Enterotoxigenic <i>Escherichia coli</i> (ETEC) is a leading cause of childhood death from diarrhea and the leading cause of Traveler's diarrhea.<i>E. coli</i> heat-stable enterotoxin (ST) is a major virulence factor of ETEC and inhibits the brush border Na/H exchanger NHE3 in producing diarrhea.
Reduced NHE3 expression or function has been implicated in the pathogenesis of diarrhea associated with inflammatory bowel disease (IBD) or enteric infections.
Na<sup>+</sup>/H<sup>+</sup> exchanger-3 (NHE3) is crucial for intestinal Na<sup>+</sup> absorption, and its reduction has been implicated in infectious and inflammatory bowel diseases (IBD)-associated diarrhea.
Studies have shown that a decrease in both NHE3 (Na<sup>+</sup>/H<sup>+</sup> exchanger) and DRA (downregulated in adenoma, Cl<sup>-</sup>/[Formula: see text] exchanger), resulting in decreased electrolyte absorption, is implicated in infectious and inflammatory diarrhea.
Furthermore, they support the notion that mislocalization of transporters, such as NHE3 substantially contributes to the reported sodium loss diarrhea.
It was shown that the expression levels of NHE3 and AQP4 were significantly increased in the diarrhoea mice treated with berberine compared with the untreated diarrhoea mice.