Cannabinoid-infused worms have a stronger-than-usual preference for high-calorie foods
Researchers in Oregon have studied a small worm of one millimeter: Caenorhabditis elegans by genetic engineering. Cannabinoids have been shown to increase overt expressions of pleasure during feeding, and researchers have determined that worms, like humans, become hungry and develop cravings for snacking when exposed to cannabis.
Humans aren't the only ones with food cravings: Worms also show the same urge to munch on their favorite food after consuming cannabis, according to a researcher. new study. The researchers succeeded in simulating getting high in worms by soaking them with cannabinoids.
It's unclear whether the worms got high, but they showed a stronger preference for high-calorie foods, much like humans crave junk food after consuming cannabis. This finding suggests that cannabis may interfere with an important mechanism that helps regulate appetite, the study concludes.
Cannabinoids are known to work by binding to proteins in the brain, nervous system, and other parts of the body called cannabinoid receptors. If cannabinoids contain a chemical known as THC, they can induce feelings of relaxation and satisfaction.
Normally, these receptors respond to naturally occurring cannabinoids in the body, called endocannabinoids. The endocannabinoid system plays an important role in nutrition, anxiety, learning and memory, reproduction, and metabolism.
Shawn Lockery, one of the study authors and professor of biology and neuroscience at the University of Oregon in the United States, said: “Cannabinoid signaling is present in the majority of tissues in our body. It could therefore be implicated in the cause and treatment of a wide range of diseases”.
For the study, the scientists soaked the worms anandamide, an endocannabinoid. Worms are thought to find high-calorie foods more desirable and actively seek them out. When soaked in anandamide, this preference is reinforced, explain the researchers, who add that the worms flock to the food and stay there longer than usual.
Lockery said: “We think this increase in existing preference is analogous to eating more food that you would crave anyway. It's like choosing pizza over oatmeal.”
The researchers said the study suggested the worms could be used to test and select drugs for human use.
Lockery said: "The fact that the human cannabinoid receptor gene is functional in C. elegans food choice experiments opens the way to rapid and inexpensive drug screening targeting a wide variety of proteins involved in signaling and cannabinoid metabolism, with profound implications for human health.
There is experimental support for the hypothesis that cannabinoids amplify the pleasurable or rewarding aspects of calorically dense foods. This phenomenon has been called hedonic amplification, while the increased food-specific consumption it engenders has been termed hedonic eating.
Around 1990, Lockery began studying the decision-making processes of Caenorhabditis elegans, translucent nematodes with a simple brain and no circulatory or respiratory system.
“It helps us situate ourselves in the animal world in a new way by reinforcing the commonality between humans, with this massive, wonderful brain, and a tiny, microscopic worm,” said Dr. Lockery, professor of biology and neuroscience, at the Washington Post.
In June 2016, Lockery was studying how C. elegans decide which bacteria to eat, as he and his team began planning their weekly gaming experience. When they thought about the possible impact of marijuana, the researchers thought, "Well, let's see what happens," Lockery said.
"We try to keep a sense of humor in what we do, which keeps us light-hearted and creative," Lockery said. “This study was born, in part, from that spirit.
While C. elegans generally preferred high-calorie foods, they ate them in greater amounts after exposure to anandamide, and they avoided low-calorie foods more than usual. In additional experiments, the researchers found that anandamide caused neurons to become more sensitive to the smells of high-calorie foods.
"This is the first time an invertebrate organism has demonstrated cravings for snacking," Lockery said. "So it's a big step up from what we believe to be the cravings limit.
While the Oregon researchers' study was supposed to be published last month, Lockery says Current Biology delayed it until April 20. Lockery hopes the study will inspire more research into how cannabis influences animals, insects and other organisms. He thinks more drugs could be tested on C. elegans to predict how they will affect humans.
Today, Lockery studies the impact of psychedelics on worm behavior.
"My project from the beginning was to try to understand how a whole, albeit tiny, brain works" I didn't expect that. But I'm grateful, it was really fun.
