High Doses of Antioxidants Can Mutate Your Stem Cells

Hold off on the megadoses of antioxidant vitamins like C and E. A study by researchers at Cedars-Sinai Heart Institute shows that you can overdose on these health aids, and the result could be mutated stem cells that cause cancer.

There's no cause for alarm if you're staying within suggested doses of your vitamins or nutritional supplements. This study looked only at what happens when people take much more than the standard amounts of antioxidants.

Researcher Eduardo Marbán and his colleagues' stumbled on the antioxidant problem while they were researching tissue engineering for human hearts. Using stem cells, Marbán and his team are working on a way to grow heart tissue to repair damage caused by heart attacks. Patients who suffer from damaged hearts undergo two quick procedures: First, the researchers collect a few cells from the patients' hearts that will be used to grow the replacement tissue; Second, the new tissue is injected, with no dangers of rejection since it's grown from the patients' own body.

According to a release about their project:

Marbán and his team accidentally discovered the danger of excessive antioxidant doses while seeking a way to reduce the genetic abnormalities that occurred naturally when the scientists sought to multiply human cardiac stem cells . . . In laboratories, stem cells are often grown in a Petri dish culture than is composed of 20 percent oxygen, whereas cells growing inside human tissue are exposed to just 3 to 5 percent oxygen. But Marbán's team of researchers became frustrated because the higher concentration of oxygen in lab-grown stem cells resulted in 9 percent of the cells being rejected because of genetic abnormalities.

"We sought to counter that oxidation problem by adding high doses of antioxidants directly to the cells," Marbán said. "That's when we made the serendipitous discovery that there is a danger zone for the cells exposed to antioxidants to develop genetic abnormalities that predispose to cancer."

This is good to know, but when will we find out the really cool stuff, like whether this project to repair damaged hearts will work? Clinical trial results on the heart procedure are expected in early 2011, so you might have a heart repaired with stem cells as early as 2012.

Full scientific paper via Stem Cells