Intracellular labile iron is a key regulator of hepcidin expression and iron metabolism

Liver iron overload can induce hepatic expression of hepcidin and regulates iron metabolism. However, the mechanism of iron regulating iron metabolism remains known. Intracellular labile iron represents the nonferritin-bound, redox-active iron which is transitory and serves as a crossroad of cell iron metabolism. The role of intracellular labile iron played in iron metabolism has largely been elucidated. Here we show that intracellular labile iron of hepatocytes has dual function in iron metabolism. It can induce hepatocytes expressing hepcidin via ER stress induced transcription factors on the one hand, on the other hand stimulate BMP2 and BMP6 expression of liver sinusoidal endothelial cells (LSECs) though TNFα secreted by hepatocytes to further regulate iron metabolism. Blockade of TNFα could dysregulate the iron metabolism during iron overload. Our findings reveal the important role of intracellular labile iron in iron metabolism and represent a novel way to modulate iron metabolism during iron overload. HepG2 mRNA profiles of DMOS, 8HQ, FAC and 8HQ/FAC treated HepG2 cells