Weight loss with the flick of a switch

Imagine a world where programs such as Jenny Craig, Weight Watchers and Tony Ferguson are extinct as a result of one molecular switch. For researchers at Dana-Farber, this vision is becoming a reality, with the discovery of a two part molecular switch that causes cells to develop into brown fat. This particular brown adipose tissue is energy burning, thus having the ability to counteract obesity and possibly serve as a treatment for both heart disease and diabetes.

The research team, led by Bruce Spiegelman have discovered a protein, PRDM16 that acts as a switch which determines whether immature muscle cells develop into mature muscle or brown adipose cells. Furthermore, the researchers have discovered a second protein, which works in tandem with PRDM16 called C/EBP-beta. This particular protein initiates brown fat development. To determine whether cells could be manipulated, Spieglman and his team transferred the switch through a virus into connective tissue cells of adult mouse skin called fibroblasts. Astonishingly, tests detected that brown adipose tissues were burning excess caloric energy at high rates. The phenomenal ability of the brown fat to burn energy is a result of high amounts of mitochondria in the cells. Normally, this excess energy would’ve been stored in white adipose tissue which contains comparatively few mitochondria.

The idea of a molecular switch as a weight loss treatment is simply remarkable. However, at present, the only method of administration would be via a transplant. That is, tissues are removed from a patient; the molecular switch is added and is returned to the body. According to spiegelman, “a more conventional possibility would be to administer a drug to the patient that would ramp up the production of brown fat without the need for a transplant”. Thus, one challenge remains for the team, to find a hormone that can accomplish this. If achieved, the drug would be a one of a kind, direct obesity treatment with profound implications for society.


Kathleen Smith
Reference:
Dana-Farber Cancer Institute (2009), ‘Scientists Create Energy-burning Brown Fat In Mice’, ScienceDaily, viewed August 10th 2009, available from: http://www.sciencedaily.com/releases/2009/07/090729132109.htm