Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: cindy goode on 08/05/2010 21:30:02

Title: Can we activate brown fat to reduce obesity?
Post by: cindy goode on 08/05/2010 21:30:02

cindy goode  asked the Naked Scientists:
   
Hello!

I am interested in what you know and think about brown fat found in the human body.  I had never heard of this until recently and from what I understand, the research related to it is relatively new.  What do you think of the possibilities of "activating" this brown fat to fight obesity?
 
Thank you!  Love your show! (http://www.thenakedscientists.com/HTML/podcasts/)
 
Cynthia
Houston, TX

What do you think?

Title: Can we activate brown fat to reduce obesity?
Post by: chris on 12/05/2010 19:14:29

Broadly speaking (and excuse the pun), there are two types of fat in the body: the majority is so-called "white" adipose, which is relatively avascular (lacks blood vessels, hence the whiteness), serves as an energy storage tissue and, being deposited subcutaneously around the entire body, an insulator. The other form of fat is brown adipose, so named because it is highly vascular and also much more metabolically active. This form of tissue is much more restricted in its distribution and is found chiefly between the shoulder blades and around some of the internal organs. It also decreases in abundance with age.

Apart from their corporeal distribution, the chief way in which brown and white adipose differ is that in brown fat the cells burn calories and turn them into heat; in this way they play an important role in maintenance of body temperature and also in maintenance of body weight - because excess calories can be "burned off" and the energy dumped as heat to avoid weight gain.

Brown fat achieves this effect by uncoupling the process of oxidative phosphorylation; this is the final stage in the process of aerobic respiration where electrons fall through a cascade of chemical reactions, surrendering energy at each step to drive the production of the molecule ATP. But in brown fat this electron transport chain, as it's known, is short-circuited so the energy is lost as heat.

This short-circuiting can be stimulated in other tissues by giving drugs that "uncouple" oxidative phosphorylation; charged molecules that can cross the mitochondrial inner membrane - aspirin being one example - can do this. However, past attempts to use this uncoupling phenomenon as a weight-loss strategy have not been successful and there have been serious side effects.

Chris

Title: Can we activate brown fat to reduce obesity?
Post by: kylee on 17/05/2010 10:39:22

I didn't have any idea about those kinds of fats present in our body. Being fat is very frustrating. It is too easy to get big but very difficult to burn fats or loose weight.