From common cold to cancer, the role of vitamin C in combating diseases has long been hailed. Recent research has shown that it can also alleviate arsenic- induced toxic effects. People living in high-risk arsenic contaminated areas can now use the cheap and easily available vitamin C (also known as ascorbic acid) as a dietary supplement.

Arsenic is toxic to the liver, kidney, spleen and heart, leading to a significant increase in the level of reactive oxygen species (ROS) in the bloodstream. ROS are free radicals that include oxygen ions and peroxides. When their levels are high they can damage cell structures, ultimately leading to cancers.

Studies have shown vitamin C to be a well-known antioxidant that can protect the body from damage by ROS. A recent study found vitamin C to inhibit DNA damage in mice caused by arsenic toxicity. This led researchers from the University of Kalyani, West Bengal and Boiron Lab, Sainte-Foy-Les-Lyon, France to embark on the present study.

The researchers divided mice into four groups; the first group was normal and untreated, the second group was dosed only with vitamin C, the third group was injected with arsenic trioxide and the fourth received both arsenic trioxide and vitamin C. At different points of the study period, the animals were killed and their blood samples were analyzed.

The researchers found that arsenic exposure increased the levels of some liver enzymes showing liver toxicity. Normally these enzymes are in low levels in blood but when the liver is damaged they are released in larger amounts into the bloodstream. Arsenic exposure also caused the blood haemoglobin level to drop which in turn led the blood glucose level to rise. In addition, it reduced the activity of antioxidant enzymes and inflicted damage on DNA.

Where vitamin C was given with arsenic, the study found a marked suppression of chromosomal damage and an increase in antioxidant enzymes; levels of blood haemoglobin and blood glucose were restored to normalcy. Treatment with the vitamin also decreased the levels of liver enzymes, indicating proper liver functioning.

"We have not yet ascertained the specific mechanism of action," said lead researcher Anisur Rahman Khuda-Bukhsh from the University of Kalyani. "But our study has shown the positive effects of vitamin C against arsenic intoxication in mice which are mammalian models close to human beings in function and genome," he added.

Source: Down To Earth,
Date: January 2009