Fellow Georgetown University School of Medicine Washington, District of Columbia, United States
Background: Opioid use in pregnancy has increased in recent decades with a synchronous rise in hospitalizations for neonatal opioid withdrawal syndrome (NOWS). Prenatal opioid exposure variously has been proposed to activate gut mu receptors, decrease motility, and affect intestinal microbiota (dysbiosis) and bacterial metabolites, which may underlie gut-brain dysfunction in NOWS. This is the first study to our knowledge to evaluate effects of prenatal opioid exposure on the neonatal microbiome and metabolomics. Objective: To determine if infants with NOWS exhibit intestinal dysbiosis and altered microbial metabolite profiles. Design/Methods: This prospective cohort study enrolls term neonates with NOWS and age-matched controls (9 subjects in each group to date). NOWS diagnosis requires a positive opioid toxicology screen (mother &/or neonate) and clinical signs. Stool samples are obtained between day of life 3 and 7. We perform fecal DNA microbiome profiling (amplicon-based 16S V3-V4 rRNA gene sequencing) and DNA metagenomic sequencing (to determine global metabolic, immunomodulatory, and neuroactive bacterial gene expression pathways). Fecal non-targeted small molecule profiling is performed using UHPLC-MS:MS (Metabolon) and automated comparison of ion features to a comprehensive library of chemical standards. We will calculate alpha and beta diversity and relative abundance at phylum, family, and genus levels. Metabolomic analyses will use Metabolon software for detection and quantification of metabolites and data comparisons (ANOVA, repeated measures analysis). Fecal bacterial DNA isolation and DNA library construction for samples are in progress. Targeted and metagenomic sequencing (Illumina MiSeq), untargeted metabolomics, and bioinformatics will be completed in early 2024, followed by transcriptome/metabolome comparative analysis. We expect to determine if (1) NOWS is associated with intestinal dysbiosis and (2) NOWS infants have an altered gut-brain axis typified by neuroactive intestinal (postbiotic) metabolite production.
