Unique Peptide That Can Curb Hunger?

Scientists have identified a unique peptide and hormone that can curb hunger and lessen one's desire for food, potentially leading to future medications that can treat both obesity and binge eating disorders, new research says.

The new peptide/hormone in question is pituitary adenylate cyclase-activating peptide (PACAP). Scientists already know PACAP has an effect on food intake and body weight via the hypothalamus - the area of the brain known for controlling appetite. But this study is the first to show PACAP's effect in the amygdala, a region of the brain outside the hypothalamus, involved in the emotional component of eating.

Using an experimental model, the researchers found that when PACAP is specifically injected to the part of the brain called the "central amygdala," it reduced the intake of food and led to weight loss.

In general, there are two ways of decreasing food intake: either eating less normal-sized meals throughout the day, or eating smaller meals.

"We found that [amygdalar] PACAP reduces the amount of food eaten within meals, but not how many meals are consumed. In addition, we found that PACAP reduced the rate of intake of food. This means that, following administration of PACAP, models were eating more slowly," researcher Valentina Sabino explained in a press release.

However, the researchers note that PACAP alone does not lead to these results; another brain factor has to be at play. The growth hormone called brain-derived neurotrophic factor (BDNF) also has to be involved, otherwise PACAP doesn't exhibit the same effects on food intake and body weight.

"The effects of PACAP on food intake and body weight were absent when it was given together with another drug that blocks BDNF signaling, suggesting that PACAP acts through BDNF," Sabino said.

PACAP could have obvious implications for treating obesity, but due to its impact on not only how much a person eats but also how fast they eat, it can also one day lead to treatments for binge eating - a disease characterized by excessive, uncontrollable eating within a short amount of time.

The results were published in the journal Neuropsychopharmacology.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).