New research suggests two brain chemicals involved in the stress response can have very different effects on obesity
Researchers identified two chemical messengers released by the same stress-responsive brain cells that appear to play different roles in weight regulation.
In animal models, changing the release of either messenger affected the development of obesity when the animals ate a high-fat, high-calorie diet.
The findings could help researchers better understand how the brain and stress response are connected to obesity, although more research is needed.
Stress can affect how much we eat and how our bodies regulate weight, but scientists are still working to understand exactly how those processes are connected in the brain.
New research from McGovern Medical School at UTHealth Houston offers a closer look at that relationship. The study focused on a group of brain cells called corticotropin-releasing hormone, or CRH, neurons. These neurons are involved in the body's response to stress through a system known as the hypothalamic-pituitary-adrenal axis.
What makes the findings especially interesting is that these neurons release two different chemical messengers: CRH and glutamate. Researchers wanted to find out whether each one might have a different effect on body weight and the development of obesity.
How did the researchers study it?
The researchers used animal models in which they could increase or decrease the release of CRH or glutamate from adult CRH neurons. This approach was different from some earlier research, which altered CRH or its receptors during embryonic development.
According to the researchers, working with adult neurons helped them avoid potential developmental complications and allowed them to focus more directly on the normal functions of these brain cells in regulating body weight and the stress-response system.
The team then observed what happened when the animals ate either a standard diet or a high-fat, high-calorie diet. They specifically looked at how changing the release of the two chemical messengers affected body weight and the development of diet-induced obesity.
What did they find?
The changes made to the brain cells did not affect body weight when the animals ate a standard diet. The results were different when the animals consumed the high-fat diet.
Reducing glutamate release from CRH neurons or increasing CRH release led to severe diet-induced obesity. On the other hand, reducing CRH or increasing glutamate release did not significantly affect the development of obesity.
The findings also challenged an established understanding of the body's stress-response system. Researchers found that removing CRH or glutamate release caused only mild changes in corticosterone levels, even though CRH has traditionally been considered essential to activity in this system.
For consumers, the research doesn't mean that stress directly causes obesity or that changing these brain chemicals is a treatment. Instead, it offers another piece of the puzzle. The researchers' next step is to identify the neurons that receive glutamate signals from CRH neurons and determine how those pathways contribute to diet-induced obesity.
Posted: 2026-08-31 15:42:47
