Vitamin C found to be highly effective against mycobacterium tuberculosis
A new research published online in the May 21 issue of the journal Nature Communications has found that vitamin C is highly effective against drug-sensitive, multidrug-resistant (MDR), and extensively-drug resistant (XDR) strains of Mycobacterium tuberculosis. The research was carried out by Catherine Vilcheze, PhD, from the Department of Microbiology and Immunology, Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx, New York, along with her colleagues.
The researchers observed that the bactericidal activity of vitamin C is dependent on high ferrous ion levels and reactive oxygen species production. When vitamin C is added to an aerobic culture of drug-sensitive, MDR, and XDR bacteria, the mycobacterium cells accumulate ferrous ions. Vitamin C is known to convert ferric ions into ferrous ions. The latter react with oxygen to form hydroxyl radicals. The hydroxyl radicals thus produced, damage the guanine residues present in the DNA of the mycobacterium. This reaction is known as the Fenton reaction and it results in the death of the mycobacterium. The researchers found that 2mM of vitamin C is the bactericidal level for the mycobacteriim.
It was noticed that compared to other Gram positive and Gram negative bacteria, mycobacterium tuberculosis is far more sensitive to the pro-oxidant effects of vitamin C. On the basis of results obtained from the study, the researchers have opined that adding vitamin C to the conventional anti-tuberculosis treatment may considerably shorten the treatment duration. Similarly, newer drugs can be developed which act against mycobacterium tuberculosis by employing the Fenton’s reaction.
Studies done in the past have also supported the efficacy of vitamin C against mycobacterium. In a research dating back to the 1930s, it was seen that when guinea pigs were administered vitamin C rich tomato juice, only 6% of them developed tuberculosis. On the other hand, 70% of the guinea pigs who were not given the tomato juice went on to develop tuberculosis.
Editor: Dr. Bimal Rajalingam MBBS DNB (Resp Med)
Saturday, September 8, 2012