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Antibiotics are one of the most widely used medications since their appearance in the health field and have been infallible in eliminating bacterial infections for decades. However, its effectiveness is declining due to the increasing presence of antibiotic-resistant bacteria.
Superbugs: The Next Health Hazard
Antibiotic-resistant bacteria , also known as superbugs, present a health hazard that the World Health Organization (WHO) itself has listed as a research priority for several years.
The presence of superbugs is on the rise , especially in populations where antibiotic use is high. Within these countries, antibiotics can be obtained from pharmacies without a prescription, so their use is usually higher than necessary.
There are more and more diseases caused by bacterial infections that are resistant to being treated with simple antibiotics, which has a direct effect on the duration of the disease, the severity of symptoms and health spending.
In addition, as we have already seen in the pandemic caused by SARS-CoV-2, highly globalized population dynamics allow infectious pathogens to travel from one point on the planet to the other in just a few hours. So today’s problem in Spain can become tomorrow’s problem in Vietnam, and vice versa.
Antibiotic-resistant bacteria are capable of surviving standard treatment and proliferating in environments where their companions, which do not have this advantage, quickly die. This selective pressure makes it easy for bacterial strains to become enriched with superbugs over time.
New traps for old enemies
Faced with this situation, the WHO proposes general recommendations , not only for researchers and health professionals, but also for citizens and patients. In general, all of them focus on not taking antibiotics without a medical prescription and, when doing so, follow the indicated guidelines . This practice, together with normal hygiene measures, can have a great impact.
In the field of research, many groups have been devising alternative or complementary strategies to eliminate these resistant bacteria along with those sensitive to antibiotics. In recent years we have seen the development of bacteriophage viruses or new drugs.
A new study proposes the use of a molecule isolated from a mushroom to treat antibiotic-resistant bacteria, specifically the bacterium Pseudomonas aeruginosa . This bacterium was listed by the WHO as the second most harmful superbug.
Pseudomonas aeruginosa is an opportunistic pathogen that infects patients whose immune system is not working properly, infecting the respiratory tract, wounds, and tissues, and can cause sepsis (generalized infection). In this situation, if the antibiotics do not work, it can be fatal for the patient.
An (almost) magic mushroom
Bacteria have evolved alongside many other living organisms, and co-evolutionary strategies between parasites and the beings they infect have been discovered on numerous occasions. The fungus Lentinula edodes is a clear example, as it has antibacterial properties .
This Chinese or shiitake mushroom has caught the attention of a research group from the University of Granada, whose focus is to identify natural mechanisms to use them as treatments against bacteria due to their antibacterial capacity.
A study recently published by this team in the journal Frontiers in Microbiology has presented the results of the analysis of the mycelium extract of this fungus as its ability to eliminate the bacterium Pseudomonas aeruginosa .
Experiments showed that these mushroom extracts affected the movement and metabolism of this bacterium. In addition, they observed that some genes involved in the creation of biofilm (a “bio-film” that acts as a protective barrier against external agents) were partially deactivated.
These observations were confirmed with infection models in cell cultures. In the presence of the mushroom molecule, the bacterium was not able to infect with such virulence and effectiveness .
A new hope against superbugs
These results need to be verified in animal models before human studies can begin. Even if all the studies are positive, it will be necessary to carry out many checks to ensure that it is a candidate to be a new drug against Pseudomonas aeruginosa .
Although we will not have the Lentinula edodes fungus molecule in pharmacies in the recent future, these results open the door to possible alternatives to combat infections caused by superbugs .
It is possible that what has been learned in this article is not only effective against this bacterium, but can also be applied to other bacteria from other families, especially if this mechanism is based on a highly conserved bacterial process in evolution.
References:
Kisler and Zlokovic. 2022. How the brain regulates its own immune system. Nat Neurosci. doi: 10.1038/s41593-022-01066-w
World Health Organization. Newsroom: Antibiotic resistance. 31 July 2020.
