Effects of iron supplementation on DNA damage of lymphocytes in rats

Abstract

AbstractIron‐induced oxidative stress has been shown to cause a variety of cell damage. In the current study we investigated the effect of different doses of iron supplementation on DNA damage of lymphocytes in rats. Forty male Wistar rats were randomly divided into four diet groups:1) control (4.5 mg iron/kg·bw), iron deficiency (1.5 mg iron/kg·bw), 10x supplementation (45 mg iron/kg·bw) and 20x supplementation(90 mg iron/kg·bw). Iron was administered by intraperitoneal injection of 0.72ml iron dextran every other day for 6 weeks. After 6 weeks, serum iron levels were determined by spectrophotometyand lymphocytes DNA damage was assessed using comet assay. We found that the serum iron levels in iron deficiency group (53.54 μmol/L) were significantly lower compared tothe control group (77.62μmol/L)(P<0.001), while the serum iron levels in both 10x group (104.77μmol/L) and 20 x group (205.30μmol/L) were significantly higher compared to the control group (P<0.001). We also found that the DNA damage in 10x group (82.80AU) and 20x group (169.50AU) was significantly higher compared to the control group (21.13AU, P<0.001). In addition, the DNA damage induced by 10μmol/L H2O2 showed a significantly higher oxidative DNA damage in 10xgroup (293.80AU) and 20x group (308.88AU) compared to the control group(259.00AU, P<0.001). In conclusion, iron overload as supplemented with 10x and 20x of the adequate (control) level may induce oxidative damage tolymphocyte DNA .Supported by NSFC‐81373000.