You might not be keeping a check on the amount of calories you're consuming during a party, but your brain will, say Yale University researchers, who have identified a molecule that tells brain that the stomach is full - and signals it's time to say no to a second piece of samosa and push back from the dining table.
In a study on rodents, the researchers have discovered that one type of lipid produced in the gut, called N-acylphosphatidylethanolamines or NAPEs, rises after eating fatty foods.
The NAPEs enter the bloodstream and go straight to the brain, where they concentrate in a brain region that controls food intake and energy expenditure.
Led by Gerald I. Shulman, Yale professor of medicine and cellular and molecular physiology and a Howard Hughes Medical Institute investigator, the researchers suggested that the molecule may help regulate how much animals and people eat.
NAPEs are synthesized and secreted into the blood by the small intestine after fatty foods are eaten.
The researchers found that mice and rats injected regularly with NAPEs ate less food and lost weight. In addition, treatment with NAPEs appeared to reduce the activity of "hunger" neurons in the brain while stimulating activity in neurons that are believed to play a role in reducing appetite.
In the last two decades, scientists have made great inroads toward understanding how the body communicates with the brain to control food intake. Till date, hormones such as leptin that act as regulators of this complex system have proved disappointing when tested as potential weight-loss treatments in humans.
The researchers are now planning to investigate how the new findings apply to humans.
The team will first study non-human primates to determine if NAPE concentrations increase in a similar fashion after fat ingestion.
Then, Shulman said: "If chronic NAPE treatment is well tolerated and can cause weight loss by a reduction of food intake, we would have strong impetus to move forward with human NAPE trials."
The findings are published in the latest issue of the journal Cell.