Fig. 3

The time-dependent alteration of BAs and microbe species in response to HFD. a Alteration of BAs shown by trajectories based on t values of principal component 1 (PC1) and PC2 of partial least squares discriminant analysis (PLS-DA). The red lines from D0 to D0.5 and D0.5 to D1 highlight when the most dramatic changes occurred. b Alteration of microbiota shown by trajectories based on t values of PC1 and PC2 of PLS-DA. The red lines from D1 to D2 and D2 to D3 highlight when the most dramatic changes occurred. c The concentration of each BA and the abundance of microbe species were compared between control (n = 5) and HFD (n = 5) groups at the corresponding time points. The BAs and microbes were recorded when they were significantly altered at the earliest time point. The number of recorded BAs and microbes is shown in the line charts, and the peaks of the two lines are highlighted in red. d The BAs and microbes selected in Fig. 4c are listed along the timeline, where red and green indicate high and low concentrations, respectively, in the HFD group relative to the control group at each corresponding time point