Correlations among the Toddler Gut Microbiome and Health Status Variables
Poster May 08, 2018
Samia Dutra, Maureen Groer, PhD, Ming Ji, PhD, Allyson Duffy, PhD, Kathleen Armstrong, PhD, Larry Dishaw, PhD, Elizabeth Miller, PhD, Alyson Yee, Jack Gilbert, PhD.
Objective: This study explored correlations among the toddler gut microbiome of formerly very low birth weight infants and health status variables. Method: Approval for this study was obtained from the university Institutional Review Board and informed consent was obtained from the mothers. We followed VLBW infants (<1500 Gms) during 6 weeks of the NICU stay and followed up with home visits and stool collection at 2-3 years of age on 18 toddlers. We analyzed relationships between the toddler gut microbiome and health variables (hemoglobin, frequency of illness during the first year of life, and introduction of solid foods) collected when they reached 2-3 years of age.Eighteen stool samples from these children when they reached 2-3 years of age (mean age =X months old) have been sequenced.. Stool swab samples were stored at -80oC prior to use. Microbial genomic DNA was extracted using the PowerSoil-htp 96 Well Soil DNA Isolation Kit (MoBio). DNA Samples were forwarded to the lab of Dr. Jack Gilbert (Argonne National laboratory and University of Chicago). The microbial content was profiled with 16SrRNA sequencing. PCR of the 16S rRNA V4 region (515F-806R) was performed and sequenced using the Illumina MiSeq platform to generate ~100,000 250 bp paired end reads per sample.Results: The study enrolled 18 toddlers who were VLBW infants with a mean gestational age of 28.3 weeks (range 25.3 to 32.4), and a mean birth weight of 1115.06 gms (range 675-1485 gms). The gender distribution was equal. Length of NICU stay mean was 68.67 days, with a range of 22 to 123 days. At the toddler home visit, the OTU abundance of the x stool samples showed i a higher abundance of Firmicutes to Bacteroidetes . Hemoglobin level was inversely related to Actinobacteria abundance in toddlers (r=-.697, p=.001, R2=0.486). The remaining OTU abundances showed weak or non-significant correlations to Hgb. However, Firmicutes and Bacteroidetes showed a significant variability prediction. Hemoglobin level was related to Bacteroidetes abundance in toddlers (r=.479, p=.044, R2=0.229) and inversely related to Firmicutes abundance in toddlers (r=-.516, p=.028, R2=0.266).Frequency of illness during the first year of life, age and introduction of solid foods were related to Actinobacteria abundance. Actinobacteria phylum abundance was positively related to the frequency of fever in the first year of life,
(r=.609, p=.007). We used multiple regression to assess the unique roles played by frequency of fever in the first year of life, age, and hemoglobin level on actinobacteria abundance. Frequency of fever in the first year of life and hemoglobin level showed moderate semi-partial correlations with the outcome: the frequency of fever in the first year of life semi-partial correlation was .426 and the hemoglobin level semi-partial correlation was -.547. The age of the child showed weak semi-partial correlation of -.059. Later introduction of solid foods was related to Tenericures (r=.804, p=.000). Conclusions: Firmicutes, Bacteroidetes, and Actinobacteria constitute the most abundant phyla in the human intestinal microbiota, with Firmicutes and Bacteroidetes being predominant in healthy adults and Actinobacteria in breast-fed infants. . The correlation between hemoglobin level and the gut microbiome suggests that certain species of gut bacteria could influence hematopoiesis and how the body processes oxygen. It is also possible that diet plays a role in this relationship. The gut microbiome is an important regulator of physiological and pathophysiological effects. Further research is necessary regarding children’s health and hemoglobin relationships with gut microbiome.