Cannabis could hold the key to preventing neurodegenerative diseases like Parkinson’s and Alzheimer’s, according to new research.
Cannabis is also said to contain a chemical that protects brain cells against ageing.
The compound CBN (cannabinol) is non-psychoactive, meaning it doesn’t get people high.
Senior author Professor Pamela Maher said: “We’ve found cannabinol protects neurons from oxidative stress and cell death – two of the major contributors to Alzheimer’s.
“This discovery could one day lead to the development of new therapeutics for treating this disease and other neurodegenerative disorders – like Parkinson’s disease.”
Studies on medical cannabis have focused on the active substances THC (delta-9 tetrahydrocannabinol) and CBD (cannabidiol), HullLive reports.
There is not much known about the therapeutic possibilities of CBN, which is molecularly similar but less heavily regulated.
The team at the Salk Institute in California had previously identified the neuroprotective properties, but now they say they have worked out the mechanism.
Lab experiments showed CBN stops a type of cell death called oxitosis which is triggered by the loss of an antioxidant called glutathione.
During the study, nerve cells were treated with CBN – before oxitosis was triggered.
In further analysis, CBN was found to have boosted the mitochondria, which is the power stations of cells.
Oxidation made damaged neurons curl up like doughnuts, a change that is seen in the brains of people with Alzheimer’s.
When the cells were injected with CBN they maintained their healthy shape – and kept them functioning well.
Prof Maher said: “We were able to directly show maintenance of mitochondrial function was specifically required for the protective effects of the compound.”
The study also showed CBN did not activate cannabinoid receptors – meaning that medications containing it would work without making the person taking it “high”.
First author Dr Zhibin Liang said: “CBN is not a controlled substance like THC – the psychotropic compound in cannabis.
“Evidence has shown CBN is safe in animals and humans. And because CBN works independently of cannabinoid receptors, it could also work in a wide variety of cells with ample therapeutic potential.”
The study has implications for a range of neurodegenerative diseases such as Parkinson’s – which is also linked to glutathione loss.
Prof Maher said: “Mitochondrial dysfunction is implicated in changes in various tissues – not just in the brain and ageing.