Research Paper

UVRAG deficiency exacerbates fasting-induced hepatic steatosis

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  • Bio-X Institutes, Key Laboratory for Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China

Received date: 2016-06-06

  Online published: 2018-06-28

Abstract

[Objective] Ultraviolet resistance-associated gene (UVRAG) is an autophagy-related protein with multiple functions. Previously that autophagic flux is impaired in UVRAG-deficient mice has been shown. Given that autophagy regulates lipid metabolism, the role of UVRAG in fasting-induced hepatic steatosis was sought to determined. [Methods and results] Wild type (WT) and UVARG-deficient mice were subjected to normal conditions or 24 h fasting. In normal conditions, Oil red O staining showed no difference in hepatic lipid accumulation between WT and UVRAG-deficient mice. However, UVRAG deficiency exacerbates fasting-induced hepatic lipid accumulation compared with WT controls. Real time reverse transcription-polymerize chain reaction (RT-PCR) showed that UVRAG deficiency had no effects on the expression of lipid metabolic gene including CD 36, FAS, CPT-1, PPAR and FGF 21 in normal and fasting conditions. Sterol regulatory element-binding protein 1 (SREBP-1), which was lower in the liver from UVRAG-deficient mice, was comparable between fasted UVRAG-deficient mice and WT controls. Moreover, no difference in AMPK activity was observed in the liver from WT and UVRAG-deficient mice in fasting conditions. Plasma triglyceride and free fatty acid concentration were elevated in fed and fasted UVRAG-deficient mice compared with corresponding WT controls. Plasma cholesterol concentration was not different between WT and UVRAG-deficient mice in normal and fasting conditions. UVRAG deficiency exacerbated fasting-induced reduction in plasma glucose concentration. [Conclusions] UVRAG deficiency exacerbates fasting-induced hepatic steatosis, which may be due to impaired autophagic flux and increased uptake of plasma free fatty acid.

Cite this article

HU Xiaowen, ZHANG Shasha, AN Lin, AMBER Naz, ZHU Hongxin . UVRAG deficiency exacerbates fasting-induced hepatic steatosis[J]. Journal of Shanghai University, 2018 , 24(3) : 467 -476 . DOI: 10.12066/j.issn.1007-2861.1811

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