Mycobacterium tuberculosis is extraordinarily sensitive to killing by a vitamin C-induced Fenton reaction : Nature Communications : Nature Publishing Group

In a striking, unexpected discovery, researchers at Albert Einstein College of Medicine of Yeshiva University have determined that vitamin C kills drug-resistant tuberculosis (TB) bacteria in laboratory culture. The finding suggests that vitamin C added to existing TB drugs could shorten TB therapy, and it highlights a new area for drug design.

Dr. Jacobs and his colleagues observed that isoniazid-resistant TB bacteria were deficient in a molecule called mycothiol. "We hypothesized that TB bacteria that can't make mycothiol might contain more cysteine, an amino acid," said Dr. Jacobs. 

"So, we predicted that if we added isoniazid and cysteine to isoniazid-sensitive M. tuberculosis in culture, the bacteria would develop resistance. Instead, we ended up killing off the culture  something totally unexpected."

The Einstein team suspected that cysteine was helping to kill TB bacteria by acting as a "reducing agent" that triggers the production of reactive oxygen species (sometimes called free radicals), which can damage DNA.

"To test this hypothesis, we repeated the experiment using isoniazid and a different reducing agent vitamin C," said Dr. Jacobs. "The combination of isoniazid and vitamin C sterilized the M. tuberculosis culture. We were then amazed to discover that vitamin C by itself not only sterilized the drug-susceptible TB, but also sterilized MDR-TB and XDR-TB strains."

To justify testing vitamin C in a clinical trial, Dr. Jacobs needed to find the molecular mechanism by which vitamin C exerted its lethal effect. More research produced the answer: Vitamin C induced what is known as a Fenton reaction, causing iron to react with other molecules to create reactive oxygen species that kill the TB bacteria.

"We don't know whether vitamin C will work in humans, but we now have a rational basis for doing a clinical trial," said Dr. Jacobs. "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.".....

Ref : http://www.einstein.yu.edu/news/releases/907/study-finds-vitamin-c-can-kill-drug-resistant-tb/


Mycobacterium tuberculosis is extraordinarily sensitive to killing by a vitamin C-induced Fenton reaction : Nature Communications : Nature Publishing Group

When Having the Blues is a Good Thing: Blueberries & Cancer Prevention

In continuation of my up date on the usefulness of blue berries.

Now researchers from the Department of Nutrition Sciences at the University of Alabama at Birmingham, lead by Laura Newton have come up with another interesting finding about blue berries, i.e., as little as a cup a day can help prevent cell damage linked to cancer.

As per the claim by the researchers, free radicals, atoms that contain an odd number of electrons and are highly reactive, can cause cellular damage, one of the factors in the development of cancer; many believe a diet filled with fruits and vegetables may help reduce the risk. 

Lead researcher says

"Studies suggest that antioxidants may help prevent the free-radical damage associated with cancer"

Researchers add that, Blueberries also are rich in vitamin C, which helps the immune system and can help the body to absorb iron. "Vitamin C also helps to keep blood vessels firm, offering protection from bruising. Blueberry juice and other products may be nutritious but often contain less fiber than the whole fruit, and added sugar or corn syrup may decrease their nutritional value. Consuming fresh, raw blueberries provides the most benefits; the average serving size of raw blueberries is one cup, which contains about 80 calories...

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