Michael K. Georgieff - US grants

This is a Shannon Award providing partial support for research projects that fall short of the assigned institute's funding range but are in the margin of excellence. The Shannon award is intended to provide support to test the feasibility of the approach; develop further tests and refine research techniques; perform secondary analysis of available data sets; or conduct discrete projects that can demonstrate the PI's research capabilities or lend additional weight to an already meritorious application. Further scientific data for the CRISP System are unavailable at this time.

Postnatally acquired iron deficiency causes long-term nonhematologic (heart, brain) organ dysfunction. Up to 125,000 infants of diabetic mothers (IDM) are born each year with reduced iron stores. IDM are prone to abnormal cardiac and neurologic function in the newborn period and to long-term abnormal cognitive development We are evaluating the hypothesis that fetal iron deficiency associated with maternal diabetes mellitus may contribute to this pathophysiology in the newborn period. Tissue studies of infants of diabetic mothers demonstrate liver, brain and myocardial iron depletion at birth. These iron abnormalities are most likely due to sequestration of available fetal iron in an expanded red cell mass. Although placental transferrin receptor protein expression is increased in diabetic pregnancies, the affinity of the receptor is reduced, resulting in no apparent increase in iron transport in spite of increased fetal iron demand and fetal tissue iron deficiency. Our long-term objectives are to: 1) study the regulation of the placental iron transfer mechanism during fetal hypoxia and augmented iron demand in IDM; 2) document postnatal myocardial and neurologic sequelae of fetal iron deficiency. We hypothesize that: 1) placental transferrin receptor (TR) expression and binding affinity for transferrin are regulated by fetal iron demand and insulin; 2) fetal myocardial iron deficiency results in decreased neonatal cardiac ATP generation and reduced myocardial function; 3) fetal brain iron deficiency in IDM contributes to a higher rate of cognitive neurologic sequelae in IDM. Forty pregnant insulin-dependent diabetic women will be recruited at 36 weeks gestation. Their newborns' cord blood will be sampled for serum ferritin concentration and subsequently divided into two groups of 20: those with low ferritins and those with normal ferritins. Twenty additional age-matched infants born to non-diabetic mothers will serve as controls. Placental TR expression (immunohistochemistry), TR mRNA (Northern and dot blot) and 125I-transferrin binding (Scatchard analysis) in IDM with low ferritins will be compared to IDM with normal ferritins and to controls. The relationship of TR, TR mRNA and TR binding to duration of fetal hypoxia, and degrees of fetal hyperinsulinemia, iron demand and placental non-heme iron will be assessed in humans and guinea pigs. Structural alterations of TR in human diabetic pregnancies will be assessed. Neonatal cardiac contractility in iron-deficient IDM will be assessed by echocardiography. Iron-deficient newborn guinea pig hearts (generated by prolonged fetal hypoxia and iron deficiency) will have cytochrome c, ATP, ADP, AMP and creatine phosphate concentrations and myocardial contracti1ity measured and compared to non-hypoxic iron- sufficient controls to assess the effect of fetal iron deficiency on myocardial energy metabolism and contractility. Cognitive function (discriminative memory) of human IDM will be assessed by event-related potential (ERP) recording in the newborn period and by ERP, Bayley Scales of Infant Development, and Piaget A not B test at 18 months and compared to controls.

cognition; mental health epidemiology; iron disorder; newborn human (0-6 weeks); prenatal growth disorder; brain imaging /visualization /scanning; brain electrical activity; evoked potentials; nursing care; clinical research; human subject;

[unreadable] DESCRIPTION (provided by applicant): The primary goal of this grant proposal is to promote interdisciplinary research in neurobehavioral development at the postdoctoral level. We will target trainees who have received a Ph.D. in Child Psychology, Neuroscience or Developmental Neuroscience-related disciplines (e.g., molecular or developmental biology), as well as M.D.'s in various Pediatric disciplines, such as Neonatology, Pediatric Neurology and Child Psychiatry. The motivation behind this proposal is to foster the development of junior investigators who can integrate research and theory in human behavioral development with explication of underlying neural circuitry and neurodevelopmental processes. A long-range goal is to create a discipline we have come to call "neurobehavioral development." Clearly, knowledge of the neurobiological mechanisms underlying behavioral development would benefit those interested in a range of behavioral phenomena, and vice versa. To date there are relatively few developmental researchers who work at this interdisciplinary boundary in either basic or clinical domains. Consequently, there is a tremendous need to foster this integration among principal investigators and to support the interdisciplinary training of students. This is the mission of the Center for Neurobehavioral Development (CNBD) at the University of Minnesota, which will be home to this training grant. The CNBD accomplishes this mission by providing research space, educational colloquia and classes co-listed in multiple relevant departments, and by having a core faculty consisting of developmental, cognitive, behavioral, and basic neuroscientists working at multiple tiers of investigation in the human and in animal models. [unreadable] [unreadable]

