Brain's Reward Pathway Changed With Liver Hormone
Researchers at UT Southwestern Medical Center have found a liver hormone that helps reduce cravings for sweets and alcohol through the brain's reward pathway, according to a new study.
The hormone, known as fibroblast growth factor 21 or FGF21, is linked to environmental stress, including extreme dietary changes or cold temperature exposure and is produced when mammals consume carbohydrates. Research has also shown that the hormone's unique effects could be effective in treating obesity and type 2 diabetes.
"Our findings raise the possibility that FGF21 administration could affect nutrient preference and other reward behaviors in humans, and that the hormone could potentially be used to treat alcoholism," said Dr. Kliewer, who holds the Nancy B. and Jake L. Hamon Distinguished Chair in Basic Cancer Research, in a news release.
During the study, researchers found that mice with elevated levels of FGF21 showed a reduced preference for sweetener- and alcohol-laced water that's marked to decrease dopamine levels--a neurotransmitter that's important in reward behavior.
To confirm that FGF21 acts via a brain pathway, the researchers took advantage of the fact that FGF21 requires the co-receptor β-Klotho in order to function. When FGF21 levels were increased in mice genetically unable to make β-Klotho in the central nervous system, the effect on taste preference disappeared.
"The finding that FGF21 acts via the brain was completely unexpected when we started down this path of investigation a dozen years ago," Dr. Kliewer said. "These findings suggest that additional studies are warranted to assess the effects of FGF21 on sweet and alcohol preference and other reward behavior in humans."
The study is published in the journal Cell Metabolism.
For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).