Sortilin Deficiency Reduces Ductular Reaction, Hepatocyte Apoptosis, and Liver Fibrosis in Cholestatic-Induced Liver Injury.
Am J Pathol
; 187(1): 122-133, 2017 Jan.
Article
em En
| MEDLINE
| ID: mdl-27842214
ABSTRACT
Sortilin, a member of the vacuolar protein sorting 10 domain receptor family, traffics newly synthesized proteins from the trans-Golgi network to secretory pathways, endosomes, and cell surface. Sortilin-trafficked molecules, including IL-6 and acid sphingomyelinase (aSMase), mediate cholangiocyte proliferation and liver inflammation, hepatic stellate cell activation, hepatocyte apoptosis, and fibrosis. Based on these sortilin-regulated functions, we investigated its role in biliary damage leading to hepatocellular injury and fibrosis. Sortilin-/- mice displayed impaired inflammation and ductular reaction 3 days after bile duct ligation (BDL), as demonstrated by reduced cholangiocyte proliferation and activation and reduced serum IL-6. Interestingly, liver fibrosis was reduced in Sortilin-/- mice after both BDL and carbon tetrachloride treatment, in line with attenuated in vitro activation of Sortilin-/- hepatic stellate cells. Sortilin-/- hepatic aSMase activity was reduced in the BDL and carbon tetrachloride models and accompanied by reduced in vivo hepatocyte apoptosis. In addition, wild type (WT), but not Sortilin-/- hepatocytes, had increased aSMase-dependent susceptibility to bile acid-induced apoptosis in vitro. Mechanistically, short-term IL-6 neutralization in bile duct-ligated WT mice decreased hepatic inflammation and reactive cholangiocyte-derived cytokines and chemokines, without affecting fibrosis, whereas pharmacological inhibition of aSMase activity was not sufficient to attenuate hepatic fibrosis. Only combined IL-6 and aSMase inhibition significantly reduced fibrosis in bile duct-ligated WT mice. We conclude that sortilin regulates cholestatic liver damage and fibrosis via effects on both aSMase activity and serum IL-6.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Ductos Biliares
/
Colestase
/
Apoptose
/
Hepatócitos
/
Proteínas Adaptadoras de Transporte Vesicular
/
Fígado
/
Cirrose Hepática
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article