Iron-induced oxidative stress in haemodialysis patients: a pilot study on the impact of diabetes.
BACKGROUND
Administration of intravenous iron preparations in haemodialysis patients may lead to the appearance of non-transferrin bound iron which can catalyse oxidative damage. We investigated this hypothesis by monitoring the oxidative stress of haemodialysis patients and the impact of iron and diabetes mellitus herein.


METHODS
Baseline values of serum iron and related proteins, transferrin glycation, non-transferrin bound iron, antioxidant capacity and lipid peroxidation (malondialdehyde) of 11 haemodialysis patients (six non-diabetic and five type 2 diabetes) were compared to those of non-haemodialysis control subjects (non-diabetic and type 2 diabetes). Changes in these parameters were monitored during haemodialysis before and after iron administration.


RESULTS
Baseline values of malondialdehyde correlated with ferritin concentration (r = 0.664, P = 0.036) and were elevated to the same extent in non-diabetic and diabetic haemodialysis patients (median of 1.09 compared to 0.60 mumol/l in control persons, P < 0.02). After iron infusion, transferrin saturation increased more markedly in non-diabetic subjects from 28% to 185% vs. from 33% to 101% in diabetic patients (P = 0.008). This increase was accompanied by the appearance of non-transferrin bound iron (5.91 +/- 1.33 micromol/l), a loss in plasma iron-binding antioxidant capacity and a further increase in malondialdehyde which was more pronounced in diabetic patients (from 0.93 +/- 0.30 micromol/l to 2.21 +/- 0.69 micromol/l vs. from 1.21 +/- 0.42 micromol/l to 1.86 +/- 0.56 micromol/l in the non-diabetic subjects, P = 0.046).


CONCLUSIONS
In haemodialysis patients, higher lipid peroxidation is determined by higher body iron stores. The increase induced by iron infusion is accompanied by a loss in iron-binding antioxidant capacity and is more pronounced in diabetes mellitus.
Van Campenhout
Ann
A
Vascular Biology Unit, James Cook University, Townsville, Australia.
Van Campenhout
Christel
C
Lagrou
Albert
A
Manuel-y-Keenoy
Begoña
B
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000975:Antioxidants / Q000378:metabolism; D001774:Blood Chemical Analysis; D003920:Diabetes Mellitus / Q000378:metabolism*; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D007501:Iron / Q000097:blood*; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress; D010865:Pilot Projects; D006435:Renal Dialysis / Q000009:adverse effects
D000975:Antioxidants; D008315:Malondialdehyde; D005293:Ferritins; D007501:Iron