A new study shows that mutations associated with autism block the action of brain molecules that act on the same receptors that marijuana’s active chemical acts on. Endocannabinoids are molecules that affect memory, learning, pain, and other important processes. They share a similar chemical structure with THC, the primary psychoactive component of marijuana. Endocannabinoids naturally occur in the human brain, and are responsible for synaptic signaling within the brain.
Thomas Sudhof, a cellular physiologist at Stanford University, tested mutations associated with autism in mice. Two mutations associated with autism in a synapse-adhesion protein led to deficits in prolonged endocannabinoid signaling in mice. This suggests that autism could caused by a disruption of the brain’s ability to send clear signals.
The researchers studied two mutations in neurologin-3 (NL-3), a gene encoding a protein that builds and maintains synapses. One mutation is a deletion of the entire gene, while the other, R451, contains a single amino acid substitution. Both of these mutations have been associated with autism in humans.
Sudhof and colleagues made electrophysiological recordings of the interactions between pairs of cells in the hippocampal areas of the mouse brains. They compared the brains of the mutated mice with those of normal mice. They found that cells containing cannabinoid type-1 (CB-1) receptors showed that tonic endocannabinoid signaling had been disrupted.
The researchers are not clear on why the mutations affect endocannabinoid signaling. They also do not yet understand how endocannibinoid signaling deficits are involved with the symptoms of autism. Their findings do, however, call for more research, which could lead to new and improved treatments for autism.
Another study by Danielle Piomelli of UC Irvine and Olivier Manzoni of INSERM, the French national research agency, treated mice exhibiting symptoms of Fragile-X Syndrome, a disorder that causes autistic symptoms, with novel compounds that correct the signaling of endocannibinoid transmitters in the brain. The mice showed dramatic behavioral improvements in maze tests measuring anxiety and open-space acceptance.
Do these findings suggest that medical marijuana may be the future of autism treatment? It is too early to tell, but families who are already using the drug to treat their children’s symptoms believe it has made all the difference in the world. Many children with autism are already given cocktails of drugs that may be even stronger than marijuana, with serious side effects and limited results. Meiko Hester-Perez credits medical marijuana with saving her son’s life. He was dangerously underweight, with extreme anxiety and self-injurious behaviors. Alex Echols is another child who suffered from extreme rages with self-injurious behaviors, and his family writes about their success with medical marijuana on their family blog at www.alexneedshelp.com.
The researchers involved in these studies do not advocate giving medical marijuana to children with autism, but they do concede that these findings may lead to medications and treatments that can increase the natural endocannibinoids already found in the human brain. These treatments may also be useful for many other debilitating illnesses, including anxiety, pain, depression, and obesity.
Originally posted 2013-07-21 11:28:58.