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Hepatology International

, Volume 4, Issue 4, pp 741–748 | Cite as

Effects of nuclear receptor FXR on the regulation of liver lipid metabolism in patients with non-alcoholic fatty liver disease

  • Zhao-Xia Yang
  • Wei ShenEmail author
  • Hang Sun
Original Article

Abstract

Objective

The aim of this study was to explore the role of farnesoid X receptor (FXR) in liver lipid metabolism of non-alcoholic fatty liver disease (NAFLD) patients.

Methods

In this study, pathology and clinical criteria confirmed NAFLD in patients. Fatty acid synthetase (FAS)-positive liver cells were visualized by laser scanning confocal microscopy. Levels of FXR, liver X receptor (LXR), sterol regulatory element binding protein 1C (SREBP-1C), and small heterodimer partner (SHP) proteins were detected by Western blot. FXR, LXR, and SHP mRNA levels were measured by real-time PCR.

Results

In patients with NAFLD, a significant positive relationship between the degree of hepatic steatosis and serum triglycerides and cholesterol (correlation coefficient > 0.5, P < 0.05) was seen. The NAFLD patients had more FAS protein in liver, which suggests that there could have been more of fatty acid synthesis in hepatic cells (P < 0.05). The levels of FXR protein and mRNA were decreased in patients with NAFLD (P < 0.05), while those of LXR and SREBP-1C were increased (P < 0.05). The levels of SREBP-1C positively correlated with the degree of hepatic steatosis. There were no differences between the levels of SHP protein and mRNA both in NAFLD patients and normal controls (P > 0.05).

Conclusion

Our data showed that the decreased expression of hepatic FXR is associated with an increased expression of LXR, SREBP-1C, and hepatic triglyceride synthesis; furthermore, increased SREBP-1C is associated with the degree of hepatic steatosis in the NAFLD patients.

Keywords

FXR Human NAFLD Lipid metabolism 

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Copyright information

© Asian Pacific Association for the Study of the Liver 2010

Authors and Affiliations

  1. 1.Department of Gastroenterology and HepatologyThe Second Affiliated Hospital Chongqing Medical UniversityChongqingChina
  2. 2.Institute for Viral Hepatitis of Chongqing Medical University, Chongqing Medical UniversityChongqingChina

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