4-Aminobutanoic Acid; 4-Aminobutyric Acid; Aminalon; Aminalone; Ammon Horn; Aspartate; Biological; Brain; Butanoic acid, 4-amino-; CRISP; Chronic; Cognitive deficits; Common Rat Strains; Computer Retrieval of Information on Scientific Projects Database; Cornu Ammonis; Creatine; Creatine Phosphate; Diet; Encephalon; Encephalons; Ethanesulfonic acid, 2-amino-; Fe element; Funding; GABA; Glutamates; Glycine, N-(aminoiminomethyl)-N-methyl-; Glycine, N-(imino(phosphonoamino)methyl)-N-methyl-; Grant; Gravid; Hippocampus; Hippocampus (Brain); Human; Human, General; Hypoxia; Hypoxic; Infant; Injury; Institution; Investigators; Iron; L-Aspartate; L-Glutamate; Mammals, Rats; Man (Taxonomy); Man, Modern; Measures; N-acetyl aspartate; N-acetyl-L-aspartate; N-acetylaspartate; NIH; NMR Spectroscopy; National Institutes of Health; National Institutes of Health (U.S.); Nerve Impulse Transmission; Nerve Transmission; Nervous System, Brain; Neurochemistry; Neuronal Transmission; Oxygen Deficiency; Patient currently pregnant; Patient pregnant NOS; Perinatal; Phosphocreatine; Phosphorylcreatine; Pregnancy not delivered; Pregnancy, gravid; Rat; Rattus; Research; Research Personnel; Research Resources; Researchers; Resources; Rest; Risk; Science of neurochemistry; Source; Spectroscopy, NMR; Tauphon; Taurine; Time; United States National Institutes of Health; day; ethanolamine phosphate; feeding; gamma-Aminobutyric Acid; hippocampal; in vivo; myelination; neurochemistry; neurotransmission; nuclear magnetic resonance spectroscopy; phosphoethanolamine; phosphorylethanolamine; postnatal; pregnant

[unreadable] DESCRIPTION (provided by applicant): The primary goal of this grant proposal is to promote interdisciplinary research in neurobehavioral development at the postdoctoral level. We will target trainees who have received a Ph.D. in Child Psychology, Neuroscience or Developmental Neuroscience-related disciplines (e.g., molecular or developmental biology), as well as M.D.'s in various Pediatric disciplines, such as Neonatology, Pediatric Neurology and Child Psychiatry. The motivation behind this proposal is to foster the development of junior investigators who can integrate research and theory in human behavioral development with explication of underlying neural circuitry and neurodevelopmental processes. A long-range goal is to create a discipline we have come to call "neurobehavioral development." Clearly, knowledge of the neurobiological mechanisms underlying behavioral development would benefit those interested in a range of behavioral phenomena, and vice versa. To date there are relatively few developmental researchers who work at this interdisciplinary boundary in either basic or clinical domains. Consequently, there is a tremendous need to foster this integration among principal investigators and to support the interdisciplinary training of students. This is the mission of the Center for Neurobehavioral Development (CNBD) at the University of Minnesota, which will be home to this training grant. The CNBD accomplishes this mission by providing research space, educational colloquia and classes co-listed in multiple relevant departments, and by having a core faculty consisting of developmental, cognitive, behavioral, and basic neuroscientists working at multiple tiers of investigation in the human and in animal models. [unreadable] [unreadable]

