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Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD

  • Authors:
    • Chunwei Cheng
    • Xiaoling Deng
    • Keshu Xu
  • View Affiliations / Copyright

    Affiliations: Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
    Copyright: © Cheng et al. This is an open access article distributed under the terms of Creative Commons Attribution License.
  • Pages: 1877-1886
    |
    Published online on: January 16, 2018
       https://doi.org/10.3892/ijmm.2018.3389
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Abstract

Sterol regulatory element binding protein‑2 (SREBP‑2) is an important transcription factor in lipid homeostasis. A previous study showed that SREBP‑2 also activated autophagic genes during cell‑sterol depletion. Alterations in autophagy are reported to be involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). However, whether the regulation of SREBP‑2 restores dysfunctional autophagy in hepatocytes during NAFLD remains to be elucidated. In the present study, a steatosis model was established with palmitic acid (PA) treatment at the indicated times and concentrations. Autophagosomes in hepatocytes were visualized by confocal microscopy after transfection with a tandem GFP‑mCherry‑LC3 construct. Autophagy‑associated protein levels were analyzed by western blot analysis. Loss‑ and gain‑of‑function studies were performed to examine the role of SREBP‑2 in the regulation of hepatocyte autophagy. It was demonstrated that PA induced autophagy and enhanced autophagic flux at the early stage, whereas prolonged treatment with PA resulted in dysfunction of autophagy in the PA‑induced steatotic hepatocytes. In addition, different cellular models presented with differing dysfunctional autophagy in response to fatty acid overload. It was also confirmed that SREBP‑2 regulated autophagy‑related gene expression in hepatocytes, and it was shown that the overexpression of SREBP‑2 increased the expression of autophagy‑related genes, but did not affect the inhibition of the autophagic flux in lipid‑overloaded HL‑7702 cells. By contrast, increased SREBP‑2 partly restored the inhibited autophagic activity in lipid‑overloaded hepatoma HepG2 cells. Taken together, the present study demonstrated that autophagic function was impaired in lipid‑overloaded human hepatocytes, and the differential effect of PA on autophagy was associated with the duration of PA and the cell type. Under these conditions, the overexpression of SREBP‑2 alleviated the inhibited autophagic activity rather than the inhibition of autophagic flux. Consequently, the results indicated that restoration of autophagy dysfunction via the regulation of SREBP‑2 may be a potential therapeutic target for the treatment of NAFLD.
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1 

Brunt EM, Wong VW, Nobili V, Day CP, Sookoian S, Maher JJ, Bugianesi E, Sirlin CB, Neuschwander-Tetri BA and Rinella ME: Nonalcoholic fatty liver disease. Nat Rev Dis Primers. 1:150802015. View Article : Google Scholar : PubMed/NCBI

2 

Wang FS, Fan JG, Zhang Z, Gao B and Wang HY: The global burden of liver disease: The major impact of China. Hepatology. 60:2099–2108. 2014. View Article : Google Scholar : PubMed/NCBI

3 

Cheung O and Sanyal AJ: Recent advances in nonalcoholic fatty liver disease. Curr Opin Gastroenterol. 26:202–208. 2010. View Article : Google Scholar : PubMed/NCBI

4 

Neuschwander-Tetri BA: Hepatic lipotoxicity and the pathogenesis of nonalcoholic steatohepatitis: The central role of nontriglyceride fatty acid metabolites. Hepatology. 52:774–788. 2010. View Article : Google Scholar : PubMed/NCBI

5 

Li S, Li J, Shen C, Zhang X, Sun S, Cho M, Sun C and Song Z: Tert-Butylhydroquinone (tBHQ) protects hepatocytes against lipotoxicity via inducing autophagy independently of Nrf2 activation. Biochim Biophys Acta. 1841:22–33. 2014. View Article : Google Scholar

6 

Wu J, Wu JJ, Yang LJ, Wei LX and Zou DJ: Rosiglitazone protects against palmitate-induced pancreatic beta-cell death by activation of autophagy via 5′-AMP-activated protein kinase modulation. Endocrine. 44:87–98. 2013. View Article : Google Scholar

7 

Ryter SW, Cloonan SM and Choi AM: Autophagy: A critical regulator of cellular metabolism and homeostasis. Mol Cells. 36:7–16. 2013. View Article : Google Scholar : PubMed/NCBI

8 

Singh R, Kaushik S, Wang Y, Xiang Y, Novak I, Komatsu M, Tanaka K, Cuervo AM and Czaja MJ: Autophagy regulates lipid metabolism. Nature. 458:1131–1135. 2009. View Article : Google Scholar : PubMed/NCBI

9 

Fukuo Y, Yamashina S, Sonoue H, Arakawa A, Nakadera E, Aoyama T, Uchiyama A, Kon K, Ikejima K and Watanabe S: Abnormality of autophagic function and cathepsin expression in the liver from patients with non-alcoholic fatty liver disease. Hepatol Res. 44:1026–1036. 2014. View Article : Google Scholar

