conducted a pilot screening using a broth micro-dilution assay they developed through a previous high-throughput screening method.
The team found that anthelmintics, such as niclosamide, oxyclozanide, rafoxanide, and closantel, inhibited the growth of the pathogen strain 60190.
The use of multiple antimicrobial agents can decrease bacterial resistance and re-establish the clinical efficacy of certain antibiotics. Describing how this can occur, the researchers mentioned how the compounds have an inhibitory role on adhesion, with niclosamide inhibiting the secretion of IL-8, despite acidic conditions where it remained stable.
The team used a number of methods in their analyses, including scanning electron microscopic observations, light microscopy, cytotoxicity testing and in vivo efficacy. Antibacterial susceptibility, kinetic, adhesion and invasion, motility and gene expression assays were also conducted, with researchers also investigating the emergence of resistance and membrane potentials.
Using a Two-way ANOVA, followed by a Bonfererroni post-test, the team carried out statistical analyses of their data.
The research team found that niclosamide administration decreased transmembrane pH, indicating that that anti-pathogen activity was related to the disruption of its proton motive force. Niclosamide was effective in infection models, and could be developed further to fight infection by the pathogen.
Results should be confirmed using more strains of the pathogen.