Study Shows Hungry Mice Prioritize Social Interaction Over Eating When Brain Stimulated with Leptin
Researchers publishing in the journal Cell Metabolism on Thursday February 23 showed that hungry mice prioritize interacting with members of the opposite sex over eating and drinking when their brains are stimulated with leptin, an appetite-suppressing hormone.
A study published this week in the journal Cell Metabolism used experimental techniques such as optogenetics, chemogenetics, and calcium imaging in freely moving mice to demonstrate that when their brains are stimulated by leptin, moderately hungry mice will choose to interact with the opposite sex instead of attending to their nutritional needs.
When the mice were eating, the neurons expressing leptin receptors in the lateral hypothalamus were suppressed; however, when the mice interacted with members of the opposite sex, these neurons were activated. When the researchers used light and chemical signals to activate the neurons that had leptin receptors, the behavior of the satiated mice was not significantly changed; they still prioritized socializing over eating. However, the same stimulation caused the acutely hungry mice to switch their priorities. When exposed to leptin, mice that were in a state of hunger reacted slower to food, consumed less, and spent more time interacting with potential partners.
While eating, researchers found that the leptin receptor neurons of mice were suppressed; however, when interacting with potential mates of the opposite sex, the neurons were activated, but not when interacting with mice of the same sex.
Korotkova's team conducted an analysis of neurons in the lateral hypothalamus of mice to investigate the brain's prioritizing of instinctual behaviors such as eating, drinking, socializing and mating. This region of the brain is associated with hunger and has receptors for leptin and neurotensin, hormones that convey hunger and thirst signals. To their surprise, the researchers discovered that these neurons not only assist in guiding social behavior, but also aid in balancing nutritional and social needs.
The team compared the behavior of mice with unlimited access to food to those who had been “acutely hungry” (had their food restricted overnight) and “chronically hungry” (whose food had been restricted for 5 days) in order to observe the alteration of priorities based on their level of hunger. The researchers point out that “chronic hunger” can also be seen in nature, where food is not always accessible.
Korotkova stated that this system only has the capability to manage moderate hunger and not intense hunger.
0. “Mice Prioritize Sex Over Food with Leptin's Help” Mirage News, 23 Feb. 2023, https://www.miragenews.com/mice-prioritize-sex-over-food-with-leptins-help-953774
1. “Mice Choose Sex Over Food, Even When Hungry” Technology Networks, 23 Feb. 2023, https://www.technologynetworks.com/proteomics/news/mice-choose-sex-over-food-even-when-hungry-370522
2. “Leptin Helps Hungry Mice Choose Sex Over Food” Neuroscience News, 23 Feb. 2023, https://neurosciencenews.com/leptin-hunger-mating-22556/