While chili peppers and marijuana have very different effects on the brain, a new study shows that, when consumed, their impact on the gut may not be so dissimilar.
Researchers have found that capsaicin - the compound that gives chili peppers their heat - targets a receptor in the gut that produces a compound called anandamide, which is chemically similar to the compounds in marijuana.
In the guts of mice, anandamide produced by capsaicin consumption was found to reduce inflammation by summoning anti-inflammatory immune cells, and it even reversed type 1 diabetes in the rodents.
Study co-author Pramod Srivastava, professor of immunology and medicine at the UConn Health School of Medicine in Farmington, CT, and colleagues say that their findings suggest that both chill peppers and edible marijuana may help to treat type 1 diabetes and colitis (inflammation of the colon).
Furthermore, the team says that the study raises some important questions about how the immune system, the gut, and the brain are linked.
The researchers recently reported their findings in the Proceedings of the National Academy of Sciences.
The immune system and the brain \\\'share a common language\\\'
Srivastava and colleagues came to their findings by administering capsaicin to mouse models of type 1 diabetes and analyzing how the chili pepper compound affected the gut.
The researchers found that capsaicin targets and binds to a receptor called TRPV1, which is present on specialized cells in the gastrointestinal tract. This led to the production of anandamide.
Further investigation revealed that anandamide not only interacts with TRPV1 in order to produce more anandamide, but it also works with a receptor called CX3CR1, which recruits a type of macrophage - or white blood cell - that reduces inflammation.
As anandamide levels increased, so too did the levels and activity of the anti-inflammatory macrophages.
In the mouse models, both capsaicin and anandamide independently reduced gut inflammation, and the chili pepper compound even reversed type 1 diabetes in the rodents.
The team notes that anandamide is chemically comparable to the compounds found in marijuana, and it binds to cannabinoid receptors in the brain. This not only indicates that edible marijuana may reduce gut inflammation, but it sheds further light on the relationship between the gut, the immune system, and the brain.
\\\"This allows you to imagine ways the immune system and the brain might talk to each other. They share a common language,\\\" says Srivastava.
The authors say that future research should investigate how edible marijuana impacts gut inflammation in humans. Collecting such data should now be a simpler process due to the legalization of the drug in certain states.
\\\"I\\\'m hoping to work with the public health authority in Colorado to see if there has been an effect on the severity of colitis among regular users of edible weed,\\\" says Srivastava.
The researchers also plan to determine the precise molecular pathway by which chili peppers and edible marijuana reduce gut inflammation, as well as whether there are other receptors targeted by anandamide.