General intelligence is associated with subclinical inflammation in Nepalese children: A population-based plasma proteomics study

Microbiome function and neurodevelopment in Black infants: vitamin B12 emerges as a key factor

The early life gut microbiome affects the developing brain, and therefore may serve as a target to support neurodevelopment of children living in stressful and under-resourced environments, such as Black youth living on the South Side of Chicago, for whom we observe racial disparities in health. Microbiome compositions/functions key to multiple neurodevelopmental facets have not been studied in Black children, a vulnerable population due to racial disparities in health; thus, a subsample of Black infants living in urban, low-income neighborhoods whose mothers participated in a prenatal nutrition study were recruited for testing associations between composition and function of the gut microbiome (16S rRNA gene sequencing, shotgun metagenomics, and targeted metabolomics of fecal samples) and neurodevelopment (developmental testing, maternal report of temperament, and observed stress regulation). Two microbiome community types, defined by high Lachnospiraceae or Enterobacteriaceae abundance, were discovered in this cohort from 16S rRNA gene sequencing analysis; the Enterobacteriaceae-dominant community type was significantly negatively associated with cognition and language scores, specifically in male children. Vitamin B12 biosynthesis emerged as a key microbiome function from shotgun metagenomics sequencing analysis, showing positive associations with all measured developmental skills (i.e., cognition, language, motor, surgency, effortful control, and observed stress regulation). Blautia spp. also were identified as substantial contributors of important microbiome functions, including vitamin B12 biosynthesis and related vitamin B12-dependent microbiome functions, anti-inflammatory microbial surface antigens, competitive mechanisms against pathobionts, and production of antioxidants. The results are promising with respect to the potential for exploring therapeutic candidates, such as vitamin B12 nutritional or Blautia spp. probiotic supplementation, to support the neurodevelopment of infants at risk for experiencing racial disparities in health.

Elevated CRP and TNF-α levels are associated with blunted neural oscillations serving fluid intelligence

INTRODUCTION

Inflammatory processes help protect the body from potential threats such as bacterial or viral invasions. However, when such inflammatory processes become chronically engaged, synaptic impairments and neuronal cell death may occur. In particular, persistently high levels of C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-α) have been linked to deficits in cognition and several psychiatric disorders. Higher-order cognitive processes such as fluid intelligence (Gf) are thought to be particularly vulnerable to persistent inflammation. Herein, we investigated the relationship between elevated CRP and TNF-α and the neural oscillatory dynamics serving Gf.

METHODS

Seventy adults between the ages of 20-66 years (Mean = 45.17 years, SD = 16.29, 21.4% female) completed an abstract reasoning task that probes Gf during magnetoencephalography (MEG) and provided a blood sample for inflammatory marker analysis. MEG data were imaged in the time-frequency domain, and whole-brain regressions were conducted using each individual's plasma CRP and TNF-α concentrations per oscillatory response, controlling for age, BMI, and education.

RESULTS

CRP and TNF-α levels were significantly associated with region-specific neural oscillatory responses. In particular, elevated CRP concentrations were associated with altered gamma activity in the right inferior frontal gyrus and right cerebellum. In contrast, elevated TNF-α levels scaled with alpha/beta oscillations in the left anterior cingulate and left middle temporal, and gamma activity in the left intraparietal sulcus.

DISCUSSION

Elevated inflammatory markers such as CRP and TNF-α were associated with aberrant neural oscillations in regions important for Gf. Linking inflammatory markers with regional neural oscillations may hold promise in identifying mechanisms of cognitive and psychiatric disorders.

Association of indoor dust microbiota with cognitive function and behavior in preschool-aged children

BACKGROUND

Childhood cognitive development depends on neuroimmune interactions. Immunomodulation by early-life microbial exposure may influence neuropsychological function. In this study, we investigate the association between residential indoor microbiota and cognition and behavior among preschoolers.

