Figure 2.

Circulating levels of (A) betaine, (B) choline, and (C) trimethylamine N-oxide (TMAO) in human subjects (black bars) with normal renal function compared to patients with chronic kidney disease (CKD) stage 3 and 5, as well as different animal species, i.e. free-ranging, active brown bears; captive brown bears; captive, active garden dormice; wild boars; captive lions; and captive tigers. Animals are color-coded depending on their diet, i.e. omnivores (dark grey bars), and carnivores (light grey bars). Results are shown as median (interquartile range). Overall p values between the three groups of human subjects, as well as between animal species, were assessed by non-parametric Kruskal–Wallis test. Group-wise comparisons using Bonferroni post hoc analysis are described in the Results section. Number of participants or animals included in each group is depicted.