Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2014 Aug 5;111(31):11437-42.
doi: 10.1073/pnas.1410741111. Epub 2014 Jul 15.

Comparative proteomic study reveals 17β-HSD13 as a pathogenic protein in nonalcoholic fatty liver disease

Wen Su  1 , Yang Wang  2 , Xiao Jia  1 , Wenhan Wu  3 , Linghai Li  4 , Xiaodong Tian  3 , Sha Li  1 , Chunjiong Wang  1 , Huamin Xu  1 , Jiaqi Cao  1 , Qifei Han  1 , Shimeng Xu  2 , Yong Chen  4 , Yanfeng Zhong  5 , Xiaoyan Zhang  6 , Pingsheng Liu  7 , Jan-Åke Gustafsson  8 , Youfei Guan  9
Affiliations
Comparative Study

Comparative proteomic study reveals 17β-HSD13 as a pathogenic protein in nonalcoholic fatty liver disease

Wen Su et al. Proc Natl Acad Sci U S A. .

Abstract

Nonalcoholic fatty liver disease (NAFLD) is characterized by a massive accumulation of lipid droplets (LDs). The aim of this study was to determine the function of 17β-hydroxysteroid dehydrogenase-13 (17β-HSD13), one of our newly identified LD-associated proteins in human subjects with normal liver histology and simple steatosis, in NAFLD development. LDs were isolated from 21 human liver biopsies, including 9 cases with normal liver histology (group 1) and 12 cases with simple steatosis (group 2). A complete set of LD-associated proteins from three liver samples of group 1 or group 2 were determined by 2D LC-MS/MS. By comparing the LD-associated protein profiles between subjects with or without NAFLD, 54 up-regulated and 35 down-regulated LD-associated proteins were found in NAFLD patients. Among them, 17β-HSD13 represents a previously unidentified LD-associated protein with a significant up-regulation in NAFLD. Because the 17β-HSD family plays an important role in lipid metabolism, 17β-HSD13 was selected for validating the proteomic findings and exploring its role in the pathogenesis of NAFLD. Increased hepatic 17β-HSD13 and its LD surface location were confirmed in db/db (diabetic) and high-fat diet-fed mice. Adenovirus-mediated hepatic overexpression of human 17β-HSD13 induced a fatty liver phenotype in C57BL/6 mice, with a significant increase in mature sterol regulatory element-binding protein 1 and fatty acid synthase levels. The present study reports an extensive set of human liver LD proteins and an array of proteins differentially expressed in human NAFLD. We also identified 17β-HSD13 as a pathogenic protein in the development of NAFLD.

Keywords: HSDI7β13; SCDR9; lipogenesis.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Fig. 1.
Fig. 1.
Purification and validation of LDs using immunoblot analysis. (A) Isolated human liver LDs were stained with Nile red and imagined by fluorescence microscope. Arrow points to a lipid droplet. (B) Silver-stained gel was used to compare the protein profiles of different subcellular fractions. (C) Proteins separated by SDS/PAGE were transferred to a PVDF membrane and immune blotted with indicated antibodies. The primary antibodies of ADRP, ACSL1, and CGI58 were used to confirm the enrichment of LDs. BIP (ER-specific marker), Tim23, and COX IV (mitochondrion-specific markers) were used to represent the indicated organelles. GAPDH was used to exclude contamination of cytosol. PNS, postnuclear supernatant; TM, total membrane.
Fig. 2.
Fig. 2.
Identification of LD-associated proteins which show altered expression in NAFLD livers versus control livers. (A) Equal protein loads of pooled LD fractions isolated from human livers with or without NAFLD were separated by SDS/PAGE and silver stained. The arrows indicate the bands selected, excised from the gel, and processed for 2D LC-MS/MS analyses. (B) Western blot analysis confirms up-regulation of ADRP and FAS in LD fraction of NAFLD shown in SI Appendix, Table S7. Silver staining served as an even loading control. (C) Real-time PCR analysis reveals that ADRP and FAS mRNA levels were significantly up-regulated. n = 7, *P < 0.05 vs. controls. β-Actin was used as an internal control. (D) Western blot assay of ADRP and FAS protein expression levels using whole-tissue lysates of control and fatty livers. eIF5 was used as an internal control.
Fig. 3.
Fig. 3.
LD surface localization of 17β-HSD13 in human liver and cultured hepatocytes. (A) Western blot analysis showing that 17β-HSD13 was markedly up-regulated in LD fraction of NAFLD. Silver staining served as an even loading control. (B) Immunoblot assay using whole liver lysates demonstrating that 17β-HSD13 was significantly up-regulated in fatty livers. (C) Immunostaining of 17β-HSD13 showing that 17β-HSD13 was localized at the surface of LDs in human livers. Note: More intense staining of 17β-HSD13 in fatty liver than control liver. (D) LD surface localization of GFP-tagged 17β-HSD13 (17β-HSD13–GFP) in Huh7 cells. Green: 17β-HSD13-GFP; Mauve: LipidTOX Deep Red; Blue: DAPI. (Scale bar, 1 µm.)
Fig. 4.
Fig. 4.
17β-HSD13 enhanced lipogenesis in mouse liver. (A and B) db/db mice and mice fed with a HFD, two murine fatty liver models, were used to examine 17β-HSD13 expression levels. (A) Western blot analysis of 17β-HSD13 protein expression levels in db/m and db/db mice. (B) Immunoblot analysis of 17β-HSD13 protein expression levels in normal diet and HFD-fed mice. (C) Hepatic overexpression of 17β-HSD13 via tail-vein administration of adenoviruses encoding 17β-HSD13 for 4 d resulted in a fatty liver phenotype as assessed by morphological examination (Upper) and Oil red O staining (Lower, magnification: 1,000×). Adenovirus expressing GFP (Ad-GFP) was used as a control. (D) Liver TG and CHO levels were tested 4 d after the adenovirus injection. Hepatic overexpression significantly increased liver TG and CHO contents. *P < 0.05 vs. Ad-GFP, n = 5. (E) Western blot analysis of protein involved in lipogenesis, including SREBP-1, FAS, and SCD1. (F) Quantitative analysis of 17β-HSD13 and the protein expression levels shown in C. *P < 0.05 and **P < 0.01 vs. Ad-GFP, n = 5.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Cohen JC, Horton JD, Hobbs HH. Human fatty liver disease: Old questions and new insights. Science. 2011;332(6037):1519–1523. - PMC - PubMed
    1. Qureshi K, Abrams GA. Metabolic liver disease of obesity and role of adipose tissue in the pathogenesis of nonalcoholic fatty liver disease. World J Gastroenterol. 2007;13(26):3540–3553. - PMC - PubMed
    1. Lawrence HR, et al. Novel and potent 17beta-hydroxysteroid dehydrogenase type 1 inhibitors. J Med Chem. 2005;48(8):2759–2762. - PubMed
    1. Bulla GA, et al. Genome-wide analysis of hepatic gene silencing in hepatoma cell variants. Genomics. 2012;100(3):176–183. - PubMed
    1. Chang BH, et al. Protection against fatty liver but normal adipogenesis in mice lacking adipose differentiation-related protein. Mol Cell Biol. 2006;26(3):1063–1076. - PMC - PubMed

Publication types

MeSH terms