FGF21 hormone drives protein-specific appetite and reward in the brain

If they are confronted with multiple food options and ultimately choose one, the factors of that decision -making process can be more physiological than previously assumed. A group of scientists led by Pennington Biomedical Research Center’s Dr. Christopher Morrison recently discovered that the hormone fibroblast growth factor 21, or FGF21, plays an influential role in brain relief mechanisms as involved in food choices.

The discovery was announced in the recent article of the research team entitled “FGF21 Acts in the Brain to stimulate macronutrient-specific changes in behavioral motivation and brain sensation signaling”, which was published in the January 2025 number of the magazine Molecular metabolism. The study data indicate that the FGF21 hormone works on the brain to induce a protein-specific appetite by improving the reward value of foods containing protein.

What is fascinating is that this is not only general hunger – it is a very specific appetite for proteins. When protein is limited, FGF21 works in the brain to turn a molecular switch that makes protein -rich food more rewarding and motivates animals to look for them. Many people struggle to maintain a balanced diet. Insight into how the body naturally regulates protein appetite can lead to better strategies for promoting healthy eating. ”

Dr. Christopher Morrison, associated executive director of Basic Science at Pennington Biomedical

In the study, animals worked on a low protein diet especially hard for liquid protein rewards, but not for carbohydrates, fat or sweet rewards, compared to that on a normal diet. However, if the ability of FGF21 to act in the brain was disturbed, this protein -specific motivation was lost.

The researchers then used an advanced neuroscientific technique called fiberotometry to assess how nutrients dopamine -neurons activate in the ventral tile area, or VTA, a brain area associated with reward. They discovered that protein restriction is shifting the dopamine response, with carbohydrate dopamine neurons in control animals and proteins more strongly activate dopamine neurons in protein-restricted animals. It is important that this shift in reward signaling was lost in animals that miss FGF21.

“It is a remarkable example of how hormone signals can coordinate the brain’s reward system to stimulate specific nutritional appetite,” says Dr. Morrison out.

“This recent discovery shows the continuous journey to discover the functions of certain genes, proteins and nutrients in our body, while the most important value also emphasizes that Pensnington Biomedical delivers to the broader scientific community,” Dr. John Kirwan, executive director of Pennington Biomedical. “Insight into how the brain stimulates specific nutritional preferences has been a long -term challenge in research of metabolism. This work is an example of how the integrative approach to Pennington Biomedical – combining molecular biology, neurosciences and behavioral studies – can unlock complex biological mysteries. His team for this extensive study, and I look forward to the additional discoveries that will arise because of these. ”

The FGF21 hormone is produced in the liver and is rather recognized as a regulator of energy balance and because of its role in glucose metabolism. This newly published research emphasizes its significant impact on the central nervous system.

This study was supported by subsidies from the National Institutes of Health and reflects the dedication of Pennington Biomedical to promote the understanding of biological mechanisms that underlie food and metabolism.