Alzheimer’s Disease

Alzheimer’s disease is a progressive brain disorder that causes problems with memory, cognition, and behavior. The disease, which has no known cause or cure, attacks brain cells and, as the damage spreads, can seriously affect basic human function. As the sixth-leading cause of death in the United States, an estimated five million Americans suffer from the fatal illness. The typical age of onset most commonly occurs in people over the age of 65, but some 500,000 Americans - some as young as their 30s - are estimated to have been diagnosed with the disease.

In addition to the cognitive effects of Alzheimer’s, people suffering from the illness may experience physical or verbal outbursts, general emotional distress, restlessness, hallucinations and delusions. Three commonly used FDA-approved drugs for Alzheimer’s (Aricept, Razadyne and Exelon) share the same adverse effects, including: nausea, vomiting, loss of appetite and increased frequency of bowel movements.

THC as treatment to both symptoms and progression

In a study published in the journal Molecular Pharmaceutics (August 2006), scientists at The Scripps Research Institute found the main active ingredient in cannabis, THC, inhibits the formation of amyloid plaque, the primary pathological marker for Alzheimer’s disease. With its strong inhibitory abilities, the study said, THC “may provide an improved therapeutic for Alzheimer’s disease” that would treat “both the symptoms and progression” of the disease.

“When we investigated the power of THC to inhibit the aggregation of beta-amyloid,” said Kim Janda, Ph.D., who is Ely R. Callaway, Jr. Professor of Chemistry at Scripps Research, a member of The Skaggs Institute for Chemical Biology, and director of the Worm Institute of Research and Medicine, “We found that THC was a very effective inhibitor of acetylcholinesterase. In addition to propidium, we also found that THC was considerably more effective than two of the approved drugs for Alzheimer’s disease treatment, donepezil (Aricept) and tacrine (Cognex), which reduced amyloid aggregation by only 22 percent and 7 percent, respectively, at twice the concentration used in our studies. Our results are conclusive enough to warrant further investigation.”

The effect of cannabidiols

Another study, published in the Journal of Molecular Medicine (March 2006), found cannabidiol, a component also found in cannabis, to be an antioxidant neuroprotective agent in neurodegenerative diseases. “A massive accumulation of beta-amyloid (Abeta) peptide aggregates has been proposed as pivotal event in AD (Alzheimer’s Disease). Abeta-induced toxicity is accompanied by a variegated combination of events including oxidative stress. The Wnt pathway has multiple actions in the cascade of events triggered by Abeta, and drugs that rescue Wnt activity may be considered as novel therapeutics for AD treatment.”

Cannabis as preventive medicine

In addition to alleviating the effects of AD in patients, preliminary research suggests that cannabis may also reduce the risk of developing the disease by reducing inflammation in the brain. “The findings, released at the Society for Neuroscience meeting in Atlanta, may explain studies showing those who regularly used marijuana in the 1960s and 1970s are now less likely to develop Alzheimer’s disease than their non-smoking contemporaries.”