Friday, December 13, 2013
Regular readers are well aware of the myriad of complex sociopsychobiological factors that control food intake.
Not least amongst these is stress – I am sure many readers will attest to the impact that stress can have on their appetite (both positive and negative).
Now, a paper by Zul Merali and colleagues from the University of Ottawa, published in Frontiers in Neuroscience, discusses the potential role of bombesin-like peptides (for my nerdier readers: bombesin, is a 14 amino acid peptide first isolated from the skin of the frog Bombina bombina) in linking stress to ingestive behaviour.
As the authors note,
“In humans, stress causes increased food intake in one subset of the population and conversely causes decreased food intake in another; why some people lose weight and other gain weight is not yet well understood.“
The paper discusses the dual effects of the bombesin family of peptides in regulating food intake as well as mediating stress response, which interact at the level of reward pathways.
Evidence from animal studies suggests that bombesin-like peptides, under certain conditions are involved in stress-induces anorexia, while the same pathways, under other conditions, can lead to stress-induced overeating.
Much of this has to do with the unique distribution of bombesin-like peptides in key cortico-limbic brain regions involved in food regulation, reward, incentive salience and motivationally driven behavior.
The hope is that better understanding the functioning of this system may teach us much about how stress affects eating behaviour and may help identify pharmacological targets that can be harnessed to affect both.
Merali Z, Graitson S, Mackay JC, & Kent P (2013). Stress and eating: a dual role for bombesin-like peptides. Frontiers in neuroscience, 7 PMID: 24298233