Brown fat, burns energy rather than storing it, which the more common white fat does. The study, published in the October issue of Endocrinology, sought to learn more about how to get brown fat cells to grow. It identified two molecular pathways that lead to a protein called necdin that blocks brown fat growth.
With this information, researchers can look for ways to modify the steps along the pathways, either to stimulate another protein, called CREB, which shuts down necdin, or block a different protein called FoxO1, located along the second pathway, which stimulates necdin. The study showed for the first time that the two proteins can bind directly to the necdin gene.
One pathway to necdin starts with insulin cells and runs through proteins called Ras and ERK1/2 before getting to CREB. The second also starts with insulin and runs through proteins called P13-K and Akt before getting to FoxO1.
This is the latest in a series of studies on brown fat led by Drs. Cypess and Tseng. In July, Dr. Cypess and his team showed that brown fat can be seen on imaging studies in nearly half of all children and is most active in those who are thin. The amount of the fat also increases in children up until puberty, when it begins to decline, according to that study, published in the Journal of Pediatrics.
In 2009, Dr. Cypess and his team demonstrated in the New England Journal of Medicine for the first time that brown fat is metabolically active in adult humans. Previously, it had been thought that brown fat was present only in babies and children. The 2009 study showed it was found to be active under normal living conditions in 5.4 percent of all adults, with higher rates in women.
Source: http://www.sciencedaily.com/releases/2011/09/110921075423.htm
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