What is the function of the liver?

In the embryo, the liver is responsible for the production of blood cells after yolc sac hematopoiesis. The figure above is an illustration of the mature liver, which is responsible for glycogen storage and the production of serum albumin, blood cells, and bile (1).

Picture Credit: (1)

Differentiation of mature liver occurs through a series of inductions. The focus of most research is on the first induction of endoderm into hepatic endoderm. FGFs are critical to the initial differentiation of liver cells. Endoderm tissue expresses FGF receptors 1 and 4 (12). In vivo, endodermal cells in contact with cardiac mesoderm undergo hepatogenesis. Cardiac mesoderm expresses FGF1, FGF2, and FGF8b. The same signaling molecules can be used to form hepatic cells in vitro. FGF's are also involved in neural development.

In vitro studies reveal that initiation of liver development occurs in two phases:

1) Hepatic induction - FGF1 and FGF2 induce the formation of albumin-producing liver from endoderm.

2) Induction of liver morphogenesis - FGF8b is thought to act in cooperation with another molecule in the morphogenesis phase to promote the outgrowth of endoderm associated with liver development in embryogenesis.

Recent research has proven that the pancreas and the liver share a common origin in embryogenesis.

Picture Credit: (12)