Back to Education

Alzheimer’s Disease – Medical Marijuana Research Overview

Share this article:

Alzheimer's Disease Effect on the Brain
The following information is presented for educational purposes only. Medical Marijuana Inc. provides this information to provide an understanding of the potential applications of cannabidiol. Links to third party websites do not constitute an endorsement of these organizations by Medical Marijuana Inc. and none should be inferred.

Alzheimer’s disease is the most common form of dementia, affecting over 4.5 million Americans. Studies have shown cannabis can limit the progression of the disease.

Overview of Alzheimer’s Disease

Alzheimer’s disease is a progressive type of dementia that destroys memory, behavior and thinking. In the disease, brain cells degenerate and die, which causes a steady decline in memory and intellectual and social skills. As brain cells die, the brain shrinks.

According to Mayo Clinic, scientists believe Alzheimer’s disease is caused by a combination of genetic, lifestyle and environmental factors. Age seems to play a role, as risk increases significantly at and beyond the age of 65 and the disease affects nearly half of people over the age of 85.

Hallmarks of the disease include plaques, which are clumps of protein fragments called amyloid-beta, and tangles, which are twisted fibers of the protein tau. Plaques and tangles build up in the brain and interfere with cell communication and nutrient transport, thus contributing to brain cell death.

Alzheimer’s typically begins with mild confusion or forgetfulness, but progresses over time at a rate that varies person to person. Memory loss persists and worsens, causing individuals to repeat statements or questions, forget conversations or appointments, routinely misplace possessions and eventually forget names of family members, friends, and everyday objects. Alzheimer’s will also cause a person to lose their sense of day, have difficulty finding the right words, have problems concentrating and thinking, and to experience depression, anxiety, social withdrawal, mood swings and irritability.

There is no cure for Alzheimer’s disease and medications and other management strategies may only temporarily improve symptoms.

Findings: Effects of Cannabis on Alzheimer’s Disease

Studies have determined that two of the major cannabinoids found in cannabis, tetrahydrocannabinol (THC) and cannabidiol (CBD), reduce the buildup of plaques and tangles, and therefore show viable potential as treatment options for Alzheimer’s disease.

THC has been shown to be effective at lowering amyloid-beta levels and enhancing mitochondrial function, therefore causing the researchers to conclude “that THC could be a potential therapeutic treatment option for Alzheimer’s through multiple functions and pathways” (Cao, et al., 2014). An earlier study also found THC to be effective at preventing amyloid beta aggregation, suggesting it could impact the progression of the disease (Eubanks, et al., 2006).

The brains of Alzheimer’s patients experience an over activation of microglia (cells that form myelin), which contributes to the excessive tau buildup and therefore tangles. However, CBD has been shown to modulate microglial function and control neuroinflammation (Martin-Moreno, et al., 2011). In addition, CBD has been shown to improve the survival rate of cells through a combination of neuroprotective, anti-oxidative and anti-apoptotic effects against the toxicity caused by beta-amyloid, therefore showing potential as a therapeutic option for Alzheimer’s (Iuvone, et al., 2004).

Cannabinoids provide a multi-faceted approach in the treatment of Alzheimer’s. In addition to reducing amyloid-beta levels and modulating microglial function, they protect brain cells from the deleterious effects of amyloid-beta, reduce inflammation, and support the brain’s repair process by enhancing neurogenesis (birth of new cells) (Campbell & Gowran, 2007).

States That Have Approved Medical Marijuana for Alzheimer’s Disease

Currently, eight states have approved medical marijuana specifically for the treatment of Alzheimer’s disease. These states include Arizona, Delaware, Illinois, Maine, Michigan, New Hampshire, Oregon, and Rhode Island. In Washington DC, any condition can be approved for medical marijuana as long as a DC-licensed physician recommends the treatment.

Four other states will consider allowing medical marijuana to be used for the treatment of Alzheimer’s disease with the recommendation from a physician. These states include: California (any debilitating illness where the medical use of marijuana has been recommended by a physician), Connecticut (other medical conditions may be approved by the Department of Consumer Protection), Massachusetts (other conditions as determined in writing by a qualifying patient’s physician), Nevada (other conditions subject to approval), and Washington (any “terminal or debilitating condition”).

Recent Studies on Cannabis’ Effect on Alzheimer’s Disease

      • THC found to reduce amyloid-beta levels and enhance mitochondria function, thus demonstrating potential as an Alzheimer’s disease treatment option.
        The potential therapeutic effects of THC on Alzheimer’s disease.
        http://www.ncbi.nlm.nih.gov/pubmed/25024327
      • THC prevented amyloid-beta aggregation, the key pathological marker of Alzheimer’s disease.A molecular link between the active component of marijuana and Alzheimer’s disease pathology.
        http://www.ncbi.nlm.nih.gov/pubmed/17140265

References

Alzheimer’s disease. (2014, June 17). Mayo Clinic. Retrieved from http://www.mayoclinic.org/diseases-conditions/alzheimers-disease/basics/definition/con-20023871.

Campbell, V. A., & Gowran, A. (2007). Alzheimer’s disease; taking the edge off with cannabinoids? British Journal of Pharmacology, 152(5), 655–662.

Cao, C., Li, Y., Liu, H., Bai, G., Mayl, J., Lin, X., Sutherland, K., Nabar, N., and Cai, J. (2014). The potential therapeutic effects of THC on Alzheimer’s disease. Journal of Alzheimer’s Disease, 42(3), 973-84.

Eubanks, L.M., Rogers, C.J., Beuscher, A.E. 4th, Koob, G.F., Olson, A.J., Dickerson, T.J., and Janda, K.D. (2006, November-December). A molecular link between the active component of marijuana and Alzheimer’s disease pathology. Molecular Pharmaceuticals, 3(6), 773-7.