The review, “Can cannabinoids be a potential therapeutic tool in amyotrophic lateral sclerosis?,” notes that to date, the only available therapy for ALS patients is riluzole, which controls neuronal signaling. However, this drug has limited therapeutic value and only moderately increases survival — meaning novel and more effective therapeutic options for ALS patients are still needed.
Cannabinoids, the bioactive compounds of Cannabis sativa, exert their activity by binding to the CB1 and CB2 receptors.
The cannabinoid system seems to be involved in the pathology of ALS. Indeed, the spinal cord of ALS patients has been shown to present motor neuron damage triggered by immune system’s cells (microglia and macrophages) that express increased levels of the CB2 cannabinoid receptor.
“So all these data show how editing CB2-mediated processes could change ALS progression and how much the endocannabinoid system is potentially involved in reducing neuroinflammation, excitotoxicity and oxidative cell damage,” researchers wrote.
Previous studies have shown that cannabinoids have antioxidant, anti-inflammatory and neuroprotective actions in animal models of ALS. Indeed, cannabinoids can delay disease progression and prolong survival in these animals. However, only a few studies have investigated the effect of cannabinoids in human patients, which makes it difficult to interpret the results.
“According to a single observational study of patients with ALS, only the 10 percent who admitted consuming cannabis revealed moderate relief of several symptoms, including appetite loss, depression, pain and drooling,” researchers wrote. “In addition, spasticity is also a major problem for ALS patients, which reported that cannabis can subjectively improve spasticity.”
They added: “There is a valid rationale to propose the use of cannabinoid compounds in the pharmacological management of ALS patients. Cannabinoids indeed are able to delay ALS progression and prolong survival. However, most of the studies that investigated the neuroprotective potential of these compounds in ALS were performed in animal models, whereas the few clinical trials that investigated cannabinoids-based medicines were focused only on the alleviation of ALS-related symptoms, not on the control of disease progression.”
The researchers said they hope scientists will keep studying how cannabinoids may be of therapeutic use for ALS patients.