Earthworms are also appetizing, study reveals

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Shortly after Oregon legalized cannabis in 2015, some researchers in the state embarked on a bizarre experiment one Friday afternoon.

The team worked with a species of tiny nematode called Caenorhabditis elegans, which is smaller than a human eyelash, to understand its food preferences and, on the spur of the moment, soak the worm in cannabinoids, active substances found in weeds. Did.

It turned out that the worms responded, the cannabinoids making them hungry for foods they liked and less hungry for foods they didn’t like. He revealed that he was engaged in feeding.

“The very fact that the nematode was hedonistically feeding was astounding. Worm munchies. Really?” The study was published Thursday in the scientific journal Current Biology. Until now, cannabinoids were known to only affect humans and other mammals – they want to eat more and crave the tastiest, most calorie-dense foods.

But the worms weren’t eating up the pile of junk food. They were eating different types of bacteria.

By measuring the worms’ swallowing speed, Rockery and his team determined that the cannabinoids increased the amount of specific bacterial blends the worms ate, making them hungrier. By placing them in a T-shaped maze that mixed bacteria with unfavorable food, they showed their craving for a more palatable food.

The worms have also been genetically engineered to make certain neurons and muscles fluoresce, with green dots indicating neurons that respond to cannabinoids.

Lockery added that the active ingredient in cannabis “made the worm’s olfactory neurons more sensitive to preferred foods and less sensitive to less preferred foods,” but why did this happen? was “very mysterious” and he planned to track it down.

In humans and other animals, cannabinoids work by binding to cannabinoid receptors in the brain, nervous system, and other parts of the body. Said. These receptors typically respond to related molecules found naturally in the body known as endocannabinoids. The endocannabinoid system plays important roles in feeding, anxiety, learning and memory, reproduction and metabolism.At the molecular level, the cannabinoid system of these worms is They are very similar to humans and other animals.

“Our findings help us to more fully understand our place in the animal kingdom,” Rockery said in an email. It shows that our decision-making is influenced by factors that we can do.”

C. elegans is an ideal laboratory animal for studying neurons. Despite having a small number of neurons (302 neurons compared to her 86 billion neurons in humans), the worm has a nervous system that includes a primitive brain.It’s also the first animal I ever owned. Its genome was sequenced in 1998.

Lockery said the study could accelerate the discovery of new treatments for metabolic disorders, including obesity.

“Drug discovery often starts with gene discovery, and C. elegans is the primary organism for this,” he said.

“Genetic studies in C. elegans are rapid and inexpensive. …Our demonstration that human cannabinoid receptors function in regulating appetite in worms highlights the profound similarities between humans and worms in regulating metabolism.” increase.”

But what the research really shows is, “Wait, what?” Friday afternoon moments have scientific value.

“I found both positive results interesting and thought-provoking for the public. It’s a science that first makes you laugh and then makes you think,” Rockery said.