BAs in circulation are highly upregulated in a mouse model of chemotherapy. (A) The experimental setup of 5-FU treatment of mice. (B-D) 5-FU treatment and recovery in mice. PB total myeloid cellularity (B), BM total cellularity (C), and the number of lineage⁻ cells (D) are shown (n = 3 for each time point). (E) TBA measurement in different phases of treatment and recovery in 5-FU–treated mice. (D) Different phases of treatment and recovery were based on lineage⁻ cells (n = 5-14). (F) Production of primary BAs through the classic (black) and alternative (red) pathways. (G) Relative expression levels of key BA-producing enzymes in liver at different time points in 5-FU–treated mice. Fold change relative to control samples is shown (n = 5). (H) Expression changes in the main reuptake and efflux pumps in liver at recovery from 5-FU treatment, compared with the control. Fold change relative to control samples is shown (n = 5). Results are presented as means ± SEM. *P < .05; **P < .01; ***P < .001.