Glutathione peroxidase protects mice from viral-induced myocarditis

Glutathione peroxidase 1 (GPX-1) is a selenium-dependent enzyme with antioxidant properties, Previous investigations determined that mice deficient in selenium developed myocarditis when infected with a benign strain of coxsackievirus B3 (CVB3/0), To determine whether this effect was mediated by GPX-1, mice with a disrupted Gpx1 gene (Glbx1(-/-)) were infected with CVB3/0, Gpx1(-/-) mice developed myocarditis after CVB3/0 infection, whereas infected wild-type mice (Gpx1(+/+)) were resistant. Sequencing of viruses recovered from Gpx1(-/-)-infected mice demonstrated seven nucleotide changes in the viral genome, of which three occurred at the G residue, the most easily oxidized base, No changes were found in virus isolated from Gpx1(+/+) mice. These results demonstrate that GPX-1 provides protection against viral-induced damage in vivo due to mutations in the viral genome of a benign virus.