Vitamin D modulates biliary fibrosis in ABCB4 deficient mice

Background: Vitamin D deficiency is a hallmark of many chronic liver diseases. Impaired vitamin D-VDR signalling might represent an aggravating factor during liver injury (Zuniga et al. 2011) and recent studies suggest that vitamin D exerts a protective role in biliary-type liver diseases (Chignard et al. 2012). To assess the effect of vitamin D on biliary fibrosis, we now treated ATP binding cassette transporter knockout (Abcb4-/-) mice as established model of chronic cholangitis and biliary fibrosis with 25-hydroxyvitamin D. Methods: Abcb4-/- (n=60) and wild-type mice (n=54) were fed a vitamin D-supplemented d…