Australian researchers have shed new light on the role our 'body clock' might play in controlling appetite. Their findings suggest that an individual's obesity level could be determined by a single gene. In other words, the "big boned" excuse just got trumped by something better.
Body clock picture from Shutterstock
Researchers from the Garvan Institute of Medical Research and the University of Sydney uncovered a new cell surface receptor in the brains of mice. The 'Y6' receptor, which is produced in a very small region of the brain, was found to regulate the body clock and growth hormone production.
The research team discovered that when this gene was deleted, mice were smaller and had less lean tissue than their normal counterparts. They also grew noticeably fatter as they aged, especially when fed a high-fat diet, resulting in metabolic problems similar to diabetes
“It is now clear to us that signalling through the Y6 receptor system is critical for the ways in which energy is used at different times of the day,” head researcher Professor Herbert Herzog said in a statement.
“Our work shows that [the gene] is a satiety signal, and probably controls the circadian aspect of food intake -- because the same amount of calories eaten at different times of the day has different effects on body weight.”
The report concludes that Y6 is a critical regulator of energy homeostasis and body composition, with germline deletion of the gene leading to reduced body weight, inhibition of lean body mass and an age-dependent increase in obesity -- in mice at least.
“While it is not clear whether the Y6 receptor is fully active in humans, Pancreatic Polypeptide is highly expressed – even more so than in mice – and it’s possible that another receptor to which the peptide has high affinity, such as Y4, could have taken over this function.”
More research is needed to uncover how closely these findings might relate to the human body clock. In the meantime, you can find plenty of advice on how to maintain a healthy BMI via our Losing Weight, Eating Healthy and Exercise tags.