The Unexpected Brain Benefits of an Anti-Obesity Drug

Researchers on the Max Planck Institute discovered that weight problems, characterised by decreased insulin sensitivity, impairs the mind’s associative studying functionality. However, a single dose of the anti-obesity drug liraglutide restored this capacity, equalizing mind exercise between overweight and normal-weight contributors.
Liraglutide enhances mind perform in people with weight problems.
For our mind to manage our actions, it wants to determine hyperlinks between totally different stimuli. For occasion, it learns to attach a seemingly innocent visible cue to its potential final result (like a red-hot hotplate indicating a danger of burning one’s hand). This course of helps our mind perceive the results of interacting with sure stimuli.
Associative studying is the idea for forming neural connections and provides stimuli their motivational power. It is actually managed by a mind area known as the dopaminergic midbrain. This area has many receptors for the body’s signaling molecules, comparable to insulin, and may thus adapt our habits to the physiological wants of our body.
But what occurs when the body’s insulin sensitivity is decreased attributable to weight problems? Does this alteration our mind exercise, our capacity to be taught associations, and thus our habits? Researchers on the Max Planck Institute for Metabolism Research have now measured how nicely the training of associations works in contributors with regular body weight (high insulin sensitivity, 30 volunteers) and in contributors with weight problems (decreased insulin sensitivity, 24 volunteers), and if this studying course of is influenced by the anti-obesity drug liraglutide.
Low insulin sensitivity reduces the mind’s capacity to affiliate sensory stimuli.
In the night, they injected the contributors with both the drug liraglutide or a placebo within the night. Liraglutide is a so-called GLP-1 agonist, which prompts the GLP-1 receptor within the body, stimulating insulin manufacturing and producing a sense of satiety. It is commonly used to deal with weight problems and sort 2 diabetes and is given as soon as a day.
The subsequent morning, the themes got a studying process that allowed the researchers to measure how nicely associative studying works. They discovered that the power to affiliate sensory stimuli was much less pronounced in contributors with weight problems than in these of regular weight and that mind exercise was decreased within the areas encoding this studying habits.
After only one dose of liraglutide, contributors with weight problems now not confirmed these impairments, and no distinction in mind exercise was seen between contributors with regular weight and weight problems. In different phrases, the drug returned the mind exercise to the state of normal-weight topics.
“These findings are of fundamental importance. We show here that basic behaviors such as associative learning depend not only on external environmental conditions but also on the body’s metabolic state. So, whether someone is overweight or not also determines how the brain learns to associate sensory signals and what motivation is generated. The normalization we achieved with the drug in subjects with obesity, therefore, fits with studies showing that these drugs restore a normal feeling of satiety, causing people to eat less and therefore lose weight,” says research chief Marc Tittgemeyer from the Max Planck Institute for Metabolism Research.
“While it is encouraging that available drugs have a positive effect on brain activity in obesity, it is alarming that changes in brain performance occur even in young people with obesity without other medical conditions. Obesity prevention should play a much greater role in our healthcare system in the future. Lifelong medication is the less preferred option in comparison to primary prevention of obesity and associated complications,” says Ruth Hanßen, first writer of the research and a doctor on the University Hospital of Cologne.
Reference: “Liraglutide restores impaired associative learning in individuals with obesity” by Ruth Hanssen, Lionel Rigoux, Bojana Kuzmanovic, Sandra Iglesias, Alina C. Kretschmer, Marc Schlamann, Kerstin Albus, Sharmili Edwin Thanarajah, Tamara Sitnikow, Corina Melzer, Oliver A. Cornely, Jens C. Brüning and Marc Tittgemeyer, 17 August 2023, Nature Metabolism.
DOI: 10.1038/s42255-023-00859-y
The research was carried out on the Max Planck Institute for Metabolism Research and supported by the CECAD Cluster of Excellence for Ageing Research on the University of Cologne and the University Hospital of Cologne.