Aged Oolong Tea Reduces High-Fat Diet-Induced Fat Accumulation and Dyslipidemia by Regulating the AMPK/ACC Signaling Pathway

Abstract

While oolong tea (OT) has been shown to induce weight loss and reduce fat accumulation, the mechanisms remain poorly defined, especially for aged OT. In this study, five groups of mice (n = 9/group) were used including a normal diet with vehicle treatment, and a high-fat diet (HFD) with vehicle or the water extracts from aged OTs (EAOTs, three different storage years) by oral gavage at 1000 mg/kg·BW for 6 weeks. Body weight, fat accumulation, and serum biochemical parameters were used to evaluate obesity. The morphology of hepatocytes and adipocytes was analyzed by being stained with hematoxylin and eosin. The levels of p-AMPK, p-ACC (and non-phosphorylated versions), CPT-1 and FAS were determined by Western blotting and immunohistochemistry. EAOTs decreased HFD-induced body weight, fat accumulation, serum levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol, while enhancing the serum high-density lipoprotein cholesterol level. At the same time, EAOTs clearly alleviated fatty liver and reduced the size of adipocytes in the epididymal fat, especially in the 2006 group. Most importantly, EAOTs increased the phosphorylation of AMPK and ACC, and up-regulated the expression of CPT-1 but down-regulated the expression of fatty acid synthase, TNF-α and iNOS. Thus, EAOTs may inhibit obesity by up-regulating energy expenditure and fatty acid oxidation while inhibiting fatty acid synthesis and inflammation.

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“…Some of the most studied plants as natural pancreatic lipase inhibitors are different types of teas, such as oolong (Yuan et al, 2018), green (Nakayama et al, 2015;Seo et al, 2017) and black tea (Wang et al, 2017a(Wang et al, ,2017b. The identified polyphenols, e.g.…”

Kisspeptin-10 Promoting the Synthesis of Milk Fat by Inhibiting the AMPK/SIRT6 Signaling Pathway via the GPR54 in Bovine Mammary Epithelial Cells

“…Ginsenosides Rg1 reduces fat deposition in adipose tissue and 3T3-L1 cells by activating AMPK [34]. Aged Oolong Tea reduces fat deposits caused by a high-fat diet by activating AMPK [35]. In addition, the role of AMPK in the synthesis of milk fat in lactating cows has been introduced in some studies.…”

The Pharmacological Activity of Camellia sinensis (L.) Kuntze on Metabolic and Endocrine Disorders: A Systematic Review

“…The mouse adipocyte 3T3-L1 cell line has been extensively used to study the in vitro effect of tea extracts and its isolated compounds [71][72][73]. In obesity in vivo studies, C57BL/6J mice are the most widely animal model since they are susceptible to high fat diet-induced obesity [74,75]. Moreover, other experimental animal models have been used to investigate the effects of different kind of teas and isolated compounds on obesity including Wistar rats, Sprague-Dawley rats, and Swiss mice fed with a high fat diet [76,77].…”

“…This study revealed that all teas reduced body weight, total visceral fat volume, and liver lipid weight and, that green tea polyphenols and oolong tea polyphenols also increased adiponectin gene expression. Besides, oolong tea reduced body weight and fat accumulation by regulating fatty acid oxidation and energy expenditure [75]. Moreover, oolong tea, white tea, yellow tea, pu-erh tea, and black tea have also showed to decrease body weight, plasma triglycerides, white fat accumulation, and fatty acid synthesis and to increase energy expenditure, fatty acid oxidation, and fecal triglycerides excretion in Wistar rats, Sprague-Dawley rats and Swiss mice fed with a high fat diet [76,77].…”