At the conclusion of their study, the rats with suppressed NPYÂ weighed less than the control group.
That’s good news.
The researchers also found that the rats with suppressed levels of NPY exhibited higher levels of spontaneous physical activity, improved blood sugar levels and enhanced insulin sensitivity.
More good news.
But wait, it gets even better.
The researchers then split each of the groups into two, creating four sets of rats.
One of the NPY suppressed groups of rats and one of the control groups were fed a regular diet while the other NPY suppressed and control groups got a high-fat diet.
Of the rats on the regular diet, the control group weighed more at the end of 11 weeks than those rats in which hypothalamic NPY expression was knocked down.
In the high-fat group, the control group rats became obese; those rats in which NPY expression was silenced gained less weight.
And based upon what they already knew about NPY and obesity…this made sense.
Lower levels of NPY = reduced hunger = reduced consumption of food = reduction in body-fat.
What didn’t make sense was the presence of brown fat where they expected to see white fat.
Yep – you read that correctly. Regular old lazy white fat transformed into calorie-burning brown fat.
Lead researcher Sheng Bi said that he believes Â “that the transformation from white to brown fat resulting from NPY suppression may be due to activation of brown fat stem cells contained in white fat tissue”.
How cool is that?
While the current belief is that brown fat cells disappear as we emerge from infancy, this experiment leads us to believe that brown fat stem cells may never disappear and may just become inactive as we age.
So, where do we go from here?
Keeping in mind that this research is at a very early stage and there are lots of reasons why we may not want to lower our NPY levels… it seems to me that the next logical step is for the researchers to find out how to safely & consistently manipulate NPY levels to create another group of Â lab rats with six-packs.
And in another 20 or 30 years, begin testing on humans.