DESCRIPTION (provided by applicant): Iron deficiency (ID) remains one of the foremost world-wide nutrient deficiencies that affect brain development in the fetus and in children. ID affects at least 3 major aspects of early brain development: energy metabolism (especially in hippocampus (HC)), monoamine neurotransmitter homeostasis, and myelination, in turn potentially affecting behaviors such as recognition memory, procedural memory and speed of processing. In humans and dietary ID animal models, it is unclear whether structural and behavioral effects in the developing brain are due directly to a lack of iron interacting with important transcriptional, translational or post-translational processes or to indirect effects such as hypoxia (due to anemia) or perturbation of the homeostasis of other divalent cations important in brain development such as Zn, Cu or Mn. To circumvent these potential confounders and to directly assess iron's role in the development of the HC, we have generated two non-anemic genetic mouse models by conditionally altering the expression of two iron uptake transport proteins in area CA-1 of the HC. CA-1 is essential to recognition memory function and is altered metabolically, structurally and functionally in dietary ID. Model 1 relies on a CaMKinase II alpha-Cre-lox system to knock-out (KO) divalent metal transporter-1 (DMT-1), the major intracellular ferrous off-loading protein at embryonic day (E) 18 prior to CA-1 differentiation. This animal has been bred, is non-anemic and needs to be characterized from genotypic and iron phenotypic perspective. Model 2 uses a doxycycline induced (tetracycline transactivator) dominant-negative (DN) approach to functionally reduce the activity of transferrin receptor-1 (TfR-1), the major neuronal transmembrane iron uptake protein, in GA-1 pyramidal neurons. The parent lineages for this animal have been generated and are ready to be bred. The offspring will need to be genotypically and phenotypically characterized. The Specific Aims of this R-21 are to 1) confirm the absence of DMT-1 protein and mRNA, establish the hippocampal iron status and assess the behavioral phenotype of the conditional DMT-1 KO animal, and 2) to breed, confirm the mutation of TfR-1 in HC, establish the CA-1 iron status and assess the behavioral phenotype of the TfR-1 DN animal. The potential pay-offs of this high-risk, high gain proposal are models that define whether and, specifically, how iron is necessary for normal HC development at the molecular, protein and systems level. The models will be used to determine whether the lack of iron, per se, is responsible for the cognitive deficits in humans and animal models with dietary ID without the numerous confounding variables found in dietary models.

[unreadable] DESCRIPTION (provided by applicant): The primary goal of this grant proposal is to promote interdisciplinary research in neurobehavioral development at the postdoctoral level. We will target trainees who have received a Ph.D. in Child Psychology, Neuroscience or Developmental Neuroscience-related disciplines (e.g., molecular or developmental biology), as well as M.D.'s in various Pediatric disciplines, such as Neonatology, Pediatric Neurology and Child Psychiatry. The motivation behind this proposal is to foster the development of junior investigators who can integrate research and theory in human behavioral development with explication of underlying neural circuitry and neurodevelopmental processes. A long-range goal is to create a discipline we have come to call "neurobehavioral development." Clearly, knowledge of the neurobiological mechanisms underlying behavioral development would benefit those interested in a range of behavioral phenomena, and vice versa. To date there are relatively few developmental researchers who work at this interdisciplinary boundary in either basic or clinical domains. Consequently, there is a tremendous need to foster this integration among principal investigators and to support the interdisciplinary training of students. This is the mission of the Center for Neurobehavioral Development (CNBD) at the University of Minnesota, which will be home to this training grant. The CNBD accomplishes this mission by providing research space, educational colloquia and classes co-listed in multiple relevant departments, and by having a core faculty consisting of developmental, cognitive, behavioral, and basic neuroscientists working at multiple tiers of investigation in the human and in animal models. [unreadable] [unreadable]

0-6 weeks old; Ammon Horn; Behavioral; Brain; CRISP; Computer Retrieval of Information on Scientific Projects Database; Control Groups; Cornu Ammonis; Data; Diabetes Mellitus; Encephalon; Encephalons; Event-Related Potentials; Fe element; Funding; Grant; Hippocampus; Hippocampus (Brain); Infant; Infant, Newborn; Institution; Investigators; Iron; Link; Memory; Mothers; NIH; National Institutes of Health; National Institutes of Health (U.S.); Nervous System, Brain; Newborn Infant; Newborns; Research; Research Personnel; Research Resources; Researchers; Resources; Source; United States National Institutes of Health; design; designing; diabetes; event related potential; hippocampal; infant of diabetic mother; newborn human (0-6 weeks)

