NADPH OXIDASE-GENERATED REACTIVE OXYGEN SPECIES ARE INVOLVED IN ESTRADIOL 17ß-D-GLUCURONIDE-INDUCED CHOLESTASIS.

SALAS, GIMENA; LITTA, ALEN A; MEDEOT, ANABELA C.; SCHUCK, VIRGINIA S.; ANDERMATTEN, ROMINA B.; MISZCZUK, GISEL S.; CIRIACI, NADIA; RAZZORI, MARIA VALERIA; BAROSSO, ISMAEL R.; SANCHEZ POZZI, ENRIQUE J.; ROMA, MARCELO G.; BASIGLIO, CECILIA L.; CROCENZI, FERNANDO A.

BIOCHIMIE

ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER

Lugar: Paris; Año: 2024

0300-9084

The endogenous metabolite of estradiol, estradiol 17β-D-glucuronide (E17G), is considered the main responsible of the intrahepatic cholestasis of pregnancy. E17G alters the activity of canalicular transporters through a signaling pathway-dependent cellular internalization, phenomenon that was attributed to oxidative stress in different cholestatic conditions. However, there are no reports involving oxidative stress in E17G-induced cholestasis, representing this the aim of our work. Using polarized hepatocyte cultures, we showed that antioxidant compounds prevented E17G-induced Mrp2 activity alteration, being this alteration equally prevented by the NADPH oxidase (NOX) inhibitor apocynin. The model antioxidant N-acetyl- cysteine prevented, in isolated and perfused rat livers, E17G-induced impairment of bile flow and Mrp2 activity, thus confirming the participation of reactive oxygen species (ROS) in this cholestasis. In primary cultured hepatocytes, pretreatment with specific inhibitors of ERK1/2 and p38MAPK impeded E17G-induced ROS production; contrarily, NOX inhibition did not affect ERK1/2 and p38MAPK phosphorylation. Both, knockdown of p47phox by siRNA and preincubation with apocynin in sandwich-cultured rat hepatocytes significantly prevented E17G-induced internalization of Mrp2, suggesting a crucial role for NOX in this phenomenon.Concluding, E17G-induced cholestasis is partially mediated by NOX-generated ROS through internalization of canalicular transporters like Mrp2, being ERK1/2 and p38MAPK necessary for NOX activation.