Increased glomerular and extracellular malondialdehyde levels in patients and rats with focal segmental glomerulosclerosis

Abstract

Evidence suggests an increase in oxidative stress in patients with chronic kidney disease, as glomerulosclerosis is the prerequisite for chronic kidney disease; whether the oxidative stress already exists early on is not known. In this study we measured the plasma and urinary levels of malondialdehyde (MDA), the end product of lipid peroxidation, and assessed the immunoreactivity of MDA and superoxide dismutase (SOD) in glomeruli of patients and rats with primary focal segmental glomerulosclerosis (FSGS), and compared our findings with those of minimal change disease (MCD) and normal controls (NC). Our results showed that plasma MDA level was significantly increased in patients with FSGS compared with both patients with MCD and normal controls. The urinary MDA level was also significantly increased and was significantly correlated with plasma MDA level in patients with FSGS. The immunostaining for glomerular MDA and SOD was significantly higher in the patients with FSGS than in either the patients with MCD or NC, and was also significantly higher in rats with puromycin aminonucleoside (PAN)-induced FSGS than in rats with MCD. Glomerular MDA level was significantly correlated with the degree of glomerulosclerosis in the patients with FSGS. Our data suggest that oxidative stress occurs early on before the onset of renal failure, and may play an important role in the pathogenesis of glomerulosclerosis.