Inhibitory Effect of Tea (Camellia Sinensis (L.) O. Kuntze, Theaceae) Flower Extracts on Oleic Acid-Induced Hepatic Steatosis in Hepg2 Cells

Xinghai Zhang^{1, 2}, Ying Gao¹, Jinwei Xu^{1, 2}, Xiaohui Liu¹, Feng Jin^{1, 2}, Bo Li¹ and Youying Tu^1,

¹Department of Tea Science, College of Agriculture & Biotechnology, Zhejiang University, Hangzhou, China

²Department of Applied Engineering, Zhejiang Economic and Trade Polytechnic, Hangzhou, China

Cite this paper:
Xinghai Zhang, Ying Gao, Jinwei Xu, Xiaohui Liu, Feng Jin, Bo Li and Youying Tu. Inhibitory Effect of Tea (Camellia Sinensis (L.) O. Kuntze, Theaceae) Flower Extracts on Oleic Acid-Induced Hepatic Steatosis in Hepg2 Cells. Journal of Food and Nutrition Research. 2014; 2(10):738-743. doi: 10.12691/jfnr-2-10-13

Abstract

Tea (Camellia sinensis (L.) O. Kuntze, Theaceae) flowers possess many physiological functions and have been used in traditional medicines for deodorization, skin care, cough suppressant and expectorant in China. However, there is little information about its effect on nonalcoholic fatty liver disease (NAFLD). In this study, an oleic acid-induced HepG2 cell model of steatosis was established, and the anti-NAFLD effects of tea flowers and the related mechanisms were investigated. Three tea flower extracts, 40% TFE, 80% TFE and TFRE couldn’t prevent triglyceride (TG) accumulation in oleic acid-treated HepG2 cells (p > 0.05), but significantly decreased the TG level in lipid-overloaded HepG2 cells after 48 h treatment (p < 0.05). RT-PCR analysis revealed that three tea flower extracts did not affect the mRNA levels of peroxisome proliferator-activated receptors α (PPARα) and Acyl-CoA oxidase-1 (ACOX-1) (p > 0.05), but up-regulated the mRNA level of carnitine palmitoyl-CoA transferase (CPT) (p < 0.05). Moreover, tea flower extracts could significantly reduce intracellular reactive oxygen species (ROS) level (p < 0.05). These results indicated tea flowers may be a potential natural resourse for the treatment of NAFLD.

Keywords:
tea flowers NAFLD triglyceride CPT ROS

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