Superoxide production in cardiac tissue sections, as revealed by dihydroethidium staining (Figure S3f, g), as well as NADPH oxidase (Nox) activity in LV homogenates (Figure S3h) and the expression of genes for the p22phox and gp91phox (Nox2) membrane components of Nox in LV tissue (Figure S3i,j) were all increased in MetS rats compared with CONT rats. Here, CYBB is linked to metabolic syndrome.