RESULTS

Indoor-settled dust bacterial and fungal characteristics were assessed using 16S and ITS amplicon sequencing (microbial diversity) and qPCR measurements (microbial loads). Child behavior was assessed using four scales: peer relationship, emotional, conduct, and hyperactivity was assessed by the Strengths and Difficulties Questionnaire (SDQ). Cognitive function was assessed using four tasks of the Cambridge Neuropsychological Test Automated Battery (CANTAB) software. The first two tasks were designed to assess attention and psychomotor speed (Motor Screening (MOT) and Big/Little Circle (BLC)) and the last two to evaluate the child's visual recognition/working memory (Spatial Span (SSP) and Delayed Matching to Sample (DMS)). Among the 172 included children (age 4-6 years), we observed a 51% (95%CI;75%;9%) lower odds of children scoring not normal for hyperactivity and a decrease of 3.20% (95%CI, -6.01%; -0.30%) in BLC response time, for every IQR increase in fungal Shannon diversity. Contrarily, microbial loads were directly associated with SDQ scales and response time. For example, a 2-fold increase in Gram-positive bacterial load was associated with 70% (95%CI 18%; 156%) higher odds of scoring not normal for hyperactivity and an increase of 5.17% (95%CI 0.87%; 9.65%) in DMS response time.

CONCLUSIONS

Our findings show that early-life exposure to diverse indoor fungal communities is associated with better behavioral and cognitive outcomes, whereas higher indoor microbial load was associated with worse outcomes. Video Abstract.

The association of systemic inflammation and cognitive functions of pre-school aged children residing in a Schistosoma haematobium endemic area in Zimbabwe

Background

Cognitive function is negatively impacted by schistosomiasis and might be caused by systemic inflammation which has been hypothesized to be one of the mechanisms driving cognitive decline, This study explored the association of systemic inflammatory biomarkers; interleukin (IL)-10, IL-6, IL-17, transforming growth factor (TGF-β), tumor necrosis factor (TNF-α), C-reactive protein (CRP) and hematological parameters with cognitive performance of preschool-aged children (PSAC) from an Schistosoma haematobium endemic area.

Methods

The Griffith III tool was used to measure the cognitive performance of 136 PSAC. Whole blood and sera were collected and used to quantify levels of IL-10, TNF-α, IL-6, TGF-β, IL-17 A and CRP using the enzyme-linked immunosorbent assay and hematological parameters using the hematology analyzer. Spearman correlation analysis was used to determine the relationship between each inflammatory biomarker and cognitive performance. Multivariate logistic regression analysis was used to determine whether systemic inflammation due to S. haematobium infection affected cognitive performance in PSAC.

Results

Higher levels of TNF-α and IL-6, were correlated with lower performance in the Foundations of Learning domain (r = -0.30; p < 0.001 and r = -0.26; p < 0.001), respectively. Low cognitive performance in the Eye-Hand-Coordination Domain was observed in PSAC with high levels of the following inflammatory biomarkers that showed negative correlations to performance; TNF-α (r = -0.26; p < 0.001), IL-6 (r = -0.29; p < 0.001), IL-10 (r = -0.18; p < 0.04), WBC (r = -0.29; p < 0.001), neutrophils (r = -0.21; p = 0.01) and lymphocytes (r = -0.25; p = 0.003) The General Development Domain correlated with TNF-α (r = -0.28; p < 0.001) and IL-6 (r = -0.30; p < 0.001). TGF-β, L-17A and MXD had no significant correlations to performance in any of the cognitive domains. The overall general development of PSAC was negatively impacted by S. haematobium infections (OR = 7.6; p = 0.008) and (OR = 5.6; p = 0.03) where the PSAC had higher levels of TNF-α and IL-6 respectively.

Conclusion

Systemic inflammation and S. haematobium infections are negatively associated with cognitive function. We recommend the inclusion of PSAC into mass drug treatment programs.

Cognitive Outcomes in Children With Conditions Affecting the Small Intestine: A Systematic Review and Meta-analysis

OBJECTIVES

The aim of the study was to assess cognitive outcomes in children with intestinal failure (IF) and children at high risk of IF with conditions affecting the small intestine requiring parenteral nutrition.

