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Molecular mechanism of hepatic steatosis: pathophysiological role of autophagy

Published online by Cambridge University Press:  08 August 2016

Kewei Wang
Kewei Wang*
Affiliation:
Departments of Surgery, University of Illinois College of Medicine, One Illini Drive, Peoria, IL 61605, USA
*
*Corresponding author: Kewei Wang, Departments of Surgery, University of Illinois College of Medicine, One Illini Drive, Peoria, IL 61605, USA. Tel: 309-680-8617; E-mail: [email protected]
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Abstract

Steatosis is an early characteristic in the pathogenesis of fatty liver disease (FLD). Mechanisms of hepatic steatosis are aetiology-dependent. Activation of autophagy in liver ameliorates hepatic steatosis. A modulation of hepatic autophagy affects the degree of hepatocyte steatosis and the progression of FLD as demonstrated by pre-clinical models and clinical trials. This review summarises recent advances on pathophysiological roles of autophagy in hepatic lipid metabolism. A comprehensive regulation of autophagic networks holds promise for the improvement of hepatic steatosis. Autophagic signalling pathway may be a novel therapeutic target against FLD.

Highlights:

  • • Hepatic steatosis is a pathological condition wherein vacuoles of triglyceride (TG) fat are overaccumulated in liver because of abnormal metabolism of lipids.

  • • Hepatic autophagy regulates lipid metabolism as demonstrated by macrolipophagy in response to starvation and hepatic overabundance of TG in obesity.

  • • Autophagic signals are closely associated with apoptotic pathways. There is distinctive relationship between hepatic autophagy and apoptosis, which affects the progression of fatty liver.

  • • Regulation of autophagic process can be a novel therapeutic strategy for fatty liver disease.

Type
Review
Information
Expert Reviews in Molecular Medicine , Volume 18 , 2016 , e14
Copyright
Copyright © Cambridge University Press 2016 

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