Involvement of adenosine monophosphate-activated protein kinase in the influence of timed high-fat evening diet on the hepatic clock and lipogenic gene expression in mice

卷:35

Huang, Yan ; Zhu, Zengyan ; Xie, Meilin ; Xue, Jie

关键词: Adenosine monophosphate-activated protein kinase;    Clock genes;    Peroxisome proliferator-activated receptor alpha;    Lipogenic genes;    Fatty liver;    High-fat diet;   

DOI  :  10.1016/j.nutres.2015.06.009

学科分类：食品科学和技术

【 摘 要 】

A high-fat diet may result in changes in hepatic clock gene expression, but potential mechanisms are not yet elucidated. Adenosine monophosphate activated protein kinase (AMPK) is a serine/threonine protein kinase that is recognized as a key regulator of energy metabolism and certain clock genes. Therefore, we hypothesized that AMPK may be involved in the alteration of hepatic clock gene expression under a high-fat environment. This study aimed to examine the effects of timed high-fat evening diet on the activity of hepatic AMPK, clock genes, and lipogenic genes. Mice with hyperlipidemic fatty livers were induced by orally administering high-fat milk via gavage every evening (19:00-20:00) for 6 weeks. Results showed that timed high-fat diet in the evening not only decreased the hepatic AMPK protein expression and activity but also disturbed its circadian rhythm. Accordingly, the hepatic clock genes, including clock, brain-muscle-Arnt-like 1, cryptochrome 2, and period 2, exhibited prominent changes in their expression rhythms and/or amplitudes. The diurnal rhythms of the messenger RNA expression of peroxisome proliferator activated receptor a, acetyl-CoA carboxylase la, and carnitine palmitoyltransferase 1 were also disrupted; the amplitude of peroxisome proliferator activated receptor gamma coactivator la was significantly decreased at 3 time points, and fatty liver was observed. These findings demonstrate that timed high-fat diet at night can change hepatic AMPK protein levels, activity, and circadian rhythm, which may subsequently alter the circadian expression of several hepatic clock genes and finally result in the disorder of hepatic lipogenic gene expression and the formation of fatty liver. (C) 2015 Elsevier Inc. All rights reserved.