METHODS

EMBASE, Cochrane, Web of Science, Google Scholar, MEDLINE, and PsycINFO were searched from inception to October 2020. Studies were included constituting original data on developmental quotient (DQ), intelligence quotient (IQ) and/or severe developmental delay/disability (SDD) rates assessed with standardized tests. We used appropriate standardized tools to extract data and assess study quality. We performed random effects meta-analyses to estimate pooled means of DQ/IQ and pooled SDD rates (general population mean for DQ/IQ: 100, for percentage with SDD: 1.8%) for 4 groups: IF, surgical necrotizing enterocolitis (NEC), abdominal wall defects (AWD), and midgut malformations (MM). Associations of patient characteristics with DQ/IQ were evaluated with meta-regressions.

RESULTS

Thirty studies met the inclusion criteria. The pooled mean DQ/IQ for IF, NEC, AWD, and MM were 86.8, 83.3, 96.6, and 99.5, respectively. The pooled SDD rates for IF, NEC, AWD and MM were 28.6%, 32.8%, 8.5%, and 3.7%, respectively. Meta-regressions indicated that lower gestational age, longer hospital stay, and higher number of surgeries but not parenteral nutrition duration, were associated with lower DQ/IQ.

CONCLUSIONS

Adverse developmental outcomes are common in children with IF and NEC, and to a much lesser extent in children with AWD and MM. It is important to monitor cognitive development in children with conditions affecting the small intestine and to explore avenues for prevention and remediation.

COVID-19 threatens maternal mental health and infant development: possible paths from stress and isolation to adverse outcomes and a call for research and practice

The COVID-19 pandemic exposed mothers to stress and social isolation during the pre- and post-natal periods. The deleterious effects of stress on both pregnant women and their infants are well documented, with research suggesting that effects are exacerbated by reduced social support. In this brief report, we summarize evidence linking stress and social isolation to negative outcomes for mothers and infants and present a conceptual model featuring inflammation as a driving mechanism. There is strong evidence that the coronavirus pandemic will affect mothers and infants through immune pathways that, in previous research, have been shown to link stress and social isolation during the pre- and post-natal periods with deficits in maternal mental health and infant well-being and development across developmental stages. We close with recommendations for novel research, policy changes, and integrated clinical care that can address these biological threats to infants and mothers while leveraging the anti-inflammatory effects of social support.

Circulating inflammatory biomarkers and academic performance in adolescents: DADOS study

OBJECTIVE

The present study aimed (1) to examine the association between circulating inflammatory biomarkers and academic performance in adolescents, and (2) to identify the ability of circulating inflammatory biomarkers to predict low academic performance.

METHODS

A total of 244 adolescents (13.9±0.3 years, 112 girls) from the DADOS study were included in the analysis. Four inflammatory biomarkers were quantified: white blood cell (WBC) count, interleukin-6, tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP). Academic performance was assessed through academic grades and the Spanish version of the Science Research Associates Test of Educational Abilities.

RESULTS

TNF-α was inversely associated with math, Spanish and grade point average (β ranging from -0.166 to -0.124; all p<0.05), while CRP was inversely associated with verbal ability (β = -0.128; p<0.05). Overall, receiver operating characteristic (ROC) curves analyses showed discriminatory ability of WBC and TNF-α in identifying low academic performance (all p<0.05). Moreover, logistic regression analyses indicated that students with levels of WBC and TNF-α above the ROC cut-offs values showed between 78% to 87% increased likelihood of lower academic performance (p<0.05).

CONCLUSIONS

Our findings suggested that some circulating inflammatory biomarkers were associated with academic performance in adolescents. Further larger longitudinal and interventional studies are needed to clarify the short-term and long-term relationship between inflammation and academic performance in youths.

