Selenium status and plasma glutathione peroxidase in patients with IgA nephropathy.

Summary The abnormnal proliferation of mesangial cells with IgA deposition in the glomeruli characterizes primitive mesangial glomerulonephritis (IgA nephropathy, IgAN); this disease reduces the normal renal parenchyma while renal function becomes progressively impaired. The possible role of selenium has never been considered in evaluating factors involved in the pathogenesis of IgAN. In this work we compared the Se status of 14 IgAN patients (8 with normal renal function, IgAN NRF; 6 with impaired renal function, IgAN IRF) to that of 14 normal individuals (CG NRF) before and after an oral supplementation with selenite (0.13 mol Se/kg b. w./day for 60 days). The following indices of Se status were measured: Se in plasma and urine samples by PIXE; glutathione peroxidase activity in the cytosol of platelets (PLTs-GSH-Px) and of erythrocytes (RBCs-GSH-Px). Both concentrations and activities of plasma glutathione peroxidase (pl-GPx), a selenoenzyme mainly synthesized in and secreted by the kidney, were measured in plasma samples and results compared among groups. IgAN patients showed lower pl-Se and lower activities of selenoenzymes than normal controls before Se supplementation (p