People not to blame for inability to stop eating

A single mutant gene is found to be responsible the brain's inability to tell obese people when to stop eating, a recent research suggests.

Citing a team at Georgetown University Medical Center in Washington DC, News.au.com reported that brain-derived neurotrophic factor (Bdnf) gene in mice stopped or slowed the passage of leptin and insulin signals through the brain

In humans, these hormones are said to be released somewhere around the time when they can see the bottom of the Colonel's 16-piece bucket. It's not guilt telling you to stop, it's your brain saying enough's enough.

If the signals fail to reach the right locations in the area in the brain that signals satiety (the hypothalamus), you plough right on through the popcorn chicken and into the Double-Down.

Happily, it doesn't have to be this way.

"This discovery may open up novel strategies to help the brain control body weight," the study's senior investigator, Baoji Xu, said.

And it's not only weight that the Bdnf gene controls. Prof Xu said that when one particular part of the Bdnf gene fails to develop, it has a flow-on effect that results in deficits in learning and memory.

"If there is a problem with the Bdnf gene, neurons can't talk to each other, and the leptin and insulin signals are ineffective, and appetite is not modified," Xu said.

Now the question is whether the faulty transmission line can be repaired.

One possible strategy would be to produce the missing Bdnf transcript using virus-based gene therapy, Prof Xu says, although it is difficult to deliver across the brain blood barrier.

"The better approach might be to find a drug that can stimulate Bdnf expression in the hypothalamus," Prof Xu says.

"We have opened the door to both new avenues in basic research and clinical therapies, which is very exciting."