Brain reveals the risk for developing obesity

by University of Turku

Impact of obesity risk factors on brain function. a) Family-related risk factors (parents’ obesity and diabetes) were associated with altered insulin signalling in the subject’s widespread brain regions. More yellow colour signifies stronger association. b) Family-related risk factors were associated with decreased opioid receptor availability in regions related to producing pleasure in the subject’s brain. Lighter blue colour signifies stronger association. Credit: International Journal of Obesity

Obesity risk factors of family background are associated with changes in the brain function, finds a study conducted at the Finnish Turku PET Centre. The results show that the function of neural networks regulating satiety and appetite is altered already before a person develops obesity.

Obesity is a globally increasing health problem, and new interventions to prevent and treat obesity are needed. Obesity is linked to changes in brain insulin sensitivity and neurotransmitter function. These changes may explain increased appetite and overeating.

“However, thus far it has not been determined whether these changes are visible in the brain already before a person develops obesity, and if these changes would increase the risk for future obesity,” says Doctoral Candidate Tatu Kantonen from the Department of Clinical Medicine of the University of Turku.

Kantonen’s study investigated changes in the brain in pre-obesity by studying the insulin, opioid, and cannabinoid function through PET imaging. The participants of the study consisted of 41 young men with varying number of obesity risk factors.

The results showed that family-related risk factors such as parents’ obesity or diabetes were associated with altered insulin signaling in the subject’s brain as well as reduced function of the opioid and cannabioid systems.

“Disturbance in the neural networks controlling satiation and appetite can therefore be observed already before a person develops obesity, and these brain changes are connected to family-related risk factors of obesity. The results may have implications for the development of prevention and treatment interventions for obesity. They show that the brain and central nervous system are important targets in the treatment of obesity,” says Kantonen.

The research article, “Obesity risk is associated with altered cerebral glucose metabolism and decreased μ-opioid and CB1 receptor availability,” has been published in the International Journal of Obesity.