four hundred and eighty-one patients and 478 siblings with measurements of sTREM-1-blood samples were taken within 3 months after onset-were available for statistical analyses. Sample period was from 1997 through 2005. A robust log-normal regression model was used, which takes into account that measurements are left censored and accounts for correlation within siblings from the same family. RESULTS: In the multiple regression model (case status, gender, age, HLA-risk, season, and period of sampling), levels of sTREM-1 were found to be significantly higher in patients (relative change [95%CI], 1.5 [1.1; 2.2],P = 0.02), but after adjustment for multiple testing our result was no longer statistically significant (P adjust = 0.1). We observed a statistical significant temporal increase in levels of sTREM-1. CONCLUSION: Our results need to be replicated by independent studies, but our study suggests that the TREM-1 pathway may have a role in T1D pathogenesis.

Early Elevation in Interleukin-6 is Associated with Reduced Growth in Extremely Low Birth Weight Infants.

Objective To determine whether reduced growth velocity (GV) in extremely low birth weight infants is preceded by elevated inflammatory cytokines. Study Design GV was determined at 36 weeks' postmenstrual age (PMA) in 768 infants 401 to 1,000 g birth weight (BW). Association between blood cytokines measured through day of life 21 and GV was explored using linear regression models that adjusted for late-onset sepsis (LOS), BW, small for gestational age (SGA), gender, race, energy intake, and center. Results Serum interleukin-6 (IL-6) was increased at days 14 and 21 in LOS infants. LOS was associated with reduced energy intake and GV for weight (weight-GV) at 36 weeks' PMA. Linear regression analysis controlling for LOS and energy intake showed significant relationships between increased IL-6 at days 14 and 21 with reduced weight-GV at 36 weeks' PMA (p < 0.0001). The relationship between day 21 IL-6 and weight-GV was not associated with LOS (p = 0.12) when controlling for BW and energy intake. Both BW (p = 0.02) and energy intake (p = 0.003) influenced the relationship between day 14 IL-6 and weight-GV. Conclusion IL-6 elevation during the first month of life is associated with lower weight-GV at 36 weeks' PMA and may have a direct effect upon energy balance and postnatal growth.

Blood Cytokine Profiles Associated with Distinct Patterns of Bronchopulmonary Dysplasia among Extremely Low Birth Weight Infants.

OBJECTIVE: To explore differences in blood cytokine profiles among distinct bronchopulmonary dysplasia (BPD) patterns. STUDY DESIGN: We evaluated blood spots collected from 943 infants born at ≤1000 g and surviving to 28 days on postnatal days 1, 3, 7, 14, and 21 for 25 cytokines. Infants were assigned to the following lung disease patterns: (1) no lung disease (NLD); (2) respiratory distress syndrome without BPD; (3) classic BPD (persistent exposure to supplemental oxygen until 28 days of age); or (4) atypical BPD (period without supplemental oxygen before 28 days). Median cytokine levels for infants with BPD were compared with the IQR of results among infants with NLD. RESULTS: The distribution of enrolled infants by group was as follows: 69 (NLD), 73 (respiratory distress syndrome), 381 (classic BPD), and 160 (atypical BPD). The remaining 260 infants could not be classified because of missing data (104) or not fitting a predefined pattern (156). Median levels of 3 cytokines (elevated interleukin [IL]-8, matrix metalloproteinase-9; decreased granulocyte macrophage colony-stimulating factor) fell outside the IQR for at least 2 time points in both infants with atypical and classic BPD. Profiles of 7 cytokines (IL-6, IL-10, IL-18, macrophage inflammatory protein-1α, C-reactive protein, brain-derived neurotrophic factor, regulated on activation, normal T cell expressed and secreted) differed between infants with classic and atypical BPD. CONCLUSIONS: Blood cytokine profiles may differ between infants developing classic and atypical BPD. These dissimilarities suggest the possibility that differing mechanisms could explain the varied patterns of pathophysiology of lung disease in extremely premature infants.