The Role of Genetic Variation of BMI, Body Composition, and Fat Distribution for Mental Traits and Disorders: A Look-Up and Mendelian Randomization Study

Anthropometric traits and mental disorders or traits are known to be associated clinically and to show genetic overlap. We aimed to identify genetic variants with relevance for mental disorders/traits and either (i) body mass index (or obesity), (ii) body composition, (and/or) (iii) body fat distribution. We performed a look-up analysis of 1,005 genome-wide significant SNPs for BMI, body composition, and body fat distribution in 15 mental disorders/traits. We identified 40 independent loci with one or more SNPs fulfilling our threshold significance criterion (P < 4.98 × 10^–5) for the mental phenotypes. The majority of loci was associated with schizophrenia, educational attainment, and/or intelligence. Fewer associations were found for bipolar disorder, neuroticism, attention deficit/hyperactivity disorder, major depressive disorder, depressive symptoms, and well-being. Unique associations with measures of body fat distribution adjusted for BMI were identified at five loci only. To investigate the potential causality between body fat distribution and schizophrenia, we performed two-sample Mendelian randomization analyses. We found no causal effect of body fat distribution on schizophrenia and vice versa. In conclusion, we identified 40 loci which may contribute to genetic overlaps between mental disorders/traits and BMI and/or shape related phenotypes. The majority of loci identified for body composition overlapped with BMI loci, thus suggesting pleiotropic effects.

Effect of prebiotic and probiotic supplementation on neurodevelopment in preterm very low birth weight infants: findings from a meta-analysis

BACKGROUND

Preterm very low birth weight (VLBW) infants are at risk of gut dysbiosis and neurodevelopmental deficits. Prebiotics and probiotics may modulate gut microbiota and influence brain functions. This review synthesizes literature on effect of prebiotic and/or probiotic supplementation in preterm VLBW on their neurodevelopmental outcomes.

METHODS

Search was done using PubMed and CENTRAL. Randomized controlled trials (RCTs) in preterm infants (<37 weeks gestation) and/or infants with birth weight <1500 g that evaluated the effect of prebiotic and/or probiotic supplementation on neurodevelopmental outcomes were included. Weighted mean difference in cognitive and motor scores; pooled relative risks for cognitive and motor impairment, cerebral palsy, hearing, and visual impairment were estimated. Quality of evidence was assessed using the GRADE criteria.

RESULTS

Out of 275 articles identified, seven were included for review. All, except one, were done in preterms <33 weeks of gestation. Age of assessment of outcomes was ≥18-22 months of corrected age in five studies. Interventions did not decrease or increase the risk of cognitive and motor impairment, cerebral palsy, visual, and hearing impairment. Quality of evidence was "low" to "very low."

CONCLUSIONS

Limited evidence from RCTs does not demonstrate a difference in neurodevelopmental outcomes between prebiotic/probiotic treated and untreated control groups.

A point-of-care assay for alpha-1-acid glycoprotein as a diagnostic tool for rapid, mobile-based determination of inflammation

BACKGROUND

Inflammation is a key component of immune response to infections and pathogenesis of metabolic and cardiovascular diseases. Inflammatory biomarkers, including alpha-1-acid glycoprotein (AGP), are considered prognostic tools for predicting risk, monitoring response to therapy, and adjusting nutritional biomarkers for accurate interpretation. Serum is considered a primary source of biomarkers; urine and saliva are increasingly being explored and utilized as rapidly accessible, noninvasive biofluids requiring minimal sample processing and posing fewer biohazard risks.

METHODS

A lateral flow immunoassay was developed for an established mobile-based platform to quantify AGP in human serum, urine, and saliva. Assay performance was assessed with purified AGP in buffer, diluted human serum samples (n = 16) banked from a trial in people living with HIV, and saliva and urine (n = 15 each) from healthy participants. Reference methods were conventional clinical chemistry analyzer or commercial ELISA. Bootstrap analysis was used to train and validate sample calibration.

FINDINGS

The correlation between the assay and reference method for serum was 0.97 (P < 0.001). Mean (95% CI) best fit line slope was 1.0 (0.88, 1.15) and intercept was -0.003 (-0.08, 0.09). The correlation for urine was 0.93, and for saliva was 0.97 (both P < 0.001). The median CV for the LFIA for AGP in buffer was 13.2% and for all samples was 28.7%.

INTERPRETATION

The performance of the assay indicated potential use as a rapid, low sample volume input, and easy method to quantify AGP that can be licensed and adopted by commercial manufacturers for regulatory approvals and production. This has future applications for determining inflammatory status either alone or in conjunction with other inflammatory proteins such as C-reactive protein for prognostic, monitoring, or nutritional status applications, including large-scale country level surveys conducted by the DHS and those recommended by the WHO.

