Although previous research found that cannabis use may lead to social withdrawal, until now, the mechanisms behind the phenomenon were unknown. Now, from studying mice, researchers may have found how regular cannabis use may impact sociability.
The study comes after previous results in which the researchers found that cannabinoid receptors exist on the membranes of mitochondria (the so-called ‘powerhouses’ of the cell) that lie within astrocytes. Playing an important role in energy metabolism in the brain, these cells work by capturing glucose from the blood and metabolizing it into lactate to then ‘feed’ neurons.
To see how cannabis compounds may impact their function, the researchers exposed mice to tetrahydrocannabinol (THC), the psychoactive compound in cannabis. In doing so, they found that the activation of the astrocytes’ cannabinoid receptors by THC reduced their ability to metabolize glucose.
This meant that the astrocytes were less able to convert glucose into ‘food’, and ultimately compromised the function of surrounding neurons. The researchers suspect that this compromise then led to a reduction in social interactions between the mice for up to 24 hours.
“Our study is the first to show that the decline in sociability sometimes associated with cannabis use is the result of altered glucose metabolism in the brain. It also opens up new avenues of research to find therapeutic solutions to alleviate some of the behavioral problems resulting from exposure to cannabis. In addition, it reveals the direct impact of astrocyte energy metabolism on behavior,” says Giovanni Marsicano, lead author of the study.
Given the rising popularity of cannabis-based products, the researchers believe that their findings can help generate a better understanding of how the body’s cannabinoid receptors react to cannabis compounds. In particular, they hope their research will inform better management of patients who may need to use cannabis for therapeutic reasons.