This manuscript summarizes recent data showing that estrogens and their receptors play an important role in modulating cholangiocyte proliferation. We have recently demonstrated that rat cholangiocytes express both estrogen receptors (ER)-α and -β subtypes, while hepatocytes only express ER-α. ER and especially the ER-β subtype, are overexpressed in cholangiocytes proliferating after bile duct ligation (BDL) in the rat, in association with enlarged bile duct mass and with enhanced estradiol serum levels. Cholangiocyte proliferation, during BDL, is impaired by estrogen antagonists (tamoxifen, ICI 182,780) which furthermore, induce the overexpression of Fas antigen and activate apoptosis of proliferating cholangiocytes. 17β-estradiol stimulates, in vitro cholangiocyte proliferation, and this effect is individually blocked by tamoxifen or ICI 182,780. Cholangiocyte proliferation during BDL was associated with an enhanced protein expression of phosphorylated extracellular regulated kinases (ERK)1/2 which is, in contrast, negatively modulated by tamoxifen in association with its antiproliferative effect. This indicates a major involvement of the ERK system in the estrogen modulation of cholangiocyte proliferation.
Alfa and beta estrogen receptors and the biliary tree / D. Alvaro, G. Alpini, P. Onori, A. Franchitto, S. Glaser, G. Le Sage, F. Folli, A. Attili, E. Gaudio. - In: MOLECULAR AND CELLULAR ENDOCRINOLOGY. - ISSN 0303-7207. - 193:1-2(2002), pp. 105-108. ((Intervento presentato al convegno Estrogen 2001 Congress tenutosi a Modena nel 2001.
|Titolo:||Alfa and beta estrogen receptors and the biliary tree|
FOLLI, FRANCO [Writing – Review & Editing]
|Parole Chiave:||cholangiocytes; proliferation; apoptosis; cholestasis; estrogens; estrogen receptors|
|Settore Scientifico Disciplinare:||Settore MED/09 - Medicina Interna|
|Data di pubblicazione:||2002|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/S0303-7207(02)00103-X|
|Appare nelle tipologie:||01 - Articolo su periodico|