Effects of dietary carbohydrate replaced with wild rice (Zizania latifolia (Griseb) Turcz) on insulin resistance in rats fed with a high-fat/cholesterol diet.

Shufen Han,Hong Zhang,Chengkai Zhai,Liqiang Qin

doi:10.3390/nu5020552

Abstract

Wild rice (WR) is a very nutritious grain that has been used to treat diabetes in Chinese medicinal practice. City diet (CD) is based on the diet consumed by Asian area residents in modern society, which is rich in saturated fats, cholesterol and carbohydrates. The present study was aimed at evaluating the effects of replacing white rice and processed wheat starch of CD with WR as the chief source of dietary carbohydrates on insulin resistance in rats fed with a high-fat/cholesterol diet. Except the rats of the low-fat (LF) diet group, the rats of the other three groups, including to high-fat/cholesterol (HFC) diet, CD and WR diet, were fed with high-fat/cholesterol diets for eight weeks. The rats fed with CD exhibited higher weight gain and lower insulin sensitivity compared to the rats consuming a HFC diet. However, WR suppressed high-fat/cholesterol diet-induced insulin resistance. WR decreased liver homogenate triglyceride and free fatty acids levels, raised serum adiponectin concentration and reduced serum lipocalin-2 and visfatin concentrations. In addition, the WR diet potently augmented the relative expressions of adiponectin receptor 2, peroxisome proliferator-activated receptors, alpha and gamma, and abated relative expressions of leptin and lipocalin-2 in the tissues of interest. These findings indicate that WR is effective in ameliorating abnormal glucose metabolism and insulin resistance in rats, even when the diet consumed is high in fat and cholesterol.

Highlights

IntroductionThe intake of food rich in saturated fats, cholesterol and refined carbohydrate, which is the diet composition of Asian area residents, is pervasive and, results in the prevalence of nutrition-related chronic metabolic diseases in China, Japan and other developing countries [1,2]
The intake of food rich in saturated fats, cholesterol and refined carbohydrate, which is the diet composition of Asian area residents, is pervasive and, results in the prevalence of nutrition-related chronic metabolic diseases in China, Japan and other developing countries [1,2].Insulin resistance has been shown to be the major contributing factor to these metabolic diseases [3,4].In addition, the dietary carbohydrate source of this diet, based on the composition of Asian area residents, is mainly from white rice and processed wheat starch, and many of the health-promoting components of intact whole-grain cereals were lost upon refining
After eight weeks of diet feeding, the rats fed with the Wild rice (WR) diet had significantly lower weight gain than the rats fed with the City diet (CD)

Summary

Introduction

The intake of food rich in saturated fats, cholesterol and refined carbohydrate, which is the diet composition of Asian area residents, is pervasive and, results in the prevalence of nutrition-related chronic metabolic diseases in China, Japan and other developing countries [1,2]. The dietary carbohydrate source of this diet, based on the composition of Asian area residents, is mainly from white rice and processed wheat starch, and many of the health-promoting components of intact whole-grain cereals were lost upon refining. The main approach used for exploring the physiological functions and recognized health benefits of whole-grain cereals has been focused on investigating each isolated compound. It is agreed to advance that this is the synergistic action of many bioactive compounds occurring in intact whole-grain cereals [8,9]

Results

Discussion

Conclusion