Inhibition of fibrosis Release of chemokines and cytokines by injured cholangiocytes and infiltrating inflammatory cells [255] as well as hepatic stellate cell proliferation induced by bile salts may play a role in fibrogenesis [256] . UDCA has been reported to delay development of severe fibrosis and cirrhosis in PBC [221] . This may be related to the aforementioned anticholestatic and anti-apoptotic effects rather than direct antifibrotic effects of UDCA. The bile salt derivatives 6-ethyl CDCA (6-ECDCA) and nor-UDCA inhibit fibrosis in the bile-duct-ligated mouse. While 6-ECDCA seems to mediate this antifibrotic effect via farnesoid X receptor (FXR) and small heterodimer partner (SHP) [257] , the mechanism of action of nor-UDCA remains yet unclear [258] .