A team of San Diego scientists recently put out a study suggesting an active ingredient in marijuana may be helpful in warding off Alzheimer’s disease.
But the results need to be confirmed in future research. One of the scientists worries those follow-up studies may not happen due to restrictions on research involving pot.
"To work on anything related to marijuana or these psychoactive drugs in the United States is, from a scientific point of view, extremely difficult," said the study's senior author, Dave Schubert of the Salk Institute.
"There are so many rules and limitations on what can be done," he said.
In lab experiments, Schubert and his colleagues exposed human brain cells to THC, a chemical compound found in marijuana. They found that by stimulating cannabinoid receptors in these cells, THC reduced the inflammation and plaque build-up that precede the onset of Alzheimer's.
Schubert said these results are promising, but preliminary. To know if THC can actually keep Alzheimer's at bay in patients, follow-up studies will need to confirm this effect in animals and humans. That won’t be easy, he said, because the Drug Enforcement Administration considers marijuana to be a highly dangerous drug with no medical use.
"Best to let the science do its work and sort these things out," Schubert said.
Schubert said his lab's work on marijuana and Alzheimer's is effectively at a standstill, considering the funding and regulatory hurdles involved in securing large amounts of THC for use in living organisms. He hopes the DEA will reclassify the drug when they take up the issue next month.
"The Salk study opens an intriguing new possibility," said Igor Grant, a UC San Diego medical marijuana researcher who was not involved in the study.
If the results hold up in future studies, Grant said, "Cannabinoids might be useful in preventing progression to clinical dementia if a diagnosis can be made at an early preclinical stage."
Barth Wilsey, another UC San Diego scientist who was not involved in the study, notes that previous studies have not found evidence for marijuana being effective against symptoms of dementia.
But Wilsey, who has done research showing marijuana can relieve neuropathic pain, hopes the DEA will lift regulations he said have stymied research into the drug's effect on neurodegenerative diseases.
"Only then will scientific answers be made more readily available in evaluating the suitability of whole plant cannabis for sufferers of these tragic neurodegenerative disorders," he said.
