CAT and systemic lupus erythematosus: According to a previous study, lipid peroxidation level significantly increased in SLE patients, whereas anti-oxidant enzyme activities like those of super oxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and anti-oxidant molecule glutathione (GSH) more significantly reduced in SLE patients than in the control cases [7–9].