10 

González-Rodríguez Á, Mayoral R, Agra N, Valdecantos MP, Pardo V, Miquilena-Colina ME, Vargas-Castrillón J, Lo Iacono O, Corazzari M, Fimia GM, et al: Impaired autophagic flux is associated with increased endoplasmic reticulum stress during the development of NAFLD. Cell Death Dis. 5:e11792014. View Article : Google Scholar : PubMed/NCBI

11 

Yang L, Li P, Fu S, Calay ES and Hotamisligil GS: Defective hepatic autophagy in obesity promotes ER stress and causes insulin resistance. Cell Metab. 11:467–478. 2010. View Article : Google Scholar : PubMed/NCBI

12 

Liu HY, Han J, Cao SY, Hong T, Zhuo D, Shi J, Liu Z and Cao W: Hepatic autophagy is suppressed in the presence of insulin resistance and hyperinsulinemia: Inhibition of FoxO1-dependent expression of key autophagy genes by insulin. J Biol Chem. 284:31484–31492. 2009. View Article : Google Scholar : PubMed/NCBI

13 

Czaja MJ: Functions of autophagy in hepatic and pancreatic physiology and disease. Gastroenterology. 140:1895–1908. 2011. View Article : Google Scholar : PubMed/NCBI

14 

Koga H, Kaushik S and Cuervo AM: Altered lipid content inhibits autophagic vesicular fusion. FASEB J. 24:3052–3065. 2010. View Article : Google Scholar : PubMed/NCBI

15 

Inami Y, Yamashina S, Izumi K, Ueno T, Tanida I, Ikejima K and Watanabe S: Hepatic steatosis inhibits autophagic proteolysis via impairment of autophagosomal acidification and cathepsin expression. Biochem Biophys Res Commun. 412:618–625. 2011. View Article : Google Scholar : PubMed/NCBI

16 

Park HW, Park H, Semple IA, Jang I, Ro SH, Kim M, Cazares VA, Stuenkel EL, Kim JJ, Kim JS and Lee JH: Pharmacological correction of obesity-induced autophagy arrest using calcium channel blockers. Nat Commun. 5:48342014. View Article : Google Scholar : PubMed/NCBI

17 

Seo YK, Jeon TI, Chong HK, Biesinger J, Xie X and Osborne TF: Genome-wide localization of SREBP-2 in hepatic chromatin predicts a role in autophagy. Cell Metab. 13:367–375. 2011. View Article : Google Scholar : PubMed/NCBI

18 

Livak KJ and Schmittgen TD: Analysis of relative gene expression data using real-time quantitative PCR and the 2−ΔΔC T method. Methods. 25:402–408. 2001. View Article : Google Scholar

19 

Pan X, Wang P, Luo J, Wang Z, Song Y, Ye J and Hou X: Adipogenic changes of hepatocytes in a high-fat diet-induced fatty liver mice model and non-alcoholic fatty liver disease patients. Endocrine. 48:834–847. 2015. View Article : Google Scholar

20 

Choi SE, Lee SM, Lee YJ, Li LJ, Lee SJ, Lee JH, Kim Y, Jun HS, Lee KW and Kang Y: Protective role of autophagy in palmitate-induced INS-1 beta-cell death. Endocrinology. 150:126–134. 2009. View Article : Google Scholar

21 

Mei S, Ni HM, Manley S, Bockus A, Kassel KM, Luyendyk JP, Copple BL and Ding WX: Differential roles of unsaturated and saturated fatty acids on autophagy and apoptosis in hepatocytes. J Pharmacol Exp Ther. 339:487–498. 2011. View Article : Google Scholar : PubMed/NCBI

22 

Mizushima N, Yoshimori T and Levine B: Methods in mammalian autophagy research. Cell. 140:313–326. 2010. View Article : Google Scholar : PubMed/NCBI

23 

Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, Adachi H, Adams CM, Adams PD, Adeli K, et al: Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition). Autophagy. 12:1–222. 2016. View Article : Google Scholar : PubMed/NCBI

24 

Jaishy B, Zhang Q, Chung HS, Riehle C, Soto J, Jenkins S, Abel P, Cowart LA, Van Eyk JE and Abel ED: Lipid-induced NOX2 activation inhibits autophagic flux by impairing lysosomal enzyme activity. J Lipid Res. 56:546–561. 2015. View Article : Google Scholar :

25 

Osborne TF and Espenshade PJ: Evolutionary conservation and adaptation in the mechanism that regulates SREBP action: What a long, strange tRIP it's been. Genes Dev. 23:2578–2591. 2009. View Article : Google Scholar : PubMed/NCBI

26 

Shao W and Espenshade PJ: Expanding roles for SREBP in metabolism. Cell Metab. 16:414–419. 2012. View Article : Google Scholar : PubMed/NCBI

