When it comes to cannabis, most attention has focused on two parts of the plant: tetrahydrocannabinol (THC), the component that produces the “high” sensation, and cannabidiol (CBD), the part usually used for medicinal purposes. How can cannabidiol fight bacteria?
As you may already know, CBD enjoys a lot of popularity in the field of wellness. It is widely used as an alternative remedy for conditions ranging from nausea to chronic pain. Some people even find it helpful for relieving psychological symptoms such as anxiety.
Until 2018, it was difficult to get government approval to study CBD, so most of it research to its use is quite new. An emerging field of study is the search for its antimicrobial properties.
CBD kills bacteria
It turns out that CBD actually does a pretty good job of killing bacteria – even bacteria that are resistant to traditional antibiotics. Having a potential new weapon against these bacteria could save many lives.
The agent can kill both Gram-positive and Gram-negative bacteria. Both types of bacteria can become resistant to antibiotics. However, Gram-positive bacteria usually prove much more difficult to kill because they have thicker protective membranes.
Gram Positive vs Gram Negative Bacteria
The term comes from the Gram's method, a method used to detect bacteria in tissue. Dye sticks to Gram-positive bacteria and stains them bright violet. Gram-negative bacteria don't hold the dye very well, so they will only show up as pale pink.
According to a 2021 study, very little cannbidiol is needed to kill most Gram-positive bacteria. It can even destroy species that have become resistant to multiple drugs, such as:
- Methicillin-resistant Staphylococcus aureus (MRSA), which causes staph infections
- Clostridioidez difficile, which causes intestinal infections
- Streptococcus pneumoniae, which causes pneumonia or pneumococcal meningitis, an infection of the membranes surrounding your brain and spinal cord
Of the Gram-negative bacteria also studied, 20 species survived exposure to CBD. This wasn't too surprising, given that scientists haven't found any new antibiotics to treat Gram-negative bacteria since 1962.
What did the researchers find surprising? CBD can kill four types of Gram-negative bacteria, all of which have a history of drug resistance and can be life-threatening:
- Neisseria gonorrhoeae, which causes sexually transmitted gonorrhea
- Neisseria meningitides, which causes meningitis or bloodstream infection
- Moraxella catarrhalis, which causes bronchitis
- Leigionella pneumophila, which causes Legionnaires' disease
Overall, cannabidiol shows promise as a versatile antimicrobial agent. The researchers reported conflicts of interest, the most significant of which was that the pharmaceutical company Botanix funded much of the research. Botanix makes a formula that is currently undergoing clinical trials.
However, other studies with no conflicts of interest have reported similar findings. For example, a 2022 study found that CBD can fight Salmonella typhimurium, a Gram-negative bacteria that attacks your stomach and intestines. About 59 percent of salmonella infections resistant to ampicillin (a specialized antibiotic used to treat salmonella) are the typhimurium strain.
Why does this matter?
The Centers for Disease Control (CDC) estimate that 2,8 million people develop an antibiotic-resistant infection each year, and about 35.000 people die from these infections. Cannabidiol seems to kill many of the more harmful bacterial species, including:
- MRSA, which causes an estimated 323.700 hospital cases and 10.600 deaths per year
- Clostridioidez difficile, caused an estimated 223.900 hospital cases and 12.800 deaths per year
- Streptococcus pneumoniae, which causes an estimated 900.000 people and kills 3.600 per year
- Neisseria gonorrhoeae, which infects an estimated 550.000 people a year
These numbers come from the 2019 CDC report Antibiotic Resistance Threats in the United States. MRSA in particular seems to be much more difficult to build up resistance to CBD than to antibiotics. The 2021 study measured drug resistance by growing MRSA in petri dishes and measuring the minimum inhibitory concentration (MIC), or the amount of substance needed to kill all the bacteria in the dish.
The MIC of the antibiotic daptomycin increased 26-fold over 20 days of exposure. In other words, the MRSA bacteria developed so much drug resistance after 20 days that it took 26 times the original amount of daptomycin to kill it. Meanwhile, the MIC of cannabidiol only increased by a factor of 1,5. Relatively speaking, MRSA hardly developed resistance to CBD.
How does CBD fight bacteria?
There is something special about how CBD works that makes it more difficult for bacteria to adapt. Many resistant bacteria defend themselves by preventing antibiotics from entering their cells. CBD does not have to penetrate the bacteria to kill it. Instead, it attacks the membranes of bacteria and pops cells like microscopic water balloons.
Some traditional antibiotics, such as penicillin, also kill bacteria by destroying their membranes. Further research could help experts determine which specific molecules CBD targets and why CBD appears to be more effective than antibiotics at breaking down certain types of bacterial membranes.
CBD attaches to proteins
Despite this encouraging lab performance, CBD is far from ready to be used in the real world as an antimicrobial treatment. This substance has a major weakness that prevents it from becoming a miracle cure: it binds very easily to proteins.
When CBD enters your bloodstream, it will attach to proteins in your plasma. CBD doesn't kill human proteins the way it does germs, but it does attach to those cells. Only 10 to 14 percent remain 'free-floating' and available to attack bacteria.
In a nutshell, taking cannabis or CBD oil will most likely not help you fight an infection. CBD spreads through the body too much to target bacteria. Of course, research continues. Scientists continue to study ways to take advantage of CBD's bacteria-fighting potential. Possibilities include formulas to transport CBD directly to the bacteria in case of an infection, or synthetic CBD that ignores human proteins and only targets attacking bacteria.
Source: healthline.com (EN)