The intestinal bile acid-activated nuclear receptor FXR (farnesoid X receptor, coded by the Nr1h4 gene) has emerged as a major player in metabolic regulation.30 FXR transcriptional activity was stimulated during the HF diet, as evidenced by a strong induction of its two major target genes Fgf15 (coding for the fibroblast growth factor 15) and Nrob2 (coding for the small heterodimer partner SHP) (Figure 5d). Here, NR1H4 is linked to hydrops fetalis.