December 7, 2012
Scientists Study Gene That Converts Carbs Into Fat
Connie K. Ho for redOrbit.com — Your Universe Online
Researchers from the University of California, Berkeley (UCB) recently discovered a gene that helps the body change carbs into fat. The team of investigators believes that the finding will be incredibly beneficial in terms of developing treatments for diabetes and fatty liver disease.
In particular, the scientists at UCB looked at how the molecular mechanisms in an individual´s body can turn dietary carbohydrates into fats. Through their research, they came upon BAF60c, a gene that can affect the development of steatosis, otherwise known as fatty liver. Based on the study, the researchers discovered that mice that had the BAF60c gene disabled did not turn carbohydrates into fat while still consuming a diet high in carbohydrates.
"This work brings us one step forward in understanding fatty liver disease resulting from an excessive consumption of carbohydrates," explained the study's senior author, Hei Sook Sul, who serves as a professor in UCB´s Department of Nutritional Science and Toxicology, in a prepared statement. "The discovery of this role of BAF60c may eventually lead to the development of treatment for millions of Americans with fatty liver and other related diseases."
The researchers explained how carbohydrates are broken down into glucose to be used for energy. When there are excess amounts of glucose, it is kept in the liver as glycogen or may be changed into fatty acids by insulin. The fatty acids are then sent to other parts of the body and the adipose tissue stores it as fat. When there are extra amounts of fatty acids, the fat becomes built up in the liver.
"Fatty liver caused by the high intake of carbohydrates can be as bad as that due to excessive alcohol intake, and it contributes to various diseases including type 2 diabetes," noted Sul in the statement. "The conversion of excess glucose into fatty acids occurs in the liver, but there are many steps in this process that have not been fully understood."
The study by Sul and colleagues focused on the role of BAF60c.BAF60c is found in an area outside the nucleus of the cell, otherwise known as the cytoplasm .When insulin binds to a receptor on the surface of the cell, a signal is sent to change BAF60c so that it can move through the nucleus. BAF60c will then bind to parts of the chromatin that have genes coded for different enzymes that can change carbohydrates to fat. Once carbohydrates are turned into fat, more enzymes will be produced to increase the change of carbohydrates to fat.
In the experiment, the researchers were able to examine BAF60c´s ability by heightening and reducing its role in different tests with live mice. They saw that mice who had three times the normal levels of BAF60c in their livers churned out higher levels of fat-producing genes, even during times of fasting. For mice whose BAF60s was disabled, it resulted in the disruption of the production of fatty acids.
"Limiting consumption of sodas, cakes and cookies is a good idea for many reasons, even during the holidays," concluded Sul in the statement.
The study comes at a particularly important time as medical professionals attempt to grapple with the effects of obesity. According to past epidemiological studies, over three-quarters of obese people and one-third of adults in the U.S. suffer from steatosis. A major risk factor is an individual´s diet, and consuming large amounts of bread, pasta, rice, and other forms of carbohydrates can result in an irregular accumulation of fat within a liver cell. As such, the researchers recommend that individuals avoid consuming refined sugars that can up the blood insulin levels. However, complex carbohydrates like those found in fruits, legumes, and vegetables, can be consumed regularly.
The findings of the study were published recently in the journal Molecular Cell.