Quantifying Breast Milk Retinol Inadequacy and the Impact on Neonatal Outcomes in a Midwestern United States Population of Postpartum Women

Background: Low serum antioxidant concentrations at birth can lead to oxidative stress, bronchopulmonary dysplasia, retinopathy, and necrotizing colitis in infants. Specifically, low retinol (Vitamin A1) levels can cause night blindness and impaired immune system function. Retinol inadequacy is a well-documented nutritional issue in developing countries. According to World Health Organization survey data, low Vitamin A serum levels (less than 300 mcg/L) impact approximately one third of pre-school aged children and more than 15% of pregnant woman in at-risk populations. However, there is a lack of understanding about the prevalence of breast milk retinol inadequacy in developed countries. For vitamin A deficiency to constitute a moderate public health problem by WHO biochemical standards, population retinol must reach between 10-25% for breast milk inadequacy or 10-20% for maternal serum deficiency. Objective: The purpose of this study is to quantify the prevalence of breast milk retinol adequacy (greater than 300 mcg/L), insufficiency (between 200 – 300 mcg/L) and deficiency (less than 200 mcg/L) in a Midwestern United States population of postpartum women. A secondary aim is to identify the relationship amongst breast milk retinol concentrations and birth outcomes. Experimental Design: An IRB approved study enrolled 24 infant-mother pairs. Data analysis was performed on subjects with breast milk nutrient analyses available. Descriptive statistics were run for all variables, including maternal retinol activity equivalents. Spearman correlation coefficients were used to assess the relationship between maternal blood retinol and breast milk retinol, cord blood retinol and breast milk retinol, and breast milk retinol and birth outcomes. Median corrected gestational age statistics and breast milk retinol levels were compared amongst maternal serum retinol groups. Results: In our population of postpartum mothers, only 56% of participants had breast milk retinol adequacy, with 36.4% of participants achieving maternal serum retinol adequacy. Retinol category results are summed up in Table 1. Median maternal retinol activity equivalents was 1740 mcg/L (range=651mcg/L - 3436mcg/L). There was no significant correlation between maternal serum retinol level and breast milk retinol levels (R=0.24, p=0.915). Additionally, there was no significant correlation between maternal retinol activity equivalents and maternal serum retinol level (R=.008, p=0.973) or breast milk retinol level (R=-.192, p=0.381). There was a significant negative correlation between breast milk retinol level and the number of oxygen therapy days during infant admission (R=-0.483, p=0.017). Conclusion: Based on these results, breast milk and maternal serum retinol inadequacies may constitute a serious and moderate public health problem, respectively, for postpartum mothers in the Midwestern United States. These results suggest that breast milk retinol adequacy promotes healthy lung development in neonates. Further, breast milk retinol levels may be independent of maternal serum retinol levels and maternal retinol activity equivalents. Limitations of this study include a small sample size of mothers whose preterm skewed infants were all admitted to the NICU. Future studies should focus on replicating these results with a larger heterogenous sample size.https://digitalcommons.unmc.edu/surp2020/1020/thumbnail.jp

Comparing Intrauterine Transfer Rates and Maternal Plasma Levels of Carotenoids In Maternal-Infant Pairs Between Gestational Age Groups

Background: Carotenoids are recognized as potential antioxidants with a wide range of functions in humans, such as protecting eye health. Carotenoid levels in infant cord blood are generally lower than in maternal serum. Still, little research has assessed on the intrauterine transfer rate of carotenoids between mothers and infants at varying gestational ages. Objective: This study aimed to identify differences in intrauterine transfer rates of carotenoids between five gestational age groups. Experimental Design: An IRB-approved study enrolled 308 maternal-infant pairs at delivery. Gestational age was categorized into five groups: extremely preterm (\u3c28 weeks), very preterm (28 to \u3c32 weeks), moderately to late preterm (32 to \u3c37 weeks), early term (37 to \u3c39 weeks), and term (\u3e39 weeks). Maternal blood and umbilical cord samples were collected at birth and analyzed for carotenoid nutrient levels using high-performance liquid chromatography. Demographic and clinical outcome data were collected from the electronic health record. Intrauterine transfer rates were calculated as [(umbilical cord blood nutrient level/maternal serum level)*100]. Descriptive statistics were generated. The Kruskal-Wallis test was used to compare the intrauterine transfer rates of carotenoids between the gestational age groups. Post-hoc pairwise comparisons were used to assess specific inter-group differences. A p-value of \u3c0.05 was considered significant. Results: Median birth gestational age was 39 2/7 weeks with 3 (1%) infants in the extremely preterm group, 9 (2.9%) in very preterm, 33 (10.7%) in moderately to late preterm, 70 (22.7%) in early term, and 193 (62.7%) born term. There was a significant difference in intrauterine transfer rate between gestational age groups for lutein + zeaxanthin (L+Z), a-carotene, and total B-carotene (Table 1). Post-hoc pairwise comparisons showed significant differences between term and moderately preterm for L+Z (p=0.016), term and extremely preterm for L+Z (p=0.041), and term and moderately preterm for a-carotene (p=0.003). Table 1. Comparison of Median Intrauterine Transfer Rates in Maternal-Infant Pairs Between Gestational Age Groups Transfer Rate p-value between all groups lutein + zeaxanthin 15.6% 0.001 total lycopene 4.4% 0.070 β-cryptoxanthin 11.0% 0.112 ⍺-carotene 8.6% 0.03 β-carotene 6.1% 0.037 Conclusion: There may be a relationship between intrauterine transfer rates of carotenoids and gestational age groups. Further research is needed to fully understand the clinical significance of this observed relationship and ascertain what interventions, if any, are ideal for maternal-fetal health. This study is limited by the low number of participants in the extremely preterm and very preterm groups.https://digitalcommons.unmc.edu/surp2020/1007/thumbnail.jp

Using Zika Virus Plasmid to Increase Amyloid Precursor Protein in Alzheimer’s Disease Protein and Discovery of Novel IRF9 Protein

Two projects are featured in this thesis, one focusing on increasing levels of amyloid precursor protein (APP) in Alzheimer’s disease (AD) proteins and the other outlining the discovery of a novel IRF9 protein. AD is a debilitating neurodegenerative disease characteristically featuring the development of amyloid-beta plaques and neurofibrillary tangles. The P2 plasmid from the Zika virus was converted into cDNA and injected into mouse models. Western blotting analysis was used to detect and analyze the presence and amplification of APP and tubulin. The addition of the P2 plasmid enhanced the levels of APP within the cell. This data will be helpful in further investigation into the mechanisms of AD and in designing a potential treatment for the disease. Interferon regulatory factors (IRFs) are transcription factors that activate Type I interferons. IRF9 is an important regulatory factor within the JAK-STAT signaling pathway, associated with cell immunity and other homeostatic processes. The Epstein-Barr virus has been known to persist in latency in B lymphocytes and regulate complex cellular regulatory networks. A novel protein, primate-specific (PS)-IRF9, was identified by the Zhang lab, and this experiment was done to confirm its presence. Cell lysates from Akata, IB4, and Jijoye EBV latency cell lines were used, and western blotting analysis was performed to analyze the presence of IRF9 variations. Akata is a Type I latency cell, whereas IB4 and Jijoye are Type II latency cells. The presence of PS-IRF9 was confirmed in the Akata cell lineage but absent in the IB4 and Jijoye cell lineage, showing a potential link between cell latency and different IRF9 proteins