CAT and diabetes mellitus: In one study using a rodent model of diabetes, calcitriol supplementation (5,000 IU/kg b.wt./d) for 4 wk prior to diabetes induction increased the antioxidant activity of superoxide dismutase (liver ∼2.9 fold and kidney ∼4.2 fold), glutathione peroxidase (liver and kidney ∼2.2 fold) and catalase (liver ∼2 fold and kidney ∼3.5 fold) compared to diabetic rat controls [35].