For the generations of high school students whose English class assignments included reading Joseph Kesselring’s play, “Arsenic and Old Lace,” the idea of arsenic as an aid to health seems either amusing or frightening.
But a group of Florida International University researchers from the Herbert Wertheim College of Medicine and an international team from Japan have discovered a new broad-spectrum antibiotic that contains arsenic, FIU announced Tuesday.
Broad-spectrum means “an antibiotic is effective against many types of bacteria,” FIU’s Barry Rosen, the co-senior author of the study that was published Monday in Nature’s Communication Biology, said of arsinothricin, also known as AST.
This is important, FIU’s scientists explained, because antibiotic resistance — when the body’s immune system doesn’t react to the antibiotic’s healing properties and the germs, or bacteria, are not killed or stopped as expected — is a growing problem. The FIU medical school called antibiotic resistance “one of the biggest public health threats of our time.”
Antibiotic resistance crisis
According to the Centers for Disease Control and Prevention, at least two million people get infected with bacteria that prove resistant to antibiotics and at least 23,000 people die every year as a direct result of these infections.
In February 2018, the World Health Organization warned that “new resistance mechanisms are emerging and spreading globally, threatening our ability to treat common infectious diseases.”
WHO lists infections like pneumonia, tuberculosis, blood poisoning, gonorrhea, and food-borne diseases as those that “are becoming harder, and sometimes impossible, to treat as antibiotics become less effective.”
Rosen said the arsinothricin antibiotic is “a natural product made by soil bacteria and is effective against many types of bacteria, which is what broad-spectrum means. Arsinothricin is the first and only known natural arsenic-containing antibiotic, and we have great hopes for it.”
Although AST contains arsenic, the researchers tested AST toxicity on human blood cells and found that it didn’t kill human cells in the tissue culture.
According to FIU, the new antibiotic was found to be “very effective” against E. coli, which can cause severe intestinal infections, and carbapenem-resistant Enterobacter cloacae, which has been linked to increasing infections in neonatal and intensive care units.
The U.S. and Japan team of scientists also found that AST worked against Mycobacterium bovis, which causes tuberculosis in cattle. “This suggests the potential for treating human tuberculosis,” FIU said in its media release.
The next step — and it’s lengthy — is further testing to determine the antibiotic’s effectiveness and toxicity in animals and humans, patenting the discovery and working with the pharmaceutical industry to turn this into a drug that can be prescribed for the public. This, FIU says, is a costly process that could take 10 years.
“We are running out of tools to fight these diseases. We need a new potent antibiotic to solve this problem,” said Masafumi Yoshinaga, the other co-senior author who is with the Department of Cellular Biology and Pharmacology at FIU. “We showed that this new novel arsenic compound can be a potent antibiotic.”
Researchers from Japan’s Institute for Agro-Environmental Sciences, NARO, were also part of the study’s team with FIU.
As for grade school memories of “Arsenic and Old Lace,” or fans of Frank Capra’s 1944 film adaptation, it’s time to rethink.
“People get scared when they hear the word arsenic because it can be a toxin and carcinogen, but the use of arsenicals as antimicrobials and anti-cancer agents is well established,” Rosen said in the news release. He cited examples including scientist Paul Ehrlich, who won the 1908 Nobel Prize in medicine when he found an arsenic-based cure for syphilis. Arsenicals, FIU noted, “are still used to treat tropical diseases, preventing infectious diseases in poultry, and as a chemotherapeutic treatment for leukemia.”
Rosen added that while the majority of potential drugs fail in the clinical trial stage, the work is still worth the effort. “If you don’t bring new drugs into the pipeline, you won’t find the ones that work.”