In a recent study conducted at University College London, researchers have delved into the intricate relationship between gut-produced hunger hormones and decision-making processes in mice. Published in the journal Neuron, the findings illuminate the ability of hunger hormones, such as ghrelin, to breach the blood-brain barrier, exerting a direct influence on brain activity and behavior. This discovery suggests potential parallels in humans, offering a deeper understanding of how hunger shapes decision-making.
The blood-brain barrier is a critical physiological barrier that typically restricts the passage of substances from the bloodstream to the brain. Despite its strict regulation, the study observed that hunger hormones can traverse this barrier, impacting brain activity and behavior.
To explore the connection between hunger hormones and behavior, researchers designed experiments involving mice placed in an arena with food. Interestingly, while all mice investigated the food, only those in a hungry state exhibited actual eating behavior. This prompted a closer examination of neural activity in the ventral hippocampus, a brain region associated with decision-making and memory formation.
The study unveiled that specific brain cells in the ventral hippocampus demonstrated increased activity when mice approached food. Intriguingly, this heightened neural activity inhibited the mice from eating. However, in a hungry state, a decrease in neural activity in this region was observed, removing the inhibition and prompting the mice to eat. This change corresponded with elevated levels of the hunger hormone ghrelin circulating in the blood.
In a noteworthy experimental manipulation, researchers activated ventral hippocampal neurons, inducing a state in which mice behaved as if they were full, resulting in a cessation of eating. This manipulation underscores the direct link between neural activity and feeding behavior.
The implications of these findings extend beyond the realm of basic physiology. Researchers believe that this study could significantly contribute to understanding the mechanisms underlying eating disorders. Furthermore, the research hints at potential connections between diet and mental health outcomes, providing a foundation for exploring broader implications.
As the study’s authors continue their research, they aim to investigate the impact of hunger on learning and memory. This includes exploring whether hungry mice perform non-food-specific tasks differently, shedding light on the cognitive effects of hunger. Additionally, the researchers express interest in examining whether similar neural mechanisms come into play in response to stress or thirst.