DESCRIPTION (provided by applicant): Normal brain development requires appropriate levels of nutrients, hormones, and other signaling molecules presented to the brain at precise developmental timepoints. For example, iodine deficiency results in reduced thyroid hormone (TH) production and severe developmental abnormalities. Similarly, copper (Cu) and iron (Fe) deficiencies during late brain development result in strikingly similar derangements in brain development. The long-term goal of the proposed research program is to understand the molecular basis of Cu, Fe, and TH action in the developing brain. To this end, the investigators have developed a model that seeks to identify a shared molecular mechanism causative of the aberrancies in brain development associated with these three deficiencies. Recent data have revealed that TH synthesis is reliant on adequate Fe levels. Fe is likely required for normal function of the TH synthesizing enzyme thyroid peroxidase. Interestingly, Cu deficiency is also associated with reduced TH levels. The investigators'preliminary data may provide an explanation for this latter finding. They have observed that Cu deficient rodents become Fe deficient. The Fe deficiency in these animals likely results in TH deficiency. Thus, they have formulated the following hypothesis: that Cu and Fe deficiencies lead to reductions in brain TH levels. The associated reduction in TH levels deleteriously affects brain development and therefore, contributes to the derangements in brain development and function observed in Cu and Fe deficient animals. Three specific aims are proposed to test these hypotheses: Aim 1 is to assess the effects of Cu and Fe deficiency during late brain development on circulating and brain TH levels. Aim 2 is to compare the molecular abnormalities associated with Cu, Fe, and TH deficiencies during late brain development. Aim 3 is to assess the effects of TH repletion on molecular abnormalities associated with Cu and Fe deficiencies during late brain development. These data will reveal whether reduced TH levels mediate some of the pathophysiological effects of Cu and Fe deficiency during neonatal brain development. These studies will further provide the preliminary data necessary to conduct mechanistic studies designed to reveal the precise contributions of each constituent towards brain development and function. If the hypotheses prove correct in model animal studies, it will be important to assess the TH status of Cu and Fe deficient infants to ensure that adequate TH status is obtained during neonatal development. Such findings may have a direct and immediate clinical impact, as even transient TH deprivation during late brain development is associated with reduced cognitive abilities later in life.

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Prime grant title: Behavior in Early Iron Deficiency, Prime PI: Betsy Lozoff, MD Center for Human Growth and Development, University of Michigan, Ann Arbor, MI Gestational and early postnatal iron deficiency occurs commonly in humans and results in altered behaviors suggestive of striatal dysfunction. Conversely, iron overload has been proposed to play a significant role in neurodegeneration. The purpose of this project is to investigate the effect of the iron deficiency and iron treatment on the developing brain using an animal model. Early iron deficiency alters the neurochemical profile of the developing striatum and accounts for abnormalities in striatum-dependent behavior in rats. Brain metabolite are non-invasively quantified from striatum of iron-deficient and iron-sufficient rat pups and the effects of different doses of iron supplementation will be determined using 1H NMR spectroscopy at 9.4T.

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The overall goal of this proposed project is to develop a comprehensive nutritional battery for the IA population and to assess the role of changes in nutritional status on neurobehavioral development.

PROJECT SUMMARY Anemia is a common medical condition in preterm infants. Previous studies generated from this Program Project Grant (PPG) showed that the degree of anemia contributes significantly to the neurodevelopmental outcomes of these individuals- particularly with respect to deficits in learning and memory. Anemia and its therapies (red blood cell transfusion and Erythropoietin (Epo) administration) expose the rapidly developing brains of premature neonates to potential neuropathologies. More severe anemia secondary to restrictive transfusion protocols risks brain hypoxia and iron deficiency (ID). Conversely, liberal transfusion protocols place the brain at risk for toxicity from iron overload and suppression of endogenous Epo- a potential neuronal growth factor. Treatment with exogenous Epo may be neuroprotective, but may also shunt limited neonatal iron reserves into red blood cells, thereby restricting iron delivery to the brain and causing more severe brain ID. The hippocampus, a major brain region underlying recognition learning and memory, differentiates rapidly in the neonatal period. Proper structural differentiation requires adequate oxygen, iron and growth factors. Neonatal ID anemia has particularly profound effects on the developing hippocampus, affecting its genome, metabolome, structure, intracellular signaling pathways, electrophysiology and specific behavioral functions. These deficits manifest during the period of ID and remain into early adulthood in spite of iron repletion. Our outcome studies of premature infants with neonatal anemia have suggested that these infants have similar neurodevelopmental abnormalities. The goal of Project 4 is to provide experimental evidence in unique, developmentally synchronized mouse models to establish mechanisms that underlie brain injury due to neonatal anemia and its treatments. The overall research aim of Project 4 is to evaluate the effects of phlebotomy-induced anemia and Epo treatment with or without supplemental iron between postnatal days (P) P3 and 12 on learning and memory. We will do this by assessing the behavioral function, metabolome, structure and neuronal mammalian target of rapamycin (mTOR) signaling status of the mouse hippocampus during the period of anemia and again in young adulthood. mTOR is a highly conserved signaling cascade that senses changes in neuronal nutritional, oxygen and growth factor status and responds by adjusting protein translation and actin polymerization rates, which in turn determine neuronal structure and function. In Aim 1, we will use unique models generated by our laboratory to test whether phlebotomy-induced anemia and Epo treatment with low or high dose supplemental Fe impair recognition learning and memory behavior. In Aim 2, we will test whether these same experimental conditions alter the neurometabolome and structure of the hippocampus. In Aim 3 we will test hypotheses about how oxygen, iron and Epo regulate kinases and genes in the mTOR pathway since the fundamental mechanisms by which neurons are dependent on oxygen, iron and Epo for growth and development are not understood.

