(Ivanhoe Newswire) – An anti-cancer drug with potentially dangerous side effects might be made safer and less toxic by the regular inhalation of a gas most people associate with toxic effects itself.

Duke University Medical Center researchers find inhaling carbon monoxide (CO) might be able to ward off serious heart problems in people taking doxorubicin (DOX).

The researchers explain DOX, which is used to treat leukemia and breast cancer, can have adverse effects on the heart because it causes cardiac muscles to deteriorate and leads to the formation of scar tissue, also called fibrosis. These effects result from the drug’s inhibition of a process called mitochondrial biogenesis, which is necessary for proper heart function.
 

In a study conducted in mice, they found inhaling carbon monoxide could restore mitochondrial biogenesis in animals treated with DOX. Mitochondrial biogenesis was also restored by over-expression of a protein known as HO-1.

The effects can be explained by the fact that mitochondrial biogenesis depends on both carbon monoxide and HO-1 to promote the production of energy and defend cells from injury.

The researchers hope these discoveries may one day lead to new ways to avoid the potentially serious side effects of this anti-cancer medication. “CO/HO and/or other activators of mitochondrial biogenesis may provide a rational basis for novel cardioprotective strategies to avoid cardiomyopathy and cardiac fibrosis in at-risk patients,” they write.

SOURCE: The Journal of Clinical Investigation, published online Nov. 21, 2007