‘Hunger-controlling’ cells discovered in the brain may lead to new way to treat obesity

Treating people for being overweight or obese costs the NHS more than £6bn a year

Certain neurons in the brain have a function in feeding behaviour (Reuters)

Cells in the brain that may help control the hunger impulse have been discovered in a development that could lead to new treatments for obesity.

The research adds weight to the evidence that eating is a surprisingly complex biological behaviour.

“We have identified two new populations of cells in the brain that potently regulate appetite,” said Alexander Nectow, who published a paper about the study in the journal Cell.

The area of the brainstem under scrutiny is the dorsal raphe nucleus (DRN), where the two types of cells are located.

It is thought new drugs to treat obesity by controlling hunger messages that prompt people to seek out and consume of food could be targeted at those cells.

Dr Nectow, an associate research scholar at Princeton University, found that the DRN section of the brain becomes activated in hungry mice. This was discovered when images were taken using a pioneering technique called iDisco.

Imaging other mice that were given more than their normal amount of food showed a different pattern of DRN activity. This showed that neurons in this part of the brain clearly had a function in feeding behaviour.

Further research is needed to ascertain which types of neurons that make up the DRN are involved in the process.

“There are two possibilities when you see something like that,” Dr Nectow said.

“One is that the cells are just along for the ride – they are getting activated by hunger but they’re not actually driving the food intake process.

"The other possibility is that they are in fact part of the sense-and-respond mechanism to hunger – and in this case, we suspect the latter.”

Pioneering research into obesity in the 1990s led to the discovery of the effect of leptin on appetite. It is a hormone which acts on neurons in the hypothalamus area of the brain which suppresses appetite.

An injection of the hormone led to dramatic weight loss in patients with leptin deficiency, but it was also found that there was no effect on many obese people.

"Obesity is generally associated with leptin resistance," said Dr Friedman, whose lab produced the study. "And our recent data suggest that modulation of the activity of specific neurons with drugs could bypass leptin resistance and provide a new means for reducing body weight."

The new research findings could be effective in creating treatments for obesity and its related issues including diabetes. According to Public Health England, treating overweight and obese people costs the NHS more than £6bn a year.

One-fifth of the world’s adults are expected to be obese by 2025, according to a paper published in The Lancet.