Aquaporin-9 downregulation prevents steatosis in oleic acid-induced non-alcoholic fatty liver disease cell models

Wang,Chuan; Lv,Zi-Lan; Kang,Yu-Jun; Xiang,Ting-Xiu; Wang,Pi-Long; Jiang,Zheng

doi:10.3892/ijmm.2013.1502

Aquaporin-9 downregulation prevents steatosis in oleic acid-induced non-alcoholic fatty liver disease cell models

Authors:
- Chuan Wang
- Zi-Lan Lv
- Yu-Jun Kang
- Ting-Xiu Xiang
- Pi-Long Wang
- Zheng Jiang
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Affiliations: Department of Gastroenterology, The First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, P.R. China, Key Laboratory of Diagnostic Medicine Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400016, P.R. China
Published online on: September 19, 2013 https://doi.org/10.3892/ijmm.2013.1502
Pages: 1159-1165

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Abstract

Aquaporin-9 (AQP9) is an aquaglyceroporin that acts as the adipose glycerol channel. However, the role of AQP9 in steatosis in non-alcoholic fatty liver disease (NAFLD) has not yet been fully elucidated. In the present study, the coding sequence of the AQP9 gene was obtained from LO2 cells by RT-PCR, and cloned into the pEGFP-N1 vector. Short hairpin RNA (shRNA) targeting the AQP9 gene was inserted into the pGenesil-1 vector. Recombinant plasmids were confirmed by enzyme digestion and sequence analysis, and transfected into cell models (derived from LO2 cells) of oleic acid-induced NAFLD. Our results demonstrated that AQP9 recombinant plasmids can be effectively expressed in cell models of NAFLD. Furthermore, in comparison with the control group, AQP9 overexpression significantly increased intracellular lipid content, triglyceride (TG), free fatty acid (FFA) and glycerol levels; however, the silencing of AQP9 exerted the opposite effects. Taken together, recombinant plasmids used to induce AQP9 overexpression and to silence AQP9 expression were successfully constructed. AQP9 overexpression aggravated the degree of steatosis; however, the silencing of AQP9 alleviated these effects. Based on these data, we suggest that AQP9 may serve as a novel molecular target for therapeutic intervention in NAFLD.

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