27 

Wong TY, Lin SM and Leung LK: The flavone luteolin suppresses SREBP-2 expression and Post-translational activation in hepatic cells. PLoS One. 10:e01356372015. View Article : Google Scholar : PubMed/NCBI

28 

Levine B and Kroemer G: Autophagy in the pathogenesis of disease. Cell. 132:27–42. 2008. View Article : Google Scholar : PubMed/NCBI

29 

Wang K: Autophagy and apoptosis in liver injury. Cell Cycle. 14:1631–1642. 2015. View Article : Google Scholar : PubMed/NCBI

30 

Lavallard VJ and Gual P: Autophagy and non-alcoholic fatty liver disease. Biomed Res Int. 2014:1201792014. View Article : Google Scholar : PubMed/NCBI

31 

Mizushima N and Levine B: Autophagy in mammalian development and differentiation. Nat Cell Biol. 12:823–830. 2010. View Article : Google Scholar : PubMed/NCBI

32 

Codogno P and Meijer AJ: Autophagy: A potential link between obesity and insulin resistance. Cell Metab. 11:449–451. 2010. View Article : Google Scholar : PubMed/NCBI

33 

Tan SH, Shui G, Zhou J, Li JJ, Bay BH, Wenk MR and Shen HM: Induction of autophagy by palmitic acid via protein kinase C-mediated signaling pathway independent of mTOR (mammalian target of rapamycin). J Biol Chem. 287:14364–14376. 2012. View Article : Google Scholar : PubMed/NCBI

34 

Ogata M, Hino S, Saito A, Morikawa K, Kondo S, Kanemoto S, Murakami T, Taniguchi M, Tanii I, Yoshinaga K, et al: Autophagy is activated for cell survival after endoplasmic reticulum stress. Mol Cell Biol. 26:9220–9231. 2006. View Article : Google Scholar : PubMed/NCBI

35 

Yorimitsu T and Klionsky DJ: Endoplasmic reticulum stress: A new pathway to induce autophagy. Autophagy. 3:160–162. 2007. View Article : Google Scholar : PubMed/NCBI

36 

Park M, Sabetski A, Kwan Chan Y, Turdi S and Sweeney G: Palmitate induces ER stress and autophagy in H9c2 cells: Implications for apoptosis and adiponectin resistance. J Cell Physiol. 230:630–639. 2015. View Article : Google Scholar

37 

Cai N, Zhao X, Jing Y, Sun K, Jiao S, Chen X, Yang H, Zhou Y and Wei L: Autophagy protects against palmitate-induced apoptosis in hepatocytes. Cell Biosci. 4:282014. View Article : Google Scholar : PubMed/NCBI

38 

Liu J, Chang F, Li F, Fu H, Wang J, Zhang S, Zhao J and Yin D: Palmitate promotes autophagy and apoptosis through ROS-dependent JNK and p38 MAPK. Biochem Biophys Res Commun. 463:262–267. 2015. View Article : Google Scholar : PubMed/NCBI

39 

Kim KY, Jang HJ, Yang YR, Park KI, Seo J, Shin IW, Jeon TI, Ahn SC, Suh PG, Osborne TF and Seo YK: Corrigendum: SREBP-2/PNPLA8 axis improves non-alcoholic fatty liver disease through activation of autophagy. Sci Rep. 6:357322016. View Article : Google Scholar

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Copy and paste a formatted citation
Spandidos Publications style
Cheng C, Deng X and Xu K: Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD. Int J Mol Med 41: 1877-1886, 2018.
APA
Cheng, C., Deng, X., & Xu, K. (2018). Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD. International Journal of Molecular Medicine, 41, 1877-1886. https://doi.org/10.3892/ijmm.2018.3389
MLA
Cheng, C., Deng, X., Xu, K."Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD". International Journal of Molecular Medicine 41.4 (2018): 1877-1886.
Chicago
Cheng, C., Deng, X., Xu, K."Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD". International Journal of Molecular Medicine 41, no. 4 (2018): 1877-1886. https://doi.org/10.3892/ijmm.2018.3389
Copy and paste a formatted citation
x
Spandidos Publications style
Cheng C, Deng X and Xu K: Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD. Int J Mol Med 41: 1877-1886, 2018.
APA
Cheng, C., Deng, X., & Xu, K. (2018). Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD. International Journal of Molecular Medicine, 41, 1877-1886. https://doi.org/10.3892/ijmm.2018.3389
MLA
Cheng, C., Deng, X., Xu, K."Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD". International Journal of Molecular Medicine 41.4 (2018): 1877-1886.
Chicago
Cheng, C., Deng, X., Xu, K."Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD". International Journal of Molecular Medicine 41, no. 4 (2018): 1877-1886. https://doi.org/10.3892/ijmm.2018.3389
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