We’re so used to medicines being able to easily cure our simple ailments that it’s hard to imagine a world without effective antibiotics. But antibiotics are increasingly powerless against superbugs–powerful bacteria that have evolved to resist our medical advances.
So what comes next? One option may be to examine traditional plant remedies to see if there are any active ingredients we could deploy as medicine. And one of those remedies is the shrub-like Brazilian peppertree, known as an invasive weed in Florida and used as a treatment for infections by indigenous people in the Amazon.
Researchers at Emory University in Atlanta took the Brazilian peppertree (Schinus terebinthifolia) and tested it in the lab, isolating the various chemical components of the plant and pitting them against known disease-causing bacteria. In its native Brazil, the plant is known for its antiseptic and anti-inflammatory properties. The Emory researchers, led by ethnobotanist Cassandra Quave, found that the peppertree does indeed have bug-zapping properties, slowing the growth of skin lesions in mice that had been infected with antibiotic-resistant Staphylococcus aureus (MRSA) bacteria.
Instead of outright killing bacteria, the peppertree extract works by disrupting it. The extract represses a gene responsible for allowing the bacteria cells to communicate with each other. This, in turn, stops the cells from effectively working together. “It essentially disarms the MRSA bacteria, preventing it from excreting the toxins it uses as weapons to damage tissues,” Quave said on Emory’s eScienceCommons blog. “The body’s normal immune system then stands a better chance of healing a wound.”
Antibiotics have become less effective because they annihilate bacteria, allowing only the strongest to escape unscathed. These Darwinian heroes go on to breed into superbugs, which resist antibiotics. The peppertree’s active compounds have a different approach. By disrupting the MRSA instead of killing it, there’s no strategy that the bugs can understand and overcome to resist the peppertree.
Seeking out folk medicines and testing them individually against known disease-causing bacteria may seem like slow, painstaking work, but it might be essential in fighting disease now that antibiotic effectiveness is on the wane. And it may prove a better strategy in the long-term, because the diseases won’t be locked in an arms race and forced to mutate to survive.