? DESCRIPTION (provided by applicant): Published data indicate that 2-5% of the U.S. population has Fetal Alcohol Spectrum Disorder (FASD) - a set of physical anomalies and neurodevelopmental deficits caused by prenatal alcohol exposure (May & Gossage, 2001). Despite the profound public health burden, there have been no clinical trials that have attempted to directly address the neurodevelopmental deficits that are so debilitating in FASD. Extensive pre- clinical work (Thomas et al. and others) has provided evidence that choline supplementation is effective in attenuating the neurodevelopmental deficits caused by prenatal alcohol exposure in animal models. Our group has taken the initial steps toward translating this work to humans with two randomized, double-blind, placebo- controlled trials. We first conducted a pilot study to ensure the feasibility, tolerability, and safety of choline supplementation in 20 children with FASD (Fuglestad et al, 2013). Next, we completed a study of 40 additional participants with the goals of establishing a target dosage for young children, testing efficacy in the domain of memory, and determining a developmental window for choline's effects (detailed in `preliminary studies'). Briefly, our pilot data revealed that: 1. Children wih FASD consume insufficient dietary choline on average; 2. Choline supplementation was safe, tolerable and feasible for 2-5 year olds; 3. Supplementation for 9 months increased children's explicit memory performance relative to placebo; 4. Significant memory improvement was seen in 2-3 year olds but not 4-5 year olds. For 2-3 year olds, memory improvement was 21 percentage points in the choline arm compared to 2 percentage points in the placebo arm; 5. A dose ranging from 10-19 mg/kg was associated with the largest improvement in memory; 6. A very common single- nucleotide polymorphism (SNP) (rs12325817), related to endogenous choline production, appears to moderate the efficacy of choline for children with FASD. These findings directly inform the next study. Aim 1 involves evaluating a 19 mg/kg dose in 60 children with FASD, ages 2 to 5. This dosing scheme will optimize the neurocognitive benefits and further enhance tolerability of the intervention. In addition to continuing the evaluation of memory benefits from choline, Aim 2 adds measures of attention and executive function as possible additional targets. The NIH Toolbox Flanker Inhibitory Control and Attention Test and the Executive Function Scale for Early Childhood (pilot-tested during our last study) have been added. Aim 3 adds a longitudinal component - it will evaluate 40 children in the period two years after treatment to determine the permanency of choline's effects. Lastly, Aim 4 will further examine the role of known SNPs in choline synthesis as moderators to the observed treatment effects. In summary, the proposed study will continue the translation of choline's application - from experimental pre-clinical work to an evidence-based intervention for neurodevelopmental deficits in children with FASD.

