Novel gene identified decreased motivation for food rewards while enhancing exercise motivation, a desirable combination of behaviors, reports a new study. The findings of the study are published in the journal JCI Insight.
The gene, Prkar2a, is highly expressed in the habenula, a tiny brain region involved in responses to pain, stress, anxiety, sleep, and reward. The findings could inform future research to prevent obesity and its accompanying risks for cardiovascular disease and diabetes.
The study was conducted by Edra London, Ph.D., a staff scientist in the section on endocrinology and genetics at NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), and colleagues.
In a previous study, the NICHD team found that despite being fed a high-fat diet, mice lacking functioning copies of Prkar2a were less likely to become obese than wild type mice with normally functioning Prkar2a.
The researchers determined that Prkar2a-negative mice ate less high-fat food than their counterparts, not only when given unlimited access to the food but also after a fast. Similarly, the Prkar2a negative mice also drank less of a sugar solution than the wild type mice. The Prkar2a-negative mice were also more inclined to exercise, running 2-3 times longer than wild type mice on a treadmill. Female Prkar2a-negative mice were less inclined to consume high-fat foods than Prkar2-negative males, while Prkar2-negative males showed less preference for the sugar solution than Prkar2-negative females.