Iron inhibits respiratory burst of peritoneal phagocytes in vitro

Abstract

Objective. This study examines the effects of iron ions Fe(3+) on the respiratory burst of phagocytes isolated from peritoneal effluents of continuous ambulatory peritoneal dialysis (CAPD) patients, as an in vitro model of iron overload in end-stage renal disease (ESRD). Material and Methods. Respiratory burst of peritoneal phagocytes was measured by chemiluminescence method. Results. At the highest used concentration of iron ions Fe(3+) (100 μM), free radicals production by peritoneal phagocytes was reduced by 90% compared to control. Conclusions. Iron overload may increase the risk of infectious complications in ESRD patients.

Figure 1

Respiratory burst of nonprimed (a) and LPS-primed (100 ng/mL, 20 min) (b) peritoneal phagocytes activated by latex beads suspension (10 μL). Representative time-response curves of CL intensities recorded for 60 min at 37°C in the presence (●) and absence (○) of latex are shown.

Figure 2

Effects of urea ((a) and (b)), creatinine ((c) and (d)), and iron ions Fe³⁺ ((e) and (f)) on respiratory burst of peritoneal phagocytes. Dose-response curves showing the intensities of respiratory burst calculated from AUC values for nonprimed ((a), (c), and (e)) and LPS-primed (100 ng/mL, 20 min; (b), (d), and (f)) cells. Cells were exposed to tested agents for 30 min prior to CL measurements. Results are given as mean ± SEM relative to controls on the basis of five independent experiments.