Inflammatory biomarkers and brain health indicators in children with overweight and obesity: The ActiveBrains project

INTRODUCTION

Chronic inflammation plays an important role on the pathogenesis of several cardiovascular and metabolic diseases, as well as on brain function and behaviour. The aim of the present study was to examine the associations between inflammatory biomarkers and a wide range of brain health indicators (i.e., academic performance, executive function, behavioural and emotional functioning, and brain volume) in children with overweight/obesity.

METHODS

A total of 107 children (10.0 ± 1.1 years, 41% girls) from the ActiveBrains project were included in the analysis. Five inflammatory biomarkers were analysed in plasma: white blood cell (WBC) count, interleukin-6 (IL-6), interleukin-1β, tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP). Academic performance was assessed by Woodcock-Muñoz Tests of Achievement. Executive function was assessed through the Design Fluency Test for cognitive flexibility, the Stroop test for cognitive inhibition, and the Delayed Non-Match-to-Sample task for working memory. Behavioural and emotional functioning was evaluated through the Behavior Assessment System for Children (BASC) questionnaire. Total and regional brain volume was assessed by magnetic resonance imaging.

RESULTS

IL-6 was inversely associated with adaptive skills (β = -0.228; p = 0.030), while TNF-α was related to mathematics (β = -0.198; p = 0.034). In addition, CRP was positively associated with externalizing (β = 0.246; p = 0.046) and internalizing problems (β = 0.234; p = 0.039), as well as the behavioural symptoms index (β = 0.236; p = 0.047). However, these significant associations disappeared after multiple comparisons correction. Inflammatory biomarkers were not associated with executive function and total brain volumes. Regarding regional brain analyses, WBC was positively associated with gray matter volume in the left middle temporal gyrus (β = 0.387; p < 0.001, k = 44), and CRP was positively associated with gray matter volume in the right superior temporal gyrus (β = 0.439; p < 0.001, k = 29). Additionally, when adjusting by total brain volume, CRP was positively associated with gray matter volume in the right supplementary motor cortex (β = 0.453; p < 0.001, k = 51). Moreover, both, IL-6 (β = 0.366; p < 0.001, k = 81) and TNF-α (β = 0.368; p < 0.001, k = 62) were positively associated with white matter volume around the right inferior frontal gyrus pars opercularis, while CRP was inversely associated with white matter volume around the left superior frontal gyrus (β = -0.482; p < 0.001, k = 82). After adjusting by total brain volume, CRP was also inversely associated with white matter volume in 3 additional clusters (β ranging from -0.473 to -0.404; p < 0.001, k = 87).

CONCLUSIONS

Inflammation was slightly associated with brain health (i.e., academic performance, behavioural and emotional functioning and regional brain volume) in children with overweight or obesity. Further larger longitudinal and interventional studies are warranted to elucidate the short-term and long-term effect of systemic low-grade inflammation on children's brain health.

Rainer Gross Award Lecture 2018: The Childhood Plasma Proteome: Discovering its Applications in Public Health Nutrition

Millions of children have multiple nutritional deficiencies, threatening their optimal growth, development, and quality of life. Revealing the magnitude and underlying biology of malnutrition from a greatly expanded set of practical biomarkers will be critical for developing appropriately targeted and evaluated interventions. However, our abilities to reveal and quantify the many forms of malnutrition, other than by anthropometry and occasional use of biochemical indicators, remain limited. Plasma proteomics holds great promise as a basis for developing novel biomarkers to facilitate assessment of growth, micronutrient status, inflammation, and other health status of populations while also providing biological insight into causes and adverse consequences of malnutrition. Discovery-driven plasma proteomics has been shown to reveal functional biomarkers of nutritional and health status, identifying clusters of protein biomarkers from which field-friendly, comprehensive, and low-cost methods could be developed for assessing populations. In this brief review, we summarize several key discoveries to date and discuss potential public health applications of proteomics-based biomarkers in reporting the extent and metabolic features of undernutrition in low-resource settings.

