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Arch Toxicol ; 94(2): 589-607, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894354

RESUMO

Anabolic-androgenic steroids are testosterone derivatives, used by body-builders to increase muscle mass. Epistane (EPI) is an orally administered 17α-alkylated testosterone derivative with 2a-3a epithio ring. We identified four individuals who, after EPI consumption, developed long-lasting cholestasis. The bile acid (BA) profile of three patients was characterized, as well the molecular mechanisms involved in this pathology. The serum BA pool was increased from 14 to 61-fold, basically on account of primary conjugated BA (cholic acid (CA) conjugates), whereas secondary BA were very low. In in vitro experiments with cultured human hepatocytes, EPI caused the accumulation of glycoCA in the medium. Moreover, as low as 0.01 µM EPI upregulated the expression of key BA synthesis genes (CYP7A1, by 65% and CYP8B1, by 67%) and BA transporters (NTCP, OSTA and BSEP), and downregulated FGF19. EPI increased the uptake/accumulation of a fluorescent BA analogue in hepatocytes by 50-70%. Results also evidenced, that 40 µM EPI trans-activated the nuclear receptors LXR and PXR. More importantly, 0.01 µM EPI activated AR in hepatocytes, leading to an increase in the expression of CYP8B1. In samples from a human liver bank, we proved that the expression of AR was positively correlated with that of CYP8B1 in men. Taken together, we conclude that EPI could cause cholestasis by inducing BA synthesis and favouring BA accumulation in hepatocytes, at least in part by AR activation. We anticipate that the large phenotypic variability of BA synthesis enzymes and transport genes in man provide a putative explanation for the idiosyncratic nature of EPI-induced cholestasis.


Assuntos
Ácidos e Sais Biliares/sangue , Colestase/induzido quimicamente , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Congêneres da Testosterona/toxicidade , Adulto , Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Colestase/metabolismo , Ácido Cólico/metabolismo , Feminino , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Masculino , Receptores Androgênicos/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/genética , Esteroide 12-alfa-Hidroxilase/genética , Esteroide 12-alfa-Hidroxilase/metabolismo , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
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