732 - Gut-Brain Metabolomic Pathways in Infants with Neonatal Opioid Withdrawal Syndrome

Publication Number: 732.5395

Leida Voulgaropoulos, Georgetown University School of Medicine, Washington, DC, United States; Keisha Wolfe, Children's National Health System, Leesburg, VA, United States; Suhasini Kaushal, MedStar Georgetown University Hospital, Washington DC, DC, United States; Lewis P. Rubin, Georgetown University School of Medicine, Washington, DC, United States

Background: Neonatal opioid withdrawal syndrome (NOWS) continues to present a major public health challenge. Prenatal opioid exposure can decrease motility and may affect the intestinal microbiota, inducing dysbiosis and altering microbial-dependent metabolites. To our knowledge, no previous studies have interrogated intestinal metabolomic pathways in NOWS.

Objective: To determine if neonates with NOWS exhibit altered fecal metabolite pathways and microbial dysbiosis.

Design/Methods: A prospective cohort study enrolled term neonates with NOWS (n=13) and age-matched controls (n=9). NOWS was diagnosed by a positive opioids screen (mother &/or neonate) with clinical signs. Stool samples were obtained between day of life 3 and 7. Fecal non-targeted small molecule profiling was performed using UHPLC-MS:MS. Following normalization to mass extracted and log transformation, 2-sample t-tests and principal component analysis (PCA) were used to identify compounds differing significantly between groups. Metabolite distributions were compared using partial least squares-discriminant analysis and hierarchical clustering. Variable region 16S rRNA gene sequencing was used to profile fecal microbiomes.

Results: A total of 1083 distinct identifiable compounds were detected in the fecal samples; 326 significantly differed between groups (p < 0.05). Pathway analysis revealed significant alterations in the NOWS group including excitatory amino acids, neurotransmitters, microbially-produced metabolites, bile acids, and inflammatory and oxidative stress mediators. Since most NOWS neonates were formula-fed and most controls were breastfed, we adjusted PCA interpretation for known fecal metabolite differences between formula- and breastfed newborns. Microbial profiling also revealed group differences in intestinal microbiome.

Conclusion(s): Our study demonstrates changes in fecal neuroactive, stress, and inflammatory pathways associated with NOWS. Limiting factors for interpretation include small sample size and dietary differences between groups. Nevertheless, after compensation for dietary differences, our findings support an altered gut-microbiome-brain axis in NOWS. Activation of specific neuroactive and inflammatory pathways may underlie some of the pain sensitized and behavioral phenotype in NOWS and previously described changes in intestinal T cell polarization. Further investigations using this strategy may point to microbiome and metabolic pathway interventions to ameliorate visceral pain and other neurobehavioral effects in NOWS.