Anti-obesity effects of boiled tuna extract in mice with obesity induced by a high-fat diet

Abstract

The aim of this study was to examine the anti-obesity effects of boiled tuna extract in C57BL/6N mice with obesity induced by a high-fat diet (HFD). We determined the anti-obesity effects of boiled tuna extract (100, 200, or 400 mg/kg) on the progression of HFD-induced obesity for 10 weeks. The mice were divided into 5 groups as follows: the normal diet (ND) group (n=10); the HFD group (n=10); the mice fed HFD and 100 mg/kg boiled tuna extract group (n=10); those fed a HFD and 200 mg/kg boiled tuna extract group (n=10); and those fed a HFD and 400 mg/kg boiled tuna extract group (n=10). Changes in body weight, fat content, serum lipid levels and lipogenic enzyme levels were measured. The consumption of boiled tuna extract lowered epididymal tissue weight and exerted anti-obesity effects, as reflected by the serum glucose, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL‑C), low-density lipoprotein cholesterol (LDL-C), insulin and leptin levels. In addition, we demonstrated changes in liver adipogenic- and lipogenic-related protein expression by western blot analysis. Boiled tuna extract downregulated the levels of the CCAAT/enhancer-binding protein α, β and δ (C/EBPα, β, δ), and peroxisome proliferator-activated receptor-γ (PPAR-γ) adipocyte marker genes. Boiled tuna extract also attenuated adipogenic and lipogenic gene expression, namely the levels of fatty acid synthase (FAS), lipoprotein lipase (LPL), acetyl-CoA carboxylase (ACC), glucose transporter type 4 (Glut4) and phosphorylated adenosine monophosphate-activated protein kinase α and β (AMPKα, β) in a dose-dependent manner. Moreover, the consumption of boiled tuna extract restored the levels of superoxide dismutase (SOD), catalase (CAT), glutamic oxaloacetic transaminase (GOT), glutamic-pyruvate transaminase (GPT), aspartate transaminase (AST) and alanine transaminase (ALT) to those of the control group. These results suggest that boiled tuna extract attenuates the progression of obesity by stimulating fatty acid oxidation through the upregulation of AMPK genes, as well as by inhibiting the synthesis of adipogenic and lipogenic enzymes. These characteristics of boiled tuna extract highlight its potential anti-obesity effects.

Muscat Bailey A grape stalk extract ameliorates high-fat diet‑induced obesity by downregulating PPARγ and C/EPBα in mice

“…PPARγ serves a dominant function in the differentiation and maturation of adipocytes (36,37). Previous studies have identified that an HFD induces the expression of adipogenic genes such as those encoding PPARγ and c/EBPα (38)(39)(40). This was also true in the present study as mice fed on an HFD exhibited an increase in the expression of phosphorylated PPARγ and c/EBPα protein.…”

Anti-obesity effects of Diospyros�lotus leaf extract in mice with high-fat diet-induced obesity

“…It serves a role in reducing appetite and increasing energy consumption (30,31). It has been reported that leptin levels in the serum are increased in HFD-induced obese mice (32,33), causing leptin resistance (34). In the present study, it was proven that DLE reduced serum leptin levels in HFD-induced obese mice.…”

Diet Supplementation with Fish-Derived Extracts Suppresses Diabetes and Modulates Intestinal Microbiome in a Murine Model of Diet-Induced Obesity

“…Diet supplementation with fish-derived oil containing omega 3 fatty acids has been shown to possess beneficial effects in diabetes and obesity [ 13 ]. Different types of extracts from fish have been tested for beneficial action on obesity and type 2 diabetes, such as tuna-derived extracts through boiling [ 14 ], Tapra fish-derived fish oil [ 15 ], or ethanol extracts from Masou salmon [ 16 ]. Yet, the contribution of fish extracts on the gut microbiome has not been investigated.…”