Hepatotrophic factors and liver regeneration. Part I: the role of hormones

Abstract

Regarding the cell proliferative process, hormones can show different actions when reach tissue receptors. HGF, TGF-alpha, IL-6, TNF-alpha, norepinefrin, EGF and insulin are known to be the main factors connected to liver growth. GH enhances DNA synthesis and gene expression of HGF as well as stimulates liver to produce growth factors. Thyroid hormones improve hepatocyte’s proliferative capacity. Insulin isn’t a primary mitogenic but enhances regenerative stimulation started by epinephrine and norepinephrine. Norepinephrine amplifies mitogenic signals of EGF and HGF. Moreover induces EGF secretion and antagonizes inhibitory efects of TGF-beta 1. Glucagon doesn’t produce effects alone but, probably participates of DNA synthesis and homeostasic process by wich glicemia is kept steady during regeneration. Finaly, there are clues that gastrin may promote hepatotrophic effects.

Hepatotrophic factors; Hormones; Insulin; Glucagon; Triiodothyronin