Cytokines associated with necrotizing enterocolitis in extremely-low-birth-weight infants.

BACKGROUND: The goal was to identify cytokines associated with necrotizing enterocolitis (NEC). Based on our earlier reports of decreased tissue expression of transforming growth factor (TGF)-ß, we hypothesized that infants with NEC also have low blood TGF-ß levels. We further hypothesized that because fetal inflammation increases the risk of NEC, infants who develop NEC have elevated blood cytokine levels in early neonatal period. METHODS: Data on 104 extremely-low-birth-weight infants with NEC and 893 without NEC from 17 centers were analyzed. Clinical information was correlated with blood cytokine levels on postnatal day 1 (D1), D3, D7, D14, and D21. RESULTS: Male gender, non-Caucasian/non-African American ethnicity, sepsis, lower blood TGF-ß and interleukin (IL)-2 levels, and higher IL-8 levels were associated with NEC. The NEC group had lower TGF-ß levels than controls since D1. The diagnosis of NEC was associated with elevated IL-1ß, IL-6, IL-8, IL-10, monocyte chemoattractant protein-1/CC-motif ligand-2, macrophage inflammatory protein-1ß/CC-motif ligand-3, and C-reactive protein. CONCLUSION: Clinical characteristics, such as gender and ethnicity, and low blood TGF-ß levels are associated with higher risk of NEC. Infants who developed NEC did not start with high blood levels of inflammatory cytokines, but these rose mainly after the onset of NEC.

Maternal pre-pregnancy and prenatal penicillin, neonatal inflammation and growth factors are associated to ADHD in the offspring.

Background: The etiology for Attention Deficit Hyperactivity Disorder (ADHD) is generally unknown, but both genetics, biology and environment have been shown to increase the risk. The purpose of this study was to explore the prenatal risk factors, especially maternal antibiotics consumed before and during pregnancy, for the offspring for later being diagnosed with ADHD, and to find associations with neonatal biomarkers. Methods: We included new-borns from the CODIBINE study, 465 children were ADHD cases and 10 954 children were controls. Ten biomarkers reflecting inflammation, neonatal stress, and/or neurologic development or damage were measured in dried blood spot samples drawn 2-3 days after birth. Maternal and child prescriptions of medication, birth data, and disorder codes were included in the statistical analyses. Results: We found that maternal penicillin prescriptions until 2 years before birth increased the risk for offspring ADHD. The risk was higher with multiple prescriptions, both before and during pregnancy. Cases with maternal penicillin prescriptions had lower neonatal levels of epidermal growth factor (EGF) and soluble Tumor Necrosis Factor Receptor I (sTNF RI). Maternal prescriptions for psychotropic medication have, as expected, the highest correlation to offspring ADHD, but we found no differences in biomarkers in this group. Conclusion: The fact that the offspring risk for ADHD was increased also with pre-pregnancy prescriptions of penicillin, indicates that it is not the penicillin that is the direct cause of the adverse effects. The significant differences in biomarkers strengthens the findings, as these could not be associated to other factors than maternal penicillin and offspring ADHD.

Assessment of circulating apoE4 levels from dried blood spot samples in a large survey setting.

INTRODUCTION: The apolipoprotein E (APOE) ε4 allele is associated with high risk for Alzheimer's disease. It is unclear whether individual levels of the circulating apoE4 protein in ε4 carriers confer additional risk. Measuring apoE4 protein levels from dried blood spots (DBS) has the potential to provide information on genetic status as well as circulating levels and to include these measures in large survey settings. METHODS: We developed a multiplex immunoassay to detect apoE4 protein levels in DBS from 15,974 participants, aged 50+ from Wave 6 of the Survey of Health, Ageing and Retirement in Europe (SHARE). RESULTS: The apoE4 protein signal was presented in two separable distributions. One distribution corresponded to carriers of at least one copy of the ε4 allele. Fieldwork cofounders affected protein levels but did not explain individual differences. DISCUSSION: Future research should investigate how genotype and apoE4 level interact with lifestyle and other variables to impact cognitive aging.