A recent study has uncovered a natural remedy within various plants that effectively inhibits the development of drug-resistant Candida fungi, including the highly dangerous Candida auris. The findings, led by scientists at Emory University and published in the ACS Infectious Diseases journal, present a promising solution to combat this global health menace.
In straightforward terms, researchers conducted experiments in lab dishes and found that a water-soluble tannin named PGG, present in many plants, can thwart the growth of four different Candida fungi species, inhibiting approximately 90% of their growth. The secret behind PGG’s inhibitory power lies in its ability to trap iron molecules, essentially depriving these fungi of a vital nutrient.
Unlike existing antifungal medications, which can contribute to drug resistance, PGG works by starving the fungi rather than directly attacking them. Importantly, lab experiments also indicated that PGG had minimal toxicity to human cells.
Candida infections that resist treatment are becoming a serious problem in healthcare. Few new antifungal treatments are in development, making this discovery particularly significant. Cassandra Quave, the senior author of the study, emphasized the potential of this approach in dealing with these infections, including the deadly Candida auris, which is often resistant to multiple drugs
and poses a significant threat to global health.Candida is a type of yeast commonly found on the skin and in the digestive systems of healthy individuals. Sometimes, certain Candida species, like Candida albicans, can overgrow and cause mild infections. In more critical scenarios, Candida has the potential to penetrate deeper within the body, resulting in bloodstream infections or impacting vital organs like the kidneys, heart, and brain. Those with compromised immune systems, including many hospital patients, are most susceptible to invasive Candida infections, which are evolving to resist current treatments.
Back in 2007, a novel Candida species known as C. auris surfaced within a patient at a Japanese hospital. Subsequently, it has triggered epidemics in medical institutions across more than a dozen countries globally, with the United States alone reporting over 3,000 clinical cases.C. auris is particularly concerning because it is often resistant to multiple drugs and has a high mortality rate.
Dr. Cassandra Quave, an ethnobotanist, is leading the charge in identifying potential new medications from traditional plant use. Her lab houses the Quave Natural Product Library, containing thousands of natural products from plants and fungi collected globally.
The Brazilian peppertree, traditionally used by Amazonian healers for skin infections and other ailments, drew Quave’s attention. Her research showed that it contains PGG, a compound with antibacterial, anticancer, and antiviral properties.
To test PGG’s effectiveness against Candida, the researchers conducted lab experiments. They discovered that PGG blocked approximately 90% of the growth in 12 strains of four Candida species, including C. albicans and multidrug-resistant C. auris.
PGG’s ability to bind with iron molecules plays a crucial role in its antifungal properties. When more iron was introduced into the environment, beyond what PGG could sequester, the fungi resumed normal growth. Additionally, PGG displayed good tolerance in human kidney, liver, and epithelial cells.
While PGG shows promise, it’s currently being investigated primarily as a topical treatment for fungal skin infections. Future research will assess its effectiveness in mice. Moreover, provisional patents have been sought for the use of PGG in mitigating fungal infections. A
The researchers also plan to explore PGG’s potential as a broad-spectrum antimicrobial, which could be valuable for treating various infections, especially those resulting from acute injuries.
The research has received valuable contributions from scientists at the University of Toronto and has garnered support through grants generously provided by institutions including the National Institutes of Health, National Center for Complementary and Integrative Health, the Jones Center at Ichauway, the CIHR Frederick Banting and Charles Best Canada Graduate Scholarship, and the Canadian Institutes of Health Research Foundation.
This discovery holds the promise of a natural and effective solution against drug-resistant Candida fungi, offering hope in the fight against this emerging global health threat.
