Study shows vitamin C kills drug-resistant strands of TB
The study, led by William Jacobs, Jr., professor of microbiology & immunology and genetics at Einstein, and funded by the National Institute of Allergy and Infectious Diseases, was published in the online journal Nature Communications on Tuesday. Jacobs was recently elected a member of the National Academy of Sciences.
During the study, Jacobs and his team were observing isoniazid-resistant TB and noted it was low in the mycothiol molecule. They thought this strand may contain higher levels of the amino acid cysteine.
"So, we predicted that if we added isoniazid and cysteine to isoniazid-sensitive M. tuberculosis in culture, the bacteria would develop resistance," Jacobs said. "Instead, we ended up killing off the culture -- something totally unexpected."
The team hypothesized cysteine was acting as a reducing agent, thus killing the TB by the production of free radicals, damaging the DNA. The team then repeated the experiment with another reducing agent: vitamin C.
"The combination of isoniazid and vitamin C sterilized the M. tuberculosis culture," Jacobs said. "We were then amazed to discover that vitamin C by itself not only sterilized the drug-susceptible TB, but also sterilized multi-drug resistant TB and extensively drug-resistant TB strains."
More research will be required to find both how vitamin C induces its reaction, then how and if it will work in the human body.
"We don't know whether vitamin C will work in humans, but we now have a rational basis for doing a clinical trial," Jacobs said."It also helps that we know vitamin C is inexpensive, widely available and very safe to use. At the very least, this work shows us a new mechanism that we can exploit to attack TB."