Now scientists have used the experimental drug Roscovitine in mice to produce patches of brown fat within white to improve metabolism. They also developed a novel way to sort brown fat cells from white and sequence the cells’ genes.
Their work uncovered three genetically distinct forms of brown fat, which they are calling “classic brown,” “beige,” and “brite,” all of which seem to arise from different pathways. The work is significant because it suggests multiple routes and methods through which brown fat might be encouraged to grow.
Brown fat burns glucose and lipids to create heat, and it works in other ways to counter obesity, inflammation, and their ill effects. For many years, scientists thought that brown fat existed only in small mammals and newborn human babies, who need help staying warm. Then, in 2009, scientists found brown fat in adult humans.
Scientists have since found several ways to coax the growth of brown or “brown-like” fat in mice. The burning questions today: What is the best way to encourage the growth of brown fat or, even better, turn bad white fat into brown? And is there a way to turn this basic science into a drug for humans? If so, it would be the biological equivalent of turning lead to gold.