Extract of Wax Gourd Peel Prevents High-Fat Diet-Induced Hyperlipidemia in C57BL/6 Mice via the Inhibition of the PPARγ Pathway.

Ming Gu,Xiaobo Ding,Yu Zhang,Cheng Huang,Guang Ji,Gaigai Liu,Yan Lu,Shengjie Fan,Lu Guo

doi:10.1155/2013/342561

Abstract

Wax gourd is a popular vegetable in East Asia. In traditional Chinese medicine, wax gourd peel is used to prevent and treat metabolic diseases such as hyperlipidemia, hyperglycemia, obesity, and cardiovascular disease. However, there is no experimental evidence to support these applications. Here, we examined the effect of the extract of wax gourd peel (EWGP) on metabolic disorders in diet-induced C57BL/6 obese mice. In the preventive experiment, EWGP blocked body weight gain and lowered serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), liver TG and TC contents, and fasting blood glucose in mice fed with a high-fat diet. In the therapeutic study, we induced obesity in the mice and treated with EWGP for two weeks. We found that EWGP treatment reduced serum and liver triglyceride (TG) contents and fasting blood glucose and improved glucose tolerance in the mice. Reporter assay and gene expression analysis showed that EWGP could inhibit peroxisome proliferator-activated receptor γ (PPARγ) transactivities and could decrease mRNA levels of PPARγ and its target genes. We also found that HMG-CoA reductase (HMGCR) was downregulated in the mouse liver by EWGP. Our data suggest that EWGP lowers hyperlipidemia of C57BL/6 mice induced by high-fat diet via the inhibition of PPARγ and HMGCR signaling.

Highlights

Hyperlipidemia is a serious epidemic disease involving lipid metabolism disorder and is a key pathogenic factor resulting in diabetes and cardiovascular diseases [1, 2]
extract of wax gourd peel (EWGP) Prevents Metabolic Disorders Induced in C57Bl/6 Mice by a High-Fat Diet
To test whether EWGP blocks dietinduced body weight gain and dyslipidemia, C57BL/6 mice were fed a high-fat (HF) diet or HF diet mixed with 1%

Summary

Introduction

Hyperlipidemia is a serious epidemic disease involving lipid metabolism disorder and is a key pathogenic factor resulting in diabetes and cardiovascular diseases [1, 2]. Wax gourd is used to treat obesity, hyperglycemia, hyperlipidemia, and as a protection against kidney diseases in China and other East Asian countries [11, 12]. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptor transcription factors and have been identified as drug targets for metabolic disorders. These receptors are lipid and glucose metabolism sensors and are present in adipocytes, liver, and muscle [14]. We show that extract of wax gourd peel (EWGP) may prevent the development of hyperlipidemia and insulin resistance in high-fat diet-fed C57BL/6 mice via inhibition of the transactivities of PPARγ and reduction in the expression of its downstream genes

Materials and Methods

Results

Discussion

Conclusions