Scientists from Monell Centre and Kyushu University in Japan have found that controling feeding behaviour may assist in battling obesity and associated diseases.
They found that endocannabinoids, substances similar to THC, the active ingredient in marijuana, act directly on taste receptors on the tongue to enhance sweet taste.
"Our taste cells may be more involved in regulating our appetites than we had previously known," said study author Robert Margolskee, M.D., Ph.D., a Monell molecular biologist.
"Better understanding of the driving forces for eating and overeating could lead to interventions to stem the burgeoning rise in obesity and related diseases," he added.hey are produced in the brain and body, and bind with cannabinoid receptors to help regulate appetite and many other processes involved in health and disease.
"Endocannabinoids both act in the brain to increase appetite and also modulate taste receptors on the tongue to increase the response to sweets," said study senior author Dr Yuzo Ninomiya, Professor of Oral Neuroscience in the Graduate School of Dental Sciences at Kyushu University in Japan.
During the study, researchers conducted a series of experiments in mice to determine the behavioural, neural and cellular responses to sweet taste stimuli before and after the administration of endocannabinoids.
Sweet taste responses were enhanced by endocannabinoids in every case. The effect was specific for sweet taste, as endocannibinoids had no effect on responses to sour, salty, bitter or umami taste stimuli.
However, the effects were abolished when the experiments were repeated using knockout mice lacking the CB1 cannabinoid receptor.
"Modulation of sweet taste responses may be an important component of the endocannabinoid system's role in regulating feeding behaviour," said Margolskee.
The study is published online in the Proceedings of the National Academy of Sciences.