AUGUSTA, Ga. — Cannabidiol, or CBD, continues to gain support as a remedy for everything from stress to bacterial infections. A new study reveals marijuana’s non-psychoactive ingredient may also be the key to stopping the triggers for Alzheimer’s disease. Researchers from the Medical College of Georgia at Augusta University say high doses of CBD restores the function of key proteins that clean up beta-amyloid plaque buildups in the brain. These clumps are one of the major causes of Alzheimer’s, the most common form of dementia.
Their study finds a two-week treatment course in mice boosted the proteins TREM2 and IL-33. Both contribute to the brain’s immune cells being able to clean out dead cells and other debris in the body. When plaques pile up in the brain, they start interfering with the communication between neurons and lead to brain cell death. Levels of both proteins decrease in patients with Alzheimer’s.
For the first time, investigators report that CBD treatments normalized the levels of these proteins. CBD also helped to improve cognitive function in mice with a form of early onset familial Alzheimer’s. Dr. Babak Baban, an immunologist and associate dean for research in the Dental College of Georgia, says CBD helped to reduce levels of IL-6. Researchers believe this particular immune protein has a link to high levels of inflammation in Alzheimer’s patients.
“Right now we have two classes of drugs to treat Alzheimer’s,” neurologist Dr. John Morgan explains in a university release. “But we have nothing that gets to the pathophysiology of the disease.”
Currently, one class of Alzheimer’s medications increases the levels of the neurotransmitter acetylcholine, which the disease also reduces. The other class targets NMDA receptors that handle communication between the neurons and are vital for memory functions.
Tremendous cognitive boosts due to CBD
In the case of IL-33, the study finds CBD helps the protein sound the alarm that there are “invaders” in the brain that need sweeping out. Researchers add that IL-33 expression is highest in the brain, which is why it’s so important for fighting beta-amyloid plaque accumulation. Dr. Baban says IL-33 helps to turn down inflammation tied to Alzheimer’s and restores immune balance.
For TREM2, CBD allowed this protein to combine with other proteins on the surface of cells to transmit signals which activate immune cells. In the brain, TREM2 helps to activate microglial cells. These cells are exclusive to the brain and help eliminate invading viruses and damaged neurons.
The results of the mice treatments show their levels of IL-33 and TREM2 increased by seven and ten times, respectively.
Along with higher protein levels, mice performed better in cognitive assessment tests. The animals were better able to differentiate between familiar items and new ones and also displayed improved movement as well.
Study first author Dr. Hesam Khodadadi notes that people with Alzheimer’s may experience movement problems like stiffness or an impaired gait. In mice, the disease causes them to move in an endless circle. However, Khodadadi reports this disorder stopped after treatment with CBD.
Can CBD help prevent Alzheimer’s in its early stages?
The study worked with mice experiencing the late stages of early onset Alzheimer’s; giving the subjects high doses every other day for two weeks. Khodadadi says the next step will be to determine the best doses for patients and experiment with CBD treatments administered earlier in the disease’s progression.
Researchers are also exploring if they can administer these CBD doses using an inhaler, which would improve the delivery of CBD to the brain. Currently, researchers gave the mice CBD doses in their stomachs and allowed it to filter throughout the body from there.
Study authors are also hopeful CBD will have the same impact on other versions of Alzheimer’s. Familial Alzheimer’s is an inherited, genetic version of the disease that typically surfaces in a person’s 30s or 40s. About 10 to 15 percent of patients have early onset familial Alzheimer’s.
Dr. Baban says the team is already looking to establish CBD’s effectiveness on the more common forms or Alzheimer’s in clinical trials. In these cases, plaques and neurofibrillary tangles both contribute to brain cell death. The study author notes that beta-amyloid plaques usually start to form in the brain 15 to 20 years before dementia symptoms even appear.
The study appears in the Journal of Alzheimer’s Disease.