An overabundance of natural antioxidants can lead to heart failure in mice carrying a mutation linked to a human condition known as desmin-related myopathy, report researchers led by scientists at the University of Utah, in Salt Lake City (Rajasekaran NS et al. Cell. 2007;130:427-439). In this disorder, an accumulation of certain proteins leads to myopathy, including cardiomyopathy.
Mice with the mutation develop the same symptoms seen in human patients, including heart enlargement, progressive heart failure, and early death. Although the investigators anticipated seeing high levels of oxidative stress in the animals, they found that the animals' hearts were under reductive stress due to an abundance of a natural antioxidant known as glutathione.
Hampton T. Antioxidant Overload. JAMA. 2007;298(10):1152. doi:10.1001/jama.298.10.1152-c