Smoking Cannabis Effect Extends Beyond the Mouth

Diving deeper into the effects of cannabis-caused changes on the bacteria living in the mouth and their impacts on the neurological disease will be explored by researchers from the University of North Carolina at Chapel Hill, U.S. Cannabis is the most widely used drug in the U.S. and can have positive mental effects, such as reducing anxiety. However, long-term use can lead to impaired memory, learning, and motor skills, said Jiang. Smoke also contains harmful compounds from combustion that affect oral health.

Changes in oral bacteria have been linked to cardiovascular diseases, preterm birth, and even Alzheimer’s disease. Such unnatural changes can allow harmful bacteria to thrive in the mouth and even enter the bloodstream, damaging other organs, such as the brain.

Cannabis Use: A Joint Problem for Oral and Mental Health

Researchers showed in a December 2021 study that frequent cannabis use alters the oral microbiome. They found unusually high levels of the bacterium Actinomyces meyeri in frequent cannabis users but not in tobacco or cocaine users.

In general, the amount of A. meyeri should be very low in a healthy oral microbiome. Even the mice orally exposed to A. meyeri for six months showed increased inflammation and more amyloid-beta proteins in their brains. These proteins are thought to be linked to long-term memory loss and Alzheimer’s disease.

After seeing these changes in mice given this bacterium, researchers became very intrigued by what was happening in their brains. The new study will explore the mechanisms underlying the link between high levels of A. meyeri in the mouth of frequent cannabis users and neurological disease.

Psychological dependency on a drug can have harmful neurological effects, but they don’t know what is driving these effects in heavy cannabis users. Oral health affects mental health is also a known fact. However, these things don’t explain the role of oral bacteria.

Although earlier work showed that the cannabis-altered oral microbiome played a role in neurological changes, it did not specifically look at what component of cannabis caused those changes.

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Cannabis contains both psychoactive (THC) and non-psychoactive (CBD) components, which interact with the brain and nervous system in different ways. Now, they want to identify the specific effects of THC and CBD on oral microbiome dysbiosis and mental health.

Cannabis and Alzheimer’s Disease: What’s the Link?

For that purpose, mice are exposed to different levels of THC and CBD to determine their effects on levels of A. meyeri in the bacteria living in the mouth.

They found that long-term exposure to THC, but not CBD, will increase levels of A. meyeri in saliva and lead to harmful neurological effects in mice. Researchers will now move beyond mouse models to humans with cannabis use disorder to see how changes in their oral microbiomes affect memory.

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They expect memory-related deficits to be associated with greater levels of A. meyeri in frequent cannabis users compared with nonusers.

Anyway, the research highlights the importance of oral health and its complex relationship with other diseases. Therefore, anyone using cannabis frequently should pay particular attention to their oral hygiene.

In the future, it may also be useful to screen for certain bacteria as biomarkers of different diseases that affect the brain, such as Alzheimer’s disease.



Source-Eurekalert