The effects of ghrelin on hepatic oxidative stress and Akt/GSK3β signaling pathway in high-fat diet-fed rats

Abstract

Abstract: Objective To investigate the effect of ghrelin on hepatic oxidative stress and Akt/GSK3β signaling pathway in rats fed with high-fat diet.Methods Male Wistar rats were randomly divided into normal control (NC) group, high-fat diet (HFD) group and ghrelin group (n=10 per group). Rats in NC group were fed with normal diet, while rats in both HFD and ghrelin group were fed with HFD for 6 weeks. Then, rats in NC group and HFD group were treated with saline for 4 weeks, while rats in ghrelin group were injected with ghrelin twice intraperitoneally at dose of 60 μg/kg for 4 weeks. At the end of the experiment, serum levels of alanine aminotransferase (ALT), triglycerides (TG) and total cholesterol (TC) were detected, and superoxide dismutase (SOD) and malondialdehyde (MDA) in liver homogenate were analyzed. Expressions of Akt and GSK3β mRNA in liver were detected using real-time PCR (RT-PCR). Results Wet weight of liver, serum TG and TC in HFD group were obviously higher than those in ghrelin group (P<0.05). Compared with those in HFD group, SOD level was higher (P<0.05) while MDA level was slightly lower (P>0.05) in ghrelin group. Ghrelin treatment enhanced the expression of Akt (P>0.05) and GSK3β (P<0.05).Conclusion Ghrelin could reduce hepatic oxidative stress in HFD-fed rats, which might be related to its effect on Akt/GSK3β pathway.

Key words: Ghrelin, NAFLD, High-fat diet, Oxidative stress, Akt/GSK3β pathway

LI Wen-song, CHEN Li-yan, BI Man-ru, YAN Bing-zhu, KANG Lan, YANG Peng-fei, WANG Xiao-ren, YANG Bao-shan.. The effects of ghrelin on hepatic oxidative stress and Akt/GSK3β signaling pathway in high-fat diet-fed rats[J]. Chinese Hepatolgy, 2017, 22(7): 597-601.

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