PROJECT SUMMARY/ABSTRACT Long-term cognitive and behavioral deficits are the sequelae of iron deficiency (ID) prior to 3 years of age in children. A causal relationship between early-life ID and brain dysfunction has been established in rodent models, but not as clearly in humans due to a lack of peripheral biomarkers of brain iron status and function. Using a nonhuman primate model that closely mimics human iron biology, brain development and metabolism, we propose to discover novel biomarkers that index brain dysfunction in the pre-anemic stage of ID and evaluate the efficacy of early iron treatment for mitigating ID-induced brain dysfunction. We will serially measure from birth until 12 months, conventional hematological and iron-related indices, and novel proteomic- and metabolomic-based biomarkers in the blood (serum) and intrathecal (CSF) compartments of ID infants and iron sufficient control infants, concluding with neuroanatomical (MRI) and functional (behavior) assessments. Aim 1 will determine how best to employ serum proteomics and metabolomics to detect impending ID- induced brain dysfunction by delineating which analytes and when in the course of ID, the serum proteome and metabolome accurately reflect the brain metabolic, structural and functional impairments. We predict that specific protein and metabolite changes reflecting distinct iron-regulated pathways will be detected in the serum in the pre-anemic period and provide biomarkers of impending brain dysfunction. Aim 2 will quantify and model the sensitivity of conventional hematological and serum iron parameters for detecting brain dysfunction by serially monitoring these parameters relative to the metabolomic and proteomic indices of brain dysfunction in concurrently obtained CSF. We predict that brain ID and dysfunction will be evident prior to the appearance of anemia, indicating that hematological parameters used in clinical practice are insensitive as biomarkers of brain iron and metabolic status. Aim 3 will test the hypothesis that iron treatment prior to anemia is essential to mitigate the adverse neurological effects of ID. ID infants will be randomized to iron treatment either in the pre-anemic stage of ID or after the development of anemia. The efficacy of the two therapies for restoring hematological indices and brain iron status, metabolism, structure and function will be determined. We predict that both treatments will normalize hematological indices, but only iron treatment begun in the pre-anemic stage will fully restore brain iron status, metabolism, structure and function. This project is significant, because it focuses on the benefits of early screening and interventions for improving the neurodevelopment of children at risk for early-life ID. It is innovative because it will employ novel proteomic and metabolomic analyses to simultaneously probe the blood and intrathecal compartments in a primate model that uniquely mimics the iron and metabolic demands of the human infant. The discovery of functional biomarkers will achieve our ultimate translational goal of optimizing screening and treatment strategies in children at risk for early-life brain ID.

ABSTRACT Anemia is a common medical condition in preterm infants. Previous studies show that neurodevelopmental outcomes of preterm infants are dependent in part on the degree of anemia. In a developmentally appropriately-timed neonatal mouse model, phlebotomy induced anemia (PIA) of the degree commonly seen in hospitalized preterm infants results in significant short-term dysfunction and long-term injury to multiple brain areas including the hippocampus, prefrontal cortex, striatum and cerebellum. Potential therapies for PIA include erythropoietin (rHuEPO) administration and red blood cell transfusion (RBCTX). Each therapy has the potential advantage to relieve tissue hypoxia induced by anemia, but also expose the rapidly developing premature neonatal brain to potential neuropathologic processes. Treatment with rHuEPO may be neuroprotective or alternatively, shunt limited neonatal iron reserves into RBCs and thus restrict iron delivery, leading to worsening brain iron deficiency (ID). Animal models of neonatal anemia due to ID demonstrate particularly profound effects on the developing brain, including its genome, metabolome, structure, intracellular signaling pathways, electrophysiology and behavioral output. RBCTX, while alleviating tissue hypoxia due to anemia, places the brain at risk for iron overload, inflammation and suppression of endogenous EPO production ? a potential neuronal growth factor. The overall research aim of this proposal is to evaluate whether rHuEPO treatment or RBCTX to relieve PIA in the newborn mouse pup between postnatal days (P) P3 and P14 improves regional brain development and function in the neonatal period and in young adulthood following resolution of anemia. This will be done by assessing the behavioral function, neurometabolome, and gene and protein expression in 4 brain regions in the neonatal and adult mouse that we have demonstrated in the previous 5 years are compromised by PIA. Aim 1 tests whether treatment of PIA with rHuEPO beginning either prior to the onset of anemia or once anemia is present rescues the developing brain from the adverse effects of untreated PIA. Aim 2 tests whether treatment of PIA with RBCTX initiated at the two hematocrit thresholds utilized in human trials results improves neurodevelopmental outcome in the mouse. A multi-tiered developmental neuroscience approach that spans gene expression to behavior is necessary provide the needed mechanistic understanding for the anticipated results of ongoing clinical studies by the Neonatal Research Network of the National Institutes of Child Health and Development and to model effects of PIA and its treatments on neurodevelopment.

