Scientists from two groups, including the University of Cambridge and the Children’s Hospital in Los Angeles, have found out how genes responsible for the development of the nervous system affect body weight. They also found that brain cells have a memory and adjust a person’s eating habits after each meal.

Scientists have identified a set of molecules that link the brain’s body weight center and genes that control brain development, especially in the hypothalamus, which plays an important role in regulating food intake and blood sugar levels. The lab investigated the formation of connections between brain cells and studied a group of molecules called semaphorins that direct cells along a particular path.

Blocking semaphorin signaling in hypothalamic cells led to the suspension of brain cell growth and an increase in body weight. Understanding these processes will help fight the problem of obesity in children and adults.

A recent study confirms that semaphorins play a key role in regulating calorie intake and body weight. By examining the genetic information of 1,000 obese people, the scientists found that gene changes associated with semaphorin signaling are less common in people with early obesity. This demonstrates the importance of semaphorins in maintaining a healthy body weight.

Dr. Agatha van der Klaue, who led the study, said genes associated with semaphorin signaling form circuits in the hypothalamus that regulate appetite and metabolism. The results of the study show that semaphorins shape the physical structure of the brain and affect the circuitry that regulates body weight.



The brain cells that control memory play an important role in our eating behavior, a new study from Georgia State University shows. They found that neurons in the hippocampus can control our eating habits, storing memories of our last meal and causing a feeling of fullness that lasts longer than the hormonal reflexes triggered by eating.

Using an optogenetics technique to block hippocampal cells in rats led them to eat more and before their next meal. The effect was independent of what the rats were offered to eat. The scientists concluded that the blockage of hippocampal cells affects the consolidation of memory and causes a desire to eat in the future.

The findings could help fight obesity if scientists find a way to use knowledge about how to control nutrition with the brain.