The Leaf THE LEAF January-February 2018 | Page 9

Treating Autism With Cannabis Now Has Scientific Support By Joshua Kaplan 16.10.2017 Wellness New research suggests that the cannabis-extract cannabidiol could help treat autism. Autism is challenging to treat pharmacologically because there’s no single cause. Autism can be caused by genetic factors, environmental factors (e.g., pesticide exposure) or a combination of both. Depending on the underlying cause, the severity of symptoms ranges across a spectrum, thus leading to the classification of autism as a spectrum disorder. But a recent study suggests that cannabidiol (CBD) could offer relief for people on the spectrum. Here's why. Autism Spectrum Disorder (ASD) is characterised by communication deficits, aberrant social behaviour, and restricted and repetitive motor behaviours. In many cases, ASD symptoms are the result of reduced inhibition in the brain. For instance, genetic causes can lead to the reduced activity of inhibitory brain cells, thus tipping the brain’s balance towards excitation. This is reflected in hypersensitivity to stimuli, such as to lights, odours, noises, or tactile stimuli that makes the individual act “abnormally” in social situations. The individual who retreats from a social situation may be doing so because they’re overwhelmed by a strong odour, anxious from direct eye contact, or a host of other reasons brought on by an insufficient inhibitory gate in the brain. In about a quarter of ASD cases, the reduced brain inhibition is so profound, and the resulting increase in brain excitation so great, that seizures result. These cases, in which epilepsy and ASD co- occur, generally reflect the severe end of the spectrum and what scientists are seeking to treat. Restoring inhibition in the brain thus seems like a reasonable approach to treatment. In mice that were genetically altered to express autism-like behaviours, scientists from Stanford University used a technique called “optogenetic” to increase the brain’s level of inhibition. The researchers could activate inhibitory brain cells by turning on a light-emitting diode (LED) in the brains of mice. When the light was off, the mice avoided social interaction. However, when they flipped the light on, the mice engaged in normal social behaviour. Unfortunately, at this point we can’t use optogenetic in humans yet. So we need a new strategy to restore the brain’s inhibition. CBD to the Rescue Our research team at the University of Washington sought to similarly treat a mouse model of autism, but instead of using light, we used CBD. CBD has gained recognition and respect in the medical community for its success in treating seizures in children with Dravet Syndrome, a severe childhood epileptic disorder characterized by frequent seizures and autism. While these clinical trials showed that CBD was an effective anti-epileptic in these patients, they never investigated CBD’s effects on ASD. In fact, no clinical study has ever looked at the potential for CBD to treat ASD. To date, there’s only one clinical study being conducted in Israel, but it’s not expected to be completed until 2019. And there’s never been a study of CBD in animal models of autism…until now.