Plasma proteomics and the paediatric patient

INTRODUCTION

Plasma proteomics has been extensively utilized for studies that investigate various disease settings (e.g. cardiovascular disease), as well as to monitor the effect of pharmaceuticals on the plasma proteome (e.g. chemotherapy). However, plasma proteomic studies focusing on children represent a very small proportion of the plasma proteomic studies completed to date. Early disease detection and prevention is critical in pediatrics, as children must live with the disease outcomes for many years and often carry negative outcomes into adulthood. Pediatrics represents an area of plasma proteomics that is about to undergo a significant expansion. Areas covered: This review is based on a PubMed search focusing on five keywords that are plasma, biomarkers, pediatric, proteomics, and children. It is a comprehensive summary of plasma proteomic studies specific to the pediatric patient and discusses aspects such as the clinical setting, sample size, methodological approaches and outlines the significance of the findings. Expert commentary: Plasma proteomics is expanding significantly as a result of major advancements in proteomic technology. This is in synergy with the growing focus on true early disease detection and prevention in early life. We are about to see a new era of advanced medical science built from pediatric proteomics.

The Impact of Systemic Inflammation on Neurodevelopment

Inflammatory mediators affect the brain during development. Neurodevelopmental disorders such as autism spectrum disorders, cognitive impairment, cerebral palsy, epilepsy, and schizophrenia have been linked to early life inflammation. Recent advances have shown the effects of systemic inflammation on children's neurodevelopment. We discuss the potential mechanisms by which inflammatory molecules can exert their effects on the developing brain and consider the roles of MHC class I molecules, the HPA axis, glial cells, and monoamine metabolism. Methods to prevent the effects of cytokine imbalance may lead to the development of new therapeutics for neuropsychiatric disorders. Future research should focus on identifying at-risk individuals and early effective interventions to prevent long-term neurodevelopmental disabilities.

Novel Plasma Proteins in Nepalese School-aged Children are Associated with a Small Head Size at Birth

Fetal growth restriction increases the risk of poor childhood growth and development and chronic disease in adulthood. Yet, little is known about biological pathways that mediate the long-lasting effects of suboptimal intrauterine growth. We explored the plasma proteome in a cohort of 500 Nepalese children 6–8 years of age to identify plasma proteins associated with multiple anthropometric size indicators at birth. Among 982 proteins analyzed, no proteins differed by birth weight, length, or weight-for-length indicators. However, 25 proteins were differentially abundant in children with a small vs normal head circumference at birth (<−2 vs. ≥−2 z-scores of the WHO growth standards). Angiopoietin-like 6 was 19.4% more abundant and the other 24 proteins were 7–21% less abundant in children with a small vs normal head circumference at birth, adjusted for potential confounders. The less abundant proteins included actins, actin filament organizing proteins (α-actinin, talin, filamin, cofilin, profilin, and vinculin), proteins involved in muscle contraction, and glycolytic enzymes, which were all positively correlated with each other. A novel cluster of childhood plasma proteins involved in angiogenesis and cytoskeleton dynamics was associated with a small head size at birth. The prognostic value of an altered proteomic phenotype remains to be investigated.

Plasma proteins associated with circulating carotenoids in Nepalese school-aged children

Carotenoids are naturally occurring pigments that function as vitamin A precursors, antioxidants, anti-inflammatory agents or biomarkers of recent vegetable and fruit intake, and are thus important for population health and nutritional assessment. An assay approach that measures proteins could be more technologically feasible than chromatography, thus enabling more frequent carotenoid status assessment. We explored associations between proteomic biomarkers and concentrations of 6 common dietary carotenoids (α-carotene, β-carotene, lutein/zeaxanthin, β-cryptoxanthin, and lycopene) in plasma from 500 6-8 year old Nepalese children. Samples were depleted of 6 high-abundance proteins. Plasma proteins were quantified using tandem mass spectrometry and expressed as relative abundance. Linear mixed effects models were used to determine the carotenoid:protein associations, accepting a false discovery rate of q < 0.10. We quantified 982 plasma proteins in >10% of all child samples. Among these, relative abundance of 4 were associated with β-carotene, 11 with lutein/zeaxanthin and 51 with β-cryptoxanthin. Carotenoid-associated proteins are notably involved in lipid and vitamin A transport, antioxidant function and anti-inflammatory processes. No protein biomarkers met criteria for association with α-carotene or lycopene. Plasma proteomics may offer an approach to assess functional biomarkers of carotenoid status, intake and biological function for public health application. Original maternal micronutrient trial from which data were derived as a follow-up activity was registered at ClinicalTrials.gov: NCT00115271.

