A Novel eADO Biosensor Microelectrode Array (MEA) for Real-Time Electrochemical Detection of eADO Release From Mouse or Human Gut

Abstract

Salmonella typhimurium (S. typhi) at 107 cfu for 3 days. RESULTS: Although ubiquitously expressed, immunofluorescence confirmed high expression of ZBP-89 protein with serotonin in both mouse and human gut EC cells. ZBP-89Δcolon mice exhibited a 50% reduction in the numbers of serotonin-positive EC cells in the colon, but not the small intestine. Serotonin tissue content in the colon determined by ELISA was also reduced. A microarray analysis of WT versus ZBP-89Δcolon mice revealed an ~4-fold decrease in TPH1 and chromograninA mRNA. Quantitative PCR was used to verify the decrease in ZBP-89 and TPH1 mRNA in 4 mice. Two ZBP-89 consensus elements were identified in the TPH1 promoter. EMSAs and DAPA confirmed ZBP-89 binding to both elements along with Sp1 and Sp3 transcription factors. Mutation of both GC-rich DNA elements in the TPH1-Luc reporter abolished promoter activity. Infecting the ZBP-89Δcolon mice with S. typhi resulted in less submucosal edema than in the ceca of infected WT mice. CONCLUSIONS: ZBP-89 is required for basal TPH1 expression and serotonin production. Reduced TPH1 expression in the ZBP-89Δcolon mice appeared to mitigate the acute mucosal effects of S. typhi infection, presumably due to less serotonin production and fluid secretion.