Overweight people’s genes respond differently to dietary changes: Study
A specially designed spread with a specific fatty acid composition changed the expression of genes that regulated energy metabolism and inflammation. And the changes were different between overweight and lean people, according to findings published in the journal Genes & Nutrition.
The researchers, led by Marjan van Erk, suggest that the results could lead to the development of better dietary strategies for keeping slightly overweight people healthy for a longer period of time.
"For the first time, we show that a short-term diet change has an effect on the activity of genes that play a role in inflammatory processes in fat tissue of people who are overweight,” said Henk Hendriks, a senior scientist in human physiology at TNO and co-researcher in the study.
“The technique is an example of nutrigenomics research, and it allows us to investigate the effect of complex mixtures of functional food ingredients on fat tissue. The first findings show that genes in fat tissue are sensitive to diet changes. The result also strengthens our hypothesis that fat tissue is actively involved in the development of obesity-related disease,” added Hendriks.
Nutrigenomics is defined as how food and ingested nutrients influence the genome (personalised nutrition). Nutrigenetics is defined as how a person's genetic make-up affects a response to diet (individual nutrition).
Study details
The researchers recruited 10 lean and 10 overweight men and assigned them to consume a specially-designed spread and a control spread for nine days. Both spreads contained the same amount of fat, but the fat composition was different. The special spread contained higher levels of medium chain triglycerides, short-chain polyunsaturated fatty acids (C18:2 and C18:3) and conjugated linoleic acid (CLA: C18:2).
Subcutaneous fat tissue biopsies taken from the volunteers showed that the activity of the genes differed significantly between lean and overweight men. They found that the special spread was associated with a higher expression of genes related to energy metabolism. It was also linked to a lower activity of inflammatory genes and higher activity of genes related to lipid metabolism.
Such changes would undoubtedly lead to health improvements, as up-regulation of the energy metabolism genes may decrease fat tissue mass. On the other hand, reductions of the inflammatory processes has potential benefits since chronic inflammation has been linked to range of conditions linked to heart disease, osteoporosis, cognitive decline and Alzheimer's, type-2 diabetes, and arthritis.
Implications
“Some studies report a role for subcutaneous abdominal tissue in obesity related diseases,” wrote the researchers.
“The finding that subcutaneous adipose tissue responds to nutritional intervention is encouraging for further research, as this is the only easily accessible source of adipose tissue from humans. Thus, whole genome expression profiling in adipose tissue may help to identify relevant mechanisms and targets of nutritional intervention in obesity prevention or treatment,” they said.
Source: Genes & NutritionDecember 2008, Volume 3, Numbers 3-4, Pages 127-137, doi 10.1007/s12263-008-0096-z“Short-term fatty acid intervention elicits differential gene expression responses in adipose tissue from lean and overweight men”Authors: M.J. van Erk, W.J. Pasman, H.M. Wortelboer, B. van Ommen, H.F.J. Hendriks
The article is available via: http://www.springerlink.com/content/h05p2250145528n5/fulltext.html
