Early Research Is Hopeful About CBD and Depression
Scientists in Brazil have found that CBD interacts positively with serotonin receptors in the brain.
Just one dose of CBD helped mice and rats experience "acute antidepressant effects" due to increased levels of proteins in their brains' medial prefrontal cortex and hippocampus. In other words, it made the mice feel much less behavioral despair when put through certain tests.
That's the findings of a study published this year in the journal Molecular Neurobiology by researchers from the University of Sao Paulo in Brazil and Aarhus University Hospital in Denmark. They are using CBD in animal studies as a first step toward eventual human tests.
The researchers wrote, "The main finding of the present study is that CBD induces not only a robust acute, but also sustained, antidepressant-like effect in different species and distinct animal models."
Why study CBD for depression?
Why put mice and rats through tests with CBD? Research into CBD's impact on depression has been driven, in part, by the desire to find alternatives to prescription drugs. While effective in many cases, those who take drugs for depression risk a number of side effects. According to Web MD, some of the common side effects from antidepressant drugs include:
- Increased appetite and weight gain
- Loss of sexual desire
- Erectile dysfunction
- Decreased orgasm
- Fatigue and drowsiness
- Blurred vision
That's a long list. Researchers also noted that "currently available antidepressants have a substantial time lag to induce therapeutic response and a relatively low efficacy. The development of drugs that addresses these limitations is critical to improving public health."
Findings of the study.
The study put mice and rats through various tests after receiving a dose of CBD. They included forced swimming tests (FST), which involves placing the animals in a container filled with water. The FST is based on the assumption that animals will make efforts to escape but eventually exhibit immobility that researchers assume reflects behavioral despair. It also exposes animals to stress, which has been shown to contribute to depression.
The FST test and others found that the animals showed less depressed behavior, perhaps due to increased levels of proteins and the neurotransmitter serotonin in the brain. They also found that the effect happened quickly.
Previous studies had similar findings.
In 2014, a study led by researchers at the Laboratory of Panic and Respiration at the Federal University of Rio de Janeiro acknowledged some of these issues and conducted a study involving mice.
The 2014 study, which also involved mice, went into detail on depression and how it manifests. Researchers wrote that "depressed patients present symptoms such as mood changes, apathy, lack of ability to feel pleasure, increased levels of irritability, prostration, cognitive and psychomotor changes and changes in appetite and sleep regimen."
They found that CBD interacted in a positive way with the serotonin receptors in the brain. Serotonin is believed to impact a person's emotional state and feelings of well-being or happiness.
Much like the new study, researchers in the 2014 study also found that CBD "exhibited an anti-anxiety and antidepressant effects in animal models."