A new study conducted in mice has found that CBD use could reverse some effects of social stress, but it did not affect anxiety-like behaviors caused by social stress.
A team of researchers from Spanish and German institutions recently published a study in the journal Neuropharmacology. They looked at whether CBD could reverse short-term behavioral effects of social stress in mice, its longer-term impact on cocaine reward, and how the endocannabinoid system might be involved in these effects.
Social stress is a type of stress caused by relationships with others and the social environment. The National Institute of Mental Health estimates that 12.1% of U.S. adults experience social anxiety disorder at some point in their lives.
CBD, or cannabidiol, is the second most common cannabinoid after THC. Over time, studies have suggested it may help with depression, anxiety, post-traumatic stress, and drug use disorders.
The study found that CBD might help reduce social stress and lower the risk of increased sensitivity to cocaine. However, the researchers pointed out that CBD did not reverse anxiety-like behaviors caused by social stress.
To understand how CBD affects social stress, researchers used mice in two experiments involving ISD episodes. Before each social defeat episode, mice received either a low or a high dose of CBD. Control groups included mice not exposed to stress and mice not given CBD.
In the first experiment, mice took part in several behavioral tests. These tests measured recognition memory, depression-like behavior, stress response, and sensitivity to cocaine using a method that checks how rewarding the drug is.
In the second experiment, researchers analyzed the expression of several genes in brain regions implicated in stress and reward, such as the serotonin transporter and cannabinoid receptors.
These experiments assessed that exposure to social defeat produced increased anxiety in mice and reduced social interactions. Mice, under social stress, also tended to develop interests for the environment associated with cocaine, which suggests enhanced vulnerability to drug reward.
CBD’s Mixed Results
The findings showed that CBD reversed the reduction in social interaction and prevented the increased preference for cocaine seen in stressed mice. This suggests that CBD may reduce social avoidance and vulnerability to the rewarding effects of drugs during stress. The findings also showed that CBD helped normalize changes in brain gene expression led by social defeat events.
However, CBD didn’t seem to prevent anxiety-like symptoms, meaning it did not reduce the anxiogenic effects of social defeat, contrasting with previous research, where observations in mice exposed to chronic unpredictable stress showed that CBD was effective; however, the authors believe this could be due to the dosage of CBD administered to the mice.
The findings, therefore, suggest that CBD may help protect against some behavioral and brain changes caused by social stress in adolescents. It seems to reverse problems with social interaction and prevent greater sensitivity to cocaine. Researchers also found that these behavior changes are linked to changes in the brain’s stress and reward systems, like those involving serotonin, cannabis-like receptors, and stress hormones.
The study, however, presents several limitations. CBD, like other cannabinoids, has the ability to produce opposite effects at different dosages. Also, the use of two different sets of animals to perform some experiments prevented the analysis of the correlation between behavioral and gene expression responses. Furthermore, the use of male mice only in this study may have influenced the analysis of the protective effects of CBD.