The human opioid system, which regulates appetite, among other things, could be the target for new anti-obesity drugs, researchers in Finland have discovered.
When faced with external stimuli such as food advertisements or appetizing foods, the opioid system (MOR) is triggered and, in some individuals, could lead to excessive eating, thus potentially causing obesity and the possible consequence of treatment with such drugs, the study in Translational Psychiatry suggested.
“Our study suggests that for individuals with aberrant external eating, (the) MOR system might provide a feasible pharmacological target to combat weight gain,” the study stated.
The researchers at the University of Turku in Finland, working with 92 healthy individuals (70 males and 22 females) using PET scans and eating questionnaires, also investigated the endocannabinoid system, which also regulates bodily functions like sleep, mood and appetite, but found this was less likely to show such a clear correlation.
Low MOR Scores a Factor in Healthy People, Too
While the researchers cited previous PET studies showing opioid release in humans as they eat, as well as other work indicating low MOR associations with binge-eating and morbid obesity, their work was focused on healthy, non-obese subjects.
Even with such individuals, there was a clear distinction between those with low MOR results and others, the former being more likely to be influenced and stimulated by external factors to eat excessively.
“The present findings extend the role of MORs in obesity and eating disorders to different feeding patterns in healthy subjects,” the researchers said.
They also suggested that further studies will be needed to establish a clearer link between low MOR scores and possible excessive eating. Such results could be genetically determined, for example, as opposed to being purely affected by external stimuli.
“It is thus possible that subjects with lower MOR availability are susceptible for increased external eating in (a) modern environment where they are consistently bombarded with feeding cues in advertisements and food shelves in supermarkets,” the researchers noted. “However, the present data are purely cross-sectional, and longitudinal human studies are needed to further disentangle the causes and the effects between the decrease of MORs in relation to external eating.”
With obesity a major health factor, though, such results could be an opportunity for drug makers to help solve the issue, they concluded. “The prevalence of obesity is increasing in alarming speed, and new targets for anti-obesity pharmacotherapy are acutely needed.”