Figure 10.

Working model of the coordinated regulation of bile acid and cholesterol elimination in cholesterol-fed mice. Dark green arrows relate to bile acid (BA) transport, yellow arrows to cholesterol (CS) transport, and gray arrows to phospholipid (PL) transport. Upregulated genes are depicted in red, unaltered genes are depicted in white, and downregulated genes in light green. ❶ Dietary CS from CS-rich diet is absorbed in the intestine. ❷ CS uptake is increased in the liver. ❸ Hydrophilic BA synthesis from CS and conjugation is augmented. ❹ Neo-synthetized BAs are secreted in bile ducts along with CS and PL. ❺ Expression of jejunal CS transporters and ileal BA recycling is diminished, resulting in enhanced elimination of neo-synthesized BAs and CS in feces. ❻ Reduction in portal reclamation of BAs results in ❼ elevation of blood BA levels. ❽ Reduced renal BA reclamation leads to increased urinary excretion.