Brown fat: The thing that could help treat obesity?

JAIPUR: Did you know that there are “brown fat cells” in the body that do just the opposite of what most fat cells? Most fat cells store energy in the human body – the

brown fat

cells burn energy to generate heat. Researchers at

Salk Institute for Biological Studies

in

California

have now discovered that the molecule ERR? gives ‘healthier’ brown fat the energy-expending identity.


These are the cells that help one warm up when stepping out in the cold. And these are the cells scientists say could aid in preventing obesity. The Salk research was published in the scientific journal Cell Reports on March 13.

A report of the findings on website Science Daily quoted senior author

Ronald Evans

: “This not only advances our understanding of how the body responds to cold, but could lead to new ways to control the amount of brown fat in the body, which has links to obesity, diabetes and fatty liver disease.”

Science Daily reports that about a decade ago, the scientific community held that only babies -- who can’t yet shiver to warm up - had brown fat in their bodies. It is now known that adults too have brown fat but at much lower levels. People with lower body mass indexes (BMIs) tend to have more.

Researchers found that brown fat cells are full of energy-generating mitochondria. This is what gives them the brown colour. Evans’ group focused on estrogen-related receptor gamma (ERR?), a gene found to be active at high levels in these cells.

The team found that the brown fat cells express the ERR? gene all the time, and not just when the body is exposed to cold. White fat cells do not express the gene at all. By studying mice that lack the gene for ERR? (and therefore unable to make the ERRy molecule), the team observed that all brown fat cells resembled white cells in these mice. Animals that lacked this gene also were unable to maintain body temperature when exposed to cold.

The researchers are planning to also look, in future research, at the effect of activating ERR? in white fat cells. They expect that this could make some white fat cells resemble the brown fat, and potentially treat conditions like obesity and diabetes. They will also explore whether the role of ERR? in brown fat of humans is the same as what is observed in mice.