Feeling Hungry? Your Brain Might Be On ‘Self-Destruct’ Mode

Scientists have shown how our brain activates self-destruct mechanisms when it is low on energy to regulate appetite.

AsianScientist (Oct. 17, 2016) – Researchers in Korea have uncovered the mechanisms behind the enzyme that controls our appetite in response to low glucose availability in the brain. The findings of the study were published in Autophagy.

Understanding how our appetite is controlled and influenced by our body and brain is important for countering the worldwide obesity epidemic. Previous research has shown that a region of the brain known as the hypothalamus senses levels of sugar (e.g. glucose) and hormones (e.g. leptin) in the blood, and uses these signals to regulate food intake. However, many questions remain about the mechanisms by which the hypothalamus does this.

Professor Kim Eun-Kyoung and her team at Daegu Gyeongbuk Institute of Science and Technology (DGIST) recently discovered that a low glucose condition activates a hypothalamic enzyme called adenosine monophosphate-activated protein kinase (AMPK). This enzyme changes the properties of small protein-like molecules called neuropeptides that our brain uses to communicate, by taking advantage of a natural ‘self-destruct’ mechanism called autophagy. This process allows our body to recycle and degrade cellular materials.

Imagine a movie where the hypothalamus is the director who sets the scene in motion by activating AMPK. Kim discovered how the brain instructs its two key ‘actors’ to do their job: the first actor is a neurohormone called neuropeptide Y (NPY), while the second is another neurohormone produced in the hypothalamus called pro-opiomelanocortin-alpha (POMC). The director activates AMPK, which sets increased autophagy in motion. This in turn influences how our actors, NPY and POMC, behave on a genetic level—similar to a movie that tells a story of increased food intake and body weight.

By demonstrating how AMPK-activated autophagy controls the expression of neurohormones in the brain’s hypothalamus, researchers are one step closer to understanding the dynamics of our eating behavior. The next step is to untangle how autophagy itself influences our brain’s neurohormone levels, such as NPY, to regulate our appetite.


The article can be found at: Oh et al. (2016) Hypothalamic AMPK-induced Autophagy Increases Food Intake by Regulating NPY and POMC Expression.

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Source: Daegu Gyeongbuk Institute of Science and Technology.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

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