Association between childhood infection, serum inflammatory markers and intelligence: findings from a population-based prospective birth cohort study

A link between infection, inflammation, neurodevelopment and adult illnesses has been proposed. The objective of this study was to examine the association between infection burden during childhood - a critical period of development for the immune and nervous systems - and subsequent systemic inflammatory markers and general intelligence. In the Avon Longitudinal Study of Parents and Children, a prospective birth cohort in England, we examined the association of exposure to infections during childhood, assessed at seven follow-ups between age 1·5 and 7·5 years, with subsequent: (1) serum interleukin 6 and C-reactive protein (CRP) levels at age 9; (2) intelligence quotient (IQ) at age 8. We also examined the relationship between inflammatory markers and IQ. Very high infection burden (90+ percentile) was associated with higher CRP levels, but this relationship was explained by body mass index (adjusted odds ratio (OR) 1·19; 95% confidence interval (CI) 0·95-1·50), maternal occupation (adjusted OR 1·23; 95% CI 0·98-1·55) and atopic disorders (adjusted OR 1·24; 95% CI 0·98-1·55). Higher CRP levels were associated with lower IQ; adjusted β = -0·79 (95% CI -1·31 to -0·27); P = 0·003. There was no strong evidence for an association between infection and IQ. The findings indicate that childhood infections do not have an independent, lasting effect on circulating inflammatory marker levels subsequently in childhood; however, elevated inflammatory markers may be harmful for intellectual development/function.

The Plasma Proteome Is Associated with Anthropometric Status of Undernourished Nepalese School-Aged Children

Background: Malnutrition affects body growth, size, and composition of children. Yet, few functional biomarkers are known to be associated with childhood morphology.

Objective: This cross-sectional study examined associations of anthropometric indicators of height, musculature, and fat mass with plasma proteins by using proteomics in a population cohort of school-aged Nepalese children.

Methods: Height, weight, midupper arm circumference (MUAC), triceps and subscapular skinfolds, upper arm muscle area (AMA), and arm fat area (AFA) were assessed in 500 children 6–8 y of age. Height-for-age z scores (HAZs), weight-for-age z scores (WAZs), and body mass index–for-age z scores (BAZs) were derived from the WHO growth reference. Relative protein abundance was quantified by using tandem mass spectrometry. Protein-anthropometry associations were evaluated by linear mixed-effects models and identified as having a false discovery rate (q) <5%.

Results: Among 982 proteins, 1, 10, 14, and 17 proteins were associated with BAZ, HAZ, MUAC, and AMA, respectively (q < 0.05). Insulin-like growth factor (IGF)-I, 2 IGF-binding proteins, and carnosinase-1 were associated with both HAZ and AMA. Proteins involved in nutrient transport, activation of innate immunity, and bone mineralization were associated with HAZ. Several extracellular matrix proteins were positively associated with AMA alone. The proteomes of MUAC and AMA substantially overlapped, whereas no proteins were associated with AFA or triceps and subscapular skinfolds. Myosin light-chain kinase, possibly reflecting leakage from muscle, was inversely associated with BAZ. The proteome of WAZ was the largest (n = 33) and most comprehensive, including proteins involved in neural development and oxidative stress response, among others.

Conclusions: Plasma proteomics confirmed known biomarkers of childhood growth and revealed novel proteins associated with lean mass in chronically undernourished children. Identified proteins may serve as candidates for assessing growth and nutritional status of children in similar undernourished settings. The antenatal micronutrient supplementation trial yielding the study cohort of children was registered at clinicaltrials.gov as NCT00115271.