The Unfolded Protein Response in Fatty Liver Disease

Anne Henkel; Richard M. Green

doi:10.1055/s-0033-1358522

Seminars in Liver Disease, Table of Contents

Semin Liver Dis 2013; 33(04): 321-329
DOI: 10.1055/s-0033-1358522

Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

The Unfolded Protein Response in Fatty Liver Disease

Authors

Anne Henkel

¹Division of Gastroenterology and Hepatology, Section of Hepatology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
Richard M. Green

²Division of Gastroenterology and Hepatology, Section of Hepatology, Northwestern University Feinberg School of Medicine, Chicago, Illinois

Abstract

The unfolded protein response (UPR) is a protective cellular response activated under conditions of endoplasmic reticulum (ER) stress. The hepatic UPR is activated in several forms of liver disease including nonalcoholic fatty liver disease (NAFLD). Recent data defining the role of the UPR in hepatic lipid metabolism have identified molecular mechanisms that may underlie the association between UPR activation and NAFLD. It has become increasingly evident that the IRE1α/Xbp1 pathway of the UPR is critical for hepatic lipid homeostasis, and dysregulation of this evolutionarily conserved pathway is associated with human nonalcoholic steatohepatitis (NASH). Although increasing evidence has delineated the importance of UPR pathway signaling in fatty liver disorders, the regulation of the hepatic UPR in normal physiology and fatty liver disorders remains incompletely understood. Understanding the role of the UPR in hepatic lipid metabolism may lead to the identification of novel therapeutic targets for the treatment of NAFLD.

Keywords

unfolded protein response - hepatic lipid metabolism - fatty liver - endoplasmic reticulum stress

Full Text

References

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