Vitamin C may reduce cancer-linked digestive chemical reactions

In continuation of my update on Vitamin C

A new study from the University of Waterloo uses mathematical modeling to examine how Vitamin C affects chemical reactions in the digestive system that are linked to cancer development. 

Over the last several decades, North American diets have seen a steady increase in exposure to nitrates and nitrites: compounds found in cured meats as well as fruits and vegetables grown using polluted soil and water. While nitrates and nitrites play important roles in neurological and heart health, in the stomach, they can undergo a chemical reaction known as "nitrosation" and form chemicals that many scientists suspect increase cancer risk. 

Since at least the 90s, researchers have been studying the link between cancer and these compounds, with conflicting results. Our work suggests that the presence of dietary Vitamin C may help explain these inconsistencies." 

Dr. Gordon McNicol, post-doctoral researcher in applied mathematics and first author of the study

The team built a mathematical model of the salivary glands, stomach, small intestine and plasma, and simulated how nitrites and nitrates move through the body and change over time. Their model demonstrated that when Vitamin C is also present in food, such as leafy greens like spinach, which contain both Vitamin C and nitrate, it could decrease cancer risk. 

The study also suggested that taking Vitamin C supplements after each meal could have a moderate positive effect in reducing the formation of nitrosation products associated with cancer risk from dietary nitrites and nitrates, such as those found in foods like bacon and salami. 

The researchers hope these findings will support future nutrition research. 

"This work provides a mechanistic roadmap for future clinical and laboratory studies by identifying the key interacting drivers of these potentially harmful chemical reactions, including nitrite exposure, antioxidant intake, meal timing, gastric conditions and oral microbiome activity," said Dr. Anita Layton, professor of applied mathematics and Canada 150 researcher chair. "This model can help researchers design more targeted experiments and interventions, focusing on when and in whom nitrosation is most likely to occur." 

The research, "Vitamin C as a nitrosation inhibitor: A modelling study across dietary patterns and water quality," appears in the Journal of Theoretical Biology.

https://www.sciencedirect.com/science/article/pii/S002251932600069X?via%3Dihub

Vitamin C may reduce cancer-linked digestive chemical reactions

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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