Figure 5.

The role of autophagy on biliary epithelium differentiation and homeostasis. Autophagy is involved in the maintenance and functions of progenitory cells in the liver (HPC). It negatively correlates with biliary tree formation, it decreases in the early stages of HPC development while it increases in the late stages. HPC differentiation to cholangiocyte is controlled by the Notch signaling pathway. In cholangiocytes, the under nutrient-rich condition or absence of rapamycin, mTOR blocks autophagy resulting in an increased Notch-STAT3 cascade signaling pathway and promoting cellular differentiation. On the contrary, autophagy induction via rapamycin (an mTOR inhibitor) or nutrient deprivation attenuates the Notch signaling pathway resulting in a reduced biliary differentiation.