Dietary emulsifier consumption alters gene expression in the amygdala and paraventricular nucleus of the hypothalamus in mice

Purpose: The goal of the current study was to test whether emulsifier consumption is associated with changes in gene expression in the amygdala and PVN Methods: Adult male C57BL/6J mice received drinking water containing either 1% sodium carboxymethylcellulose (CMC), 1% polysorbate-80 (P80) or water without emulsifier for 12 weeks. PVN and amygdala gene expression was generated by RNA-Seq using an Illumina NextSeq 500. FastQ quality filter was used to filter low quality sequences and Tophat, Bowtie, Cufflinks, and Cuffdiff were used for RNA-Seq analysis. qRT–PCR validation was performed using 6 differential genes of interest. Results: A total of 243 genes were differentially expressed in the amygdala and PVN of emulsifier-treated mice compared to controls. There was minimal overlap of differentially expressed genes in CMC- and P80-treated animals, suggesting that each emulsifier acts via distinct molecular mechanisms to produce an anxiety-like phenotype. Furthermore, gene ontology and pathway analysis revealed that various stress, metabolic, and immune terms and pathways were altered in emulsifier conditions. RNA-seq data was validated with qRT–PCR data (R2= 0.8815). Conclusions: These findings are the first to demonstrate that emulsifier consumption changes gene expression in brain regions that are critical for stress responding, providing possible molecular mechanisms that may underly the observed anxiety-like phenotype Amygdala and PVN gene expression in adult male mice that consumed emulsifiers for 12 weeks