In vitro effects of the chemotherapeutic compound 5-Fluorouracil (5-FU) on gut microbiota composition and SCFA concentrations

Fecal samples were collected from ten postmenopausal women (56-72 years) and processed under anaerobic conditions. Subsequently, samples were pooled and inoculated in the TNO in-vitro model of the colon (TIM-2). This computer-controlled model maintained a physiological pH and temperature, simulated peristaltic waves, and absorbed microbial metabolites, thereby closely mimicking the gut environment. Samples were treated with 26.4mg 5-FU in the morning and 26.4mg 5-FU in the afternoon for three consecutive days. Samples from the lumen (reflecting the colonic microenvironment) as well as the dialysate (reflecting the metabolites absorbed into the circulation) were analyzed at T0 (before start of the intervention), T24, T48 and T72.