Punicalagin Inhibits Palmitate Acid-induced Lipoapoptosis through Inhibition of ER Stress, and Activation of SIRT1/Autophagy in HepG2 Cells

Han Zhang¹, Hao Wu¹, Shutao Yin¹, Hongbo Hu¹ and Chong Zhao^1,

¹Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Haidian District, Beijing, China

Cite this paper:
Han Zhang, Hao Wu, Shutao Yin, Hongbo Hu and Chong Zhao. Punicalagin Inhibits Palmitate Acid-induced Lipoapoptosis through Inhibition of ER Stress, and Activation of SIRT1/Autophagy in HepG2 Cells. Journal of Food and Nutrition Research. 2020; 8(9):536-542. doi: 10.12691/jfnr-8-9-10

Abstract

Lipid metabolism balance plays a vital role in maintaining normal levels of sterols, triglycerides, and free fatty acids (FFA). Inhibiting FFA-induced lipotoxicity is considered a highly potential treatment for non-alcoholic fatty liver disease (NAFLD) and other lipid metabolism diseases. Punicalagin (PU), a pomegranate-derived polyphenol, has been found to effectively regulate lipid metabolism and prevent fatty liver, cardiovascular and other chronic diseases caused by lipid metabolism disorders. In the present study, we found that PU protects HepG2 cells from palmitic acid (PA)-induced lipapoptosis. Silent information regulator 1 (SIRT1) plays a key role in protecting against lipapoptosis in HepG2 cells. Knockdown of SIRT1 significantly diminished the protective effect of PU. Besides, PU could be able to reactivate weakened autophagy and inhibit PA-induced ER stress. Our findings supported that PU can effectively attenuate FFA-induced lipotoxicity via activating SIRT1/autophagy and inhibiting ER stress.

Keywords:
punicalagin palmitic acid lipotoxicity SIRT1 endoplasmic reticulum stress autophagy

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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