Worms Get the Munchies Too Says New Study

Liz Filmer
24 Apr 2023

A recent study found that when under the influence of THC, "roundworms" or "Caenorhabditis elegans" to use their official names,  feed for longer than usual and vehemently prefer high-quality foods over less nutritious options.

 The study, published this year, suggests that the way in which cannabis influences appetite developed more than 500 million years ago. This commonality suggests that C. elegans could be utilized to investigate how cannabis impacts our nervous system.

 "The more we know at a basic level about drug physiology, the more healthy our society will ultimately be", Shawn Lockery, neuroscientist, University of Oregon.

Cannabinoid molecules bind to the same receptors as molecules naturally found in the body, called endocannabinoids. Those receptors are found in the brain and many other tissues. The endocannabinoid system, as it is known, is believed to control critical functions like sleep, eating, memory, and anxiety.

The experiment involved putting C. elegans in a T-shaped maze holding two food options and monitoring which the worms choose to approach. The researchers submerged the worms in a solution of the endocannabinoid anandamide before they were placed in the maze.

When in receipt of endocannabinoids, the worms developed an enormous appetite and preferred nutritionally superior bacteria. They spent more time eating than the "sober" worms. 

 In following experiments, the researchers tested endocannabinoids on worms genetically modified to have human cannabinoid receptors and noted that the modified worms responded similarly. 

Additionally, the investigators identified the effect of cannabinoids on one of the principal food-detecting olfactory neurons, which, in the worms that were given the drug, became more susceptible to the smells of favoured food and less sensitive to the smells of rotten food.

Prior research shows cannabinoids cause a 'hedonic feeding' in mammals other than humans, including rodents and primates. In addition, C. elegans have now been added to the list, suggesting that cannabinoid receptors and cannabinoid-influenced conducts evolved long ago.

The similarities between mammals and C. elegans may prove a cost-effective way to explore how cannabis-derived compounds affect the nervous system in humans.

 Cannabis research will continue to develop as the plant becomes legal in more regions. Studying these compounds used to be very difficult; however, so much more will be discovered in this area over the next five to ten years as researchers gain an increasing understanding of how these compounds work. 

Liz Filmer