The conclusion belongs to a new study

Feb 8, 2010 14:21 GMT  ·  By

Investigators have proposed over the years that the light drug marijuana may play an important role in tempering, or even reducing the effects of the neurodegenerative condition Alzheimer's. But now, Canadian researchers at the University of British Columbia (UBC), and the Vancouver Coastal Health Research Institute (VCHRI) throw some doubts on previous conclusions, in a new study they published in the latest issue of the respected scientific journal Current Alzheimer Research, PhysOrg reports.

“As scientists, we begin every study hoping to be able to confirm beneficial effects of potential therapies, and we hoped to confirm this for the use of medical marijuana in treating Alzheimer's disease. But we didn't see any benefit at all. Instead, our study pointed to some detrimental effects,” UBC Faculty of Medicine Professor of Psychiatry Dr. Weihong Song, who is a Canada Research Chair in Alzheimer's Disease at the university, says.

The expert is also a member of the UBC Brain Research Center, and the director of the Townsend Family Laboratories at the university. The researcher and his team conducted their work on unsuspecting mice that had been specifically engineered to carry the human genetic mutations that triggered the development of Alzheimer's. For several weeks, the animals were given cannabinoids, substances belonging to a class of compounds that include tetrahydrocannabinol (THC), the main psychoactive ingredient in marijuana. The substance the mice received was called HU210.

According to Song, this was 100 to 800 times more powerful than THC. The team determined that the mice that had been given the highest concentrations of the stuff actually had less brain cells at the end of the study, even less than those that were given low amounts of HU210. “Our study shows that HU210 has no biological or behavioural effect on the established Alzheimer's disease model. More studies should be done before we place much hope in marijuana's benefits for Alzheimer's patients,” Song concludes.