New Approach Blocks Staph Infections
Research supported by the National Institutes of Health has blocked staph infections in mice, and coming human trials will show whether it solves an worrisome trend: a staph bacterium that is increasingly resistant to antibiotics. The new approach, using a drug that had been tested in clinical trials as a cholesterol-lowering agent, was described in the February 14 online edition of Science.
"By following their scientific instinct about a basic biological process, the researchers made a surprising discovery with important clinical implications," said NIH Director Dr. Elias Zerhouni. "Although the results are still very preliminary, they offer a promising new lead for developing drugs to treat a very timely and medically important health concern."
This work was supported by three NIH units: the National Institute of General Medical Sciences, the National Institute of Allergy and Infectious Diseases, and the National Institute of Child Health and Human Development. NIH explains that a pigment turns Staphylococcus aureus golden and acts as an antioxidant to block the reactive oxygen molecules the immune system uses to kill bacteria. The researchers theorized that blocking pigment formation in staph may restore the immune system's ability to thwart infection. Reading a magazine on microbial research in 2005, Eric Oldfield, Ph.D., of the University of Illinois at Urbana-Champaign read how University of California, San Diego researchers knocked out a gene in staph's pigment-making pathway to create colorless, less pathogenic bacteria. "I looked at the metabolic pathway and noticed that it was similar to the one for the production of cholesterol in humans," said Oldfield, who is the senior author of the Science paper. Colleagues at Cedars-Sinai Medical Center in Los Angeles tested eight different drug compounds and found three blocked pigment production in laboratory tests. When the researchers treated mice infected with aureus with one of the compounds, the bacterial population was reduced by 98 percent.