Abstract Exciting pre-clinical research supports a role for gut microbes (microbiomes) in modulating brain function and behavior. An important observation stemming from studies in animals is that developing brains are more susceptible to the effects of microbiome modulation than mature brains, supporting the idea that there is an early-life sensitive period for brain developmental programming by the microbiome. The hippocampus, a brain region responsible for learning and memory, is a target of microbiome-mediated effects in adult mice; however a relationship between early-life microbiomes and programming of hippocampal function in humans has not been studied. In preliminary experiments, we have found that an infant cohort predicted to have disrupted gut microbiomes (due to antibiotic exposure) exhibited abnormal recognition memory responses (indexed by event-related potentials (ERPs)) at 1 month of age, as compared to unexposed infants. Given these findings, we hypothesize that variations in microbiome signatures during infancy correlate with differences in hippocampus function, and that early-life events that disrupt the microbiome will result in a developmental delay in acquisition of learning and memory functions in affected infants. In the proposed studies, we capitalize on our group?s unique abilities to quantify hippocampal function in very young infants and to compare these functions to microbiome features using state-of-the-art computational strategies to discover microbiome determinants of hippocampus function. In Aim 1, we will use natural variation in microbiome composition in a healthy infant cohort that is relatively free of confounding variables to define microbiome groups. In Aim 2, we will compare two groups of otherwise healthy infants that differ with respect to microbiome disruption (antibiotic exposure) as newborns. For both Aims, we will characterize and compare human hippocampus function during its most rapid phase of development, in very young infant microbiome cohorts, using cutting-edge infant neurobehavioral testing approaches that our team at the U of MN Center for Neurobehavioral Development is uniquely qualified to execute. Infants will be compared using established auditory (1 mo of age) and visual (6 mos of age) recognition ERP paradigms to determine if microbial variation modulates hippocampus function and, further, to identify specific healthy microbiome features (biodiversity, abundances of key taxa) that define optimum hippocampus function. The potential high-impact gain of this R21 research is that it will provide evidence that gut microbes affect the brain at very early times in postnatal human neurodevelopment with a likelihood, then, of shaping long-term brain health. In contrast to genetic factors, gut microbes can be modified. Thus, our results will lay the foundation for future studies to develop microbiomes for early interventions and for protection of healthy microbiomes via improved antibiotic stewardship, during the developmental window of high brain plasticity, to improve brain development in at-risk individuals.

Project Summary/Abstract Neurodevelopmental processes are shaped by dynamic interactions between genes and environments. Maladaptive experiences early in life can alter developmental trajectories, leading to harmful and enduring developmental sequelae. Pre- and postnatal hazards include maternal substance exposure, toxicant exposures in pregnancy and early life, maternal health conditions, parental psychopathology, maltreatment, structural racism, and excessive stress. To elucidate how various environmental hazards impact child development, it is imperative that a normative template of developmental trajectories over the first 10 years of life be established based on a sufficiently large and demographically diverse sample of the US population. To accomplish this, the Healthy Brain and Child Development National Consortium (HBCD-NC) has been formed to deploy a harmonized, optimized, and innovative set of neuroimaging (MRI, EEG) measures complemented by an extensive battery of behavioral, physiological, and psychological tools, and biospecimens to understand neurodevelopmental trajectories in a sample of 7,500 mothers and infants enrolled at 24 sites across the United States (US). The HBCD-NC will carry out a common research protocol under direction of the HBCD- NC Administrative Core (HCAC) and will assemble and distribute a comprehensive and well-curated research dataset to the scientific community at large under the direction of the HBCD-NC Data Coordinating Center (HDCC). The overarching goal of the HBCD-NC is to create a comprehensive, harmonized, and high- dimensional dataset that will characterize typical neurodevelopmental trajectories in US children and that will assess how biological and environmental exposures affect those trajectories. A special emphasis will be placed on understanding the impact of pre- and postnatal exposure to opioids, marijuana, alcohol, tobacco and/or other substances. To address these broad objectives, the sample of women enrolled will include: 1) a racially, ethnically, and socioeconomically diverse cohort that is representative of the US population; 2) pregnant woman with use of targeted substances (opioids, marijuana, alcohol, tobacco); and 3) demographically and behaviorally similar women without substance use in pregnancy to enable valid causal inferences. In addition, the HBCD-NC will identify key developmental windows during which both harmful and protective environments have the most influence on later neurodevelopmental outcomes. The large, multi- modal, longitudinal, and generalizable dataset that will be produced for the first time by this study will provide novel insights into child development using state-of-the-art methods. The HBCD-NC study will inform public policy to improve the health and development of children across the nation.