Cell Host Microbe 22, 757–765 (2017)

It is known that antibiotics not only target bacteria but also can alter host metabolism by damaging mitochondrial function. In Cell Host & Microbe, Collins and co-workers investigate the effects of antibiotics on host metabolism and their influence on antibacterial responses. Using a mouse model of infection with Escherichia coli, they find that the production of gut epithelial metabolites is altered by treatment with antibiotics in a microbiota-independent manner. These antibiotics-triggered epithelial metabolites diminish the efficacy of antibiotics directed against pathogenic bacteria but can improve the phagocytic function of macrophages. In contrast, the application of antibiotics directly to macrophages impairs their phagocytic and killing function, probably through alterations in the mitochondria-dependent respiratory burst. Treatment with antibiotics therefore exerts complex direct and indirect effects on host-cell metabolism, with effects on antimicrobial function.