In adults,the hepatobiliary system,together with the kidney,constitute the main routes for the elimination of several endogenous and xenobiotic compounds into bile and urine,respectively.However,during intrauterine li...In adults,the hepatobiliary system,together with the kidney,constitute the main routes for the elimination of several endogenous and xenobiotic compounds into bile and urine,respectively.However,during intrauterine life the biliary route of excretion for cholephilic compounds,such as bile acids and biliary pigments,is very poor.Although very early in pregnancy the fetal liver produces bile acids,bilirubin and biliverdin,these compounds cannot be efficiently eliminated by the fetal hepatobiliary system,owing to the immaturity of the excretory machinery in the fetal liver.Therefore,the potentially harmful accumulation of cholephilic compounds in the fetus is prevented by their elimination across the placenta.Owing to the presence of detoxifying enzymes and specifi c transport systems at different locations of the placental barrier,such as the endothe-lial cells of chorionic vessels and trophoblast cells,this organ plays an important role in the hepatobiliary-like function during intrauterine life.The relevance of this excretory function in normal fetal physiology is evident in situations where high concentrations of biliary compounds are accumulated in the mother.This may result in oxidative stress and apoptosis,mainly in the placenta and fetal liver,which might affect normal fetal development and challenge the fate of the pregnancy.The present article reviews current knowledge of the mechanisms underlying the hepatobiliary function of the fetal-placental unit and the repercussions of several pathological conditions on this tandem.展开更多
基金Supported in part by The Instituto de Salud Carlos Ⅲ,FIS (GrantPI051547)the Junta de Castilla y Leon (Grants SA021B06,SA033A08,SA03508 and SA03608)+1 种基金SpainMinisterio de Ciencia y Tecnologia,Plan Nacional de Investigacion Cientifica,Desarrollo e Innovacion Tecnologica (Grant BFU2006-12577),Spain
文摘In adults,the hepatobiliary system,together with the kidney,constitute the main routes for the elimination of several endogenous and xenobiotic compounds into bile and urine,respectively.However,during intrauterine life the biliary route of excretion for cholephilic compounds,such as bile acids and biliary pigments,is very poor.Although very early in pregnancy the fetal liver produces bile acids,bilirubin and biliverdin,these compounds cannot be efficiently eliminated by the fetal hepatobiliary system,owing to the immaturity of the excretory machinery in the fetal liver.Therefore,the potentially harmful accumulation of cholephilic compounds in the fetus is prevented by their elimination across the placenta.Owing to the presence of detoxifying enzymes and specifi c transport systems at different locations of the placental barrier,such as the endothe-lial cells of chorionic vessels and trophoblast cells,this organ plays an important role in the hepatobiliary-like function during intrauterine life.The relevance of this excretory function in normal fetal physiology is evident in situations where high concentrations of biliary compounds are accumulated in the mother.This may result in oxidative stress and apoptosis,mainly in the placenta and fetal liver,which might affect normal fetal development and challenge the fate of the pregnancy.The present article reviews current knowledge of the mechanisms underlying the hepatobiliary function of the fetal-placental unit and the repercussions of several pathological conditions on this tandem.
