Metabolic effects of whole grain wheat and whole grain rye in the C57BL/6J mouse

Received 3 September 2008; accepted 9 June 2009. published online 03 August 2009.

Abstract

Objective

A diet rich in whole grain cereals is suggested to protect against type 2 diabetes and facilitate body weight regulation. However, little is known about the impact of different cereals and the underlying mechanisms. The objective of this study was to compare the long-term metabolic effects of diets supplemented with whole grain wheat or whole grain rye in the C57BL/6J mouse.

Methods

Mice were fed the whole grain supplements in a low-fat background diet for 22 wk. Oral and intravenous glucose tolerance tests were performed during the study and in vitro insulin secretion assays were performed at the end of the study. Body weight, energy intake, body fat content, and plasma parameters were measured during the study.

Results

A dietary supplement of whole grain rye suppressed body weight gain and resulted in significantly decreased adiposity, plasma leptin, total plasma cholesterol, and triacylglycerols compared with a supplement of whole grain wheat. Also, a slight improvement in insulin sensitivity was observed in the rye group compared with the wheat group. The decreases in body weight and adiposity were observed in the absence of differences in energy intake.

Conclusion

Long-term administration of whole grain rye evokes a different metabolic profile compared with whole grain wheat in the C57BL/6J mouse, the primary difference being that whole grain rye reduces body weight and adiposity compared with whole grain wheat. In addition, whole grain rye slightly improves insulin sensitivity and lowers total plasma cholesterol.

Keywords: Whole grain wheat, Whole grain rye, Obesity, Glucose tolerance, Cholesterol

Abbreviations: LFD, low fat diet, MFD, medium fat diet, OGTT, oral glucose tolerance test, IVGTT, intravenous glucose tolerance test, DEXA, dual-energy X-ray absorptiometry, TAG, triacylglycerols, WAT, white adipose tissue, NEFA, non-esterified fatty acid

a Department of Experimental Medical Science, Division of Diabetes, Metabolism and Endocrinology, Lund University, BMC, Lund, Sweden

b Department of Food Technology, Engineering and Nutrition, Division of Applied Nutrition and Food Chemistry, Lund University, Lund, Sweden

Corresponding author. Tel.: +46-46-2228128; fax: +46-46-2224022.

Financial support was provided by the FuncFood Ph.D. program at Lund University, the Swedish Research Council (project 11284 to C.H., project 4499 to N.W.), the Swedish Diabetes Association, Dir. Albert Påhlsson's Foundation, The Royal Physiographic Society in Lund, the Novo Nordisk Foundation, and the Torsten and Ragnar Söderberg Foundation.

PII: S0899-9007(09)00253-6

doi:10.1016/j.nut.2009.06.007

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