In 2017, a heartbreaking event occurred in a Nevada hospital when a woman being treated for pneumonia tragically died from multiple organ failure and sepsis caused by a bacterial strain resistant to an alarming 26 different antibiotics. These superbugs, or antibiotic-resistant bacteria, represent one of the most urgent public health challenges worldwide.
In the fight against these lethal pathogens, researchers from Texas A&M University have revealed that curcumin, the substance responsible for turmeric’s vibrant yellow hue, may be effective in combatting antibiotic resistance.
The team demonstrated that by intentionally feeding bacteria curcumin and subsequently activating it with light, harmful reactions can be initiated within the bacteria, ultimately leading to their death. This method effectively reduces the prevalence of antibiotic-resistant strains and restores the efficacy of traditional antibiotics.
The findings of this study have been published in the journal Scientific Reports.
Historically, infectious diseases were the leading cause of death and disability worldwide. The introduction of antibiotics significantly contributed to an increase in average human lifespan by 23 years. However, in recent decades, while the discovery of new antibiotics has stagnated, antibiotic-resistant bacteria have surged, giving rise to difficult-to-treat superbugs like methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus, and pneumonia. It is estimated that infectious diseases may once again become the primary cause of human death, potentially claiming up to 10 million lives annually.
“When bacteria develop resistance to standard antibiotics, we face what is termed an antibiotic catastrophe,” explained Dr. Vanderlei Bagnato, a professor in the Department of Biomedical Engineering and the senior author of the study. “To address this issue, we must discover alternative methods to either eliminate these superbugs or innovatively modify bacterial processes so that antibiotics regain their effectiveness.”
Bacteria inherently exhibit variations within their populations. This diversity can lead to differences in responses to antibiotics, which can facilitate treatment resistance if certain strains survive exposure to antimicrobial treatments and proliferate. Therefore, the researchers aimed to reduce bacterial heterogeneity to better manage resistance.
Photodynamic inactivation, a promising method against bacterial resistance, employs light and light-activated molecules known as photosensitizers to generate reactive oxygen species capable of killing microorganisms by disrupting their metabolic functions. In their studies, the team utilized curcumin, which also serves as a natural food source for bacteria, to test this method on strains of Staphylococcus aureus resistant to amoxicillin, erythromycin, and gentamicin.
The researchers subjected the bacteria to multiple cycles of light exposure and compared the minimal concentrations of antibiotics required to eliminate the bacteria after exposure to light vs those that did not receive light treatment.
“In a mixed bacterial population where some strains are resistant, using photodynamic inactivation helps refine the bacterial distribution, leaving behind strains that are more uniform in their antibiotic response,” stated Bagnato. “This makes it easier to determine the exact antibiotic dosage necessary to eradicate the infection.”
The study team pointed out that employing photodynamic inactivation with curcumin holds significant promise as a complementary treatment alongside antibiotics for diseases like pneumonia that are caused by antibiotic-resistant bacteria.
“Photodynamic inactivation is a cost-effective treatment alternative, essential for lowering medical costs not only in developing countries but also in the United States,” remarked Dr. Vladislav Yakovlev, a professor in the Department of Biomedical Engineering and a co-author of the study. “Its potential applications in military medicine are significant, as this technology could effectively treat wounds in combat scenarios and help prevent the onset and spread of antimicrobial resistance, a critical issue in warfare.”
The research contributors include Dr. Jennifer Soares, the primary author of the paper, and Dr. Kate Blanco from the Institute of Physics of São Carlos at the University of São Paulo in Brazil.
This research received funding from various organizations including the São Paulo Research Foundation, the National Council for Scientific and Technological Development, the Cancer Prevention and Research Institute of Texas, the Governor’s University Research Initiative, the Air Force Office of Scientific Research, and the National Institutes of Health.
