New research by UT Southwestern (UTSW) has found endocannabinoids can shut down genes needed for some strands of bacteria to colonise, multiply, and cause disease.

The findings, first published in Cell, could help explain why the cannabis plant can lessen the symptoms of various bowel conditions and may eventually lead to new ways to fight gastrointestinal infections.

Cannabis and its derivatives have long been used to relieve chronic gastrointestinal conditions, including irritable bowel syndrome and inflammatory bowel disease.

Studies have shown that dysregulation of the body’s endocannabinoid system can lead to intestinal inflammation and affect the makeup of gut microbiota, the population of different bacterial species that inhabit the digestive tract.

Study leader Vanessa Sperandio, professor of microbiology and biochemistry at UTSW, and her colleagues worked with mice genetically altered to overproduce a potent mammalian endocannabinoid in various organs, including the intestines.

When the researchers infected these animals and their unmodified littermates with citrobacter rodentium, a bacterial pathogen that attacks the colon and causes marked inflammation and diarrhea, the mutant mice developed only mild symptoms compared with the more extreme gastrointestinal distress exhibited by their littermates.

Examination of the mutant animals’ colons showed far lower inflammation and signs of infection. These mice also had significantly lower amounts of the bacteria in their system, and cleared the infection days faster than their unmodified littermates. Treating genetically unmodified animals with a drug that raised levels of the same endocannabinoid in the intestines produced similar positive effects.

Sperandio said that these findings could help explain some of the effects of cannabis use on inflammatory bowel conditions.

Although studies have shown that cannabis can lower inflammation, recent research has shown that these conditions also tend to have a bacterial component that might be positively affected by plant cannabinoids.